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1
Uhlířová, Marcela. "Využití membrán pro zpracování odpadních vod ze zemědělství." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2021. http://www.nusl.cz/ntk/nusl-443232.
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This thesis deals with an agricultural wastewater treatment (liquid digestate) by membrane technology. There is a fundamental description of characteristics of membrane technology with regard to application of agricultural wastewater treatment in this thesis. Experimental device for treatment of liquid digestate is designed and it consists of three steps – microfiltration, ultrafiltration and reverse osmosis. The first step consists of four filters with different pore sizes (80, 25, 10 and 5 µm). The second step is ultrafiltration and the third and key step is reverse osmosis. In the final step monovalent ions such as NH4+ are separated. Reverse osmosis consists of two stage system which results in higher recovery. Three experiments were carried out in order to verify the efficiency of separation dissolved solids.
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Heger, Jan. "Získávání fosforu z fugátu." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2021. http://www.nusl.cz/ntk/nusl-442835.
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The focus of this thesis is the posibility of obtaining phosphorus from liquid digestate. The theoretical part of the thesis is focused on summarizing the current situation regarding phosphorus recovery. The research summarizes the essential information about the method of struvite precipitation, by which phoshphorus is obtained in the form of struvite, which can be further used as a fertilizer. Based on the process information, an experimental device was designed to obtain phosphorus in the form of struvite, corresponding to industry standards. It is a cylindrical vessel with a conical bottom, in which the liquid digestate with the chemicals is mixed with a stirrer. The functionality of the device was tested experimentally on the created device. The results of the experiment were analyzed by XPS method, which confirmed the formation of struvite. For future operation, modifications of the device and pre-treatment of the liquid digestate were proposed, which could improve the whole process and its results.
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Budín, Oto. "Zpracování fermentačních zbytků z bioplynových stanic." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2017. http://www.nusl.cz/ntk/nusl-318762.
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This diploma thesis deals with dewatering technologies of fermentation residues from biogas plants and aims to design an integration of selected technology into the biogas plant. Fermentation residues (or digestate), which are a by-product of anaerobic biomass fermentation in biogas plants, contain a certain amount of nutrients and are usually used as agricultural fertilizers. However, the high-water content in digestate and the associated low nutrient concentration increase the cost of its storage and transport. Dewatering of fermented material could help reduce these costs. The main part of this work included the design of an integration of the selected dewatering technology into the biogas plant – its placement in a process, an addition of necessary appliances, the influence on material and energy flows. In this case, the fermentation residues are processed in two phases. First, a separation of the solid and the liquid fraction by a screw press. The second step is to thicken the liquid digestate by evaporation in a multistage evaporator. Evaluation of the design of a dewatering technology, including its impact on the economy of the biogas plant, is also part of the diploma thesis.
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Knoop, Christine [Verfasser], Thomas [Gutachter] Raab, and Christina [Gutachter] Dornack. "Anaerobic treatment of municipal organic waste from separate collection : digestate properties and substance flows during two-stage digestion and subsequent aerobic treatment / Christine Knoop ; Gutachter: Thomas Raab, Christina Dornack." Cottbus : BTU Cottbus - Senftenberg, 2019. http://d-nb.info/1185489894/34.
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Liman, Martin. "Výměna hmoty kapalina-pára v procesech stripování." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2021. http://www.nusl.cz/ntk/nusl-445374.
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This diploma thesis deals with the solution of ammonia separation from waste raw materials of agricultural production. It focuses on determining the efficiency of desorption from an experimental stripping device depending on the measurement temperature. Ammonia water solutions and liquid digestate samples from technical practice were used to verify the functionality of the equipment. Increasing separation efficiency with increasing temperature has been demonstrated. The device was gradually improved during the measurement for a better profitability of the separation process. The results of the experiments are discussed concerning the theoretical assumptions and compared with other methods of ammonia separation.
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Tolley, M. R. "The biological treatment of liquid wastes containing heavy metals." Thesis, University of Oxford, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.335844.
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Cao, Xinjin. "Heat treatment of liquid metal : precipitation and sedimentation processing of liquid Al-11.5Si-0.4Mg alloy." Thesis, University of Birmingham, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.369168.
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Ang, Choon Jek, and choonjej@yahoo com au. "Treatment of printing ink wastewater using high liquid carryover mode function." Swinburne University of Technology. Environment and Biotechnology Centre, 2005. http://adt.lib.swin.edu.au./public/adt-VSWT20051017.115207.
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The aim of this project is to investigate the feasibility of the use of a novel process of high liquid carryover (HLC) mode flotation to treat wastewater from a cardboard printing and coating plant. This is conducted by characterising the process conditions with the purpose of achieving a set condition that have a low susceptibility to variability in the wastewater composition. Information pertaining to the surface and physical characteristics of the solid contained in the wastewater sample were used to explain the flotation outcomes. Fe(II) was found to be more suited for industrial use as coagulant over the more commonly known coagulants, Al(III) and Fe(III), as it has the advantages of having a constant optimum flotation pH (6.5) regardless of wastewater characteristics, as well as having a much lower detrimental effect on the flotation outcome when present in excess of the minimum requirement for flocculation of wastewater solids. This allows the setting of a coagulant dose (5 mM) that will treat both high and low solids content wastewater samples. The use of cationic surfactant (CTAB) was found to require lower coagulant dosages compared to those required for anionic (SDS) or non-ionic (TericG12A8) surfactants in order to achieve good flotation outcomes. A CTAB concentration of 300 ppm was required to achieve a stable foam that can sustain for a prolonged period to allow solid (in foam)/liquid separation. The optimum batch mode conditions for HLC flotation were found to be pH 6.5, 5 mM Fe(II) and 300 ppm CTAB. This was found to correspond to a small and negative electrophoretic mobility at the wastewater solid surface and large floc size. Batch mode flotation of individual ink components under the optimum conditions for industrial wastewater treatment revealed that the presence of large quantities of either blue or yellow inks in the wastewater can lead to poor removal. Their combined presence, however, did not have detrimental effects. Continuous mode flotation at 5 mM Fe(II), 300 ppm CTAB and pH 6.5 was found to remove above 96% of contaminants at cell residence times of 6 minutes and 88% of contaminants at cell residence times of 1.5 minute. Greater than 87% of the initial wastewater volumes were recovered as treated effluent (i.e. < 13% disposed as waste foam sludge), yielding a waste foam sludge containing between 12 and 17% solids. The best flotation outcomes were achieved when all the wastewater volume entering the flotation cell leaves the cell with the foam.
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Grima, N. M. M. "Kinetic and mass transfer studies of ozone degradation of organics in liquid/gas-ozone and liquid/solid-ozone systems." Thesis, University of Bradford, 2009. http://hdl.handle.net/10454/3351.
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This work was concerned with the determination of mass transfer and kinetic parameters of ozone reactions with four organic compounds from different families, namely reactive dye RO16, triclocarban, naphthalene and methanol. In order to understand the mechanisms of ozone reactions with the organic pollutants, a radical scavenger (t-butanol) was used and the pH was varied from 2 to 9. Ozone solubility (CAL*) is an important parameter that affects both mass transfer rates and chemical reaction kinetics. In order to determine accurate values of the CAL* in the current work, a set of experiments were devised and a correlation between CAL* and the gas phase ozone concentration of the form CAL*(mol/L) = 0.0456 CO3 (g/m3 NTP) was obtained at 20°C. This work has also revealed that t-butanol did not only inhibit hydroxyl radical reactions but also increased mass transfer due to it increasing the specific surface area (aL). Values of the aL were determined to be 2.7 and 3.5 m2/m3 in the absence and presence of t-butanol respectively. It was noticed that the volumetric mass transfer coefficient (kLa) has increased following the addition of t-butanol. Ozone decomposition was studied at pH values of 2 to 9 in a 500 mL reactor initially saturated with ozone. Ozone decomposition was found to follow a second order reaction at pH values less than 7 whilst it was first order at pH 9. When the t-butanol was added, the decomposition of ozone progressed at a lower reaction order of 1.5 for pH values less than 7 and at the same order without t-butanol at pH 9. Ozone decomposition was found significant at high pHs due to high hydroxide ion concentration, which promotes ozone decomposition at high pHs. The reaction rate constant (k) of RO16 ozonation in the absence of t-butanol was determined. The result suggests that RO16 degradation occurs solely by molecular ozone and indirect reactions by radicals are insignificant. The chemical reaction of triclocarban with ozone was found to follow second order reaction kinetics. The degradation of naphthalene using the liquid/gas-ozone (LGO) system was studied. This result showed that hydroxyl radicals seemed to have limited effect on naphthalene degradation which was also observed when a radical scavenger (t-butanol) was used. Reaction rate constants were calculated and were found around 100 times higher than values reported in the literature due to differences in experimental conditions. From the results of the experimental investigation on the degradation of methanol by ozone it was found that the rate constant (k) of the degradation reaction increased at pH 9. The reaction stoichiometry was found to have a value of 1 mol/mol. The two steps of the liquid/solid-ozone (LSO) system were studied on beds of silica gel and a zeolitic material (D915) and the ozone adsorption process was modeled and found that particle rate controls ozone adsorption step but liquid rate controls the water treatment step. Ozone desorption with pure deionised water was studied. The water flow rate was found to accelerate the desorption rates but pH was found to decrease the desorption rates. In contrast, the effect of pH was insignificant in the presence of t-butanol. Determination of the adsorption isotherms for RO16, naphthalene and methanol revealed that RO16 did not exhibit adsorption on silica gel, but both naphthalene and methanol showed adsorption on D915 described by Langmuir model.
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Yawson, Selina Kuukuwa. "Dairy manure treatment using solid-liquid separation and microwave enhanced advanced oxidation process." Thesis, University of British Columbia, 2010. http://hdl.handle.net/2429/29232.
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Dairy manure treatment, using solid-liquid separation and microwave enhanced advanced oxidation process (MW/H₂O₂-AOP), was investigated. The objectives of the research were to determine: 1) the nutrient and metal composition of solid and liquid fractions of raw dairy manure following solid-liquid separation, 2) the effects of MW/H₂O₂-AOP operating factors of temperature, hydrogen peroxide (H₂O₂) dosage, acid concentration and heating time on sugar production and nutrient release from solid dairy manure.
Solid-liquid separation of raw dairy manure, using a 1mm laboratory sieve, showed that solid fractions had a higher composition of TS and volatile solids (VS), while the liquid fractions were richer in nutrients and metals. Laboratory separation by screening alone was not effective in removing high amounts of nutrients and solids from the raw manure.
Screening experiments were conducted using cellulose fibers to study the effects of temperature, acid concentration, H₂O₂ dosage and heating time on sugar production, with the aim of applying the results to dairy manure lignocellulosic material. Sugar production increased when acid concentration was increased from 1% to 3%, but decreased with an increase to 10%. More sugar was produced at 160°C compared to 120°C. Sugar production decreased with increasing time.
Microwave irradiation of solid dairy manure at pH 2, temperatures of 80, 120 and 160°C, H₂O₂ dosages of 0 to 0.50 mL, and heating times of 10 to 20 min, showed that more sugars were released at higher temperatures. Temperature and hydrogen peroxide dosage were identified as the most important factors affecting solubilization of phosphorus and ammonia. Subsequently, a two-stage acid hydrolysis process, using MW/H₂O₂-AOP, was used to investigate sugar production and solubilization of phosphorus and ammonia from solid dairy manure at: 3% acid concentration, 120 and 160°C, 0 and 2 mL H₂O₂ and heating times of 20 and 60min. To enhance sugar production from solid dairy manure, the microwave should be operated at higher temperatures and shorter heating times with no H₂O₂. For ammonia and phosphorus solubilization, higher temperatures and longer heating times, in the presence of H₂O₂, would be advantageous.
