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Черниш, Єлізавета Юріївна, Елизавета Юрьевна Черныш, and Yelyzaveta Yuriivna Chernysh. "The sewage sludge detoxification." Thesis, Сумський державний університет, 2013. http://essuir.sumdu.edu.ua/handle/123456789/33561.
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Recycling of organic sewage sludge today is an urgent problem in the whole territory of Ukraine, which requires a solution. At the most of the municipal wastewater treatment plants, unfortunately, current removal, treatment and recycling of sewage sludge are not properly resolved. At present, the general part of sewage sludge is not carried out. Because it contains toxic chemicals, mainly heavy metals (HM) within the industrial waste water coming into the city sewer system after insufficient treatment or without treatment. As a result, sewage sludge is sent to the sludge pit and storage sites, which are assigned to the large land area. Therefore the process of HM removing from sewage sludge is of paramount importance to allow using sewage sludge as an organic fertilizer in agriculture.
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Heredia, Salgado Mario Alejandro. "Sewage sludge drying and combustion." Master's thesis, Universidade de Aveiro, 2014. http://hdl.handle.net/10773/13409.
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Mestrado em Sistemas Energéticos SustentáveisA brief review of the paper pulp production process in order to understand the origin of the sewage sludge was performed. Then a general revision of the current treatment options for this type of waste was addressed. The thermal treatment by combustion was focused and a review of the state of the art of this process was performed. The high moisture content of sludge was identified as a major concern. Thus a revision of the state of the art regarding thermal drying of sewage sludge was performed. The drying behavior of sewage sludge from the pulp and paper industry was evaluated by experiment in a drying tunnel. Strong shrinkage, cracks and a weak crust phenomenon were identified. A drying kinetic model was developed by the use of Artificial Neural Networks achieving a high Pearson correlation coefficient in the validation tests. Additionally a theoretical assessment of the co-combustion process was performed having into account a 50 MWth combustion facility. The inclusion of different portions of sewage sludge in a fuel mixture and the influence of the sludge moisture content was studied. It was found that burning sewage sludge with more than 50 wt% moisture content is not possible. Furthermore the inclusion of sewage sludge in a biomass fuel mixture causes an increase in the fuel consumption, solids production and heat losses in the flue gas. Based on general thermodynamic considerations the thermal power of a sludge dryer was calculated. The use of waste heat to supply the energy needs of the drying process was addressed by the waste heat availability estimation as sensible heat and latent heat at the stack of the facility. A set of combustion experiments were done in a pilot scale bubbling fluidized bed combustor to assess the combustion efficiency by monitoring the CO2, CO, H2O and O2 levels in conjunction with the temperature profile along the reactor height. Two different types of fuel samples were prepared. One composed by 100 wt% sewage sludge (fuel sample 1) and other composed by 50 wt% sewage sludge and 50 wt% residual forest biomass (particle size <1mm) (fuel sample 2). Low CO levels were onserved especially for the fuel sample 2 which indicates a very efficient combustion process. The CO emission level established by the Portuguese law for this type of reactor was never exceeded under typical operating conditions. The temperature profile along the reactor confirms that the combustion of the fuel samples prepared occurs mainly in the freeboard zone. It was not observed agglomeration problems and the fluidization conditions were kept constant during all the experimental tests. After the combustion experiments a considerable ashes quantity were found and its particle size distribution was estimated.
Foi realizada uma revisão sucinta do processo de produção de pasta de papel, a fim de compreender a origem da lama biológica. Uma revisão geral das opções atuais de tratamento para este tipo de resíduo foi abordada. O tratamento térmico por combustão foi focalizado e uma avaliação do estado da arte deste processo foi realizada. Foi verificado que o elevado teor de humidade da lama representa uma grande preocupação. Por tanto, realizou-se uma revisão do estado da arte em relação à secagem térmica das lamas. O comportamento da lama secundaria da indústria de pasta e papel foi estudado experimentalmente em um túnel de secagem. Foram observados os fenómenos de encolhimento e rachaduras além do fenomeno de crosta, embora este último não seja muito pronunciado. Foi desenvolvido um modelo de cinética de secagem com recurso ao uso de Redes Neurais Artificiais, sendo observado um elevado coeficiente de correlação nas experiências de validação. Foi realizada uma análise teórica ao processo de co-combustão de lama com biomassa florestal numa instalação de combustão de 50MWth. Estudou-se a inclusão de diferentes fracções de lama numa mistura de combustível contendo biomassa florestal, assim como também a influência do teor de humidade da lama. Verificou-se que a combustão de lamas biológicas com mais do que 50 wt% em teor de humidade não é possível. Além disso, a inclusão destas lamas na mistura de combustível provoca um aumento do consumo de combustível na instalação, da produção de sólidos e das perdas de calor no efluente gasoso da instalação. Com base em considerações termodinâmicas foi determinada a potência térmica de um secador de lamas. A utilização do calor residual para suprir as necessidades energéticas do processo de secagem foi abordada a través da estimativa da disponibilidade de calor residual na forma de calor sensível e calor latente no efluente gasoso da instalação de combustão. Foi realizado um conjunto de experiências de combustão de lamas e sua mistura com biomassa florestal num reactor de leito fluidizado borbulhante á escala piloto para avaliar a eficiência de combustão através da concentração de CO2, CO, O2 e H2O, em conjunto com o perfil de temperaturas ao longo do reactor. Foram utilizados dois tipos diferentes de amostras de combustível, uma composta por 100 wt% de lama biológica (combustível 1), e outra composta por 50 wt% de lama biológica e 50 wt% de biomassa florestal residual (tamanho de partícula <1mm) (combustível 2). Foram observados baixos níveis de CO no efluente gasoso, emparticular para a amostra de combustível 2, o qual indica um processo de combustão muito eficiente. Para condições de operação (temperatura e estequimetria) típicas, verificou-se que o limite de emissão de CO estabelecido pela lei Portuguesa para este tipo de fornalhas não foi excedido. O perfil de temperatura ao longo do reactor confirma que a combustão das amostras de combustível preparadas ocorre principalmente na zona do freeboard. Não foram verificados problemas de aglomeração e as condições de fluidização foram mantidas constantes durante todos os ensaios experimentais. Após os ensaios de combustão foi observada uma quantidade considerável de cinzas na fornalha, tendo sido avaliada a sua distribuição granulométrica.
