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Pěček, Jan. "Úprava kalů z čistíren odpadních vod před jejich dalším využitím." Doctoral thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2010. http://www.nusl.cz/ntk/nusl-233898.
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Industrial production of cellulose is an energy intensive process. Businesses aim to utilized as much input energy, materials as possible while minimizing the waste as well. In addition to the main product – cellulose and large amounts of organically polluted water which is subsequently treated in waste water treatment plants. This PhD thesis deals with formation of suitable mixing formula for sludge from cellulose production and available materials (waste) from close neighborhood of Biocel Paskov a.s. so that well balanced cofermentation products are achieved. This mainly involves grass from lawn maintenance, grass ensilage, potato peels, and leftovers from vegetable processing. Fermentation processes (both mesophilic and thermophilic) of prepared fermentation products were conducted in semi-continuous and continuous laboratory fermentation units. Reduction of organic mass depending on residence time was closely observed as well as production and quality of biogas along with quality of output digestate. Course of process behaviour under controlled pH was tested. Results of particular tests were integrated into graphs. Conclusion of the thesis presents balance scheme drawn for selected variants, and design of real fermentation station with individual buildings, operations, basic machinery and equipment description including investment costs. Financial calculation and expected investment return was conducted in two variants – without subsidies and including subsidies from Operational Programme Renewable Sources of Energy.
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Graan, Daniel, and Rasmus Bäckman. "Energy recovery at Chişinȃu wastewater treatment plant." Thesis, University of Skövde, School of Technology and Society, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-4080.
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<p>Possibilities for energy recovery from sludge at Chişinȃu wastewater treatment plant have been investigated and evaluated. One way of recovering energy from sludge is to produce biogas through anaerobic digestion. Which method of biogas usage that is to prefer in Chişinȃu has been evaluated from a cost-efficiency point of view. There is a possibility that a new waste incineration plant will be built next to the wastewater treatment plant, and therefore solutions that benefit from a co-operation have been discussed. The results show that biogas production would be suitable and profitable in a long time perspective if the gas is used for combined heat and power production. Though, the rather high, economical interest rates in Moldova are an obstacle for profitability.</p>
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Schrader, Guillo Alexander. "Direct nanofiltration of wastewater treatment plant effluent." Enschede : University of Twente [Host], 2006. http://doc.utwente.nl/55981.
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Justo, Llopis Ana. "Advanced technologies applied to wastewater treatment plant effluents." Doctoral thesis, Universitat de Barcelona, 2015. http://hdl.handle.net/10803/379819.
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This thesis is formed as a summary of publications developed in the Chemical Engineering Department from the University of Barcelona. The six publications of this thesis are focused on the application of advanced technologies to Wastewater Treatment Plant (WWTP) effluents that are usually discharged to the aquatic environment.
Water is an essential natural resource for the development of life and for human activities. Over the last few decades, water scarcity and water quality have become issues of major concern. Large amounts of water have been continuously contaminated, especially in developed countries. The restoration of water quality is essential to avoiding higher levels of contamination dealing with the "zero discharge" idea, and enabling water reuse. The implementation of tertiary treatments is necessary to reach the appropriate quality of water from effluents of WWTPs.
It is generally assumed that not all polluting agents are removed through conventional WWTPs. These persistent compounds include the emerging pollutants group, constituted by chemicals of high diverse origin. They are characterized by their high production and consumption volumes, which entails their continuous presence in the environment even at low concentrations. Whereas their occurrence is fairly well-established, their long-term effects and environmental consequences are not clearly identified. Thus, additional advanced treatment steps should be considered to reduce their discharge into receiving waters.
In this work, two groups of effluents that are usually discharge into water bodies without any extra treatment were treated: two types of secondary effluents and Reverse Osmosis (RO) brine effluent. Biologically treated sewage effluent contains a complex matrix of organic materials-Effluent Organic Matter (EfOM). This EfOM consisted of: refractory Natural Organic Matter (NOM), trace levels of synthetic organic compounds and soluble microbial products. Regarding RO, despite the high quality effluent generated, salts, biological constituents and organics, including micropollutants, are concentrated in the rejected effluent. Although their discharge is currently not regulated, safe environmental practices would suggest their treatment before its release and dilution into the environment.
Advanced Oxidation Processes (AOPs) appear to be appropriate for the treatment of waste streams that contains recalcitrant organic matter. These AOPs involves the in situ generation of highly reactive hydroxyl radicals (HO). This work is focused in the UV/H202 and ozonation treatments. On the other hand, taking advantage of the biodegradability enhancement achieved by AOPs, the use of subsequent biological step has been also integrated in order to minimize even further the organic load of the target effluent. The selected biological process was the Biological Activated Carbon (BAC) filter, where microbial communities were established on the exhausted porous of Granular Activated Carbon (GAC) surface.<br>Actualmente, la situación de escasez de agua y la calidad de la misma son cuestiones de gran preocupación a nivel mundial. Es por ello que, restablecer la calidad de las aguas que han sido previamente utilizadas, es esencial para evitar seguir contribuyendo a la contaminación del medio ambiente y caminando hacia el ideal de "vertido cero". Esta tesis, presentada como compendio de artículos, se ha centrado en la aplicación de tecnologías avanzadas para el tratamiento de efluentes procedentes de Estaciones Depuradoras de Aguas Residuales (WWTPs) que normalmente son vertidos al medio acuático sin tratamiento extra, y sin embargo contienen aún materia recalcitrante como por ejemplo, microcontaminantes. Los efluentes tratados han sido: efluentes secundarios procedentes de WWTPs municipales y procedente del efluente de rechazo producido en el tratamiento terciario con Ósmosis Inversa (RO).
Los tratamientos empleados han sido los Procesos de Oxidación Avanzada (AOPs) UV/H202 y ozonización, los cuales se caracterizan por la generación in situ de radicales hidroxilo de alto poder oxidante. Por otro lado, aprovechando que éstos son capaces de mejorar la biodegradabilidad del efluente tratado, también se ha estudiado la integración con tratamientos biológicos como son los filtros Biológicos de Carbón Activo (BAC). Esta tecnología aprovecha la saturación del Carbón Activo Granular (GAC) para la colonización de la biomasa en su superficie.
Por lo que respeta a efluentes secundarios, se ha caracterizado la Materia Orgánica del Efluente (EfOM) durante su oxidación con UV/H202 y ozono mediante la técnica de Cromatografía Líquida con Detección de Carbono Orgánico (LC-OCD). Se ha concluido que ambas técnicas parecen apropiadas para la oxidación de las diferentes fracciones de EfOM. No obstante, se han observado algunas diferencias en las características de las aguas resultantes debido a los diferentes mecanismos de oxidación implicados en los AOP utilizados.
Por otro lado, en los estudios realizados con efluentes de rechazo de RO, se ha evaluado la degradación de diferentes fármacos a diferentes dosis de oxidante aplicadas para ambos AOPs, así como la combinación de análisis químicos con bioensayos para caracterizar la eliminación de estos microcontaminantes. Por último, se ha evaluado la combinación de los tratamientos UV/H202 y ozonización con unos filtros Biológicos de Carbón Activo (BAC). Esta tecnología aprovecha la saturación del Carbón Activo Granular (GAC) para la colonización de la biomasa en su superficie. Los resultados han sido satisfactorios para todos los tratamientos propuestos, obteniendo cinéticas de degradación de fármacos diferentes en función del tratamiento aplicado y también de las características del efluente de rechazo. Los bioensayos aplicados han proporcionado información útil para una mejor caracterización de los efluentes resultantes. Por último, la integración de los AOPs como paso previo a un tratamiento biológico ha permitido reducir los parámetros típicos de calidad del agua significativamente.
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Rathore, Komal. "Dynamic Modeling of an Advanced Wastewater Treatment Plant." Scholar Commons, 2018. https://scholarcommons.usf.edu/etd/7354.
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Advanced wastewater treatment plants have complex biological kinetics, time variant influent rates and long processing times. The modeling and operation control of wastewater treatment plant gets complicated due to these characteristics. However, a robust operational system for a wastewater treatment plant is necessary to increase the efficiency of the plant, reduce energy cost and achieve environmental discharge limits. These discharge limits are set by the National Pollutant Discharge Elimination System (NPDES) for municipal and industrial wastewater treatment plants to limit the amount of nutrients being discharged into the aquatic systems.
This document summarizes the research to develop a supervisory operational and control system for the Valrico Advanced Wastewater Treatment Plant (AWWTP) in the Hillsborough County, Florida. The Valrico AWWTP uses biological treatment process and has four oxidation ditches with extended aeration where simultaneous nitrification and denitrification (SND) takes place. Each oxidation ditch has its own anaerobic basin where in the absence of oxygen, the growth of microorganisms is controlled and which in return also helps in biological phosphorus removal. The principle objective of this research was to develop a working model for the Valrico AWWTP using BioWin which mimics the current performance of the plant, predicts the future effluent behavior and allows the operators to take control actions based on the effluent results to maintain the discharge permit limits. Influent and experimental data from online and offline sources were used to tune the BioWin model for the Valrico Plant.
The validation and optimization of the BioWin model with plant data was done by running a series of simulations and carrying out sensitivity analysis on the model which also allowed the development of operation policies and control strategies. The control strategies were developed for the key variables such as aeration requirements in the oxidation ditch, recycle rates and wastage flow rates. A controller that manipulates the wasting flow rate based on the amount of mixed liquor suspended solids (MLSS) was incorporated in the model. The objective of this controller was to retain about 4500-4600 mg/L of MLSS in the oxidation ditch as it is maintained by the Valrico Plant. The Valrico AWWTP recycles around 80% of their effluent and hence, the split ratios were adjusted accordingly in the model to recycle the desired amount. The effluent concentrations from the BioWin model for the parameters such as Total Nitrogen (TN), Ammonia, Nitrate, Nitrite, Total Kjeldahl Nitrogen (TKN) complied with the discharge limits which is usually less than 2 mg/L for all the parameters.
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Perera, Kuruppu Arachchige Kalyani, University of Western Sydney, of Science Technology and Environment College, and of Science Food and Horticulture School. "Characteristics of a developing biofilm in a petrochemical wastewater treatment plant." THESIS_CSTE_SFH_Perera_K.xml, 2003. http://handle.uws.edu.au:8081/1959.7/777.
