Rozprawy doktorskie: „Waste Disposal Systems”

1

Wilson, Bruce Gordon. "Systems modelling of municipal solid waste collection operations /". *McMaster only, 2001.

Style APA, Harvard, Vancouver, ISO itp.

2

Bonnett, Timothy Charles. "A systems view of the nuclear waste dilemma". Master's thesis, This resource online, 1991. http://scholar.lib.vt.edu/theses/available/etd-01202010-020205/.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

3

Harvey, Penelope. "The material politics of waste disposal - decentralization and integrated systems". Pontificia Universidad Católica del Perú, 2012. http://repositorio.pucp.edu.pe/index/handle/123456789/79784.

Pełny tekst źródła

Streszczenie:

Este artículo, y el anterior «Encuentros y desencuentros del estado local y regional en la gestión integrada de los residuos sólidos. Una tarea pendiente en el Valle Sagrado» de Teresa Tupayachi, son trabajos complementarios sobre la gestión de residuos sólidos en el valle del Vilcanota en Cusco. Penelope Harvey and Teresa Tupayachi trabajaron juntas el tema. El presente artículo investiga cómo se experimentan y entienden las discontinuidades entre diversas instancias del Estado. A partir de un estudio etnográfico del Valle Sagrado, en el departamento de Cusco, el artículo examina las políticas de la materia que implica la gestión de residuos sólidos en tiempos neoliberales. Enfrentados con el problema de cómo manejar los residuos sólidos, los ciudadanos del Cusco y del Valle Sagrado experimentan una falta de responsabilidad institucional y demandan mayor presencia del Estado. El artículo describe los esfuerzos de los expertos técnicos por diseñar sistemas integrales para la gestión de los residuos, sistemas que aprovechan las posibilidades de reciclado para transformar la ‘basura’ (materia tóxica) en materia con vitalidad económica, lo que ahora se conoce como ‘residuos sólidos’. La financiación de los residuos parece llevar a un bien común incontestable. Sin embargo, encontramos que en la práctica los esfuerzos para diseñar un sistema viable para recolectar y tratar a los residuos en un espacio político descentralizante manifiesta profundas tensiones y contradicciones sociales. Las discontinuidades sociales que la descentralización implica perturban las posibilidades y promesas de los infraestructuras integradas. Los actores locales resisten las soluciones que se impone desde arriba y buscan no solo soluciones alternativas, sino también nuevas maneras de formular los problemas de un modo más preciso, y su relación más amplia con el Estado.
This article and the previous «Convergence and divergence between the local and regional state around solid waste management. An unresolved problem in the Sacred Valley» from Teresa Tupayachi are published as complementary accounts on the management of solid waste in the Vilcanota Valley in Cusco. Penelope Harvey and Teresa Tupayachi worked together on this theme. The present article explores how discontinuities across diverse instances of the state are experienced and understood. Drawing from an ethnographic study of the Vilcanota Valley in Cusco, the article looks at the material politics of waste disposal in neoliberal times. Faced with the problem of how to dispose of solid waste, people from Cusco experience a lack of institutional responsibility and call for a stronger state presence. The article describes the efforts by technical experts to design integrated waste management systems that maximise the potential for re-cycling, minimise toxic contamination, and turn ‘rubbish’ into the altogether more economically lively category of ‘solid waste’. However while the financialization of waste might appear to offer an indisputable public good, efforts to instigate a viable waste disposal business in a decentralizing political space elicit deep social tensions and contradictions. The social discontinuities that decentralization supports disrupt ambitions for integrated solutions as local actors resist top-down models and look not just for alternative solutions, but alternative ways of framing the problem of urban waste, and by extension their relationship to the state.

Style APA, Harvard, Vancouver, ISO itp.

4

Carver, S. J. "Application of geographic information systems to siting radioactive waste disposal facilities". Thesis, University of Newcastle Upon Tyne, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.315467.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

5

Smith, Kurt. "Radionuclide behaviour in hyperalkaline systems relevant to geological disposal of radioactive waste". Thesis, University of Manchester, 2014. https://www.research.manchester.ac.uk/portal/en/theses/radionuclide-behaviour-in-hyperalkaline-systems-relevant-to-geological-disposal-of-radioactive-waste(0b04ab1b-4392-4cd3-81d7-c2ba02fd782d).html.

Pełny tekst źródła

Streszczenie:

In many countries the current plan for the management of intermediate and high level radioactive wastes is to dispose of the radioactive materials underground in a Geological Disposal Facility (GDF) to prevent release of radioactivity to the environment. In the UK, the repository for intermediate level waste may be backfilled with cementitious material and it is clear that grout and cement will be used during many disposal concepts. Upon saturation, the cement will react creating a region of hyperalkaline geochemical conditions extending away from the GDF, within which, significant changes in radionuclide behaviour are expected. Therefore, this thesis utilises a range of experimental and analytical techniques to try to gain a mechanistic understanding of the behaviour of some key radionuclides (U(VI), Np(V) and Eu(III) as an analogue for Cm(III)/Am(III)) in a range of high pH systems of direct relevance to any cementitious GDF. U(VI) interaction with calcite (calcium carbonate, a common component in high pH cements and the natural environment) surfaces was studied in the 'old' (Ca(OH)2 solution; pH 10.5) and 'young' (Na+, K+, Ca2+; pH 13.3) leachates. In the 'old' leachate, luminescence spectroscopy, batch experiments and kinetic modelling suggested that at low concentrations (smaller or equal to 0.42 µM) a Ca2UO2(CO3)3-like surface complex formed. At higher concentrations, batch experiments, extended X-ray absorption fine structure spectroscopy and luminescence suggested that a surface mediated precipitation mechanism was controlling U(VI) concentrations. Further TEM analysis confirmed that a calcium uranate (CaUO4) solid phase was forming on the calcite surfaces. In the 'young' leachate, batch experiments showed that U(VI) had little affinity for the calcite surface, with no statistically relevant removal from solution observed over a 18 month period. Small angle X-ray diffraction data demonstrated that the U(VI) was probably present in the form of U(VI) intrinsic colloids. Np(V) solubility and sorption to calcite under hyperalkaline conditions were studied using batch, X-ray absorption spectroscopy, and geochemical modelling techniques. It was determined that Np(V) solubility in 'old' cement leachates was consistent with the literature. However, in 'young' cement leachates, an unidentified calcium containing phase was controlling solubility. It was demonstrated that sorption to calcite in 'old' leachates was controlled by the formation of a >CO3NpO2 surface complex, whereas, in the 'young' leachates interaction with the calcite surface was controlled by a precipitation mechanism. Eu(III) sorption to a potential GDF backfill material, Nirex Reference Vault Backfill (NRVB) cement, was studied. The kinetics of removal were rapid with 98.5% Eu(III) removal within 24 hours. Ultrafiltration experiments indicated that all Eu(III) remaining in solution was associated with NRVB derived colloids. Additional experiments using ethylenediaminetetraacetic acid (EDTA) as a competing ligand show that removal from solution was significantly reduced at high concentrations (>0.01 M). These EDTA experiments also indicated some irreversibility in the systems, possibly caused by incorporation into the C-S-H or calcite structures.

Style APA, Harvard, Vancouver, ISO itp.

6

Smeby, Kristen Lyn. "Occurrence and fate of fluoroquinolone antibiotics in wastewater treatment systems". Thesis, Georgia Institute of Technology, 2002. http://hdl.handle.net/1853/19914.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

7

Salim, Mohd Razman. "Comparative studies of landfill leachate treatment using aerobic, anaerobic and adsorption systems". Thesis, University of Newcastle Upon Tyne, 1992. http://hdl.handle.net/10443/373.

Pełny tekst źródła

Streszczenie:

Landfill leachate with its variable and complex characteristics poses a well established threat to the environment. Enhancement of the environmental quality through the minimization of the leachate problem should therefore be the major objective of good landfill management. The need to control and manage landfill leachate has resulted in various treatment alternatives which include both biological and physical-chemical processes. The research described in this thesis discusses the feasibility of biological and physical-chemical treatment of leachate based on laboratoryscale reactors. After a short introduction, a review of the relevant literature on solid waste disposal including landfilling, leachate generation and the treatment alternatives was presented. Comparative experimental studies were then carried out using an aerobic rotating biological contactor (RBC), an upflow anaerobic filter (UAF) and an activated carbon (AC) adsorption column for treating landfill leachate. The effect of a range of parameters on the performance and operation of the RBC, the UAF and the AC column has been evaluated in the study From the experimental results, an RBC was found to achieve a better performance when treating a low strength (LS) leachate, whereas a high strength (HS) leachate would be much better treated by a UAF. For the LS leachate treatment, a COD removal of 80% at a loading rate of 6 kg COD/m3.d was achieved by the RBC as compared to only 60% by the UAF. Whereas for the HS leachate the RBC achieved a COD removal of only 50% at the loading rate of 14 kg COD/m3.d as compared to 60% by the UAF. Direct physical-chemical treatment process in treating leachate using an AC adsorption was also investigated. The results obtained showed that the adsorption process was not capable of achieving the desired effluent requirement, with 20% residual organic fractions still remaining in the effluent. The need to remove this biodegradable organic matter by biological processes was found to be necessary. It is suggested that to achieve satisfactory treatment, anaerobic UAF treatment of leachate followed by aerobic RBC and a final polishing with AC column should be used.

Style APA, Harvard, Vancouver, ISO itp.

8

Neufeld, Josh D. "Development of a quantitative method for functional gene detection in pulp and paper wastewater treatment systems". Thesis, McGill University, 2000. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=33430.

