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Catalytic wet air oxidation of olive mill wastewater

Gomes, Helder; Figueiredo, José; Faria, Joaquim
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
36.84%
The objective of this work was to study the suitability of catalytic wet air oxidation (CWAO) for the treatment of olive mill wastewater (OMW). Experiments were performed in a high pressure reactor at 100 and 200ºC under an oxygen partial pressure of 6.9 bar, using carbon supported platinum (1 wt.% Pt) and iridium (5 wt.% Ir) catalysts prepared by incipient wetness impregnation. At 100ºC, refractory organic compounds persisted even after prolonged reaction time (8 h). At 200ºC, complete total organic carbon and colour removal was obtained with the Pt/C catalyst after 8 h of reaction. A kinetic model was developed taking into account catalytic and non-catalytic reactions, formation of refractory compounds and catalyst deactivation. Very good agreement between the proposed model and CWAO experimental data at 200ºC was found. The results obtained in this work indicate that Pt/C is a promising catalyst for the CWAO of OMW.

Reúso de água na indústria química - estudo de caso de uma unidade produtiva de nitrocelulose.; Wastewater reuse in the chemical industry - study case of a nitrocellulose unit.

Baum, Daniel
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: dissertação de mestrado Formato: application/pdf
Publicado em 07/10/2011 Português
Relevância na Pesquisa
36.93%
O recurso água é de primordial importância para a vida, para a sociedade e para os processos industriais. A redução da disponibilidade de água, devido ao aumento de sua demanda, à poluição das bacias hidrográficas e à escassez de fontes limpas, pressionam os órgãos reguladores a elaborar leis que restrinjam seu consumo, a criar normas que controlem o despejo de efluentes e aplicar tarifas que elevem o custo do uso da água. Portanto, técnicas de conservação e reúso são elementos importantes para as empresas reduzirem seus custos e contribuírem positivamente com o desenvolvimento sustentável. O objetivo deste trabalho é apresentar um estudo de caso real que visa à redução no consumo de água em uma unidade industrial do setor Químico. Serão aqui descritos os processos industriais envolvidos, as necessidades e especificações associadas, as metodologias utilizadas para construção do cenário atual de consumo e para o desenvolvimento das propostas de reúso. O trabalho mostra que existem oportunidades de modificações nos processos de digestão, de destilação, de recuperação de produtos e de drenagens que implicariam uma redução no consumo de água, em economia financeira com uma taxa de retorno atrativa e com retorno do investimento em um curto espaço de tempo.; Water is essential for life...

Desinfecção de águas servidas através de tratamento térmico utilizando coletor solar; Disinfection of wastewater by heat treatment using solar collector

Damasceno, Ana Paula Alves Barreto
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 17/11/2014 Português
Relevância na Pesquisa
36.93%
O objetivo deste trabalho foi desenvolver um sistema de desinfecção de águas oriundas de esgotos domésticos, no qual seja aproveitado o calor gerado pelo sol, mantendo na água suas características químicas úteis às plantas. O experimento foi desenvolvido em duas etapas, a fim de se verificar sua viabilidade. A primeira etapa foi realizada em laboratório, com amostras de água coletadas no Ribeirão Piracicamirim. Utilizando-se um regulador automático de temperatura, foram realizados testes com o objetivo de verificar a redução de coliformes, sob as temperaturas de 45, 50, 55 e 60°C. Para os testes de quantificação e viabilidade dos ovos de helmintos foi feita a coleta de água residuária, proveniente da Estação de Tratamento de Esgoto (ETE) Piracicamirim. Ao ser encontrada a menor temperatura na qual ocorre a maior redução de coliformes, utilizou-se o mesmo regulador automático de temperatura e procederam-se os testes sob as temperaturas 60, 70, 80, 90 e 100°C, durante o período de 1 hora de exposição. A segunda etapa foi realizada em campo. Foi implantado um sistema composto por placa solar para o aquecimento da água e reservatórios, utilizando como principio a diferença de altura de carga entre os reservatórios de entrada e saída para que a água atingisse a temperatura necessária. Nesta etapa...

