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Tratamento de despejo de coqueria via nitritação/desnitritação operando um sistema de lodo ativado em bateladas sequenciais.; Coke-oven wastewater treatment over nitritation/denitritation in an activated sludge sequencing batch reactor.

Queiroz, Luciano Matos
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 19/06/2009 Português
Relevância na Pesquisa
27.04%
A presente pesquisa objetivou estudar a remoção dos poluentes presentes em uma água residuária de coqueria, através do processo biológico de nitritação/desnitritação operando um reator de lodo ativado em bateladas seqüenciais em duas etapas sucessivas. Durante a primeira, o reator foi alimentado com um efluente sintético composto por dois poluentes abundantes em despejos de coqueria: nitrogênio amoniacal (500 mg N/L) e fenol (1.000 mg C6H5OH/L). Na segunda, o reator foi alimentado com o despejo gerado na unidade de coqueria de uma indústria siderúrgica integrada. Ao longo da primeira etapa, ao final da fase aeróbia dos 28 ciclos de tratamento, foi possível alcançar eficiências de remoção de N-NH3 superiores a 90% com predominância do N-NO2 - na massa líquida do reator evidenciado pelas relações N-NO2 -/ (N-NO2 - + N-NO3 -) superiores a 86%. O principal mecanismo de inibição das bactérias oxidantes de nitrito (BON) foram concentrações de amônia livre no conteúdo do reator entre 3,2 e 19,5 mg NH3/L. As taxas específicas de nitritação variaram entre 0,03 e 0,11 kg N-NH3/ kg SSV.dia, para temperaturas no conteúdo do reator entre 15 e 34°C. Durante a fase anóxica, o fenol mostrou-se adequado como fonte de carbono para a biomassa desnitritante...

Degradação de surfactante aniônico em reator UASB com água residuária de lavanderia; Degradation of anionic surfactant in UASB reactor with laundry wastewater

Okada, Dagoberto Yukio
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 25/07/2012 Português
Relevância na Pesquisa
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Alquilbenzeno linear sulfonado (LAS) é um surfactante presente em água residuária de lavanderia. Em virtude da complexidade de sua degradação, o presente estudo envolveu a análise de alguns fatores, destacando-se: diversidade de co-substratos; tempo de detenção hidráulico (TDH); e concentração de co-substratos. Avaliou-se a degradação de LAS com diferentes co-substratos (metanol, etanol e extrato de levedura) em reator UASB, em TDH de 24 h e 14±2 mg/L de LAS. A influência de TDH e concentração de co-substratos foram analisadas em sete reatores UASB, com 12±3 mg/L de LAS; TDH de 6, 35 e 80 h, e diferentes concentrações de co-substratos (etanol, metanol e extrato de levedura), expressada pela carga orgânica específica (COE), entre 0,03 e 0,18 gDQO/gSTV.d. Ao final, avaliou-se a degradação de LAS em água residuária de lavanderia diluída, nessa mesma configuração de reator com TDH de 35 h e 10±5 mg/L de LAS. Em todos os ensaios foi utilizado inóculo granulado proveniente de reator UASB empregado no tratamento de água residuária de abatedouro de aves, mantendo-se intacta a forma granulada. No ensaio variando co-substratos, observou-se maior remoção de LAS (50%) na presença de co-substrato complexo (extrato de levedura) que na presença de metanol e etanol (29-41%). Diferença pouco significativa entre as comunidades do domínio Archaea e Bacteria (cerca de 60 e 40%...

Detecção Molecular de Giardia spp. em amostras de esgoto bruto provenientes do Estado de São Paulo e da cidade de Lima, Peru; Molecular detection of Giardia spp. in samples of raw wastewater from the State of São Paulo and the city of Lima, Peru.