MW/H₂O₂-AOP is therefore an efficient means for treating diary manure for nutrient recovery.
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Ferguson, Paul David. "A unified treatment of chiral separations in capillary electrophoresis and liquid phase chromatography." Thesis, University of York, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.387566.
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Murphy, M. E. "A comparison of solid and liquid culture in tuberculosis diagnosis and treatment monitoring." Thesis, University College London (University of London), 2016. http://discovery.ucl.ac.uk/1485825/.
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Tuberculosis (TB) poses a significant challenge for global health. Developing countries most burdened by disease have insufficient laboratory resources and limited capacity to conduct clinical trials. This thesis aims to investigate microbiological methods currently employed in TB programmes to compare their value in diagnosing TB and monitoring treatment using data from smear-positive patients enrolled in the REMoxTB study. As TB culture remains out-of-reach in many settings, diagnosis continues to depend on sputum smear microscopy. Early morning samples are considered better than spot samples. However, the data presented show that spot samples have a higher positive yield and greater sensitivity for solid and liquid culture. This evidence does not support guidelines requiring early morning samples which inconvenience patients and complicates trial enrolment. The data also show a reducing correlation between smear microscopy and culture on solid and liquid media as treatment progresses. These findings question the use of smear microscopy as a proxy for culture during treatment which may prompt inappropriate treatment extensions or retreatments. Comparing solid and liquid culture, the analyses show that liquid culture is faster and more sensitive. The clinical significance of this increased sensitivity throughout treatment is uncertain, and some samples negative in liquid culture remain positive on solid culture. The relationship between solid and liquid culture changes during treatment suggesting they differentially support the metabolic requirements of changing mycobacterial populations. The value of measures of pre-treatment mycobacterial load are investigated and show they are poorly predictive of microbiological responses during treatment in either culture media. Better indicators of treatment response are required which reflect mycobacterial population dynamics. Increasing availability of TB culture would of great benefit. The data show that the incubation times for liquid cultures, particularly for diagnostic samples, may be significantly reduced without loss of sensitivity, which could increase laboratory capacity and remove barriers to implementation. Future work will investigate whether these findings are generalisable to smear-negative patients and assess their value in predicting long-term treatment outcomes.
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Liu, Dun. "Water treatment by adsorption and electrochemical regeneration : development of a liquid-lift reactor." Thesis, University of Manchester, 2015. https://www.research.manchester.ac.uk/portal/en/theses/water-treatment-by-adsorption-and-electrochemical-regenerationdevelopment-of-a-liquidlift-reactor(fdf6248a-90a1-4950-87d7-14fc501ab35b).html.
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Efficient and economic treatment of low concentration organic pollutants in water, wastewater or industrial process streams is normally very difficult to achieve. Activated carbon has been widely used for contaminant adsorption, but there are problems associated with its regeneration. In this work, a novel, non-porous, highly-conducting graphite intercalation compounds material (GIC) is used. The use of such an adsorbent can significantly reduce the time required to achieve both equilibrium and electrochemical regeneration. This character allows the design of an innovative treatment process that can adsorb contaminants and electrochemically regenerate itself simultaneously within a single unit. A novel liquid-lift reactor for water treatment by an adsorption and electrochemical regeneration process is developed in this work. Batch experiments are carried out to determine the adsorption kinetics and equilibrium isotherm of adsorption Acid Violet 17 onto the GIC adsorbent. The experimental kinetic data are analyzed using the pseudo-first order, pseudo-second order, intra-particle diffusion and three-stage kinetic models. The linear pseudo-second order model offers the highest r2 correlation coefficient. The experimental isotherm data are analyzed using Langmuir, Freundlich and Tempkin isotherm models. The non-linear Langmuir model gives the highest r2 correlation coefficient. High regeneration efficiency (more than 90%) over a number of cycles is obtained by passing a charge of 6.4 C g-1 of the GIC adsorbent, at a current density of 5 mA cm-2 using a batch, sequential adsorption (60 min) and electrochemical regeneration (30 min) process. The simultaneous adsorption and regeneration process indicates that 100 % AV 17 can be removed in 60 min (4L of 100 mg L-1 AV 17 solution, 140g of the GIC adsorbent, current density of 5mA cm-2). The flow behaviour in the electrochemical reactor has been studied using a pulse tracer technique. The residence time distribution shows that the flow behaviour in the liquid-spouted reactor can be regarded as a plug flow in series with a continuous stirred tank reactor. For the batch adsorption system, a “parallel adsorption barren well hypothesis” is proposed in this thesis. For the batch simultaneous adsorption and electrochemical regeneration system, a multi-parameter model is proposed in this thesis.
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Miklas, Václav. "Integrace technologie pro zahušťování digestátu v bioplynové stanici." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2018. http://www.nusl.cz/ntk/nusl-377758.
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This diploma thesis is mainly focused on the digestate thickening in a biogas plant. First, overview of the biogas technology in the Czech Republic is presented. Furthermore, problems with waste heat utilization and processing of fermentation residues (digestate) are described in more detail. Based on the research, multi-stage flash (MSF) evaporation was chosen as the technology for the digestate thickening. The main part deals with the integration of the chosen technology into a biogas plant process. The programming language Python was used to simplify the given task. In the preliminary stage, a complex mathematical model of a biogas plant was created, focusing particularly on the mass and energy balances. Subsequently, a computational model of the MSF evaporator was programmed. A procedure for the integration was suggested using the sensitivity analyses. Additionally, the model of a biogas plant was extended with the MSF evaporator. The key outcome of the thesis is a technical-economic analysis in which the impact of digestate transport price and electricity feed-in tariff on payback period is investigated. The results suggest profitability of MSF evaporator for biogas plants without subsidized feed-in tariff. Contrastingly, installation of MSF evaporator in older biogas plants with subsidized feed-in tariff can be economically viable only in cases of significantly longer transport distances.
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Bailey, Andrew Douglas. "An exploratory investigation of crossflow microfiltration for solid/liquid separation in biological wastewater treatment." Master's thesis, University of Cape Town, 1989. http://hdl.handle.net/11427/21915.
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This thesis contains the results and discussion of an exploratory investigation into the application of Crossflow Microfiltration (CFMF) for solid/liquid separation in biological wastewater treatment systems. The principal objective of the study was to assess the influence of CFMF on the performance of identified biological wastewater treatment systems. It was not the objective to optimise filtration performance. A literature review indicated that the crossflow mode of filtration has been widely accepted as a unit operation in the fermentation industry. The filtration mode is now being applied not only for solid/liquid separation but also for separations on a molecular and ionic level. Very few applications of crossflow filtration in the context of biological wastewater treatment solid/liquid separation are reported in the literature. The reasons for this limited experience would appear to be the scale involved and the perceived high costs; separations in the fermentation industry are usually conducted at relatively small scale (laboratory or pilot-scale) and involve high-value products, justifying high capital and operating costs. Also, the high level of separation performance attained is perhaps not necessary for many wastewater treatment applications. No doubt these reservations are largely valid. However, these arguments cannot be applied equally to all filtration methods and wastewater treatment schemes. For example, the costs of microfiltration are substantially less than ultrafiltration or reverse osmosis, and in certain cases effluents with extremely low suspended solids contents may be required. In the light of these observations an investigation of CFMF for solid/liquid separation in biological wastewater treatment systems appears justified. Two biological treatment systems were selected for study: the Upflow Anaerobic Sludge Bed (UASB) reactor and the Activated Sludge system. The envisaged benefits accruing from the application of CFMF were different in each case.
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Orner, Kevin Daniel. "Removal and Recovery of Nutrients from Wastewater in Urban and Rural Contexts." Scholar Commons, 2019. https://scholarcommons.usf.edu/etd/7880.
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Efforts to remove and recover nutrients from wastewater are motivated by the United Nations Sustainable Development Goals and the National Academy of Engineering Grand Challenges of Engineering. Of the seventeen Sustainable Development Goals (SDGs), multiple SDGs relate to managing nutrients in wastewater. SDG 6, which is to “ensure availability and sustainable management of water and sanitation for all,” contains targets that aim to improve water quality by reducing pollution, halve the amount of untreated wastewater released to the environment, and increase recycling and safe reuse of wastewater (UN, 2017). SDG 2 seeks to improve food security and SDG 12 seeks to sustainably manage natural resources. Similarly, the National Academy of Engineering Grand Challenges of Engineering highlight managing the nitrogen cycle and providing access to clean water (NAE, 2019).
Centralized wastewater treatment plants (WWTPs) have historically been designed to remove nutrients (such as nitrogen and phosphorus) and other contaminants prior to discharge. Modern wastewater treatment practices integrate recovery of resources including nutrients, energy, and water. The many available technologies, coupled with competing priorities, can complicate community decision-making on the choice of technology and the scale at which to implement the technology (i.e. building, community, or city), as well as determining how new upstream treatment may affect existing downstream treatment. Technologies that recover energy or manage nutrients such as anaerobic digestion, struvite precipitation, and microbial fuel cells can be implemented at a variety of scales in urban settings and may also be viable for influent types such as agricultural waste. Therefore, the overall goal of this dissertation is to contribute to the achievement of multiple sustainable development goals through the removal and recovery of nitrogen and phosphorus from a variety of influents at a variety of scales.
One type of decision-making tool that assists in the choice of nutrient management technologies is a House of Quality. I developed a tool based on the House of Quality that integrated multiple priorities at three scales in a sewershed and produced rankings that generally align with current wastewater treatment practice. Accordingly, top-ranked city-scale technologies are those commonly employed (e.g. A2O, oxidation ditch) that use the dissolved organic carbon present in the wastewater to drive denitrification. Similarly, conventional treatment (e.g. flush toilet connected to a sewer) is ranked highest at the building scale because of its easy maintenance, small footprint, and inoffensive aesthetics. However, future trends such as technology development will likely affect the technologies, weightings, and scores and therefore improve the ranking of novel and emerging technologies. This trend may be amplified by the implementation of test beds, which can provide opportunities to improve the technical characteristics of developing technologies while minimizing risk for municipalities.
The House of Quality planning tool was utilized in an in silico case study to analyze nutrient management technologies at three scales across the Northwest Regional Water Reclamation Facility sewershed in Hillsborough County, FL. The study demonstrated that employing treatment technologies upstream from the centralized wastewater treatment (i.e. building-scale source separation and community-scale technologies) could reduce nitrogen loading to the mainstream treatment train by over 50%. Sidestream treatment (i.e. the liquid effluent of anaerobic digestion that typically recycles back to the beginning of the mainstream treatment process) has minimal impact in nitrogen reduction, but is effective in reducing phosphorus loading to the mainstream due to high quantities of phosphorus recycling back to the head of the plant. These results can inform decision-makers about which context-specific nutrient management technologies to consider at a variety of scales, and illustrate that sidestream technologies can be the most effective in reducing phosphorus loading while building- and community-scale technologies can be most effective in reducing nitrogen loading to the centralized treatment plant.
Struvite precipitation and microbial fuel cells (MFCs) can be used in combination to manage nutrients and recover energy in sidestreams of centralized WWTPs. Because the liquid effluent from engineered struvite precipitation often contains high concentrations of total nitrogen, I constructed and demonstrated a fixed-film nitrification reactor and a two-chambered MFC to further reduce total nitrogen and recover energy. The primary benefit of the MFC in the technology demonstrated here is not its ability to produce energy, but rather its ability to remove additional nitrogen through nitritation and denitritation. The sidestream nutrient removal prevents nutrients from returning to mainstream treatment, reducing operational costs. Such improvements to wastewater treatment processes can facilitate the transition to the resource recovery facility of the future by becoming a net-energy producer while also achieving the simultaneous benefits of nutrient recovery/removal and reduced costs associated with mainstream treatment.