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Chan, Lap-man. "Sludge management : oversea experience and application in Hong Kong /." [Hong Kong : University of Hong Kong], 1994. http://sunzi.lib.hku.hk/hkuto/record.jsp?B13813560.
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An, Kyoung Jin. "Reduction of excess sludge in an oxic-settling-anaerobic (OSA) system : a modified activated sludge process /." View abstract or full-text, 2004. http://library.ust.hk/cgi/db/thesis.pl?CIVL%202004%20AN.
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Thesis (Ph. D.)--Hong Kong University of Science and Technology, 2004.Includes bibliographical references (leaves 188-201). Also available in electronic version. Access restricted to campus users.
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Burke, Russell Armstrong. "Biological excess phosphorus removal in short sludge age activated sludge systems." Master's thesis, University of Cape Town, 1986. http://hdl.handle.net/11427/7582.
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Includes bibliography.The objective of this investigation was to test, at laboratory-scale, the behaviour of short sludge age biological excess P removal systems, to assess the response of the systems under non-nitrifying and nitrifying conditions, to determine the optimal system configuration(s) and operational parameters, and to check the settling characteristics of the mixed liquor produced in the systems. A secondary objective was to use the observed response data to test the predictive qualities of both the general activated sludge model of Dold, Ekama. and Marais (1985) and the semi-empirical biological excess P removal model of Wentzel, Dold, Ekama and Marais (1984). The objectives were fulfilled by operating a number of laboratory scale anaerobic/aerobic and anaerobic/anoxic/aerobic systems with varying sludge ages, anaerobic, anoxic and aerobic mass fractions, mixed liquor recycle ratios and COD loading rates.
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Nieto, Cebrián Antonio. "Emerging organic contaminants in sewage sludge." Doctoral thesis, Universitat Rovira i Virgili, 2010. http://hdl.handle.net/10803/9048.
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El objetivo de esta tesis es el desarrollo de métodos analíticos para la determinación de un grupo de contaminantes emergentes entre los cuales se incluyen los fármacos y los compuestos de cuidado personal en lodos de depuradora.Los métodos desarrollados se basan en la extracción presurizada con solventes (PLE) y, debido a la polaridad de estos contaminantes, la cromatografia de líquidos. Como técnicas de detección se han utilizado la espectrometría de masas (con quadrupolo y tiempo de vuelo como analizadores) y la espectrometría de masas en tandem (con triple quadrupolo como analizador) utilizando la interfase de electrospray.
A parte del desarrollo de los métodos para la determinación de fármacos, hormonas y compuestos de cuidado personal, se han analizado muestras de dos plantas de tratamiento de aguas residuales de la zona de Tarragona. Se han obtenido resultados de la presencia de estos compuestos en lodos de depuradora que hasta la fecha no existían sobre las muestras de esta zona.
The scope of this thesis is to develop analytical methods to determine a group of pharmaceuticals and personal care products included in the list of so called "emerging organic contaminants".
The methods are based on pressurized liquid extraction as extraction technique and due to the polarities of these contaminants, liquid chromatography was the selected separation technique. Because the low concentration of these contaminants in sewage sludge, sensitive and selective detection technique have to be used such as mass spectrometry (with quadruople or time of flight analyzers) and tandem mass spectrometry (with triple quadrupole analyzer) using in all cases the electrospray interface.
The methods developed have been used to monitor several groups of pharmaceuticals and personal care products from sewage sludge from two different sewage treatment plants. The samples have been collected in Tarragona, where no studies related to the control of these compounds have been done.
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Lafitte-Trouque, Sandrine. "Enhanced anaerobic digestion of sewage sludge." Thesis, University of Birmingham, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.369392.
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Brown, Stanley. "Heavy metal detoxification of sewage sludge." Thesis, University of Manchester, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.302700.
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Mess, Harold. "Sewage sludge disposal constraints and opportunities." Thesis, Aston University, 1985. http://publications.aston.ac.uk/15168/.
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Dursun, Derya. "Gel-like behavior of biosolids in conditioning and dewatering processes." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 260 p, 2007. http://proquest.umi.com/pqdweb?did=1362540141&sid=7&Fmt=2&clientId=8331&RQT=309&VName=PQD.
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Ng, Yue-hang. "Dewatering and treatment of sewage sludge before landfill /." Hong Kong : University of Hong Kong, 1995. http://sunzi.lib.hku.hk/hkuto/record.jsp?B14723232.
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Fong, Chun-yau. "Latest development in waterworks sludge treatment and disposal in Hong Kong /." [Hong Kong : University of Hong Kong], 1993. http://sunzi.lib.hku.hk/hkuto/record.jsp?B13498733.
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Walker, David Howey. "CFD Modelling of Sewage Sludge Vitrification Plant." Thesis, University of Canterbury. Chemical and Process Engineering, 2008. http://hdl.handle.net/10092/1717.
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This Technology in Industry Fellowship (TIF) funded Masters Project was structured around Computational Fluid Dynamics (CFD) modelling for Lemar Environmental Ltd (Lemar). This study is a component of a larger programme that is being undertaken by Lemar concerning the vitrification process. The modelling has built on an initial model developed by CSIRO for Lemar and has been carried out under the direction of Canterbury University. The modelling involved computer simulations and detailed comparisons of the gas flow for both high and low swirl vanes, in both the steady state and transient modes. The output of this activity; velocity profiles (tangential and axial), vorticity, as well as particle tracking (in steady state mode only) were compared to literature and evaluated for both scenarios. As the study was restricted to the gas flow in transient mode, no recommendations and extrapolated modifications to the burner geometry and plant equipment can be made as they have to be verified by the particle motion within the gas flow. The steady state particle simulations obtained through this project, did not provide sufficient evidence to conclude that particles attach to the outer wall and only demonstrated the influences that the high and low swirl had on the particles. Further investigations of transient particle tracking would provide an overall interpretation as to whether or not the dried sludge particles bounced or stuck to the viscous slag layer and a commentary as to their movement in the chamber. Lemar's strategic vitrification programme is still active and the resulting redesign process is nearing completion and modifications to the plant are expected to be finalised by January 2008. Following extensive testing by Lemar it is understood that they would be looking to seek venture capital in order to progress the project to the market. In order for the final stage of the sewage sludge vitrification plant project to commence, Lemar has been in consultation with subject matter experts in the field, as well as undertaking trials on the plant, computer modelling and research into both the technical and international marketing prospects for the combustion technology. The detailed analysis and research undertaken through the CFD modelling conducted for this Project, recommends that Lemar conducts further CFD modelling to investigate transient particle tracking before any plant or geometry modifications are proposed and undertaken in order to optimise the ash capture which is a key output of the vitrification process.