Stanojlovic, Francisco Miroslav Ulloa
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 08/07/2014 Português
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Introdução Giardia intestinalis é um dos principais protozoários flagelados causadores de diarreia em humanos e animais, sendo um micro-organismo re-emergente, responsável por vários surtos de veiculação hídrica em nível mundial, razão pela qual tem merecido atenção das autoridades de Saúde Pública, e deve ser avaliado e monitorado, principalmente devido ao seu impacto negativo na qualidade do abastecimento público, em particular através do esgoto. Através de técnicas de biologia molecular é possível caracterizar e genotipar cistos presentes no esgoto, e identificar a circulação dos agrupamentos A e B, patogênicos para o homem. Neste estudo foram avaliadas amostras de esgoto bruto de cidades cosmopolitas da América Latina, no Estado de São Paulo, e em Lima, Peru. Objetivos Detectar através da técnica de reação em cadeia pela polimerase (PCR) a presença de G. intestinalis e os agrupamentos A e B, de importância para a saúde humana, em amostras de esgoto bruto provenientes do Estado de São Paulo, Brasil e de Lima, no Peru. Material e Métodos Um total de 18 amostras de esgoto bruto provenientes de portos, aeroportos e estações rodoviárias, com alto trânsito de pessoas de cinco municípios do estado de São Paulo foram coletadas pela técnica de Moore. Adicionalmente...

Potencial fitoremediador da Atriplex nummularia em solos salinizados e sodificados pelo reúso de efluentes de esgotos tratados na agricultura

Tavera Quiroz, Humberto Carlos
Tipo: dissertação Formato: application/pdf
Português
Relevância na Pesquisa
27.04%
O reúso de efluentes de esgotos domésticos na irrigação de culturas representa uma alternativa adequada na gestão dos recursos hídricos devido ao fornecimento de nutrientes e água em quantidades suficientes para o desenvolvimento das culturas, porém, também pode introduz impactos negativos ao solo, em parte, potencializados pela irrigação contínua ao longo do tempo. O maior efeito está relacionado com o aumento da salinidade e sodicidade. Uma alternativa para mitigar este impacto, é o uso de espécies vegetais extratoras e acumuladoras de sais que estão presentes no solo. Neste trabalho avaliaram-se as alterações nas propriedades químicas de um planossolo (disposto em 36 vasos, 18 isolados da chuva e dos ventos e 18 expostos a eventos climáticos) irrigado durante dois meses (junho-julho) com efluente de esgoto tratado por um reator UASB + lagoa de polimento. Posteriormente, avaliou-se o desempenho da espécie halófita Atriplex nummularia na remoção de sais e cátions acumulados no substrato (agosto 2008 – fevereiro 2009), monitorando o comportamento da condutividade elétrica, sódio, potássio, cálcio, magnésio e pH (no extrato do solo) e pH, condutividade elétrica e sódio trocável no percolado dos vasos. Durante a fitorremediação...

Processos de tratamento de efluentes aquosos : da compilação de tecnicas existentes a estudos de casos

Magno Schiavolin
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: dissertação de mestrado Formato: application/pdf
Publicado em 20/09/2001 Português
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Há sempre a necessidade da redução de gastos em várias etapas da indústria química e nas suas ramificações. No que diz respeito à minimização da geração de poluentes, há diversos processos de tratamento aplicados às correntes aquosas residuais, contudo os gastos para adequação destas correntes com a legislação vigente podem ser altos, de modo que é fundamental obter-se uma compreensão melhor dos processos de separação empregados nos tratamentos de tais correntes. Neste trabalho, dois sistemas foram estudados: fenol/água e etanol/água, onde ambos necessitam da adição de um solvente para promover a separação. O primeiro sistema é encontrado em diversos segmentos da indústria química e com concentrações variadas, necessitando de algum processo de separação para recuperar o fenol e possibilitar o descarte da corrente aquosa em um corpo receptor. O segundo sistema, etanol/água., está presente em destilarias de álcool, onde os processos de separação, que produzem correntes residuais aquosas, necessitam ser otimizados, minimizando a quantidade de solvente presente até atingir os limites aceitáveis ao meio ambiente. Três processos de separação foram abordados: extração líquido-líquido, destilação azeotrópica e destilação extrativa. Utilizou-se para isso o simulador comercial de processos HYSYS.Process (Hyprotech). Os solventes utilizados para promover a separação do sistema etanol/água foram: etilenoglicol...