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A study was undertaken to investigate developing biofilms in a petrochemical wastewater treatment plant encompassing the architecture, microflora and the chemical nature of the matrix. Biofilms were developed on glass slides immersed in the activated sludge unit and analysed at known time intervals using a range of techniques. Initially, biofilms were investigated using conventional and emerging microscopic approaches to select a suitable technique. Scanning Confocal Laser Microscopy (SCLM) allowed visualisation of biofilms in situ with minimal background interference and non-destructive and optical sectioning which were amenable to quantitative computer-enhanced microscopy. SCLM was superior over Light microscopy and Scanning Electron Microscopy. This study demonstrated biofilm growth, presence of extracellular polymer substances (EPS) in early biofilms associated with cells and the development of porous nature of mature biofilms including channel-like structures. Overall new information has been obtained on developing biofilms in an Australian petrochemical wastewater treatment plant<br>Doctor of Philosophy (PhD) (Biological Sciences)
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Li, Wen. "Improvement of Biological Processes of Inland Municipal Wastewater Treatment Plant." Thesis, KTH, Mark- och vattenteknik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-190742.
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This master thesis gives an account for various aeration schemes that are utilized in conventional activated sludge treatment process in a wastewater treatment plant. By altering between different aeration schemes, the project aimed at reducing energy consumption along with maintaining the treatment performance at the plant. A series of experiments on the treatment performance over several different aeration schemes thus has been conducted on site at Solviken in Mora, Sweden. The project is basically a case study where no parameters were manually controlled except for the aeration schemes at the plant. Energy consumption reduction is logically relative to the ratio between aeration and non-aeration intervals. Several criteria were tested in regards to the treatment performance, including pH value, organic matters, phosphorus substances and microorganisms. The study has come up with a superior aeration scheme for the plant, as well as indicated processes that can be improved at the plant.
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Novák, Jan. "Kanalizace a ČOV Křelov,Břuchotín-stavebně technologický projekt." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2014. http://www.nusl.cz/ntk/nusl-227063.
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The subject of my work is to lower construction site waste water treatment plant Křelov - Břuchotín. In more detail, I focused mainly on the implementation of the circular tanks sewage treatment plant. These tanks prescription processing technology formwork and concreting circular tanks. It also contains a technical report, technical report building equipment, a study of the main technological stages of the building, site, design of mechanical assembly, inspection and test plan solved the technological regulation and scheduling.
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Addison, Jesse Ward. "The formation of halonitromethanes in wastewater treatment plant effluents." Connect to this title online, 2008. http://etd.lib.clemson.edu/documents/1211390627/.
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Wan, Ka-hung, and 溫家雄. "Computer simulation of a local municipal wastewater treatment plant." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1996. http://hub.hku.hk/bib/B43893685.
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Wan, Ka-hung. "Computer simulation of a local municipal wastewater treatment plant." Hong Kong : University of Hong Kong, 1996. http://sunzi.lib.hku.hk/hkuto/record.jsp?B17508939.
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Thavamani, Dhakshinamoorthy. "Estimation of Renewable Energy for a Wastewater Treatment Plant." University of Toledo / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1302035804.
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Pereira, Sofia Filipe. "Modelling of a wastewater treatment plant using GPS-X." Master's thesis, Faculdade de Ciências e Tecnologia, 2014. http://hdl.handle.net/10362/13621.
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Dissertation to obtain the degree of Master in Chemical and Biochemical Engineering<br>The work present in this thesis was conducted in Portucel Soporcel mill, in the industrial complex of Setúbal, and had as main objective the modelling of the treatment process of the effluents from this industry, using for this purpose the software GPS-X. This program has a clear-cut graphical interface and uses a specialized translator that converts the graphical process into material balance equations, based on dynamic models. These models allow, besides the kinetic descripton of the treatment process carried out at the WWTP, to simulate new scenarios towards the study of critical parameters for the process as well as optimization and control of the WWTP.
The effluent that arrives to Portucel’s WWTP, from the pulp and paper mills of the complex, is particularly rich on fibers (solids), lignin, chlorinated and sulphur compounds, resin acids, phenols and starch. It has a brown colour due to the presence of lignin and has a high oxygen chemical demand (about 1,095 g O2/m3). The WWTP uses the activated sludge process with extended aeration. This method allows an efficient removal of organics at the same time as it minimizes the sludge production.
For the modelling of the process it was necessary to collect historical data related to the WWTP’s performance over the last 3 years. This data was used as input values for the influent characterisation and as output values to achieve the treated effluent characterisation. Since the first simulation did not lead to the desired output results, it was necessary to proceed to the model calibration, by means of a more detailed study concerning the nutrient and organic fractions of the influent.
Once the model was calibrated, a study of the urea flowrate was conducted. The urea is added to the influent, before the beginning of the biological oxidation, as a way to satisfy the nitrogen requirements along the treatment process. However, this flowrate was never submitted to a study that evaluated, in a higher detail, the effective requirements of this nutrient. Thus, some simulations were done using the software, by decreasing successively the value of the urea flowrate and the results obtained were analyzed. Furthermore, these simulations were validated in the WWTP itself, at Portucel, through the decrease of the urea flowrate to half the normal value. Both the simulations and Portucel’s results showed that, actually, the addition of urea is not necessary because it does not affect the treatment process in a significant way, namely in terms of the removal of chemical oxygen demand. The simulations have also showed that the concentration of nitrogen in the final effluent diminishes significantly with the reduction of the urea flowrate, which could be advantageous in an environmental point of view.
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Brown, Vanessa Ruth. "The microbiology of an activated sludge plant involved in the treatment of xenobiotic compounds." Thesis, University of Leeds, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.328895.
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Guest, Adam Julian. "Studies on a novel aerator for wastewater treatment." Thesis, Liverpool John Moores University, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.313135.
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Tan, Hanji. "Microwave enhanced advanced oxidation treatment of sludge from a municipal wastewater treatment plant." Thesis, University of British Columbia, 2017. http://hdl.handle.net/2429/62758.
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It has been proven that microwave enhanced advanced oxidation process (MW-AOP) has an outstanding treatment efficiency on the organic slurries, such as sewage sludge and dairy manure (liquid portion), yet the treatment efficiencies on different substrates remain unknown. This study was carried out to: 1) identify the effects of MW-AOP on different types of sludge, 2) evaluate the effects of flowrates and solids concentrations on the heating profile, 3) evaluate the MW-AOP treatment efficiencies of secondary sludge at 90 and 110 ºC, and 4) examine the treatment efficiencies of MW-AOP of dairy manure (liquid portion).
The study on the sludge was to evaluate treatment efficiencies of different sludge (primary sludge, secondary sludge, and anaerobic digested sludge) and the centrate by the MW-AOP. The results indicated that the secondary sludge was most suitable for the MW-AOP treatment. This is because secondary sludge had the highest number of solids and phosphorus contents, but also yielded the highest soluble materials.
The pilot-scale 915 MHz MW-AOP system was used to treat the secondary sludge at 90 and 110ºC, which suggested that higher temperature would favor nutrients release. The dewaterability of treated sludge improved significantly at both temperatures.
The pilot-scale 915 MHz continuous flow MW-AOP system was also tested with salt water at different flowrates and salt concentrations to understand the heating and power consumption profile of the system. Among the flowrates (6, 7.5, 9 L/min) and salt concentrations (10 mg/L to 120 mg/L) examined, the total energy consumption increased with an increase of salt concentration, while flowrates had lesser effect. In contrast, the temperature rise was more rapid with lower salt concentrations. The overall heating rate was similar for different flowrates.
Similar to secondary sludge, the pilot-scale 915 MHz continuous flow MW-AOP system was used to treat dairy manure (liquid portion). The results suggested a sound treatment efficiency, with an increase from 3% to up to 90% of soluble TP/TP, which enhances subsequent struvite recovery. Both the ratios of soluble TP/TP and of ortho-P/soluble TP were favored by higher temperatures.<br>Applied Science, Faculty of<br>Civil Engineering, Department of<br>Graduate
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Fornander, Erik. "Ozone Treatment Targeting Pharmaceutical Residues : Validation and Process Control in a Wastewater Treatment Plant." Thesis, Linköpings universitet, Teknisk biologi, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-154012.
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Major studies conducted in Europe and North America has concluded that the current processes in wastewater treatment plants insufficiently degrade micropollutants e.g. pharmaceutical residues. Several sorption and oxidation methods has therefore been investigated with the purpose of removing or degrading micropollutants in wastewater. The main purpose of this project was, firstly, to validate the results from a pilot study conducted by Tekniska verken i Linköping AB (2014) which investigated the use of ozone to degrade pharmaceutical residues. Secondly, to investigate and design a suitable process control strategy for the ozonation process. Four different tests were conducted during the project, a dose-response test, step-response tests, a trace test, and a performance test. A poorer average reduction of pharmaceutical residues was observed in this project compared to the pilot study. An average reduction of approximately 80% was observed at the highest tested dose, 0.67 mg O3/mg DOC, N corr. Whilst an average reduction of 90% was observed at approximately 0.46 mg O3/mg DOC, N corr, in the pilot study. However, the quality of the wastewater was worse during this project compared to the pilot study. ΔUVA254 and offgas concentration of ozone were found to be suitable control parameters for process control. A control strategy based on a combination of these parameters was designed, where ΔUVA254 was used as the main control parameter and the off-gas concentration of ozone was used as a limiting controller to ensure a sufficient mass transfer in the system. In conclusion, a suitable flow proportional base ozone dose valid for current water conditions has been identified, 10 mg/L. Differences in wastewater quality which heavily influence the ozonation process have been identified. Lastly, a control strategy for process control of the ozonation have been identified, designed and is ready for implementation.
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Litteken, Garrett Michael. "IMPACT OF WATER TREATMENT PLANT ALUM SLUDGE RESIDUALS ON WASTEWATER TREATMENT PLANT BIOLOGICAL PROCESSES: A CASE STUDY." OpenSIUC, 2017. https://opensiuc.lib.siu.edu/theses/2246.