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Jing, Jung. "Bioavailability of cadmium in municipal sewage sludge /." The Ohio State University, 1990. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487683049375578.
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Samanya, Janat. "Increase of energy recovery from sewage sludge." Thesis, Aston University, 2013. http://publications.aston.ac.uk/20734/.
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The use of the pyrolysis process to obtain valuable products from biomass is amongst the technologies being investigated as a source for renewable energy. The pyrolysis process yields products such as biochar, bio-oil and non condensable gases. The main objective of this project is to increase energy recovery from sewage sludge by utilising the intermediate pyrolysis process. The intermediate pyrolysis has a residence time ranging from 5 to 10 minutes. The main product yields from sewage sludge pyrolysis are 50 wt% biochar, 40 wt% bio-oil and 10 wt% non condensable gases. The project was carried out on a pilot plant scale reactor with a load capacity of 20 kg/h. This enabled a high yield of biochar and bio-oil. The characterisation of the products indicated that the organic phase of the bio-oil had good fuel properties such as having high energy content of 39 MJ/kg, low acid number of 21.5, high flash point of 150 and viscosity of 35 cSt. An increase in pyrolysis experiments enabled large quantities of pyrolysis oil production. Co-pyrolysis of sewage sludge was carried out on laboratory scale with mixed wood, rapeseed and straw. It found that there was an increase in bio-oil quantity with rapeseed while co-pyrolysis with wood helped to mask the smell of the sludge pyrolysis oil. Engine test were successfully carried out in an old Lister engine with pyrolysis oil fractions of 30% and 50% blended with biodiesel. This indicates that these pyrolysis oil fractions can be used in similar engine types without any problems however long term effects in ordinary engines are unknown. An economic evaluation was carried out about the implementation of the intermediate pyrolysis process for electricity production in a CHP using the pyrolysis oil. The prices of electricity per kWh were found to be very high.
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Day, Arden, Rex Thompson, and Spencer Swingle. "Barley Grain Grown with Dried Sewage Sludge." College of Agriculture, University of Arizona (Tucson, AZ), 1987. http://hdl.handle.net/10150/203763.
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A four-year experiment, conducted at the Mesa Agricultural Center, studied the use of dried sewage sludge from the City of Phoenix as a source of plant nutrients in the commercial production of barley grain. The objective was to compare the effects of sewage sludge and commercial fertilizer on barley growth, grain yield, and quality. Three fertilizer treatments were used: (1) suggested rates of nitrogen (N), phosphorus (P), and potassium (K) in Arizona; (2) dried sewage sludge to supply plant-available N in amounts equal to the suggested rate; and (3) N, P, and K from inorganic fertilizers, in amounts equal to those in sewage sludge. Characteristics of barley growth, grain yield, and quality were similar for the three fertilizer treatments. Barley can use the fertilizer nutrients in dried sewage sludge to produce grain as effectively as it can utilize the fertilizer nutrients in inorganic fertilizer.
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Steffens, Marc Alexander. "Advanced process control for nutrient removal activated sludge processes /." [St. Lucia, Qld.], 1997. http://library.uq.edu.au/screens/steffens.html.
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Wan, Iat-meng. "Physical characterization of dewatered sewage sludge for landfilling /." Hong Kong : University of Hong Kong, 1998. http://sunzi.lib.hku.hk/hkuto/record.jsp?B20717921.
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Tshivhunge, Azwiedziswi Sylvia. "Enzymology of activated sewage sludge during anaerobic treatment of wastewaters : identification, characterisation, isolation and partial purification of proteases." Thesis, Rhodes University, 2001. http://hdl.handle.net/10962/d1004072.
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During anaerobic digestion bacteria inside the digester require a carbon source for their growth and metabolism, sewage sludge was used as a carbon source in this study. The COD content was used to measure the disappearance of the substrate. COD content was reduced by 48.3% and 49% in the methanogenic and sulphidogenic bioreactors, respectively, while sulphate concentration was reduced by 40%, producing 70mg/L of hydrogen sulphide as the end product over the first 5-7 days. Sulphate (which is used as a terminal electron acceptor of sulphur reducing bacteria) has little or no effect on the sulphidogenic and methanogenic proteases. Sulphite and sulphide (the intermediate and end product of sulphate reduction) increased protease activity by 20% and 40%-80%, respectively. Maximum protease activity occurred on day 21 in the methanogenic reactor and on day 9 in the sulphidogenic reactor. The absorbance, which indicates the level of amino acid increased to 2 and 9 for methanogenic and sulphidogenic bioreactors, respectively. Proteases that were active during anaerobic digestion were associated with the pellet (organic particulate matter) of the sewage. These enzymes have an optimum activity at pH 10 and at temperature of 50°C. The proteases that were active at pH 5 and 7, had optimum temperatures at 30°C and 60°C, respectively. Due to their association with organic particulate matter, these enzymes were stable at their optimum temperatures for at least five hours at their respective pH. Inhibition by PMSF, TPCK and 1.10-phenanthroline suggested that proteases inside the anaerobic digester are a mixture of cysteine, serine and metalloproteases. At pH 5, however, EDTA appeared to enhance protease activity by 368% (three-fold). Acetic acid decreased protease activity by 21%, while both propionic and butyric acid at 200 mg/L cause total inhibition of protease activity while these acids at higher pH (where they exist as their corresponding salts) exerted little effect. Copper, iron and zinc inhibited protease activity by 85% at pH 5 with concentrations ranging between 200 and 600 mg/L. On the other hand, nickel, showed an increase in protease activity of nearly 250%. At pH 7 and 10, copper had no effect on protease activity while iron, nickel and zinc inhibited these enzymes by 20-40%. Proteases at pH 7 were extracted from the pellet by sonication, releasing 50% of the total enzymes into the solution. The enzymes were precipitated by ammonium sulphate precipitation, and further purified by ion exchange chromatography and gel filtration. Ion exchange chromatography revealed that most of the enzymes that hydrolyse proteins are negatively charged while gel filtration showed that their molecular weight is approximately 500 kDa.
