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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Avaliação das caraterísticas físico-químicas e microbiológicas da produção de hidrogênio e homoacetogênese a partir de resíduos do processamento de café / Evaluation of phyical-chemical and microbiological characteristics in hydrogen production and homoacetogenesis from coffee processing wastes

Montoya, Alejandra Carolina Villa 17 May 2019 (has links)
O processamento do café via úmida inclui as etapas de despolpamento, fermentação, lavagem e separação dos grãos, no qual gera-se grande quantidade de resíduos sólidos (casca e polpa) e água residuária. O estudo dos aspectos microbiológicos na produção de hidrogênio a partir de resíduos do processamento do café é pouco explorado, o que torna esse resíduo atrativo e foco de pesquisas. Neste cenário, buscou-se avaliar o potencial uso destes resíduos como substrato e fonte de bactérias e fungos fermentativos para produção de H2. Adicionalmente, estudou-se a homoacetogênese, processo que afeta a produção de H2, uma vez que o H2/CO2 pode ser consumido para a síntese de ácido acético. Para isso, ensaios em reatores em batelada foram conduzidos para seleção da melhor condição de pré-tratamento hidrotérmico (severidade), dos fatores da fermentação (pH, temperatura, agitação, volume do headspace, concentração de bioaumentação do consórcio microbiano, resíduo de polpa e casca, água residuária e extrato de levedura) que afetam a produção de H2 (Planejamento Plackett-Burman) e homoacetogênese (planejamento fracionado 24-1), seguido do delineamento composto central rotacional (DCCR) para otimização da produção de hidrogênio. Verificou-se que a severidade de pré-tratamento hidrotérmico de 3,53 (180 °C, 15 minutos), resultaram no aumento da concentração de açúcares fermentáveis, com baixa concentração de lignina, fenol, furfural e 5-hidroximentil furfural, obtendo valores de potencial máximo de produção de H2 (P) de 1,8 mL H2. Em relação ao efeito dos fatores da fermentação sobre a produção de H2, obteve-se o maior P de 82 mL H2 em pH 7,0, 30 g DQO L-1 de água residuária, 6 g L-1 de polpa e casca, 30 ºC, 50% de headspace, 180 rpm, sem bioaumentação do consórcio microbiano e 2 g L-1 de extrato de levedura. Por outro lado, as condições que conduziram a consumo significativo de H2 por homoacetogênese foram em pH inicial entre 5,5 e 7,5, headspace entre 40 e 60%, concentração de água residuária entre 10 e 30 g DQO L-1 e concentração de casca e polpa entre 3 e 9 g L-1. Em relação às variáveis estatisticamente significativas (pH, concentração de polpa e casca e volume do headspace), as condições operacionais ótimas para obtenção de P de 240 mL H2, estimadas via planejamento DCCR, foram em pH 7,0, concentração de polpa e casca 7 g L-1 e volume de headspace 30%. No consórcio microbiano, houve predominância de bactérias semelhantes a Lactobacillus sp. e Clostridium sp. e de fungos semelhantes a Saccharomyces sp. e Kazachstania sp. Tais microrganismos foram associados a produção de ácido lático, H2, etanol e ácido acético nos reatores, identificando genes relacionados a enzimas para a degradação de lignina, fenol, celulose, hemicelulose e pectina. Observou-se alta abundância relativa de Clostridium sp. tanto nos ensaios de produção de H2 quanto nos ensaios com consumo de hidrogênio, sendo seus genes associados a homoacetogênese, produção de ácido propiônico e butanol. / Wet coffee processing includes pulping, fermentation, washing and grain separation, in which large amounts of solid waste (husk and pulp) and wastewater are generated. The study of microbiological aspects in the hydrogen production from coffee waste was little explored, which makes this residue attractive and the focus of research. In this scenario, we evaluate the potential use of coffee waste as substrate and source of fermentative bacteria and fungi for H2 production. In addition, homoacetogenesis, a process, that negatively affects H2 production, was studied since H2/CO2 can be consumed for acetic acid production. Assays in batch reactors were conducted to select the best hydrothermal pretreatment condition (severity), fermentation factors affecting the H2 production (pH, temperature, agitation, headspace, bioaugmentation of microbial consortium, concentration of pulp and husk, wastewater and yeast extract) (Plackett and Burman design) and homoacetogenesis (fractional factorial design 24-1), followed by the Rotational Central Composite Design (RCCD) to optimize the H2 production. It was verified that the hydrothermal pretreatment severity of 3,53 (180 °C, 15 minutes), resulted in the increase of fermentable sugars, with low concentration of lignin, phenol, furfural and 5-hydroxyximethyl furfural, obtaining values of the maximum H2 production potential (P) of 1,8 mL H2. The fermentation factors conducing to highest P of 82 mL H2 were pH 7,0, wastewater 30 g COD L-1, 6 g L-1 pulp and husk, 30 °C, 50% headspace, 180 rpm, without bioaugmentation of the microbial consortium and 2 g L-1 yeast extract. On the other hand, the conditions leading to significant H2 consumption by homoacetogenesis were initial pH between 5,5 and 7,5, headspace between 40 and 60%, wastewater concentration between 10 and 30 g COD L-1 and concentration of husk and pulp between 3 and 9 g L-1. In relation to the fermentation factors statistically significant in the H2 production (pH, pulp and husk concentration and headspace), the optimal operational conditions to obtain P of 240 mL H2, estimated through RCCD design, were at pH 7,0, 7 g L-1 pulp and husk concentration and 30% headspace volume. In the microbial consortium, there was a predominance of bacteria similar to Lactobacillus sp. and Clostridium sp. and fungi similar to Saccharomyces sp. and Kazachstania sp. These microorganisms were associated with the production of H2, lactic acid, ethanol and acetic acid in the reactors, identifying genes related to enzymes for the degradation of lignin, phenol, cellulose, hemicellulose and pectin. There was a high relative abundance of Clostridium sp. both in the H2 production assays and in the H2 consumption assays, with genes associated to homoacetogenesis, production of propionic acid and butanol.
42

