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1

Song, Qi Jun. "Elemental speciation in the composting process by ICPMS." Thesis, University of Hull, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.397887.

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2

Fung, Shun On. "Reduction of odor generation through composting process control." HKBU Institutional Repository, 2007. http://repository.hkbu.edu.hk/etd_ra/827.

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3

Chan, Man Ting. "Optimizing food waste composting process in fed-batch composter." HKBU Institutional Repository, 2015. https://repository.hkbu.edu.hk/etd_oa/217.

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Composting is considered as an effective and sustainable food waste treatment technology from the perspectives of volume reduction, stabilization and releasing the pressure on landfills. Community composter is a decentralized composting facility in fed-batch operational mode which is usually being installed in the backyard of institutes, hospitals, housing estate etc. to handle the food wastes generated daily. Albeit numerous operational issues including high initial acidity and oil content, poor decomposition and odor generation are commonly encountered in these facilities, which make it difficult to be accepted by the public. Therefore, the aim of the present study is to develop a composting mix formulation that can provide a solution to all these issues in a fed-batch food waste composting process. The first phase of this study aims at finding out an optimized formulation in a batch-scale food waste composting process through the use of alkaline amendments and microbial inoculum. For the first two experiments, artificial food wastes were prepared by mixing 1.3kg bread, 1kg boiled rice, 1kg cabbage, 0.5kg fully boiled pork and mixed with sawdust to obtain a C/N of 30 and adjusted moisture of the mixtures to 55%. The effect of different concentrations of zeolite compared to lime was studied in the first experiment. Zeolite was amended with food wastes and sawdust mixtures at 2% (ZI-2), 5% (ZI-5), 10% (ZI-10) to compare with lime in 2.25% (L-2.25) w/w (dry weight basis) and composted for 56 days. Results demonstrated that 10% of zeolite was optimal amendment rate compared to lower dosage of zeolite (2% & 5%) with stronger pH buffering capacity and greater decomposition efficiency. Addition of 2.25% of lime buffered the pH efficiently but increased the ammonia loss significantly which eventually reduced total nitrogen (TN) content of final product and posed odor emission problem. Amendment of 10% zeolite provided a higher adsorption affinity on ammonia resulting in 2.05% of TN value of final product which was higher than 1.72% of lime treatment. Furthermore, significantly higher seed germination 150% was achieved of ZI-10 compost compared to 135% of L-2.25 due to low ammonium content of product. The first experiment showed that application of less than 10% zeolite was not sufficient to buffer the acidity; as a result, organic matter decomposition was inhibited. However, the cost and reduction in treatment percentage of food waste in 10% application rate of zeolite is an issue of concern. To tackle this dilemma, food waste was amended with struvite salts at 1:2 molar ratio of MgO and K2HPO4 (Mg:P) with or without zeolite amended at either 5% or 10% amendment (Mg:P, Z5 + Mg:P & Z10 + Mg:P) and a control treatment with food waste only was also included. Results showed that treatment of Z10 + Mg:P was synergistically achieved of pH and EC buffering, and N conservation but not for the case of 5 % zeolite. Treatment of Z10 + Mg:P further reduced the N loss to 18% compared to 25% and 27% of Mg:P and Z5 + Mg:P respectively. However, there was insignificant difference in the final nitrogen content and decomposition rate among all treatments with struvite salts amendment. Comparing to the treatment of Z-10 of the first experiment to Z10 + Mg:P of the second experiment, Z-10 showed superior performance since better decomposition efficiency, shorter time to require to pass the GI (28 Days) and lower cost because of salts exclusion. To develop a multipurpose formulation for the fed-batch operational food waste composter, high lipids problem in food waste cannot be neglected because it is a critical factor to hinder the decomposition efficiency. Inoculation of oil degradative microorganisms was reported as an effective approach to facilitate the lipids. Therefore, the third experiment was to investigate the overall composting performance supplemented with 10% zeolite and microbial consortium. 10% zeolite with bacterial consortium significantly reduced the lipid contents from 7% to 1% compared to control treatments. Furthermore, treatments amended with 10% zeolite was proved to reduce ammonia emission and total volatile fatty acids level in the composting mass, therefore the total odor emission level can be reduced. Zeolite at 10% was found to be a suitable optimum additive for both synthetic and real-food wastes. Therefore, treatment of 10% zeolite with bacterial consortium is selected as an optimized formulation for further study of its application in a fed-batch composter. Following the food waste zeolite composting formulation obtained in Phase I, the aim of Phase II was to develop an ideal composting mix formulation for on-site commercial composters. Although the results have been demonstrated 10% zeolite with bacterial consortium facilitated the composting efficiency in batch composter, those amendments may be over-estimated if applied in a fed batch composter by using real food wastes. With this constraint, the applicability of these additives in commercial fed-batch composter needs to be assessed using locally generated food wastes. Treatments included food waste and sawdust mixtures at 4:1 mixing ratio (wet weight basis) were mixed with 2.25% of lime (L2.25), 10% of zeolite (Z10) and 10% zeolite with bacterial inoculum (Z10+O) and a control of food waste with sawdust mixture only was also included. 35 kg compost mixture was fed into each composter respectively daily for a period of 42 days. Only Z10+O was the most suitable composting mix for fed-batch food waste composting process with continuous sustained high temperature (55-60oC), optimal moisture (55%-60%), alkaline pH and low EC during the experimental period. Bacterial inoculum significantly improved the lipids decomposition from 22.16% (C) to 3.10% (Z10+O) after the composting period. In contrast, lime and zeolite alone treatments could not maintain the optimal pH that led to reduce degradation and longer stabilization period. Only compost taken from Z10+O treatment could be classified as mature compost. The aim of the third study phase was to examine an optimal application rate of food waste compost produced from decentralized food waste composter for plant. A plant growth experiment was conducted in this phase to evaluate the change in soil properties and plant growth of Brassica chinensis and Lycopersicon esculentum. The experiment was conducted in a loamy soil amended with 0%, 2.5%, 5% and 10% food waste compost amendment rate compared to the control soil with chemical fertilizer amendment only. Results indicated that 5% was the optimal application rate of food waste compost for both crops among all treatments which can be evidenced by the highest biomass production and nutrients value of the plant tissues. Plant available nutrients such as NH4+, NO3-, PO43- were proportionally increased with increase in compost application rate. However, 2.5% of the food waste compost did not provide sufficient nutrients for plant growth and 10% showed negative effects due to increased salts content. Plants amended with chemical fertilizer had relatively low biomass production compared to compost amended treatments due to soil compaction and fast leaching of nutrients. It can be concluded that application of 10% zeolite with microbial consortium is an ideal composting mix formulation for on-site commercial composters and 5% is an optimal application rate of food waste compost of Brassica chinensis and Lycopersicon esculentum
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4

Francois, A. Joyce. "Composting phosphorus fertilizer with organic wastes to stablize the fertilizer against fixation by phosphate-fixing soils." Thesis, University of Oxford, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.236297.

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5

Abu, Qdais Hani A. "Management of municipal solid waste composting process in hot climates." Thesis, University of Newcastle Upon Tyne, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.242361.

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6

Mangum, Lauren Heard. "Treatment of Timtek process water by co-composting and aqueous phytoremediation." Master's thesis, Mississippi State : Mississippi State University, 2009. http://library.msstate.edu/etd/show.asp?etd=etd-04022009-101708.

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7

Mason, Ian George. "A study of power, kinetics, and modelling in the composting process." Thesis, University of Canterbury. Civil Engineering, 2007. http://hdl.handle.net/10092/1214.

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This thesis explores the roles of physical and mathematical modelling in the prediction of temperature profiles in the composting process. A literature-based evaluation of the performance of laboratory- and pilot scale composting reactors, showed that physical models used in composting research frequently do not properly simulate the full-scale composting environment, and may therefore produce results which are not applicable at full scale. In particular, self-heating, laboratory-scale, reactors typically involve significant convective/conductive/radiative losses, even with insulation present. This problem can be overcome by using controlled temperature difference or controlled heat flux laboratory reactors, which allow convective/conductive/radiative heat fluxes to be controlled to levels close to those occurring in full-scale systems. A new method of assessing the simulation performance of composting systems is presented. This utilises the areas bounded by the temperature-time profile and reference temperatures of 40 and 55 ℃ (A₄₀ and A₅₅), the times for which these temperatures are exceeded (t₄₀ and t₅₅), and times to peak temperature. An evaluation of published temperature profiles showed a marked difference in these parameters when comparing many laboratory- and full-scale reactors. The impact of aeration is illustrated, and laboratory- and pilot-scale reactors able to provide good temperature profile simulation, both qualitatively and quantitatively, are identified. Mathematical models of the composting process are reviewed and their ability to predict temperature profiles assessed. The most successful models in predicting temperature profiles have incorporated either empirical kinetic expressions, or utilised a first-order model, with empirical corrections for temperature and moisture. However, no temperature models have been able to predict maximum, average and peak temperatures to within 5, 2 and 2 ℃ respectively, or to predict the times to reach peak temperatures to within 8 h, although many models were able to successfully predict temperature profile shape characteristics. An evaluation of published constant-temperature and varying-temperature substrate degradation profiles revealed very limited evidence to support the application of single exponential, double exponential or non-logarithmic Gompertz functions in modelling substrate degradation kinetics, and this was identified as a potential weakness in the temperature prediction model. A new procedure for correcting substrate degradation profiles generated at varying temperature to a constant temperature of 40 ℃ was developed and applied in this analysis, and on experimental data generated in the present work. A new approach to the estimation of substrate degradation profiles in the composting process, based on a re-arrangement of the heat balance around a reactor, was developed, and implemented with both a simulated data set, and data from composting experiments conducted in a laboratory-scale constant temperature difference (CTD) reactor. A new simulated composting feedstock for use in these experiments was prepared from ostrich feed pellets, office paper, finished compost and woodchips. The new modelling approach successfully predicted the generic shape of experimental substrate degradation profiles obtained from CO2 measurements, but under the conditions and assumptions of the experiment, the profiles were quantitatively different. Both measured CO2-carbon (CO2-C) and predicted biodegradable volatile solids carbon (BVS-C) profiles were moderately to well fitted by single exponential functions with similar rate coefficients. When corrected to a constant temperature of 40 ℃, these profiles gave either multi-phase or double exponential profiles, depending upon the cardinal temperatures used in the temperature correction procedure. If it is assumed that the double exponential model generated is correct, this work provides strong evidence that a substrate degradation curve generated under appropriate laboratory conditions at 40 ℃ would, given the correct cardinal temperatures, generate a correct substrate degradation profile under varying temperature conditions, and that this in turn would enable an accurate and precise prediction of the temperature profile using a heat and mass balance approach. This finding opens the door for the development of a simple laboratory test for composting raw material characterisation, but underlines the need for accurate estimates of the physical cardinal temperatures. Experimental factors appear to be the likely cause of the dysfunction between previously reported substrate degradation patterns and existing substrate degradation models, and suggestions for further research are provided in order to more precisely and accurately quantify these factors.
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8

Christian, Archer H. "Municipal yard waste composting : process parameters, windrow gases, and leachate quality /." Thesis, This resource online, 1995. http://scholar.lib.vt.edu/theses/available/etd-06112009-063549/.

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9

Wang, Xuan. "Nitrogen conservation by struvite formation during composting process with food wastes." HKBU Institutional Repository, 2015. https://repository.hkbu.edu.hk/etd_oa/201.

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Food waste as a dominant fraction of municipal solid waste was in most of cases buried in landfills creating a burden on big cities with large populations such as Hong Kong. Composting provided an environmentally viable technology to divert food waste to resource utilization for the production of valuable organic fertilizer. The main problem associated with food waste composting was the intensive acidification prior the commencement of the composting process, which is commonly adjusted by the addition of alkaline materials such as lime. However, more than 50% of the initial nitrogen will be lost as ammonia, which not just reduces the nutrient value of the compost but also leads to serious odour generation. Therefore the objective of this study was to develop means to reduce the nitrogen loss through struvite formation. The first experiment of this research investigated the feasibility of controlling the nitrogen loss through struvite formation during food waste composting. Struvite forms when magnesium (Mg), phosphorus (P) and nitrogen (N) salts exist in equimolar ratio at a slightly alkaline pH. Thus to fix the ammonia, MgO and K2HPO4 were added to food waste indifferent molar ratios (P1, 0.05M/kg MgO and 0.05M/kg K2HPO4; P2, 0.05M/kg MgO and 0.1M/kg K2HPO4) to induce struvite formation that can fix the compost-borne ammonia during composting. The pH of the composting mass of P1 was below 5 for more than one. However, the pH of P2 was controlled in a narrow range from 6.8 to 8.7. This slightly alkaline pH ensured a good microbial activity and improved the degradation rate as well as the precipitation of struvite. In treatment P2, the formation of struvite effectively reduced the nitrogen loss from 40.8% to 23.3% when compared to treatment with lime amendment. However, electrical conductivity (EC) of the compost increased to 6.4 mS/cm due to the addition of Mg and P salts. High salinity of the compost retarded seed germination which required further investigation to reduce the salinity while maintaining good nitrogen removal. To overcome this issue, lime as the more effective alkaline amendment, was supplemented in different concentrations along with struvite salts (to P1 treatment having less Mg salt that could reduce the salinity) to alleviate the low pH and struvite formation. The pH of the composting masses were effectively increased with increasing lime dosages and 2.25% lime was sufficient to maintain the pH in alkaline condition that significantly improved the degradation of active organic compounds resulting in increased dissolved organic carbon (DOC) and soluble organic nitrogen (SON) contents. With 2.25% lime and struvite salts, ammonia emission was significantly reduced from 44.3 to 27.4% through struvite formation compared with lime alone treatment. Furthermore, the EC were also decreased from 5.21to 3.40 mS/cm when lime amendment rate increased from 0.75% to 3%. However, the ammonia emission increased with an increase in lime dosage. Interfering ions such as calcium and potassium were reported to affect the struvite formation and pH control. Therefore, in the subsequent experiment, the influence of different types of P salts was investigated to reduce the salinity as well as N loss. When K2HPO4, Na2HPO4 and H3PO4 were used as the supplementary P salts, there were no significant differences on nitrogen conservation. In addition, the results indicated that K+ and Na+ were attached on the surface of struvite rather than constituted the crystal structure. Compared with other P salts, the presence of K+ in K2HPO4 also made a contribution to total nutrient content that benefited the final product. When CaO was gradually substituted with MgO as pH amendment, ammonia emission was significantly reduced implying that Ca2+ ions would influence the struvite formation, either by competing for phosphate ions or by interfering with the crystallization. However, this negative effect could be ignored when the Ca2+/Mg2+ ratio was below 1:2. Considering the cost of MgO, supplementation of Ca2+/Mg2+ ratio at 1:2 (0.15M CaO and 0.3M MgO) with 0.05M K2HPO4 was identified as the optimum conditions (Treatment M0.3) that effectively reduced the nitrogen loss to 28% in contrast to 46% with lime addition. The significant reduction of ammonia emission through struvite formation was observed with the optimum condition that the odour unit (OU) of ammonia emission was reduced to 1.8×104 when compared with lime treatment (3.0×104) indicating a significant reduction of OIMAX (maximum odour index). Meanwhile, the well-controlled pH of this technology ensured the effective decomposition of organic matter that significantly reduced the emission of volatile fatty acids (VFAs) also. The population of total bacteria was also improved due to the addition of phosphate salts. The total nutrient content of struvite composts of treatment with optimum condition (M0.3) was 4.14% (1.5% N, 0.44% P and 2.2% K) that was higher than normal lime treated compost 2.92% (1.3% N, 0.34% P and 1.28% K). In pot experiment, soil was amended with composts at 0, 2.5%, 5% or 10% (w/w dry wt. basis). At the same application rate, the biomass yields of Chinese cabbage and cherry tomato plants were improved by struvite compost when compared tonormal compost. Considering the increasing salinity of soil with high application rate, the optimum dosage of 5% struvite compost is recommended. To conclude, a food waste composting technology was developed to achieve good nitrogen conservation and decomposition that alleviated odour issue and produced compost with higher nutrient contents, which increased its application value
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10

Robinson, J. J. "Composting of sewage sludge using aerated static piles under varying process conditions." Thesis, University of Leeds, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.505923.

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11

Hultman, Jenni. "Microbial diversity in the municipal composting process and development of detection methods." Helsinki University of Helsinki, 2008. http://urn.fi/URN:ISBN:978-952-10-5183-8.

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12

Liu, Yeqing. "Comparative analysis of composting as a municipal solid waste treatment process in India." Thesis, Massachusetts Institute of Technology, 2015. http://hdl.handle.net/1721.1/99568.

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Thesis: M. Eng. in Environmental Engineering, Massachusetts Institute of Technology, Department of Civil and Environmental Engineering, 2015.
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 57-60).
A study of composting municipal solid waste (MSW) in India compared a specific facility in Muzaffarnagar, Uttar Pradesh, India to existing standards and practices documented in literature globally and in other facilities in India. The scope of this study included an analysis of issues in various facilities around the world in light of relevant government regulations, perceptions, and social values. From these results, short term low cost improvements were proposed to increase efficiency and sustainability of the facility in Muzaffarnagar. Long term improvements were proposed to address inefficiencies within the Indian industrial municipal solid waste composting system as a whole.
by Yeqing Liu.
M. Eng. in Environmental Engineering
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13

Ekinci, Kamil. "Theoretical and experimental studies on the effects of aeration strategies on the composting process /." The Ohio State University, 2001. http://rave.ohiolink.edu/etdc/view?acc_num=osu1486399160105951.