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Hung, Benjamin Kwok Man. "Evaluation of sludge-grown algae for rearing aquatic organisms." HKBU Institutional Repository, 1993. http://repository.hkbu.edu.hk/etd_ra/14.
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Mak, Keung-kan, and 麥強根. "Sludge management in Hong Kong." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1994. http://hub.hku.hk/bib/B31252953.
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Mann, C. M. "Salmonella regrowth potential of two sewage sludge products /." View thesis View thesis, 1997. http://library.uws.edu.au/adt-NUWS/public/adt-NUWS20030521.100917/index.html.
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Thesis (M.Sc. (Hons)) - University of Western Sydney, Hawkesbury."A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science (Hons.) (Environmental Science" --tp.
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Bhasin, Aditi. "Recovery of Phosphorus from Incineration of Sewage Sludge." Thesis, KTH, Skolan för kemivetenskap (CHE), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-214991.
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The primary source of phosphorus, phosphate rock, is a non-renewable resource which is expected to get exhausted in the next 50 – 100 years. Sewage sludge in Sweden constitutes 25% of the annual phosphorus in the country, making it a potentially significant source for phosphorus recovery. The aim of this project was to identify the potential for phosphorus recovery from incineration of dewatered and digested sewage sludge in Fortum Värme’s power plants in Stockholm. The study was limited to two boilers located at Bristaverket, Stockholm - boiler B1, a bio-fired fluidized bed boiler and boiler B2, a waste-fired grate incinerator. A theoretical analysis for boiler B1 showed that it is possible to reach a concentration of 4.6% phosphorus in fly ash if sludge and recycled wood fuel are mixed in the ratio 48:52. A test program was executed in boiler B2 to burn up to 12.5% sludge with a mixture of household waste and industrial waste. A total of 755 tons of sludge was used over a period of three weeks during the test in boiler B2. The test was successful in terms of combustion and emissions. There was no increase in the emissions of nitrogen oxides, sulphur dioxide and hydrochloric acid in the flue gas. Mercury emissions in the chimney increased with an increase in the share of sludge, nevertheless, the emission level was below the limit set by the Swedish Environmental Protection Agency. Decrease in the amount of unburnt materials in bottom ash and in the emission of carbon monoxide showed that the burning of fuel was more efficient with input of sludge. The maximum phosphorus concentration was 0.7% in both bottom ash and fly ash from boiler B2 and occurred at an input of 12.5% sludge. This concentration is close to the expected theoretical value, however it is not expected to be feasible to recover phosphorus at such a low concentration. The ashes were sent to Fortum Waste Solutions and Ragn-Sells for recovery of phosphorus, however the results are not included in this report due to time constraints for thesis study. In order to increase the concentration of phosphorus in the ashes, a system approach is recommended, for instance, recirculation of bottom ash into the incinerator.Den primära källan till fosfor, fosforit, är en icke-förnybar resurs som är begränsad och förväntas bli förbrukad under de kommande 50-100 åren. Avloppsslam i Sverige innehåller 25% av det årliga fosforflödet, därmed är det en potentiellt viktig källa för fosforåtervinning. Syftet med detta projekt var att identifiera potentialen för fosforåtervinning från förbränning av rötat och avvattnat avloppsslam i Fortum Värmes kraftvärmeverk i Stockholm. Projektet avgränsades till fokus på två pannor i Bristaverket: panna B1, en bioeldad fluidiserad bäddpanna och panna B2, en avfallseldad rosterpanna. En teoretisk analys av panna B1 visade att det är möjligt att uppnå en koncentration på 4,6% fosfor i flygaska om slam och RT-flis blandas med förhållandet 48:52. Ett test program genomfördes på panna B2 för att förbränna uppe till 12,5% slam med en blandning av hushållsavfall och grovkross. Totalt användes 755 ton slam under en period av tre veckor då testet genomfördes i panna B2. Det var ett lyckat test med avseende på förbränning och utsläpp. Ingen ökning av kväveoxider, svaveldioxid och saltsyra i rökgasen observerades vid utsläppen. Kvicksilverutsläppet i skorstenen ökade med en ökad andel slam, dock var utsläppsnivån under den gränsen som är fastställd av Naturvårdsverket. Minskning av oförbrända material i bottenaska och i utsläpp av kolmonoxid visade att förbränningen av bränsle är effektivare med inmatning av slam. Den maximala fosforkoncentrationen var 0,7% i både bottenaska och flygaska från panna B2 vid ett intag av 12,5% slam. Denna koncentration ligger nära det förväntade teoretiska värdet, men det anses inte vara rimligt att återvinna fosfor vid en sådan låg koncentration ut ett ekonomist perspektiv. Askan skickades till Fortum Waste Solutions och Ragn-Sells för återvinning av fosfor, men resultatet redovisas inte i denna rapport på grund av tidsbegränsningen av detta examensarbete. För att öka koncentrationen av fosfor i askan rekommenderas en systeminriktning, till exempel recirkulation av bottenaska i pannan.
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Mann, Cindy Mary, of Western Sydney Hawkesbury University, and Faculty of Science and Technology. "Salmonella regrowth potential of two sewage sludge products." THESIS_FST_XXX_Mann_C.xml, 1997. http://handle.uws.edu.au:8081/1959.7/361.