Pełny tekst źródła

Streszczenie:

The recent development of culture-independent methods has revolutionized the study of complex microbial communities such as those present in activated sludge treatment systems. DNA probes that hybridize to genes coding for key enzymes that catalyze microbial processes have been widely used. Can such probes be used to quantify target genes and thus quantify the potential of a microbial community to carry out a reaction of interest?
Optimal conditions for DNA extraction, probe validation, hybridization, and activity measurements were determined for the pulp and paper treatment system environment under study. Using gene probes for key denitrification genes (nirS, nirK), the correlation between denitrifiers and denitrification activity in an enrichment culture and activated sludge samples was tested. The same correlation between nitrogen fixation and nitrogen-fixing bacteria in primary clarifiers was assessed using a probe for the gene encoding a component of the nitrogenase enzyme (nifH). This work was successful in establishing the correlation between gene numbers and their corresponding enzymatic activity and thus supports the quantitative hybridization approach for the monitoring of microbial communities. (Abstract shortened by UMI.)

Style APA, Harvard, Vancouver, ISO itp.

9

Frigon, Dominic. "Molecular and phenotypic characterization of the microbial communities in two pulp and paper wastewater treatment systems". Thesis, McGill University, 1998. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=29803.

Pełny tekst źródła

Streszczenie:

Phylogenetic hybridization and phenotypic fingerprinting were applied to the analysis of bacterial communities in wastewater treatment systems. These approaches were aimed at (i) developing monitoring tools able to foresee operational problems, and (ii) providing the rationale to optimize the operation of bioreactors. The work presented is intended to first describe the community found in two reactors treating pulp and paper mill effluent, and second evaluate the possibilities of these techniques with respect to the development of new monitoring tools.
Phylogenetic membrane hybridization showed that the bacterial communities were dominated by Alpha and Beta Proteobacteria, a structure probably linked to the low F:M ratio. Other important factors determining the community structure were the proportion of COD in the high molecular weight fraction, the sludge age, phosphate addition, and the concentration of specific compounds (alcohols, phenols, volatile fatty acids) in the influent. The community structure partly determined the sludge characteristics demonstrating its potential value in the assessment of reactor performance. The results obtained by phylogenetic membrane hybridization suggest that the probes used in a monitoring tool would not need to be targeted to the species level to provide relevant information. However, they also suggest that the technique is more sensitive to changes in population density as opposed to changes in bacterial metabolism.
Phenotypic fingerprinting measured a smaller difference between the communities of the two reactors studied than what was measured by phylogenetic membrane hybridization. However, differences in heterotrophic activities observed between the two communities were linked to differences in influent composition.

Style APA, Harvard, Vancouver, ISO itp.

10

Ijzerman, M. Marian. "Evaluation of shallow-placed low pressure distribution systems in soils marginally suited for on-site waste treatment". Thesis, This resource online, 1990. http://scholar.lib.vt.edu/theses/available/etd-03242009-040620/.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

11

Dunn, Kevin Matthew. "The biotechnology of high rate algal ponding systems in the treatment of saline tannery wastewaters". Thesis, Rhodes University, 1998. http://hdl.handle.net/10962/d1004066.

Pełny tekst źródła

Streszczenie:

Salinisation has been identified as a major cause of the progressive deterioration in the public water system in South Africa. To deal with this problem Waste Stabilisation Ponding systems have been used by the Leather Processing Industry as zero-dischaJ;ge wastewater evaporation disposal processes in water-limited inland regions of the country. While effective in the evaporation disposal function these systems are plagued by the generation of serious odour nuisance creating intractable environmental problems relating to adjacent residential communities. High loading to ponds of organic compounds, sulphides and ammonia results in strongly reducing anaerobic conditions prevailing in early parts of pond cascades. These are characterised by bright red colours due to the predominance of purple photosynthetic bacteria. Sporadic micro algal blooms of Spirulina sp. and Dunaliella sp. had been previously noted to occur on the latter ponds in these cascades, and were associated with their conversion to facultative function, with aerobic surface layers, and a marked reduction in odour release. This research programme undertook an investigation of the microbial ecology of a tannery waste stabilisation ponding system to describe factors which give rise to these blooms, and to determine whether microalgal growth may be manipulated to achieve a reliable oxygengenerating capping of the anaerobic ponds. The predominance of near pure cultures of Spin/lina platensis was demonstrated for the blooms and factors restricting its growth in the system were described. These include the interaction of ammonia and sulphide toxic effects and laboratory studies were undertaken to show how effluent loading may be regulated to enable effective growth of the cyanobacterium. At appropriate dilutions of tannery effluent an enhancement of growth was noted, compared to growth in defined mineral medium. An investigation of this phenomenon provided preliminary evidence for organic uptake by the pond micro algae and a possible contribution to heterotrophic nutrition. The manipulation of Spirulina sp. growth in a High Rate Algal Pond raceway was undertaken in outdoor pilot plant studies and the effect of microalgal capping of the anaerobic ponds in the cascade was demonstrated by activating a recycle loop from a blooming facultative pond. Heavy metal contaminants were effectively eliminated by an optimisation of the primary anaerobic pond function and precipitation as metal sulphides. Biomass was harvested and dried, during which a range of methods were evaluated. Toxicological studies were undertaken on the dried biomass using Artemia and chick assays, and feed studies showed its useful application in rations for the abalone Haliotlls midae and rainbow trout Onchorhynchlls mykiss. Based on positive independent assessment of research outcomes, a decision was made by the tanning company operating the Waste Stabilisation Ponding system, to proceed to the construction of a full-scale 2 500 m2 High Rate Algal Pond raceway. This would be used for controlled Spirlilina biomass production to effect a practical capping of the anaerobic ponds in the system, and to evaluate its commercial potential in the feed market. The Advanced Integrated Wastewater Ponding System described by Oswald (1991) provided the conceptual basis for the Algal Biotechnology process development undertaken. The studies of the microbial ecology and the biotechnological potential of this system have shown that a Spirulina-based High Rate Algal Ponding process can be engineered in such a way that saline tannery effluents may be treated to effect a significant reduction in overall pollution load, that biomass may be recovered as a value added product of the treatment process and that the operational performance of Waste Stabilisation Ponding systems, and hence their immediate environment, may be improved by the use of the High Rate Algal Pond as a retrofitted upgrading unit operation.

Style APA, Harvard, Vancouver, ISO itp.

12

Bamber, Andrew Sherliker. "Integrated mining, pre-concentration and waste disposal systems for the increased sustainability of hard rock metal mining". Thesis, University of British Columbia, 2008. http://hdl.handle.net/2429/779.

Pełny tekst źródła

Streszczenie:

The integration of automated ore pre-concentration and waste disposal functions into the hard rock metal mining system, prior to treatment by conventional grinding and flotation, is proposed as a novel interpretation of Mine-Mill Integration for improving the economics and environmental impact of exploiting deep, low-grade or otherwise marginal mineral deposits. The proposed approach seeks to reject coarse, barren waste from the ore stream as early as possible in the mining cycle, and safely dispose of it as backfill underground. The concept is proposed as a Lean Manufacturing approach to hard rock mining, as an alternative to improving the economics of mining simply by increasing the mining rate. Lean Manufacturing philosophy seeks to design out overburden, smooth production, and eliminate waste from the system. It is suggested that the introduction of these systems into the hard rock mining process addresses all three of these areas of Lean thinking, and is thus an important approach to be considered for surface or underground mines wishing to simultaneously improve efficiency, economics and environmental performance, thus increasing the life, and the sustainability of the operation. The application of integrated mining, processing and waste disposal systems, where appropriate, is proposed as a strategy for the development of efficient new mining operations, or alternately the expansion of production at existing mines. Technologies specific to the success of the approach such as automated ore pre-concentration systems, composite fill preparation and delivery systems, as well as continuous mechanized mining methods are explored. The impacts and benefits of applying these integrated technologies to the mining system are defined and quantified through research, testwork, engineering design and systems analysis. Custom geo-metallurgical evaluation tools incorporating mineralogical, metallurgical, geophysical and geotechnical methods have been developed to allow the assessment of ores in terms of their potential for the adoption of the proposed approach. A computerized parametric evaluation model has also been developed to quantify the potential impacts and benefits using data from this testwork. A wide range of case studies have been investigated with positive results, and important conclusions are drawn towards the potential for application of the concept as a generalized case.

Style APA, Harvard, Vancouver, ISO itp.

13

Min, Bryan B. "Selection of disposal method for nuclear spent fuel : a plan for the application of the systems engineering process /". Master's thesis, This resource online, 1996. http://scholar.lib.vt.edu/theses/available/etd-02162010-020330/.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

14

Elshayeb, Monalisa. "Determining food web impacts on experimental aquatic systems from the disposal of oil sands process-affected waste materials". Thesis, University of Waterloo, 2006. http://hdl.handle.net/10012/2973.

Pełny tekst źródła

Streszczenie:

Current mining operators in the Athabasca oil sands deposit of Alberta, Canada have made commitments to zero discharge of oil sands process-affected waste materials (OSPM) from the mine site and rehabilitation of mined lands to a pre-mining state. As part of aquatic reclamation efforts, experimental test sites that contain a range of OSPM (solid and liquid components) were constructed to monitor the evolution and viability of aquatic habitats used as disposal sinks for OSPM produced by mining activities. In the present study, stable isotopes of carbon, nitrogen and sulphur were used to gauge some of the potential effects of OSPM site construction methods on aquatic food webs. Carbon and nitrogen isotopic signatures of sediment, dissolved inorganic carbon, dissolved organic carbon, particulate organic matter, periphytic material, plants, plankton, aquatic invertebrates and fish were used to assess differences related to the naphthenic acid (NA) concentration in OSPM and reference sites. For statistical analyses, sites were grouped into low (0 to 4 mg/L), medium (4 to 15 mg/L) and high (> 15 mg/L) NA concentrations. There were no significant differences in food web area or food web length among the low, medium and high NA concentration sites. In most cases, sample carbon isotope analyses of low, medium and high NA concentration sites were not significantly different, suggesting food web carbon sources did not include significant contributions from OSPM materials at OSPM sites. Significant differences, however, were found in the sample nitrogen isotope signatures between low, medium and high NA concentration sites. Ammonia from OSPM is suggested to be the main contributor to δ¹⁵N enrichment.