Microbial Fuel Cells for autonomous systems : kinetics and technological advances in wastewater treatment and sensor applications

Peixoto, L.
Tipo: Tese de Doutorado
Publicado em 18/06/2012 Português
Relevância na Pesquisa
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Doctoral dissertation for PhD degree in Chemical and Biological Engineering; Microbial Fuel Cell (MFC) technology is a novel approach for the production of bioelectricity. In MFC, electroactive bacteria oxidize organic matter and have the particularity to transfer the electrons, directly to external electron acceptors producing electricity. Geobacter species are one of the most effective microorganisms known to use electrodes as the sole electron acceptor. In that regard, the present work was focused on the study of the parameters which influence the bacterial electron transfer process to electrodes and on the advancement of wastewater valorization and monitoring technologies based on the MFC concept. The electrochemical behavior of Geobacter sulfurreducens in different stages of the biofilm formation in MFC anodes was assessed by cyclic voltammetry in a three-electrode glass cells with two compartments separated by an ion exchange membrane at room temperature and 35 ºC. Cyclic voltammograms showed that the presence of G. sulfurreducens biofilm results in an increase of current intensities between - 0.5 V and 0.89 V vs. SCE with three well defined oxidation peaks at 0.16 V, 0.6 V and 0.8 V vs. SCE respectively. In mature biofilm the current intensity were higher. The current intensities for both cases were dependent on operating temperature (? 22 °C and 35ºC). In every stage of the biofilm formation...

Enantioselective Determination of Fluoxetine and Norfluoxetine in Wastewater

Ribeiro, Ana R.; Maia, Alexandra S.; Moreira, Irina S.; Afonso, Carlos; Castro, Paula M.L.; Tiritan, Maria E.
Tipo: Artigo de Revista Científica
Publicado em /06/2013 Português
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Microbial degradation of chiral compounds during wastewater treatment processes can be enantioselective and needs chiral analytical methodology to discriminate the biodegradation of both enantiomers. An enantioselective HPLC-FD method was developed and validated to monitor the degradation of fluoxetine (FLX) enantiomers by wastewater and the possible formation of its metabolite norfluoxetine (NFLX). The Solid Phase Extraction (SPE) of 50 mL of wastewater samples on 500 mg Oasis MCX cartridges was followed by the HPLC analysis using a Chirobiotic V chiral stationary phase under reversed mode. The developed method wasvalidated within the wastewater effluent used in microcosms laboratory assays. The chiral SPE-HPLC-FD method demonstrated to be selective, linear, sensitive, accurate and precise to quantify the enantiomers of FLX and of its metabolites NFLX in wastewaters. The limits of detection (0.8-2.0 ng mL -1 ) and quantification (2.0 – 4.0 ng mL -1 ) were adequate to monitoring the degradation assays at environmental level. The method proved to be robust to follow the biodegradation assays using real wastewater samplesspiked with FLX, during 46 days. To the best of our knowledge, this is the first reportof simultaneous separation of FLX and NFLX enantiomers using a Chirobiotic V and the application of the validated method to the enantioselective degradation by wastewater

Solid Phase Extraction of Fluoroquinolone Antibiotics from Wastewaters – Assessment of Different Commercial Sorbents

Maia, Alexandra S.; Ribeiro, Ana R.; Castro, Paula M.L.; Tiritan, Maria E.
Tipo: Artigo de Revista Científica
Publicado em /06/2013 Português
Relevância na Pesquisa
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Microbial degradation of fluorinated pharmaceuticalsduring wastewater treatment processes remains inadequate in most situations. Due to incomplete elimination, these residues are continually being introduced into the aquatic environments in which they settle throughout time since many of them are resistant to degradation. Fluoroquinolone antibiotics due to its persistence and implication on resistant-bacteria development, pose special interest in environmental analysis. Due to their zwitterionic characteristics, the extraction/pre-concentration process of fluoroquinolones prior analyses is an unquestionable challenge. This work compares the solid phase extraction efficiency of four fluoroquinolones (Ofloxacin, Norfloxacin, Ciprofloxacin and Moxifloxacin) from wastewater effluents by different commercial sorbents. Prior to wastewater analysis, preliminary tests were conducted in distilled water with a larger number of sorbents. Different experimental protocols and sorbents, namely OASIS® HLB, OASIS® WAX, OASIS® WCX (500 mg) and the molecularly imprinted polymer SupelMIP TM were applied to wastewater samples collected from a municipal wastewater treatment plant from the north of Portugal. The extracts were analyzed by a HPLC withFluorescence Detection validated method using a Luna PFP (2) 3µm column. Despite good results obtained with the molecularly imprinted polymer in distilled water...

