Página 1 dos resultados de 579 itens digitais encontrados em 0.012 segundos

Full-scale anaerobic sequencing batch biofilm reactor for sulfate-rich wastewater treatment

SARTI, Arnaldo; SILVA, Ariovaldo J.; ZAIAT, Marcelo; FORESTI, Eugenio
Fonte: DESALINATION PUBL Publicador: DESALINATION PUBL
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
56.29%
This paper describes the performance and biofilm characteristics of a full-scale anaerobic sequencing batch biofilm reactor (ASBBR; 20 m(3)) containing biomass immobilized on an inert support (mineral coal) for the treatment of industrial wastewater containing a high sulfate concentration. The ASBBR reactor was operated during 110 cycles (48 h each) at sulfate loading rates ranging from 6.9 to 62.4 kgSO(4)(2-)/cycle corresponding to sulfate concentrations of 0.58-5.2 gSO(4)(2-)/L. Domestic sewage and ethanol were utilized as electron donors for sulfate reduction. After 71 cycles the mean sulfate removal efficiency was 99%, demonstrating a high potential for biological sulfate reduction. The biofilm formed in the reactor occurred in two different patterns, one at the beginning of the colonization and the other of a mature biofilm. These different colonization patterns are due to the low adhesion of the microorganisms on the inert support in the start-up period. The biofilm population is mainly made up of syntrophic consortia among sulfate-reducing bacteria and methanogenic archaea such as Methanosaeta spp.; Fundacao de Amparo a Pesquisa do Estado de Sao Paulo-FAPESP[03/07799-2]; Conselho Nacional de Desenvolvimento Cientifico e Tecnolgico-CNPq[019/2004]; Conselho Nacional de Desenvolvimento Cientifico e Tecnolgico-CNPq[478355/2004-1]

The treatment of sulfate-rich wastewater using an anaerobic sequencing batch biofilm pilot-scale reactor

SARTI, Arnaldo; SILVA, Ariovaldo J.; ZAIAT, Marcelo; FORESTI, Eugenio
Fonte: ELSEVIER SCIENCE BV Publicador: ELSEVIER SCIENCE BV
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
56.29%
This paper presents the results from 92 cycles of an anaerobic sequencing batch biofilm reactor containing biomass immobilized on inert support (mineral coal) applied for the treatment of an industrial wastewater containing high sulfate concentration. The pilot-scale reactor, with a total volume of 1.2 m(3), was operated at sulfate loading rates ranging from 0.15 to 1.90 kgSO(4)(2-)/cycle (48 It - cycle) corresponding to sulfate concentrations of 0.25 to 3.0 gSO(4)(2-) l(-1). Domestic sewage and ethanol were utilized as electron donors for sulfate reduction. Influent sulfate concentrations were increased in order to evaluate the minimum COD/sulfate ratio at which high reactor performance could be maintained. The mean sulfate removal efficiency remained between the range of 88 to 92% at several sulfate concentrations. Temporal profiles along the 48 h cycles were carried out under stable operation at sulfate concentrations of 1.0, 2.0 and 3.0 gSO(4)(2-) l(-1). Sulfate removal reached 99% for cycle times of 15, 25, and 30 h, and the effluents sulfate concentrations were lower than 8 mgSO(4)(2-) l(-1). The results demonstrate the potential applicability of the anaerobic configuration for the biological treatment of sulfate-rich wastewaters. (C) 2009 Elsevier B.V. All rights reserved.; Fundacao de Amparo a Pesquisa do Estado de Sao Paulo-FAPESP[03/07799-2]; Conselho Nacional de Desenvolvimento Cientifico e Tecnologico-CNPq[019/2004]; Conselho Nacional de Desenvolvimento Cientifico e Tecnologico-CNPq[478355/2004-1]

Anaerobic treatment of sulfate-rich wastewater in an anaerobic sequential batch reactor (AnSBR) using butanol as the carbon source