To determine the potential effects of site construction and OSPM within experimental test sites, carbon and sulphur stable isotopes of water, plankton, aquatic invertebrates and fish were analyzed. With the exception of Chaoborus and Haliplus, all carbon isotope signatures were not significantly different in constructed and reference sites. Also with the exception of Haliplus, sulphur isotope values for aquatic organisms from constructed and reference sites were significantly different. Aquatic organisms and water samples from constructed sites built in, or close, to the boundary of Kcw clays typically had δ³⁴S < 0 ?. Coinciding with depleted δ³⁴S signatures found in these aquatic systems were elevated sulphate concentrations. The waters at experimental test sites are in direct contact with the soil materials that facilitate the accumulation of sulphates as a result of the oxidation of substrate sulphide minerals. In general the results of the study suggest that aquatic food web structure and function do not change with the introduction of OSPM. Shifts in isotopic signatures suggestive of changes in food web structure, however, do occur when site construction exposes Kcw clays in the substrate.

Style APA, Harvard, Vancouver, ISO itp.

15

Zeng, Yinghui. "Internet-based fuzzy logic and statistics models for integrated solid waste management planning /". free to MU campus, to others for purchase, 2004. http://wwwlib.umi.com/cr/mo/fullcit?p3164557.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

16

Dekker, Leendert Gideon. "Development of integrated algal ponding systems in the treatment of wine distillery wastewaters". Thesis, Rhodes University, 2003. http://hdl.handle.net/10962/d1004530.

Pełny tekst źródła

Streszczenie:

In South Africa, wastewater disposal in the wine and distilling industry is undergoing a profound transformation as a result of fundamental changes in regulations and license requirements. To deal with this problem conventional Waste Stabilisation Ponding systems have been used by the industry together with irrigation and evaporation disposal practises. Although effective in the evaporation and containment disposal functions, these pond systems are generally not properly designed and/or managed, resulting in overloading and, at times, the generation of seriously offensive odour problems. Preliminary studies on the feasibility of utilising the Advanced Integrated Wastewater Ponding System as a core treatment technology in winery wastewater treatment were conducted. Results indicated that specific problems had to be addressed before successful ponding treatment could be achieved. This research programme undertook an investigation of the performance of a demonstration ponding system treating household sewage, which formed the basis of the research due to limited experience reported on ponds treating wine industry wastewaters. Malfunctions identified were in correlation with the preliminary winery waste ponding survey, which included unstable fermentation pit functions and inadequate nutrient removal. Retrofitting the fermentation pit with a nylon net across the rising water column resulted in improved retention of active anaerobic sludge, especially during periods of system start-up and/or organic overloading. An investigation into nutrient removal utilising algal biomass provided a valuable contribution towards development of an independent nutrient removal system. Harvested algal biomass was passively manipulated to release polysaccharides under anoxic conditions, with subsequent use as a carbon source by denitrifying organisms. Following denitrification, the still viable algal cells were introduced into a High Rate Algal Pond raceway for photosynthetically produced alkalinity. This high pH environment resulted in induced calcium phosphate mineral formation and subsequent precipitation, as well as effective ammonia stripping from the water. Based on the novel positive research outcomes a decision was made to proceed to the construction of a pilot-scale integrated ponding system treating wastewater from a wine lees factory. The system linked the Anaerobic Baffle Reactor, for pre-treatment, with the improved Advanced Integrated Wastewater Ponding System. The potential of this system has shown that a Waste Stabilisation Ponding system can be engineered to treat wine industry wastewaters and thereby effectively reduce the organic and nutrient loads, by using low-cost retrofitted upgrading unit operations. Valuable algal biomass may also be recovered as a by-product of the treatment process.

Style APA, Harvard, Vancouver, ISO itp.

17

Gauthier, Francis. "Study of coliform bacteria in Canadian pulp and paper mill water systems : their ecology and utility as health hazard indicators". Thesis, McGill University, 2000. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=33401.

Pełny tekst źródła

Streszczenie:

Coliform bacteria have long been used to indicate fecal contamination of food, water, and solid surfaces, and thus the presence of a health hazard. In this study, the in-mill water and external effluent treatment systems of seven typical Canadian pulp and paper mills were shown to support the growth of numerous coliforms, especially Klebsiella spp, Escherichia coli, Enterobacter spp., and Citrobacter spp . Mill coliforms were shown to be not just simple transients from feedwater or furnish (wood), but to be continuously growing, especially in the primary clarifiers. Therefore, coliforms and fecal coliforms cannot be used as fecal contamination indicators in pulp and paper mill water and effluent treatment systems.
N2-fixing coliform populations were detected in mill water systems and were analyzed using N2-fixation assays and nitrogenase gene (nifH) probing. Both active in situ populations and cultured microbial isolates were tested. Active N2-fixation was demonstrated in six primary clarifiers. Measurement of the numbers and composition of the total culturable bacterial community in a primary clarifier revealed that approximately 50% of all aerobic cells contained nifH , of which >90% were Klebsiella. Coliforms growing on MacConkey agar plates from the primary clarifier were all identified as Klebsiella and 100% of these Klebsiella contained the nifH gene. Preliminary estimates indicate that the amount of N2 fixed per day is substantial in some clarifiers.

Style APA, Harvard, Vancouver, ISO itp.

18

Cardoso, Antonio J. "Relationship of waste characteristics to the formation of mineral deposits in leachate collection systems". [Tampa, Fla.] : University of South Florida, 2005. http://purl.fcla.edu/fcla/etd/SFE0001266.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

19

Melamane, Xolisa Lorraine. "Treatment of wine distillery wastewaters by high rate anaerobic digestion and submerged membrane systems". Thesis, Rhodes University, 2007. http://hdl.handle.net/10962/d1004022.

Pełny tekst źródła

Streszczenie:

Experiences in treating wine distillery wastewaters (WDWs) contribute to the field of oenology as many oenologists are concerned with the selection, efficiency and economy of their wastewaters. Wine distillery wastewaters are strongly acidic, have high chemical oxygen demand (COD), high polyphenol content and are highly variable. Primary attention was focussed on sustainable biological treatment of raw wine distillery wastewater (RWDW) and fungally pre-treated wine distillery wastewater (FTWDW) by energy-efficient high rate anaerobic digestion (AD). This study also explored the development of a novel dual-stage anaerobic digestion ultrafiltration (ADUF) process, using a ceramic submerged membrane bioreactor (SMBR) in the treatment of both RWDW and FTWDW. The first stage was for the selection of microorganisms that were able to treat the toxic pollutants from WDWs. It was operated at a high feed-to-microorganism ratio. The second stage, a secondary digester, was operated like a typical membrane bioreactor at a low feed-to-microorganism ratio to sustain a stable efficient population for a long period. The characteristics of RWDW were as follows: pH 3.83, 15 000 mg/l soluble COD (CODs) and 5229 mg/l of phenols. After pre-treatment of RWDW with Trametes pubescens, starting parameters for FTWDW were as follows: pH 6.7, 7000 mg/l soluble COD (CODS) and 1440 mg/l of phenols. During operation of a high rate anaerobic digester for RWDW treatment, K2HPO4 was required for buffering the digester. Volatile fatty acid concentrations were <300 mg/l throughout the study, indicating degradation of organic acids present. Mean CODS removal efficiency for the 130 day study was 87 %, while the mean polyphenol removal efficiency was 85 %. Addition of 50 mg/l Fe3+ increased the removal efficiencies of CODS to 97 % and of polyphenols to 99 %. High removal efficiencies of CODS and polyphenols were attributed to the addition of macronutrients and micronutrients that caused pH stability and stimulated microbial activity. The CODS removal efficiency of high rate anaerobic digestion of FTWDW reached 99.5%. During FTWDW digestion, pH buffering was achieved using K2HPO4. A combination of a SMBR and a secondary digester was tested for the treatment of RWDW and FTWDW during a 30 day study. Results for RWDW showed that pH buffering was achieved by dosing the feed stream with CaCO3 and K2HPO4. Buffering proved to be significant for optimum performance of the system in removal of soluble CODS, and volatile fatty acids (VFAs). Different batches of RWDW used for feeding the reactor had variable compositions with respect to concentrations of nitrates, ammonium and total phenolic compounds. Ammonium accumulated in the secondary digester after 14 days of system operation, indicated the time required for the establishment of anaerobic conditions in the system. Dosing of the SMBR treating FTWDW with CaCO3 and K2HPO4 buffered the pH; iii this proved significant for optimum performance of the system in removal of CODS. The system eliminated an average of 86 (± 4) % of CODS present in the FTWDW. The residual CODS levels in the effluent were approximately 400 mg/l, significantly lower than the concentrations observed when treating RWDW, indicating that fungal pre-treatment might have provided additional nutrients for removal of recalcitrant components of the wastewater. The resulting effluent was rich in nitrates and phosphates and might be used as a fertiliser. Alternatively, a membrane process, such as reverse osmosis (RO) or nanofiltration (NF) could be applied to raise the water quality to meet the levels required for reuse. Biomass samples were obtained from the four treatment systems and population shifts characterization using phospholipids fatty acids (PLFA) and 16S rRNA analysis to provide an indication of limitations within the microbial population. The values of the concentrations of the individual PLFAs detected in the samples indicated that ten bacterial species were present, with the GC content of the 16S rRNA increasing from 1 to 10. Analysis of denaturing gradient gel electrophoresis DGGE data indicated that the composition of the archeal community changed the consortia used for both RWDW and FTWDW treatment. Changes in band intensities indicated the presence of different components of the archeal communities. The results were not conclusive in terms of species identity as cloning, sequencing and phylogenetic analyses were not performed, but they did indicate microbial population shifts and species diversity for high rate anaerobic digestion. The results also confirmed prevalence of relatively few species during operation of SMBRs for treatment of RWDW and FTWDW, which suggested that the microorganisms that survived were either tolerant of toxic components of RWDW and FTWDW or they were able to remove polyphenols.