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The disposal of sewage sludge is becoming an ever-increasing problem and a range of re-use options are being developed, with traditional composting and advanced alkaline stabilisation emerging as priority re-use alternatives in NSW. However, concerns have been raised regarding the dissemination of sludge related pathogens in the environment. Salmonella spp pose the greatest risk since they have the ability to proliferate in the absence of human and animal hosts. Composting processes eliminate salmonellae from sludge, but the opportunity for post-processing recontamination is considerable. This project examined the significance of post-processing recontamination of Salmonella broughton, introduced into composted sludge and N-Virosoil. In compost, inactivation rates of S. broughton showed an inverse relationship with simulated processing temperatures, with competitive exclusion by autocthonous compost flora thought to be the major mechanism of inhibition. S. broughton numbers were reduced to below the limits of detection after several weeks. S. broughton inactivation was also assessed in processed N-Virosoil and was found to be more immediate. It was concluded that both compost and N.Virosoil products have a low potential to support the regrowth of Salmonella spp.Master of Science (Hons)(Environmental Science)
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Stark, Kristina. "Phosphorus release and recovery from treated sewage sludge." Doctoral thesis, Stockholm : KTH Architecture and the Built Environment, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-402.
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Wan, Iat-meng, and 溫日明. "Physical characterization of dewatered sewage sludge for landfilling." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1998. http://hub.hku.hk/bib/B31220034.
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Ng, Yue-hang, and 伍宇鏗. "Dewatering and treatment of sewage sludge before landfill." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1995. http://hub.hku.hk/bib/B31253222.
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Martin, Garcia Ignacio. "Sludge free and energy neutral treatment of sewage." Thesis, Cranfield University, 2010. http://dspace.lib.cranfield.ac.uk/handle/1826/6530.
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Anaerobic biological processes have been recognized as the most suitable pathway towards sustainable wastewater treatment due to the lower energy required and the lower amounts of biosolids generated when compared to conventional aerobic technologies. The difficulties experienced with the implementation of anaerobic reactors for the treatment of low strength wastewater at low temperatures are related to the deterioration of treatment capacity and effluent quality due to inefficient removal of colloidal matter and biomass washout. Membrane technology can overcome the limitation of anaerobic bioreactors since they retain not only solids but also colloidal and high molecular weight organics. This thesis explores the potential of anaerobic membrane bioreactors as core technology for mainstream wastewater treatment. The impacts of seed sludge, temperatures and bioreactors configuration on treatment efficiency and membrane performance as well as nutrient removal using ion exchange resins are investigated. Cont/d.
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Mountain, Teresa J. "The microbial leaching and composting of sewage sludge." Thesis, University of Southampton, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.242868.
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Siddall, Roy. "Parasites as biological indicators of sewage sludge dispersal." Thesis, University of Aberdeen, 1992. http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU548816.
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This investigation has demonstrated that levels of parasitism may provide a sensitive, biologically-based index of marine environmental pollution. Flatfish were initially selected as indicator hosts in field studies conducted at an 'accumulating' and two 'dispersing' sewage sludge dump sites in Scottish coastal waters, but the results indicated that they were unsuitable for monitoring sewage sludge dispersal. The common whelk, Buccinum undatum , was selected as an alternative host-parasite system in a seasonal study at the Garroch Head sewage sludge dump site in the Firth of Clyde, where marked spatial concentration gradients exist for a variety of trace contaminants in the sediments. Buccinum is first intermediate host to several species of larval digenean parasites. Parasite prevalence in Buccinum declined significantly along the gradient of increasing contamination of the sediments from approx. 15&'37 at 3km north of the dump to approx. 2&'37 on its periphery. At the reference site approx. 20&'37 of Buccinum were parasitised. Site, seasonal, sex and parasite effects on growth and the effects of exposure to sewage sludge on the age-prevalence relationship and host response to infection were examined. The age structures of Buccinum populations were used to compare mortalities due to fishing, parasitic infection and proximity to the dump site. Patterns in parasite prevalence recorded at the dump site were not correlated with any natural environmental or host related factors that were examined. The most commonly recorded parasite of Buccinum was Zoogonoides viviparus . Experimental studies demonstrated that the free-living miracidium and cercaria of Z.viviparus were the life-cycle stages that were most susceptible to sewage sludge. There was no evidence of sewage sludge toxicity to the parasitic stages within intermediate or flatfish definitive hosts. However, the survival of Baccinum was reduced by parasitism and experimental exposure to sewage sludge, and in a combination these two factors acted synergistically. The gradient in parasitism in Buccinum at the Garroch Head dump site is considered to result primarily from the toxic effects of trace metals on the miracidium, reducing parasite transmission to the molluscan host. The Buccinum -parasitesystem may therefore provide a sensitive and valuable index for monitoring the dispersal of these contaminants around the Garroch Head sewage sludge dump site. The potential role for a parasite-based index in marine pollution monitoring studies is discussed in the light of this investigation.
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Mills, Nick. "Unlocking the full energy potential of sewage sludge." Thesis, University of Surrey, 2016. http://epubs.surrey.ac.uk/809984/.
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The UK water industry has huge, but as yet under-developed, potential to generate sustainable energy from the main by-product created in the treatment of wastewater. Sewage sludge is an energy rich sustainable biomass resource with a similar calorific value to woodchip. Until recently, technologies and processes for further energy recovery have not been efficient or viable for large-scale use, but this research has shown that developments and innovations are now available and can realistically be brought into use. Using a combination of detailed techno-economic analysis and data from several large scale demonstration plants this research has shown that the renewable energy produced from sewage sludge in the UK could be significantly increased. A typical conventional AD site will achieve 15% electrical conversion efficiency; this can be improved to 20% with the Thermal Hydrolysis Process (THP). Second generation THP developed during the project could boost recovery to 23% with other benefits such as reduced support fuel requirements and sludge transport volumes. By combining THP, sustainable thermal drying and pyrolysis, gross conversion efficiencies of 34% to electricity are achievable. All of the scenarios developed by the project have been proven to environmentally & economically sustainable and have been demonstrated at a large scale as part of this project. A UK wide study in conjunction the Department of Energy & Climate Change showed that an economic deployment across the UK of second generation THP, followed by drying and pyrolysis, could generate to 2,216GWh or an additional 1,310GWh pa of renewable electricity from sewage sludge.