SARTI, Arnaldo; ZAIAT, Marcelo
Fonte: ACADEMIC PRESS LTD- ELSEVIER SCIENCE LTD Publicador: ACADEMIC PRESS LTD- ELSEVIER SCIENCE LTD
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
56.29%
Biological sulfate reduction was studied in a laboratory-scale anaerobic sequential batch reactor (14 L) containing mineral coal for biomass attachment. The reactor was fed industrial wastewater with increasingly high sulfate concentrations to establish its application limits. Special attention was paid to the use of butanol in the sulfate reduction that originated from melamine resin production. This product was used as the main organic amendment to support the biological process. The reactor was operated for 65 cycles (48 h each) at sulfate loading rates ranging from 2.2 to 23.8 g SO(4)(2-)/cycle, which corresponds to sulfate concentrations of 0.25, 0.5,1.0, 2.0 and 3.0 g SW(4)(2-)L(-1). The sulfate removal efficiency reached 99% at concentrations of 0.25, 0.5 and 1.0 g SO(4)(2-)L(-1). At higher sulfate concentrations (2.0 and 3.0 g SO(4)(2-)L(-1)), the sulfate conversion remained in the range of 71-95%. The results demonstrate the potential applicability of butanol as the carbon source for the biological treatment of sulfate in an anaerobic batch reactor. (C) 2011 Elsevier Ltd. All rights reserved.; FAPESP-Fundacao de Amparo a Pesquisa do Estado de Sao Paulo, Brazil[07/08335-0]

Application of Electrochemical Degradation of Wastewater Composed of Mixtures of Phenol-Formaldehyde

Fornazari, Ana Luiza T.; Malpass, Geoffroy R. P.; Miwa, Douglas Waychi; Motheo, Artur de Jesus
Fonte: SPRINGER; DORDRECHT Publicador: SPRINGER; DORDRECHT
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
56.35%
The industrial wastewater from resin production plants contains as major components phenol and formaldehyde, which are traditionally treated by biological methods. As a possible alternative method, electrochemical treatment was tested using solutions containing a mixture of phenol and formaldehyde simulating an industrial effluent. The anode used was a dimensionally stable anode (DSAA (R)) of nominal composition Ti/Ru0.3Ti0.7O2, and the solution composition during the degradation process was analyzed by liquid chromatography and the removal of total organic carbon. From cyclic voltammetry, it is observed that for formaldehyde, a small offset of the beginning of the oxygen evolution reaction occurs, but for phenol, the reaction is inhibited and the current density decreases. From the electrochemical degradations, it was determined that 40 mA cm(-2) is the most efficient current density and the comparison of different supporting electrolytes (Na2SO4, NaNO3, and NaCl) indicated a higher removal of total organic carbon in NaCl medium.; Brazilian National Council for Scientific and Technological Development (CNPq); Brazilian National Council for Scientific and Technological Development (CNPq)

Uso da técnica produção mais limpa em estação de tratamento de efluentes industriais.; Use of cleaner production methodology in industrial wastewater treatment plants (WTP).

Harada, Franco Hamilton
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 11/05/2006 Português
Relevância na Pesquisa
56.45%
Inserção da metodologia de Produção Mais Limpa em Estações de Tratamento de Efluentes (ETE) de indústrias no geral. O conceito fornecido pela Produção Mais Limpa permite sua aplicação aos tratamentos de fim de tubo, não se restringindo somente ao processo produtivo. A aplicação desta ferramenta visa um incremento e a melhoria contínua do sistema de gestão ambiental englobando o tratamento de todo o tipo de poluição gerada, especificamente neste trabalho, os efluentes industriais. As ETE, com um gerenciamento e operação adequados, além de minimizarem os efeitos poluidores dos efluentes gerados nas indústrias a níveis exigidos pela legislação aplicável ou a padrões de qualidade requeridos internamente em seu processo, podem controlar todo o processo produtivo interno a fábrica. Há a possibilidade de através dos diversos parâmetros processuais de controle detectar grande parte dos desvios produtivos ocorridos no interior da fábrica. Com a aplicação da ferramenta de Produção Mais Limpa em Estações de Tratamento de Efluentes Industriais, demonstra-se através de suas diversas metodologias: - A melhoria contínua em todos os processos produtivos e de tratamento de efluentes envolvidos na indústria; - O aumento progressivo das eficiências processuais; - Que investimentos e meio ambiente estão fortemente atrelados para o desenvolvimento da indústria e seu fortalecimento tanto a nível comercial quanto na sociedade. Portanto...

Estratégias de operação de reatores aeróbio/anóxico operados em batelada sequencial para remoção de nitrogênio de água residuária industrial; Strategies of operation of aerobic/anoxic sequential batch reactors for industrial wastewater nitrogen removal