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14

Sayara, Tahseen A. S. "Bioremediation of polycyclic aromatic hydrocarbons (PAHs)-contaminated soil: process evaluation through composting and anaerobic digestion approach." Doctoral thesis, Universitat Autònoma de Barcelona, 2010. http://hdl.handle.net/10803/32128.

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Among the different available remediation technologies, it is well-known that bioremediation methods which mainly depend on microorganisms to degrade, transform, detoxify or break down the contaminants, they are recognized as cost-effective and environmental-friendly methods. In fact, microorganisms “engine of bioremediation process” carry out their normal duty under aerobic or anaerobic conditions, which without doubt extends and motivates the desires to make use of such abilities to reduce environmental threats caused by various contaminants. However, to achieve satisfactory results during any bioremediation process, providing optimal conditions for microorganisms is considered as an essential/crucial task. Composting as one of the applied bioremediation technologies used to remediate soils contaminated with organic contaminants like PAHs still needs more investigation although a valuable effort has been devoted to elucidate the behaviour of this process in the remediation of PAHs-contaminated soils. However, till recently, anaerobically treatment of PAHs-contaminated soil received less attention as it was believed that PAHs are poorly or even impossible to be degraded under such conditions. Therefore, the present study tried to touch both aerobically bioremediation of PAH-contaminated soil through composting and anaerobically treatment of the same soil under strict methanogenic conditions. For both remediation approaches, the effect of some controlling factors had been also evaluated through experiment design methodology employing central design (CCD) technique. Regarding the composting process, the obtained results demonstrated that this technology is an advantageous and indisputable method to decontaminate PAHs-contaminated soils within short period. Additionally, compost derived from the organic fraction of municipal solid wastes (OFMSW) was found to enhance the contaminants (PAHs) removal rate to high extent. Moreover, a lucid correlation between the contaminants removal rate and the compost stability degree was observed, such that more stable composts better enhanced the remediation process as these composts are believed to have a considerable fraction of humic matter which facilitates the desorption of the contaminants, and get more available as a consequence. At the same time, treatments with stable composts do not produce high temperature during the composting process, and normally they are in the mesophilic ranges which are more favourable for such bioremediation process. Bioaugmentation of the process through introducing white-rot fungi with desired catalytic capacity (Trametes Versicolor) in attempt to accelerate the degradation process demonstrated that no effect or enhancement was achieved through such approach. In the second part of the research, anaerobically treatment of PAHs-contaminated soil has been investigated under strict methanogenic conditions employing two types of inocula; thermophilic and mesophilic. The obtained results demonstrated the effectiveness of such biological treatments in this field. Nevertheless, the process was relatively less effective compared with composting. Furthermore, under these conditions and due to unclear reasons, reversible results were obtained as PAHs concentrations were increased with prolonged incubation, indicating the reversed bioformation of PAHs under such oxygen-deficient conditions. Therefore, future work should be devoted to clarify the reasons behind this behaviour.
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15

Rillo, Moral Francesc. "New autonomous sensor system for the continous monitoring of the composting process from the inside." Doctoral thesis, Universitat Politècnica de Catalunya, 2016. http://hdl.handle.net/10803/396130.

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The composting process is Nature's way of recycling organic wastes with a good quality organic fertilizer as a result. This process, though, needs of a thoroughly monitoring of temperature and humidity for a good resulting material. During this Ph.D thesis we developed a wireless temperature and humidity autonomous system that monitored from the inside of compost. The fact of measuring and transmitting from the inside implies the need of a protection for the circuit and an issue in the measure. Temperature suffers delays when measuring from the inside of a protection and, as such, we developed an algorithm, implementable on microcontrollers, to counteract the effects of first order step responses. The conditioning has been optimized in terms of components and consumption, obtaining a theoretical and experimental comparative between the classic conditioning and the use of direct interfaces. Commercial humidity sensors need to be in direct contact with the environment they are measuring, but that is not possible in compost since they can get damaged. That is why we designed a humidity sensor based on coplanar capacitive electrodes that can measure through a protection layer. Some theoretical models have been obtained for the physical optimization of both the sensor and the influence of the protective layer. Compost has never been characterised as a transmission environment, and as such, communications in compost are innovative. The heterogeneity of the material and its changes in humidity, temperature and density made the transmission complex. We found the proper frequency band to commercially work in compost and the RF transmission model in compost to estimate attenuation vs distance.
El procés de compostatge és la forma que té la natura de reciclar els residus orgànics amb un fertilitzant orgànic de bona qualitat com a resultat. Aquest procés, però, necessita d’una monitorització de la temperatura i la humitat per a obtenir un bon material resultant. Durant aquesta tesi doctoral s'ha desenvolupat un sistema autònom sense fils de mesura de temperatura i humitat des de dins del compost. El fet de que la mesura i la transmissió s’hagin fet des de dins comporta la necessitat d’un material protector per l’electrònica, la qual cosa esdevé un problema en la mesura. La temperatura pateix retards quan es mesura des de dins d’un material protector, i per això, s’ha desenvolupat un algoritme implemetanble en microcontroladors per contrarestar els efectes de respostes esglaó de primer ordre. S'ha optimitzat el condicionament des del punt de vista de components i consum, obtenint una comparativa teòrica i experimental entre els mètodes de condicionament clàssic i l'ús d'interfícies directes. Els sensors de humitat comercials necessiten estar en contacte directe amb l’ambient a mesurar. Això no és possible en el compost ja que es poden malmetre. Per això s’ha dissenyat un sensor d’humitat basat en elèctrodes capacitius plans que poden mesurar a través de capes de protecció. S'han extret models teòrics per l’optimització física tant del sensor com de la influencia de la capa protectora El compost no ha estat mai caracteritzat com un medi de transmissió, i per tant, les comunicacions dins del compost suposen una novetat. La heterogeneïtat del material i els seus canvis en temperatura, humitat i densitat fan de la transmissió un tema complex. S’ha trobat, a més, la banda de freqüència òptima per treballar comercialment i el seu model de transmissió RF estimant l’atenuació en funció de la distància
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Silva, Maria Elisabete Ferreira. "Optimization of the humification process during composting and recovery evaluation of the humic-like substances." Doctoral thesis, ISA, 2013. http://hdl.handle.net/10400.5/6971.

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Doutoramento em Engenharia do Ambiente - Instituto Superior de Agronomia
This work aimed to contribute to the knowledge about the formation of humic-like substances (HS-like) during composting and to assess the recovery of these substances from commercial compost with low quality. Several mixtures with raw materials of known composition (wheat flour, dog food) were composted. First, it was studied the influence of mild solvents, sodium and potassium pyrophosphate, in the yield and characteristics of extracted HS-like, as well as in the coextraction of heavy metals from compost. Secondly, it was assessed the influence of raw materials, presence of bulking agent and initial C/N ratio on the humification during composting. Third, commercial composts were used as HS-like source. In all phases, composts and HS-like were characterized using the conventional physical, chemical, stability and maturity parameters. The fractionation of heavy metals was also determined. Results showed that potassium pyrophosphate can be used advantageously for the HS-like extraction. During composting the HS-like content were influenced by presence of carbon rich raw materials and the initial C/N ratio, being their production independently of the composts quality. The HS-like produced from commercial composts showed low level of co-extracted heavy metals, however, the presence of Cu, Cr and Pb can influence negatively their composition.
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17

Sundberg, Cecilia. "Improving compost process efficiency by controlling aeration, temperature and pH /." Uppsala : Swedish University of Agricultural Sciences, 2005. http://epsilon.slu.se/2005103.pdf.

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18

Barretto, Vitor Corrêa de Mattos [UNESP]. "Resíduos de indústria de celulose e papel na fertilidade do solo e no desenvolvimento de eucalipto." Universidade Estadual Paulista (UNESP), 2008. http://hdl.handle.net/11449/105180.

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Made available in DSpace on 2014-06-11T19:33:38Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-09-29Bitstream added on 2014-06-13T20:45:33Z : No. of bitstreams: 1 barretto_vcm_dr_jabo.pdf: 364350 bytes, checksum: f015dad17989bbca79656ebee759afb5 (MD5)
Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
Foram conduzidos experimentos em casa de vegetação e em condições de campo, com os seguintes objetivos: a) avaliar o efeito de doses de composto de resíduos de indústria de celulose e papel na fertilidade do solo, no desenvolvimento, na produção de matéria seca e na concentração e acúmulo de nutrientes nas folhas de um clone de Eucalyptus grandis x E. urophylla; b) avaliar os efeitos da aplicação em diferentes épocas de dois resíduos da indústria de celulose e papel (lodo ativado e não decomposto e dregs + grits), no desenvolvimento das árvores, produção de madeira e acúmulo de nutrientes nas folhas de um clone de Eucalyptus grandis x E. urophylla. As principais conclusões foram: a) A aplicação de composto de resíduos de indústria de celulose e papel (CRICP) propiciou ganhos em altura aos 60 dias após o plantio em colunas de PVC, em diâmetro do coleto e em produção de biomassa das plantas de eucalipto aos 120 dias. O CRICP resultou em aumento no valor de pH e nos teores de Ca e Mg do solo. Também elevou os teores de P, K e Na no solo. A concentração nas folhas e o acúmulo de P, K, Ca e S aumentaram com a aplicação do composto; b) Os resíduos da fábrica de celulose e papel são eficientes corretivos da acidez do solo. A aplicação de 8 t ha-1 de dregs + grits no plantio proporcionou maior crescimento em diâmetro e produção de madeira de eucalipto do que a aplicação de 15 t ha-1 de lodo ativado não decomposto. Essa dose e elevou os teores de Ca e Mg e a porcentagem de saturação por bases de Latossolo Vermelho distrófico para valores adequados para uma produtividade de madeira de 40 m3 ha-1 ano-1, aos 6,5 anos, quando aplicados no plantio ou três meses após o mesmo.
Experiments in greenhouse and field were carried out with the objectives: a) to evaluate the effect of industrial residues from pulp and paper mill compost rates on soil fertility, on development, on dry matter production and nutrient contents and accumulation in the leaves of Eucalyptus grandis x E. urophylla clone; b) to evaluate the application effects in different times of two industrial residues from pulp and paper mill (cellulose sludge and dregs + grits) on tree development, wood production and nutrient accumulation in the leaves of Eucalyptus grandis x E. urophylla clone. The main conclusions were: a) the industrial residues from pulp and paper mill compost (IRPPMC) application promoted increases on height at 60 days after planting, on stem diameter and on biomass production of eucalypt plants at 120 days. The IRPPMC increase the pH value and Ca and Mg soil content. The P, K, and Na soil content also increased. The P, K, Ca e S contents and accumulation in the leaves were increased with compost application; b) industrial residues from pulp and paper mill are efficient in the liming of soil acidity. The application of 8 Mg ha-1 of dregs + grits promoted major growth on diameter and on wood production of eucalypt that 15 Mg ha-1 of activated sludge in combination with chemical fertilizer application. This dose increased Ca and Mg and the base saturation of Red Latosol (Oxisol) to adequate values to reached 40 m3 ha-1 ano-1 wood productivity, at 6,5 years, when application was in the plantation or three months later.
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19

Pujol, Arnaud. "Modélisation du procédé de compostage - Impact du phénomène de séchage." Thesis, Toulouse, INPT, 2012. http://www.theses.fr/2012INPT0015/document.

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Le compostage constitue un phénomène simple qui nécessite cependant un savoir-faire important puisque la réaction biologique est orientée par le contrôle de certains paramètres (température, oxygène, humidité) faisant intervenir de nombreux phénomènes couplés. Face à la complexité des mécanismes à étudier et dans le but d'optimiser le procédé industriel, l'utilisation d'un modèle de compostage semble donc pertinente afin de mieux comprendre les mécanismes mis en jeu, d'identifier les effets des couplages entre les mécanismes et mettre en avant certains facteurs clés ou encore comparer différents scénarios. L'état de l'art des modèles de compostage montre qu'aujourd'hui, malgré le nombre important de modèles de compostage, il n'en existe aucun capable de prédire, avec une formulation en temps et en espace, la température, la concentration des gaz (oxygène, dioxyde de carbone, diazote, …), la teneur en eau, les transferts entre phase, la dégradation du substrat, et prenant en compte les modifications d'aération. Le développement d'un nouveau modèle a donc été nécessaire pour pouvoir prédire l'évolution de ces variables et étudier leur couplage dans le procédé. Pour cela, la technique de moyenne volumique, appliquée aux équations à l'échelle du pore, a été utilisée et a permis d'obtenir un modèle de compostage à l'échelle de Darcy. Ce modèle prend en compte une phase gazeuse, une phase liquide et une phase solide. La phase gazeuse comprend quatre espèces : oxygène, dioxyde de carbone, azote, et vapeur d'eau. Dans la phase liquide, seule l'eau est considérée. Le séchage est intégré au modèle sous la forme d'un terme d'échange entre les phases gazeuse et liquide. Enfin, un modèle biologique, inclus dans le modèle de compostage, permet de prendre en compte la dégradation du substrat. Celui-ci est divisé en trois fractions : rapidement biodégradable, lentement biodégradable et inerte. Les deux premières fractions sont solubilisées, fournissant une fraction rapidement hydrolysable. Cette fraction est supposée directement consommée par les bactéries. En compostage, procédé aérobie, la dégradation de la matière organique est associée à une consommation d'oxygène et production de dioxyde de carbone, d'eau et de chaleur. L'hypothèse d'équilibre local thermique et chimique a été supposée ici. Cependant, pour l'eau, les 2 approches (Equilibre Local (EL) et Non-Equilibre Local (NEL)) ont été testées numériquement. Les résultats ont montré que lorsque σ, le coefficient d'échange de masse entre la phase gaz et la phase liquide pour l'eau, est compris dans l'intervalle [1, 4], les approches EL et NEL sont équivalentes, avec des temps de calcul moindres pour le cas NEL. Ainsi, pour toutes les simulations, une écriture NEL a été adoptée avec une valeur de σ de 2.5. Des tests ont ensuite permis de montrer la consistance du modèle. Au vu du nombre important de paramètres, une analyse de sensibilité a ensuite été réalisée afin de déterminer quels sont les paramètres qui ont l'impact le plus important sur le procédé. Ainsi, l'analyse a mis en évidence qu'il faut être prudent quant aux valeurs utilisées pour la capacité calorifique, un coefficient de l'isotherme de sorption, de nombreux paramètres du modèles biologiques (ksH, krH, µmax, Xa,0, Tmax, Topt, Xi,0, Xrb,0) et la porosité. Enfin, les résultats fournis par le modèle ont été comparés aux résultats expérimentaux obtenus à l'échelle pilote 1/1000 en usant des conditions opératoires identiques. Les essais de compostage réels ont été réalisés par Veolia Environnement Recherches et Innovation sur un mélange de biodéchets des ménages et de déchets verts
Composting may look like a simple process. However, it requires an important expertise, as the biological response is governed by the control parameters (temperature, oxygen, moisture content), involving many coupled phenomena. Given the complexity of the studied mechanisms and in order to optimize the process, using a composting model seems relevant to understand the mechanisms involved, identify the effects of coupling between these mechanisms, highlight some key factors or compare different scenarios, in order to optimize the industrial process. The state of the art of composting models in the literature shows that today, despite the large number of composting models, there is none that can predict, with a formulation in time and space, temperature, concentration of gases (oxygen, carbon dioxide, nitrogen, ...), moisture content, transfers between phases, degradation of the substrate, and take into account the changes in aeration. The development of a new model was therefore necessary to predict the evolution of these variables and study their coupling in the process. The technique of volume averaging applied to the pore scale equations has led to a composting model at the Darcy-scale. This model takes into account a gas phase, a liquid phase and a solid phase. The gas phase includes four species: oxygen, carbon dioxide, nitrogen and water vapor. In the liquid phase, only water is considered. Drying is integrated into the model as an exchange term between gas and liquid phases. Finally, the biological model, included in the composting model, allows to take into account the degradation of the substrate. It is divided into three fractions: readily hydrolysable, slowly hydrolysable and inert. The first two fractions are hydrolized, providing a readily assimilable soluble fraction. It is this fraction that is directly consumed by bacteria. In a composting process, degradation of organic matter is associated with oxygen consumption and production of carbon dioxyde, water and heat. The assumption of thermal and chemical local equilibrium was assumed in this work. However, for water, the two approaches (Local Equilibrium (LE) and Local Non-Equilibrium (LNE)) have been numerically tested. The results showed that when , the water mass exchange coefficient between gas and liquid phases, ranges from 1 to 4 s-1, the LE and LNE approaches are equivalent, with less computing time for the LNE case. Thus, for all future simulations, it was decided to adopt a LNE approach with a value of equal to 2.5 s-1. Tests were then carried out to show the consistency of the model. Given the large number of parameters, a sensitivity analysis was performed to determine the parameters that have the greatest impact on the process. This analysis showed that one must be cautious about the values used for the heat capacity, a coefficient of the sorption isotherm, many parameters from the biological model (ksH, krH, μmax, Xa,0, Tmax, Topt, Xi,0, Xrb,0) and porosity, because these are the parameters that affect mainly the process. Finally, the results provided by the model were compared with experimental results obtained at a pilot scale of 1/1000 using identical operating conditions. The composting experiments were carried out by Veolia Environment Research and Innovation with a mixture of household biowaste and green waste. The results on the 1/1000 scale pilot showed that the model is good at capturing the average change in temperature and concentration during the process. The temperature at the central point in particular is very well reproduced by the model. The same applies to the assessment of organic matter degradation. Simulations at industrial scale (1/1) have also been carried out. They have given promising results
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20

Barretto, Vitor Corrêa de Mattos. "Resíduos de indústria de celulose e papel na fertilidade do solo e no desenvolvimento de eucalipto /." Jaboticabal : [s.n.], 2008. http://hdl.handle.net/11449/105180.