Style APA, Harvard, Vancouver, ISO itp.

20

Callahan, Thomas Patrick. "Non-Newtonian fluid injection into granular media". Thesis, Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/39618.

Pełny tekst źródła

Streszczenie:

The process of fluid injection into granular media is relevant to a wide number of applications such as enhanced oil recovery, grouting, and the construction of permeable reactive barriers. The response of the subsurface is dependent on multiple factors such as in-situ stresses, fluid properties, flow rate, and formation type. Based on these conditions a variety of response mechanisms can be initiated ranging from simple porous infiltration to hydraulic fracturing. Currently, the mechanics of fluid injection into competent rock are well understood and can be sufficiently modeled using linear elastic fracture mechanics. Because the grains in rock formations are individually cemented together, they exhibit cohesion and are able to support tensile stresses. The linear elastic method assumes tensile failure due to stress concentrations at the fracture tip. A fracture propagates when the stress intensity factor exceeds the material toughness (Detournay, 1988) However, understanding fluid injection in cohesionless granular media presents a much larger obstacle. Currently, no theoretical models have been developed to deal with granular media displacements due to fluid injection. Difficulty arises from the complexity of fluid rheology and composition used in engineering processes, the strong coupling between fluid flow and mechanical deformation, the non-linear response of subsurface media, and the multi-scale nature of the problem. The structure of this thesis is intended to first give the reader a basic background of some of the fundamental concepts for non-Newtonian fluid flow in granular media. Fluid properties as well as some interaction mechanisms are described in relation to the injection process. Next, the results from an experimental series of injection tests are presented with a discussion of the failure/flow processes taking place. We developed a novel technique which allows us to visualize the injection process by use of a transparent Hele-Shaw cell. Specifically, we will be using polyacrylamide solutions at a variety of concentrations to study non-Newtonian effects on the response within the Hele-Shaw cell. By performing tests at a range of solution concentrations and injection rates we are to be able to identify a transition from an infiltration dominated flow regime to a fracturing dominated regime.

Style APA, Harvard, Vancouver, ISO itp.

21

Pas, Joshua W. "Contract and strategic network design for reverse production systems". Diss., Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/22577.

Pełny tekst źródła

Streszczenie:

Thesis (Ph. D.)--Industrial and Systems Engineering, Georgia Institute of Technology, 2008.
Committee Co-Chair: Ammons, Jane C.; Committee Co-Chair: Realff, Matthew J.; Committee Member: Griffin, Paul M.; Committee Member: Peoples, Robert; Committee Member: Thomas, Valerie.

Style APA, Harvard, Vancouver, ISO itp.

22

John, David E. "Transport and Survival of Water Quality Indicator Microorganisms in the Ground Water Environment of Florida: Implications for Aquifer Storage and Waste Disposal". [Tampa, Fla.] : University of South Florida, 2003. http://purl.fcla.edu/fcla/etd/SFE0000155.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

23

Fortin, Nathalie. "Molecular characterization of dechlorination potential in kraft pulp mill effluent treatment systems". Thesis, McGill University, 1996. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=27317.

Pełny tekst źródła

Streszczenie:

Many low molecular weight chlorinated organic compounds produced by the pulp and paper industry during kraft bleaching of the wood pulp are toxic. Mass balance studies suggest that mineralization of chlorinated organics is occurring in pulp and paper mill wastewater treatment systems. To understand the nature of dechlorination activity, molecular tools such as oligonucleotide primers and corresponding DNA probes were developed to monitor the presence of microorganisms possessing key genes (dehalogenases) responsible for the degradation of chloroaliphatic organics in kraft pulp mill effluent treatment systems. Oligonucleotide primers designed from the coding sequence of known dehalogenases and a methane monooxygenase gene, which is known to catalyze dehalogenation reactions, were used for polymerase chain reaction (PCR) analysis, using genomic DNA extracted from dehalogenating bacterial isolates and total community DNA extracted from water and sediments of lagoon treatment systems. PCR amplification with dhlB oligonucleotide primers, designed from the haloacid dehalogenase of Xanthobacter autotrophicus, revealed the presence of dehalogenase genes in both aerated lagoons and stabilization basins. Similar results were obtained with mmoX primers designed from the methane monooxygenase gene of Methylococcus capsulatus. DNA sequence analysis of several PCR fragments showed significant similarity to known dehalogenase genes. The molecular tools developed in this study revealed the presence of different types of microorganisms with dechlorination potential in the microbial community of pulp mill effluents.

Style APA, Harvard, Vancouver, ISO itp.

24

Karius, Ralf. "Developing an integrated concept for sewage sludge treatment and disposal from municipal wastewater treatment systems in (peri-)urban areas in Vietnam". Master's thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2011. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-71141.

Pełny tekst źródła

Streszczenie:

The study took place in Vietnam at Hanoi University of Science in the framework of the DAAD (German Academic Exchange Service) – “An advancement of the German-Vietnamese University partnerships”. The research has been supported by the program: “Wastewater and Solid Waste Management in Provincial Centers” and belongs to its technical component. The present diploma thesis elaborates the current situation of sewage sludge management in Vietnam and is dealing with sludge characteristics from both domestic sewage treatment facilities and septic tanks. During the research, different treatment components and treatment facilities have been analyzed to carry out a comprehensive survey of sewage sludge types. In this thesis, a guideline (draft) was developed as a main result, which can be helpful to bridge the legislative gap for sewage sludge re-use in Vietnam. In conclusion, an integrated concept has been developed, which recommends the application of selected proceeding elements to treat sewage sludge and the further utilization of re-useable materials in agriculture in a controlled and environmentally-safe manner
Die Diplomarbeit wurde im Rahmen des Deutsch-Vietnamesischem Auslandsaustauschprogramms an der „Hanoi University of Science“ verfasst. Dieses Vorhaben wurde unterstützt von dem DAAD (Deutschen Akademischen Austausch Dienst), und ist im technischem Bereich des Programms “Wastewater and Solid Waste Management in Provincial Centers“ einzugliedern. Die vorstehende Diplomarbeit beschäftigt sich mit dem aktuellen Klärschlammmanagement in Vietnam und liefert dabei detaillierte Resultate zu verschiedenen Klarschlammtypen aus kommunalen Abwasserbehandlungsanlagen. Bei den Untersuchungen wurden verschiedene Abwasser- und Klärschlammbehandlungsanlagen untersucht, um einen Überblick zu den gebräuchlichen Behandlungsmethoden in Vietnam zu erarbeiten. Zusätzlich wurden die institutionellen und rechtlichen Rahmenbedingungen überprüft. Der Entwurf einer Verordnung zur Verwertung von Klärschlamm in der Landwirtschaft wurde vorgelegt, um eine bestehende rechtliche Lücke in Vietnam zu schließen. Mit dieser Arbeit wurde ein integriertes Konzept entwickelt, welches mittels verschiedene verfahrenstechnische Elemente den Klärschlamm behandelt und darauffolgend das verwertbare Material in ausgewählten landwirtschaftlichen Flächen in einer kontrollierten und umweltschonenden Weise verwertet

Style APA, Harvard, Vancouver, ISO itp.

25

Silva, Fábio. "Sistema de gestão integrada de dados para repositórios de rejeitos radioativos (SGI3R)". CNEN - Centro de Desenvolvimento da Tecnologia Nuclear, Belo Horizonte, 2010. http://www.bdtd.cdtn.br//tde_busca/arquivo.php?codArquivo=134.