Depuração de efluente suinícola por Lemna minor e valorização energética da biomassa por co-digestão anaeróbia

Pena, Luís Miguel Apolónia
Fonte: ISA/UL Publicador: ISA/UL
Tipo: info:eu-repo/semantics/masterthesis
Publicado em //2014 Português
Relevância na Pesquisa
27.04%
Mestrado em Engenharia do Ambiente - Instituto Superior de Agronomia; Over the last decades, phytodepuration has been considered an efficient technology to treat agricultural wastewaters. Swine wastewater is rich in nutrients that can be used to grow biomass, producing a treated wastewater that can be used for irrigation and a biomass that may be useful for potential energy production by anaerobic digestion (AD). In this study a comparative polishing treatment assays were developed, at a bench scale, through Lemna minor growth in swine wastewater (4%) with similar concentration at a real scale last lagoon and Lemna minor growth in synthetic medium. The highest observed growth rate obtained in swine wastewater was 28.7 ± 2.3 g m-2 day-1 or 3.1 ± 0.3 gDM m-2 day-1. The highest nitrogen and phosphorus uptake rates in swine wastewater system were 140 mg m-2 day-1 and 3.47 mg m- 2 day-1, respectively. The COD removal efficiency was 60.0 ± 1.0%. Furthermore, an integrated approach was investigated assessing possible valorisation of biomass by anaerobic co-digestion of swine wastewater with Lemna minor. Results showed a clear improvement in gas production rate and methane specific production in 40% and 44%, respectively, when compared to mono-substrate digestion

Increase in Bacterial Community Diversity in Subsurface Aquifers Receiving Livestock Wastewater Input

Cho, Jang-Cheon; Kim, Sang-Jong
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: text
Publicado em /03/2000 Português
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Despite intensive studies of microbial-community diversity, the questions of which kinds of microbial populations are associated with changes in community diversity have not yet been fully solved by molecular approaches. In this study, to investigate the impact of livestock wastewater on changes in the bacterial communities in groundwater, bacterial communities in subsurface aquifers were analyzed by characterizing their 16S rDNA sequences. The similarity coefficients of restriction fragment length polymorphism (RFLP) patterns of the cloned 16S ribosomal DNAs showed that the bacterial communities in livestock wastewater samples were more closely related to those in contaminated aquifer samples. In addition, calculations of community diversity clearly showed that bacterial communities in the livestock wastewater and the contaminated aquifer were much more diverse than those in the uncontaminated aquifer. Thus, the increase in bacterial-community diversity in the contaminated aquifer was assumed to be due to the infiltration of livestock wastewater, containing high concentrations of diverse microbial flora, into the aquifer. Phylogenetic analysis of the sequences from a subset of the RFLP patterns showed that the Cytophaga-Flexibacter-Bacteroides and low-G+C gram-positive groups originating from livestock wastewater were responsible for the change in the bacterial community in groundwater. This was evidenced by the occurrence of rumen-related sequences not only in the livestock wastewater samples but also in the contaminated-groundwater samples. Rumen-related sequences...

Monitoring Precursor 16S rRNAs of Acinetobacter spp. in Activated Sludge Wastewater Treatment Systems

Oerther, Daniel B.; Pernthaler, Jakob; Schramm, Andreas; Amann, Rudolf; Raskin, Lutgarde
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: text
Publicado em /05/2000 Português
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Recently, Cangelosi and Brabant used oligonucleotide probes targeting the precursor 16S rRNA of Escherichia coli to demonstrate that the levels of precursor rRNA were more sensitive to changes in growth phase than the levels of total rRNA (G. A. Cangelosi and W. H. Brabant, J. Bacteriol. 179:4457–4463, 1997). In order to measure changes in the levels of precursor rRNA in activated sludge systems, we designed oligonucleotide probes targeting the 3? region of the precursor 16S rRNA of Acinetobacter spp. We used these probes to monitor changes in the level of precursor 16S rRNA during batch growth of Acinetobacter spp. in Luria-Bertani (LB) medium, filtered wastewater, and in lab- and full-scale wastewater treatment systems. Consistent with the previous reports for E. coli, results obtained with membrane hybridizations and fluorescence in situ hybridizations with Acinetobacter calcoaceticus grown in LB medium showed a more substantial and faster increase in precursor 16S rRNA levels compared to the increase in total 16S rRNA levels during exponential growth. Diluting an overnight culture of A. calcoaceticus grown in LB medium with filtered wastewater resulted in a pattern of precursor 16S rRNA levels that appeared to follow diauxic growth. In addition...