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Day, A. D., M. A. Solomon, M. J. Ottman, and B. B. Taylor. "High Rates of Sewage Sludge in Barley Production." College of Agriculture, University of Arizona (Tucson, AZ), 1989. http://hdl.handle.net/10150/201052.
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A greenhouse experiment was conducted at the University of Arizona, Tucson, Arizona, to study the effects of liquid sewage sludge loading rates on the vegetative growth, yield, and quality of barley grain and straw. Vegetative growth, grain yields, and straw yields were similar whether barley was grown with inorganic N or equivalent amounts of plant-available N from sewage sludge. Sewage sludge loading rates higher than three times the recommended plant-available N rate decreased barley stands in the seedling stage. The loss of stand was compensated for by higher tillering later in the season. High sludge loading rates tended to delay maturity, increase tillering and increase straw yield; however, they did not affect grain yield. Concentrations of cadmium (Cd), copper, (Cu), lead (Pb), nickel (Ni), and zinc (Zn) in barley grain and straw and the amounts of heavy metals recovered in the soil following each harvest were similar to the control for all sewage sludge treatments.
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Day, A. D., M. A. Solomon, M. J. Ottman, and B. B. Taylor. "High Rates of Sewage Sludge in Wheat Production." College of Agriculture, University of Arizona (Tucson, AZ), 1989. http://hdl.handle.net/10150/201070.
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A greenhouse experiment was conducted at the University of Arizona, Tucson, Arizona, to study the effects of sewage sludge loading rates on the vegetative growth, yield, and heavy metal contents of wheat grain and straw. Vegetative growth, grain and straw yields were similar whether wheat was fertilized with the recommended rate of inorganic N (112 kg/ha) or equivalent amounts of plant-available N from sewage sludge. Sewage sludge loading rates higher than three times the recommended plant- available N level delayed maturity and decreased wheat stands in the seedling stage; however, grain and straw yields were similar for all sewage sludge loading rates. Concentrations of cadmium (Cd), copper (Cu), lead (Pb), nickel (Ni), and zinc (Zn) in wheat grain and straw and in the soil following each harvest were low and similar for all fertilizer treatments.
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Day, Arden, Spencer Swingle, Brooks Taylor, Ian Pepper, and Martha Minnich. "Effects of Sewage Sludge on Wheat Forage Production." College of Agriculture, University of Arizona (Tucson, AZ), 1987. http://hdl.handle.net/10150/203765.
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Experiments were conducted in Avra Valley, Arizona, to study the use of digested liquid sewage sludge as a source of plant nutrients in the commercial production of green-chopped feed and hay from wheat. Wheat grown with the recommended amount of plant-available nitrogen from sewage sludge produced more green-chopped feed and hay than did wheat grown with the same amount of nitrogen from inorganic fertilizer. Wheat green-chopped feed and hay grown with sewage sludge and inorganic fertilizer had similar livestock feeding qualities. Fertilizing wheat with sewage sludge delayed maturity.
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Day, A. D., B. B. Taylor, I. L. Pepper, and M. M. Minnich. "Effects of Sewage Sludge on Cotton Lint Quality." College of Agriculture, University of Arizona (Tucson, AZ), 1988. http://hdl.handle.net/10150/204507.
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Three field experiments were conducted in Avra Valley, Arizona, in 1986, to compare the lint quality of upland cotton fertilized with liquid sewage sludge with the lint quality of cotton fertilized with commercial inorganic fertilizer. Most lint quality components were similar for cotton fertilized with sewage sludge or inorganic nitrogen. Fertilization of cotton with sewage sludge tended to increase lint yield and decrease lint quality. Fertilization of cotton with sewage sludge increased vegetative growth and delayed lint maturity.
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Massanet-Nicolau, Jaime. "Mesophilic fermentative hydrogen production from sewage biosolids." Thesis, University of South Wales, 2009. https://pure.southwales.ac.uk/en/studentthesis/mesophilic-fermentative-hydrogen-production-from-sewage-biosolids(45d910c7-f8d1-4c9d-bc46-ca0b80de8361).html.
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The increasing cost of fossil fuels, combined with concerns about their impact on our environment has led to a renewed interest in hydrogen as a clean, sustainable, alternative energy vector. Using sewage biosolids as the substrate for fermentative hydrogen production offers several advantages over the use of other biomass sources. It is available at little or no cost and is abundant, being produced wherever there are human settlements, with 1.3 million tonnes (dry solids) per year currently being produced in the U.K alone. This research demonstrated the feasibility of hydrogen production from sewage biosolids via anaerobic fermentation. To do this a number of issues specifically relating to the nature of sewage biosolids had to be addressed. Firstly, the solids content and rheology made automatic feeding difficult. The feedstock also contained high levels of indigenous microorganisms and a high ratio of insoluble to soluble carbohydrate. To address these challenges, a novel reactor design using wide bore tubing and computer controlled pumping equipment was successfully used to construct a working continuously fed bio-reactor. A combination of heat treatment at 70°C for one hour and pre-treatment with a commercially available food processing enzyme mixture was found to be the most efficient method of inactivating competing microorganisms and improving substrate quality. Hydrogen was successfully produced via batch fermentation of primary sewage biosolids which had undergone heat treatment and enzymatic digestion. When fermentation took place at pH 5.5 a peak hydrogen production rate of 3.75 cm3 min"1 was observed. At this pH the hydrogen yield was 0.37 mol H2 mol~ : carbohydrate, equivalent to 18.14 L H2 kg"1 dry solids. Fermentative hydrogen production from sewage biosolids was also demonstrated in a five litre, continuously fed bio-reactor for the first time. A comparison of different hydraulic retention times showed that hydrogen production was most stable at a HRT of 24 hours. A hydrogen producing fermenter was successfully linked to a methanogenic bio-reactor in a two stage digestion process.