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Orientador: Sérgio Valiengo Valeri
Banca: Miguel Luís Menezes Freitas
Banca: Iraê Amaral Guerrini
Banca: Rinaldo César de Paula
Banca: Mara Cristina Pessôa da Cruz
Resumo: Foram conduzidos experimentos em casa de vegetação e em condições de campo, com os seguintes objetivos: a) avaliar o efeito de doses de composto de resíduos de indústria de celulose e papel na fertilidade do solo, no desenvolvimento, na produção de matéria seca e na concentração e acúmulo de nutrientes nas folhas de um clone de Eucalyptus grandis x E. urophylla; b) avaliar os efeitos da aplicação em diferentes épocas de dois resíduos da indústria de celulose e papel (lodo ativado e não decomposto e dregs + grits), no desenvolvimento das árvores, produção de madeira e acúmulo de nutrientes nas folhas de um clone de Eucalyptus grandis x E. urophylla. As principais conclusões foram: a) A aplicação de composto de resíduos de indústria de celulose e papel (CRICP) propiciou ganhos em altura aos 60 dias após o plantio em colunas de PVC, em diâmetro do coleto e em produção de biomassa das plantas de eucalipto aos 120 dias. O CRICP resultou em aumento no valor de pH e nos teores de Ca e Mg do solo. Também elevou os teores de P, K e Na no solo. A concentração nas folhas e o acúmulo de P, K, Ca e S aumentaram com a aplicação do composto; b) Os resíduos da fábrica de celulose e papel são eficientes corretivos da acidez do solo. A aplicação de 8 t ha-1 de dregs + grits no plantio proporcionou maior crescimento em diâmetro e produção de madeira de eucalipto do que a aplicação de 15 t ha-1 de lodo ativado não decomposto. Essa dose e elevou os teores de Ca e Mg e a porcentagem de saturação por bases de Latossolo Vermelho distrófico para valores adequados para uma produtividade de madeira de 40 m3 ha-1 ano-1, aos 6,5 anos, quando aplicados no plantio ou três meses após o mesmo.
Abstract: Experiments in greenhouse and field were carried out with the objectives: a) to evaluate the effect of industrial residues from pulp and paper mill compost rates on soil fertility, on development, on dry matter production and nutrient contents and accumulation in the leaves of Eucalyptus grandis x E. urophylla clone; b) to evaluate the application effects in different times of two industrial residues from pulp and paper mill (cellulose sludge and dregs + grits) on tree development, wood production and nutrient accumulation in the leaves of Eucalyptus grandis x E. urophylla clone. The main conclusions were: a) the industrial residues from pulp and paper mill compost (IRPPMC) application promoted increases on height at 60 days after planting, on stem diameter and on biomass production of eucalypt plants at 120 days. The IRPPMC increase the pH value and Ca and Mg soil content. The P, K, and Na soil content also increased. The P, K, Ca e S contents and accumulation in the leaves were increased with compost application; b) industrial residues from pulp and paper mill are efficient in the liming of soil acidity. The application of 8 Mg ha-1 of dregs + grits promoted major growth on diameter and on wood production of eucalypt that 15 Mg ha-1 of activated sludge in combination with chemical fertilizer application. This dose increased Ca and Mg and the base saturation of Red Latosol (Oxisol) to adequate values to reached 40 m3 ha-1 ano-1 wood productivity, at 6,5 years, when application was in the plantation or three months later.
Doutor
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21

Steger, Kristin. "Composition of microbial communities in composts : a tool to assess process development and quality of the final product /." Uppsala : Department of Microbiology, Swedish University of Agricultural Sciences, 2006. http://epsilon.slu.se/200631.pdf.

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22

Rincon, Mejia Carlos Andrés. "Caractérisation des émissions gazeuses et des odeurs en compostage : étude de la corrélation entre la concentration d'odeur et la composition chimique des émissions." Thesis, Rennes 1, 2019. http://www.theses.fr/2019REN1S019/document.

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La valorisation des déchets par le compostage et la méthanisation est encouragée par les politiques de l'UE. Cependant, ces technologies de recyclage des déchets sont confrontées à un défi crucial en matière de libération et de contrôle des émissions de gaz odorants. En effet, la pollution par les odeurs est la principale cause d'opposition du public au traitement des déchets, ce qui a entraîné la fermeture et des poursuites en justice pour les unités de traitement des déchets. À l'heure actuelle, les inventaires des émissions d'odeurs et de produits chimiques pour appuyer les plans de gestion des odeurs et de la pollution atmosphérique font défaut, en raison de la complexité des évaluations des odeurs, impliquant généralement des analyses sensorielles et chimiques. L'objectif de cette thèse était donc de caractériser de manière détaillée les émissions de gaz et les odeurs lors du processus de compostage. À cette fin, les émissions d’odeurs et de polluants ont tout d’abord été étudiées au cours des différentes étapes opérationnelles du processus de compostage, à savoir le stockage, la phase active, le retournement et la maturation. Les résultats ont montré que la phase active et le retournement jouent un rôle essentiel dans les générations de nuisances olfactives causées principalement par les composés soufrés volatils (CSV). Des efforts supplémentaires ont ensuite été consacrés à la caractérisation des émissions de gaz au cours de la phase active de compostage de quinze déchets solides et du digestat, permettant ainsi de corroborer l’importance des CSV sur la production d’odeurs lors du compostage et de différencier l’impact des émissions de gaz sur les odeurs en fonction des matières premières des déchets. La dernière partie de ce travail de recherche a été consacrée à la corrélation des mesures sensorielles et chimiques, par le biais de méthodes de régression simple et multiple visant à faciliter et à renforcer le contrôle des odeurs dans les unités de traitement des déchets. Notamment, un modèle des moindres carrés partiels améliore la prévision de la concentration d'odeurs grâce à la composition chimique des gaz émis
Waste valorization through composting and methanization are actively promoted by the EU policies. However, these waste recycling technologies face a crucial challenge regarding the release and control of odorous and hazardous gas emissions. Indeed, odor pollution is the principal cause for public opposition to waste processing, leading to the closure and lawsuits for waste treatment units. Currently, there is a lack of odor and chemical emissions inventories to support odor and air pollution management plans due to the complexity of odor assessments, generally involving sensory and chemical analysis. Hence, the aim of this PhD thesis was to characterize extensively the gas emissions and odors released during the composting process. To this end, the patterns of odor and pollutant emissions were first traced throughout different operational stage of composting process, namely, storage, active phase, turning and curing. The results showed that the active phase and turning played a pivotal role in odor nuisance generations which were mainly caused by volatile sulfur compounds (VSC). Then, further efforts were focused on characterizing the gas emissions released along the composting active phase of fifteen solid wastes and digestate. The results corroborated the relevance of VSC on odors production during composting and enabled to differentiate the odor impact of gas emissions as a function of the wastes’ feedstock. The last part of this research work was devoted to correlate both, sensory and chemical measurements, through univariate and multivariate regression analysis to ease and strength odor monitoring in waste treatment units. Notably, a partial least squares model improved odor concentration prediction based on the chemical composition of emitted gases
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23

SILVA, Franciédna Maria da. "Diagnóstico e tratamento por compostagem dos resíduos sólidos orgânicos provenientes do mercado público do município de Pombal-PB." Universidade Federal de Campina Grande, 2017. http://dspace.sti.ufcg.edu.br:8080/jspui/handle/riufcg/836.

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Os resíduos agroindustriais geralmente apresentam grandes concentrações de materiais orgânicos que, se manejados de forma inadequada, podem poluir e/ou contaminar o solo, a água e o ar. Os processos de compostagem têm se estabelecido como formas eficientes de minimizar a problemática ambiental e de reduzir o volume de resíduos sólidos orgânicos descartados de forma ambientalmente incorreta. O principal objetivo deste trabalho consiste em quantificar os resíduos sólidos orgânicos do setor de hortifrúti do Mercado Público de Pombal-PB, assim como averiguar a viabilidade de produção de composto orgânico através do emprego da técnica da compostagem aeróbica em ambiente aberto. Para isso realizou-se pesagens diárias, durante quatro semanas, dos resíduos sólidos orgânicos gerados no setor de hortifrúti do Mercado Público de Pombal-PB, além do mais, foi montada uma pilha de compostagem com os resíduos orgânicos recolhidos no local de estudo e verificado o grau de maturação do composto orgânico final. O diagnóstico final resultante da pesquisa foi que são produzidos no referido setor uma média de 82,12 kg de resíduos orgânicos diariamente. Para avaliar a maturação do composto foram utilizados os parâmetros de temperatura, relação C/N, condutividade elétrica e pH. Os quais apresentaram resultados satisfatórios de maturação quando comparado com o que determina a Portaria N° 01/83 do Ministério da Agricultura, Pecuária e Abastecimento indicando que estes simples métodos são considerados seguros para verificação de processos de compostagem conduzidos em regiões sujeitas às condições semiáridas, mostrando-se eficiente para o tratamento de resíduos agroindustriais.
Agro-industrial wastes generally have large concentrations of organic materials which, if handled improperly, can pollute and / or contaminate soil, water and air. Composting processes have been established as efficient ways to minimize environmental problems and to reduce the volume of organic waste disposed of in an environmentally incorrect way. The main objective of this work is to quantify the organic solid waste of horticulture of the Public Market of Pombal -PB, as well as to investigate the viability of organic compost production through the use of the aerobic composting technique in the open environment. For this, It was performed daily weightings for four weeks of the organic solid waste generated in the horticulture sector of the Public Market of Pombal-PB, in addition, a compost pile was assembled with the organic residues collected at the study place and the degree of maturation of the final organic compound was verified. The final diagnosis resulting from the research was that an average of 82.12 kg of organic waste is produced daily. To evaluate the maturation of the compound, the parameters of temperature, C / N ratio, and electrical conductivity epH were used. It presented satisfactory maturation results when compared to that determined by Ordinance No. 01/83 of the Ministry of Agriculture, Livestock and Supply, indicating that these simple methods are considered safe for verification of composting processes conducted in regions subject to semi-arid conditions, being efficient for the treatment of agro industrial residues.
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24

Lin, Long. "Technical, Microbial, and Economic Study on Thermophilic Solid-state Anaerobic Digestion of Lignocellulosic Biomass." The Ohio State University, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=osu1500505570855855.

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25

Mačiulskas, Robertas. "Bioskaidžių atliekų kompostavimo technologinių procesų parmetrų tyrimai." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2013. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2013~D_20130621_141514-30469.

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Biologiškai skaidžių atliekų kompostavimui didelę įtaką turi anglies ir azoto santykis, priklausantis nuo kompostuojamų medžiagų rūšies. Kokybiškam kompostui pagaminti būtinos trys pagrindinės fazės: temperatūros kilimo, aukštos temperatūros ir temperatūros kritimo. Oro temperatūra buvo palanki kompostavimo procesui – vidutinė mėnesio temperatūra buvo aukštesnė arba artima daugemiačiams vidurkiams, o kritulių kiekis kompostavimo metu buvo permainingas. Komposto temperatūra priklausė nuo kompostavimo procesui būdingos fazės ir matavimo vietos – aukščiausia temperatūra (nuo 63 iki 82oC) nustatyta termofilinio proceso metu aukščiausios komposto vietos giliuosiuose sluoksniuose. Rūgštingumas komposto krūvoje kito nuo neutralaus (pH 7) kompostavimo pradžioje, termofilinės kompostavimo fazės metu tapo šarminės reakcijos (pH 8,0–8,3), temperatūros kritimo fazėje komposto rūgštingumas mažėjo iki neutralių reikšmių (pH 7,0–7,1). Optimalus kompostavimui drėgnumas (50–60%) buvo pasiektas trečią kompostavimo savaitę. Kompostavimo aikštelėse gaminant kompostą po atviru dangumi būtina atsižvelgti į meteorologines sąlygas, kurias vertinant galima parinkti tinkamą komposto krūvos vartymo dažnumą bei dirbtinio laistymo poreikį.
The carbon to nitrogen ratio, depending on the type of compostable materials, has a great impact on the composting of biodegradable waste. The three main phases necessary for obtaining the high-quality compost: temperature rise, high temperature and temperature drop. The air temperature was favourable to the composting process – the average monthly temperature was above or close to the multi-annual average, and the rainfall has been erratic during composting. The compost temperature depended on the phase and the measurement location characterized by the composting process – the highest temperature (from 63 to 82 °C) was determined during the thermophilic process in the deep layers of the highest composting place. The acidity of the compost pile varied from neutral (pH 7) at the beginning of composting, became alkaline (pH 8,0–8,3) during the thermophilic composting phase, the compost acidity decreased to neutral values (pH 7,0–7,1) during the temperature drop phase. The optimum composting humidity (50–60%) was achieved on the third week of composting. When the compost is produced in the open air composting sites, it is necessary to take account of the meteorological conditions. According to these evaluated conditions, the proper moving procedure frequency and the need for artificial irrigation can be selected for the compost pile.
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26

Ziosi, Paolo. "Nuovi processi "green" per la funzionalizzazione di composti fenolici." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2011. http://amslaurea.unibo.it/2383/.

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L’obiettivo di questo lavoro è lo studio della funzionalizzazione del fenolo mediante vie sintetiche “green”, che utilizzino quindi reagenti non clorurati e catalizzatori eterogenei, quindi facilmente recuperabili e riutilizzabili. Esistono però altri derivati fenolici di interesse commerciale, quali il catecolo, in quanto reagente di partenza per svariate molecole (tra cui appunto il DOPET) utilizzate in vari ambiti applicativi (alimentare, cosmetica, farmaceutica, agrochimica). In particolare, lo studio è stato focalizzato sulla sintesi dell’IDROSSITIROSOLO (o DOPET). Le prove effettutate con fenolo non hanno portato alla formazione del composto desiderato, ma di altri prodotti che comunque hanno interesse commerciale; ad esempio, è stato ottenuto il 2-fenossietanolo con elevata resa e selettività. Oltre al fenolo, ho studiato la reattività del metilendiossobenzene; con entrambi è stato ottenuto (seppur con basse rese) l’attacco all’anello da parte dell’etil gliossilato, formando così un intermedio potenzialmente utile per la sintesi dell’idrossitirosolo.
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Kimura, Giselle Kobata 1985. "Investigação do potencial celulolítico de bactérias oriundas de processo de compostagem." [s.n.], 2014. http://repositorio.unicamp.br/jspui/handle/REPOSIP/316714.