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Water treatment plant (WTP) residual discharge is considered a pollutant and requires treatment to prevent negative impacts when released to the environment. As regulatory requirement becomes increasingly strict, WTPs are required to find suitable methods for the treatment of sludge residuals. Wastewater treatment plants(WWTP) provide existing treatment methods to remove contaminants from WTP residuals. A case study on the Carbondale Water Treatment Plant (CWTP) and receiving Carbondale Southeast Waste Water Treatment Plant (SEWWTP) provided an opportunity to quantify potential negative impacts for the discharge of residual alum sludge to a biologic sludge digestion plant. The first part of the study focused on quantifying changes to the SEWWTP loading conditions from the addition of metal salt coagulant water treatment residuals discharged by the CWTP. Historic sludge quantities and treatment methodologies for both the CWTP and SEWWTP were used to predict loading conditions and residual concentrations at the SEWWTP. Ammonia, BOD, pH, and TSS concentrations from the CWTP were not identified to significantly impact the existing concentrations at the SEWWTP. Metals concentrations from the CWTP were also found to fall within WWTP regulatory quantities. The second part of the study evaluated potential impacts to beneficial bacteria populations in the SEWWTP oxidation ditch from the receipt of CWTP alum residuals. Studies of residual alum sludge impacts to beneficial bacterial populations are rare, and often do not translate from one treatment plants processes to the next. The SEWWTP employs a multi-ring oxidation ditch with an anoxic outer ring and aerobic middle and inner rings. Biologic Activity Reaction Tests (BART) were used to isolate beneficial bacteria species typically present in oxidation ditches including heterotrophic aerobic bacteria, denitrifying bacteria, and nitrifying bacteria. Heterotrophic aerobic bacteria and denitrifying bacteria are the predominant beneficial bacteria species in the outer ring, while nitrifying bacteria and heterotrophic aerobic bacteria dominate the aerobic inner rings. Heterotrophic aerobic bacteria and denitrifying bacteria populations identified in the outer ring of the oxidation ditch did not demonstrate any population impacts from the receipt of residual alum sludge. In addition, nitrifying bacteria populations and heterotrophic aerobic bacteria population demonstrated no impacts from the introduction of CWTP residual alum waste to the aerobic inner ring of the oxidation ditch. Overall, the study demonstrated the treatment of residual alum sludge from a WTP is possible through the existing biological processes at a WWTP.
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Basu, Pradipta Ranjan. "Evaluation of biological treatment for the degradation of petroleum hydrocarbons in a wastewater treatment plant." Texas A&M University, 2005. http://hdl.handle.net/1969.1/2418.
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Biodegradation of petroleum hydrocarbon can be an effective treatment method
applied to control oil pollution in both fresh water and marine environments.
Hydrocarbon degraders, both indigenous and exogenous, are responsible for utilizing
petroleum hydrocarbon as their substrate for growth and energy, thereby degrading
them. Biodegradation of hydrocarbons is often enhanced by bioaugmentation and
biostimulation depending on the contaminated environment and the competence of the
hydrocarbon degraders present. An evaluation of the performance of the biological
treatment of petroleum hydrocarbon by the hydrocarbon degrading microbes at the
Brayton Fire School??s 4 million gallon per day (MGD) wastewater treatment plant was
the main research objective. Samples were taken for two seasons, winter (Nov 03 ?? Jan
03) and summer (Jun 04 ?? Aug 04), from each of the four treatment units: the inlet tank,
equalization tank, aeration tank and the outfall tank. The population of aliphatic
hydrocarbon degraders were enumerated and nutrient availability in the system were
used to evaluate the effectiveness of on-going bioaugmentation and biostimulation.
Monitoring of general effluent parameters was conducted to evaluate the treatment
plant??s removal efficiency and to determine if effluent discharge was in compliance with
the TCEQ permit. The aeration tank is an activated sludge system with no recycling.
Hydrocarbon degraders are supplied at a constant rate with additional nutrient
supplement. There was a significant decrease in the population of microbes that was
originally fed to the system and the quantity resident in the aeration tank. Nutrient levels
in the aeration tank were insufficient for the concentration of hydrocarbon degraders,
even after the application of dog food as a biostimulant. The use of dog food is not
recommended as a nutrient supplement. Adding dog food increases the nitrogen and
phosphorus concentration in the aeration tank but the amount of carbon being added with
the dog food increases the total chemical oxygen demand (COD) and biochemical
oxygen demand (BOD). An increase in the concentration of total COD and BOD further
increases the nitrogen and phosphorus requirement in the system. The main objective of
supplying adequate nutrients to the hydrocarbon degraders would never be achieved as
there would be an additional demand of nutrients to degrade the added carbon source.
This research study was conducted to identify the drawbacks in the treatment plant
which needs further investigation to improve efficiency.
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Taylor, Carrie Renee. "Selecting plant species to optimize wastewater treatment in constructed wetlands." Thesis, Montana State University, 2009. http://etd.lib.montana.edu/etd/2009/taylor/TaylorC0509.pdf.
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Constructed wetlands are used around the world for treating domestic, agricultural, and industrial wastewater, stormwater runoff, and acid mine drainage. Plants may affect efficacy of wastewater treatment through their influence on microbial activity by creating attachment sites and releasing carbon exudates and oxygen. My research investigated seasonal plant effects on wastewater treatment by monitoring water chemistry in model subsurface wetlands planted with monocultures of 19 plant species and unplanted controls. Chemical oxygen demand (COD) removal, an indicator of water quality, declined during colder temperatures in the unplanted control, likely caused by a decrease in microbial activity. In contrast, wetlands with most plant species had constant COD removal across seasons. Redox potential and sulfate concentrations were measured as indirect measurements of the oxygenation of the wastewater. Wetlands that had a decline in COD removal during cold temperatures had constant low redox potential and sulfate concentrations throughout the seasons. Wetlands with high COD removal across seasons had elevated redox potentials and sulfate concentrations during the winter, indicating elevated oxygen availability, which may offset the negative temperature effect on microbial processes. I measured root oxygen loss (ROL) in the summer and the winter to determine whether oxygen release was sufficient to influence wastewater treatment and cause seasonal and species-specific effects on water chemistry. COD removal and ROL were positively correlated at 4°C but not at 24°C; however, the amount of root oxygen release only accounted for a portion of the required oxygen to facilitate plant's influence on COD removal. Flooding tolerance was quantified for each species by comparing plants' biomass between flooded and drained conditions. Plants' botanical grouping, Wetland Indicator Status, and flooding tolerance were compared to plants' influences on wastewater treatment to determine whether easily measured plant traits can be used to identify plants that will optimize wastewater treatment. All the sedges and rushes, obligate wetlands species, and 8 of 9 flood-tolerant plants had greater COD removal than the control at 4°C, the coldest temperature incubation. These results can be applied for wetland design by selecting plant species to optimize wastewater treatment, especially in cold climates.
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Bermudez, Vivian. "Biofiltration for Control of H2S from Wastewater Treatment Plant Gases." ScholarWorks@UNO, 2003. http://scholarworks.uno.edu/td/9.
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A low-cost and efficient methodology was used to test the performance of a biofilter removing gaseous hydrogen sulfide generated in the headworks and a primary clarifier of a local Wastewater Treatment Plant. The contaminated gas stream is distributed upward through 1,718 m3 of filter material. With a flow rate varying between 3,503.0 m3/h and 4,587.3 m3/h and hydrogen sulfide inlet concentrations between 0.8 and 146 ppm, hydrogen sulfide was efficiently eliminated by the wood bark biofilter. The removal efficiencies ranged from 97.5% to 99.9%. The mean water content of the filter material was determined to be 67.1%. The excess water existing in the unit and long residence times may have provided the appropriate conditions for a high hydrogen sulfide removal.
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Puga, Gil Ursinio. "Ultraviolet Disinfection Pilot Study at the Fargo Wastewater Treatment Plant." Thesis, North Dakota State University, 2017. https://hdl.handle.net/10365/28690.
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A pilot study was carried out at the Fargo wastewater treatment plant to determine the impacts that flow rate, water quality, and system fouling may have on the efficiency of UV disinfection. A second-order model successfully explained the results obtained with the collimated beam. The second-order model was used to study the impact of water quality and initial microorganism concentration on E. coli inactivation rates. Fouling material was mostly made of precipitated metal salts and its impact on UV intensity reduction was explained with the application of the Beer-Lambert law. E. coli inactivation in the pilot unit was found to be dependent on UVT, flow rate, and UV intensity. A first-order plug-flow model successfully explained the inactivation data obtained in the pilot unit. No significant seasonal water quality changes that may affect system operation were identified. However, UVT changes caused by storm events had short-term adverse impacts on system performance.
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Ekman, Malin. "Environmental Impacts of a Wastewater Treatment Plant – With Sidestream Deammonification." Thesis, KTH, Skolan för kemi, bioteknologi och hälsa (CBH), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-280165.
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Människan ger upphov till avloppsvatten varje dag. Kommunalt avloppsvatten är rikt på kol, kväve och fosfor, vilka har en stor miljöpåverkan. Vattenrening är i och med detta en nödvändighet för att minimera den antropogena inverkan på naturen och den biologiska mångfalden. Genom att rena vatten i avloppsreningsverk så kan halterna av dessa ämnen reduceras markant. Ett av många reningsverk är Himmerfjärdsverket som är beläget i Sverige, som bland annat använder deammonifikation vilket är en vattenreningsmetod för att rena ammoniumrikt avloppsvatten. I det här examensarbetet genomförs en livscykelanalys för att utvärdera hela reningsverkets miljöprofil under år 2019 och år 2015. Dessa två år använder sig utav två olika deammonifikationsmetoder, nämligen DEMON och DeAmmon. Resultaten utvärderas enligt följande miljöpåverkanskategorier: växthuseffekt, övergödning i marina- och sötvattensekosystem, humantoxicitet, ozonnedbrytning och försurning. Livscykelanalysen genomfördes i mjukvaran GaBi med ecoinvent version 3.3 som databas och ReCiPe som metod. Resultaten tyder på att de största bidragande orsakerna till miljöpåverkan beror på anaerob rötning av slam, vilket är en process som stabiliserar slam och även från utsläpp till mark som uppkommer genom deponering av rötat slam. Andra faktorer som bidrar till miljöpåverkan är kemikalier, utsläpp av det behandlade avloppsvattnet och övriga uppkomna utsläpp från olika processer. Inom analysens gränser så dras även slutsatsen att det inte är någon markant skillnad på de två reningsmetoderna.<br>We, the humans, give rise to wastewater everyday. Municipal wastewater is rich in carbon, nitrogen and phosphorus, of which have large impacts on the environment. Wastewater treatment is therefore a necessity to minimize the anthropogenic impacts on both nature and biodiversity. To reduce the content of these substances, the wastewater is treated in wastewater treatment plants. One of them is Himmerfjärdsverket located in Sweden that uses, among others, deammonification of which is a biological technology for treating ammonium rich wastewaters. In this thesis, a life cycle assessment is conducted in order to do an overall evaluation of the environmental profile of this entire plant during two different years, 2019 and 2015. These years also have different deammonification technologies implemented, DEMON and DeAmmon. The results are evaluated upon the following impact categories: climate change, freshwater and marine eutrophication, human toxicity, ozone depletion and acidification.The impact assessment is conducted in GaBi software with the database ecoinvent version 3.3 and ReCiPe as method. Results indicate that the main contributors to pollution are due to anaerobic digestion, which is a process that stabilize sludge and also from emissions to soil that arise from disposal of digested sludge. Other large impacts come from chemicals that are added to the process, the effluent and other arising emissions from the different processes. It is further concluded that there are no major differences between the two deammonification technologies within the boundaries of this assessment.