Nutrients and energy can also be recovered in agricultural settings. In this dissertation I studied an agricultural waste treatment system comprising a small-scale tubular anaerobic digester integrated with a low-cost, locally produced struvite precipitation reactor. This study investigated two digesters that treated swine waste in rural Costa Rica. I also facilitated construction of a pilot-scale struvite precipitation reactor that was built on site using local labor and local materials for approximately $920. Local products such as bittern (magnesium source) and soda ash (base) allowed for the production of struvite, a fertilizer that can replace synthetic fertilizer for rural farmers. Liquid-phase concentrations of PO43–-P and NH4+-N in agricultural wastewater increased by averages of 131% and 116%, respectively, due to release from the swine waste during anaerobic digestion. Despite this increase in liquid-phase concentrations, an average of 25% of total phosphorus and 4% of total nitrogen was removed from the influent swine manure through sedimentation in the digesters. During struvite precipitation, an average of 79% of PO43–-P and 12% of NH4+-N was removed from the waste stream and produced a solid with percentages (mass basis) of Mg, N, P of 9.9%, 2.4%, and 12.8%, respectively, indicating that struvite (MgNH4PO4) was likely formed. The treatment system offers multiple benefits to the local community: improved sanitation, removal of nutrients to prevent eutrophication, recovery of struvite as a fertilizer, and production of a final effluent stream that is suitable quality to be used in aquaculture. These are examples of how, more generally, quantifying nutrient recovery from agricultural waste and understanding recovery mechanisms can facilitate progress toward multiple sustainable development goals by improving sanitation, promoting sustainable management of wastes and natural resources, improving food security, and supporting local ecosystems.
Managing nutrients from a variety of influent types at different scales can contribute to the achievement of multiple sustainable development goals. Worldwide trends of population growth and resource depletion highlight the need for models to easily allow decision-makers the ability to understand the fate of nutrients and implement infrastructure accordingly.
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Hou, Xiangting. "DIETARY SUPPLEMENT WASTEWATER TREATMENT BY BIOLOGICAL METHODS." Cleveland State University / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=csu1326295666.
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Prantsidou, Maria. "Plasma methods for the clean-up of organic liquid waste." Thesis, University of Manchester, 2014. https://www.research.manchester.ac.uk/portal/en/theses/plasma-methods-for-the-cleanup-of-organic-liquid-waste(9dab7afe-fcfa-44d1-97f5-c9e1340c96df).html.
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This thesis has studied the low-temperature atmospheric pressure plasma as a potential technological application for the degradation of waste oils. The study has been approached initially by investigating the degradation of oil in gas phase only, in order to understand the gas chemistry and elucidate the plasma-chemical degradation mechanism. Gaseous odourless kerosene and dodecane have been used as simulants to waste oil and their plasma-chemical degradation has been studied using a BaTiO3 packed bed plasma reactor and a gliding arc discharge reactor. Kerosene showed similar degradation behaviour to dodecane and the latter one was chosen as a surrogate to allow quantitative analysis. The dodecane plasma degradation efficiency and the distribution of end-gaseous products have been studied under these two reactors in different gas compositions. Optical emission spectroscopy was used to identify intermediate excited species and calculate the rotational and vibrational temperature profiles. Differences in the dodecane degradation gas chemistry between the packed bed and the gliding arc plasma are discussed and postulated mechanisms are presented for each condition. Gliding arc discharge demonstrates higher degradation efficiency and it will be used mainly for the plasma-liquid treatment. The plasma-liquid dodecane treatment is firstly studied using argon dielectric barrier discharge. The effect of different reactor configuration, humidity and temperature to the discharge characteristics and degradation efficiency will be discussed. The study of the liquid dodecane degradation is extended by using the gliding arc discharge. Using N2 and Ar in both dry and humid conditions for the batch treatment of dodecane, the degradation efficiency, gas chemistry and liquid chemistry are discussed and correlated to the gas chemistry observed during the plasma treatment of gaseous dodecane under the same conditions, in order to gain an overall understanding of the plasma-liquid clean-up process. Finally, the gliding arc plasma treatment of liquid dodecane is studied using the recycling method and shows a significant improvement to the degradation efficiency.
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Dougherty, Mark. "Nitrogen values of liquid dairy manure and dry broiler litter as affected by preservation treatment." Thesis, Virginia Tech, 1995. http://hdl.handle.net/10919/40654.
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Barr, Christopher James. "Biochemical Saccharification of Ionic Liquid Pretreated Biomass: an Examination of Treatment Parameters and Enzyme Requirements." University of Toledo / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1372415335.
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Hong, Yanjuan. "Enhanced Biological Phosphorus Removal for Liquid Dairy Manure." Thesis, Virginia Tech, 2009. http://hdl.handle.net/10919/46067.
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Enhanced biological phosphorus removal (EBPR) has been widely used in municipal wastewater treatment, but no previous studies have examined the application of EBPR to treat dairy manure. This study was conducted to evaluate the (i) performance of pilot-scale EBPR systems treating liquid dairy manure, to balance the ratio of nitrogen to phosphorus in manure to meet crop nutrient requirements, (ii) effects of dissolved oxygen and solids retention time on the efficiency of EBPR, and (iii) effectiveness of gravity thickening for reducing the volume of harvested EBPR aerated mixed liquor.
Two pilot-scale EBPR systems were used in this study. The ratio of the manure chemical oxygen demand expressed as volatile fatty acids to phosphorus used ranged from 18:1 to 45:1. The phosphorus removal efficiencies of the EBPR system were investigated at three solids retention times (4, 6 and 10 d), and three dissolved oxygen levels (3, 4 and 6 mg O2/L). The total phosphorus removal was highest (84%) at 10 d solids retention time and lowest (63%) at 4 d solids retention time. The sludge from the 6 d solids retention time tests had better sludge settling characteristics with a sludge volume index of 62 mL/g compared to 80 mL/g for the 4 d solids retention time. The EBPR system achieved 90% dissolved reactive phosphorus removal when the system
was operated at 4 mg O2/L, and the ratio of nitrogen to phosphorus in effluent increased to about 5:1, which was higher than the normal ratio in dairy manure. On the other hand, phosphorus removal performance deteriorated when dissolved oxygen level was 3 mg O2/L. In the gravity thickening tests, 93-95 % total suspended solids (TSS) was removed from the settled supernatant, with 1.2 to 1.54 % total solids (TS) in the settled solids after 90 min gravity-induced thickening. The extent of phosphorus release during gravity thickening process needs to be further investigated.Master of Science
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Butler, Erick Benjamin. "Biological Treatment of Dietary Supplementary Wastewater." Cleveland State University / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=csu1264479316.
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Wang, Gang. "Microbubble dynamics in the presence of various surfaces due to strong ultrasonic treatment of a liquid." Thesis, McGill University, 2010. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=86755.
Full textAbstract:
The dynamics of a micron-sized gas bubble near a rigid solid boundary and the interaction of two microbubbles in a liquid under a high-intensity ultrasonic field are studied numerically in this thesis. The solid boundary can be a planar wall, a solid particle or two adhered solid particles. The micron-sized gas bubble can be at a distance from the solid boundary or it can be attached to the solid boundary. A two-dimensional numerical technique, based on the finite element method (2D-FEM), has been developed which solves the velocity potential in the form of Laplace's equation in the presence of a fast moving free-surface boundary due to the volumetric oscillations of the bubble. The developed method can solve accurately and efficiently the complex bubble dynamics problem. Because of the lack of similar work in the literature, for some limiting cases of the present work, the numerical results are compared with the published results and good agreements are found.The study of the bubble dynamics in this work starts with the expansion phase of the bubble, for an initial bubble radius around the resonance size. After the expansion phase the bubble goes through the contraction phase and the simulations are stopped when the bubble collapses. For the sound pressure amplitude and frequency considered here, in most of the situations the bubble collapses during its first contraction phase, and some bubbles are seen to rebound and collapse thereafter. When the bubble collapses, a high-speed liquid jet is formed. The direction of the jet can point to the solid/free surface, or point away from the solid/free surface. The shape of the liquid jet may be spike-shaped or annular-shaped. During the collapse of the bubble, a high-pressure region is formed at the root of the liquid jet. Numerical results show that the high-pressure zone can be responsible for the formation of the liquid jet, as well as for the high value of the jet speed. The liquid jet can strike the solid particle, producing a high stagnation pressure region, which can disperse the particle and accelerate it. Numerical results also show that the size and shape of the particle, as well as the size of another coexistent bubble, can affect the velocity, the shape, and the direction of the liquid jet.
The present modeling results concerning microbubble dynamics have shown to explain successfully some sonoeffects in a liquid, such as the dispersion of solid particles, the formation of high-speed liquid jets, the generation of high-pressure zones, and the evolution of bubble shapes.
La dynamique d'une bulle de gaz, ayant une taille de l'ordre du micron, près d'une frontière pleine rigide et l'interaction de deux microbulles dans un liquide sous un champ ultrasonique à haute intensité sont étudiées numériquement dans cette thèse. La frontière pleine peut être un mur planaire, une particule solide ou deux particules collées. La microbulle de gaz peut être à une distance de la frontière pleine ou elle peut être attachée à la frontière pleine. Une technique numérique bidimensionnelle, basée sur la méthode des éléments finis (2D-FEM) a été développée. Elle permet de résoudre le potentiel de vitesse sous forme d'équation de Laplace en présence d'une frontière de libre-surface se déplaçant rapidement sous l'effet des oscillations volumétriques de la bulle. La méthode développée peut résoudre exactement et efficacement le problème complexe de dynamique de bulle. En raison du manque de travail semblable dans la littérature, pour quelques cas de limitation du travail actuel, les résultats numériques ont été comparés aux résultats édités et de bonnes concordances ont été trouvées.
L'étude de la dynamique de bulle dans ce travail commence par la phase d'expansion de la bulle, pour un rayon initial de bulle autour de la taille de résonance. Après la phase d'expansion, la bulle passe par la phase de contraction et les simulations sont arrêtées quand la bulle s'effondre. Pour l'amplitude de la pression acoustique et la fréquence considérées dans cette recherche, dans la plupart des situations l'effondrement de la bulle a lieu pendant sa première phase de contraction. Quelques bulles ont rebondi pour s'effondrer ensuite. Quand la bulle s'effondre, un jet de liquide à grande vitesse est obtenu. Le jet peut être dirigé vers la surface pleine/libre, ou au contraire s'en éloigner. Le jet de liquide peut être sous forme de pics ou annulaire. Pendant l'effondrement de la bulle, une région à haute pression est formée à la source du jet de liquide. Les résultats numériques prouvent que la zone à haute pression peut être responsable de la formation du jet liquide ainsi que de sa vitesse élevée, Le jet liquide peut frapper la particule solide et produire une région de pression de stagnation élevée qui peut disperser la particule et l'accélèrer. Les résultats numériques prouvent également que la taille et la forme de la particule, comme la taille d'une autre bulle co-existante, peuvent affecter la vitesse, la forme, et la direction du jet liquide.
Les résultats de modélisation de la dynamique de microbulle ont permis d'expliquer avec succès quelques phénomènes dans un liquide, telles que la dispersion des particules solides, la formation de jets de liquide se déplaçant à grande vitesse, la génération des zones à haute pression, et l'évolution des formes de la bulle.
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Likes, Wendy. "Feasibility study of liquid-based cytology for post-treatment surveillance of patients with vulvar intraepithelial neoplasia." View the abstract Download the full-text PDF version, 2009. http://etd.utmem.edu/ABSTRACTS/2009-024-Likes-index.htm.
Full textAbstract:
Thesis (Ph.D.)--University of Tennessee Health Science Center, 2009.Title from title page screen (viewed on August 27, 2009). Research advisor: Donna Hathaway, PhD. Document formatted into pages (ix, 43 p. : ill.). Vita. Abstract. Includes bibliographical references (p. 34-37).