Improvement of L(+)-lactic acid production from cassava wastewater by Lactobacillus rhamnosus B 103

Coelho, Luciana Fontes; Bolner de Lima, Cristian J.; Bernardo, Marcela Piassi; Michelena Alvarez, Georgina; Contiero, Jonas
Fonte: Wiley-Blackwell Publicador: Wiley-Blackwell
Tipo: Artigo de Revista Científica Formato: 1944-1950
Português
Relevância na Pesquisa
36.93%
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); BACKGROUND: L(+)-Lactic acid is used in the pharmaceutical, textile and food industries as well as in the synthesis of biodegradable plastics. The aim of this study was to investigate the effects of different medium components added in cassava wastewater for the production of L(+)-lactic acid by Lactobacillus rhamnosus B 103.RESULTS: The use of cassava wastewater (50 g L-1 of reducing sugar) with Tween 80 and corn steep liquor, at concentrations (v/v) of 1.27 mL L-1 and 65.4 mL L-1 respectively led to a lactic acid concentration of 41.65 g L-1 after 48 h of fermentation. The maximum lactic acid concentration produced in the reactor after 36 h of fermentation was 39.00 g L-1 using the same medium, but the pH was controlled by addition of 10 mol L-1 NaOH.CONCLUSION: The use of cassava wastewater for cultivation of L. rhamnosus is feasible, with a considerable production of lactic acid. Furthermore, it is an innovative proposal, as no references were found in the scientific literature on the use of this substrate for lactic acid production. (C) 2010 Society of Chemical Industry

Biofotonica aplicada ao monitoramento microbiologico de efluentes sanitarios; Spontaneous light emission applied to microbiological wastewater monitoring

Samuel Ricardo dos Santos
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: dissertação de mestrado Formato: application/pdf
Publicado em 05/02/2010 Português
Relevância na Pesquisa
36.93%
As bactérias do grupo coliformes têm sido amplamente empregadas no monitoramento da qualidade da água, com o uso da Escherichia coli como microrganismo indicador de contaminação fecal. Os métodos atuais de detecção apresentam no mínimo 18 h para obtenção de resultados e em outros processos, que incluem testes bioquímicos, podem chegar até 48 h para análise conclusiva. A importância de uma rápida detecção de coliformes e Escherichia coli aplicada à qualidade e segurança da água torna-se óbvia e necessária. O uso de medidas da luz, presente em seres vivos, surge como metodologia promissora aplicada ao monitoramento microbiológico das águas, podendo gerar resultados em tempo reduzido de análise. No presente trabalho avaliou-se o potencial da técnica biofotônica aplicada ao monitoramento de efluentes sanitários em seu parâmetro microbiológico, através da detecção de emissão ultrafraca de luz em testes envolvendo coliformes. A metodologia baseou-se no acompanhamento dos padrões de emissão de luz em câmara escura com o uso de efluente doméstico, antes e após tratamento, incubados em meio nutritivo. O controle foi efetuado com o uso de cepa de Escherichia coli (ATCC 25922), incubada em meio nutritivo...

Reúso de efluente de esgoto sanitário anaeróbio e nitrificado em irrigação de roseiras; Reuse of anaerobic and nitrified wastewater effluents for irrigation of roses

Giuliano Gabrielli
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: dissertação de mestrado Formato: application/pdf
Publicado em 28/02/2011 Português
Relevância na Pesquisa
36.93%
Efluentes de estações de tratamento de esgotos com nível de tratamento secundário podem ainda conter nutrientes em quantidades prejudicais ao ambiente. O lançamento desses efluentes podem causar eutrofização dos corpos d`água, tornando a água inapropriada para usos previstos, como abastecimento para consumo humano, atividades de lazer, etc. Além do problema da eutrofização, há a dificuldade de se atender a resolução 357 de 2005 do Conselho Nacional do Meio Ambiente - CONAMA 357 -, que estabelece padrões de qualidade dos corpos d`água com relação a concentração de nitrogênio e fósforo. Assim, uma das maneiras de diminuir o afluxo de nutrientes para os corpos d`água seria pelo reúso agrícola, que ainda leva a economia no uso de fertilizantes. Porém o reúso de esgoto tratado em irrigação pode trazer alguns problemas, entre os quais salinização e sodificação do solo e excesso de nitrato na solução do solo. Por isso é necessário que haja monitoramento das características químicas do solo da área irrigada. Portanto, o objetivo deste trabalho foi avaliar a viabilidade de irrigação de rosas por gotejamento com efluente de esgoto anaeróbio e nitrificado, analisando o grau de salinização e de sodificação do solo...