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Orientadores: Fabiana Fantinatti Garboggini, Suzan Pantaroto de Vasconcellos
Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia
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Resumo: Bactérias e fungos têm sido largamente explorados devido às suas habilidades em produzir uma grande variedade de enzimas, entre elas, as celulases que se destacam devido ao seu potencial em degradar materiais lignocelulósicos em açúcares fermentáveis, que podem então ser convertidos, por exemplo, em biocombustíveis. O presente trabalho visou a bioprospecção de bactérias isoladas a partir do processo de compostagem realizado pela Fundação Parque Zoológico de São Paulo (FPZSP), quanto à produção de enzimas celulolíticas, além da caracterização taxonômica das linhagens de interesse. Para tanto, os micro-organismos oriundos do processo de compostagem da FPZSP foram isolados, preservados e caracterizados macroscopicamente. Dentre as linhagens isoladas, 168 foram testadas numa triagem qualitativa para a produção de celulases, obtendo-se 135 micro-organismos com potencial celulolítico evidenciado pela formação de halos de hidrólise em meio de cultura contendo carboximetilcelulose. Destes, 10 linhagens apresentaram halos translúcidos com diâmetros entre 1,3 cm e 1,9 cm, as quais foram avaliadas quanto a atividade celulotíca em ensaios quantitativos monitorados durante 7 dias, em duas condições de pH distintas: 4,8 e 7,4. Os melhores tempos de incubação verificados foram de sete e cinco dias para os valores de pH 4,8 e 7,4, respectivamente. Em seguida, foram selecionados linhagens para os ensaios de delineamento experimental e otimização das atividades enzimáticas. No planejamento P&B, a melhor atividade celulolítica verificada foi de 3,6392 FPU/mL obtida a partir da linhagem FPZSP 143, no pH 4,8. Esta linhagem foi então selecionada e o planejamento do tipo Delineamento Composto Central Rotacional ¿ DCCR aplicado, promovendo dessa maneira, um aumento 0,4574 FPU/mL em relação ao experimento do planejamento anterior. Posteriormente, o experimento foi validado e o resultado máximo alcançado para atividade celulolítica da linhagem FPZSP 143 foi de 4,6435 FPU/mL. Cinco linhagens selecionadas com atividade celulolítica foram identificadas por análise de sequências do gene RNA ribossomal 16S como membros do gênero Bacillus, bactérias frequentemente encontradas em ambientes da compostagem e que tem sido largamente reportada como produtoras de enzimas celulolíticas. O processo de compostagem demonstrou ser um ambiente em potencial para a produção de celulases de interesse para diversos ramos da indústria, sendo os representantes do gênero Bacillus os melhores produtores de enzimas celulolíticas. Embora as bactérias tenham sido isoladas de um ambiente com pH em torno de 7,4, há um potencial para a produção de celulases em pH mais ácidos, evidenciando sua aplicabilidade em diferentes condições. Essa característica torna-se relevante quando se leva em consideração os processos industriais, onde uma condição diferente e específica é exigida em cada processo, tornando as enzimas celulolíticas oriundas de processo de compostagem grandes aliadas no desenvolvimento e otimização de processos industriais
Abstract: Bacteria and fungi have been extensively explored due to their ability to produce a variety of enzymes, including the cellulases that stand out because of their potential to degrade lignocellulosic materials to fermentable sugars, which can then be converted, for example, in biofuels. The present work aimed bioprospecting of bacteria isolated from the composting process conducted by Fundação Parque Zoológico de São Paulo (FPZSP), for the production of cellulolytic enzymes and the taxonomic characterization of strains of interest. For both, the microorganisms derived from the composting process of FPZSP were isolated, preserved and characterized macroscopically. Among the isolates, 168 were tested for production in a qualitative screening of cellulases, obtaining 135 cellulolytic microorganisms with potential evidenced by the formation of halos of hydrolysis in culture medium containing carboxymethylcellulose. These, 10 strains showed translucent halos with diameters between 1.3 cm and 1.9 cm, which were evaluated for activity in cellulolytic quantitative assays monitored for 7 days under two different pH conditions: 4.8 and 7.4. The best times of incubation recorded were seven and five days to pH 4.8 and 7.4, respectively. Then, strains for testing experimental design and optimization of enzymatic activities were selected. In Planning P&B, the best cellulolytic activity verified was 3.6392 FPU/mL obtained from FPZSP 143, at pH 4.8. This strain was selected and the DCCR applied, thus promoting an increase of 0.4574 FPU/mL compared to the previous experiment planning. Subsequently, the experiment was validated and the maximum score achieved for cellulolytic activity FPZSP 143 strain was 4.6435 FPU/mL. Five strains with cellulolytic activity were identified by sequence analysis of the 16S ribosomal RNA gene as members of the genus Bacillus, bacteria frequently encountered in composting environments and has been widely reported as producing cellulolytic enzymes. The composting process proved to be a potential environment for the production of cellulases of interest for various branches of industry, being the representatives of the genus Bacillus the best producers of cellulolytic enzymes. Although bacteria have been isolated from an environment with a pH around 7.4, there is a potential for the production of cellulases in more acidic pH, indicating their applicability in different conditions. This feature becomes important when one takes into account the industrial processes, where a different and specific condition is required in each case, making the cellulolytic enzymes derived from composting process a good allied in developing and industrial process optimization
Mestrado
Microbiologia
Mestra em Genética e Biologia Molecular
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DANIELSSON, ELLEN, and CHRISTOPHER LEKSTRÖM. "Investigation and Optimization of Small-Scale Fecal Management : As a product from dry toilet solutions in off-grid Swedish holiday homes." Thesis, KTH, Skolan för industriell teknik och management (ITM), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-299334.

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In off-grid holiday homes, alternative toilet solutions are needed. There is a wide range of dry toilet systems, where urine-diverting systems and incineration toilets are common solutions. Urine-diverting dry toilets require that users need to manage generated fecal fractions. This is often done by private composting or through municipal latrine bucket pick-ups. In this project, fecal management for holiday homes in Sweden is examined from three perspectives by (1) studying the biological phenomenon with composting and how a compost should be managed to generate rich humus, whilst minimizing greenhouse gas emissions associated with the act of composting, (2) examine current user experiences associated with latrine compost management, and (3) map out current latrine management systems, including laws and regulations. The goal was to develop a user-friendly concept for fecal management for urine-diverting toilets, based on this research. The project was carried out in collaboration with Harvest Moon, a company focused on the development of innovative and refined dry toilet systems. The project was initiated with a literature review, the examination of current fecal management systems, and interviews with composting experts and researchers. The background research showed that there is no such thing as perfect compost management since it depends on what end goals the users have. Research also showed that frequently turning the pile, increases ammonia (NH3) emissions, but reduces methane (CH4) formation. Furthermore, biochar can be added as a bulking agent to aerate the compost mass, and aid the hygienization process of such a mass, since it binds e.g., hormones. Regarding composting methods, a static passively aerated compost is not the fastest process but has the least compost mass reduction, which is desired when using it as a soil enhancer. In addition, it requires the least management. This method was therefore chosen for further development. Furthermore, since temperature and moisture are easily measured with sensors, it was deemed interesting to implement such sensors in a final concept, to alleviate management for the user. To assure that the final concept would reflect user needs and wishes, a phase of user studies was then initiated. The studies showed that users generally see latrine compost more as something to take care of, rather than as a resource, and therefore have no interest in using composted humus. The research also showed that because many municipalities require 2-year storage of the material in the composter, users experienced scheduling issues, which ultimately led to an inefficien composting system. The third perspective that was investigated, was the management systems of today and how they are regulated by laws. Each municipality has its own requirements on how latrine composts should be managed. These requirements are based on the Environmental Code, as well as Naturvårdsverket’s recommendation for the implementation of the law. Apart from the compilation of these regulations, this investigation showed that pyrolysis, as well as the centralization of hygienized feces, could be future alternatives to latrine composting and latrine pickup. But due to the short Time-to-Market, and the project's limited time scope, product development towards system innovation was deemed unrealistic within this project.  Insights from these three perspectives created a framework for the concept development phase, which was finalized with building a full-scale functional prototype. During detailed design, the concept was further developed in CAD. The final concept presented in this project is a modular, user-friendly latrine compost that can be adapted to follow different municipal regulations. It has an inner mesh that aerates the compost mass to reduce methane gas formation. The mesh is constructed with hexagonal perforated acid-proof steel. The composter has a push latch mechanism on the lid together with two gas struts, which makes it easy to open since the user only needs to push the lid once, for it to open. Temperature and moisture sensors make it easier for the user to manage their compost correctly, and a front door allows for ergonomic emptying of the finished compost humus. Future development to reduce production costs, simplify the construction, continue the CAD model development, find suitable sensors, develop product instructions as well as perform user tests with the physical prototype should be further investigated.
I fritidshus som saknar kommunalt avlopp behövs alternativa toalettlösningar. Det finns en rad olika torra toalettsystem, där urinsorterande och förbränningstoaletter är vanliga lösningar. Urinsorterande torrtoaletter kräver att användaren själv tar hand om genererade fekalier. Detta görs genom antingen privat latrinkompostering eller kommunal hämtning av latrin. I detta projekt undersöks fekaliehantering för fritidshus i Sverige från tre perspektiv genom att (1) studera biologiska fenomen i en kompost och hur en kompost ska hanteras för att få en rik humus, samt minimera växthusgasutsläpp som bildas vid just kompostering, (2) undersöka användarupplevelsen vid hantering av latrinkomposter idag, samt (3) kartlägga nuvarande system för latrinhantering, inklusive rådande lagar och förordningar. Målet med projektet var att utveckla ett användarvänligt koncept för fekaliehantering från urinsorterande toaletter, baserat på denna forskning. Projektet genomfördes i samarbete med Harvest Moon, ett företag som arbetar med att utveckla innovativa och estetiskt tilltalande torrtoalettsystem. Projektet inleddes med att studera litteratur, undersöka befintliga fekaliehanteringssystem, samt att intervjua komposteringsexperter och forskare inom området. Efter denna bakgrundsforskning kunde slutsatsen dras att det inte finns en perfekt komposthantering, då det beror på de mål som användaren har. Forskningen visade också att ju mer man vände kompostmassan, desto mer ökade utsläppen av ammoniak (NH3), dock minskade bildningen av metan (CH4). En annan insikt var att biokol kan tillsättas för att lufta, samt hjälpa till att hygienisera kompostmassan, då det binder till sig till exempel hormonrester. Gällande komposteringsmetoder så är en statisk passivt luftad kompost inte den snabbaste processen, men den leder till minst kompostreduktionen, vilket är bra om målet är att använda det komposterade materialet som jordförbättrare. Dessutom kräver det den minsta hanteringen av användaren. Denna metod valdes därför för vidareutveckling av slutkoncept. Slutligen, eftersom både temperatur och fukt lätt går att mäta med sensorer, så ansågs det intressant att implementera dessa typer av sensorer i ett slutkoncept i och med att det skulle kunna underlätta hanteringsprocessen för användaren. För att säkerställa att det slutliga konceptet skulle återspegla vad användarna behöver och önskar, inleddes sedan en fas av användarstudier. Användarstudierna visade att användare i allmänhet ser latrinkompost mer som något de måste ta hand om, än som en resurs, och har därmed inget intresse av att ta vara på det materialet som har komposterats. Studierna visade också att på grund av att många kommuner kräver två års lagring av materialet i fekaliekomposten, upplevde användare svårigheter med att få till en bra rutin kring hanteringen, vilket bidrog till att hela latrinhanteringssystemet fungerade sämre. Det tredje perspektivet som undersöktes inom projektet var hur systemen för latrinhantering ser ut idag, samt hur och av vilka lagar de regleras. Varje kommun har egna krav på hur en latrinkompost ska hanteras. Dessa krav är baserade på Miljöbalken, liksom Naturvårdsverkets rekommendationer gällande den praktiska implementeringen av Miljöbalken. Utöver sammanställningen av dessa regelverk visade studien att pyrolys, alternativt centralisering av hygieniserade fekalier, skulle kunna vara framtida alternativ till kompostering eller kommunal hämtning av latrin. Men på grund av den korta Time-to-Market för denna produkt, samt projektets begränsade tidsram ansågs produktutveckling mot systeminnovation vara orealistisk inom detta projekt. Insikter från dessa tre perspektiv bildade ett ramverk för konceptutvecklingsfasen, som avslutades med byggandet av en fullskalig funktionsprototyp. Under detaljutvecklingen fortsattes utvecklingen av konceptet i CAD. Det slutgiltiga konceptet som presenteras i projektet är en modulär, användarvänlig latrinkompost som går att anpassa till att följa olika kommunala regler. Den har en inre struktur som luftar kompostmaterialet för att minska bildandet av metangas. Strukturen består av hexagonalt perforerat syrafast stål. Komposten har en push latch mekanism på locket tillsammans med två gasfjädrar, vilket gör det enkelt att öppna eftersom användaren endast behöver trycka locket för att det ska öppnas. Temperatur- och fuktsensorer gör det lättare för användaren att hantera sin kompost korrekt, och en främre dörr möjliggör ergonomisk tömning av färdigt kompostmaterial. Framtida utveckling för att minska produktionskostnaderna, förenkla konstruktionen, vidareutveckla CAD-modellen, hitta lämpliga sensorer, utveckla användarinstruktioner, samt genomförandet av användartester med funktionsprototypen bör vidare undersökas.
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PEREIRA, Claudete Martins da Silva. "Efeito das larvas de besouro no processo de decomposi??o de esterco de coelho e produ??o de substratos org?nicos para mudas de hortali?as." Universidade Federal Rural do Rio de Janeiro, 2017. https://tede.ufrrj.br/jspui/handle/jspui/2482.

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The soil?s fertility and nutrient cycling are essential for agricultural production. Many organisms play a key role in the decomposition of organic matter present in nature. Among these organisms, more attention and research should be directed to the coprophagous insects. They transform agricultural residues in material rich in nutrients. Coleoptera families act in the fragmentation of decomposing organic matter (vegetal remains, rotten wood, straw, manure, among others), participating in the cycling of nutrients, but little is known about the humus produced by other species of the fauna of the soil beyond the earthworms. The objective of this work was to study compost from rabbit manure processed by beetle larvae under controlled conditions, and to analyze the potential of usage of this compost as substrate for lettuce seedlings production. To reach this goal, the study was accomplished in Embrapa Agrobiologia, Serop?dica (RJ), and it was divided in two phases. In the first chapter, the rabbit manure by beetle larvae and earthworms were incubated, aiming the compost production. During the course of the composting process, samples were taken at 0, 30, 60 and 90 days of incubation. In these samples the variables analyzed were: electrical conductivity (EC); pH; contents of N, P, K, Ca and Mg; and humic substances. In the second chapter the rabbit manure compost produced were evaluated as substrates for lettuce seedlings production. The following characteristics were evaluated: germination percentage, aerial part's height, number of leaves, production of fresh mass of aerial part and of the root, root volume and clod stability. The results indicated that the substrate of the cuniculture residue compost processed by cetoniinae larvae was as efficient as the substrate from vermicomposting, and the substrate commonly used in the experimental research site (Fazendinha km 47) for production of lettuce seedlings.
A fertilidade do solo e a ciclagem de nutrientes s?o fundamentais para a produ??o agr?cola. Muitos organismos exercem papel fundamental na decomposi??o da mat?ria org?nica presente na natureza. Dentre esses organismos, maior aten??o e pesquisa devem ser direcionadas aos insetos copr?fagos, por tamb?m transformarem res?duos da agropecu?ria, em material rico em nutrientes. As fam?lias de cole?pteros atuam na fragmenta??o da mat?ria org?nica em decomposi??o (restos vegetais, madeira podre, palha, estercos, entre outros), participando da ciclagem de nutrientes, por?m, pouco se conhece sobre o h?mus produzido por outras esp?cies da fauna do solo que n?o sejam as minhocas. O objetivo deste trabalho foi estudar a compostagem de esterco de coelho por larvas de besouro em condi??es controladas e analisar o potencial de uso do composto produzido como substrato para produ??o de mudas de alface. Visando alcan?ar este objetivo, este trabalho foi realizado na Embrapa Agrobiologia em Serop?dica, RJ, sendo dividido em duas etapas. No cap?tulo I, foi realizada a incuba??o de esterco de coelho por larvas de besouro e por minhocas, visando a produ??o do composto. Durante o decorrer do processo de compostagem, amostras foram coletadas aos 0, 30, 60 e 90 dias de incuba??o. Nessas amostras foram analisadas as seguintes vari?veis, condutividade el?trica (CE), pH, teores de N, P, K, Ca e Mg e subst?ncias h?micas. No cap?tulo 2, os compostos de esterco de coelho produzidos foram avaliados como substratos para a produ??o de mudas de alface. As seguintes caracter?sticas foram avaliadas: porcentagem de germina??o, altura da parte a?rea, n?mero de folhas, produ??o de massa fresca da parte a?rea e da raiz, volume de raiz e estabilidade do torr?o. Os resultados obtidos indicam que o substrato oriundo da compostagem de res?duos da cunicultura, realizada por larvas de cetoniinae, ? t?o eficiente quanto o substrato obtido atrav?s da vermicompostagem e o substrato comumente utilizado na Fazendinha km 47 para a produ??o de mudas de alface.
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Souza, Patrícia Moraes Sinohara 1988. "Estudo da influência de argilas organofílicas no processo de biodegradação de nanocompósitos de PLA e seus efeitos genotóxicos e mutagênicos." [s.n.], 2013. http://repositorio.unicamp.br/jspui/handle/REPOSIP/266645.