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Haseltine, Michael H. "The effect of inert biomass support media on activated sludge treatment of a high-strength industrial wastewater." Thesis, This resource online, 1991. http://scholar.lib.vt.edu/theses/available/etd-12052009-020051/.
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Molwantwa, Jennifer Balatedi. "The hydrolysis of primary sewage sludge under biosulphidogenic conditions." Thesis, Rhodes University, 2003. http://hdl.handle.net/10962/d1004020.
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The potential for using readily available and cost-effective complex carbon sources such as primary sewage sludge for a range of environmental remediation processes, including biological sulphate reduction, biological nutrient removal and the bioremediation of acid mine drainage, has been constrained by the slow rate of solubilization and low yield of soluble products, which drive the above mentioned processes. Previous work conducted by the Environmental Biotechnology Group at Rhodes University indicated that the degradation of primary sewage sludge was enhanced under sulphate reducing conditions. This was proven in both laboratory and pilot-scale (Reciprocating Sludge Bed Reactor) systems, where the particulate matter accumulated in the sludge bed and the molecules in smaller flocs were rapidly solubilized. The current study was aimed at investigating in more detail the factors that govern the enhanced hydrolysis under sulphate reducing conditions, and to develop a descriptive model to explain the underlying mechanism involved. The solubilization of primary sewage sludge under sulphate reducing conditions was conducted in controlled flask studies and previously reported findings of enhanced hydrolysis were confirmed. The maximum percentage solubilization obtained in this study was 31% and 63% for the methanogenic and sulphidogenic systems respectively, and this was achieved over a period of 10 days. A rate of reducing sugar production and complex molecule breakdown of 51 mg. L⁻¹.hr⁻¹ and 167 mg.L⁻¹.hr⁻¹ was observed for the methanogenic and sulphidogenic systems respectively. The flask studies revealed that during hydrolysis of primary sewage sludge under sulphidogenic conditions there was enhanced production of soluble products, specifically carbohydrates (reducing sugars) and volatile fatty acids, compared to methanogenic conditions. The rate at which these products were utilized was also found to be more rapid under sulphidogenic as compared to methanogenic conditions. A study of the distribution of volatile fatty acids indicated that acetate was utilized preferentially in the methanogenic system, and that propionate, butyrate and valerate accumulated with time. The converse was found to occur in the sulphidogenic system. The descriptive model developed from the results of this study was based on the fact that a consortium of bacteria, composed of hydrolytic, acidogenic and acetogenic species, carries out the solubilization of complex carbon sources. Furthermore, it is essential that equilibrium between product formation and utilization is maintained, and that accumulation of soluble end products impacts negatively on the rate of the hydrolysis step. It is therefore proposed that the relatively poor utilization of VFA and reducing sugars in the methanogenic system activates a negative feedback inhibition on the hydrolytic and/ or acidogenic step. This inhibition is reduced in the sulphidogenic system where the utilization of end products is higher.
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Tsang, Wai Lik. "Performance of sulfate reduction, autotrophic denitrification, and nitrification integrated process (SANI process) for saline sewage treatment /." View abstract or full-text, 2007. http://library.ust.hk/cgi/db/thesis.pl?CIVL%202007%20TSANG.
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Buckley, Margaret M. "Conditioning for shear in sludge dewatering." Thesis, This resource online, 1994. http://scholar.lib.vt.edu/theses/available/etd-09052009-040620/.
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Yang, Wing-ning. "Management of dewatered sludge in Hong Kong /." View the Table of Contents & Abstract, 2006. http://sunzi.lib.hku.hk/hkuto/record/B37118833.
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O'Palko, Brian A. "The use of a microbubble dispersion to enhance a dissolved air flotation system in a wastewater treatment sludge media." Thesis, This resource online, 1991. http://scholar.lib.vt.edu/theses/available/etd-10222009-125034/.
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Papanicolaou, Athanasios N. "Settling characteristics of particles in a suspension of medium to high solids concentration." Thesis, This resource online, 1992. http://scholar.lib.vt.edu/theses/available/etd-05042010-020238/.
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Wong, Tak Ian. "Numerical flow simulations of an egg-shaped anaerobic sludge digester in wastewater treatment /." View abstract or full-text, 2005. http://library.ust.hk/cgi/db/thesis.pl?EVNG%202005%20WONG.
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Qi, Yinan. "Effect of centrifugal dewatering on the regrowth of fecal coliforms and Salmonella in anaerobically digested biosolids." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 192 p, 2008. http://proquest.umi.com/pqdweb?did=1601522491&sid=2&Fmt=2&clientId=8331&RQT=309&VName=PQD.
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Thesis (Ph.D.)--University of Delaware, 2008.Principal faculty advisors: Steven K. Dentel, Dept. of Civil & Environmental Engineering; and Diane S. Herson, Dept. of Biological Sciences. Includes bibliographical references.
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Copp, John B. "COD balances in biological nutrient (nitrogen and phosphorus) removal activated sludge systems /." *McMaster only, 1998.
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Rodríguez, Rodríguez Carlos E. "Degradation of pharmaceuticals in sewage sludge by Trametes versicolor." Doctoral thesis, Universitat Autònoma de Barcelona, 2012. http://hdl.handle.net/10803/117673.
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Dada la ineficiencia de las plantas de tratamiento de aguas residuales para eliminar completamente los contaminantes orgánicos, los lodos en ellas producidos constituyen una importante fuente de agentes tóxicos. Consecuentemente, la cada vez más popular práctica de aplicar lodos in tierras de uso agrícola resulta en la diseminación de estos microcontaminantes en el ambiente. El presente trabajo describe el desarrollo de una estrategia biotecnológica para la eliminación de contaminantes emergentes en lodos de depuradora, con particular énfasis en compuestos farmacéuticos, y basado en la aplicación de un hongo de la podredumbre blanca (white-rot fungus), Trametes versicolor. Este hongo es conocido por su amplia capacidad degradativa de organocontaminantes.
La primera etapa de la investigación describe la evaluación preliminar de la colonización de sistemas de lodos estériles por parte del hongo (fase sólida y suspensión o “slurry”) y la capacidad de degradación de dos drogas terapéuticas modelo (carbamazepina y naproxeno) en dichos sistemas. El desarrollo de una prueba de degradación llamada ND24, diseñada para el monitoreo del estatus metabólico de T. versicolor en procesos de biorremediación en fase sólida es también descrita.