Pełny tekst źródła

Streszczenie:

Nenhuma
A implantação de um repositório para rejeitos radioativos é um projeto multidisciplinar que demanda além de especialistas de diferentes áreas do conhecimento, a interação com instituições públicas e privadas, dados e informações relacionadas com rejeitos radioativos, geologia, tecnologia etc. Todas as atividades devem estar em conformidade com as normas, requisitos e procedimentos, incluindo a legislação nacional e internacional. A manutenção dos registros de inventário dos rejeitos é um requisito importante regulamentar e deverá estar disponível até mesmo após o encerramento do repositório. O Centro de Desenvolvimento da Tecnologia Nuclear CDTN está coordenando o projeto para a construção do repositório nacional para o armazenamento dos rejeitos de baixo e médio nível de radiação. A fim de consolidar todas as informações que serão provenientes deste projeto, está sendo desenvolvido e implantado no CDTN um sistema Gerenciador de banco de dados, chamado de Sistema de Gestão Integrada de dados para Repositórios de Rejeitos Radioativos (SGI3R), que também vai gerenciar todos os dados de trabalhos anteriores realizados no Brasil e em todo o mundo sobre este assunto. A proposta é criar uma estrutura de módulos, tendo como base oito módulos: inventário, seleção de sites, tipos de repositório, tecnologia, parceiros, legislação, comunicação e documentos. O SGI3R compreende a integração (inclusão, atualização e exclusão), processamento de dados, padronização e consistência entre os processos. O SGI3R dará apoio às etapas deste projeto, que permitirá a preservação de todas as informações disponíveis, evitando a duplicação de esforços e custos adicionais, melhorando, deste modo, o projeto de planejamento e execução. Adicionalmente o SGI3R permitirá o acesso às informações para todas as partes interessadas.
The implantation of a repository for radioactive wastes is a multidisciplinary project that demands in addition to specialists of different areas of knowledge, interaction with public and private institutions, data and information related to radioactive wastes, geology, technology etc. All the activities must be in accordance with norms, requirements and procedures, including national and international legislation. The maintenance of the waste inventory records is an important regulatory requirement and must be available even after the closure of the repository. The Center of Nuclear Technology Development CDTN is coordinating the Project for the construction of the national repository to store the low and intermediatelevel wastes. In order to consolidate all information that will come from this Project, it is being developed and implanted in CDTN a manager system of database, called Integrated Management System of data for Radioactive Waste Repositories (SGI3R), which will also manage all data from previous works carried out in Brazil and around the world about this subject. The proposal is to build a structure of eight modules: Inventory, Site Selection, Types of Repository, Documents, Technology, Partners, Legislation, and Communication, having initially as base the first four ones. The SGI3R comprises the data processing (inclusion, update and exclusion), integration, standardization, and consistency among the processes. The SGI3R will give support to the stages of this Project, which will allow the preservation of all the available information, preventing duplication of efforts and additional costs, improving, in this way, the Project planning and execution. Additionally the SGI3R will make possible the information access to all stakeholders.

Style APA, Harvard, Vancouver, ISO itp.

26

John, David E. (David Eric). "Transport and survival of water quality indicator microorganisms in the ground water environment of Florida [electronic resource] : implications for aquifer storage and waste disposal / by David E. John". University of South Florida, 2003. http://purl.fcla.edu/fcla/etd/SFE0000155.

Pełny tekst źródła

Streszczenie:

Title from PDF of title page.
Document formatted into pages; contains 322 pages.
Thesis (Ph.D.)--University of South Florida, 2003.
Includes bibliographical references.
Text (Electronic thesis) in PDF format.
ABSTRACT: Ground water resources are heavily used for drinking water supply and often as a receptacle for waste water. One concern is the possible contamination of wetland areas by ground water receiving septic system infiltration. To investigate this, two tracer studies were performed using the bacteriophage PRD-1 by seeding septic systems adjacent to wetlands with the phage and monitoring migration towards wetland areas. Transport velocities were evaluated based on appearance of tracer in sampling wells at various distances from the injection point. Velocities were estimated to be 0.25 m/d and 0.4 m/d at the two sites. Some retardation with respect to the conservative tracer SF6 was observed, with a factor of about 1.5. Due to dry conditions, the water table was well below surface, so transport of the virus into surface water was not observed. Survival of public-health-related microorganisms in ground water is also a concern.
ABSTRACT: The effects of temperature and total dissolved solids (TDS) on survival of 5 groups of indicator organisms were evaluated in controlled experiments. TDS did not have significant effects on inactivation of these microbes up to 1000 mg/l, but there was indication of reduced inactivation of enterococci at TDS concentrations of 3000 mg/l. Increased temperature consistently resulted in more rapid inactivation. Survival in aquifer and reservoir water samples was also evaluated, and significant effects due to water type, temperature, and pasteurization treatment were observed. Inactivation was more rapid in surface water sources, and pasteurization enhanced survival. For enterococci and DNA coliphage, pasteurization effects were more pronounced in surface water. DNA coliphage and perhaps fecal coliform appeared to be the more-conservative indicator organisms for aquifer injection monitoring.
ABSTRACT: Lastly, it was observed that inactivation rates were considerably slower in pore water of saturated limestone than in the bulk water column of similar water sources and conditions, particularly for enterococci and fecal coliform.
System requirements: World Wide Web browser and PDF reader.
Mode of access: World Wide Web.

Style APA, Harvard, Vancouver, ISO itp.

27

García, García Sandra. "Generation, stability and migration of montmorillonite colloids in aqueous systems". Doctoral thesis, KTH, Kemiteknik, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-11847.

Pełny tekst źródła

Streszczenie:

In Sweden the encapsulated nuclear waste will be surrounded by compacted bentonite in the granitic host rock. In contact with water-bearing fractures the bentonite barrier may release montmorillonite colloids that may be further transported in groundwater. If large amounts of material are eroded from the barrier, the buffer functionality can be compromised. Furthermore, in the scenario of a leaking canister, strongly sorbing radionuclides, can be transported by montmorillonite colloids towards the biosphere. This thesis addresses the effects of groundwater chemistry on the generation, stability, sorption and transport of montmorillonite colloids in water bearing rock fractures. To be able to predict quantities of montmorillonite colloids released from the bentonite barrier in contact with groundwater of varying salinity, generation and sedimentation test were performed. The aim is first to gain understanding on the processes involved in colloid generation from the bentonite barrier. Secondly it is to test if concentration gradients of montmorillonite colloids outside the barrier determined by simple sedimentation experiments are comparable to generation tests. Identical final concentrations and colloid size distributions were achieved in both types of tests. Colloid stability is strongly correlated to the groundwater chemistry. The impact of pH, ionic strength and temperature was studied. Aggregation kinetics experiments revealed that for colloid aggregation rate increased with increasing ionic strength. The aggregation rate decreased with increasing pH. The temperature effect on montmorillonite colloid stability is pH-dependent. At pH≤4, the rate constant for colloid aggregation increased with increasing temperature, regardless of ionic strength. At pH≥10, the aggregation rate constant decreased with increasing temperature. In the intermediate pH interval, the aggregation rate constant decreased with increasing temperature except at the highest ionic strength, where it increased. The relationship between the rate constant and the ionic strength allowed the critical coagulation concentration (CCC) for Na- and Ca-montmorillonite to be determined. In order to distinguish the contribution of physical filtration and sorption to colloid retention in transport, the different retention mechanisms were quantified. Sorption on different representative minerals in granite fractures was measured for latex colloids (50, 100, 200 nm) and montmorillonite colloids as a function of ionic strength and pH. Despite of the negative charge in mineral surfaces and colloids, sorption was detected. The sorption is correlated to the mineral point of zero charge and the zeta potential of the colloids, and increases with increasing ionic strength and decreasing pH. In transport experiments with latex colloids in columns packed with fracture filling material, the retention by sorption could clearly be seen. In particular at low flow rates, when the contact time for colloids with the mineral surfaces were the longest, sorption contributed to retention of the transport significantly. The retention of latex colloids appeared to be irreversible in contrary to the reversible montmorillonite colloid retention. Generation, stability and sorption of the montmorillonite colloids are controlled by electrostatic forces; hence, the results were in qualitative agreement with DLVO.

Style APA, Harvard, Vancouver, ISO itp.

28

Alarcon, Leon Edgardo. "Pyrite weathering and lithium (Li?) transport under unsaturated flow conditions in model and mine-tailing systems". University of Western Australia. School of Earth and Geographical Sciences, 2005. http://theses.library.uwa.edu.au/adt-WU2006.0011.

Pełny tekst źródła

Streszczenie:

[Truncated abstract] As mineral deposits continue to be mined, the non economic gangue materials such as sulphides (e.g. pyrite) that are extracted as part of the ore body or overburden are deposited within the waste rock and/or milled tailings. As a result of natural weathering processes, these reactive materials represent a potential hazard to surrounding environments. A major consequence, resulting from mine-waste impoundments containing sulphidic materials, relates to the offsite movement of low pH leachates containing elevated concentrations of metal ions posing a contamination threat. The processes and mechanisms acting in the formation of acid mine drainage (AMD) are highly variable and, to a high extent, controlled by climatic conditions as the main driver of water flow and wetness of the system which in turn determines the availability of oxygen as well as water for pyrite weathering. In particular, this thesis is based on the hypothesis that in semiarid and arid climates the acid production may be water … The experiments were repeated at different water contents ranging from 0.24 to 0.33 cm3 cm-3. Breakthrough curves (BTC) of Li+, K+, Ca2+, Mg2+, Na+ and pH were measured and described with models of different complexities. This included the use of a simple linear and non-linear isotherms for Li+ alone, a binary Li+ - K+ ion exchange, and a complete multicomponent chemical equilibrium description of ion transport. The latter, by including dissolution of primary minerals which released base cations such as Mg2+, Ca2+ and K+ explained some of the elution patterns of base cations for which the Li+ - K+ exchange was the dominant process. Furthermore, under unsaturated water flow conditions, retardation of Li+ increased with decreasing water content. Thus solute mobility in mafic rock tailings appears to decrease under strongly unsaturated water flow conditions.

Style APA, Harvard, Vancouver, ISO itp.

29

LIMA, JOSENILSON B. DE. "Desenvolvimento de uma metodologia para a caracterização de tambores de rejeitos radioativos". reponame:Repositório Institucional do IPEN, 2016. http://repositorio.ipen.br:8080/xmlui/handle/123456789/27131.