Ono, Alexandre Fernandes
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 27/07/2007 Português
Relevância na Pesquisa
56.33%
A pesquisa propôs avaliar o desempenho e o comportamento de reatores seqüenciais em batelada com biomassa suspensa e imobilizada, em escala de bancada, na remoção de compostos de nitrogênio. Tais sistemas foram testados como tratamento complementar de reatores sulfetogênico e metanogênico utilizados no tratamento de água residuária industrial com alta concentração de sulfato e amônia. Visou o desenvolvimento de uma estratégia de operação que viabilizasse o uso dos próprios constituintes da água residuária para a maximização da eficiência do tratamento. O estudo foi dividido em 3 etapas principais. Na etapa 1 (181 dias de operação), o reator com biomassa suspensa foi mantido com 4 fases alternadas aeróbio/anóxico e ciclo de 24 horas, e verificou-se a presença da desnitrificação endógena (eficiência de remoção de nitrogênio de 65 '+ OU -' 27%). Para a etapa 2 (127 dias de operação), o reator de biomassa suspensa foi submetido ao tempo de ciclo de 12 horas, com uma fase aeróbia (6 horas) e com posterior fase anóxica (6 horas). Nessa etapa adicionou-se efluentes dos reatores metanogênico e sulfetogênico, ricos em ácidos voláteis (ácido acético), com intuito de acelerar o processo desnitrificante. Os resultados obtidos foram baixos em termos de remoção de nitrogênio (42 '+ OU -' 21%). Para a etapa 3 (134 dias de operação)...

Tratamento de efluentes industriais mediante a aplicação de argila organifílica e carvão ativado granular.; Industrial wastewater treatment through the use of granular organoclay and granular activated carbon.

Waelkens, Barbara Elisabeth
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 16/04/2010 Português
Relevância na Pesquisa
56.45%
A presença do óleo pode trazer graves problemas ambientais quando lançado em corpos dágua. A remoção de óleos e graxas de efluentes industriais, principalmente quando na forma emulsificada ainda é um desafio para o tratamento de efluentes industriais. Argilas quimicamente modificadas com sais quaternários de amônio podem ser uma alternativa para o tratamento de efluentes oleosos por apresentarem características organofílicas, podendo desta forma ser utilizadas como material adsorptivo. O presente trabalho estuda a aplicabilidade de uma argila organofílica granular, seja de forma simples ou em combinação com carvão ativado granular, como meio filtrante para a remoção de óleos e graxas de dois efluentes industriais reais oriundos de uma indústria de laminação a frio e uma indústria automobilística. Ambos os efluentes apresentam concentrações baixas de óleos e graxas, variando entre 5 e 30 mg/l de óleos e graxas, entretanto, estes valores não estão sempre em concordância com a legislação vigente. A análise gravimétrica de óleos e graxas não forneceu dados confiáveis, entretanto, foi possível observar uma redução da concentração de carbono orgânico total (COT) após o tratamento com a argila organofílica granular. A redução da concentração de COT foi ainda maior após o tratamento do efluente com a composição Argila Organofílica Granular seguida de Carvão Ativado Granular. Tal composição é a mais recomendada...

Electrochemical oxidation of wastewater containing aromatic amines using a flow electrolytic reactor

Moraes, Peterson B.; Bertazzoli, Rodnei; Bidoia, Ederio Dino
Tipo: Artigo de Revista Científica Formato: 1-14
Português
Relevância na Pesquisa
46.58%
Aromatic amines are environmental pollutants and represent one of the most important classes of industrial and natural chemicals. Some types of complex effluents containing these chemical species, mainly those originated from chemicals plants are not fully efficiently treated by conventional processes. In this work, the use of electrochemical technology through an electrolytic pilot scale flow reactor is considered for treatment of wastewater of a chemical industry manufacturer of antioxidant and anti-ozonant substances used in rubber. Experimental results showed that was possible to remove between 65% and 95% of apparent colour and chemical oxygen demand removal between 30 and 90% in 60 min of treatment, with energy consumption rate from 26 kWh m-3 to 31 kWh m-3. Absorbance, total organic carbon and toxicity analyses resulted in no formation of toxic by-products. The results suggest that the presented electrochemical process is a suitable method for treating this type of wastewater, mainly when pre-treated by aeration. Copyright © 2013 Inderscience Enterprises Ltd.

Avaliação e identificação de toxicidade em efluente da fabricação de resinas de poliester.; Toxicity identification evaluation of polyester resin manufacturing wastewater.