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Orientadores: Ana Rita Morales, Maria Aparecida Marin-Morales
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Química
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Resumo: Neste estudo, foram preparados nanocompósitos de PLA e argilas organofílicas Cloisite 20A e Cloisite 30B, pelo método de intercalação do fundido. Os materiais foram caracterizados mediante Difração de Raios-X (DRX), Microscopia Eletrônica de Transmissão (MET), Análise Termogravimétrica (TGA) e Calorimetria Diferencial Exploratória (DSC). A influência das argilas organofílicas no processo de biodegradação do PLA foi avaliada pela quantificação da taxa de mineralização do PLA e dos nanocompósitos pela norma ISO 14855-2, em condições simuladas de compostagem. Também foi avaliada a influência das argilas no processo de degradação hidrolítica do PLA, pela análise visual e monitoramento de peso molecular após os períodos de 15 e 30 dias de degradação em composto. Diante da falta de informação relacionada à ecotoxicidade de polímeros biodegradáveis, a avaliação de efeitos citotóxicos, genotóxicos e mutagênicos do composto orgânico após a degradação dos materiais foi realizada empregando o bioensaio com o organismo teste Allium cepa. Os nanocompósitos preparados apresentaram estrutura intercalada, evidenciada pela análise de DRX. As micrografias obtidas por MET permitiram a observação de diferentes níveis de dispersão, incluindo regiões esfoliadas. Foram verificadas, após a incorporação das argilas organofílicas, a redução da estabilidade térmica e o aumento do grau de cristalinidade do PLA, pelas análises de TGA e DSC, respectivamente. Com relação às medidas de mineralização, notou-se que a argila Cloisite 20A não apresentou influência significativa na biodegradação do PLA. Por outro lado, a argila Cloisite 30B levou à redução dos valores de mineralização comparados com o polímero puro, o que pode estar relacionado à atividade antimicrobiana de seu agente modificador. Na avaliação da degradação hidrolítica, notou-se que a presença de argilas organofílicas pode diminuir a taxa de degradação, possivelmente pela atuação de suas camadas como barreira. Ainda assim, mesmo no caso dos nanocompósitos, a redução do peso molecular foi significativa indicando que o processo de compostagem é favorável para a cisão de cadeia do polímero nos materiais em estudo. Na análise realizada por meio do bioensaio com o organismo teste Allium cepa, foi verificado que, após a degradação do PLA e dos nanocompósitos, o composto orgânico apresentou redução do índice mitótico e aumento da indução das alterações cromossômicas, de forma estatisticamente significativa em relação ao controle negativo do ensaio (água destilada). Pela comparação dos resultados obtidos para os nanocompósitos em relação ao polímero puro, não foram verificadas diferenças estatisticamente significativas. Os tipos de aberrações cromossômicas observadas indicam um efeito genotóxico dos materiais, possivelmente relacionado a uma ação aneugênica dos produtos de degradação do PLA
Resumo: Neste estudo, foram preparados nanocompósitos de PLA e argilas organofílicas Cloisite 20A e Cloisite 30B, pelo método de intercalação do fundido. Os materiais foram caracterizados mediante Difração de Raios-X (DRX), Microscopia Eletrônica de Transmissão (MET), Análise Termogravimétrica (TGA) e Calorimetria Diferencial Exploratória (DSC). A influência das argilas organofílicas no processo de biodegradação do PLA foi avaliada pela quantificação da taxa de mineralização do PLA e dos nanocompósitos pela norma ISO 14855-2, em condições simuladas de compostagem. Também foi avaliada a influência das argilas no processo de degradação hidrolítica do PLA, pela análise visual e monitoramento de peso molecular após os períodos de 15 e 30 dias de degradação em composto. Diante da falta de informação relacionada à ecotoxicidade de polímeros biodegradáveis, a avaliação de efeitos citotóxicos, genotóxicos e mutagênicos do composto orgânico após a degradação dos materiais foi realizada empregando o bioensaio com o organismo teste Allium cepa. Os nanocompósitos preparados apresentaram estrutura intercalada, evidenciada pela análise de DRX. As micrografias obtidas por MET permitiram a observação de diferentes níveis de dispersão, incluindo regiões esfoliadas. Foram verificadas, após a incorporação das argilas organofílicas, a redução da estabilidade térmica e o aumento do grau de cristalinidade do PLA, pelas análises de TGA e DSC, respectivamente. Com relação às medidas de mineralização, notou-se que a argila Cloisite 20A não apresentou influência significativa na biodegradação do PLA. Por outro lado, a argila Cloisite 30B levou à redução dos valores de mineralização comparados com o polímero puro, o que pode estar relacionado à atividade antimicrobiana de seu agente modificador. Na avaliação da degradação hidrolítica, notou-se que a presença de argilas organofílicas pode diminuir a taxa de degradação, possivelmente pela atuação de suas camadas como barreira. Ainda assim, mesmo no caso dos nanocompósitos, a redução do peso molecular foi significativa indicando que o processo de compostagem é favorável para a cisão de cadeia do polímero nos materiais em estudo. Na análise realizada por meio do bioensaio com o organismo teste Allium cepa, foi verificado que, após a degradação do PLA e dos nanocompósitos, o composto orgânico apresentou redução do índice mitótico e aumento da indução das alterações cromossômicas, de forma estatisticamente significativa em relação ao controle negativo do ensaio (água destilada). Pela comparação dos resultados obtidos para os nanocompósitos em relação ao polímero puro, não foram verificadas diferenças estatisticamente significativas. Os tipos de aberrações cromossômicas observadas indicam um efeito genotóxico dos materiais, possivelmente relacionado a uma ação aneugênica dos produtos de degradação do PLA
Abstract: In this study, nanocomposites of PLA with organoclays Cloisite 20A and Cloisite 30B were prepared by the melt intercalation method. The materials were characterized by X-ray diffraction (XRD), Transmission Electron Microscopy (TEM), Thermogravimetric analysis (TGA) and Differential Scanning Calorimetry (DSC). The influence of organoclays in the biodegradation process of PLA was assessed by quantifying the rate of mineralization according to ISO 14855-2, in simulated composting conditions. The influence of clays on the hydrolytic degradation process of PLA was also investigated by visual analysis and monitoring of molecular weight after periods of 15 and 30 days of degradation in organic compost. Given the lack of information related to ecotoxicity of biodegradable polymers, the assessment of citotoxic, genotoxic and mutagenic effects of the organic compost, after the materials degradation, was carried out using the bioassay with Allium cepa as test organism. The nanocomposites presented an intercalated structure, evidenced by XRD analysis. The TEM micrographs allowed the observation of different dispersion levels, including exfoliated regions. After incorporation of organoclays, a reduction of thermal stability and an increasing in the degree of crystallinity of the PLA were observed by TGA and DSC analysis, respectively. In respect to the mineralization, it was noted that the clay Cloisite 20A showed no significant influence on the biodegradation of PLA. On the other hand, the clay Cloisite 30B led to decreased levels of mineralization compared to the polymer, which may be related to an antimicrobial activity of its modifying agent. In the evaluation of hydrolytic degradation it was verified that the presence of organoclays can decrease the rate of degradation possibly by the action of its layers as a barrier. Nevertheless, even in the case of nanocomposites, the molecular weight reduction was significant, indicating that the composting process is favorable to the chain scission of the polymer in the studied materials. In the analysis performed by the bioassay using the test organism Allium cepa, it was verified that after degradation of PLA and the nanocomposites, the organic compost showed an reduction of the mitotic index and an increasing in the induction of chromosomal abnormalities. These results were statistically significant in relation to negative control (distilled water). By comparing the results obtained for the nanocomposites in relation to pure polymer, there were no statistically significant differences. The types of chromosomal aberrations observed indicate a possible genotoxic effect of materials, which may be related to an aneugenic action of the degradation products of PLA
Abstract: In this study, nanocomposites of PLA with organoclays Cloisite 20A and Cloisite 30B were prepared by the melt intercalation method. The materials were characterized by X-ray diffraction (XRD), Transmission Electron Microscopy (TEM), Thermogravimetric analysis (TGA) and Differential Scanning Calorimetry (DSC). The influence of organoclays in the biodegradation process of PLA was assessed by quantifying the rate of mineralization according to ISO 14855-2, in simulated composting conditions. The influence of clays on the hydrolytic degradation process of PLA was also investigated by visual analysis and monitoring of molecular weight after periods of 15 and 30 days of degradation in organic compost. Given the lack of information related to ecotoxicity of biodegradable polymers, the assessment of citotoxic, genotoxic and mutagenic effects of the organic compost, after the materials degradation, was carried out using the bioassay with Allium cepa as test organism. The nanocomposites presented an intercalated structure, evidenced by XRD analysis. The TEM micrographs allowed the observation of different dispersion levels, including exfoliated regions. After incorporation of organoclays, a reduction of thermal stability and an increasing in the degree of crystallinity of the PLA were observed by TGA and DSC analysis, respectively. In respect to the mineralization, it was noted that the clay Cloisite 20A showed no significant influence on the biodegradation of PLA. On the other hand, the clay Cloisite 30B led to decreased levels of mineralization compared to the polymer, which may be related to an antimicrobial activity of its modifying agent. In the evaluation of hydrolytic degradation it was verified that the presence of organoclays can decrease the rate of degradation possibly by the action of its layers as a barrier. Nevertheless, even in the case of nanocomposites, the molecular weight reduction was significant, indicating that the composting process is favorable to the chain scission of the polymer in the studied materials. In the analysis performed by the bioassay using the test organism Allium cepa, it was verified that after degradation of PLA and the nanocomposites, the organic compost showed an reduction of the mitotic index and an increasing in the induction of chromosomal abnormalities. These results were statistically significant in relation to negative control (distilled water). By comparing the results obtained for the nanocomposites in relation to pure polymer, there were no statistically significant differences. The types of chromosomal aberrations observed indicate a possible genotoxic effect of materials, which may be related to an aneugenic action of the degradation products of PLA
Mestrado
Ciencia e Tecnologia de Materiais
Mestra em Engenharia Química
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31

Aquino, Lucilene de. "Subsídios para implantação do processo de compostagem em município de pequeno porte : estudo de caso em Corumbataí-SP." Universidade Federal de São Carlos, 2012. https://repositorio.ufscar.br/handle/ufscar/4338.

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University of São Carlos, 2012. Composting is one of the oldest processes of recycling organic waste. Despite being an environmentally appropriate treatment, their use is still little known regarding the management of municipal solid waste (MSW). This study aimed to investigate the management of MSW in Corumbataí - SP. For this purpose gravimetric characterization of MSW were performed, and composting alternatives applicable to the municipality of Corumbataí were analyzed. The study also sought to assess the perception inhabitants of the city regarding the subject matter, as well as their acceptance regarding previous separation of compostable organic waste (COW). Initially a survey on the management from the MSW was implemented. Two gravimetric characterizations were carried out, being the first in June and the other in December. In order to choose the composting alternative the following aspects were analyzed: the amount of organic waste; the availability and accessibility of the area; the existing infrastructure, equipment, labor and impacts on the environment. Questionnaires were applied to each of the families, from house to house, in order to evaluate the existing selective collection program, as well as the amount of knowledge they had about composting. The level of their acceptance in doing separation of organic household waste was also evaluated. Results: We found that the public power is adapting its MSW in a way environmentally responsible, and the selective collection program has shown good efficiency. Through gravimetric characterizations performed in the months of June and December, we obtained a high percentage of organic material (80%), identifying thus the viability of implementing a composting process. We found that the public power is adapting its MSW in a way that is environmentally correct, and the selective collection program has shown a good efficiency. About gravimetric characterizations performed in the months of June and December, we obtained a high percentage of organic matter (80%), identifying the availability of implementing a composting process. It was suggested the use of manual system of rotated furrows because of simple technology, constituted from equipment of easy maintenance and low cost. The research performed with the population found that 100% of respondents participate on the selective collection and had no doubt about the process of waste unbundling. In addition, garbage collection services provided by municipal employees were rated as excellent and good in 89% of the interviewed. About composting, 51% of the respondents had knowledge about the subject, as well as waste that could be composted. Another important finding of this study was to observe that 98% of the interviewed are disposed to separate organic waste for composting. The statement of a significant percentage of organic matter present in the composition of the MSW from Corumbataí means to provide a final destination for the most noble organic waste, with composting as an alternative for the treatment of them. Since the practice of selective collection is incorporated into the habits of the population, there is a positive perspective on the introduction of a third separation for composting organic waste (ROC) as observed in the research about the knowledge and opinion of locals about composting. In this sense it was suggested that the manual system using plowed furrows because of the simplified technology, comprising equipment for easy maintenance and low cost. The survey conduct among the population found that 100% of the respondents participate in the selective collection and have no doubts about the process of separating the trash. Furthermore, 89% of respondents the garbage collection services provided by municipal employees were rated as excellent or good. As for composting, 51% of respondents had knowledge about it, and knowing identify which waste could be composted. Another important fact observed in the study was that 98% of respondents are willing to separate organic waste for composting.
A compostagem é um dos mais antigos processos de reciclagem de resíduos orgânicos. Apesar de ser um tratamento ambientalmente adequado, sua utilização ainda é pouco difundida no que se refere à gestão municipal dos resíduos sólidos urbanos (RSU). O presente trabalho de pesquisa teve como objetivo investigar a gestão dos RSU no município de Corumbataí-SP. Para isso, foi realizada caracterização gravimétrica dos RSU e foram analisadas alternativas de compostagem aplicáveis ao município. O estudo também buscou avaliar a percepção da população quanto ao assunto em questão, bem como sua aceitação da separação prévia dos resíduos orgânicos compostáveis (ROC). Inicialmente foi realizado um levantamento da Gestão e Gerenciamento dos RSU existentes no município. Em seguida, foram realizadas duas caracterizações gravimétricas, sendo uma no mês de junho e outra em dezembro. Para escolha da alternativa de compostagem, foram analisados os seguintes aspectos: quantidade de resíduos orgânicos; disponibilidade de área e acessibilidade; infraestrutura; equipamentos; mão de obra e impactos no entorno. Posteriormente foram aplicados questionários nas unidades domiciliares de Corumbataí, com o objetivo de avaliar o programa de coleta seletiva, bem como o conhecimento dos entrevistados sobre compostagem e o nível de aceitação deles para fazer a separação prévia dos resíduos orgânicos domiciliares. Constatou-se que o poder público vem gerenciando seus RSU de forma ambientalmente correta, e o programa de coleta seletiva existente tem apresentado boa eficiência. Das caracterizações gravimétricas realizadas nos meses de junho e dezembro, obteve-se um percentual elevado de matéria orgânica (80%), identificando-se, portanto, a viabilidade da implantação de um processo de compostagem. Nesse sentido, foi sugerida a utilização do sistema manual de leiras revolvidas, em virtude da tecnologia simplificada, constituída de equipamentos de fácil manutenção e de baixo custo de aquisição. A pesquisa realizada com a população constatou que 100% dos entrevistados participam da coleta seletiva e não têm dúvidas quanto ao processo de separação dos RSU. Além disso, para 89% dos entrevistados os serviços de coleta de lixo prestados pelos funcionários municipais foram avaliados como ótimo ou bom. Quanto à compostagem, 51% dos entrevistados apresentaram conhecimento sobre o assunto, além de saberem identificar quais dos resíduos poderiam ser compostados. Outro dado importante observado na pesquisa foi que 98% dos entrevistados estão dispostos a separar os resíduos orgânicos para a compostagem. A constatação da presença de um percentual significativo de matéria orgânica na composição dos RSU de Corumbataí justifica proporcionar uma destinação final mais nobre para esse tipo de resíduo. A compostagem é sugerida como uma alternativa para o tratamento dos mesmos. Existe uma perspectiva positiva quanto à introdução da separação de resíduos orgânicos compostáveis (ROC), uma vez que a prática da coleta seletiva encontra-se incorporada no hábito da população, conforme constatado na pesquisa de conhecimento e opinião dos moradores sobre a compostagem.
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32

Fialho, Lucimar Lopes. "Caracterização da matéria orgânica em processo de compostagem por métodos convencionais e espectroscópicos." Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/75/75132/tde-14042008-153813/.

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A produção de resíduos orgânicos tem aumentado em anos recentes e uma alternativa para o seu aproveitamento é o processo de compostagem, no qual se desenvolvem reações bioquímicas para estabilização do material que estão diretamente associadas com a humificação da matéria orgânica. Considerando a complexidade das transformações no processo de humificação e a importância de se conhecer com maior precisão estas reações e as características dos materiais gerados, foi proposto neste trabalho um estudo detalhado do processo de compostagem. A combinação de métodos convencionais e técnicas espectroscópicas permitiu o monitoramento contínuo da compostagem, de diferentes resíduos orgânicos. Para execução dos experimentos foram montadas 6 leiras (L) de 3,6 m3 com os seguintes resíduos: poda de árvores, esterco bovino fresco, bagaço de laranja, torta de filtro e solução de ácido pirolenhoso (como possível catalisador do processo). O monitorado foi realizado por 7 meses com medidas diárias de temperatura, controle semanal do teor de umidade e coletas mensais das amostras para extração de ácidos húmicos e análises químicas. Foram observadas as fases típicas da temperatura em todas as leiras, exceto na L1 (constituída apenas de poda de árvores). Na fase termofílica a temperatura atingiu os 60 o C e esta fase permaneceu por, aproximadamente, 90 dias. Este também foi o tempo necessário para a estabilização da relação da capacidade de troca catiônica pelo teor de carbono do composto (CTC/C), que alcançou valores acima de 2,2 mmolc g-1 . As análises de macro e micronutrientes evidenciaram o potencial fertilizante dos compostos produzidos, cujos valores, para alguns elementos, estão acima dos limites exigidos pela Instrução Normativa no 23 do Ministério de Agricultura, Pecuária e Abastecimento. Já nas análises espectroscópicas foram encontrados índices de estabilização a partir dos espectros de fluorescência de luz UV - Vis. Estes apresentaram boa correlação com a razão C/N e os radicais livres orgânicos do tipo semiquinona, detectados por Ressonância Paramagnética Eletrônica. As correlações dos índices com a razão C/N mostraram que este último parâmetro tem limitação para monitorar a compostagem, pois a partir de 60 dias a relação C/N estabiliza, ainda na fase termofílica do processo, enquanto que os índices espectroscópicos continuam variando, indicando que o processo não se estabilizou completamente. Dentre as informações obtidas por fluorescência, foi possível identificar reações de transformação de moléculas orgânicas mais simples para estruturas mais complexas, detectadas através da diminuição de intensidade das bandas de emissão em comprimentos de onda menores (em torno de 300 nm) com simultâneo aumento da intensidade em regiões de maiores comprimentos de onda (próximos de 400 nm). Este comportamento também foi observado nos espectros de absorção UV - Vis. A partir dos dados de Ressonância Magnética Nuclear (RMN de 13 C) foi possível evidenciar a decomposição de estruturas como carboidratos, polissacarídeos e grupos alquil, assim como um aumento das estruturas aromáticas, durante o processo de humificação. Assim através da combinação das análises por métodos convencionais e espectroscópicos foram propostos indicadores analíticos mais sensíveis para o monitoramento e a caracterização da compostagem de resíduos orgânicos.
The production of organic residues has increased in recent years and an alternative to their recycling is the composting process, where various biochemical reactions are developed for the material stabilization. These reactions are directly associated with organic matter humification. Considering the complexity of the transformations occurred during the humification process and the importance of knowing these reactions and the characteristics of the produced materials more precisely, this work has proposed a detailed study of the composting process. The combination of conventional methods and spectroscopic techniques allowed the continuous composting assessment and monitoring from different organic residues. Six piles (P) of 3.6 m3 were assembled using the following residues: garden trimming, fresh cattle manure, orange pomace, filter cake and pyroligneous acid solution (used as possible catalyst of the process). The process was monitored for 7 months with daily measurements of temperature, weekly moisture control and monthly collection of samples for humic acid (HA) extraction and chemical analyses. Typical phases of temperature in all piles were observed, except for P1 (composed only garden trimming). In the thermophilic phase the temperature reached 60 o C and this phase remained for about 90 days. This was also the time necessary for stabilization of cation exchange capacity and total carbon ratio (CEC/C), which reached values above of 2.2 mmolc g-1 . The macro- and micronutrient analyses showed the fertilizer potential of the produced composts. Concentration values for same elements are above those required by Normative Instruction number 23 of the Brazilian Ministry of Agriculture Livestock and Food Supply. As a result of the spectroscopic analyses, stabilization indices were obtained from fluorescence spectra of UV-Visible light. These indices showed good correlation with C/N ratio and with the semiquinone-type free radical, detected by Electron Paramagnetic Resonance (EPR). The correlation of the indices with C/N ratio showed that the latter parameter has limitation to monitor the composting, because after 60 days the C/N ratio stabilizes and this occurs during the thermophilic phase, while the spectroscopic indices continue to change, which is an indicative that the process was not completely stabilized. Among several observations by fluorescence of UV-Visible light it was possible to identify transformation reactions of simpler organic molecules to more complex structures, which were detected by decrease in emission band intensity in shorter wavelengths (near 300 nm) with simultaneous increase in band intensity in longer wavelengths (near 400 nm). This behavior was also observed in the UV - Visible absorption spectra. It was possible to show the decomposition of carbohydrate type structures, polysaccharides and alkyl groups and the increase in aromatic structures, by 13 C Nuclear Magnetic Resonance (13C NMR), during humification process of the organic residues. Therefore, more sensible analytic indicators were proposed for monitoring and characterization of the composting of organic residues through the combination of conventional and spectroscopic methods.
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33

Montanari, Silvia. "Sinergia di processi chimico-fisici per la riqualificazione di acque contaminate da composti organici." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2015. http://amslaurea.unibo.it/9260/.