Pełny tekst źródła

Streszczenie:

Submitted by Maria Eneide de Souza Araujo (mearaujo@ipen.br) on 2017-03-10T15:06:09Z No. of bitstreams: 1 23000.pdf: 2483857 bytes, checksum: ba54fa302ba8e46dabc056e73e8bd8ee (MD5)
Made available in DSpace on 2017-03-10T15:06:09Z (GMT). No. of bitstreams: 1 23000.pdf: 2483857 bytes, checksum: ba54fa302ba8e46dabc056e73e8bd8ee (MD5)
Rejeitos radioativos são gerados em todas as etapas do ciclo do combustível nuclear e em instituições que fazem uso de elementos radioativos. No Brasil, para que possam atender a legislação vigente, eles devem ser devidamente gerenciados e tratados. A caracterização é a etapa do gerenciamento de rejeitos radioativos que certifica e complementa as informações presentes no documento de identificação fornecido pelo gerador dos rejeitos radioativos. O objetivo desse trabalho foi desenvolver uma metodologia para caracterização de tambores de rejeitos radioativos. Neste trabalho foi utilizada a técnica de espectrometria gama associada ao método de Monte Carlo para obter e estabelecer uma relação entre as eficiências de contagens teóricas e experimentais para quatro tambores de calibração com densidades diferentes, preparados com nove tubos de PVC em seu interior. O detector de HPGe utilizado foi posicionado em três diferentes distâncias em relação a extremidade do tambor de calibração. A utilização do método de Monte Carlo mostrou-se adequado a metodologia proposta neste trabalho.
Dissertação (Mestrado em Tecnologia Nuclear)
IPEN/D
Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP

Style APA, Harvard, Vancouver, ISO itp.

30

Biju, Bárbara Pavani. "Utilização do sistema de informação geográfica (SIG) na indicação de possíveis áreas aptas à disposição de resíduos de construção e de demolição". Universidade Tecnológica Federal do Paraná, 2015. http://repositorio.utfpr.edu.br/jspui/handle/1/1328.

Pełny tekst źródła

Streszczenie:

CAPES
Os resíduos oriundos da construção e demolição quando não têm uma destinação final adequada acarretam em problemas de ordem social, econômica e ambiental. O descarte que muitas vezes acontece em locais inapropriados, demonstra a necessidade de áreas para a correta disposição final em acordo com as normas vigentes. Visando a diminuição dos impactos causados por esse tipo de resíduos, buscando atender a legislação pertinente, a indicação de áreas aptas à implantação de aterros de resíduos de construção e demolição ou aterro classe A faz-se necessária. Para isso, foi utilizada a ferramenta de Sistema de Informação Geográfica (SIG), apoiada pela análise e decisão por multicritérios. O SIG utilizado como ferramenta base na identificação de possíveis áreas adequadas tem como vantagem: o baixo custo; maior rapidez no processo de tomada de decisão e a diversidade de cenários que podem ser analisados ao mesmo tempo, sendo de grande valia nas etapas de gerenciamento dos resíduos de construção e demolição. Integrando o SIG com a ferramenta de análise e tomada de decisão por multicritérios, tem-se como resultado a indicação de possíveis áreas aptas à implantação de aterros de construção civil e inertes para o Núcleo Central Urbano da Região Metropolitana de Curitiba.
The construction and demolition (C&D) waste when do not have a proper final disposal; result in social, economic and environmental problems. The disposal often happens in inappropriate locations and demonstrates the necessity of adequate areas for the waste final disposal but also the selected site must be in accordance with local standards and regulations. Considering all these facts, the aim of this work is to indicate possible suitable areas for C&D waste landfill, using the Geographic Information System (GIS) tool, supported by Multi-criteria Decision Analysis (MCDA). The GIS used as a basic tool to identify possible suitable areas has several advantages: low cost; faster decision-making process and various scenarios can be analyzed simultaneously, being a valuable tool in all the construction and demolition waste management steps. Integrating GIS with MCDA has resulted in the indication of possible suitable areas for C&D waste disposal, having as a study area the Urban Central Core of Metropolitan Region of Curitiba. Keywords: Geographic Information System. Co

Style APA, Harvard, Vancouver, ISO itp.

31

Basu, Kohinoor. "Feasibility of an Integrated Thin Seam Coal Mining and Waste Disposal System". Thesis, Virginia Tech, 1997. http://hdl.handle.net/10919/9578.

Pełny tekst źródła

Streszczenie:

The depletion of more attractive thicker and easily accessible coal seams in the central Appalachia will direct attention towards the extraction of coal seams thinner than 28 in. This thesis investigates the feasibility of an integrated mining and backfilling system applicable to thin seams. Two conceptual mining systems, namely Auger mining and Self Advancing Miner, have been proposed for this purpose. Both these systems are designed to remotely mine coal from the seams. Several attempts were made in the past to mine coal in a similar fashion but were not very successful due to several problems inherent to thin seams. The lack of effective steering techniques, accurate coal/rock interface and pillar thickness detection techniques were the main shortcomings of the systems. These problems were addressed in the proposed conceptual mining systems. Several coal/rock interface and rib thickness detection techniques currently available in the market or in the prototype stage have been discussed. Recent developments in coal/rock interface detection and direction sensing techniques have good potential in alleviating the previously encountered problems. Sensitivity analyses have been performed to assess the of effect critical mining parameters on the production potential of these systems. The self advancing miner has been found to be more promising than auger mining. Conceptual panels and face layouts for both systems have been included. Two types of filling methods namely pneumatic and hydraulic are considered applicable under thin seam conditions. A backfilling technique using rubber hoses for fill placement can be applied with both methods. Sensitivity analysis have been performed to establish the relationship between face operation cost, filling cost per ton and development cost per foot. Resulting analyses indicate that panel cost per short ton of coal is more sensitive to filling cost than on development cost.
Master of Science

Style APA, Harvard, Vancouver, ISO itp.

32

Yilmaz, Ozge. "Hazardous Waste Management System Design For Turkey". Phd thesis, METU, 2011. http://etd.lib.metu.edu.tr/upload/12613116/index.pdf.

Pełny tekst źródła

Streszczenie:

Hazardous waste management demands detailed planning due to the risks posed by hazardous wastes on public and environment and high investments required. This study aims to provide a framework that leads Ministry of Environment and Forestry (MoEF) in planning of hazardous waste facilities to be built. This framework considers the facility and transport cost along with impacts of hazardous waste management. The linear optimization models for several scenarios are developed in order to evaluate possible approaches in management of hazardous wastes. During cost calculations economy of scale principle is considered. Estimation of impact includes not only population impact but also environmental impact for which a methodology is developed in the scope of this study. This methodology considers the effect of hazardous waste transportation on lakes, rivers, dams, seashores, forests and agricultural areas, which are defined as vulnerable environmental elements. Evaluation of the results suggests that establishment of designated hazardous waste facilities with co-incineration practices and use of transfer stations give most satisfactory outcome. Co-incineration practices decrease incineration costs, which has the highest contribution to overall cost while transfer stations provide great improvement in total impact. Locations for recovery, treatment, incineration facilities and landfills are selected. These selections both confirm decisions made in the past regarding existing locations and become suggestions for locations for new facilities. It is observed that integrated facilities are favored. The importance of countrywide planning should also be underlined. It is believed that results of this study provides a basis to evaluate possible alternatives for further improvement of hazardous waste management system in Turkey that would be most useful to MoEF.

Style APA, Harvard, Vancouver, ISO itp.

33

Grimes, Janet A. "Economic and system feasibility study of municipal waste stowage in underground coal mines". Thesis, This resource online, 1995. http://scholar.lib.vt.edu/theses/available/etd-05092009-040521/.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

34

Judge, David Nixon. "Studies concerning the fate of atrazine and chlorpyrifos in a biobased pesticide waste disposal system". Diss., This resource online, 1996. http://scholar.lib.vt.edu/theses/available/etd-08272007-163645/.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

35

Bari, Quazi Hamidul. "Effect of different modes of aeration on composting of solid waste in a closed system". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1999. http://hub.hku.hk/bib/B30402542.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

36

Quazi, Hamidul Bari. "Effect of different modes of aeration on composting of solid waste in a closed system /". Hong Kong : University of Hong Kong, 1999. http://sunzi.lib.hku.hk/hkuto/record.jsp?B21090415.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

37

Paulsen, Cindy. "Determination of the methanogenic potential of an apple processing wastewater treatment system". Thesis, Link to the online version, 2006. http://hdl.handle.net/10019/1154.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

38

Bojor, Olire Innocent. "Evaluation of an alternative organic waste disposal system in Chevron-Escravos : a case study / O.I. Bojor". Thesis, North-West University, 2008. http://hdl.handle.net/10394/2586.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

39

Mukandi, Melody. "Modelling of a bioflocculant supported dissolved air flotation system for fats oil and grease laden wastewater pretreatment". Thesis, Cape Peninsula University of Technology, 2017. http://hdl.handle.net/20.500.11838/2637.

Pełny tekst źródła

Streszczenie:

Thesis (MTech (Chemical Engineering))--Cape Peninsula University of Technology, 2017.
In the recent past, the poultry industry in South Africa has grown due to an increased demand of poultry products as a result of population growth and improved living standards. Furthermore, this has led to poultry slaughterhouses generating high strength wastewater which is laden with a high concentration of organic and inorganic pollutants from the slaughtering process and sanitation of equipment and facilities. As a result, South Africa has promulgated restrictions and a set of quality standards for effluent discharged into the environment to minimize ecological degradation and human health impact. Hence, there is a need for improved Poultry Slaughterhouse Wastewater (PSW) pre-treatment prior to either discharge into municipal wastewater treatment plants (WWTP) or on-site secondary treatment processes such as anaerobic digesters. Additionally, amongst the pre-treatment methods for Fats, Oil and Grease (FOG) laden wastewater, flotation remains the most popular with Dissolved Air Flotation (DAF) system being the most applied. However, modelling and optimization of a biological DAF system has never been attempted before in particular for a bioflocculant supported DAF (BioDAF) for PSW pre-treatment. Process modelling and optimization involves process adjustment to optimize influential parameters. In this study, Response Surface Methodology (RSM) was used to develop an empirical model of a BioDAF for pre-treatment of PSW, for which a bioflocculant producer including production conditions, flocculant type and its floc formation mechanism, were identified. Twenty-one (n = 21) microbial strains were isolated from the PSW and their flocculation activity using kaolin clay suspension (4g/L) was quantified, with a mutated Escherichia coli (mE.coli) [accession number LT906474.1], having the highest flocculation activity even in limited nutrient conditions; hence, it was used for further analysis in other experiments. Furthermore, the optimum conditions for bioflocculant production achieved using RSM were pH of 6.5 and 36°C conditions which induced instantaneous bioflocculant production with the highest flocculation activity. The bioflocculant produced by the mE.coli showed the presence of carboxyl/amine, alkyne and hydroxyl functional groups, which was indicative that the bioflocculant contained both polysaccharides and some amino acids.