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Radwan, Badreddin. "Treatment of a Liquid Al-Si Alloy : Quality Control and Comparison of Two Melt Degassing Processes." Thesis, Tekniska Högskolan, Jönköping University, JTH, Material och tillverkning, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-48236.
Full textAbstract:
Products manufactured by aluminium casting have become very popular and already replaced many parts that were once produced by iron and steel casting. This trends upwards especially in the automotive industry as it has become extremely important to reduce vehicle weight due to environmental requirements and economical aspects. This popularity of aluminium alloys could be ascribed to their light weights and many other advantages including excellent castability, good corrosion resistance, good thermal and electrical conductivity, good machinability, low melting temperatures and minimal gas solubility with the exception of hydrogen. The most important alloy group among casting alloys is Aluminium Silicon (Al - Si). Al-Si alloys must undergo a specific melt treatment procedure prior to casting. This treatment consists of several steps including degassing of hydrogen, grain refinement and eutectic modification. The aim of this study is to make an assessment of the metal treatment process of an (Al-Si) casting alloy at Unnaryd Modell AB for the purpose of improving the melt conditions and thus the quality of the final product. A rotary degasser provided by Foseco is also tested instead of the traditional tablet degassing method to see if this technique would result in any significant improvement of the melt quality. The results show that Unnaryd modell AB follows a proper treatment routine. It shows moreover that the rotary degassing is superior to the tablet degassing in many aspects including the level of degassing achieved, time efficiency, environmental consideration and personnel security.
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Liu, Qing, and 刘晴. "Effect of Tian Xian Liquid on growth inhibition in colon cancer and moderation of 5-fluorouracil-induced myelosuppression." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2010. http://hub.hku.hk/bib/B45587188.
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Nguyen, Jill, and Sarah Workinger. "Evaluation of prophylactic voriconazole and posaconazole concentration monitoring and dose changes in liquid and solid transplant patients." The University of Arizona, 2012. http://hdl.handle.net/10150/623664.
Full textAbstract:
Class of 2012 AbstractSpecific Aims: The primary aim of this study was to determine the incidence of posaconazole and voriconazole concentration monitoring that occurs in transplant patients receiving antifungal prophylaxis therapy. The secondary aim was to determine whether voriconazole and posaconazole serum concentrations were used for dose adjustments. Methods: Patients status post either a liquid or solid organ transplant over the age of 1 year who received invasive fungal infection prophylaxis with either posaconazole or voriconazole between the dates of February 1, 2010 through January 31, 2011 while admitted to academic medical center were included in this descriptive retrospective study. This study has been approved by the Institutional Review Board. Data collected on each subject included demographic information, type of transplant, posaconazole or voriconazole concentrations, and duration and dosage adjustments. Main Results: 54 subjects were identified who received either voriconazole or posaconazole for fungal prophylaxis after transplant. For subjects who were prescribed posaconazole (N = 8), concentration monitoring was performed in 50% of subjects and 0% of posaconazole dose adjustments were based on concentrations. For subjects who were prescribed voriconazole, concentration monitoring and dose adjustments based on voriconazole concentrations were performed in 20% and 78% of subjects respectively. Adverse outcomes associated with the use of antifungal therapy were reported in 0% of the posaconazole therapy group and 17% of the voriconazole therapy group. Conclusions: Both posaconazole and voriconazole concentrations were obtained from patients who were receiving antifungal therapy for invasive fungal infection prophylaxis. Adjustments of prophylactic doses are not well characterized.
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Maxwell, Deborah. "REMEDIATION OF HEAVY METAL CONTAMINATION IN SEDIMENTS: APPLICATION OF IN SITU TREATMENT UTILIZING EMULSIFIED LIQUID MEMBRANE AN." Master's thesis, University of Central Florida, 2007. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/4329.
Full textAbstract:
Heavy metal contamination of soils, sediments and groundwater presents an ongoing source of hazardous and persistent environmental pollution. How best to remediate these contaminants is the impetus of continuing research efforts. Methods include containment, ex situ and in situ techniques. A successful in situ method utilizing a combination of emulsified liquid membranes, ELM, and zero-valent metal, ZVM, and bimetals has demonstrated impressive heavy metal reduction in 100 ppm solutions of Cd, Cu, Ni, Pb, Cr and U. This promising in situ method has been employed by the Industrial Chemistry Laboratory at the University of Central Florida and it has demonstrated considerable success in treating several environmental threats. Contaminated soils, surfaces, sediments and groundwater with offending agents such as trichloroethene, polychorobiphenyls and heavy metals have been treated utilizing emulsified liquid membrane systems containing zero-valent iron or bimetal particles. In vial studies, lead spiked sediments have shown repeatable 60% removal of lead after seven days of treatment. A persistent pattern emerged at ten days whereupon remediation levels began to drop. The current study was established to determine the reason for the decline at ten days and beyond. Questions addressed: Does the formation of an impeding oxide layer diminish the remediation capacity of the iron/magnesium system? Does the emulsion reach a maximum capacity to withdraw the contaminant? Do the soil components or the soil structure interfere with the access to the contaminant? This study has yielded insight into the reasons emulsified liquid membrane systems containing zero-valent metals achieved maximum lead removal at day seven, and thereafter begin to lose their effectiveness. A three part study was implemented to address and to answer the three questions pertaining to the consistent pattern of diminishing remediation levels exhibited at day ten and beyond. Initially, from Study I results it appeared that the formation of an impeding oxide layer on the bi-metal which was inside the emulsion droplet and which plated or precipitated with the lead was not occurring at day ten. Results indicated that the iron/magnesium was still capable of removing lead. Furthermore, from Study II results the emulsion dose injected appeared adequate to remove the lead, meaning that the emulsion had not reached its maximum capacity for remediation. The emulsion dose was not a limiting factor. Lastly, Study III results seemed to indicate that the drop in remediation after day seven pertained to the soil structure. There appeared to be some merit to the idea that with aging of the sediment, the lead was diffusing and migrating to some inaccessible interior sites within the sediment particles. Additionally, indications from day ten and day fourteen delineated that a second emulsion dose injection might restore lead removal levels to approach those first observed at day seven and consequently be a useful field application. In order to explore the effectiveness of injecting a second dose of emulsion, another vial study was implemented. The typical pattern of observing sixty percent maximum lead removal at day seven was observed. In separate groups, a second injection of emulsion was added at day five, and then for another vial series, a second dose was added at day seven. The second emulsion dose treatment for either day five or day seven did not yield any increases in percent lead removal. Another theory emerged after viewing micrographs of recovered iron/magnesium compared with fresh ball-milled bimetal. In addition, scanning electron microscopy appeared to confirm the explanation that the emulsified zero-valent metal system might be compromised after day seven. This would lead to exposure of the iron/magnesium to the air and the elements. Corrosion of the bimetal might be occurring. With time, release of the plated or precipitated lead back into the sediment mixture could follow. The results of Study I had led to the conclusion that an impeding oxide layer had not formed; however, this conclusion may have been premature because the recovered iron/magnesium was exposed to lead solution in the vial study. Perhaps if the recovered iron/magnesium was inserted back into an emulsion and injected into lead spiked sediments the percent lead removed might give a more accurate picture of the iron/magnesium's capability to continue performing remediation. Remediation of sediments contaminated with lead is a complicated task because of the complex nature of sediment components. Emulsified liquid membranes utilizing zero-valent bimetals has repeatedly demonstrated impressive results at day seven; however, this treatment method is not without its limitations. Optimal results appear to be gained at day seven after emulsion injection. The bimetal and plated or precipitated lead must be removed at that point; otherwise the effective remediation of the contaminant is progressively reversed.M.S.
Department of Chemistry
Sciences
Industrial Chemistry MS
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Murch, Sarah Louise. "The role of liquid chromatography-high resolution mass spectrometry in the diagnosis and treatment of substance misuse." Thesis, King's College London (University of London), 2018. https://kclpure.kcl.ac.uk/portal/en/theses/the-role-of-liquid-chromatographyhigh-resolution-mass-spectrometry-in-the-diagnosis-and-treatment-of-substance-misuse(e155a5b7-6155-4416-9516-6ea54e048a3b).html.
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Substance misuse remains problematic with current concerns being the rise in acute poisoning deaths, particularly opioid-associated, and the ever-widening range of drugs available. Strategies for tackling opioid addiction and opioid related-deaths include researching alternative routes of therapeutic agent administration. Initial urine screening for substance misuse has traditionally employed immunoassays, with confirmation of specific analytes by chromatographic methods. Liquid chromatography-high resolution mass spectrometry (LC-HRMS) offers untargeted analysis without compromising selectivity, and enables users to ascertain putative elemental compositions of an analyte, retrospectively interrogate data, and to incorporate novel analytes easily. These features enable screening and confirmation of drugs in a single method, and may be advantageous for detecting novel psychoactive substances (NPS). This thesis aims to investigate the role of LC-HRMS in drug analysis in the clinical setting. A simple system was developed that is capable of detecting a wide range of commonly-encountered drugs and metabolites. Non-selective sample preparation was used to enable detection of as many compounds as possible, but significant matrix effects were observed. Additional information regarding selected NPS was ascertained through retrospective identification of mephedrone metabolites in patient urines, and through later incorporation of ethylphenidate, methylphenidate, and ritalinic acid, into the method. A separate quantitative LC-HRMS method was developed to facilitate pharmacokinetic studies of naloxone and naltrexone administered through alternative routes. The method was also applied to urine samples, with naloxone-3-glucuronide identified as a potential marker to differentiate between Subutex and Suboxone use. LC-HRMS has advantages in drug detection, particularly in regard to NPS, and in method development. However, application in the clinical setting is restricted by requirements for high throughput, timely results, and operation to accepted ‘cutoff’ values that introduce awkward compromises in system operation. LC-HRMS may have greater application in the forensic setting where more time is available for the analysis of a single sample.
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Fivga, Antzela. "Comparison of the effect of pre-treatment and catalysts on liquid quality from fast pyrolysis of biomass." Thesis, Aston University, 2012. http://publications.aston.ac.uk/16524/.
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The overall objective of this work was to compare the effect of pre-treatment and catalysts on the quality of liquid products from fast pyrolysis of biomass. This study investigated the upgrading of bio-oil in terms of its quality as a bio-fuel and/or source of chemicals. Bio-oil used directly as a biofuel for heat or power needs to be improved particularly in terms of temperature sensitivity, oxygen content, chemical instability, solid content, and heating values. Chemicals produced from bio-oil need to be able to meet product specifications for market acceptability. There were two main objectives in this research. The first was to examine the influence of pre-treatment of biomass on the fast pyrolysis process and liquid quality. The relationship between the method of pre-treatment of biomass feedstock to fast pyrolysis oil quality was studied. The thermal decomposition behaviour of untreated and pretreated feedstocks was studied by using a TGA (thermogravimetric analysis) and a Py-GC/MS (pyroprobe-gas chromatography/mass spectrometry). Laboratory scale reactors (100g/h, 300g/h, 1kg/h) were used to process untreated and pretreated feedstocks by fast pyrolysis. The second objective was to study the influence of numerous catalysts on fast pyrolysis liquids from wheat straw. The first step applied analytical pyrolysis (Py-GC/MS) to determine which catalysts had an effect on fast pyrolysis liquid, in order to select catalysts for further laboratory fast pyrolysis. The effect of activation, temperature, and biomass pre-treatment on catalysts were also investigated. Laboratory experiments were also conducted using the existing 300g/h fluidised bed reactor system with a secondary catalytic fixed bed reactor. The screening of catalysts showed that CoMo was a highly active catalyst, which particularly reduced the higher molecular weight products of fast pyrolysis. From these screening tests, CoMo catalyst was selected for larger scale laboratory experiments. With reference to the effect of pre-treatment work on fast pyrolysis process, a significant effect occurred on the thermal decomposition of biomass, as well as the pyrolysis products composition, and the proportion of key components in bio-oil. Torrefaction proved to have a mild influence on pyrolysis products, when compared to aquathermolysis and steam pre-treatment.