Presence of human immunodeficiency virus nucleic acids in wastewater and their detection by polymerase chain reaction.

Ansari, S A; Farrah, S R; Chaudhry, G R
Tipo: text
Publicado em /12/1992 Português
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The human immunodeficiency virus type 1 (HIV-1) released by infected individuals or present in human and hospital wastes can potentially cause contamination problems. The presence of HIV-1 was investigated in 16 environmental samples, including raw wastewater, sludge, final effluent, soil, and pond water, collected from different locations. A method was developed to extract total nucleic acids in intact form directly from the raw samples or from the viral concentrates of the raw samples. The isolated nucleic acids were analyzed for the presence of HIV-1 by using in vitro amplification of the target sequences by the polymerase chain reaction (PCR) method. HIV-1-specific proviral DNA and viral RNA were detected in the extracted nucleic acids obtained from three wastewater samples by this method. The specificity of the PCR-amplified products was determined by Southern blot hybridization with an HIV-1-specific oligonucleotide probe, SK19. The isolated nucleic acids from wastewater samples were also screened for the presence of poliovirus type 1, representing a commonly found enteric virus, and simian immunodeficiency virus, representing, presumably, rare viruses. While poliovirus type 1 viral RNA was found in all of the wastewater samples...

Source Bioaerosol Concentration and rRNA Gene-Based Identification of Microorganisms Aerosolized at a Flood Irrigation Wastewater Reuse Site

Paez-Rubio, Tania; Viau, Emily; Romero-Hernandez, Socorro; Peccia, Jordan
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: text
Publicado em /02/2005 Português
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Reuse of partially treated domestic wastewater for agricultural irrigation is a growing practice in arid regions throughout the world. A field sampling campaign to determine bioaerosol concentration, culturability, and identity at various wind speeds was conducted at a flooded wastewater irrigation site in Mexicali, Baja California, Mexico. Direct fluorescent microscopy measurements for total microorganisms, culture-based assays for heterotrophs and gram-negative enteric bacteria, and small-subunit rRNA gene-based cloning were used for microbial characterizations of aerosols and effluent wastewater samples. Bioaerosol results were divided into two wind speed regimens: (i) below 1.9 m/s, average speed 0.5 m/s, and (ii) above 1.9 m/s, average speed 4.5 m/s. Average air-borne concentration of total microorganisms, culturable heterotrophs, and gram-negative enteric bacteria were, respectively, 1.1, 4.2, and 6.2 orders of magnitude greater during the high-wind-speed regimen. Small-subunit rRNA gene clone libraries processed from samples from air and the irrigation effluent wastewater during a high-wind sampling event indicate that the majority of air clone sequences were more than 98% similar to clone sequences retrieved from the effluent wastewater sample. Overall results indicate that wind is a potential aerosolization mechanism of viable wastewater microorganisms at flood irrigation sites.

Catalytic ozonation-biological coupled processes for the treatment of industrial wastewater containing refractory chlorinated nitroaromatic compounds*

Li, Bing-zhi; Xu, Xiang-yang; Zhu, Liang
Fonte: Zhejiang University Press Publicador: Zhejiang University Press
Tipo: text
Publicado em /03/2010 Português
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27.04%
A treatability study of industrial wastewater containing chlorinated nitroaromatic compounds (CNACs) by a catalytic ozonation process (COP) with a modified Mn/Co ceramic catalyst and an aerobic sequencing batch reactor (SBR) was investigated. A preliminary attempt to treat the diluted wastewater with a single SBR resulted in ineffective removal of the color, ammonia, total organic carbon (TOC) and chemical oxygen demand (COD). Next, COP was applied as a pretreatment in order to obtain a bio-compatible wastewater for SBR treatment in a second step. The effectiveness of the COP pretreatment was assessed by evaluating wastewater biodegradability enhancement (the ratio of biology oxygen demand after 5 d (BOD5) to COD), as well as monitoring the evolution of TOC, carbon oxidation state (COS), average oxidation state (AOS), color, and major pollutant concentrations with reaction time. In the COP, the catalyst preserved its catalytic properties even after 70 reuse cycles, exhibiting good durability and stability. The performance of SBR to treat COP effluent was also examined. At an organic loading rate of 2.0 kg COD/(m3·d), with hydraulic retention time (HRT)=10 h and temperature (30±2) °C, the average removal efficiencies of NH3-N, COD...