Disposição de lodo adensado de ETA em ETE com tratamento primário quimicamente assistido; Thickened water treatment sludge disposal in a wastewater treatment presenting a chemically enhanced primary treatment

Vanessa Egidio Pereira
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: dissertação de mestrado Formato: application/pdf
Publicado em 23/08/2011 Português
Relevância na Pesquisa
36.93%
Os sistemas de tratamento, para a potabilização da água ou para a redução da quantidade de poluentes presentes no esgoto antes de seu lançamento em corpos hídricos, englobam processos físicos, químicos e biológicos, sendo a geração de resíduos inerente tanto à concepção das estações de tratamento de água (ETA), quanto das estações de tratamento de esgotos (ETE). Os resíduos sólidos gerados em estações de tratamento de água têm características inorgânicas, sendo eles os resíduos retirados da água bruta por meio de processos químicos e físicos e também os produtos utilizados no condicionamento da água e na coagulação para remoção dessas impurezas. Como alguns estudos apontaram para disposições semelhantes para os dois tipos de resíduos, apesar das características diferentes de cada um, a proposta deste trabalho foi a de avaliar a possibilidade de tratamento combinado desses resíduos, aproveitando as diversas vantagens de cada material e verificando os impactos que podem ser gerados no tratamento do efluente. Utilizando essa premissa, foi avaliado o potencial de utilização de um lodo adensado proveniente de uma ETA como auxiliar em uma ETE que apresenta uma etapa utilizando processo físico-químico de tratamento. O estudo e levantamentos apresentados nesse trabalho tiveram por propósito apontar para uma solução técnica viável para a disposição do lodo gerado na estação de tratamento de água (ETA)...

Ensaios ecotoxicológicos em organismos-teste Daphnia similis e Vibrio fischeri na avaliação de efluentes sanitários aplicados na cultura de eucalipto (Eucaliptus urograndis); Assays in ecotoxicological organisms Daphnia similis and Vibrio fischeri in the evaluation of wastewater applied in culture of eucalyptus (Eucalyptus urograndis)

Giovani Archanjo Brota
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: dissertação de mestrado Formato: application/pdf
Publicado em 28/08/2012 Português
Relevância na Pesquisa
36.93%
O tratamento de esgoto doméstico é de fundamental importância para a manutenção da qualidade dos corpos hídricos e da vida aquática assim como para a conservação dos recursos naturais. Neste foco, os sistemas de tratamento como lagoas de estabilização são largamente utilizados no Brasil para tratamento de efluentes sanitários. O uso de efluente sanitário proveniente do pós-tratamento de lagoa de estabilização utilizado na irrigação de culturas agrícolas é recomendado como prática complementar ao tratamento do efluente, fornecendo assim um aporte de nutrientes necessários ao desenvolvimentos de diversas culturas agrícolas. No entanto essa prática deve ser avaliada quanto aos impactos ambientais. Com esse intuito, foi desenvolvida uma pesquisa para avaliar os potenciais efeitos tóxicos proveniente da aplicação de efluente tratado por lagoas facultativas na cultura de Eucalyptus urograndis. O local escolhido para a pesquisa foi uma área cedida pela ETE Prof. Carmelino Correa Junior (Colégio Agrícola), no município de Franca-SP. A área foi dividida em 8 tratamentos e irrigada de acordo com a dose de "água' recomendada para a cultura de eucalipto da seguinte forma: T1 dose de Água, sem adubação química...