Roberto Augusto Caffaro Filho
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 05/06/2008 Português
Relevância na Pesquisa
46.61%
Os processos industriais são geradores de uma ampla variedade de contaminantes que estão presentes nas águas residuarias. A seleção de processos de tratamento baseia-se nas características do efluente a ser tratado. Neste trabalho investigou-se um efluente tóxico da fabricação de resinas de poliéster. Existem poucas informações na literatura sobre este tipo de água residuaria. Procedeu-se a caracterização do efluente, efetuando-se a avaliação e identificação de constituintes tóxicos presentes no mesmo por meio de uma abordagem orientada por toxicidade. Foi utilizado bioensaio respirometrico em lodo ativado para avaliar a toxicidade do efluente bruto. Então, foram efetuados tratamentos físicos e químicos para fracionamento do efluente, e apos cada um deles, realizou-se o mesmo bioensaio. Dessa maneira, avaliou-se qual técnica de fracionamento foi a mais efetiva na redução da toxicidade. A maior redução de toxicidade foi observada apos o fracionamento do efluente por arraste com ar em pH 11 (62,5 %). Este resultado demonstrou que uma fração significativa da toxicidade do efluente para lodos ativados era causada por compostos orgânicos volatilizados em pH 11. Isso indica que o tratamento do efluente por arraste com ar em pH básico pode ter impacto positivo em um tratamento biológico aeróbio subseqüente. Uma vez determinado o tipo de compostos no efluente que provocam efeitos tóxicos (Compostos Organicos Volateis - COVs)...

Development of the Inverted anaerobic sludge blanket reactor : a novel technology for the treatment of industrial wastewater containing fat

Picavet, M. A.
Tipo: Tese de Doutorado
Publicado em 16/04/2012 Português
Relevância na Pesquisa
46.55%
Tese de doutoramento em Engenharia Química e Biológica; Lipids are ubiquitous in industrial wastewater produced in the food industry, yet practically no biological treatment systems are available on the market that are capable of directly treating wastewater containing lipids. In general, lipids are considered a nuisance and are normally removed prior to biological treatment. Lipids are however compounds with a high calorific value and therefore highly interesting for conversion into biogas under anaerobic conditions. This thesis reports on the development of a high-rate anaerobic reactor capable of directly treating wastewater containing fat. The reactor’s technological basis for includes floatation as main sludge retention technique. Next to that, the specific contact surface between sludge and fat is maximised to prevent mass transfer limitation. Because fat degradation leads again to settlable sludge, a sedimentation step is incorporated in the form of a tilted plate separator (TPS). The settled sludge is then recycled and mixed up with raw wastewater to stimulate fat adsorption and sludge floatation. The sludge/raw wastewater mixture is subsequently injected into downers to induce reactor mixing and the break-up of floating sludge. Finally...

Substrate effect on bacterial communities from constructed wetlands planted with Typha latifolia treating industrial wastewater

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
56.42%
Constructed wetlands (CWs) have been recognized as being able to effectively treat wastewater from municipal and industrial sources. This study focused on the effect of different substrates and long-term operation of horizontal subsurface flowCWstreating tannery wastewater on the bacterial communities. The CWs were planted with Typha latifolia in three types of substrate: two units with different types of expanded clay aggregates and one unit with fine gravel. Another unit with expanded clay was left unvegetated. Changes in the bacterial community related to the type of substrate, different hydraulic loading rates and along CW operationwere examined using denaturating gradient gel electrophoresis (DGGE). Bacterial enumerationwas also performed and several bacterial isolateswere retrieved from the CWs. Phylogenetic affiliations of those isolates were obtained on the basis of 16S rRNA gene sequences and revealed that they were closely related to the genera Bacillus (TM1S1, TM1R3, TNR1 and TAR1), Paracoccus (TM1R2), Pseudomonas (TM1R1) and Halomonas (TM1S2). The type of substrate and the presence of T. latifolia had a major effect on the species richness and the structure of bacterial communities as inferred by numerical analysis of DGGE profiles.

Treatment of industrial wastewater with two-stage constructed wetlands planted with typha latifolia and phragmites australis

Calheiros, Cristina S.C.; 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
66.52%
Industrial wastewater treatment comprises several processes to fulfill the discharge permits or to enable the reuse of wastewater. For tannery wastewater, constructed wetlands (CWs) may be an interesting treatment option. Two-stage series of horizontal subsurface flow CWs with Phragmites australis (UP series) and Typha latifolia (UT series) provided high removal of organics from tannery wastewater, up to 88% of biochemical oxygen demand (BOD5) (from an inlet of 420 to 1000 mg L-1) and 92% of chemical oxygen demand (COD) (from an inlet of 808 to 2449 mg L-1), and of other contaminants, such as nitrogen, operating at hydraulic retention times of 2, 5 and 7 days. No significant (P < 0.05) differences in performance were found between both the series. Overall mass removals of up to 1294 kg COD ha-1 d-1 and 529 kg BOD5 h-1 d-1 were achieved for a loading ranging from 242 to 1925 kg COD ha-1 d-1 and from 126 to 900 kg BOD5 ha-1 d-1. Plants were resilient to the conditions imposed, however P. australis exceeded T. latifolia in terms of propagation.