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L’acqua è una delle risorse critiche del pianeta e l’acqua dolce accessibile all’uomo rappresenta meno dell’1% delle risorse idriche; da questi numeri si capisce quanto siano importanti la prevenzione dell’inquinamento ambientale e i processi di depurazione delle acque reflue. A partire dagli anni ’70, grazie anche al miglioramento delle tecniche analitiche, sono iniziati monitoraggi degli inquinanti nelle acque superficiali e sotterranee e sono state riscontrate concentrazioni di inquinanti, i cui effetti di tossicità cronica sull’uomo e l’ecosistema non sempre sono trascurabili. Inoltre si è rilevato che alcune molecole di sintesi sono difficilmente biodegradabili e non sono mineralizzate con i trattamenti convenzionali di depurazione; perciò l’Unione Europea ha emanato delle direttive per preservare le risorse idriche in cui è contenuto un elenco di sostanze prioritarie, per le quali sono stati fissati gli standard di qualità ambientale. Nel 2013 è stata anche istituita una watch list che contiene dieci sostanze sulle quali raccogliere dati di monitoraggio ambientale e effetti sugli ecosistemi. Di qui la ricerca costante di nuovi trattamenti di depurazione delle acque, tra i quali i processi di ossidazione avanzata attirano molto interesse perché promettono di mineralizzare i composti bio-recalcitranti senza produrre fanghi da smaltire o sottoprodotti pericolosi. Oggetto della presente tesi sperimentale, svolta presso il Consiglio Nazionale delle Ricerche, nell’Istituto per la Sintesi Organica e la Fotoreattività, è stato lo studio della de-gradazione e mineralizzazione di una miscela di cinque molecole (diclofenac, carbama-zepina, triton X-100, benzofenone-3, benzofenone-4), scelte per le diverse caratteristiche chimico-fisiche, utilizzando radiazione ultravioletta e ultrasuoni, in presenza di biossido di titanio come fotocatalizzatore o perossido d'idrogeno come additivo per produrre radicali idrossile e avviare catene di reazioni ossidative. A partire dai fenomeni fotochimici o fotocatalitici così ottenuti, eventualmente assistiti da ultrasuoni, sono stati studiati gli effetti delle variazioni dei parametri operativi sulla degradazione dei componenti della miscela e sono stati valutati i consumi energetici della strumentazione prototipale per unità di massa del contaminante degradato. La parte sperimentale è stata preceduta da un’accurata ricerca bibliografica riguardo gli effetti di tossicità degli inquinanti ritrovati nelle acque, la legislazione europea ed italiana in materia ambientale e delle acque e i processi di ossidazione avanzata.
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34

Marzo, Aldo. "L’abbattimento delle emissioni di composti organici volatili in un colorificio." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2021.

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L’oggetto del presente lavoro di tesi è stato la riduzione della concentrazione di composti organici volatili (COV) nelle correnti gassose emesse ai camini di uno stabilimento per la produzione di vernici, al fine di portarne il valore al di sotto del limite ammesso dalle norme di legge. La classe dei composti organici volatili comprende numerosi composti chimici con proprietà fisiche e chimiche differenti, ma accomunati da un'elevata volatilità. I COV possono provenire da fonti naturali o da processi umani. Si è stimato che le fonti antropogeniche emettano complessivamente a livello mondiale circa 142∙10E+06 ton/anno di carbonio sotto forma di composti organici volatili, provenienti dai derivati del petrolio, dai prodotti delle combustioni, dalle vernici e dai rivestimenti; nello specifico la produzione mondiale di vernici e di rivestimenti è stimata pari a 12∙10E+09 litri/anno e in essa i COV antropogenici trovano largo utilizzo come solventi. Per contenere l’esponenziale aumento dei COV in atmosfera, vengono istituite regolamentazioni sempre più stringenti, che costringono le industrie di vernici a intervenire sui loro processi al fine di ridurre l’emissione di COV. Gli interventi e le tecnologie convenzionali per abbattere i COV nei processi industriali sono la filtrazione per adsorbimento con il filtro a carboni attivi o la degradazione termica con il post-combustore. Queste tecnologie hanno alti costi operativi e di manutenzione, e non intervengono risolvendo il problema alla radice, bensì sono impiegate in coda al processo produttivo, trascurando le inefficienze della gestione dei COV a monte. Nello stabilimento oggetto del presente lavoro di tesi l’abbattimento delle concentrazioni di COV al camino è stato ottenuto intervenendo direttamente sul processo produttivo, consentendo non solo di soddisfare i necessari requisiti di protezione ambientale, ma anche di ottenere un notevole risparmio economico, a causa della minore perdita di solventi.
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35

Novais, Tiago de Morais Faria. "Execução de um pátio de compostagem em solo-cimento: análises de suas propriedades e influência no processo de compostagem." Universidade Federal de Viçosa, 2011. http://locus.ufv.br/handle/123456789/3821.

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This dissertation evaluated the viability of implementation a soil-cement made composting yard as its capacity of impermeability and its influences on the biological degradation process of municipal waste. The reduction of costs of a Recycling and Composting Plants is a lack to small municipalities on their recycling programs. As the composting yard represents a meaningful quote of investments of Recycling and Composting Plant implementation, this innovation is proposed to minify its costs. A composting yard was made and an analysis of the composting process of organic matter on its surface was carried out to compare with the same process realized on a conventional non-structural concrete yard. The soil- cement yard was made on top of a draining layer to verify its tightness and covered with a thin daub of cement in order to increase its life cycle and durability. Resistance analysis to compression of soil-cement and parameters of the organic matter to be composted were evaluated as pH, fixed carbon, volatile matter, moisture, temperature, fecal coliform and heavy metals (Hg, Cu, Cr, Cd, Zn, Pb e Ni). Also, the rainwater colected from the yard surface was collected and evaluated as it turbidity, pH, fecal coliform, temperature and heavy metals. At the end of this study, was made a budget to compare the costs reduction of a Recycling and Composting Plant implementation choosing a soil-cement made yard. About the tightness, the soil cement yard made showed preventing rainwater permeation. Its simple compression resistance was evaluated as satisfactory, with 4,9 MPa by the 28th day. The composting processes on both yards were carried out during the active degradation period to compare effects. The costs of implementation of soil-cement yard made were approximately 30,9% lesser than the conventional yard. Considering the total Reclycling and Composting Plant budget, the reduction of costs was about 7,7% of the investment. Key-words: Municipal solid waste, composting yard, soil-cement, waste treatment.
Avaliou-se, neste trabalho, a viabilidade de execução de um pátio de compostagem em solo-cimento quanto a sua estanqueidade e de influências no processo de degradação biológica de resíduos sólidos. A redução de custos na execução de Unidades de Triagem e Compostagem (UTC s) é uma necessidade para os municípios com menor capacidade de investimentos. Como o pátio de compostagem representa uma significativa parcela do investimento total de uma obra de UTC, a execução deste pátio em solo- cimento é uma proposta de redução nos custos de execução. Foi executado um pátio em solo-cimento, analisando a compostagem de material orgânico em sua superfície, comparando os resultados com os obtidos em um pátio de concreto não estrutural. O pátio de solo-cimento foi executado com uma fina camada de argamassa para o aumento de sua vida útil. Todo o pátio foi executado sobre uma estrutura drenante a fim de verificar a estanqueidade do mesmo. Análises de resistência à compressão simples de corpos-de-prova do solo-cimento foram conduzidas assim como análises de pH, sólidos fixos e voláteis, umidade, temperatura, coliformes fecais e metais pesados (Hg, Cu, Cr, Cd, Zn, Pb e Ni) da matéria orgânica utilizada no processo de compostagem. As águas pluviais drenadas pela superfície do pátio foram coletadas e realizadas análises de turbidez, pH, coliformes fecais, temperatura e os metais pesados analisados no material orgânico. Ao final do trabalho, uma estimativa orçamentária foi feita com o intuito de comparar a redução de custos na implantação de uma UTC ao se optar pelo pátio em solo- cimento Quanto à estanqueidade, o pátio em solo-cimento se mostrou eficiente, não permitindo a infiltração de águas pluviais. Sua resistência à compressão simples se mostrou satisfatória, com 4,9 MPa aos 28 dias de cura. A compostagem em ambos os pátios foi conduzida durante a fase ativa de degradação para efeitos comparativos do processo. Os custos de implantação do pátio em solo-cimento foram de, aproximadamente, 30,9% menos em relação ao em concreto. Palavras-chave: Resíduos sólidos, pátio de compostagem, solo-cimento, tratamento de resíduos.
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36

Amgarten, Deyvid Emanuel. "Análise computacional da diversidade viral presente na comunidade microbiana do processo de compostagem do Zoológico de São Paulo." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/95/95131/tde-14072017-161226/.

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O estudo da diversidade viral em amostras ambientais tem se tornado cada vez mais importante devido a funções-chave desempenhadas por esses organismos. Estudos recentes têm fornecido evidências de que vírus de bactérias (bacteriófagos) podem ser os principais determinantes em ciclos biogeoquímicos de grandes ecossistemas, além de atuarem no fluxo de genes entre comunidades ambientais e na plasticidade funcional das mesmas frente a estresses ambientais. Neste trabalho, propomos a investigação e caracterização da diversidade viral presente em amostras de compostagem através de abordagens não dependentes e dependentes de cultivo. Na primeira abordagem, coletamos amostras seriadas de uma unidade de compostagem do zoológico de São Paulo para realização de sequenciamento metagenômico. O conjunto de sequências gerado foi extensivamente minerado (data-mining) para a produção de resultados de diversidade e abundância de táxons virais ao longo do processo de compostagem. Adicionalmente, procedemos com a montagem e recuperação de sequências virais candidatas a genomas completos e/ou parciais de novos vírus ambientais. Os dois protocolos computacionais utilizados para a mineração de dados encontram-se definidos e automatizados, podendo ser aplicados em quaisquer conjuntos de dados de sequenciamento metagenômico ou metatranscritômico obtidos através da plataforma Illumina. A segunda abordagem correspondeu ao isolamento e caracterização de novos fagos de Pseudomonas obtidos de amostras de compostagem. Três novos fagos foram identificados e tiveram os seus genomas sequenciados. A caracterização genômica desses fagos revelou genomas com alto grau de novidade, insights sobre a evolução de Caudovirales e a presença de genes de tRNA, cuja função pode estar relacionada com um mecanismo dos fagos para contornar o viés traducional apresentado pela bactéria hospedeira. A caracterização experimental dos novos fagos isolados demonstrou grande potencial para lise e dissolução de biofilme da cepa Pseudomonas aeruginosa PA14, conhecida como agente causador de infecções hospitalares em pacientes imunodeprimidos. Em suma, os dados reunidos nesta dissertação caracterizam a diversidade presente no viroma da compostagem e contribuem para o entendimento dos perfis taxonômico, funcional e ecológico do processo.
The study of the viral diversity in environmental samples has become increasingly important due to key-roles that are performed by these organisms in our ecosystems. Recent publications provide evidence that viruses of bacteria (bacteriophages) may be key-players in biogeochemical cycles of large ecosystems, as oceans and forests. Besides, they may also be determinant in the genes flux among populations and in the plasticity of the communities face to environmental stresses. In this work, we propose the investigation and characterization of the viral diversity in composting samples through non-culturable and culturable-dependent approaches. In the first approach, we sampled a composting unit from the Sao Paulo Zoo Park in different time points and proceeded with metagenomic sequencing. The dataset generated was extensively mined to provide results of diversity and abundance of viral taxa through the composting process. Additionally, we proceeded with the assembly and retrieval of candidate sequences to partial or/and complete viral genomes. The two computational protocols were automatized as pipelines and can be applied to any metagenomic dataset of illumina reads. The second approach refers to the isolation and characterization of new Pseudomonas phages obtained from composting samples. Three new phages were identified and their genomes were sequenced. A detailed characterization of these genomes revealed high degree of novelty, insights about evolution of tailed-phages and the presence of tRNA genes, which may be related to a mechanism to bypass host translational bias. The experimental characterization of the new phages demonstrated great potential to lyse bacterial cells and to degrade Pseudomonas aeruginosa PA14 biofilms. In short, the data presented in this dissertation shed light to the composting virome diversity, as well as to the functional and ecological profiles of viruses in the composting environment.
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37

Sacchetti, Valentina. "Effetti della composizione e del processo fermentativo sulle proprieta antiossidanti di prodotti fermentati a base di Kamut." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2021. http://amslaurea.unibo.it/23272/.

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Il grano KAMUT®, ed in generale tutti i cereali antichi, costituiscono un importante fonte di composti bioattivi e sostanze benefiche per la salute. Il crescente interesse per questo tipo di cereale è legato alla sua capacità di adattamento a coltivazioni in agricoltura biologica e a basso input, all’utilizzo come cereale integrale, al maggior valore nutritivo e alle svariate proprietà funzionali della sua farina che la rendono adatta ai processi di fermentazione e panificazione. La biodisponibilità dei composti bioattivi nei prodotti integrali a base KAMUT® dipende da una serie di fattori, tra cui: tipo di fermentazione, genotipo, fase di maturazione, preparazione dell’impasto e processo di cottura. Il KAMUT® è considerato un substrato idoneo sia per la fermentazione industriale sia, in particolar modo, per la fermentazione a lievitazione naturale. Quest’ultima consente di migliorare la bioaccessibilità dei nutrienti, ottenere un profilo antiossidante in grado di conferire protezione da infiammazioni e da stress ossidativo, e apportare un profilo aromatico caratteristico del prodotto dato il complesso di composti volatili che produce. Al fine di ottenere un miglioramento delle caratteristiche qualitative degli impasti di KAMUT® sono stati utilizzati ceppi specifici di Lactobacillus; tra questi, i ceppi L. paracasei I1 e L. plantarum hanno ottenuto prestazioni più elevate. L’effetto antiossidante ed antinfiammatorio dei componenti del KAMUT® è stato dimostrato sia da studi in vitro che in vivo. Nel complesso, nonostante siano state messe in evidenza le maggiori proprietà benefiche del grano KAMUT® rispetto ai grani moderni, sono necessari ulteriori e più estesi studi che approfondiscano la tematica. Inoltre, è fondamentale considerare nel corso degli studi gli effetti additivi, sinergici o antagonisti tra i diversi componenti dell’alimento, dal momento che il grano KAMUT® è il risultato dell’effetto sinergico di tutti gli ingredienti.
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DORDONI, ROBERTA. "Ottimazione dei processi di chiarificazione di vini bianchi mediante l'impiego di bentonite." Doctoral thesis, Università Cattolica del Sacro Cuore, 2011. http://hdl.handle.net/10280/963.

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La presente tesi di dottorato ha riguardato la valutazione di differenti campioni di bentoniti sodiche. Le attività pianificate sono state indirizzate a comprendere l’interazione dei suddetti materiali con proteine a diverso peso molecolare naturalmente contenute nei vini bianchi. Ulteriori indagini hanno riguardato l’eventuale impatto delle argille testate sui composti aromatici di origine varietale e fermentativa dei mosti e/o dei vini. I risultati sottolineano il ruolo chiave esercitato dal “fattore matrice”: oltre al tipo di vino, prima di pianificare un trattamento di fining, devono essere considerate anche la tipologia e la dose di bentonite da utilizzare.
This PhD thesis dealt with the evaluation of different sodium bentonite samples. The planned activities were aimed to understand the interactions between bentonites and different molecular weight proteins naturally contained in white wines. Further investigations were related to the impact of the clays on varietal and fermentative aroma compounds of musts and/or wines. Results underscore the key role exerted by the “matrix factors”: bentonite dose and typology and wine style have to be carefully considered before planning a fining treatment.
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Toma, Raul Shiso. "Efeito da aplicação de composto orgânico sobre o processo de encrostamento e a recuperação de solos degradados pela erosão hídrica." Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/11/11140/tde-17072008-175406/.