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Milathianakis, Emmanouil. "Modelling and future performance assessment of Duvbacken wastewater treatment plant." Thesis, KTH, Mark- och vattenteknik (flyttat 20130630), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-210704.
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Duvbacken wastewater treatment plant in Gävle, Sweden, currently designed for 100,000 person equivalent (P.E.) is looking for a new permit for 120,000 P.E. due to the expected increase of the population in the community. Moreover, the recipient of the plant’s effluent water was characterized as eutrophic in 2009. The plant emissions are regulated regarding seven days biological oxygen demand (BOD7) and total phosphorus (Ptot) emissions. Yet, there is no available computer model to simulate the plant operations and investigate the emissions of the requested permit. However, it was uncertain if the available data would be sufficient for the development of a new model. A model of the plant was eventually developed in BioWin® software under a number of assumptions and simplifications. A sensitivity analysis was conducted and used conversely than in other studies. The sensitivity analysis was conducted for the uncalibrated model in order to indicate its sensitive parameters. The parameters of substrate half saturation constant for ordinary heterotrophic organisms (KS) and phosphorus/acetate release ratio for polyphosphate accumulating organisms (YP/acetic) were finally used for model calibration. Following, the model validation confirmed the correctness of the calibrated model and the ability to develop a basic model under data deficiency. The new model was used to investigate a loading scenario corresponding to 120,000 P.E. where plant emissions that meet the current permits were predicted. Some suggestions proposed were the installation of disc filters in order to further reduce the effluent phosphorus and BOD precipitation in cases of high influent concentrations. In case of the application of a nitrogen (N) permit, the installation of membrane bioreactors and a full-scale chemical P removal was proposed as an alternative that will require a smaller footprint expansion of the plant.
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Mackley, Tim. "Design and evaluation of a novel wastewater treatment package plant." Thesis, Cranfield University, 2007. http://dspace.lib.cranfield.ac.uk/handle/1826/11185.
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The
objective of the project was to develop a novel package plant using available
process technologies that would be competitive in the domestic waste water treatment
market.
A market
analysis identified the business opportunity for Balmoral Tanks to develop a
package plant with higher treatment capability than its current product. A customer
survey and a review of Regulatory standards provided valuable input into the design
considerations for the
package plant.
A review of available
process technologies and materials of construction resulted in
the selection of a
Moving Bed Biolm Reactor (MBBR) process and High Density
Polyethylene material as the optimum design basis for the package plant.
A detailed
design exercise scoped out and specified all the components of the MBBR
package plant.
A four month duration
programme for testing the prototype at Cranfield University
facilities was devised which
satisfactorily simulated typical domestic wastewater
treatment
operating conditions. Test rig problems associated with very low ambient
temperatures were experienced in the early stages of testing and were identified and
resolved. The
prototype package plant unit subsequently operated satisfactorily and the
performance was demonstrated to meet all the wastewater constituent removal design
specifications. The MBBR process performance was shown to be consistent with
published findings of other researchers.
Novel fabrication methods
developed by Balmoral Tanks resulted in the cost of the
new MBBR
package plant being only 3% higher than that of Balmoral Tanks current
lower
specification product.
The new MBBR
package plant is shown to be a potentially very marketable domestic
wastewater treatment
product.
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Cadwallader, Adam L. "Impacts of Bromide and Nitrogen Wastewater Discharges on Downstream Drinking Water Treatment Plant Disinfection Byproducts." Research Showcase @ CMU, 2018. http://repository.cmu.edu/dissertations/1132.
Full textAbstract:
Bromide and nitrogen are wastewater effluent constituents that have raised concern for their potential to affect disinfection byproduct (DBP) formation at drinking water treatment plants (DWTPs) downstream of wastewater discharges. Despite the toxicity of brominated and nitrogenous DBPs, wastewater treatment does not usually remove bromide and nitrogen prior to discharge. Bromide is a conservative chemical and thus is not removed from surface waters via natural transformations after being released, although it may be diluted. Nitrogen is biologically reactive; it can be transformed and removed by bacteria in the environment and in wastewater treatment plants (WWTPs). While this nitrogen cycling may reduce impacts on downstream DWTPs, it also produces nitrous oxide (N2O), a greenhouse gas, as a byproduct. Thus, interaction with the environment alters the potential impact of bromide and nitrogen on drinking water systems. The objective of this work was to examine the impacts of nitrogen and bromide present in wastewater effluent on DBP formation at downstream DWTPs, within the context of current and possible future DBP regulations. Three major conclusions were reached. First, within Southwestern Pennsylvania, an area where surface water bromide concentrations have increased due to fossil fuel extraction-based wastewater discharge, no statistically significant improvement in species-specific risk was observed over the past 20 years, despite decreasing TTHM levels. Second, nitrogen treatment decisions at WWTPs influence the formation of N-nitrosodimethylamine (NDMA), an unregulated but toxic DBP, at downstream DWTPs in areas of high de facto reuse (DFR). More plants using nitrifying wastewater treatment resulted in significantly lower NDMA detection rates and concentrations observed at chloraminating DWTPs located downstream. Third, the current approach to estimating national emissions of N2O related to wastewater treatment may underestimate emissions by an order of magnitude. Further, nitrogen removal at wastewater treatment plants reduces total N2O emissions attributable to wastewater treatment by reducing the N2O that would be generated in receiving surface waters. Thus, in both cases, impacts of WWTPs on downstream DWTP DBPs were observable. While natural cycling may remove nitrogen from surface water, in-plant removal of nitrogen prevents large amounts of N2O emissions.
27
Jiwani, Ashifa. "Influence of plant operating conditions on the dewaterability of surplus activated sludge." Thesis, Imperial College London, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.243950.
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Wu, William Ying Xin. "Development of a plant-wide steady-state wastewater treatment plant design and analysis program." Master's thesis, University of Cape Town, 2015. http://hdl.handle.net/11427/13724.
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Models are used as prognostic and diagnostic tools in order to design, analyse and optimise the biological and physical processes in a wastewater treatment plant (WWTP). This is done in order to save time and money and to improve the understanding of the behaviour of the treatment system. There are two categories of models in wastewater (WW) treatments, steady-state and dynamic models. (i) Dynamic models consist of sophisticated mathematical solvers and are structured for the optimisation of WWTP’s and not for system sizing. (ii) Steady-state models comprise simple and explicit algebraic equations. With these equations, high-level answers are found easily and quickly but with a much lower level of input information. Hence, steady-state models allow for system sizing and are powerful pre-processors for dynamic models. They can generate the overall WWTP scheme, main system defining parameters, and the initial conditions for starting the dynamic simulation. Currently, there is a lack of a plant-wide steady state design (PWSSD) program. Numerous steady-state models for the different unit processes exist; however, they are yet to be integrated and presented in one holistic software package for the plant-wide design (and analysis) of WWTP. The availability of such program will be extremely beneficial to WWTP engineers as it can be used as a standalone tool for the steady state design, system sizing and capacity estimation, or as a pre-processor to generate the plant wide WWTP initial conditions for dynamic simulation. To fill the above-mentioned software gap, a PWSSD program was developed within the Excel/VBA environment. The developed PWSSD program integrates various steady-state wastewater treatment models with an expert-guided user-interface, thereby creating a platform for step-by-step assisted interaction and exploration of the models. This program draws upon a large body of literature regarding the modelling of wastewater treatment processes. The current version of the program (1) caters for commonly used AS configurations (MLE, JHB and UCT) in South Africa. The steady-state AS models are holistically linked to important upstream and downstream biological and non-biological treatment processes.
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Perera, Kuruppu Arachchige Kalyani. "Characteristics of a developing biofilm in a petrochemical wastewater treatment plant /." View thesis, 2003. http://library.uws.edu.au/adt-NUWS/public/adt-NUWS20060516.122048/index.html.
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Thesis (Ph.D.) (Biological Sciences) -- University of Western Sydney, 2003.<br>"Thesis submitted for the Degree of Doctor of Philosophy, University of Western Sydney, July 2003". Includes bibliography : leaves 253 - 276.
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Buck, Andrew. "Characterisation of chemical processes operating within a biological wastewater treatment plant." Thesis, Open University, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.409874.
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31
Figinsky, Felicia R. "Odor Monitoring at the New Orleans East Bank Wastewater Treatment Plant." ScholarWorks@UNO, 2016. http://scholarworks.uno.edu/td/2145.
Full textAbstract:
Hydrogen Sulfide is a corrosive, odorous, and hazardous gas that can cause issues for wastewater collection systems and treatment plants. When evaluating hydrogen sulfide concentrations it is important to consider the source, odor causing mechanism, and its level of toxicity. In this study, continuous hydrogen sulfide monitoring was performed for 8 locations within the New Orleans East Bank Wastewater Treatment Plant for a span of 5 months. Hot spots within the plant are located and data analysis is performed based on daily and hourly averages of hydrogen sulfide concentrations. The data was configured to show peak hydrogen sulfide concentrations at specific time intervals throughout the day.
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Ndeba, Nganongo Lionnel Neddy Aymar. "Process simulation for a small-scale poultry slaughterhouse wastewater treatment plant." Thesis, Cape Peninsula University of Technology, 2018. http://hdl.handle.net/20.500.11838/2886.