A continuación, en una segunda etapa, los tratamientos en fase sólida y bioslurry fueron empleados para la degradación de fármacos, a concentraciones preexistentes, en lodos de depuradora estériles. Esta parte del trabajo fue llevada a cabo en condiciones estériles para demostrar que la eliminación se debe al hongo y no a las comunidades microbianas presentes en los lodos. En los sistemas de fase sólida (biopilas), una eliminación importante fue observada para todos los agentes terapéuticos detectados, así como una destacable reducción en la toxicidad. Similarmente, la eliminación de fármacos y otros grupos de contaminantes emergentes fue también conseguida en los reactores en “slurry”. Sin embargo, en términos de toxicidad y eliminación, el tratamiento en fase sólida mostró un mejor rendimiento comparado con el bioslurry, razón por la cual, las biopilas fueron posteriormente empleadas para el tratamiento de lodo no estéril.
La tercera etapa consistió en la aplicación de T. versicolor en biopilas no estériles para la eliminación de fármacos preexistentes en lodos. Este proceso de bioaumentación fue comparado con la acción de únicamente los microorganismos autóctonos. Mediante técnicas moleculares se pudo dar monitoreo a la colonización y supervivencia de T. versicolor en el proceso y su efecto sobre las comunidades microbianas, paralelo a la degradación de los agentes terapéuticos.
En un intento por obtener mayores detalles en el mecanismo de degradación, la transformación de varias sulfonamidas, usualmente encontradas en los lodos y eliminadas por el hongo, fue estudiada en profundidad. Los resultados incluyen la identificación de productos de transformación y la participación de algunas enzimas. El uso de un reactor de lecho fluidizado con pellets de T. versicolor para la eliminación simultánea de tres sulfonamidas es también descrito.Given the the inefficiency of sewage treatment facilities to completely remove organic pollutants, the sludge produced in wastewater treatment plants constitutes an important source of contaminants. Subsequently, the increasingly popular practice of applying sludge in agricultural lands results in the spread of these micropollutants in the environment. The present work describes the development of a biotechnological approach based on the application of a white-rot fungus, Trametes versicolor, for the elimination of emerging contaminants, in particular pharmaceuticals, from sewage sludge. This fungus is known for its wide spectrum of degradation ability towards organopollutants. The first stage in the research deals with the preliminary assessment of fungal colonization of sterile sludge systems (solid-phase and slurry) and the capacity of degradation of two model pharmaceuticals (carbamazepine and naproxen) in those systems. The development of a degradation test called ND24, designed to monitor the metabolic status of T. versicolor in solid-phase bioremediation process is also described. Afterwards, in a second stage, the solid-phase and the biosurry treatments were employed for the degradation of pharmaceuticals at pre-existent concentrations from sterile sewage sludge. Work was undergone in sterile conditions in order to demonstrate that removal was due to the fungus and not to the microbial communities present in the sludge. In the solid-phase biopiles an important removal was observed for all the drugs detected, together with a remarkable reduction in the global toxicity. Similarly, elimination of pharmaceuticals and other groups of emerging pollutants was achieved in the slurry bioreactor. However, in terms of toxicological and removal values, the solid-phase biopiles showed an enhanced performance compared to the slurry, reason why the current were further employed for the treatment of non-sterile sludge. The third stage consisted in the application of T. versicolor in non-sterile biopiles for the elimination of pre-existent pharmaceuticals from sludge. This bioaugmentation process was compared with the action of solely the autochthonous microbiota. Molecular techniques permitted to monitor the colonization and survival of T. versicolor in the process and its effect over the microbial communities, parallel to the removal of the therapeutic drugs. In an attempt to obtain further insights in the mechanism of degradation, the transformation of several sulfonamides, usually found in the sludge and removed by the fungus, was studied in detail. Results include the identification of transformation products and the participation of some enzymes. The use of a continuous fluidized bed reactor with fungal pellets for the simultaneous removal of three sulfonamides is also described.
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Rodriguez, Chiang Lourdes Maria. "Methane potential of sewage sludge to increase biogas production." Thesis, KTH, VA-teknik, Vatten, Avlopp och Avfall, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-96294.
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Sewage sludge is treated with the biological process of anaerobic digestion in which organic material of a substrate is degraded by microorganisms in the absence of oxygen. The result of this degradation is biogas, a mixture mainly of methane and carbon dioxide. Biochemical Methane Potential tests are used to provide a measure of the anaerobic degradability of a given substrate. This study aims to determine the methane potential in Sjöstadsverket’s sludge this will moreover determine the viability of recycling the digested sludge back into the anaerobic system for further digestion. Batch digestion tests were performed in both Sjöstadsverket’s (S1) and Henriksdal’s (H2) sludge, for a reliable comparison. An inoculum to substrate ratio of 2:1 based on VS content was used and BMP tests presented results that S1 and H2 in the 20 days of incubation produced 0.29 NLCH4/gVS and 0.33 NLCH4/gVS respectively. A second experiment considering the same amount of substrate (200ml) and inoculum (200ml) for each sample, showed that Control S1 had a higher methane potential than Control H2, 0.31 NL/gVS and 0.29 NL/gVS respectively. All the samples containing Sjöstadsverket’s inoculum presented a higher volume of total accumulated gas (measured in Normal Liters), however methane potentials are low. Results demonstrated that methane production in samples S1 and Control S1 was originating from the grams of VS in the inoculum itself after depletion of all the soluble organic material in the substrate. This suggested that Sjöstadsverket’s sludge can endure a higher organic load rate and that the digested sludge still has potential to produce biogas, hence the recycling of this can enhance the biogas production in the digestion system.
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Ang, May Lin. "Development of a novel bioreactor to reduce sewage sludge." Thesis, University of Hull, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.431061.
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Das, Mohar. "Anaerobic codigestion of food waste with raw sewage sludge." Thesis, University of Manchester, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.498950.
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