Style APA, Harvard, Vancouver, ISO itp.

40

Taylor, Mike. "The performance of vermicompost filtration : an on-site domestic waste treatment system /". [St. Lucia, Qld.], 2004. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe17846.pdf.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

41

Holtman, Gareth Alistair. "Design, installation, and assessment of a biological winery wastewater treatment system". Thesis, Cape Peninsula University of Technology, 2017. http://hdl.handle.net/20.500.11838/2573.

Pełny tekst źródła

Streszczenie:

Thesis (MTech (Civil Engineering))--Cape Peninsula University of Technology, 2017.
Currently in South Africa, most wastewater from small cellars is pH-adjusted and disposed of via land irrigation. This practice can lead to environmental degradation. There is a need for low cost, low maintenance solutions for the treatment of cellar effluent. Constructed wetlands provide such an option. However, the use of plants is problematic because winery effluent can be phytotoxic. After successful initial laboratory-scale experiments, an in-situ pilot scale biological sand filter (unplanted constructed wetland) system was designed, installed, and used to treat effluent from a small winery in the Western Cape, South Africa. The system is off-grid, totally self-regulating, and uses a modular approach which allows for the addition and subtraction of filter modules within the system to alter treatment capacity, retention time and/or rest filter modules. The system can be easily integrated into existing settling basins and/or retention ponds at small wineries. The biological sand filter was operational for 610 days, and showed promising results. The average chemical oxygen demand removal efficiency was 81% (range: 44-98%) with an average effluent of 324 mg/L, and an average flow rate of 413 L/day after the acclimation (start-up) period. The average hydraulic loading rate after the initial start-up period was 143 L/m3 sand day-1 (range: 67-222/m3 sand day-1), with an organic loading rate of 205 gCOD/m3 of sand day-1 (range: 83-338 gCOD/m3 sand day-1) which resulted in an organic removal rate of 164 gCOD/m3 of sand day-1. There was an average of 67% removal of total phenolics, thereby reducing the potential phytotoxicity of the effluent. In addition, there was a 1.6 times increase in calcium concentration, a 29% decrease in the average sodium adsorption ratio, and complete passive neutralisation of the acidic winery wastewater (final effluent pH range: 6.63 – 8.14. The findings of this study compare well with previous laboratory studies conducted with synthetic and authentic winery effluent. The system can potentially provide a low cost, energy efficient, low maintenance, sustainable means of treating cellar effluent at small wineries. Uptake of this technology may alleviate environmental degradation caused by irrigating land with inadequately treated effluent.

Style APA, Harvard, Vancouver, ISO itp.

42

Choi, Fei. "System dynamics study and assessment on municipal solid waste management for Macao". Thesis, University of Macau, 2012. http://umaclib3.umac.mo/record=b2586273.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

43

Huen, Clay. "Would adopting the ISO 14000 make Hong Kong's solid waste management system more sustainable?" Thesis, Hong Kong : University of Hong Kong, 1998. http://sunzi.lib.hku.hk/hkuto/record.jsp?B19945528.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

44

Van, den Berg Jacobus A. "The utilisation of the ash disposal system as a salt sink : enhancement and optimisation of chemical interactions". Thesis, Stellenbosch : University of Stellenbosch, 2004. http://hdl.handle.net/10019.1/16450.

Pełny tekst źródła

Streszczenie:

Thesis (MScIng)--University of Stellenbosch, 2004.
ENGLISH ABSTRACT: The fine ash produced at the Sasol Secunda Petrochemical Plant is disposed of through a wet ash disposal system. Other process waste streams with high salt concentrations are co-disposed of in the Sasol Secunda ash disposal system. This has led to a steady rise in the salt concentrations of the recycled clear ash effluent (CAE) over the past 17 years. To combat this increase in salt concentrations, the capability of the Sasol Secunda ash disposal system to act as a salt sink, needs to be enhanced. This investigation focussed on ways to enhance the salt removal/retention capabilities of the Sasol Secunda ash disposal system and consisted of the following: • A literature survey of relevant information. • The mixing of different combinations of fine ash, brine and CAE. • Adding CO2 to the fine ash and CAE mixtures. • Investigation to enhance salt precipitation in the CAE and Evaporation dams. • Salt balances and a residence time calculation over the CAE and Evaporation dams. From these investigations it were concluded that the Sasol Secunda ash disposal system could be used as a salt sink for SO4 ions. Up to 43% of the SO4 is removed from the brines after the initial ash/water contact. It was also found that the tubular reverse osmosis (TRO) brine could be used as a carrier medium for the ash. The large amounts of Ca that is leached into the ash water during the mixing of the CAE and fine ash can be prevented by the addition of CO2 to the mixing point. There is usually an increase of 240% in the Ca concentration and this is reduced to only an 8% increase with the CO2 addition. The most feasible precipitation enhancement for the CAE and Evaporation dams is an increase in evaporation. This enhances CaCO3 precipitation, which is the main mechanism for salt removal in the CAE and Evaporation dams. Ca, Na and Cl are retained in the evaporation and CAE dams. SO4 is leached from solid phases in the dams. There is however an overall decrease in the total dissolved solids (TDS) of the ash water. The salt removal of the CAE and Evaporation dams is approximately 57 tons per day. The capability of the Sasol Secunda ash disposal system to act as a salt sink can be enhanced by the addition of CO2 at the mixing point and by increasing the evaporation rate in the CAE and Evaporation dams. Using the TRO brine as carrier medium may also increase the SO4 precipitation capabilities of the Sasol Secunda ash disposal system.
AFRIKAANSE OPSOMMING: Die fynas wat by die Sasol Secunda Petrochemiese Aanleg geproduseer word, word verwyder deur ‘n geslote nat asstelsel. Ander afvalstrome wat hoë konsentrasies soute bevat word ook in die Sasol Secunda asstelsel gestort. Dit het tot gevolg dat daar oor die afgelope 17 jaar ‘n volgehoue styging in die sout konsentrasies van die hergebruikte aswater (genoem CAE – “clear ash effluent”) was. ‘n Manier om hierdie styging in die sout konsentrasies teen te werk, is om die sout verwyderingsvermoë van die Sasol Secunda asstelsel te verbeter. Hierdie ondersoek het gefokus op maniere om die sout verwyderings- /terughoudingsvermoë van die Sasol Secunda asstelsel te verbeter en het die volgende ingesluit: • ‘n Literatuur oorsig van toepaslike inligting. • Die meng van verskillende kombinasies van fynas, soutstrome en CAE. • Toediening van CO2 by die fynas en CAE mengsels. • ‘n Ondersoek na metodes om die soutverwydering in die CAE en Verdampingsdamme te verbeter. • Soutbalanse en ‘n residensie tyd berekening vir die CAE en Verdampingsdamme. Na hierdie ondersoeke kon die gevolgtrekking gemaak word dat die Sasol Secunda asstelsel ‘n sout sink vir SO4 ione is. Tot 43% van die SO4 word verwyder na die aanvanklike as/water kontak. Daar is ook gevind dat die TRO (“tubular reverse osmosis”) soutstroom gebruik kan word as ‘n draer vir die fynas. Die groot hoeveelhede Ca wat in die aswater in loog, kan voorkom word deur die toediening van CO2 by die mengpunt van die fynas en aswater. Daar is normaalweg ‘n verhoging van 240% in die Ca konsentrasie van die aswater en dit word verminder na ‘n skrale 8% met die toediening van CO2. Die mees praktiese metode om die soutverwydering in die CAE en Verdampingsdamme te verbeter, is met die verhoging van die verdamping. Dit sal die neerslag van CaCO3, wat die meeste soutverwydering tot gevolg het, verhoog. Ca, Na en Cl word teruggehou in die Verdampings en CAE damme. SO4 loog uit soliede fases in die damme. Daar is wel ‘n afname in die algehele opgeloste spesies (“TDS”) van die aswater. Die soutverwydering van die Verdampings en CAE damme is ongeveer 57 ton per dag. Die vermoë van die Sasol Secunda asstelsel om as ‘n sout sink gebruik te word, kan verbeter word deur CO2 by die mengpunt by te voeg en die verdampingstempo in die Verdampings en CAE damme te verhoog. Die gebruik van die TRO pekelstroom as draer van die as kan die SO4 neerslag in die Sasol Secunda asstelsel ook verhoog.

Style APA, Harvard, Vancouver, ISO itp.