Migration of E. coli and solutes to tile drains via preferential and matrix flow

Moreno, Daniel 21 March 2002 (has links)
The extent of agricultural drainage has created concern for its potential undesirable effects on surface water quality. Land applications of liquid manure on tile drain fields have the potential to transport solutes and bacteria to the drains following precipitation or irrigation events and many times are directly sent to a surface water body, and have been documented as a source of contamination of surface waters. This study determined the potential for and magnitude of E. coli and solute migration to tile drains through the soil profile. Water from subsurface drains was analyzed for chemical and bacterial composition following tracer applications. Two sites were selected for the study to determine transport at large (field) and small (plot) scales. At the large-scale site, both tracers, bacteria (E. coli and Total Coliform) and Amino-G (a conservative tracer), were used to monitor the speed of transport from the surface to the tile drain following liquid manure applications, tracer applications and additionally precipitation events. The concentrations of E. coli were monitored every hour for 76 days during the spring. Both tracers, bacteria and Amino-G, were detected in the tile drainage shortly after precipitation events. The peak concentration of E. coli was observed to be 1.2 x 10⁶ CFU/l00mL. These elevated concentrations of E. coli might be attributed to the characteristics of the soil, high organic matter and well-structured clay soils. Both the rapid breakthrough of tracer to the tile drain and the peaks of tile water temperature during precipitation events provided evidence of macropore flow. Antecedent soil moisture and warmer temperatures appeared to provide ideal conditions for bacteria growth. The small-scale study site was selected for a more focused study. The purpose of this site was to quantify more accurately the percent mass of surface applied tracer that was transported to the tile drain, allowing mass balance calculations. Experiments were conducted during the summer to control the rate and total amount of irrigation. Amino-G readings were taken every 10 seconds for 125 hours of continuous irrigation. Tracer applications were conducted at runoff and non-runoff conditions. Both types of tracer applications had Amino-G breakthrough in less than 10 minutes after initiation of irrigation. Tracer applied at runoff rates resulted in 4 to 17 times more total tracer mass migrating to the tile drain than when applied at non-runoff rates. The total mass of Amino-G migrating to the tile drain during non-runoff conditions depended on the total volume of applied tracer, regardless of the tracer concentration. For an application of 5.6 mm at 12 mg/L, 5.7% of the total applied tracer migrated to the tile drain, whereas for an application of 1.9 mm at 27.7 mg/L only 2.8% of the total applied tracer migrated to the tile drain. Tile flow response to irrigation experiments appeared to be governed by soil moisture. Lysimeter samples were taken continuously every 4-8 hours until the 94th hour after tracer application. Tile water concentrations were consistently greater than concentrations found in the deeper suction lysimeters at corresponding times, providing further evidence of preferential flow. E. coli transported through the soil and into the drains were demonstrated to be event-driven by precipitation events and irrigation events. In addition, the characteristics of this type of soil - the high clay content, the well-defined structure, the high level of organic matter and rich biological activity has been known to enhance the preferential pathways and transport processes in the soil profile, resulting in rapid transport of surface applied solutes and effluents to tile drains. / Graduation date: 2003
43