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A geração de resíduos orgânicos juntamente com a erosão, são dois grandes problemas ambientais mundiais. São responsáveis pela redução da produtividade agrícola e pelos altos impactos ambientais. O presente projeto teve como objetivo a utilização de resíduos orgânicos gerados na agropecuária, na forma de composto orgânico, para a recuperação de áreas degradadas pela erosão hídrica. Foram avaliados os efeitos de quatro doses de composto (0, 20, 40 e 100 Mg.ha-1) na recuperação dos solos degradados por erosão. Somado a isto foi também avaliado o efeito da dose de composto sobre o processo de encrostamento superficial do solo. O projeto foi composto por dois experimentos, um com a ausência da erosão e o outro com presença de erosão (remoção de uma camada de 50 cm de solo), sendo realizados concomitantemente na mesma área. O delineamento experimental usado para cada experimento foi o inteiramente casualizado com 4 tratamentos (0, 20, 40 e 100 Mg.ha-1) e 4 repetições. Para o monitoramento da recuperação do solo e do processo de encrostamento em função das diferentes doses de composto, amostras deformadas e indeformadas de solo foram coletadas para análises físicas e químicas de rotina, para medidas da densidade do solo, para confecção de curvas características de retenção de água, e para análises micromorfológicas e de imagens. No campo foram realizados o monitoramento da chuva, da condutividade hidráulica e da infiltração de água no solo. Ficou claro que com o aumento da dose de composto orgânico aplicado no solo, melhor era a condição química do mesmo. Os valores dos elementos aumentavam conforme a dose de composto era também aumentada. A ação da matéria orgânica no solo colaborou com um aumento na retenção de água no solo a partir das doses de 40 e 100 Mg.ha-1. Esta melhor retenção de água favoreceu juntamente com a química, o crescimento das culturas no período seco garantindo assim uma maior produção de matéria seca das culturas implantadas, principalmente na dose de 100 Mg.ha-1. Com o aumento da porosidade do solo ao longo do tempo estudado em todas as doses de composto aplicado, a densidade do solo diminuiu onde o composto estava presente, se tornando mais constante em altas doses seus valores. A condutividade hidráulica do solo foi reduzida ao longo dos dois experimentos para todas as doses de composto aplicado. Essa redução pode ser explicada pelo aumento do encrostamento superficial do solo ao longo do tempo principalmente nas doses de 0 e 20 Mg.ha-1, dificultando a infiltração de água no solo. Portanto, a aplicação de altas doses de composto orgânico aceleram a recuperação dos atributos químicos e físicos do solo, assim como colaboram na redução da formação de vesículas nas crostas superficiais e diminuem os efeitos do impacto das gotas de chuvas na formação do encrostamento.
The generation of organic waste along with soil erosion are two major environmental problems worldwide. They are responsible for the reduction of agricultural productivity and high environmental impacts. The objective of this dissertation is the use of organic waste generated in agriculture, in the form of organic compost, for the recovery of degraded areas by water erosion. The effects of four doses of compost (0, 20, 40 and 100 Mg.ha-1) in the recovery of degraded soils by erosion, was tested. Added to this, the effect of the dose of compost on the process of soil surface crusting surface was also tested. The project was composed of two experiments, one with no erosion and the other with erosion (removal of a layer of 50 cm of soil), conducted concurrently in the same area. The experimental design for each experiment was completely randomized with 4 treatments (0, 20, 40 and 100 Mg.ha-1) and 4 replications. For the monitoring of the recovery of soil and the process of crusting according to the different doses of compost, deformed and undeformed soil samples were collected for routine physical and chemical analyses soil density evaluation, determination of the characteristic water retention curve, and for micromorphological and image analysis. In the field, rain, hydraulic conductivity and soil water infiltration were monitored. It was clear that with the increasing doses of organic compost used in the soil, the chemical condition meliorated. The content of the nutrients increased as the dose of compost was also increased. The action of organic matter in the soil collaborated with an increase in its water retention mainly for doses of 40 and 100 Mg.ha-1. This better water retention helped, together with the chemical recuperation, in the growth of the crops in the dry season thereby ensuring a higher dry matter yield, mainly in the dose of 100 Mg.ha-1. The increasing soil porosity over time observed in all doses of compost applied, led to a decrease in the soil density. The hydraulic conductivity of the soil was reduced in both experiments for all the applied compost doses. This reduction can be explained by the increase of the soil crusting process over time, especially in the doses of 0 and 20 Mg.ha-1, hampering the water infiltration in the soil. Therefore, the application of high doses of organic compost accelerates the recuperation of the chemical and physical attributes of the soil. It also collaborates in reducing the formation of vesicles in the superficial crust and decreases the effects of the impact of the raindrops on the crust formation.
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40

Medeiros, Angela Carolina de. "AVALIAÇÃO DO PROCESSO DE CO-COMPOSTAGEM DE LODO DE TANQUE SÉPTICO UNIFAMILIAR E RESÍDUOS SÓLIDOS ORGÂNICOS." Universidade Estadual da Paraíba, 2009. http://tede.bc.uepb.edu.br/tede/jspui/handle/tede/2162.

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This study had the object of evaluating the influence of the frequency of aeration and the quantity of structural material in the process of co-composting of sludge from house septic tanks with residual organic solids. The research was carried out at the Experimental Station for the Biological Treatment of Sewage (EXTRABES), in the city Campina Grande, Paraiba during the period from August 2008 to July 2009. To mount the experimental system of co-composting sludge was collected from the house septic tanks in the district of Malhada da Roça, in the small town of São João do Cariri, situated in the semi-arid region of the state of Paraiba. The residual organic solids were collected from the Paraiba Company for Food and Agricultural Services (EMPASA), Campina Grande, PB. The experimental system comprised a new treatment of co-composting of sludge from house septic tanks with residual organic solids using a process of turning over, with a frequency of 1, 2 and 3 times per week with proportions of porous material of 4 and 8%. The monitoring period was for 112 days and weekly samples were collected for physic-chemical analysis and parasite counts. The turning frequency did not have a significant effect on the transformation of total volatile solids during the treatment period. The quantity of added structural material directly influenced the efficiency of the transformation of dry mass which was inversely proportional to the percentage of structural material added. The process of co-composting showed efficient removal of helminthes eggs. The compost produced met the legal requirements in relation to the quantities of macronutrients. The efficiency of the co-composting system showed two distinct phases: namely rapid during the first 35 days and a slow subsequent phase. The kinetic constants for biodegradation were determined from adjusted exponential equations, and showed higher values during the rapid phase and values approximately ten times lower during for the slow phase.
O trabalho teve objetivo de avaliar a influência da freqüência de aeração e quantidade de estruturante no processo de co-compostagem de lodo de tanque séptico unifamiliar e resíduos sólidos orgânicos. A pesquisa foi realizada na Estação Experimental de Tratamento Biológico de Esgoto (EXTRABES), na cidade de Campina Grande-PB, durante o período de Agosto de 2008 a Julho de 2009. Para a montagem do sistema experimental de co-compostagem foram coletados lodos de tanques sépticos unifamiliar no distrito de Malhada da Roça, Município de São João do Cariri, localizado no semi-árido paraibano. Os resíduos sólidos orgânicos foram coletados na Empresa Paraibana de Alimentos e Serviços Agrícolas (EMPASA), Campina Grande-PB. O sistema experimental foi constituído de nove tratamentos de co-compostagem de lodo de tanque séptico unifamiliar e resíduos sólidos orgânicos, realizando o processo de reviramento com freqüência de uma, duas e três vezes por semana e percentagem de estruturante de 0, 4 e 8%. O monitoramento do sistema experimental foi realizado durante 112 dias, e semanalmente eram coletadas amostras para realização de análises físico-químicas e parasitológicas. A freqüência de reviramento não apresentou influência significativa na transformação de STV nos tratamentos estudados. O material estruturante influenciou diretamente no processo, de modo que o comportamento da eficiência de transformação de massa seca foi inversamente proporcional ao percentual de estruturante. O processo de cocompostagem mostrou-se eficiente na remoção de ovos de helmintos. O adubo produzido atendeu aos requisitos da legislação, com relação à quantidade de macronutrientes. O desempenho do sistema de co-compostagem permitiu visualizar duas fases distintas: rápida nos primeiros 35 dias e fase lenta nos dias subsequentes. As constantes cinéticas de biodegradação foram determinadas a partir de equações exponenciais ajustadas, apresentando valores maiores na fase rápida, e valor aproximadamente dez vezes menor na fase lenta.
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Massukado, Luciana Miyoko. "Desenvolvimento do processo de compostagem em unidade descentralizada e proposta de software livre para o gerenciamento municipal dos resíduos sólidos domiciliares." Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/18/18139/tde-18112008-084858/.

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A presente pesquisa teve como objetivos desenvolver o processo de compostagem dos resíduos sólidos, previamente separados na origem e, propor um software livre para o gerenciamento municipal de resíduos sólidos domiciliares. O processo de compostagem se desenvolveu em uma unidade descentralizada experimental, localizada no município de São Carlos, com capacidade para tratar 4 t/mês de resíduos orgânicos. A análise da qualidade do composto foi realizada segundo parâmetros físicos, químicos e microbiológicos. Os resultados indicaram que o composto atende à maioria dos limites estabelecidos pela legislação brasileira, principalmente, com relação à concentração de metais pesados (Cd < 0.5, Pb = 1.3, Cr = 17.4, As < 0.5, Hg < 0.5, Se < 0.5 e Ni = 0.8, em mg/kg) e presença de organismos patogênicos. No entanto, quando esse composto foi submetido a ensaio ecotoxicológico teste agudo em minhocas da espécie Eisenia andrei - constatou-se toxicidade do mesmo, com taxas de mortalidade significativas (P<0.05) a partir da concentração de 16% de composto em solo artificial tropical(TAS), o que significa uma dose de 60 t/ha. A alta condutividade elétrica do composto (CE = 7,48 mS/cm) foi considerada a responsável pela toxicidade do mesmo, uma vez que os teores de metais pesados estiveram muito abaixo dos limites estabelecidos pela legislação. O software livre desenvolvido nesta pesquisa foi denominado SIMGERE - simulação para a gestão de resíduos sólidos - que permite ao usuário simular a vida útil do aterro sanitário a partir da proposição de diferentes cenários de gerenciamento de resíduos sólidos domiciliares. Como estudo de caso aplicou-se o SIMGERE para estimar a vida útil do novo aterro sanitário de São Carlos/SP a partir da simulação de 27 cenários, nos quais foram alteradas as taxas de produção per capita de resíduos (0; 0,5 e 1,0% a.a.), a eficiência da central de triagem (0,5 e 10% a.a) e da unidade compostagem (0,5 e 10% a.a). Os resultados das simulações apontaram uma vida útil variando entre 17 (pior cenário) e 20 anos (melhor cenário). Pode-se inferir pelas simulações que a variação na produção per capita teve maior influência na vida útil do aterro do que a variação na eficiência da central de triagem e da unidade de compostagem. Esse resultado reforça a importância de se realizar investimentos em campanhas de conscientização da população para reduzir a geração de resíduos.
This research aims to develop a household waste composting in a decentralized composting plant and propose open source software for the municipal solid waste management. The composting process was developed in an experimental decentralized plant in São Carlos, with a 4 tons/month capacity. The output compost quality analysis was made according to physical, chemical and microbiological parameters. Result showed that the compost fulfills most of the safety limits required by the brazilian law (IN 27/2006, MAPA), especially in respect with heavy metal concentrations (Cd < 0.5, Pb = 1.3, Cr = 17.4, As < 0.5, Hg < 0.5, Se < 0.5 e Ni = 0.8, em mg/kg) and the presence of pathogens. However, when this compost was submitted to an ecotoxicological test acute test with Eisenia andrei earthworms one verified toxicity in samples with significant mortality (p<0.05) on compost concentrations over 16% in a tropical artificial soil, meaning a 60 ton/ha dose. High electrical conductivity (CE = 7,48 mS/cm) was considered responsible for the compost toxicity. An open source software called SIMGERE - simulation for solid waste management - was developed and allows the user to simulate landfill lifespan from the suggestion of different solid waste scenarios. The software was used to estimate the lifespan of the new landfill in São Carlos/SP from 27 scenarios where waste production rate per capita were changed (0; 0,5 and 1% per year). It was also changed the efficiency of sorting facilities (0,5 e 10%) and composting plants (0,5 e 10%). The results of these simulations showed that the lifespan can range from 17 years (worst case scenario) to 20 years (best case scenario). One can infer by the simulations that changes in the production per capita had a greater influence on the landfill lifespan than changes in efficiency of sorting facilities and of composting plants. This result shows the importance to invest in awareness campaigns to reduce waste.
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42

Cavallo, Martina. "Valorizzazione della frazione organica dei rifiuti solidi urbani tramite liquefazione idrotermale e digestione anaerobica: monitoraggio del processo biologico e caratterizzazione chimica dei composti organici idrosolubili." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2020.

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Questo elaborato si basa su uno studio effettuato in collaborazione con l’istituto di ricerca ENI-Donegani durante il quale si è esaminata la possibilità di trattare attraverso un processo biologico accoppiato, anaerobico-aerobico, le acque derivanti dal trattamento idrotermale (HTL, hydrothermal liquefaction) della frazione organica del rifiuto solido urbano (FORSU). Lo studio si è incentrato sulla resa del processo in termini di biogas prodotto e sull’ identificazione dei composti presenti all’interno del refluo da trattare. Per il monitoraggio del processo biologico sono state condotte le seguenti analisi: GC-TCD (gas cromatografia-detector a conduttività termica) per l’identificazione della composizione del biogas; estrazione e analisi in GC-MS (gas cromatografo-spettrometro di massa) per l’identificazione degli acidi grassi volatili prodotti nel processo di digestione anaerobica; analisi del pH, dell’ammoniaca e del COD (Chemical Oxygen Demand) delle sostanze organiche disciolte. Per la caratterizzazione chimica dei composti organici idrosolubili non volatili stata effettuata una derivatizzazione, tramite sililazione, dei flussi di entrata e di uscita al reattore, con successiva analisi in GC-MS. L’analisi quantitativa è stata effettuata grazie al metodo dello standard interno. Dai risultati dello studio e stato riscontrato un problema di inibizione dei metanogeni e dei microrganismi aerobi con una maggiore produzione di VFAs rispetto a biometano. Tale inibizione è stata attribuita principalmente alla variabilità del sistema NH3/VFAs/pH ed alla presenza di molecole inibenti nel refluo acquoso (HTL-WW). Vista la maggiore produzione di VFAs potrebbe essere interessante valutare la separazione di questi composti ad alto valore economico utilizzati nelle industrie chimiche per la produzione di vernici, gomma, materie plastiche, pesticidi, e conservanti alimenti.
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43

Cavina, Mattia. "Processo multistadio per la valorizzazione di acque di vegetazione dalla produzione di olio di oliva: recupero di composti fenolici, digestione anaerobica e valutazione economico-ambientale." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2019. http://amslaurea.unibo.it/17970/.

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Olive mill wastewaters (OMWs) are an environmental concern due to their high organic load and phytotoxic activity, but they are rich of phenolic compounds (PCs) and their recovery is interesting, thanks to their antioxidant and antimicrobial properties. The anaerobic digestion of the resulted dephenolized water (D-OMW), in order to produce methane and to obtain a treated water for irrigation, is an additional advantage. The goal of this work is to propose an integrated process of PCs recovery through an adsorption step (evaluated also with LCA-CBA) and anaerobic digestion of D-OMW. Two resins (XAD16 and IRA958 in OH form) were compared with semicontinuous-flow adsorption/desorption tests conducted in a 1-m packed column. A test was also conducted with a mixed bed of the two resins. The D-OMWs resulted from the previous tests were then used for anaerobic digestions. The LCA confirms the possible decreasing of the environmental impact of the process through the addition of an anaerobic digestion step for the production of irrigation water from dephenolized OMW, while the PC market price needed for a positive business case is reasonable. The results indicate that the proposed PC adsorption/desorption technology, if integrated with an anaerobic digestion step, which has an optimal methane yield, represents a promising solution for the treatment and valorisation of OMWs.
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44

Lima, Geraldo Francisco Corrêa Alves de. "O gerenciamento de resíduos sólidos urbanos em Rio Pomba – MG na visão de atores sociais que participaram do processo." Universidade Federal de Goiás, 2014. http://repositorio.bc.ufg.br/tede/handle/tede/4421.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
Around 60% of Brazilian municipalities, especially the smaller sized cities, still dispose of solid urban waste in inadequate manner. The solution to this issue represents a great challenge to the public sector. In Zona da Mata, in the southeast region of Minas Gerais, where the city of Rio Pomba is located, several observers attribute the problem of solid urban waste to the lack of attention from the public sector. In some of the municipalities in the region, even basic waste collection is not implemented. The citizen in these municipalities, by lack of alternatives or resources, is habituated to simply throwing away their waste directly into the waters of rivers in the region. Thus, the investigation proposed in this research has the objective of analyzing the process of solid urban waste management in the Rio Pomba municipality, from 1999 to 2012. The viewpoint of the stakeholders involved in the process is taken, considering the before and after of the implementation and successive deactivation of the Waste Recycling Plant in the city. The methodology used is based on a quantitative study. The following instruments were used to collect data: semi-structured interviews (recorded through audio and transcribed for analysis), visits, field reports, and relevant documents. Twelve key stakeholders were interviewed, among which public managers that currently have or had in the past some type of link to the waste disposal process in Rio Pomba. To analyze the data, three categories of analyses were identified, denominated respectively: "Knowledge", "Accountability" and "Environmental Education". In the conclusion, an analysis of solid waste management in Rio Pomba is presented. We observe fragility in this process, specially because of the discontinuity of several one-off activities that were disconnected from a systemic approach.
Cerca de 60% dos municípios brasileiros, principalmente os de pequeno porte, ainda dispõem seus resíduos sólidos urbanos de maneira inadequada. A solução desse problema representa um grande desafio para a gestão pública. Na Zona da Mata, região sudoeste de Minas Gerais, onde se encontra a cidade de Rio Pomba, diversos relatos atribuem o problema dos resíduos sólidos urbano à falta de atenção da administração pública. Em alguns municípios da região não havia sequer coleta de lixo. Por falta de opção ou recursos, o cidadão costuma lançar seus dejetos diretamente nas águas de córregos e rios da região. Em virtude disso, a investigação proposta neste trabalho tem como objetivo fazer uma análise sobre o processo de gestão de resíduos sólidos urbanos no município de Rio Pomba no período de 1999 a 2012 a partir da visão de atores sociais envolvidos nesse processo considerando o que havia antes, e o que sucedeu após a implantação e posterior desativação da “Usina de Reciclagem de Lixo”. A metodologia utilizada recai sobre um estudo qualitativo. Foram utilizados como instrumentos para coleta de dados: entrevistas semiestruturadas (gravadas por meio de áudio eletrônico e, posteriormente, transcritas para análise), visitas in loco, diário de campo e documentos. Foram entrevistados doze atores sociais, entre os quais gestores públicos, que têm ou tiveram algum vínculo significativo com a problemática do lixo e sua destinação final em Rio Pomba. Para analisar os dados foram identificadas três categorias de análise denominadas de “Conhecimento”, “Responsabilização” e “Educação Ambiental”. Na conclusão é apresentada uma análise sobre aspectos da gestão dos resíduos sólidos em Rio Pomba, na qual observamos fragilidade manifestada, sobretudo, pela descontinuidade de várias ações que foram pontuais e desconectadas de uma visão sistêmica.
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45

Poletti, Marco. "La gestione innovativa del frantoio: ottimizzazione delle variabili di processo per il miglioramento qualitativo del prodotto." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2021.