Full textAbstract:
Thesis (Master of Environmental Management)--Cape Peninsula University of Technology, 2018.<br>Fresh water is a renewable resource, but it is also finite, especially given environmental
impacts from anthropogenic activities. Globally, there are countless signs that untreated
industrial discharge into fresh watercourses is one of the main causes of ecosystem
degradation. Poultry slaughterhouse wastewater (PSW) amongst the main pollutants of fresh
water sources. In recent years, the world’s pre-eminent researchers have developed
innovative wastewater treatment processes to treat the large quantity of wastewater
generated as well as to manage the environmental health concerns arising from PSW
discharged into the environment. Furthermore, increasing wastewater treatment capital costs
and the implementation of increasingly rigorous government legislation to mitigate
environmental pollution whilst minimizing fresh water source contamination, requires that
wastewater such as PSW, be adequately treated prior to discharge.
In order to assist the small-scale poultry producers in South Africa (SA), process simulation
for a small-scale poultry slaughterhouse wastewater treatment plant was proposed using
Sumo Wastewater treatment plant (WWTP) simulation software. Sumo is an innovative and
most versatile wastewater simulation package on the market. The simulator is capable of
modelling treatment plants of unlimited complexity, focusing largely on Biochemical oxygen
demand (BOD), Chemical oxygen demand (COD), nitrogen and phosphorus removal; with
digester, and side streams design options, being available. Considering the possible
advantages in modelling and ongoing studies of implementing wastewater treatment to
increase water management, anaerobic digestion of high strength wastewater such as PSW,
warranted this research study. Model development from the simulation included the
evaluation of numerous design options to assist small scale poultry producers, to have a
variety of designs to choose from in their PSW WWTP designs.
With the aid of Sumo, two models were designed in this study, namely a single-stage and a
two-stage anaerobic digestion without a recycle. The PSW used as feed was obtained from
a local poultry slaughterhouse (Western Cape, South Africa). Both model designs predicted
the reduction of the organic matter (COD, BOD5) total suspended solids (TSS), and volatile
suspended solids (VSS) in the PSW. The digester for the single stage anaerobic digestion
system modelled was set to operate at steady state for 150 days under mesophilic
temperature (35 ˚C) with a solid retention time (SRT) of 25 days. The COD, TSS, VSS and
BOD removal efficiencies reached a maximum of 64%, 77%, 84%, and 94%, respectively, at
an organic load rate (OLR) of 143.6 mg COD/L/day. A minute increase in the ammonia
(NH3) and phosphate (PO3-
4) concentration was observed once the simulation was
completed.
As for the two-stage anaerobic digestion system, both digesters were set to perform at
mesophilic temperatures (35 ˚C) and a SRT of 13 days in the first digester and 25 days in
the subsequent digester. The two-stage anaerobic digestion showed better performance in
comparison to the single-stage anaerobic digestion system. The COD, TSS, VSS and BOD5
removal efficiencies reached a maximum of 69%, 79%, 85%, and 96%, respectively, at an at
an OLR of 143.6 mg COD/L/day. A similar trend regarding phosphate and ammonia removal
was noticed in the two-stage anaerobic digestion, suggesting a tertiary treatment system to
be in place for further treatment.
Although, the two-stage anaerobic digestion demonstrated adequate performance, for the
purpose of this study, the single-stage was the process recommended for PSW treatment,
as it is less costly and will be suitable for small scale poultry producers; albeit biogas
production is much higher when digesters are connected in series.
The PSW treatment modelling for this study was successfully employed with the resultant
effluent being compliant with the City of Cape Town (CCT) wastewater and industrial effluent
by-law discharge limits. Although, both the PO3-
4 and NH3 were suggested to require further
monitoring.
Therefore, the poultry slaughterhouse from which the PSW was obtained will be able to
safely discharge the treated wastewater proposed in this research into local water bodies,
i.e. rivers in the Western Cape, SA; however, the treated PSW will not be suitable for re-use
as process water.
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Nkadimeng, Lefa Steven. "Maximising energy recovery from the brewery wastewater treatment system: a study evaluating the anaerobic digestion wastewater treatment plant at SAB's newlands brewery." Master's thesis, University of Cape Town, 2015. http://hdl.handle.net/11427/13707.
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Includes bibliography.<br>This study has been encouraged by the successful recovery of useful energy from brewery wastewater using anaerobic digestion technology. It aims to evaluate the environmental benefits or burden of improving energy production by using organic brewery by-products as additional feedstock into the SABWTP. An environmental impact assessment on the SABWTP and its associated process was carried out using life cycle assessment (LCA) tools. Anaerobic digestibility of the two major organic brewery by-products, brewer’s spent grain and brewer’s spent yeast, was evaluated experimentally using laboratory bench scale reactors. The results were used to postulate the feasibility of adding these feedstocks into the SABWTP. Based on these findings, three viable processing scenarios were synthesised and assessed in terms of environmental impact analysis. In the environmental impact analysis, the three scenarios were compared using average process conditions and the main contributing factors to environmental burdens associated with each scenario were identified.
34
Johansson, Emmy. "Disinfection of Wastewater with Sodium Hypochlorite : And how it Might be Applied at Slottshagen Wastewater Treatment Plant." Thesis, Linköpings universitet, Institutionen för fysik, kemi och biologi, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-175172.
Full textAbstract:
The disinfection of wastewater is not something that is currently in use at any wastewater treatmentplant in Sweden. The government has however stated some requirements for some wastewatertreatment plants to have a plan to implement disinfection in their treatment process, if asked.Therefore the goal of the project is to research if disinfection with sodium hypochlorite can beimplemented at Slottshagen wastewater treatment plant. There are several factors that will affect the efficacy of the disinfection of the wastewater. Firstly, thedisinfection process is dependent on the pH of the water solution. This is because the weakhypochlorous acid has better disinfection than the hypochlorite ion, and hypochlorous acid is presentthe most in the solution at pH 3-6. Another factor that is important to consider is the amounts ofnutrients present in the solution, since the chlorine oxidizes the nutrients rather than reacting with theorganisms in the solution. Some of the products from the oxidation of the nutrients are bad for bothhuman health and the environment. Also the temperature of the water and the concentration of thechlorine will affect the disinfection. Lastly, depending on which organism that is sought out to bedisinfected, the chlorine will have more or less effect on that particular organism. To research the chlorination effect, different additions of sodium hypochlorite were added to samplesolutions from the treatment plant and got to react in the solution for 5 minutes. Following thesamples were neutralized with ascorbic acid, and the amount of E. coli , coliform bacteria andintestinal enterococci were analyzed. The disinfection of the water during 1,5 minutes and at a shortertemperature were also analyzed. The results showed that the temperature, the contact time with thesolution and the concentration all are important factors to reach a proper disinfection, but the resultsalso showed that the amount of bacteria in the solution also is an aspect to take into considerationwhen treating wastewater. Finally, the considerations of disinfection of the wastewater with sodium hypochlorite is discussed.The point of addition of the chlorine was concluded to best be directly after the last chemicaltreatment step. When analysing if the disinfection would be possible, the disinfection was from theresults possible, but it was noticed that the results fluctuated a lot. The most probable reason why isbecause of the water quality. The water quality in general fluctuates regularly throughout the day, aswell as in between days of the week. Therefore throughout the disinfection process, the additions ofchlorine would need to be depending on several parameters, making the disinfection difficult toimplement. One solution to this could be to add a lot of chlorine to the bulk water at all times, but itwould cost too much if treating the water for a longer time, as well as it would be a higher risk to theenvironment. A solution to this problem could be to possibly neutralize the water before it is releasedas well, however when analyzing the cost of the ascorbic acid that was used as neutralization in thisproject, the cost to neutralize the water completely would be too high. Lastly it was discussed that theonly time disinfection of the wastewater would give any desirable results, is if the specific organismsthat are being sought out to be treated are bacteria or some viruses. If the particular organism that iswished to be treated is parasites, the disinfection with chlorine would not work.
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BERGSTRAND, SUSANNE. "A study on the effects on a wastewater treatment plant when recovering the heat from the wastewater." Thesis, KTH, Skolan för industriell teknik och management (ITM), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-287374.