The effects of increased corn-ethanol production on U.S. natural gas prices

Whistance, Jarrett. Thompson, Wyatt. January 2009 (has links)
The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file. Title from PDF of title page (University of Missouri--Columbia, viewed on January 26, 2010). Thesis advisor: Dr. Wyatt Thompson. Includes bibliographical references.
44

Converting coconut husks into binderless particle board

Greer, Stanton. Bradley, Walter Lee, January 2008 (has links)
Thesis (M.S.M.E.)--Baylor University, 2008. / Includes bibliographical references (p. 54).
45

The kinetics of non-catalyzed supercritical water reforming of ethanol

Wenzel, Jonathan E., Lee, Sunggyu. January 2008 (has links)
Title from PDF of title page (University of Missouri--Columbia, viewed on March 2, 2010). The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file. Dr. Sunggyu Lee, Dissertation Advisor. Vita. Includes bibliographical references.
46

Avaliação do potencial de produção de biogás dos resíduos da suinocultura codigeridos com resíduos agrícultura brasileira / Evaluation of the potential of the biogas production of swine residues codigerated with brazilian agricultural waste

Caillot, Vanessa Alueth 27 April 2017 (has links)
Capes; CNPq / A suinocultura resulta em uma série de resíduos que se não tratados de forma adequada poluem o meio ambiente. A Produção de biogás a partir destes resíduos através da digestão anaeróbica (DA) transforma um passivo ambiental em matéria prima para a produção de energia. No entanto a DA está longe de ser um processo simples, fatores como composição do resíduo, toxicidade, operação da produção podem limitar a produção de biogás. A codigestão anaeróbica, a digestão simultânea de dois ou mais substratos, é uma opção viável para superar as desvantagens da monodigestão, melhorando a produção de biogás. O Brasil possui grande potencial agrícola, atividade que também gera uma quantidade significativa de resíduos, desta forma o objetivo desta pesquisa consistiu em avaliar o potencial de ampliação da produção de biogás dos resíduos da suinocultura codigeridos com os principais resíduos agrícolas produzidos no Brasil. Os resultados foram alcançados através de um portfólio Bibliográfico levantado sobre do processo de produção de biogás, seguidos da identificação dos principais resíduos agrícolas produzidos no Brasil, a partir destes resultados iniciou-se pesquisa por palavras chaves nas principais bases de dados internacionais a fim verificar quais resíduos agrícolas produzidos no Brasil podem ser codigeridos com resíduos da suinocultura. Por fim analisou-se a proporção de resíduos utilizada, a quantidade de biogás produzida e as condições de operação do processo. Os resultados indicam que os resíduos de arroz e de milho podem ser codigeridos com os resíduos da suinocultura, as condições operacionais em que houve maior produção de biogás a partir da DA destes resíduos foram identificadas. Desta forma, a produção de biogás pode ser ampliada através da codigestão anaeróbica de resíduos da suinocultura com os resíduos agrícolas de arroz e de milho. / Swine breeding results in a series of wastes that if not properly treated pollute the environment. The biogas production from these residues through anaerobic digestion (AD) transforms an environmental liability into raw material for the production of energy. However the AD is far from a simple process, factors such as composition of the waste, toxicity, production operation can limit the production of biogas. Anaerobic co-digestion, the simultaneous digestion of two or more substrates, is a viable option to overcome the disadvantages of digestion, improving biogas production. Brazil has great agricultural potential, an activity that also generates a significant amount of waste. In this way, the objective of this research was to evaluate the potential for the expansion of biogas production of the swine residues co-digestion with the main agricultural residues produced in Brazil. The results were achieved through a Bibliographic portfolio collected on the biogas production process, followed by the identification of the main agricultural residues produced in Brazil, from these results a search was started for key words in the main international databases in order to verify which agricultural residues produced in Brazil may be co-digestion with swine residues. Finally, the proportion of waste used, the amount of biogas produced and the process operating conditions were analyzed. The results indicate that rice and maize residues can be co-digestion with swine residues; the operational conditions in which there was more biogas production from AD of these residues were identified. In this way, the biogas production can be increased through the anaerobic codigestion of swine residues with agricultural residues of rice and maize.
47