Optimization of in situ derivatization SPME by experimental design for GC-MS multi-residue analysis of pharmaceutical drugs in wastewater

GOMES, Paulo Clairmont Feitosa de Lima; BARLETTA, Juliana Yamashita; NAZARIO, Carlos Eduardo Domingues; SANTOS-NETO, Alvaro Jose; WOLFF, Marya Anne Von; CONEGLIAN, Cassiana Maria Reganhan; UMBUZEIRO, Gisela Aragao; LANCAS, Fernando Mauro
Fonte: WILEY-BLACKWELL Publicador: WILEY-BLACKWELL
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
36.93%
This paper presents the development of a procedure, which enables the analysis of nine pharmaceutical drugs in wastewater using gas chromatography-mass spectrometry (GC-MS) associated with solid-phase microextraction (SPME) for the sample preparation. Experimental design was applied to optimize the in situ derivatization and the SPME extraction conditions. Ethyl chloroformate (ECF) was employed as derivatizing agent and polydimethylsiloxane-divinylbenzene (PDMS-DVB) as the SPME fiber coating. A fractional factorial design was used to evaluate the main factors for the in situ derivatization and SPME extraction. Thereafter, a Doehlert matrix design was applied to find out the best experimental conditions. The method presented a linear range from 0.5 to 10 mu g/L, and the intraday and interday precision were lower than 16%. Applicability of the method was verified from real influent and effluent samples of a wastewater treatment plant, as well as from samples of an industry wastewater and a river.; Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES); Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Life cycle assessment of wastewater treatment options for small and decentralized communities

Machado, A. Patrícia; Urbano, Lino; Brito, A. G.; Janknecht, P.; Salas, J. J.; Nogueira, R.
Fonte: IWA Publishing 2007 Publicador: IWA Publishing 2007
Tipo: Artigo de Revista Científica
Publicado em //2007 Português
Relevância na Pesquisa
36.93%
Sustainability has strong implications on the practice of engineering. Life cycle assessment (LCA) is an appropriate methodology for assessing the sustainability of a wastewater treatment plant design. The present study used a LCA approach for comparing alternative wastewater treatment processes for small and decentralised rural communities. The assessment was focused on two energy-saving systems (constructed wetland and slow rate infiltration) and a conventional one (activated sludge process). The low environmental impact of the energy-saving wastewater treatment plants was demonstrated, the most relevant being the global warming indicator. Options for reduction of life cycle impacts were assessed including materials used in construction and operational lifetime of the systems. A 10% extension of operation lifetime of constructed wetland and slow rate infiltration systems led to a 1% decrease in CO2 emissions, in both systems. The decrease in the abiotic depletion was 5 and 7%, respectively. Also, replacing steel with HDPE in the activated sludge tank resulted in a 1% reduction in CO2 emission and 1% in the abiotic depletion indicator. In the case of the Imhoff tank a 1% reduction in CO2 emissions and 5% in the abiotic depletion indicator were observed when concrete was replaced by HDPE.

SBR performance for synthetic and fishery wastewater treatment

Mesquita, D. P.; Ribeiro, R. R.; Teixeira, D.; Ferreira, E. C.; Coelho, M. A. Z.
Tipo: info:eu-repo/semantics/conferenceobject
Publicado em 07/04/2008 Português
Relevância na Pesquisa
36.93%
The evaluation of a SBR performance treating synthetic and fishery wastewater was performed. Without salt addition, COD and ammonia removal rates over than 50% were obtained, indicating the occurrence of the first nitrification step and COD removal. With 0.5% salt, removal rates lower than 60% were attained, for ammonia removal efficiency probably due to ionic strength changes and cellular plasmolysis leading to inactivation of the nitrification organisms. The SBR performance was greater for synthetic wastewater, due to the inherent and controlled characteristics. For both, lower SVI were achieved as a valuable indicator towards the assessment of the aggregated biomass structure.; National Council of Scientific and Technological Development of Brazil (CNPq); BIEURAM III ALFA co-operation project (European Commission).