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source of thermal energy. Wastewater as a source of energy has gotten more attention in recent times, as the Sustainable Development Goals in combination with local challenges encourage new technical solutions that can replace old and outdated technology. By installing a heat exchanger to recover the heat, it can be used locally to heat buildings as well as urban areas. The technology and the opportunity to recover and use the energy is a way to operate in a circular way. Still, the infrastructure systems of water, wastewater, and thermal energy are intertwined, creating a complex and balanced environment where several actors representing their own interest and service to a community and urban area. Some actors may be the municipality handling the wastewater, real estate, and owner of buildings or the district heating company. This complexity in the urban area where several actors are involved with their own goal and all using the infrastructure surrounding water and wastewater in different ways, creates challenges. The users want to get rid of the wastewater and possibly recover heat from the wastewater, while the producer is responsible for the treatment plant and treatment, and is dependent on the wastewater reaching the plant with the highest temperature possible, and thereby not disrupting the process by a decrease in temperature created by the upstream heat recovery systems. The purpose of this study is to examine how the wastewater treatment plant react and is affected if the influent wastewater temperature decreases as a consequence of heat recovery from the wastewater, as the removal of nutrients in the treatment plant are chemical and biological processes which are depending on the temperature. By examining operational data from Henriksdals wastewater treatment plant and a model simulating the removal of nutrients in activated sludge, some light can be shed on how the processes of the treatment plant react to colder incoming wastewater. The legal framework and regulations around the wastewater treatment will also be examined due to the complexity of these systems, which is often overlooked.<br>Under markytan i urbana miljöer flödar avloppsvatten i avloppsnätet från byggnader till avloppsreningsverk. Avloppsvattnet innehåller stora mängder termisk energi och är därmed en outnyttjad energikälla i form av värme. Denna energikälla och konceptet värmeåtervinning ur avloppsvatten har fått mer och mer uppmärksamhet från både den akademiska världen och från olika fastighetsägare under senaste tiden, då man sett potentialen med ett utvinna värme ur avloppsvatten. Att installera en värmeväxlare för ett sådant ändamål kan antingen göras lokalt i anslutningen till en byggnad eller i större skala i en stadsmiljö. Tekniken och möjligheten att återvinna värmen från avloppet är ett sätt att identifiera var resurser kan användas cirkulärt. Dock är infrastrukturen kring vatten och avlopp och fjärrvärme sammanläkande, vilket skapar komplexa relationer mellan de olika aktörerna inom energibolag, fastighetsägare samt kommunerna som renar avloppsvattnet. I en stadsmiljö uppstår en komplexitet när flera olika aktörer använder infrastrukturen kring vatten och avlopp. Användarna använder infrastrukturen för att göra sig av med avloppsvatten och eventuellt utvinna värme ur det, medan producenterna är ansvariga för avloppsreningsverket och reningsprocessen. Producenterna är beroende av att avloppsvattnet kommer fram till avloppsreningsverket med högsta möjliga temperatur eftersom processerna på reningsverket kan påverkas av en lägre inkommande temperatur av avloppsvattnet. Syftet med denna studie är att undersöka hur avloppsreningsverket påverkas om det inkommande avloppsvattnets temperatur sänks som följd av användandet av värmeutvinning ur avloppsvattnet, givet att de kemiska och biologiska reningsprocesserna av näringsämnena kväve och fosfor är temperaturberoende. Med driftdata från Henriksdals avloppsreningsverk i Stockholm som grund, kombinerat med modellering av reningen av fosfor och kväve i simulatorn JASS, Java Activated Sludge Simulator, kan denna uppsats bidra till en bättre förståelse för hur avloppsreningsverket påverkas av kallare inkommande avloppsvatten. Den lagstiftning och riktlinjer som styr avloppsreningsverket som bidrar till systemens komplexitet och som ofta förbises har även undersökts. Driftdata och modellering i denna studie indikerar särskilt en påverkan av kvävereningen vid lägre temperatur av det inkommande avloppsvattnet. Detta beror sannolikt på att kvävereningen sker huvudsakligen genom biologiska processer med bakterier och mikroorganismer. Detta resulterat i att en minimal mängd värme kan återvinnas under vintern och kallare perioder under året för att inte påverka reningen av avloppsvattnet. Samtidigt är den befintliga infrastrukturen kring vatten och avlopp byggda för årtionden sen och är i stort behov av renovering. Renovering av befintliga rör skulle kunna minska mängden tillskottsvatten reningsverket hanterar idag. De huvudsakliga resultaten och slutsatsen av detta examensarbete är att systemen och infrastrukturen kring energi och värme samt vatten och avlopp hänger ihop och påverkar varandra i en stadsmiljö där fjärrvärme används. Detta blir särskilt tydligt i ett system där värme utvinns uppströms från reningsverket. Baserat på analys av driftdata från Henriksdals reningsverk i Stockholm samt modellering av den biologiska reningen finns tydliga tecken på att den biologiska reningen av kväve och fosfor skulle påverkas om den inkommande temperaturen skulle minska till följd av värmeutvinning ur avloppsvattnet. Baserat på denna studie med driftdata från Henriksdals reningsverk, avtar den biologiska reningen av kväve nästan linjärt med avtagande temperatur på avloppsvattnet, då tillväxten av mikroorganismer i slammet minskar och avstannar med kallare temperatur. Mikroorganismernas roll i slammet är viktig då det är de som utför omvandlingen av ammoniumkväve till nitratkväve och sedan nitratkväve till kvävgas. Reningsgraden av mikroorganismerna noteras vara nästan linjär med varmare temperatur, men endast till ca 30°C då reningen blir mer konstant.
36
Qiu, Yong. "STUDY ON TREATMENT TECHNOLOGIES FOR PERFLUOROCHEMICALS IN WASTEWATER." Doctoral thesis, 京都大学 (Kyoto University), 2007. http://hdl.handle.net/2433/44143.
Full textAbstract:
学位授与年月日: 2007-07-23 ; 学位の種類: 新制・課程博士 ; 学位記番号: 工博第2837号<br>Perfluorochemicals (PFCs) were produced by industries and consumed “safely” as surfactants, repellents, additives, fire-fighting foams, polymer emulsifiers and insecticides for almost fifty years. However they are now considered as persistent, bioaccumulated and toxic (PBT) chemicals, and ubiquitously distributed in waster, air, human body and biota. Although some efforts were contributed to reduce PFCs in environment, such as development of alternatives and recycling processes, huge amount of persisted PFCs have already been discharged in environment and accumulated in biota including humans. In some industrialized areas, such as Yodo river basin in Japan, water environment and human blood were polluted by some PFCs, and thus reduction and control of PFCs were urgently required for the purpose of environmental safety and human health in these areas. Unfortunately, some studies implied that current water and wastewater treatment processes seemed ineffective to remove PFCs in trace levels. Therefore, this study will try to develop some proper technologies to treat trace level of PFCs in wastewater. In order to achieve this main objective, several works have been accomplished as follows. Current available literature has been reviewed to obtain a solid background for this study. Basic information of PFCs was summarized in physiochemical properties, PBT properties, productions and applications, regulations and etc.. Analytical methods for PFCs, especially of LC-ESI-MS/MS, were reviewed including pretreatment processes in diverse matrices, which derived objectives of chapter III. Distributions and behavior of PFCs were briefly discussed in water environments, biota sphere and human bloods. Available control strategies were shown in detail about alternatives, industrial recycling processes, and newly developed treatment processes. Current wastewater treatment processes showed inefficient removal for some PFCs, deriving objectives of chapter IV on the PFC behavior in treatment process. Newly developed treatment technologies seemed able to decompose PFCs completely but unsuitable for application in WWTP. Therefore, granular activated carbon (GAC) adsorption and ultra violet (UV) photolysis were developed in chapter V and VI as removal and degradation processes respectively. Fifteen kinds of PFCs were included in this study, consisting of twelve kinds of perfluorocarboxylic acids (PFCAs) with 4~18 carbons and three kinds of perfluoroalkyl sulfonates (PFASs) with 4~8 carbons. An integral procedure was developed in chapter III to pretreat wastewater samples. LC-ESI-MS/MS was applied to quantify all PFCs in trace level. Pretreatment methods were optimized between C18 and WAX-SPE processes for aqueous samples, and between IPE, AD-WAX and ASE-WAX processes for particulate samples. Standard spiking experiments were regularly conducted for each wastewater sample to calculate recovery rate and control analytical quality. As the result, WAX-SPE showed better performance on samples with very high organics concentrations, and C18-SPE performed better for long-chained PFCs. ASE-WAX was proposed as the optimum method to pretreat particulate samples because of the simple and time saving operations. 9H-PFNA was used as internal standard to estimate matrix effect in wastewater. Behavior of PFCs in a municipal WWTP has been studied in chapter IV by periodical surveys for six times in half a year. All PFCs used in this study were detected in WWTP influent and effluent. According to their carbon chain lengths, all PFCs can be classified into “Medium”, “Long” and “Short” patterns to simplify behavior analysis. PFCs in same pattern showed similar properties and behavior in wastewater treatment facilities. Very high concentrations of PFCs existed in WWTP influent, indicating some point sources of industrial discharge in this area. “Medium” PFCs, such as PFOA(8), PFNA(9) and PFOS(8), were primary contaminants in the WWTP and poorly removed by overall process. Performances of individual facilities were estimated for removal of each PFC. Primary clarification and secondary clarification were helpful to remove all PFCs in both aqueous phase and particulate phase. “Medium” PFCs in aqueous phase were increased after activated sludge process, but other PFCs can be effectively removed. Ozone seemed ineffective to decompose PFCs because of the strong stability of PFC molecules. Sand filtration and biological activated carbon (BAC) filtration in this WWTP can not remove PFCs effectively too, which required further studies. Performances of combined processes were estimated by integrating individual facilities along the wastewater flow. Activated sludge process coupled with clarifiers showed satisfied removal of most PFCs in the investigated WWTP except “Medium” PFCs. Adsorption characteristics of PFCs onto GAC have been studied by batch experiments in chapter V. Freundlich equation and homogenous surface diffusion model (HSDM) were applied to interpret experimental data. Isothermal and kinetics experiments implied that PFC adsorption on GAC was directly related with their carbon chain lengths. By ascendant carbon chain length, adsorption capacity for specific PFC was increased, and diffusion coefficient (Ds) was decreased. Ds of GAC adsorption was also decreased gradually in smaller GAC diameters. Coexisted natural organic matters (NOMs) reduced adsorption capacities by mechanism of competition and carbon fouling. Carbon fouling was found reducing adsorption capacity much more intensively than competition by organics. Acidic bulk solution was slightly helpful for adsorption of PFCs. However adsorption velocity or kinetics was not affected by NOM and pH significantly. GAC from Wako Company showed the best performance among four kinds of GACs, and Filtra 400 from Calgon Company was considered more suitable to removal all PFCs among the commercial GACs. Preliminary RSSCT and SBA results implied that background organics broke through fixed GAC bed much earlier than trace level of PFCs. Medium-chained PFCs can be effectively removed by fixed bed filtration without concerning biological processes. Direct photolysis process has been developed in chapter VI to decompose PFCAs in river water. Irradiation at UV254 nm and UV254+185 nm can both degrade PFCAs. Stepwise decomposition mechanism of PFCAs was confirmed by mass spectra analysis, and consecutive kinetics was proposed to simulate experimental data. PFASs can also be degraded by UV254+185 photolysis, although the products have not been identified yet. Coexisted NOMs reduced performance of UV photolysis for PFCAs by competition for UV photons. Sample volume or irradiation intensity showed significant influence on degradation of PFCAs. Local river water polluted by PFOA can be cleaned up by UV254+185 photolysis effectively. Ozone-related processes were also studied but ineffective to degrade PFC molecules. However, PFCs could be removed in aeration flow by another mechanism.<br>京都大学<br>0048<br>新制・課程博士<br>博士(工学)<br>甲第13340号<br>工博第2837号<br>新制||工||1417(附属図書館)<br>UT51-2007-M963<br>京都大学大学院工学研究科都市環境工学専攻<br>(主査)教授 田中 宏明, 教授 藤井 滋穂, 教授 伊藤 禎彦<br>学位規則第4条第1項該当<br>Doctor of Engineering<br>Kyoto University<br>DFAM
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Caglia, Stefania. "Nitrogen Removal in the Pilot Plant ITEST (Increased Technology in Sewage Treatment)." Thesis, KTH, Mark- och vattenteknik (flyttat 20130630), 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-171846.