Avaliacao do impacto da atividade agropecuaria na qualidade da agua em areas de captacao superficial nas bacias hidrograficas dos rios Mogi - Guacu e Pardo, Sao Paulo

KATSUOKA, LIDIA 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:44:40Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:57:38Z (GMT). No. of bitstreams: 1 07151.pdf: 11938144 bytes, checksum: de903224eb01dd0d5107eead6b34468a (MD5) / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
48

Efeito das condições de processamento nas propriedades de briquetes produzidos com bagaço e resíduo de limpeza a seco da cana-de-açúcar

Camargo, Julia Maria de Oliveira January 2015 (has links)
Orientadora: Profa. Dra. Juliana Tófano de Campos Leite Toneli / Dissertação (mestrado) - Universidade Federal do ABC. Programa de Pós-Graduação em Energia, 2015. / O uso da biomassa em processos de conversão energética é hoje uma das principais alternativas à utilização dos combustíveis fósseis. Nesse contexto, o aproveitamento energético de resíduos é uma possibilidade de uso da biomassa como fonte de energia sem competir com a área plantada para o cultivo de alimentos. Dentre as principais limitações do uso da biomassa para fins energéticos, podem ser destacadas algumas características como a baixa densidade, a produção dispersa, o estado físico sólido e o teor de umidade, que dificultam o seu manuseio, armazenamento, transporte e aplicação nos processos de conversão energética, devido às limitações dos equipamentos. Uma solução para esses problemas é a densificação da biomassa, por meio da produção de briquetes, por exemplo. Neste sentido, o presente trabalho objetivou avaliar o efeito do teor de umidade e das condições de processamento nas propriedades de briquetes produzidos com bagaço de cana de açúcar, com a biomassa residual coletada após o processo de limpeza a seco de cana picada mecanicamente (RLC) e de blendas de bagaço com RLC, visando o seu aproveitamento energético em processos industriais de cogeração. Primeiramente, realizou-se a caracterização física, química e térmica do bagaço e do RLCin natura através das análises de granulometria, massa específica, poder calorífico inferior e superior, análise imediata e elementar e da composição das cinzas. Posteriormente, foram produzidos briquetes com RLC, bagaço e blendas a partir do material moído (peneira 2mm), de acordo com um planejamento experimental 2³ com 3 pontos centrais em que as variáveis independentes foram: teor de umidade da biomassa, temperatura de compactação e composição das blendas (%bagaço b.s.) sobre a resistência mecânica e densidade energética dos briquetes. Os resultados foram analisados através da metodologia de superfície de respostas e observou-se que há uma tendência ao aumento da densidade energética com o aumento da temperatura e redução do teor de umidade. Para briquetes produzidos com RLC, o aumento da temperatura implicou no aumento da resistência mecânica e na diminuição da expansão volumétrica. Já para briquetes produzidos com bagaço, ocorreu aumento da resistência mecânica e diminuição da expansão volumétrica com o aumento do teor de umidade da biomassa, dentro da faixa analisada. A caracterização físico-química e térmica do RLC e do bagaço confirmaram as características combustíveis desses materiais. / The use of biomass energy conversion processes is, nowadays, one of the main alternatives to fossil fuels. In this context, the energy recovery from waste materials is a possible use for biomass as an energy source, which does not compete with food crops for planted area. Amongst the main limitations for using biomass for energy purposes, some relevant characteristics should be mentioned: low density, dispersed generation, moisture presence and the fact that it is a solid, making its handling, storage, transport and application in energy conversion processes much harder, due to equipment limitations. A solution to these problems is the biomass densification, through the production of pellets or briquettes. The present work aimed at to assess the effect of biomass moisture content and pre-processing conditions on properties of briquettes produced by sugarcane bagasse, DCR and blends of bagasse with DCR, aiming their energetic use in cogeneration industrial processes.Firstly, the in natura samples were undergone analysis to determine their physical, chemical and thermochemical properties, such as particle size, bulk density, ultimate composition, moisture content, volatile matter, fixed carbon ash content, metals content in ash, higher and lower heating value. Secondly, briquettes were produced with sugarcane bagasse, DCR and blends of these materials, according a 2³ factorial experimental design with 3 central points. The independent variables assessed were biomass moisture content, compaction temperature and blend composition (%bagasse d.b.) on mechanical strength and energy density of briquettes.The results had been evaluated through the response surface method and it was observed that there is certain tendency to increase the energy density with increasing temperature and reduced moisture content. For briquettes produced from RLC, the increasing compaction temperature implies the increasing of mechanical strength and on lower volume expansion. On the other hand, for briquettes produced from bagasse, the increasing of mechanical strength and a lower volumetric expansion are obtained through higher biomass moisture content within the analyzed range. The physicochemical and thermal characterization of RLC and bagasse settles the fuel characteristics of these materials.
49