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Questo elaborato di tesi aveva l’obiettivo di realizzare uno storico in grado di fornire a “Terra di Brisighella” strumenti utili alla gestione del proprio frantoio. Sono stati utilizzati nove oli vergini di oliva, ottenuti con diversi tempi di gramolatura, valutando questa variabile sulle loro caratteristiche compositive e sensoriali. L’attività sperimentale ha riguardato gli aspetti di seguito riportati: analisi della frazione fenolica, per valutare la legittimità di apposizione in etichetta dell'indicazione salutistica “polifenoli nell’olio d’oliva” (Regolamento (UE) 432/2012); studio delle condizioni di processo più idonee all’ottenimento di un prodotto con le caratteristiche qualitative ricercate, con particolare attenzione alle condizioni di gramolatura; evoluzione qualitativa del prodotto durante la conservazione. Per tutti i campioni la concentrazione in composti fenolici è risultata alta, in relazione al limite minimo a cui fa riferimento il regolamento e ciò ha legittimato la possibilità di apporre il claim salutistico. Il tempo di gramolatura ideale a promuovere la ripartizione dei composti fenolici nell’olio è risultato di 30 minuti, mentre per favorire il rilascio nello spazio di testa dei composti volatili è risultato 15-25 minuti. Lo stoccaggio ha provocato ai campioni un significativo decadimento qualitativo, principalmente a quelli caratterizzati da un minor contenuto fenolico. La filtrazione è stato considerato un trattamento necessario a preservare la qualità dei campioni durante la conservazione. Sono stati ottenuti risultati molto interessanti utilizzabili come base di partenza per la sperimentazione anche nell’annualità 2020-2021. Nella successiva campagna olivicola le prove verranno effettuate nell’intervallo di tempi di gramolatura compreso tra 20 e 30 minuti, si estenderà la sperimentazione su un altro prodotto commerciale della Cooperativa e si studierà la shelf-life di campioni commerciali filtrati ed imbottigliati.
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46

Lin, Chun-Yu, and 林純伃. "The Study of Low Odor Food Waste Composting process." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/06270287978914933388.

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碩士
國立高雄海洋科技大學
海洋環境工程研究所
99
This research is aiming to minimize odor emission during the food waste composting processes via the method of pH control. During the food waste composting process, nitrogen element will convert into NH3 or CH3NH2 in an anaerobic condition, thus cause the odor emission problems. It is known that NH3 is a base material, can be neutralized by the organic acid during the initial stage of the composting processes. As the pH increasing during the composting processes, the neutralization capability decreased as well. When the pH is approaching the neutral condition (pH=7), the NH3 will not be soluble in the water content of the compost, and will emit freely as NH3 gas, thus cause the odor problem. Our creative approach is to use organic acid (such as acetic acid) to adjust the compost pH to maintain at the pH5, pH6, pH7 level; and to compare which situation is the best for NH3 odor emission control. And to select the best pH turning point for setting up the future odor control standard operation procedure (SOP). Also to optimize the organic acid usage amount to evaluate the most feasible approach. During the study, total accumulated amount of NH3 emitted will monitored via the NH3 automatic monitoring instrument and via NH3 dragger tube. During the experiment period, the pH, temperature, ammonia and moisture content of each pile were continually monitored. The result showed: (1) increase mature compost quantity are more, the initial of pH value is higher; The NH3 gas produces early, so the NH3 had the time also early to finish; When pH<6, NH3 not yet Obvious emission, therefore detect the NH3 value not to be high; When pH rise to between 6~7, NH3 starts to emission obviously; when pH>7, NH3 emission to increase suddenly; When pH>8.0, the NH3 emission achieves the peak, this time is odor most serious stage in compost system ; Then NH3 emission has to drop, when compost complete mature, NH3 no longer produces, the pH value also returns drops to between 7.0~7.5. May judge change of the pH value be possible initially to do is the NH3 stink emissions against system the optimal parameter. (2) the fficiency of NH3 control eexperiment knowing, has not increased comparison of the acetic acid to pile, gauges NH3 early, and NH3 presents the crest value to need the date number to be few, the NH3 emission is also high. After that increases (the fat pile of pH value according to the fat pile of increase acetic acid content to be low), NH3 presents density of the crest value to be low, and presents time of the crest value also to postpone. The entire journey ammonia delivers the total quantity respectively is in order pH5 (9,732ppm) < pH6 (17,007ppm) < pH7 (22,493 ppm) < has not adjusted control of the pH value to pile (28,102 ppm). NH3 has the decrement result respectively is when pH5 reduce NH3 enission 65%, pH6 reduce NH3 enission 40%, and when pH7 reduce NH3 enission 20%. If our proposed ideal is to be supported for practical application, we still have to make sure that the added organic acid or mineral acid should not affect on the bioactivity of the compost degradation bacteria; thus, a complete stabilization of the compost can be approached. If this approach can be approved, the absorbed NH3 will indeed enhance the N fixation rate, thus, increase the N fertilization content. And this expectation can be easily proved by total N analysis of the final compost products. Finally, if the proposed ideal can be proved, we can not only minimize the NH3 odor emission problems, but also increase the compost fertilization. This will become a perfect win-win solution to the food waste composting industry.
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47

Fraser, Bud S. "An investigation of in-vessel composting process control strategies." Thesis, 1997. http://hdl.handle.net/2429/6493.

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Composting provides environmental benefits including an alternative method for organic waste disposal, as well as improving soil fertility. However poor compost quality and odour emission are often significant problems in the composting industry. Composting process control can potentially help reduce both of these problems. In spite of the recent development of a number of process control strategies, very few direct comparisons have been made between these, particularly in terms of compost quality and odour emission. To help address this need, a series of experiments was conducted to evaluate the effects of several in-vessel process control strategies on compost quality and odour emission. The strategies tested focussed on aeration control, which in turn affects temperature, oxygen, and moisture, the most important conditions for microbial activity. Fixed aeration (Beltsville method), temperature feedback (Rutgers method), oxygen feedback, and combined temperature/oxygen feedback were tested. A modified algorithm based on temperature, called linear temperature feedback, was also developed and tested. Results showed that while many quality parameters such as C:N ratio and organic matter loss were similar between process control methods, compost oxygen was maintained more consistently using oxygen feedback or linear temperature feedback methods; these methods may also provide greater nitrification and lower phytotoxicity. Linear temperature feedback is preferable to oxygen feedback in that it does not require oxygen sensors to operate. Odorous gas (including ammonia) mass emission rates were typically found to increase with higher aeration rates, such as those used to limit temperature, though the gas concentration was lower. For maximum retention of nitrogen, adequate supply of readily biodegradable carbon in the feedstock is vital.
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48

Soares, Micaela Alexandra da Rocha. "Eggshell valorisation by co-composting process for environmental applications." Doctoral thesis, 2016. http://hdl.handle.net/10316/30045.

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Tese de doutoramento em Engenharia Química, apresentada ao Departamento de Química da Faculdade de Ciências e Tecnologia da Universidade de Coimbra
Nowadays, the European guidelines boost the concept of “circular economy” where the focus is to reuse, repair, refurbish and recycle existing materials and products. As a result, the waste can be turned into a resource with benefits to the economy and environment. In this scope, composting is a waste management option that can promote the retrieval of waste organic matter and nutrients, which can be tailored to obtain a product for suppressing soil deficiencies. This work aimed to evaluate the feasibility of co-composting industrial eggshell waste (ES) with other agro wastes (potato peel, grass clippings and rice husks), to obtain an added value product. For attaining this key motivating factor, co-composting was assessed at three levels: i) process performance, ii) end-product quality and iii) added-value of the final product (compost). In lab-scale self-heating reactors with forced aeration, several mixtures were composted. Firstly, a starting composting mixture of organic rich wastes was selected based upon its biological activity. Then, increasing quantities of industrial eggshell (inorganic material) were added up to 60% (w/w, wet basis). The influence of N-rich sources was also investigated. In these experiments, temperature and oxygen uptake rate were the main process variables monitored and conventional physical, chemical and stability parameters were also evaluated. Principal components analysis was used to unravel the main relationships structuring the variability associated to the composting experiments. Finally, added-value of the composting end-products obtained was appraised, in terms of sorption capacity and immobilisation of metals in soil. In this ambit, the fractionation of metals was determined. Globally, results showed that co-composting of industrial eggshell waste is feasible to fulfil the pathogen-killing criteria (70ºC, for 1 hour), when an N-rich source was present. At higher level of ES (60% w/w, wet basis) pathogen-killing temperatures were atained, but aerobic biological activity was hindered by some physical properties of the mixture, namely due to high density and low water holding capacity. Eggshell composting product (CES) was stable, non-phytotoxic and can be an effective liming material with intrinsic properties for in situ remediation of soil contaminated with lead and zinc.
Hoje em dia, as diretrizes europeias fomentam o conceito de "economia circular", onde o foco é a reutilização, reparação, recuperação e reciclagem de materiais e produtos em fim de vida. Como resultado, os resíduos podem ser transformados em recursos com benefícios para a economia e meio ambiente. Neste âmbito, a compostagem é uma opção de gestão de resíduos que pode promover a recuperação de matéria orgânica e nutrientes através da obtenção de um produto adequado para suprimir determinadas deficiências do solo. Este trabalho teve como objetivo avaliar a aplicabilidade da co-compostagem de resíduos industriais de casca de ovo (RCO) com outros agro-resíduos (casca de batata, aparas de relva e casca de arroz), de forma a obter um produto de valor acrescentado para remedição ambiental. Para o efeito, o processo de co-compostagem foi avaliado a três níveis: i) desempenho operacional, ii) qualidade do produto final e iii) valor acrescentado do produto final (composto) para aplicação ambiental. Em reatores laboratoriais de auto-aquecimento e com arejamento forçado foram testadas misturas com várias composições, de forma a selecionar uma mistura de base tendo como critério a atividade biológica. Posteriormente, quantidades crescentes de casca de ovo industrial (material inorgânico) foram adicionadas até um máximo de 60% (p/p, base húmida). Adicionalmente foi também investigada a influência de fontes ricas em azoto no desenvolvimento do processo foi também investigada. Nestas experiências laboratoriais, a temperatura e a taxa de consumo de oxigénio foram os principais variáveis monitorizadas, tendo sido avaliados diversos parâmetros convencionais de natureza física e química, bem como a estabilidade biológica. A análise de componentes principais (PCA) foi utilizada para mostrar as principais relações que estruturam a variabilidade associada aos testes de compostagem. O valor acrescentado dos produtos finais de compostagem obtidos foi avaliado, em termos de capacidade de sorção e potencial de imobilização de metais no solo. Neste âmbito, foram realizados testes descontínuos de sorção e o fracionamento de metais no solo. Globalmente, os resultados evidenciaram que a co-compostagem de resíduos industriais de casca de ovo é viável para cumprir os critérios higienização (70ºC, durante 1 h), quando uma fonte de rica em N está presente na mistura de base. No nível mais alto de incorporação de RCO (60% p/p, base húmida), o critério de higienização foi atingido, mas a atividade biológica aeróbia foi dificultada por algumas propriedades físicas da mistura, nomeadamente devido à elevada densidade bulk e à baixa capacidade de retenção de água. Os produtos finais de compostagem ricos em RCO são estáveis, não-fitotóxicos e podem ser utilizados como material de calagem com propriedades intrínsecas para remediação in situ de solos contaminados com chumbo e de zinco.
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49

Hsu, Ting-en, and 徐挺恩. "Effect of food waste composition on the composting process." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/32297530510764431407.

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碩士
國立高雄第一科技大學
環境與安全衛生工程所
95
ABSTRACT The thesis was to provide a method to predict process parameters of food waste composting such as maturity time, volatile mater loss, final pH value, carbon/nitrogen losses. The synthetic food wastes of various compositions made of animal foods were composted in a small laboratory sized composter to study the effect of composition on the composting process. Multivariate regression analysis and response surface methodology were applied to obtain the predictive models and contour curves. Ternary plots were made to show the effects graphically. Experimental results showed that the composition significantly affected the maturity time, the nitrogen loss (%), the final pH value, and the loss of volatile matter. Protein content, in general, was the dominating factor for the maturity time. The higher the protein content is, the shorter the maturity time. When the protein in the substrate was up to 67.63%, only 72 hours were required for maturity and the final pH value was 9.02. The oil was more difficult to decompose than the protein and the carbohydrate. The higher the oil content was, the slower the slower the process. When the oil content was up to 39.35%, 386 hours were required for maturity. The highest carbohydrate test run (run A) with 89% of carbonate needed 240 hours to reach maturity.
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50

Lee, Po-Heng, and 李伯亨. "Mass and energy balances of sewage sludge composting process." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/47658203923206411395.

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碩士
國立交通大學
環境工程所
91
In order to correspond with the promotion of living standard in Taiwan, as a result the industry, and commerce are highly prosperous. Then the quantity of sewage sludge which is discharged by families and factories is increasing gradually, and that causes the decrease of the environment quality. Therefore, the government is going to raise the rate of drainage for 3% per year to improve this actual environmental problem. However, the huge sludge comes into being due to the sewage disposal, which will be a potential troublesome problem as well. In order to dispose of the huge sewage sludge quantity that increases year by year, and to satisfy the residents who strictly request a better environment due to the raise of environmental protection consciousness, sludge compost process will be the profitable solution that fits hygienic and economic. This study constructs the mathematical formula of mass and energy balance, which is required for a design of a compost plant. It is necessary to: 1) infer and set up the energy and mass growth and decline the conditions during the composting process. 2) apply these data to estimate the suitability and accuracy of this formula, so as to be the reference for designing compost plant in the future, 3) decrease the sludge treatment and disposal costs, 4) accelerates the compost reaction and improve the quality of maturity compost. The compost experiment uses the sludge cake made by Ming-Sheng sewage disposal plant as a source; then mix the wood dust and compost products with different water content. Two 110 L capacity Lab-Scales differentiate into shut type and open type. Three lots, totally six experiments are conducted. In the beginning, the moisture percentage of the sludge compost in each lot is modified to 55%, 60% and 65% each. One 13 m3 capacity Pilot-Scale is located inside the sewage disposal plant in Pa-Li, and one batch experiment is proceeded there. The moisture percentage of the sludge compost is changed to 65% in the beginning. Six sludge compost experiments are started off in the 110 升 capacity Lab-Scale. The outcome indicates the compost process runs better in the open system. The temperature is 3° to 5° hotter than the shut system, which proves the more compost touches with atmosphere, the better reaction compost process reveals. Furthermore, in the open system, the compost process reacts the best when the moisture possesses 55% in the beginning. It decreases 9.6 Kg in total. Secondly comes 60% and 65%. During the six sludge compost experiments proceeded in 13 m3 capacity Pilot-Scale, it totally decreases 4.59 ton. The temperature remains 55oC for over 15 days, which has already achieved the standard of U.S.EPA 305 regulation. To calculate 7 sets experiment data based on mass and energy balance, the average peak error in mass energy balance and energy balance is 46% and 9.62% each. In addition, to quote one set of vegetable compost data conducted by Kaohsiung First Science and Technology University into mass and energy balance. The average peak error in mass energy balance and energy balance appears 34.7% and 6.24%.
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