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Regions with a cold winter, as in the Baltic countries, have a problem to meet the nitrogen requirement in the Urban Wastewater Treatment Directive 98/15/EC. Especially in the winter season, the temperature of the influent wastewater could arrive also below 10°C and this delays the biological processes that takes place in the wastewater treatment. With the decrease of the temperature, the efficiency of nitrogen removal in the system decreases and leads to a high nitrogen loading in the effluent. The ITEST (Increased Technology and Efficiency in Sewage Treatment) project situated in Hammarby Sjöstadsverk in Stockholm has as its main aim to enhance nitrogen removal, thereby increasing the temperature in the incoming wastewater. The pilot plant ITEST is comprised of two treatment lines, one works with natural temperature influent and the other works at the temperature of 20 °C. In order to warm the incoming water a heating system, using waste heat, is used, leading to save energy. The two test lines were compared analyzing different parameters from January to May 2013. Total nitrogen, nitrate-nitrogen and ammonium-nitrogen concentrations were measured in the incoming water and in the effluent from the two treatment lines. Hence, the efficiency of the nitrogen removal was compared between the reference and the temperature line. In the period where the system was well functioning, the results show a nitrogen efficiency with a maximum of 92 % of removal of total nitrogen for the temperature line compared to only 65 % for the reference line. In the period where the system did not have any troubles the total nitrogen is under 10 mg/l, which is the limit of total nitrogen discharges specified in the Directive. Instead, for the sludge volume and the suspended solids any particular difference can be noticed from the two lines of treatment. In conclusion, in the temperature line can be noticed a great efficiency in nitrogen removal compared to the reference line.
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Chang, Jiang. "A General Investigation of Shanghai Sewerage Treatment System." Thesis, Högskolan i Halmstad, Sektionen för ekonomi och teknik (SET), 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-15662.
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As a modern metropolis, Shanghai has a registered population of 18.8 million in 2011, and the permanent population has been more than 20 million. As a result, Shanghai produces more than 6.3 million cubic meters of sewage per day which is considered as a massive test for Shanghai’s sewerage treatment system. Given the high proportion of time spent on the literature review, this study has investigated how the whole system works in Shanghai. To do this, Shanghai sewerage systems were divided into two parts – the drainage system and the sewage treatment system, and they were introduced respectively following the track of history development process. It was done by combining previously published theses, study reports, governmental documents, overt information by companies and news reports. It showed that, in 2009, Shanghai’s government established a basic formation of six centralized sewage treatment systems in co-existence with 52 sewage treatment plants. In the same year, the sewage treatment rate reached 78.9%, which can be considered a leap compared with the 62.8% figure in 2003. In spite of that, the gap between sewage treatment in Shanghai and that in developed countries still exists. By comparing Shanghai Bai Longgang sewage treatment plant with Halmstad Västra Stranden's waste water treatment plant, it can be concluded that the gap was embodied in differences of inflow condition, relative low discharge standards and poor treatment capability.
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WAHID, MARFIAH BINTI AB. "OCCURRENCE AND REDUCTION OF PATHOGENS IN WASTEWATER TREATMENT AND CONSIDERATION FOR WASTEWATER RECLAMATION AND REUSE." 京都大学 (Kyoto University), 2011. http://hdl.handle.net/2433/151968.
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Sandu, Simonel Ioan. "Evaluation of ozone treatment, pilot-scale wastewater treatment plant, and nitrogen budget for Blue Ridge Aquaculture." Diss., Virginia Tech, 2003. http://hdl.handle.net/10919/11271.
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Sustainable tilapia production at Blue Ridge Aquaculture (BRA) is constrained by availability of high quality replacement water. I developed a pilot-scale wastewater treatment system to treat and reuse effluent presently discharged. An initial study was conducted to determine the response of the BRA waste stream to ozone application. Dosages of 6.9, 4.8 and 2.4 g O3 were applied for 30 minutes to 35 L of settled effluent. Optimum ozone dosage and reaction time, ozone transfer efficiency, ozone yield coefficient, degree of pollutant removal, and other ozone and water quality parameters were determined. Most results suggested that the maximum process feasibility limit for ozone contact time was approximately 9 minutes at an applied ozone concentration of 23g/m3 (6.9 g O3 dose). Formation of foam increased solids and COD removal up to three times. Poor removal or accumulation of DOC and TAN was observed, indicating the need for biological treatment following ozonation.
Next, I evaluated a pilot station treatment train including sedimentation, microscreen filtration, fluidized bed denitrification, ozonation, aerobic biological oxidation in a trickling filter, and jar-test chemical flocculation. Significant improvements were found regarding solids, COD, cBOD5, NO3--N, TKN, and turbidity. Removal of foam after ozonation improved ozonation efficacy and pollutant removal.
A nitrogen budget for the BRA facility was derived, indicating that 35% of the nitrogen applied in feed was assimilated in fish. I evaluated the possible impact of residual inorganic nitrogen forms from treated effluent upon fish in the recirculating systems. I found that less than 1% of the TAN produced would return the recovered stream, and that the existing biological contactors can remove it. Evaluation of TAN fate indicated that 84% was oxidized in biofilters, 14% was oxidized by passive nitrification, and 1% was removed by water exchange. For NO3-N, I determined that 56% was removed by passive denitrification and 44% by daily water exchange.
The pilot station design was effective for removing organics and nutrients, and can serve as the basis for scale-up for treating and reusing the entire BRA effluent stream.<br>Ph. D.
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Bowyer, Jocelyn Cathryn. "The ecological significance of dissolved organic nitrogen from wastewater treatment plant effluents /." [St. Lucia, Qld.], 2004. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe18524.pdf.
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Sumi, Yukiyasu 1973. "High-level phosphorus removal in a small municipal wastewater treatment plant (WWTP)." Thesis, Massachusetts Institute of Technology, 1999. http://hdl.handle.net/1721.1/80174.
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Narasimhan, Gautam G. (Gautam Ganti) 1976. "Dynamic data management and modeling in a lagoon based wastewater treatment plant." Thesis, Massachusetts Institute of Technology, 2000. http://hdl.handle.net/1721.1/80958.
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Thesis (M.Eng.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2000.<br>Includes bibliographical references (leaves 72-73).<br>by Gautam G. Narasimhan.<br>M.Eng.
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Hill, Gemma. "Investigating wastewater treatment plant impact on antibiotic resistance within UK river systems." Thesis, University of Warwick, 2016. http://wrap.warwick.ac.uk/88822/.
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Antimicrobial resistance (AMR) presents one of the most important threats to human health of the 21st century. The recent report on AMR predicted that by 2050 10 million deaths a year will be directly attributable to AMR bacterial infections. The dissemination of antibiotic resistance genes (ARG) in to the environment has previously been highlighted as an important route of transmission and was investigated in the current study. Wastewater treatment plants (WWTP) have been highlighted to contribute to ARG pollution of rivers focusing on effluent impact on receiving water bodies. In this study the aim was to further investigate the effects of WWTP effluent on the receiving river, but also investigate the release of raw sewage resulting from combined sewer overflow (CSO) events on the receiving river. This study found that sediment samples carried a higher abundance of all ARG and therefore present a greater risk compared to water and that CSO spills are important in the spread of ARG likely contributing more substantially to the environmental spread of resistance than continuous release of treated wastewater. In addition, the present study aimed to investigate the genetic potential of viable, potentially pathogenic Escherichia coli isolates from the river sediment to determine whether these human opportunistic pathogens carried the genetic capacity to spread resistance and cause disease. E. coli strains were shown to carry extensive resistance to many clinically relevant antibiotics, metals and biocides as well as carrying vast virulence-associated genes. This study identified ST940 as an important sequence type (ST) in the dissemination of the ESBL blaCTX-M-15 gene and suggests further work to investigate the importance of this ST type in the transmission of this clinically important ARG. The work presented here supports previous studies demonstrating extensive environmental ARG dissemination in rivers as a direct result of WWTP impacts and further highlights rivers as an important reservoir of ARG and antibiotic resistant bacteria (ARB). The discovery of clinically important viable E. coli isolates in sediment suggests more rigorous methods of wastewater treatment, specifically a reduction in the number of CSO release events, must be employed if further dissemination of ARB is to be prevented.
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Paredez, Jose Miguel. "Coal-fired power plant flue gas desulfurization wastewater treatment using constructed wetlands." Thesis, Kansas State University, 2014. http://hdl.handle.net/2097/18255.
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Master of Science<br>Department of Civil Engineering<br>Natalie Mladenov<br>In the United States approximately 37% of the 4 trillion kWh of electricity is generated annually by combusting coal (USEPA, 2013). The abundance of coal, ease of storage, and transportation makes it affordable at a global scale (Ghose, 2009). However, the flue gas produced by combusting coal affects human health and the environment (USEPA, 2013). To comply with federal regulations coal-fired power plants have been implementing sulfur dioxide scrubbing systems such as flue gas desulfurization (FGD) systems (Alvarez-Ayuso et al., 2006). Although FGD systems have proven to reduce atmospheric emissions they create wastewater containing harmful pollutants. Constructed wetlands are increasingly being employed for the removal of these toxic trace elements from FGD wastewater.
In this study the effectiveness of using a constructed wetland treatment system was explored as a possible remediation technology to treat FGD wastewater from a coal-fired power plant in Kansas. To simulate constructed wetlands, a continuous flow-through column experiment was conducted with undiluted FGD wastewater and surface sediment from a power plant in Kansas. To optimize the performance of a CWTS the following hypotheses were tested: 1) decreasing the flow rate improves the performance of the treatment wetlands due to an increase in reaction time, 2) the introduction of microbial cultures (inoculum) will increase the retention capacity of the columns since constructed wetlands improve water quality through biological process, 3) the introduction of a labile carbon source will improve the retention capacity of the columns since microorganisms require an electron donor to perform life functions such as cell maintenance and synthesis. Although the FGD wastewater collected possessed a negligible concentration of arsenic, the mobilization of arsenic has been observed in reducing
sediments of wetland environments. Therefore, constructed wetlands may also represent an environment where the mobilization of arsenic is possible. This led us to test the following hypothesis: 4) Reducing environments will cause arsenic desorption and dissolution causing the mobilization of arsenic.