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Troya, Maria Rosa. "Improving liquid chemical intervention methods to control pathogens on fresh-cut fruits and vegetables." Texas A&M University, 2003. http://hdl.handle.net/1969.1/3929.
Full textAbstract:
Factors that affect liquid chemical intervention methods of controlling pathogens
on fresh-cut produce were investigated. The relationship between produce tissue
structure (intercellular space, cell size, and cell distribution) and the sanitizing
effectiveness of liquid chemical treatment was studied. Experiments determined if
sanitizer contact with bacteria could be improved through the use of surfactants and
different application methods (drop application method, negative pressure differential,
and sonication). To test these factors, a model sanitizer, H2O2, and a model
microorganism: Salmonella Typhimurium, along with various fresh-cut produce (apple,
pear, carrot, and potato) were tested. Microscopic analysis revealed a very complicated
pore structure consisting of irregular capillaries. S. Typhimurium was found to survive in
all produce tested, and washing did not significantly reduced inoculated bacteria
regardless of the bacterial incubation time or produce type. The results showed that a 3%
H2O2 solution reduced S. Typhimurium in produce and the solutionÂs efficiency varied in
the following descending order: potato>apple>carrot>pear. In seven min treatments,
bacteria were reduced by 2.5 CFU/ml in potato, 2.3 CFU/ml in apple, 1.5 CFU/ml in
carrot, and 0.7 CFU/ml in pear. There was no direct evidence on how intercellular space,
its percentage or cellular distribution and shape affected efficiency, but some possibilites
were discussed. The rate and extent of liquid penetration, and how varying pore
diameter in each cell or air space prevent complete chemical treatment penetration were
also analyzed.
It was determined that bacterial density has a slight effect in bacterial reduction
but this depends on type of produce inoculated. The use of surfactants did not improve
bacterial reduction in either washing or chemical treatments, and neither did the use of drop application method or temperature differential. On the other hand, applying the
chemical treatment with a surfactant while using a sonicator did improve the treatmentÂs
efficiency. This thesis provides a number of factors to be considered when designing a
chemical treatment and a guideline for further research in areas such as rate and extent of
liquid chemical treatment penetration into fresh-cut produce.
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Derdar, Mawaheb M. Zarok. "Experimental and kinetic modelling of multicomponent gas/liquid ozone reactions in aqueous phase. Experimental investigation and Matlab modelling of the ozone mass transfer and multicomponent chemical reactions in a well agitatated semi-batch gas/liquid reactor." Thesis, University of Bradford, 2010. http://hdl.handle.net/10454/4872.
Full textAbstract:
Due to the ever increasing concerns about pollutants and contaminants found in water, new treatment technologies have been developed. Ozonation is one of such technologies. It has been widely applied in the treatment of pollutants in water and wastewater treatment processes. Ozone has many applications such as oxidation of organic components, mineral matter, inactivation of viruses, cysts, bacteria, removal of trace pollutants like pesticides and solvents, and removal of tastes and odours. Ozone is the strongest conventional oxidant that can result in complete mineralisation of the organic pollutants to carbon dioxide and water. Because ozone is unstable, it is generally produced onsite in gas mixtures and is immediately introduced to water using gas/liquid type reactors (e.g. bubble columns). The ozone reactions are hence of the type gas liquid reactions, which are complex to model since they involve both chemical reactions, which occur in the liquid phase, and mass transfer from the gas to the liquid phase. This study focuses on two aspects: mass transfer and chemical reactions in multicomponent systems. The mass transfer parameters were determined by experiments under different conditions and the chemical reactions were studied using single component and multicomponent systems. Two models obtained from the literature were adapted to the systems used in this study.
Mass transfer parameters in the semi-batch reactor were determined using oxygen and ozone at different flow rates in the presence and absence of t-butanol. t-Butanol is used as a radical scavenger in ozonation studies and it has been found to affect the gas¿liquid mass transfer rates. An experimental study was carried out to investigate the effects of t-butanol concentrations on the physical properties of aqueous solutions, including surface tension and viscosity. It was found that t-butanol reduced both properties by 4% for surface tension and by a surprising 30% for viscosity. These reductions in the solution physical properties were correlated to enhancement in the mass transfer coefficient, kL. The mass transfer coefficient increased by about 60% for oxygen and by almost 50% for ozone. The hydrodynamic behaviour of the system used in this work was characterised by a homogeneous bubbling regime. It was also found that the gas holdup was significantly enhanced by the addition of t-butanol. Moreover, the addition of t-butanol was found to significantly reduce the size of gas bubbles, leading to enhancement in the volumetric mass transfer coefficient, kLa.
The multicomponent ozonation was studied with two systems, slow reactions when alcohols were used and fast reactions when endocrine disrupting compounds were used.
ii
These experiments were simulated by mathematical models. The alcohols were selected depending on their volatilization at different initial concentrations and different gas flow rates. The degradation of n-propanol as a single compound was studied at the lowest flow rate of 200 mL/min. It was found that the degradation of n-propanol reached almost 60% within 4 hours. The degradation of the mixture was enhanced with an increase in the number of components in the mixture. It was found that the degradation of the mixture as three compounds reached almost 80% within four hours while the mixture as two compounds reached almost 70%. The effect of pH was studied and it was found that an increase in pH showed slight increase in the reaction. Fast reactions were also investigated by reacting endocrine disrupting chemicals with ozone. The ozone reactions with the endocrine disrupters were studied at different gas flow rates, initial concentrations, ozone concentrations and pH. The degradation of 17¿-estradiol (E2) as a single compound was the fastest, reaching about 90% removal in almost 5 minutes. However estrone (E1) degradation was the lowest reaching about 70% removal at the same time. The degradation of mixtures of the endocrine disruptors was found to proceed to lower percentages than individual components under the same conditions. During the multicomponent ozonation of the endocrine disruptors, it was found that 17¿-estradiol (E2) converted to estrone (E1) at the beginning of the reaction.
A MATLAB code was developed to predict the ozone water reactions for single component and multicomponent systems. Two models were used to simulate the experimental results for single component and multicomponent systems. In the case of single component system, good simulation of both reactions (slow and fast) by model 1 was obtained. However, model 2 gave good agreement with experimental results only in the case of fast reactions. In addition, model 1 was applied for multicomponent reactions (both cases of slow and fast reaction). In the multicomponent reactions by model 1, good agreement with the experimental results was also obtained for both cases of slow and fast reactions.Ministry of Higher Education in Libya and the Libyan Cultural Centre and Educational Bureau in London.
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Huber, Sebastian. "Small-scale biogas production from organic waste and application in mid-income countries – a case study of a Lebanese community." Thesis, Uppsala universitet, Institutionen för geovetenskaper, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-385775.
Full textAbstract:
The controlled anaerobic digestion of organic waste in a biogas facility aggregates advantages of waste treatment, energy recovery and nutrient recycling and is a promising technology to deal with contemporary issues of waste management and energy recovery. Small-scale biogas production units can be simply designed and successfully operated even in settings where means for advanced technology equipment are low and institutional capacities limited. In the country of Lebanon, landfilling and open dumping of solid waste is common practice and anaerobic treatment of waste is applied only sporadically and hence, not well-established. The aim of this study was to assess the feasibility of small-scale biogas production using organic waste, explore options for its application and propose a business model on how feedstock sourcing, facility operation and end product utilization could be realized in the research area. Research area was Ghazir village, a community within the urbanized coastal area in Lebanon. Methods were of both quantitative and qualitative nature.A techno-economic assessment served to quantify biogas and liquid digestate production rates, based on available resources of organic waste in the research area. Costs associated with installation, operation and maintenance of the proposed facility have been projected based on present examples of similar facilities in the country. Interviews with local stakeholders and a questionnaire survey among residents in the area of research allowed to identify suitable end use options for the produced biogas and served to explore communal acceptance of local biogas production. Results show that the produced biogas can be used for thermal feedstock treatment to supply local farmers with a fertilizer alternative, i.e. the liquid digestate. Organic waste that is subject to the anaerobic treatment in a digester can be provided by multiple point sources, i.e. households and a local food market in the form of source-sorted kitchen waste and unsold fruits and vegetables, respectively. Due to the current unfamiliarity with anaerobic treatment of organic waste in the research area, tests on the effects on crop yields are advised to take place before implementation of the proposed business model, as its communal benefits hinge on the suitability of the liquid digestate as a fertilizer. Economic calculations show low investment costs for the proposed facility as well as acceptable annual revenues in case the liquid digestate proves to be of interest for commercial acquisition by local farmers. The used methods and strategies in this feasibility assessment, i.e. waste quantification, yield and cost calculations, stakeholder interviews and questionnaire survey allow for replication of the taken investigation to eventually initiate small-scale biogas production using organic waste in other settings with similar conditions.
34
Derdar, Mawaheb M. Zarok. "Experimental and kinetic modelling of multicomponent gas/liquid ozone reactions in aqueous phase : experimental investigation and Matlab modelling of the ozone mass transfer and multicomponent chemical reactions in a well agitated semi-batch gas/liquid reactor." Thesis, University of Bradford, 2010. http://hdl.handle.net/10454/4872.
Full textAbstract:
Due to the ever increasing concerns about pollutants and contaminants found in water, new treatment technologies have been developed. Ozonation is one of such technologies. It has been widely applied in the treatment of pollutants in water and wastewater treatment processes. Ozone has many applications such as oxidation of organic components, mineral matter, inactivation of viruses, cysts, bacteria, removal of trace pollutants like pesticides and solvents, and removal of tastes and odours. Ozone is the strongest conventional oxidant that can result in complete mineralisation of the organic pollutants to carbon dioxide and water. Because ozone is unstable, it is generally produced onsite in gas mixtures and is immediately introduced to water using gas/liquid type reactors (e.g. bubble columns). The ozone reactions are hence of the type gas liquid reactions, which are complex to model since they involve both chemical reactions, which occur in the liquid phase, and mass transfer from the gas to the liquid phase. This study focuses on two aspects: mass transfer and chemical reactions in multicomponent systems. The mass transfer parameters were determined by experiments under different conditions and the chemical reactions were studied using single component and multicomponent systems. Two models obtained from the literature were adapted to the systems used in this study. Mass transfer parameters in the semi-batch reactor were determined using oxygen and ozone at different flow rates in the presence and absence of t-butanol. t-Butanol is used as a radical scavenger in ozonation studies and it has been found to affect the gas-liquid mass transfer rates. An experimental study was carried out to investigate the effects of t-butanol concentrations on the physical properties of aqueous solutions, including surface tension and viscosity. It was found that t-butanol reduced both properties by 4% for surface tension and by a surprising 30% for viscosity. These reductions in the solution physical properties were correlated to enhancement in the mass transfer coefficient, kL. The mass transfer coefficient increased by about 60% for oxygen and by almost 50% for ozone. The hydrodynamic behaviour of the system used in this work was characterised by a homogeneous bubbling regime. It was also found that the gas holdup was significantly enhanced by the addition of t-butanol. Moreover, the addition of t-butanol was found to significantly reduce the size of gas bubbles, leading to enhancement in the volumetric mass transfer coefficient, kLa. The multicomponent ozonation was studied with two systems, slow reactions when alcohols were used and fast reactions when endocrine disrupting compounds were used. ii These experiments were simulated by mathematical models. The alcohols were selected depending on their volatilization at different initial concentrations and different gas flow rates. The degradation of n-propanol as a single compound was studied at the lowest flow rate of 200 mL/min. It was found that the degradation of n-propanol reached almost 60% within 4 hours. The degradation of the mixture was enhanced with an increase in the number of components in the mixture. It was found that the degradation of the mixture as three compounds reached almost 80% within four hours while the mixture as two compounds reached almost 70%. The effect of pH was studied and it was found that an increase in pH showed slight increase in the reaction. Fast reactions were also investigated by reacting endocrine disrupting chemicals with ozone. The ozone reactions with the endocrine disrupters were studied at different gas flow rates, initial concentrations, ozone concentrations and pH. The degradation of 17β-estradiol (E2) as a single compound was the fastest, reaching about 90% removal in almost 5 minutes. However estrone (E1) degradation was the lowest reaching about 70% removal at the same time. The degradation of mixtures of the endocrine disruptors was found to proceed to lower percentages than individual components under the same conditions. During the multicomponent ozonation of the endocrine disruptors, it was found that 17β-estradiol (E2) converted to estrone (E1) at the beginning of the reaction. A MATLAB code was developed to predict the ozone water reactions for single component and multicomponent systems. Two models were used to simulate the experimental results for single component and multicomponent systems. In the case of single component system, good simulation of both reactions (slow and fast) by model 1 was obtained. However, model 2 gave good agreement with experimental results only in the case of fast reactions. In addition, model 1 was applied for multicomponent reactions (both cases of slow and fast reaction). In the multicomponent reactions by model 1, good agreement with the experimental results was also obtained for both cases of slow and fast reactions.