Fermentação semissólida de okara com Saccharomyces cerevisiae r. f. bayanus visando a biotransformação de isoflavonas e melhoria da qualidade nutricional

Giongo, Camila Nascimento 14 November 2013 (has links)
CAPES / O okara é uma biomassa gerada no processamento do extrato hidrossolúvel de soja e do tofu. Tal biomassa tem elevada qualidade nutricional em função do conteúdo de proteínas, fibras e compostos bioativos como as isoflavonas. É gerado em grandes quantidades pela indústria processadora de soja como um subproduto e embora se trate de um material de baixo valor comercial possui em sua composição moléculas com potencial nutricional e funcional. As isoflavonas estão presentes na soja principalmente nas formas conjugadas (β-glicosídicas, acetil e malonil) e, em menor proporção, nas formas livres (agliconas). Diversos estudos comprovam a eficiência das isoflavonas agliconas na prevenção de doenças crônicas. Algumas tecnologias têm sido empregadas para a bioconversão das isoflavonas β-glicosídicas em agliconas baseadas na ação de enzimas β-glicosidases sintetizadas por micro-organismos. Neste contexto, o presente trabalho objetivou a bioconversão de isoflavonas presentes no okara através de fermentação semissólida por Saccharomyces cerevisiae r. f. bayanus, buscando melhorar a qualidade nutricional e propriedades biológicas do okara para uso como ingrediente em produtos alimentícios. A fermentação semissólida foi conduzida a 28 °C durante 72 horas. O processo contribuiu para o aumento dos teores de proteínas e redução do conteúdo de fibra bruta o que pode contribuir para melhorar a digestibilidade do produto. A fermentação proporcionou a biotransformação de isoflavonas conjugadas em agliconas, o que levou ao aumento da quantidade de compostos fenólicos, capacidade antioxidante da biomassa e consequente melhoria da qualidade nutricional. A biotransformação das isoflavonas do okara por processo fermentativo mostrou ser uma estratégia promissora para agregação de valor e melhor aproveitamento da biomassa. / Okara is a biomass generated by the soybean and tofu water soluble extract process. Such biomass has a very important nutritional quality because of the protein content, fibres and bioactive compounds as the isoflavons. It is produced in great amounts by the soybean processing industry as a by-product, although it is a product of low commercial value, it possess on its composition molecules with nutritional and functional potential. The isoflavons are present in the soybean mainly in the combined forms (B-glycosidics, acetyl and molonic) and, in a minor proportion, in the free forms (aglycons). Several studies prove the efficiency of aglycons isoflavons preventing cronicle diseases. Some technologies have been employed for the bioconversion of β-glycosidic isoflavon in aglycons based in the action of enzymes β-glycoside hydrolase synthesized by microorganisms. In this context, the current work has aimed the bioconversion by Saccharomyces cerevisiae r. f. bayanus, trying to improve the okara nutritional quality and biological properties in order to use it as an ingredient in food. The semisolid fermentation has been lead under 28° C per 72 hours. The process was conduction at increase protein and reduction of crude fiber content improving the product digestibility. The fermentation provided a biotransformation of isoflavonscombining aglycons, what has taken to the raise of amount of phenolic compounds, biomasa antioxidant capacity and consequently improving of nutritional quality. The biotransformation of okara isoflavons by fermentation process has should to be a promising strategy for adding value and better use of biomass.
50

Performance evaluation of an up- and down-flow anaerobic reactor for the treatment of poultry slaughterhouse wastewater in South Africa