Assessment of the Interactions between Economic Growth and Industrial Wastewater Discharges Using Co-integration Analysis: A Case Study for China’s Hunan Province

Xiao, Qiang; Gao, Yang; Hu, Dan; Tan, Hong; Wang, Tianxiang
Fonte: Molecular Diversity Preservation International (MDPI) Publicador: Molecular Diversity Preservation International (MDPI)
Tipo: text
Português
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We have investigated the interactions between economic growth and industrial wastewater discharge from 1978 to 2007 in China’s Hunan Province using co-integration theory and an error-correction model. Two main economic growth indicators and four representative industrial wastewater pollutants were selected to demonstrate the interaction mechanism. We found a long-term equilibrium relationship between economic growth and the discharge of industrial pollutants in wastewater between 1978 and 2007 in Hunan Province. The error-correction mechanism prevented the variable expansion for long-term relationship at quantity and scale, and the size of the error-correction parameters reflected short-term adjustments that deviate from the long-term equilibrium. When economic growth changes within a short term, the discharge of pollutants will constrain growth because the values of the parameters in the short-term equation are smaller than those in the long-term co-integrated regression equation, indicating that a remarkable long-term influence of economic growth on the discharge of industrial wastewater pollutants and that increasing pollutant discharge constrained economic growth. Economic growth is the main driving factor that affects the discharge of industrial wastewater pollutants in Hunan Province. On the other hand...

Study of Physico-Chemical Characteristics of Wastewater in an Urban Agglomeration in Romania

Popa, Paula; Timofti, Mihaela; Voiculescu, Mirela; Dragan, Silvia; Trif, Catalin; Georgescu, Lucian P.
Fonte: The Scientific World Journal Publicador: The Scientific World Journal
Tipo: text
Publicado em 01/08/2012 Português
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This study investigates the level of wastewater pollution by analyzing its chemical characteristics at five wastewater collectors. Samples are collected before they discharge into the Danube during a monitoring campaign of two weeks. Organic and inorganic compounds, heavy metals, and biogenic compounds have been analyzed using potentiometric and spectrophotometric methods. Experimental results show that the quality of wastewater varies from site to site and it greatly depends on the origin of the wastewater. Correlation analysis was used in order to identify possible relationships between concentrations of various analyzed parameters, which could be used in selecting the appropriate method for wastewater treatment to be implemented at wastewater plants.

Wastewater use in algae production for generation of renewable resources: a review and preliminary results

Dalrymple, Omatoyo K; Halfhide, Trina; Udom, Innocent; Gilles, Benjamin; Wolan, John; Zhang, Qiong; Ergas, Sarina
Fonte: BioMed Central Publicador: BioMed Central
Tipo: text
Publicado em 05/01/2013 Português
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Microalgae feedstock production can be integrated with wastewater and industrial sources of carbon dioxide. This study reviews the literature on algae grown on wastewater and includes a preliminary analysis of algal production based on anaerobic digestion sludge centrate from the Howard F. Curren Advanced Wastewater Treatment Plant (HFC AWTP) in Tampa, Florida and secondary effluent from the City of Lakeland wastewater treatment facilities in Lakeland, Florida. It was demonstrated that a mixed culture of wild algae species could successfully be grown on wastewater nutrients and potentially scaled to commercial production. Algae have demonstrated the ability to naturally colonize low-nutrient effluent water in a wetland treatment system utilized by the City of Lakeland. The results from these experiments show that the algae grown in high strength wastewater from the HFC AWTP are light-limited when cultivated indoor since more than 50% of the outdoor illumination is attenuated in the greenhouse.