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Mfa-Mezui, Antoine Aime. "The effect of ultraviolet-C treatment on the biochemical composition of beer." Thesis, Stellenbosch : Stellenbosch University, 2012. http://hdl.handle.net/10019.1/20365.
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Thesis (PhD)--Stellenbosch University, 2012.ENGLISH ABSTRACT: This study describes: · Development of analytical tools to investigate the light struck flavour (LSF) in beer by Gas chromatography mass spectrometry (GCMS) and by liquid chromatography mass spectrometry/mass spectrometry (LCMS/MS). Development of a high performance liquid chromatography (HPLC) method to analyse carbohydrates in beer. · The efficiency a pilot scale ultraviolet (UV-C) system at 254 nm to inactivate spoilage microorganisms spiked in commercial beer. Bacteria test were Lactobacillus brevis, Acetobacter pasteurianus and Saccharomyces cerevisiae · A pilot scale UV treatment of commercial and non-commercial lager beers at UV dosage of 1000 J/L. Following the UV treatment, the correlation between chemical analyses and sensory tests conducted by consumers’ tasters were investigated. · A pilot scale UV treatment of non-commercial beer brewed with reduced hops iso-α-acids (tetrahydro-iso-α-acids) at UV dosage of 1000 J/L. Sensory changes and chemical properties were investigated. · The development and optimisation of an UV light emitting diodes (UV-LED) bench scale apparatus. Chemical and microbiological tests were conducted to investigate the effect of UV-LEDs on beer at 250 nm and 275 nm wavelengths.
AFRIKAANSE OPSOMMING: Hierdie studie beskryf: · Die ontwikkeling van analitiese toerusting om die invloed van lig op die smaakontwikkeling in bier te bestudeer m.b.v gaschromatografie massa spektrometrie (GCMS) en vloeistofchromatografie massa spektrometrie/massa spektrometrie, asook die ontwikkeling van ‘n hoë druk vloeistofchromatografiese metode vir die analise van koolhidrate in bier. · Die doeltreffendheid van ‘n toetsskaal ultraviolet (UV-C) sisteem om die nadelige mikroorganismes waarmee die bier geïnnokuleer was, by 254 nm te inaktiveer.. Toetse is uitgevoer met die volgende bakterieë, Lactobacillus brevis, Acetobacter pasteuriants en Saccharomyces cerevisiae. · ‘n Toetsskaal UV behandeling van kommersiële en nie-kommersiële lager biere by ‘n UV dosering van 1000 J/L. Na UV behandeling is die verwantskap tussen chemiese analises en ‘n reeks sensoriese toetse deur vebruikers proeërs ondersoek.. · ‘n Toetsskaal UV behandeling van ‘n nie-kommersiële bier gebrou met verlaagde hops-iso-α-sure (tetrahidro-iso-α -sure) by UV dosering van 1000 J/L. Sensoriese veranderinge asook chemiese eienskappe is ondersoek. · Die ontwikkeling en optimalisering van ‘n UV-lig emissie diodes bankskaal apparaat. Chemiese en mikrobiologiese toetse is uitgevoer om die effek van UV lig op bier by 250 nm en 275 nm te ondersoek.
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Signe, Mamba Stéphanie. "The dynamics of liquid plugs in synthetic networks under cyclic forcings : towards understanding and treatment of respiratory diseases." Thesis, Lille 1, 2018. http://www.theses.fr/2018LIL1I005/document.
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Le système respiratoire est très complexe de par sa structure fractale qui induit des physiques très différentes. Les bouchons liquides caractéristiques de certaines maladies comme la mucoviscidose, les bronchites chroniques ou l’asthme résultent de l’accumulation de mucus dans les voies pulmonaires. Comprendre les mécanismes à l’œuvre lors de l’écoulement de ces bouchons lors d’un cycle respiratoire est donc primordial pour améliorer notre compréhension et le traitement de ces pathologies. Nous présentons dans cette thèse une première étude théorique et expérimentale de la dynamique de ces bouchons liquides dans des tubes capillaires rigides soumis à des forçages unidirectionnels et cycliques. Nous avons développé au cours de ce travail un modèle simplifié permettant de reproduire quantitativement les dynamiques observées, de comprendre la physique sous-jacente et d’identifier les sources d’instabilités qui entraînent la rupture d’un pont liquide. Ce modèle nous a permis de déterminer les pressions critiques nécessaires à la réouverture des voies pulmonaires. Ensuite, nous nous sommes intéressés à la dynamique des ponts liquides dans des tubes rectangulaires. Nous avons identifié de nouveaux régimes qui n’apparaissent pas dans les géométries cylindriques, et en particulier un régime d’oscillation stable sous forçage en pression périodique. Enfin nous nous sommes intéressés à la dynamique cyclique de ponts liquides dans des réseaux synthétiques en arbres. Nos premiers résultats montrent que les ponts qui ne sont pas détruits lors du premier demi-cycle persistent très longtemps dans les voies et oscillent de manière cyclique dans une génération jusqu’à leur ruptureOwing to the complexity of the respiratory system, the mechanism of breathing is not well understood, especially in pathological conditions when airways are obstructed by mucus. The presence of liquid plugs resulting from the accumulation of mucus in the bronchial tree is a characteristic of genetic diseases like cystic fibrosis or chronic diseases like asthma or chronic bronchitis. Thus, understanding the dynamics of these plugs during the breathing cycle is essential to improve our understanding of those diseases. In this thesis, we study experimentally and theoretically, the dynamics and rupture of liquidplugs under unidirectional and cyclic forcing in a rigid capillary tube. We develop a reduced dimension model, which quantitatively reproduces the observed dynamics, unveil the underlying physics and in particular the sources of the plug instability leading to its rupture. From this model, we are able to derive the critical pressure magnitude required to reopen obstructed pathways. Then we investigated the cyclic dynamics of liquid plugs in rectangular channels, a geometry of the utmost interest for microfluidic systems. In this case, we show that under cyclic pressure forcing, two regimes can be observed depending on the values of the capillary number: one leading to the rupture of the plug and one to stable cyclic oscillations.Finally, in the last part of this work, we study experimentally the cyclic forcing of liquid plugs in tree structures mimicking the geometry of intermediate generation of the lung. These preliminary results show that plugs not ruptured during the first half cycle persist in the airways for a long time and oscillate until their rupture
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Gunes, Kaan. "In-situ Ultrasonic Compatibilization of Binary Blends of Flexible Chain Polyesters and Aromatic Liquid Crystalline Polymers." University of Akron / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=akron1252611659.
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Wu, Shimin, and Shimin Wu. "Fate of Glucocorticoid Receptor Agonists During Water and Wastewater Treatment Processes." Diss., The University of Arizona, 2016. http://hdl.handle.net/10150/623167.
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In recent years, endocrine disruption of corticosteroid signaling pathways in wildlife and humans by environmental chemicals have attracted increasing attention. The integrated potential of chemicals in the aquatic environment that disrupt corticosteroid actions have been evaluated using in vitro glucocorticoid receptor (GR) mediated bioassays. Exogenous natural and synthetic corticosteroids (CSs), which are widely used in human and animal therapeutic applications, were demonstrated to be the most important GR agonists, that can potentially cause adverse effects, especially on aquatic organisms. To date, only a few studies have investigated the occurrence and behavior of GR agonists in the aquatic environment and their removal in conventional wastewater treatment plants. Furthermore, there are hardly any data reported on the removal of GR agonists by advanced water and wastewater treatment, especially those synthetic CSs with high potency. To further understand the fate of GR agonists in water and wastewater treatment processes, a sensitive and robust LC-MS/MS method was successfully developed for analyzing a wide range of GR agonists in various environmental waters. The occurrence of GR agonists in surface water and groundwater was monitored along the Lower Santa Cruz River (SCR). Several GR agonists were detected, and a trend of degradation was observed downstream the two WWTP outfalls for both surface water and groundwater. The fate of GR agonists in a local wastewater treatment plant (WWTP) was investigated, and up to 14 GR agonists were detected at different stages. Highly potent synthetic CSs, including clobetasol propionate (CBP), fluticasone propionate (FTP), fluocinolone acetonide (FCA), and triamcinolone acetonide (TCA), were poorly removed in WWTP. Negative removal of some CSs was observed in primary treatment, which may due to the deconjugation of CS conjugates. Removal of GR agonists in secondary effluent during various advanced water treatment processes, including UV, ozonation, MF, RO and chlorination, were studied. UV and RO appeared to be the most efficient treatment process for the attenuation of GR agonists, followed by ozone, while chlorination had little effects on GR agonists in water. Bench-scale experiments were then carried out to investigate the removal of GR agonists by ultraviolet based advanced oxidation processes (UV/AOPs), and powder activated carbon (PAC). UV/chlorine and UV/H2O2 were demonstrated to be effective in removal GR agonists in wastewater, and UV photolysis would be the predominant mechanism in UV/AOP processes. Four types of PACs were tested for removing GR agonists in wastewater effluent, and Cabot HDB carbon was suggested, while Calgon PWA carbon was not recommended due to its low removal efficiency.
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Bi, Tianzhu. "Biological Treatment of Milk and Soybean Wastewater with Bioproducts." Cleveland State University / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=csu1292017443.
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Kang, Young Jo. "Some aspects of non-metallic inclusions during vacuum degassing in ladle treatment : with emphasize on liquid CaO-Al2O3 inclusions." Doctoral thesis, Stockholm : Department of Materials Science and Engineering, (Materialvetenskap), 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4288.
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Torán, María Josefina. "Continuous wastewater treatment by trametes versicolor immobilized on lignocellulosic support." Doctoral thesis, Universitat Autònoma de Barcelona, 2018. http://hdl.handle.net/10803/663899.
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En el darrer segle, la contaminació de l'aigua s'ha convertit en un problema important que afecta a una gran part de la població i al medi ambient. La contaminació es deu principalment a les descàrregues d'aigües residuals no tractats o tractats inadequadament. Les plantes de tractament d'aigües residuals convencionals solen eliminar els compostos orgànics, però no estan dissenyades per eliminar altres contaminants com els microcontaminants, de manera que aquests es podem descarregar directament al medi ambient juntament amb el efluents.
Entre els possibles tractaments, els fongs de podridura blanca s'han convertit en una tecnologia prometedora per al tractament d'aigües residuals, ja que poden eliminar una àmplia gamma de contaminants complexos a causa del seu sistema enzimàtic ligninolític inespecífic. S'han estudiat els fongs de podridura blanca per a l'eliminació de diferents microcontaminants en aigües residuals, però el creixement de microorganismes natius de les aigües residuals ha fet que l'operació en continu en reactor duri poc temps degut a la disminució en les eficiències d'eliminació.