45

Puentes, Ana Cristina. "Functional elements and human dimensions of a municipal solid waste management system in the Amazon forest the case of Puerto Bermúdez, Peru /". [Gainesville, Fla.] : University of Florida, 2004. http://purl.fcla.edu/fcla/etd/UFE0005120.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

46

Selvaraj, Dinesh Kumar. "Solubility studies on the Na - F - PO4 system in sodium nitrate and in sodium hydroxide solutions". Master's thesis, Mississippi State : Mississippi State University, 2003. http://sun.library.msstate.edu/ETD-db/theses/available/etd-07092003-173535/unrestricted/Dinesh%5FThesis.pdf.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

47

Adefeso, Ismail Babatunde. "Techno-economic analysis of a gasification system using refuse-derived fuel from municipal solid waste". Thesis, Cape Peninsula University of Technology, 2017. http://hdl.handle.net/20.500.11838/2753.

Pełny tekst źródła

Streszczenie:

Thesis (Doctor of Engineering in Chemical Engineering)--Cape Peninsula University of Technology, 2017.
The search for alternatives to fossil fuel is necessary with a view to reducing the negative environmental impact of fossil fuel and most importantly, to exploit an affordable and secured fuel source. This study investigated the viability of municipal solid waste gasification for a fuel cell system. Potential solid fuels obtained from the study in the form of refuse-derived fuel (RDF) had high heating value (HHV) between 18.17 MJ/Kg - 28.91 MJ/Kg with energy density increased from 4142.07 MJ/m3 to 10735.80 MJ/m3. The molecular formulas of RDF derived from Ladies Smith drop-off site, Woodstock drop-off site and an average molecular formula of all thirteen municipal solid waste (MSW) disposal facilities were CH1.43O1.02, CH1.49O1.19, and CH1.50O0.86 respectively. The comparative ratios of C/H were in the range of 7.11 to 8.90. The Thermo Gravimetric Analysis showed that the dehydration, thermal decompositions, char combustions were involved in the production of gaseous products but flaming pyrolysis stage was when most tar was converted to syngas mixture. The simulation of RDF gasification allowed a prediction of the RDF gasification behaviour under various operating parameters in an air-blown downdraft gasifier. Optimum SFR (steam flowrate) values for RDF1, RDF2 and RDF3 were determined to be within these values 2.80, 2.50 and 3.50 and Optimum ER values for RDF1, RDF2 and RDF3 were also determined to be within these values 0.15, 0.04 and 0.08. These conditions produced the desired high molar ratio of H2/CO yield in the syngas mixture in the product stream. The molar ratios of H2/CO yield in the syngas mixture in the product stream for all the RDFs were between 18.81 and 20.16. The values of H2/CO satisfy the requirement for fuel cell application. The highest concentration of heavy metal was observed for Al, Fe, Zn and Cr, namely 16627.77 mg/Kg at Coastal Park (CP), 17232.37 mg/Kg at Killarney (KL), 235.01 mg/Kg at Tygerdal (TG), and 564.87 mg/Kg at Kraaifontein (KF) respectively. The results of quantitative economic evaluation measurements were a net return (NR) of $0.20 million, a rate of return on investment (ROI) of 27.88 %, payback time (PBP) of 2.30 years, a net present value (NPV) of $1.11 million and a discounted cash flow rate of return (DCFROR) of 24.80 % and 28.20 % respectively. The results of the economic evaluations revealed that some findings of the economic benefits of this system would be viable if costs of handling MSW were further quantified into the costs analysis. The viability of the costs could depend on government responsibility to accept costs of handling MSW.

Style APA, Harvard, Vancouver, ISO itp.

48

Belliveau, Thomas F. "Site selective spectroscopy of Eu3+ in the glass ceramic forming system Na2O.CaO.Al2O3.TiO2.SiO2". Thesis, McGill University, 1988. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=75764.

Pełny tekst źródła

Streszczenie:

Compositionally related glasses and ceramics of the Na$ sb2$O$ cdot$CaO$ cdot$Al$ sb2$O$ sb3 cdot$TiO$ sb2 cdot$SiO$ sb2$ system (sphene glass-ceramics) doped with Eu$ sp{3+}$ were examined using site-selective spectroscopic techniques (FLN). In sphene glass-ceramics, Eu$ sp{3+}$ preferentially partitions into the crystalline sphene phase. The partition ratio is concentration dependent, decreasing at higher concentrations, because of the limited solid solubility of Eu$ sp{3+}$ in sphene. The concentration occurs at the time of phase separation; Eu$ sp{3+}$ preferentially enters the more ionic (CaO, TiO$ sb2$)- rich droplet phase which eventually becomes sphene. In sphene, Eu$ sp{3+}$ substitutes for Ca$ sp{2+}$ appearing in three different sites caused by associated charge compensation defects. From an analysis of the FLN spectra of the different glasses, the framework for a model describing the coordination shell of Eu$ sp{3+}$ in oxide glasses is developed. The model suggests that Eu$ sp{3+}$ behaves as a network forming ion or quasi-molecular complex. The model is used to explain qualitative features of Eu$ sp{3+}$ FLN spectra including the dependence of the clustering of points of the major crystal field parameter ratios plot on the relative number of non-bridging oxygen ions and Eu$ sp{3+}$ ions in the glass.

Style APA, Harvard, Vancouver, ISO itp.

49

Ye, Jing. "E-waste management in developing countries through legislation and regulations : a case study of China". Thesis, Loughborough University, 2008. https://dspace.lboro.ac.uk/2134/8032.

Pełny tekst źródła

Streszczenie:

E-waste is an emerging issue driven by the rapidly increasing quantities, the hazards involved and the valuable materials in it. Due to a lack of environmentally sound technologies or equipment and the imperfect e-waste management system, the poor quality e-waste recycling and disposal methods commonly practiced in developing countries now have serious and hazardous effects on the environment and the workers'/residents' health. Additionally, industrialized countries are exporting increasing quantities of e-waste to developing countries, complicating the situation finther. The environmental and health issues caused by e-waste in developing countries have resulted in the search for solutions to address this problem before it becomes worse. The main purpose of this research is to find how legislation and regulations be used to improve management of e-waste in developing countries especially studying a case in China on e-waste management, which is a very helpful example to other developing countries which are also facing the same e-waste'issue. A case study methodology was used in this research. To collect data, semi-structured interviews with officers or experts from key relevant government departments/institutions involved in e-waste management/regulation, from electronic appliance producers, from customers at different levels of the value chain, as well as direct and non-participant observations were carried out in six cities of China. For another perspective, the review of relevant departmental documents/publications was also carried out to multiply the source of data. In this case study the analysis relies largely on qualitative data and interpretive methods, applied to what was found in interviews/observations and what is written down in documents/ literatures. The research found that lack of systernatic and enforceable law and regulations has become the most serious obstacle in the e-waste management system and limited the effective control of e-waste in developing countries. Developing subsidiary regulations and standards could support the enforcement of the main national law and regulations on e-waste management and it could farther urge the development of local regulations to improve the enforceýbility of the national law and regulations. Identifying the principal administrative department and coordinating the cooperation of various departments could avoid the duplication of administrative functions among government departments. It is important to construct monitoring systems to supervise the enforcement of the regulations and construct the standards and registration system to qualify the e-waste recycling and disposal enterprises, the secondhand market of electronic products and the regenerative resources market of reusable materials in ewaste. The economic differences made it possible to formulate special regulations for economically backward areas compared to the, more advanced areas even within one country. Improving the existing e-waste recovery system and regulating the payment system according to the local economic conditions for e-waste recycling and disposal could improve the integrated management of e-waste. Producers as well as government and even consumers should be responsible for e-waste together. The government needs to continuously strengthen regulatory systems to ensure that the huge economic benefits from the e-waste recycling industry are not overshadowed by the negative impact on the workers'/residents' welfare and overall environmental sustainability,

Style APA, Harvard, Vancouver, ISO itp.

50

Grobbelaar, Loreen. "Treatment of biodiesel wastewater in a hybrid anaerobic baffled reactor microbial fuel cell (ABR-MFC) system". Thesis, Cape Peninsula University of Technology, 2019. http://hdl.handle.net/20.500.11838/2812.

Pełny tekst źródła

Streszczenie:

Thesis (Master of Engineering in Chemical Engineering)--Cape Peninsula University of Technology, 2019.
The biodiesel industry produces large volumes of biodiesel wastewater (BDWW) during the purification of crude biodiesel. This wastewater is characterised by high concentrations of chemical oxygen demand (COD), biological oxygen demand (BOD), total suspended solids (TSS), and fats, oils and greases (FOG) which in turn defines BDWW as a highly polluted effluent. The low nitrogen and phosphorous content of BDWW creates an unfavourable environment for the growth of microorganisms, thereby making it difficult to degrade naturally. Biodiesel companies discharge untreated non-compliant wastewater directly to the municipal sewer system. Treatment prior to discharge is a necessity since the disposal of untreated BDWW may raise serious environmental concerns (i.e. disturbance of biological ecosystems) resulting in penalties liable by non-compliant companies due to the implementation of the waste discharge charge system (WDCS) which is regulated by the industrial waste discharge standard limits in South Africa (SA). This study aimed to combine the advantages of the conventional anaerobic baffled reactor (ABR) system with microbial fuel cell (MFC) technology resulting in an innovative technology used to treat high strength industrial BDWW at ambient conditions. Many studies have reported effective treatment of BDWW, however to date literature implementing an ABR equipped with MFC technology has not been reported. The main objectives of the study were to determine which parameters do not meet the industrial wastewater discharge standard limits, whether pH and carbon:nitrogen:phosphorous (C:N:P) ratio adjustments will suffice prior to treatment with the ABR-MFC, the maximum power density (PD) as well as to determine the treatment efficiency of the ABR-MFC.

Style APA, Harvard, Vancouver, ISO itp.

Rozprawy doktorskie na temat „Waste Disposal Systems”

Utwórz poprawne odniesienie w stylach APA, MLA, Chicago, Harvard i wielu innych