Performance evaluation of Portuguese constructed wetlands for municipal wastewater treatment

Duarte, António A. L. Sampaio; Seco, Teresa Canais; Peres, José A.; Bentes, Isabel; Pinto, Jorge
Fonte: WSEAS Press Publicador: WSEAS Press
Tipo: info:eu-repo/semantics/bookpart
Publicado em /05/2010 Português
Relevância na Pesquisa
36.93%
Constructed wetlands have been used as a technology appropriate for the treatment of municipal or domestic wastewater in some villages in Portugal. Most of constructed wetlands present a low cost (installation and maintenance), low energy requirements and technical skills of operators, environment friendly landscape, and good efficiency and reduced production of sludge. In a situation where is a need of appropriate wastewater treatment from a large number of rural villages, it is appropriate to evaluate the performance of some constructed wetlands systems operate in Portugal, in order to validate them as a credible alternative to conventional methods of wastewater treatment. This work presents a characterization of twenty constructed wetlands, an analysis of unit costs of treatment and the unit areas, and proceeds to the evaluation of their efficiency on the main wastewaters quality parameters. Moreover, the analysis identifies the major operational problems of these systems, suggesting a few mitigating measures and/or corrective to both the improvement of its operation, and the streamlining of its procedures for an accurate monitoring.

Changes in the bacterial community structure in two-stage constructed wetlands with different plants for industrial wastewater treatment

Calheiros, Cristina S.C.; Duque, Anouk F.; Moura, Alexandra; Henriques, Isabel S.; Correia, António; Rangel, António O.S.S.; Castro, Paula M.L.
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
Publicado em //2009 Português
Relevância na Pesquisa
36.93%
This study focused on the diversity of bacterial communities from two series of two-stage constructed wetlands (CWs) treating tannery wastewater, under different hydraulic conditions. Series were separately planted with Typha latifolia and Phragmites australis in expanded clay aggregates and operated for 31 months. The effect of plant species, hydraulic loading and unit stage on bacterial communities was addressed through bacterial enumeration and denaturating gradient gel electrophoresis (DGGE). Diverse and distinct bacterial communities were found in each system unit, which was related in part to the type of plant and stage position (first or second unit in the series). Numerical analysis of DGGE profiles showed high diversity in each unit with an even distribution of species. No clear relation was established between the sample collection time, hydraulic loading applied and the bacterial diversity. Isolates retrieved from plant roots and substrates of CWs were affiliated with c-Proteobacteria, Firmicutes, a-Proteobacteria, Sphingobacteria, Actinobacteria and Bacteroidetes. Both series were effective in removing organic matter from the inlet wastewater, however, based on batch degradation experiments it seems that biodegradation was limited by the recalcitrant properties of the wastewater

The effects of tannery wastewater on the development of different plant species and chromium accumulation in phragmites australis

Calheiros, Cristina S. C.; Rangel, António O. S. S.; Castro, Paula M. L.
Fonte: Springer Verlag Publicador: Springer Verlag
Tipo: Artigo de Revista Científica
Publicado em //2008 Português
Relevância na Pesquisa
36.93%
Toxicity tests were performed to assess the effect of tannery wastewater with different treatment levels on two wetland plants, Phragmites australis and Typha latifolia, which are frequently used in constructed wetlands (CWs) for water treatment, and thus deepen the knowledge on their capacity to withstand the application of industrial wastewater. Trifolium pratense, a plant generally used as an indicator in toxicity tests, was included as a control. End points measured were germination percentage, shoot length, root elongation, and biomass growth of the plants. When tannery effluent, with a low treatment level, was supplied to the wetland plants germination occurred even at effluent concentrations of 100%, whereas germination of T. pratense was completely inhibited, almost invariably, at effluent concentration of 50%. Higher germination levels were achieved when the plants were exposed to effluent originating from the outlet of constructed wetland pilot units, allowing germination of all tested plants, indicating a significant decrease in its toxicity level. Experiments conducted with the same plants using different growing substrata as the germination matrix, namely expanded clay aggregates (Filtralite® MR3-8 and Filtralite® NR3-8) and two types of sand (fine gravel and standard sand) have shown that higher germination levels were achieved in standard sand and that P. australis was the plant species showing higher germination in all cases...