Com alternativa a aquest problema, la present tesi proposa l'aplicació d'un bioreactor utilitzant el fong de podridura blanca T. versicolor immobilitzat sobre un suport lignocel·lulòsic per resoldre aquest problema i permetre així el tractament en continu de les aigües residuals durant llargs períodes de temps.
En primer lloc, es va realitzar una selecció del substrat amb l'objectiu de seleccionar el millor material lignocel·lulòsic per al creixement fúngic i la fusta de palets es va seleccionar per als següents experiments. Es van realitzar estudis d'immobilització en un bioreactor de llit fluïditzat. Es van obtenir bons resultats amb pellets formats amb un cor de fusta, però el procés resultant no es escalable, per això es van proposar nous sistemes.
Es va desenvolupar i operar un bioreactor de filtre percolador i un bioreactor de llit fix. Ambdós van operar en continu durant llargs períodes de temps amb T. versicolor immobilitzats sobre fusta de pallets i van ser emprats per al tractament d'aigües residuals procedents de diferents fonts: aigües residuals hospitalàries amb compostos farmacèutics actius, aigües residuals industrials de processament d'aliments amb àcids húmics i aigües residuals de zones rurals amb plaguicides. L'optimització de les condicions operatives és un tema clau per millorar el rendiment del reactor. Al bioreactor de filtre percolador, es van optimitzar la relació de recirculació i el volum total. D'altra banda, en el bioreactor del llit fix es van realitzar estudis preliminars de pH, biomassa fúngica, sorció sobre la fusta i aeració.En el último siglo, la contaminación del agua se ha convertido en un problema importante que afecta a una gran parte de la población y al medio ambiente. La contaminación se debe principalmente a las descargas de aguas residuales no tratadas o tratadas inadecuadamente en cuerpos de agua. Las plantas convencionales de tratamiento de aguas residuales generalmente eliminan los compuestos orgánicos, pero no están diseñadas para la eliminación de otros contaminantes como los microcontaminantes, por lo que estos pueden ser descargados junto con los efluentes directamente al medio ambiente. Entre las posibles tecnologías para el tratamiento de aguas residuales, los hongos de podredumbre blanca se han convertido en una alternativa prometedora porque pueden eliminar una amplia variedad de microcontaminantes debido a que presentan un sistema enzimático ligninolítico inespecífico. Los hongos de podredumbre blanca se han estudiado para la eliminación de una amplia gama de microcontaminantes en aguas residuales, pero el crecimiento excesivo de bacterias nativas del agua residual por lo general produce una disminución en las eficiencias de eliminación acortando la operación en continuo de los biorreactores. Como alternativa a este problema, la presente tesis propone la aplicación de un biorreactor utilizando el hongo de podredumbre blanca T. versicolor inmovilizado sobre un soporte lignocelulósico. Esta estrategia permitiría el tratamiento en continuo de aguas residuales durante largos periodos de operación. En primer lugar, se realizó un estudio con el objetivo de seleccionar el material lignocelulósico óptimo para el crecimiento de T. versicolor eligiéndose la madera de palé para los siguientes experimentos. Los posteriores estudios de inmovilización se realizaron en un biorreactor de lecho fluidizado. Se obtuvieron buenos resultados con el hongo auto-immobilizado sobre madera formado un pellet, pero el proceso no resultó escalable por lo cual se propusieron nuevos sistemas alternativos. Se desarrolló y operó un biorreactor de filtro percolador y un biorreactor de lecho fijo utilizando T. versicolor inmovilizado sobre madera de palé para el tratamiento en continuo de aguas residuales durante largos periodos de operación. Ambos reactores se emplearon para el tratamiento de aguas residuales de diferentes orígenes: aguas residuales hospitalarias con compuestos farmacéuticos activos, aguas residuales industriales de procesadoras de alimentos con ácidos húmicos y aguas residuales de áreas rurales con pesticidas. La optimización de las condiciones operacionales resulta una cuestión clave para mejorar el rendimiento de los reactores. Por un lado, en el biorreactor de filtro percolador, se optimizaron la relación de recirculación y el volumen total de trabajo. Por otro lado, en el biorreactor de lecho fijo se realizaron estudios preliminares de pH, cantidad de biomasa, sorción en la madera y aireación. En conclusión, ambos sistemas con T. versicolor inmovilizados sobre madera de palé resultaron ser una buena alternativa para el tratamiento en continuo de diferentes aguas residuales durante largos periodos de tiempo. El biorreactor de filtro percolador logró eliminar el 61% de los compuestos activos farmacéuticos presentes en aguas residuales hospitalarias durante 85 días; el 50% de eliminación de ácido húmico presentes en aguas residuales industriales durante 26 días; y la eliminación del 84% de diuron durante 18 días utilizando agua sintética. En el biorreactor de lecho fijo se obtuvo más del 90% de eliminación de diuron durante 50 días operando con agua real de origen rural.
Over the last century, the water pollution has become a major problem which affects a large part of population and the environment. It is originated principally due to the discharges of untreated or inadequately treated wastewater in water bodies. Conventional wastewater treatment plants (WTTPs) typically remove organic compounds, but they are not designed to remove other pollutants such as micropollutants, so they can be discharged into the environment together with the effluents from the WTTPs. Among the possible treatments, white-rot fungi (WRF) have become a promising alternative for the wastewater treatment because it can remove a wide range of micropollutants due to their nonspecific ligninolytic enzymatic system. WRF have been studied for the removal of a wide range of micropollutants in real wastewater, but the bacteria overgrowth usually produced a decline in removal efficiencies and consequently short-term operations are obtained. The present thesis proposes the application of a bioreactor system using the WRF Tramentes versicolor immobilized on a lignocellulosic support, to solve this problem and to allow the continuous long-term wastewater treatment. First of all, a substrate screening was performed in order to select the best lignocellulosic material for fungal growth. The pallet wood was selected for the following experiments. Immobilization studies were performed in a fluidized bed bioreactor. Good results were obtained with complex wood pellets, but the process results not scalable, hence new systems were proposed. A trickle-bed bioreactor and a packed-bed bioreactor were developed and operated in a continuous long-term treatment with T. versicolor immobilized on pallet wood. Both reactors were employed for the treatment of wastewater from different sources: hospital wastewater with pharmaceutical active compounds, food-processing industrial wastewater with humic acids and rural area wastewater with pesticides. The optimization of operational conditions is a key issue to improve the reactor performance. In the trickle-bed bioreactor, the recycling ration and the total volume were optimized. Meanwhile, in the packed-bed bioreactor preliminary studies of pH, fungal biomass, wood sorption and aeration were carried out. In conclusion, both bioreactors systems with T. versicolor immobilized on pallet wood are a good alternative for the continuous long-term treatment of different wastewaters. The trickle-bed bioreactor achieved 61% of PhACs removal from hospital wastewater during 85 days; 50% humic acid removal from industrial wastewater for 26 days; and 84% diuron removal from synthetic tap water during 18 days. In the packed-bed bioreactor treating real wastewater, more than 90% removal of diuron was obtained during 50 days
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Yavuz, Merve. "Investigation Of Occurrence And Fate Of Biocides In Wastewater Treatment Plants And Surface Waters." Master's thesis, METU, 2013. http://etd.lib.metu.edu.tr/upload/12615634/index.pdf.
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Biocides are widely used as a preservative or as an antiseptic agent in consumer care products such as
toothpaste, mouthwash, and soaps, as well as in household cleaners and even in textiles due to their
high antimicrobial effectiveness. The usage of this compounds results in discharge to wastewater
treatment plants and so into surface waters.
Their existence in the environment is of importance due to their negative effects on aquatic
environment microorganisms and human health in terms of occurrence in surface waters and their fate
in wastewater treatment plants.
In this scope, this study focuses on occurrence and fate of selected biocides, namely triclosan (TCS)
and chlorhexidine (CHD), in wastewater treatment plants and in surface waters. It was aimed to
determine the biocides levels in surface water and wastewater in Turkey. For the wastewater treatment
plant (WWTP) studies, several WWTPs with different process configurations, namely, Tatlar WWTP,
METU WWTP, Kayseri WWTP and Antalya WWTPs were selected. Composite wastewater samples
were taken from various points along the WWTPs on a seasonally basis for one year period. For the
surface water part, samples were taken monthly from three different sources with different pollution
levels, namely, Kesikköprü
Reservoir, Ç
amlidere Reservoir and Eymir Lake for one year period. All water samples were analyzed for their biocide level using liquid chromatography, following solid phase cartridge extraction. As a result of analyses, TCS concentration in surface water samples was detected as in the range of 0.65-11.15 ng/L, 0.86-48.96 ng/L and 0.86-757.7 ng/L for clean, moderately polluted and polluted water sources respectively. The recovery of solid phase extraction analyses for TCS was achieved as %92. CHD concentration was determined as in the range of <
1.33-5.31 ng/L for surface water samples and the recovery of extraction were calculated as %96 for CHD. The concentration of TCS in wastewater samples was measured as in the range of 1.77-94.47 ng/L and 1.40-15.09 ng/L for influent and effluent samples respectively. These ranges became 1.39-10.45 ng/L and <
1.32-2.44 ng/L for CHD. The highest concentrations of biocides were observed in sludge samples with concentrations of 1117-3687 &mu
g/kg and 510-2742 &mu
g/kg for TCS and CHD. Biocide removal efficiency of primary and biological treatment together was reported as % 67.5±
8.2 in January 2012 Tatlar WWTP analyses.
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Marcelli, Giacomo. "Development of a plasma gun device with multijet array for treatment of liquids." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2018.
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The aim of the present work is the development of a non-equilibrium atmospheric pressure plasma multijet device for the treatment of liquids. The interest in plasma multijet device is due to the potentiality for scaling up of plasma jet applications, since such device allows for treatment of higher volume of liquid than single-jet system. The multijet device has been developed in the laboratories of GREMI (Groupe de Recherches sur l’Energétique des Milieux Ionisés) at Orléans, and afterward tested for liquid decontamination in the “Tesla Plasma Research lab” laboratories of the group for Industrial Applications of Plasmas at the Alma Mater Studiorum - Università di Bologna. A versatile multijet device, able to work both in ambient air with jets impinging on a liquid target or in underliquid condition, with plasma discharge formation in bubbles flushed inside the liquid has been realized. Different liquids have been exposed to the plasma investigating the change in pH value, conductivity, temperature and reactive species concentration induced in liquid after plasma treatment. Afterward, electrical characterization has been performed by means of voltage and current probes in order to evaluate the power consumption. Finally, decontamination activity of the plasma treatment has been investigated using a liquid solution inoculated with Escherichia coli revealing antibacterial efficacy.
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Yan, Xueru. "Development of a hybrid process, Membrane-Ionic Liquid (ILM), for gas treatment Ionic liquids combined wtih membrane separation processes : A review." Thesis, Ecole centrale de Marseille, 2020. http://www.theses.fr/2020ECDM0009.