Basitere, Moses January 2017 (has links)
Thesis (DTech (Chemical Engineering))--Cape Peninsula University of Technology, 2017. / The process of anaerobic digestion (AD) is one of the most cost-effective and environmentally sustainable technologies to treat wastewater in the agricultural sector. In South Africa, in some industries in the agricultural sector, such as the poultry industry in particular, slaughterhouses have the highest consumption of potable water, culminating in the production of a large quantity of high strength wastewater. This high consumption of potable water has become a concern in South Africa due to water scarcity and reduced rainfall attributed to global warming, including weather changes. Furthermore, the generation of a large volume of wastewater poses environmental pollution concerns. The wastewater from poultry slaughterhouses can be quite easily treated to a suitable quality for reuse, using various bioreactor systems that utilise low cost anaerobic digestion processes. However, as this wastewater contains a high quantity of biodegradable organic matter – with the primary pollutants being proteins, blood, fats, oil and grease (FOG) – selecting a suitable anaerobic reactor configuration (up-flow vs down-flow) plays an important role in achieving high reactor performance. In this study, both the up-flow, (i.e. Expanded Granular Sludge Bed Reactor) and the down-flow (i.e. Static Granular Static Granular Bed Reactor), were studied to quantitatively determine their performance in treating poultry slaughterhouse wastewater. Firstly, the feasibility of treating poultry slaughterhouse wastewater with an up-flow Expanded Granular Sludge Bed Reactor (EGSB) coupled with anoxic and aerobic bioreactors was investigated at an HRT of 7 (168 hr), 4 (96 hr) and 3 (72 hr) days using organic loading rates of 0.5, 0.7 and 1.0 gCOD/L.day. The averaged tCOD removal for the EGSB reactor was 40%, 57% and 55%, respectively, at the various OLRs and HRTs investigated. The overall tCOD removal of the system (EGSB-anoxic/aerobic) at high OLR of 1.0 gCOD/L.day was increased to 65%. The redundant performance of the up-flow EGSB reactor was attributed to the periodical sludge washout experienced during its operation due to high FOG and TSS concentrations in the influent. Due to the periodic sludge washout, the reactor required continuous re-inoculation resulting in the EGSB being operated for a short period (i.e. 26 days). As a result of such system deficiency, it was recommended that to improve the performance of the up-flow EGSB reactor in treating poultry slaughterhouse wastewater, a pre-treatment system – such as a Dissolved Air Floatation system (DAFs) or a FOG skimmer – is required to reduce the FOG and total suspended solids (TSS) load prior to the wastewater fed to the EGSB. This will minimise system failure and the need for a continuous re-inoculation of the system (see Appendix C for improved operation strategy of the EGSB reactor). Furthermore, a system redesign was recommended, thus the use of the SGBR. Secondly, after the EGSB system evaluation, the performance of a down-flow system (i.e. SGBR) for the new design, the following were deemed appropriate for improved system (SGBR) design: 1) reduced HRT for high wastewater treatment through-put rates; 2) the ability to adequately treat the wastewater with higher organic loading rates; and 3) reduction of the plant footprint by using a membrane filtration system (i.e. a single process unit) to effectively reduce process requirements needed for the anoxic/aerobic bioreactors (i.e. n=2 process unit) used with the EGSB. Similarly, for large-scale operations, it is advisable to have a backwash system to adequately handle declogging processes (i.e. these systems modifications were evaluated in the SGBR). The SGBR, coupled with an ultra-filtration (UF) membrane system, was then investigated for treating the poultry slaughterhouse wastewater at an HRT of 55 hrs and 40 hrs, including average OLRs of 1.01 and 3.14 gCOD/L.day, respectively. The average maximum performance of the SGBR in terms of tCOD, TSS and FOG removal was > 90% at the OLRs and HRTs investigated. The UF membrane system used as a post-treatment system further yielded a system performance improvement for tCOD, TSS and FOG of 64%, 88% and 60%, respectively. The overall performance of the combined system (SGBR and UF membrane system) in terms of tCOD, TSS and FOG removal was 98%, 99.8% and 92.4%, respectively. The highest performance for the down-flow SGBR was attributed to its ability to retain granulated sludge in the reactor while maximizing the digestion of the organic matter fed into the reactor, even at higher OLRs. Furthermore, for effective declogging, the implementation of a periodic backwash system to effectively remove dispersed fine sludge particles in the underdrain and excessive suspended solids entrapment was observed to ease the system operational deficiencies.

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