Aerobic treatment of winery wastewater with the aim of water reuse

Oliveira, M.; Queda, C.; Duarte, E.
Fonte: IWA Publishing Publicador: IWA Publishing
Tipo: Artigo de Revista Científica
Publicado em //2009 Português
Relevância na Pesquisa
36.93%
An air micro-bubble bioreactor (AMBB) using a free self-adapted microbial population, 15dm3 working volume, was used for aerobic treatment of winery wastewater. This reactor utilizes a Venturi injector in conjunction with mass transfer multiplier nozzles, which allow an efficient oxygen transfer. The reactor can operate in batch or continuous conditions. The dynamics of chemical oxygen demand (COD), biomass and total contents of polyphenolic compounds was followed throughout each trial. The wastewater COD ranged between 4.0–8.0 kgCODm23 and the efficiency of the batch treatment was about 90.0 ^ 4.3%, after 6 days of operation. The maximum efficiency obtained was achieved after 15 days of treatment (99%). In continuous conditions, the loading rate and the treatment efficiency ranged between 0.45–1.00 kgCODm23 d21 and 93.3 ^ 2.0%, respectively. The AMBB hydraulic retention time was 15 days. To assess the suitability of treated water in relation to vineyard irrigation, the effluent was physico-chemical analysed and direct toxicity bioassays with effluent matrix were carried out using Lepidium sativum L. seeds. The results showed the water quality required to be reutilised minimizing water consumption. This study will contribute for the implementation of an efficient water use plan...

Algal biomass production and wastewater treatment in high rate algal ponds receiving disinfected effluent

Santiago, Aníbal F.; Calijuri, Maria Lucia; Assemany, Paula P.; Calijuri, Maria do Carmo; Reis, Alberto
Fonte: Taylor & Francis Publicador: Taylor & Francis
Tipo: Artigo de Revista Científica
Publicado em //2013 Português
Relevância na Pesquisa
36.93%
Algal biomass production associated with wastewater is usually carried out in high rate algal ponds (HRAPs), which are concomitantly used in the treatment of such effluent. However, most types of wastewater have high levels of bacteria that can inhibit the growth of algal biomass by competing for space and nutrients. The objective of this study was to assess the influence of ultraviolet (UV) pre-disinfection on the performance of HRAPs used for wastewater treatment and algal biomass production. Two HRAPs were tested: one received effluent from an upflow anaerobic sludge blanket (UASB) reactor – HRAP – and the second received UASB effluent pre-disinfected by UV radiation – UVHRAP. Physical, chemical and microbiological parameters were monitored, as well as algal biomass productivity and daily pH and dissolved oxygen (DO) variation. The UVHRAP presented highest DO and pH values, as well as greater percentage of chlorophyll a in the biomass, which indicates greater algal biomass productivity. The average percentages of chlorophyll a found in the biomass obtained from the HRAP and the UVHRAP were 0.95±0.65% and 1.58±0.65%, respectively. However, total biomass productivity was greater in the HRAP (11.4 gVSS m-2 day-1) compared with the UVHRAP (9.3 gVSS m-2 day-1). Mean pH values were 7.7±0.7 in the HRAP and 8.1±1.0 in the UVHRAP...

Heat recovery from wastewater: numerical modelling of sewer systems

Silva, Ana Margarida Barradinhas da
Fonte: Faculdade de Ciências e Tecnologia Publicador: Faculdade de Ciências e Tecnologia
Tipo: info:eu-repo/semantics/masterthesis
Publicado em //2012 Português
Relevância na Pesquisa
36.93%
Dissertação para obtenção do Grau de Mestre em Engenharia do Ambiente, perfil Engenharia Sanitária; This thesis was carried as a collaboration of Delft University of Technology (TU Delft) and the companies Waternet and KWR. The main project aims to study the possibility of thermal energy recovery from wastewater, reducing the carbon dioxide (CO2) emissions linked to the energy sector. The present work is based on a previous computational model that was developed to simulate heat recovery from wastewater for constant flow rate and temperature of water. The first goal is to simulate a wastewater discharge. In order to achieve this, a Gaussian function was added to the boundary conditions for water flow rate and water temperature. As a second goal, this work aims to assess the significance of the terms present in the water heat balance and air heat balance equations. Binary coefficients were added in each term of both equations and then all the combinations were computed. The unsteady situation successfully simulated a main discharge and numerical predictions for water temperature and flow rate are presented. The deviations associated with the modified cases for the two equations suggest that the heat flux pipe to water (!!") and heat flux pipe to air (!!") terms are crucial for water and air heat balance predictions...