As far as removal of the constituents of concern (arsenic, selenium, nitrate, and sulfate) in the column experiments, only sulfate removal increased as a result of decreasing the flow rate by half (1/2Q). In addition, sulfate-S exhibited greater removal as a result of adding organic carbon to the FGD solution when compared to the control (at 1/2Q). Moderate selenium removal was observed; over 60% of selenium in the influent was found to accumulate in the soil.
By contrast, arsenic concentrations increased in the effluent of the 1/2Q columns, most likely by dissolution and release of sorbed arsenic. When compared to the control (at 1/2Q), arsenic dissolution decreased as a result of adding inoculum to the columns. Dissolved arsenic concentrations in the effluent of columns with FGD solution amended with organic carbon reached 168 mg/L. These results suggest that native Kansas soils placed in a constructed wetland configuration and amended with labile carbon do possess an environment where the mobilization of arsenic is possible.
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Rosendahl, Sara. "Modelling control strategies for chemical phosphorus removal at Tivoli wastewater treatment plant." Thesis, Uppsala universitet, Institutionen för geovetenskaper, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-453546.
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Wastewater compose an environmental risk as it contains high levels of nutrients, including phosphorus. Wastewater treatment plants (WWTPs) reduce phosphorus by using coagulants that precipitate soluble phosphate into metal phosphate, which is separated by settling. Coagulant flow is regulated by a control strategy, typically feedforward or feedback control. Feedforward is based on incoming wastewater disturbances whereas feedback control uses outgoing process values. Incoming phosphate is hard to measure and can be estimated using soft sensors. Modelling control strategies can help decide which strategy that is most suitable. Models describing phosphorus removal are Activated Sludge Model, ASM2d, and primary clarifier model. ASM2d models phosphorus precipitation and the primary clarifier model settling of particles. Tivoli WWTP faces challenges to reach effluent requirements of phosphorus. The wastewater flows through an equalisation tank, Regnbågen, before being pumped to Tivoli. Particulate matter settles in Regnbågen, which is removed by reducing the water level in Regnbågen. This rapidly increases incoming particulate load to Tivoli.Tivoli’s current control strategy is feedforward proportional to suspended solids. It is suspected, that this strategy overdose coagulant during the emptying of Regnbågen. The purpose of this thesis was to find the optimal control strategy for phosphorus precipitation at Tivoli WWTP, by using a model-based approach. Control strategies modelled are; feedforward, feedback and these two control strategies combined. Additional issues resolved are 1) calibration of a model that predicts the effect of chemical dosage on effluent phosphorus concentration from the primary clarifier, 2) calibrationof a soft sensor, 3) determination of which control strategy that is most suitable. ASM2d and a primary clarifier model were used to create a model describing chemical phosphorus removal. The calibration matches measured phosphate concentration, but underestimate peaks. The primary clarifier model was calibrated by minimising load differences for phosphate and total suspended solids, and was calibrated satisfyingly. A simplified soft sensor was constructed, described by a linear relationship between phosphate and pH. Three disturbances for feedforward control were analysed; measured phosphate, the soft sensors estimation of phosphate and Tivoli’s current controlstrategy. The optimal control strategy was found through a multi-criteria analysis. The optimal control strategy is the combined control strategy, when feedforward is proportional to incoming measured phosphate. The performance of all analysed feedforward disturbances were significantly improved when combined with feedback control. Furthermore, consequential errors are distinct when the soft sensor miss-predictincoming phosphate concentration. If the phosphate concentration cannot be correctly measured/estimated, feedback control alone has the best performance.
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Stern, Zachary Elfonte. "Reducing combined sewage overflows : the essentials of a sustainable stormwater management plan." Thesis, 2011. http://hdl.handle.net/2152/ETD-UT-2011-05-3018.
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This report examined efforts to manage combined sewage overflows and create effective stormwater management plans. To provide background on the issue, a brief history of sewage management was provided, along with the legal history regarding water quality, sewage and CSOs, effects of CSOs and current green infrastructure methods for dealing with CSOs. The report then compared the efforts of three cities--Portland, Oregon; Philadelphia, PA; and Chicago, IL--to improve water quality and manage CSOs and stormwater. From the examination of the efforts of these cities the author derived a list of ten recommended elements for a CSO/stormwater management plan. These recommended elements were then used to evaluate New York City's recently released sustainable stormwater management plan and its prospects for success.<br>text
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Mhlanga, Farai Tafangenyasha. "Modelling of the Marianridge wastewater treatment plant." Thesis, 2008. http://hdl.handle.net/10413/897.
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One of the consequences of the social and economIc change due to industrialisation is the generation of industrial wastewater which requires treatment before being released into the natural aquatic environment. The municipality has wastewater treatment plants which were initially designed for the treatment of domestic wastewater. The presence of industrial wastewater in these treatment plants introduces various difficulties in the treatment process due to the complex and varying nature of the industrial wastewater. A means needs to be developed, that will allow the municipality to evaluate if a wastewater treatment plant can adequately treat a particular composition or type of wastewater to a quality suitable for release to the environment. Developing a simulation model for a wastewater treatment plant and calibrating it against plant operating data will allow the response of the wastewater treatment plant to a particular wastewater to be evaluated. In this study a model for the Mariamidge Wastewater Treatment Plant is developed in the WEST (Worldwide Engine for Simulation, Training and Automation) software package. The sources of data for modelling were laboratory experiments, historical data from the municipal laboratory and modelling of experiments. Dynamic input files representing the properties of the influent wastewater were generated by characterising the influent wastewater through the use of batch respirometric tests and flocculation filtration on composite samples of wastewater. Kinetic and stoichiometric coefficients of the model were determined from batch respirometric tests on wastewater and activated sludge, and simulation of the batch respirometric experiment. To make the model plant-specific it is calibrated against plant operating data. Influent characterisation and reliable ASM3 model parameters were determined from the respirometric batch test and modelling of experiments. The resulting plant model was able to closely predict the trends of the effluent COD concentration in the plant. Hence it was concluded that the use of laboratory experiments, historical data from the municipal laboratory and modelling of experiments in order to generate information for the modelling of wastewater treatment plants makes up a methodology which can be adopted and improved by additional experiments.<br>Thesis (M.Sc.Eng.)-University of KwaZulu-Natal, Durban, 2008.
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Wu, Yu-chen, and 吳宇蓁. "Effects of CMP wastewater on treatment efficiency and operation cost in industrial wastewater treatment plant." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/61983604224515926923.
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碩士<br>國立中央大學<br>環境工程研究所碩士在職專班<br>97<br>Abstract
Since the technology of product process continuously is improved some of the specific pollutants potentially cause serious problems on operation and treatment of the wastewater treatment plant in the industrial parks. Further, these pollutants could increase the cost of operation and maintainance for the wastewater treatment plant. Thus, it is important to set up reasonable fee criteria for these specific wastewaters. The purpose of this study is to evaluate the effects of chemical mechanical planarization (CMP) wastewater on the removal efficiency of chemical treatment process in a wastewater treatment plant. Moreover, characteristics of the wastewater including high turbidity, low suspended solid (SS) and micro-size particles, which result in interference on the floc formation in the coagulation process, are also investigated.
The results indicated pH value of the wastewater reaches limit level that generated the highest effect on the floc formation. It is suggested that the optimum coagulant (aluminum sulfate, Al2(SO4)3) dose is 350 ppm when the pH level is adjusted to 10. However, without the CMP wastewater, the optimum coagulant dose for the general wastewater decreases to 50 ppm. The optimum dose for the simulated synthetic water is 100 ppm. When the raw wastewater mixed with the CMP wastewater was filtrated using the 0.45μm and 0.2μm filters, the optimum dose of the mixed wastewater is 50 ppm that is equal to general wastewater. Moreover, if the wastewaters were classified based on the pollution sources, the added amount of aluminum sulfate in CMP wastewater is two times than that of in general water with the similar coagulation efficiency.
The fee criteria about wastewater discharged into wastewater treatment system in the industrial park is performed based on the concentration of SS through 1μm filter. In this case, the measured SS concentration cannot reflect on the pollution level for the CMP wastewater because some of the SS in the CMP wastewater can penetrate the 1μm filter. We suggested that the 0.45μm filter is used to measure SS concentration of the CMP wastewater which is a proper way for the cost assessment. Moreover, the increase in the fee according to the SS concentration is approximate 40%, which reduce the loading of operation cost.
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Kai, Lung Cheng, and 鄭凱隆. "Energy saving evaluation of A2O system in a domestic wastewater treatment plant-Case study of Dashu wastewater treatment plant." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/72448017895850386667.
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碩士<br>國立屏東科技大學<br>環境工程與科學系所<br>99<br>Water is one of the most important natural resources mankind needs, while the electric power is the base of industrial development. Both of the two also provide what people need in daily life and necessaries for mankind. Therefore, this research combined the author’s job and used the operation of Dashu wastewater treatment plant as example to discuss the performance promotion and measure improvement of energy conservation. Currently the influent flowrate is only 23% of the original design, furthermore, the discharge does not have to meet the nutrient requirements of nitrogen and phosphorus. It is expected that, through the adjustment of unit operation and process, performance and be enhanced and energy can be saved.
In this study, biological treatment units are the focus of operation adjustment, which contributes about 37% of power consumption of the whole plant. The original design of A2O processes are adjusted to the activated sludge system for energy saving. In consideration of the consistency and stability of the evaluation, data collections are arranged at the same period of the year, i.e., operation of A2O system mode from June to November, 2009 and operation of activated sludge mode from June to November, 2010). In this investigation, with no change in the treatment processes, the activated sludge was used to operate the system and water qualities were sampled. The water quality and energy consumption were studied before and after the adjustment of biological treatment process.
From this research it was found that 22% of electric power cost was saved using the activated sludge process. Meanwhile, in water quality, the effluents of BOD, COD, and SS are 6.1, 18.6, and 6.8 mg/L, respectively. There is no significant difference between the activated sludge treatment and A2O operations. However, in the concentrations of Total Nitrogen and Phosphorous, the average effluent concentrations are 12.68 and 1.307 mg/L, respectively. There is a slight increase in the activated sludge treatment than the A2O operation. Although the minute increases of Total N and P is extremely limited to the annual runoff of more than 8 billion cubic meters in the Kao-ping River, its long term impact upon the environment is still a concern.