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L'élimination des polluants d'un mélange gazeux est un enjeu majeur en termes de réduction de l'impact environnemental de nombreux procédés industriels. Les liquides ioniques sont des solvants de remplacement prometteurs pour les composés organiques traditionnels utilisés dans la séparation sélective en raison de leur pression de vapeur négligeable et de leurs propriétés chimico-physiques concevables. Dans cette étude, un nouveau concept, la combinaison des IL et d'une membrane céramique tubulaire (ILM), a été développé dans le but de séparer les gaz ou les liquides des flux d'alimentation. Par rapport aux procédés classiques d'élimination des gaz ou des liquides, les ILM offrent une grande stabilité et une résistance mécanique élevée pendant une longue période de fonctionnement. Dans le cas des traitements de gaz, l'élimination de l'humidité pour protéger le capteur de gaz et le traitement du gaz industriel contenant du toluène sont les deux parties développées dans ce manuscrit. Les effets de plusieurs paramètres de fonctionnement, notamment le débit de gaz, la température, la pression, la concentration d'alimentation, la surface effective de la membrane (longueur de la membrane de support) et la position des canaux de gaz, ont été étudiés à la fois sur l'élimination de l'humidité et du toluène (vapeur). En outre, un modèle mathématique en deux étapes a été utilisé pour simuler les résultats expérimentaux et évaluer la performance de séparation des MIL dans les conditions de fonctionnement proposées. Selon les résultats expérimentaux et simulés, les ILM présentaient une capacité d'absorption relativement élevée de l'humidité et du toluène. Ce nouveau procédé ILM sera le procédé vert dominant pour la séparation des polluants gazeux ou liquidesThe removal of pollutants from a gas mixture is a major issue in terms of minimizing the environment impact of numerous industrial processes. Ionic liquids are promising alternative solvents for traditional organic compounds using in selective separation due to their negligible vapor pressure and designable chemic-physical properties. In this study, a new concept, combination of ILs and a tubular ceramic membrane (ILM), has been developed with the aim of gas or liquid separation from feed streams. Comparing to conventional gas or liquid removal processes, ILMs provide high stability and mechanical resistance during long-time operation. Moreover, specific properties of ILs ensure selectivity and absorption capacity of ILMs. In the case of gas treatments, removal of humidity to protect gas sensor and treatment of industrial gas containing toluene are the two parts developed in this manuscript. Effects of several operating parameters, including gas flow rate, temperature, pressure, feed concentration, effective surface area of membrane (length of the support membrane) and position of gas channels, were investigated both on humidity and toluene (vapor) removal. In addition, a two-step model was used to simulate experimental results and evaluate the separation performance of ILMs. According to both experimental and simulated results, ILMs exhibited relative high absorption capacity of humidity and toluene. This new ILM process will be the dominating green processes for gas or liquid pollutants separation
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Dhakal, Santosh. "Evaluation of Synergistic, Additive and Antagonistic Effects During Combined Pressure-thermal Treatment on Selected Liquid Food Constituents by Reaction Kinetic Approach." The Ohio State University, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=osu1479773874979893.
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Pereira, Catarina Luísa Cortes. "Application of ionic liquids and enzymes for the removal of proteinaceous layers from polychrome of works of art and evaluation of the cleaning effectiveness." Master's thesis, Faculdade de Ciências e Tecnologia, 2012. http://hdl.handle.net/10362/9062.
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Dissertação Apresentada na Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa para obtenção do grau de Mestre em Ciências da Conservação, especialização em PinturaA novel use of ionic liquids as alternative solvents for enzymes in cleaning treatments for the removal of proteinaceous materials from painted or gilded surfaces is presented. The ionic liquids are potentially green solvents to be applied in restoration treatments being also called designer solvents, because of their peculiar properties which can be adjusted by selecting different cationanion combinations. Two ionic liquids were selected: IL1)1-butyl-3-methylimidazolium tetrafluoroborate ([BMIM][BF4])and IL2) 1-ethyl-3-methylimidazolium ethylsulfate ([EMIM][EtSO4]). Formulations were prepared with these ionic liquids and two different proteases: one acid (pepsin) and one alkaline (from Aspergillus sojae). Additionally aqueous gel formulations were prepared with these enzymes for reference purpose. A third enzyme provided by the Bromatology Department at the Faculty of Pharmacy from the Porto University was tested only in gel formulation in order to assess its potential use in cleaning treatments. To understand the enzyme activity of these formulations and predict their ability as cleaning agents, analyses were performed with ultraviolet–visible (UV-Vis) spectroscopy and highperformance liquid chromatography (HPLC) prior cleaning; and with matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF-MS) after cleaning. These formulations were tested on mock-up samples prepared in accordance with documented and historical sources of artistic techniques of egg tempera and oil painting, and gilding. A non-invasive non-destructive multi-scale analytical protocol was carried out for cleaning effectiveness evaluation and surface characterization before and after treatment. Different surface analytical techniques were adopted to this purpose: stereomicroscopy (SM), optical microscopy (OM) with visible and fluorescence light, atomic force microscopy (AFM), scanning electron microscopy (SEM) and electron dispersive spectroscopy (EDS) and colorimetry (CIE L*a*b* system). The surface analytical protocol proved to be adequate, not only, for monitoring the cleaning process but also for complete characterization of the surface, before and after treatment, including information on the presence of residues and possible surface deterioration. It was also proved that the formulations of enzymes combined with ILs can be used successfully for the removal of proteinaceous material as alternatives to gel formulations. More studies should be conducted to determine the most suitable IL or group of ILs, the main concern should focus on improving aspects such as compatibility with other surface materials, and possible long-term effects of residues after cleaning.
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Laverty, Garry. "The antimicrobial and cytotoxic characterisation of novel antimicrobial peptides and ionic liquid for the treatment and prevention of medical device related infection." Thesis, Queen's University Belfast, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.534716.
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Alatarvas, T. (Tuomas). "Evolution of inclusion population in calcium treated ultra-high strength steels:novel applications of sample data treatment." Doctoral thesis, Oulun yliopisto, 2018. http://urn.fi/urn:isbn:9789526220987.
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Abstract Non-metallic inclusions are unavoidable particles in steel and are often detrimental to the steelmaking process and the mechanical properties of the steel. While it is not feasible to remove all inclusions, in the well-established calcium treatment of aluminium-killed steel, solid aluminium oxides are transformed into less harmful liquid calcium aluminates. The main objective of this work was to develop a new inclusion identification and classification method. The presented method offers valuable information on phases of the inclusions. This data is often buried within simple inclusion classification criteria. The method offers the best approximation of the phases in each inclusion detected with minimal time, if no time-consuming elemental map analyses are available. In this work, applications for the inclusion phase identification method are presented. Utilising the method, the dispersion and evolution of inclusions during the sampling of liquid steel in lollipop samples is investigated, as well as the evolution of inclusions during continuous casting. New information is obtained on the elongation of inclusions and formation of oxide–sulphide stringers during hot rolling. The results for the investigated steels show that with sulphur contents higher than 10 ppm, calcium aluminates were back-modified to alumina and spinel inclusions during casting. However, with decreasing sulphur contents, and adequate simultaneous calcium treatment of oxides, Al₂O₃ and spinel formation is hindered or even avoided. The most elongated inclusions are often also found in stringers. According to the results of this study, low melting calcium aluminate inclusions are not the most elongated oxide inclusions in the hot rolled product. With moderate calcium treatment, an optimal oxide composition can be obtained, found within the C12A7–CA–MgO composition. These liquid inclusions ensure good castability, while they do not easily elongate or fragment into detrimental stringers after continuous castingTiivistelmä Epämetalliset sulkeumat ovat väistämättä osa terästä, ja ne aiheuttavat ongelmia prosessille ja teräksen mekaanisille ominaisuuksille. Sulkeumien poiston sijaan niiden koostumusta muokataan kalsiumkäsittelyllä. Tällöin kiinteät alumiinioksidit muuttuvat vähemmän ongelmallisiksi suliksi kalsiumaluminaateiksi. Tämän työn päätavoitteena oli kehittää uusi sulkeumien tunnistus- ja luokittelumenetelmä. Sulkeuma-analyysien data voi jäädä hyödyntämättä, jos luokitteluun käytetään yksinkertaisia kriteerejä. Työssä esitetty menetelmä antaa parhaan arvion sulkeumissa olevista faaseista, mikäli sulkeumista ei ole alkuainekarttoja, joiden muodostaminen vie huomattavasti aikaa. Väitöskirjassa esitetään sulkeumien tunnistus- ja luokittelumenetelmän soveltamiskohteita. Menetelmän avulla tutkitaan sulkeumien muutosta ja jakaantumista sulan teräksen näytteenotossa ja sulkeumakuvan muutosta jatkuvavalun aikana. Uutta tietoa esitetään oksidi-sulfidiketjujen muodostumisesta kuumavalssauksen aikana. Tutkituilla teräksillä rikkipitoisuuden noustessa yli 10 ppm:n sulat kalsiumaluminaatit takaisinmuokkautuvat kiinteiksi alumiinioksideiksi tai spinelleiksi jatkuvavalun aikana. Riittävän matalalla rikkipitoisuudella ja kohtuullisella kalsiumkäsittelyllä alumiinioksidien ja spinellien muodostumista voidaan hillitä tai jopa estää se. Tutkimuksessa esitetään, että kuumavalssauksessa venyvimmät sulkeumat muodostavat myös lukuisten sulkeumien oksidi-sulfidiketjuja, jotka ovat tuotteen ominaisuuksien kannalta haitallisia. Tulosten mukaan kalsiumaluminaatit, jotka sulavat matalimmissa lämpötiloissa, eivät kuitenkaan ole taipuvaisimpia venymään valssauksessa. Maltillisella kalsiumkäsittelyllä saavutetaan optimaalinen oksidikoostumus C12A7–CA–MgO-faasiseurueesta. Nämä sulkeumat ovat sulia jatkuvavalussa varmistaen teräksen valettavuuden. Toisaalta ne eivät helposti veny tai rikkoonnu ketjuiksi valssauksessa jatkuvavalun jälkeen
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Pettersson, Hanna, and Elin Törnvall. "Efterbehandling av biogödsel : Ett försök med avskiljning och uppsamling av kväve och vatten genom ammoniakstripping i en efterhygieniseringsprocess." Thesis, Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-38018.
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During this master thesis, the possibility of ammonia removal from digestate in combination with after hygienization has been investigated. The aim of the work was to see how much ammonia that could be removed but also the properties of other process parameters such as TS/VS content, pH and alkalinity of the digestate. It was also of interest to study the energy balances for a process that combines ammonia stripping with after hygienization. The purpose of hygienization in a biogas plant is to kill pathogens. To study ammonia stripping combined with after hygienization, a prototype of an ammonia stripper was built in a laboratory. The digestate was heated to the hygienization temperature of 70 °C and air was led through with the help of a peristaltic pump by the end of the system. Condensate was trapped in a bottle by cooling the tube and the gases were brought to another bottle containing 1 M sulfuric acid. Ammonia and sulfuric acid reacted and formed ammonium sulfate. The process was also tested with closed system using vacuum to decrease the boiling point and thereby create more condensate. The results from the experiments showed that with an air stripping process most of the ammonium was trapped in the sulfuric acid while with a vacuum process more ammonium was trapped in the condensate. The most important parameters to achieve a good ammonia removal were air flow and time. With the vacuum system, more condensate was removed. The removal of condensate could make it possible to recirculate process fluid from the stripping process and thereby save energy in the centrifugation part which is used to create a solid part of the bio digestate. It was concluded from the experiments that air stripping is more effective when it comes to ammonium recovery. The process could be improved by using higher air flow which could decrease the time to less than one hour, which is the desired hygienization time. However, it is desired to keep the pump flow as low as possible since it is energy consuming. A chemical increase of the pH would also be of interest to try since previous tests showed a strong correlation between high pH-value and good ammonia stripping. More tests overall are of interest to ensure a reliable result. Still, the combination of after-hygienization and ammonia stripping would contribute to a better environment and a sustainable agriculture with a natural and nutritious digestate.
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Wirth, Benjamin [Verfasser], Peter [Akademischer Betreuer] Neubauer, Peter [Gutachter] Neubauer, Michael [Gutachter] Nelles, and Jan [Gutachter] Mumme. "Anaerobic treatment of liquid by-products from hydrothermal carbonization of biomass / Benjamin Wirth ; Gutachter: Peter Neubauer, Michael Nelles, Jan Mumme ; Betreuer: Peter Neubauer." Berlin : Technische Universität Berlin, 2021. http://d-nb.info/122950494X/34.
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