Eutrophication and Bacterial Pathogens as Risk Factors for Avian Botulism Outbreaks in Wetlands Receiving Effluents from Urban Wastewater Treatment Plants

Anza, Ibone; Vidal, Dolors; Laguna, Celia; Díaz-Sánchez, Sandra; Sánchez, Sergio; Chicote, Álvaro; Florín, Máximo; Mateo, Rafael
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: text
Publicado em /07/2014 Português
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Due to the scarcity of water resources in the “Mancha Húmeda” Biosphere Reserve, the use of treated wastewater has been proposed as a solution for the conservation of natural threatened floodplain wetlands. In addition, wastewater treatment plants of many villages pour their effluent into nearby natural lakes. We hypothesized that certain avian pathogens present in wastewater may cause avian mortalities which would trigger avian botulism outbreaks. With the aim of testing our hypothesis, 24 locations distributed in three wetlands, two that receive wastewater effluents and one serving as a control, were monitored during a year. Sediment, water, water bird feces, and invertebrates were collected for the detection of putative avian pathogenic Escherichia coli (APEC), Salmonella spp., Clostridium perfringens type A, and Clostridium botulinum type C/D. Also, water and sediment physicochemical properties were determined. Overall, APEC, C. perfringens, and C. botulinum were significantly more prevalent in samples belonging to the wetlands which receive wastewater. The occurrence of a botulism outbreak in one of the studied wetlands coincided with high water temperatures and sediment 5-day biochemical oxygen demand (BOD5), a decrease in water redox potential...

Comparative Studies of Oleaginous Fungal Strains (Mucor circinelloides and Trichoderma reesei) for Effective Wastewater Treatment and Bio-Oil Production

Bhanja, Anshuman; Minde, Gauri; Magdum, Sandip; Kalyanraman, V.
Fonte: Hindawi Publishing Corporation Publicador: Hindawi Publishing Corporation
Tipo: text
Português
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Biological wastewater treatment typically requires the use of bacteria for degradation of carbonaceous and nitrogenous compounds present in wastewater. The high lipid containing biomass can be used to extract oil and the contents can be termed as bio-oil (or biodiesel or myco-diesel after transesterification). The separate experiments were conducted on actual wastewater samples with 5%?v/v inoculum of Mucor circinelloides MTCC1297 and Trichoderma reesei NCIM992 strains. The observed reductions in chemical oxygen demand (COD) were 88.72% and 86.75% in 96?hrs and the observed substrate based biomass yields were 0.21?mg VSS/mg COD and 0.22?mg VSS/mg COD for M. circinelloides reactor and for T. reesei reactor, respectively. The resulted bio-oil production from wastewater treatment by M. circinelloides and T. reesei reactors was 142.2?mg/L and 74.1?mg/L, whereas biomass containing bio-oil contents (%w/w) were 22.11% and 9.82%, respectively. In this experiment, the fungal wastewater treatment was also compared with conventional bacterial process with respect to specific growth rate, biomass production, and oil content. This study suggests that wastewater can be used as a potential feedstock for bio-oil production with the use of oleaginous fungal strains and which could be a possible route of waste to energy.

Wastewater treatment in Las Vegas, Santa Barbara, Honduras

Hodge, Matthew M
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: thesis Formato: 62 leaves
Português
Relevância na Pesquisa
27.08%
The Municipality of Las Vegas, Honduras is located immediately to the west of Lake Yojoa, the largest inland lake in Honduras. Beginning in 2005, the Massachusetts Institute of Technology (MIT) began working with stakeholders around the lake to assess anthropogenic environmental impacts on the lake. In January 2008, a technical team composed of Dr. Eric Adams from MIT, Aridai Herrera a civil engineer from Malcolm Pirnie, and MIT students Anne Mikelonis and Matthew Hodge, traveled to Las Vegas to work with the Municipality on domestic wastewater discharge, one of the previously identified environmental impacts on Lake Yojoa. In preliminary discussions with the Municipality, the team identified three goals for the project: evaluate the performance of the existing wastewater treatment facility, test the possibility of enhancements to this facility, and evaluate options for expanded sewerage and wastewater treatment throughout Las Vegas. The results of this project are a set of three recommendations for the Municipality to improve wastewater treatment. First, regular maintenance of existing facilities is necessary to achieve optimal performance for existing wastewater infrastructure. Second, substantial non-waste water is entering the sewerage leading to an average daily flow of 1...