Aquaponics and its potential aquaculture wastewater treatment and human urine treatment

Sánchez, Henrique Junior Aiveca
Tipo: info:eu-repo/semantics/masterthesis
Publicado em /09/2014 Português
Relevância na Pesquisa
36.93%
The main objective of this thesis is to study the developing fields of aquaponics and its potential for aquaculture wastewater treatment and human urine treatment. Aquaponics is a food production system which combines fish farming (aquaculture) with soilless crop farming (hydroponics). In this thesis the concept of aquaponics and the underlying processes are explained. Research on aquaculture wastewater and human urine wastewater is reviewed and its potential application with aquaponic systems is studied. An overview of the different types of aquaponic systems and current research on the field is also presented. A case study was conducted in a farm in Askeröd, Sweden, which involved building two aquaponic systems (System 1 and System 2) and a human urine-based aquaponic system (System 3), with different degrees of component complexity and sizes. The design, building and monitoring of System 1, System 2 and System 3 was documented and described in detail. Four day experiments were conducted which tested the evolution in concentration of Total Ammonia Nitrogen (NH4+/NH3), Nitrite (NO2-), Nitrate (NO3-), Phosphate (PO43-), and Dissolved Oxygen (O2) after an initial nutrient input. The goal was to assess the concentrations of these parameters after four days and compare them with relevant literature examples in the aquaculture industry and in source-separated urine research. Neither of the two aquaponic systems (System 1 and System 2) displayed all of the parameter concentrations in the last day of testing below reference values found in literature. The best performing of the aquaponic systems was the more complex system (System 2) combining the hydroponic Nutrient Film Technique with a Deep Water Culture component...

The performance of a three-phase fluidized bed reactor in treatment of wastewater with high organic load

Souza,R. R.; Bresolin,I. T. L.; Bioni,T. L.; Gimenes,M. L.; Dias-Filho,B. P.
Fonte: Brazilian Society of Chemical Engineering Publicador: Brazilian Society of Chemical Engineering
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2004 Português
Relevância na Pesquisa
36.93%
An experimental study was carried out aiming to evaluate the performance of a three-phase fluidized bed bioreactor (FBBR) used to treat milk wastewater. In this study three different concentrations of milk wastewater substrate (462, 825 and 1473 mg O2/L) were tested. Using the same number of support particles, the results demonstrate that the average efficiency of COD removal decreased as the concentration of organic load in the substrate was increased. The growth of microorganism in the FBBR was followed by a count of viable cells in both liquid phase and the biofilms attached to the support. An increased number of viable cells were observed inside the reactor when it was used to degrade higher organic loads, with most of the cells on the support. The higher concentration of active biomass was responsible for achieving a relatively high absolute degradation of the wastewater containing the high organic load.

Anaerobic biodegradability of dairy wastewater pretreated with porcine pancreas lipase

Mendes,Adriano Aguiar; Pereira,Ernandes Benedito; Furigo Jr.,Agenor; Castro,Heizir Ferreira de
Fonte: Instituto de Tecnologia do Paraná - Tecpar Publicador: Instituto de Tecnologia do Paraná - Tecpar
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2010 Português
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Lipids-rich wastewater was partial hydrolyzed with porcine pancreas lipase and the efficiency of the enzymatic pretreatment was verified by the comparative biodegradability tests (crude and treated wastewater). Alternatively, simultaneous run was carried out in which hydrolysis and digestion was performed in the same reactor. Wastewater from dairy industries and low cost lipase preparation at two concentrations (0.05 and 0.5% w.v-1) were used. All the samples pretreated with enzyme showed a positive effect on organic matter removal (Chemical Oxygen Demand-COD) and formation of methane. The best results were obtained when hydrolysis and biodegradation were performed simultaneously, attaining high COD and color removal independent of the lipase concentration. The enzymatic treatment considerably improved the anaerobic operational conditions and the effluent quality (lower content of suspended solids and less turbidity). Thus, the use of enzymes such as lipase seemed to be a very promising alternative for treating the wastewaters having high fat and grease contents, such as those from the dairy industry.