Assessment of surface water in two Amazonian rivers impacted by industrial wastewater, Barcarena City, Pará State (Brazil)

Lima,Marcelo de O.; Santos,Elisabeth C. O.; Jesus,Iracina M. de; Medeiros,Adaelson C.; Faial,Kelson do C. F.; Alves,Cláudio N.
Fonte: Sociedade Brasileira de Química Publicador: Sociedade Brasileira de Química
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/08/2011 Português
Relevância na Pesquisa
66.42%
In 2007, surface waters were collected from 21 sampling points in Barcarena City in Northern Region of Brazil: one sampling point located in a stream that receives discharge of wastewater from a kaolin processing industry and flows into the Curuperê River, three sampling points located near sources that emerge on the left bank and flow into the Curuperê River, nine sampling points in Curuperê River, which flows into the Dendê River, and eight in Dendê River, a tributary on the right bank of the Pará River. For all water samples were quantified 14 physicochemical variables and levels of 12 metals. The results in the points near the sources of the Curuperê River presented physicochemical profile and metal levels which are typical of surface waters being used as reference to compare and identify possible changes in the chemical characteristics of the other sampling points. The comparison between the results obtained for the sources of the Curuperê River and the ones for the point near the discharge of industrial wastewater revealed strong changes in the values of 6 physicochemical variables (pH, electrical conductivity (EC), total dissolved solids (TDS), sulfate (SO4), ammoniacal nitrogen (NH4-N) and salinity) and an increase in magnitude of the levels of four metals (Al...

Degradation of organic pollutants and characteristics of activated sludge in an anaerobic/anoxic/oxic reactor treating chemical industrial wastewater

Wang,Dong; Ji,Min; Wang,Can
Fonte: Brazilian Society of Chemical Engineering Publicador: Brazilian Society of Chemical Engineering
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/09/2014 Português
Relevância na Pesquisa
66.42%
A laboratory-scale anaerobic/anoxic/oxic system operated at the hydraulic retention times (HRT) of 20, 40, and 60 h with mixed liquor suspended solids (MLSS) concentrations of 3 g/L and 6 g/L was considered for treating chemical industrial wastewater rich in complex organic compounds and total dissolved solids. Extending the HRT and increasing the MLSS concentration resulted in higher removal efficiency for chemical oxygen demand at 72%. Organic compounds in wastewater could be classified into easily-removed and refractory compounds during treatment. The easily-removed compounds consisted primarily of ethers, alcohols, and aldehydes, whereas the refractory compounds included mainly oxygen-containing heterocyclic and benzene-containing compounds. Results from energy-dispersive X-ray spectroscopy showed that several metal ions accumulated in activated sludge, particularly Fe(III). Fe accumulated mainly on the surface of sludge floc pellets and resulted in the compactness of activated sludge, which caused the values of mixed liquor volatile suspended solids /MLSS and sludge volume index to decrease.

Alterations in proteins and amino acids of the Nile cyanobacteria Pseudanabaena limnetica and Anabaena wisconsinense in response to industrial wastewater pollution

El-Sheekh,Mostafa Mohamed; El-Otify,Ahmed Mohamed; Saber,Hani
Fonte: Instituto de Tecnologia do Paraná - Tecpar Publicador: Instituto de Tecnologia do Paraná - Tecpar
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/08/2011 Português
Relevância na Pesquisa
56.52%
The effect of industrial wastewater on the Nile cyanobacteria Pseudanabaena limnetica and Anabaena wisconsinense was investigated. The data showed that P. limnetica was more sensitive to pollution than A. wisconsinense. The treatments with different levels of wastewater exerted pronounced reductions in protein and amino acids content. SDS-PAGE analysis revealed that the cyanobacteria grown in the industrial wastewater showed induction in the synthesis of certain polypeptides and repression of others. The treatments of P. limnetica with wastewater stimulated the appearance of six protein bands with molecular masses of 28, 30, 31, 32, 58 and 97 kDa. The same treatments caused the disappearance of 20, 38 and 56 kDa. The structural protein pattern of the treated A. wisconsinense showed appearance of 16, 30, 170 and 230 kDa and disappearance of 56 kDa. The treatment of the two investigated cyanobacteria with different levels of wastewater stimulated the biosyntheses of different amino acids and inhibited others.

Long-term surveillance of sulfate-reducing bacteria in highly saline industrial wastewater evaporation ponds

Ben-Dov, Eitan; Kushmaro, Ariel; Brenner, Asher
Fonte: BioMed Central Publicador: BioMed Central
Tipo: text
Publicado em 18/02/2009 Português
Relevância na Pesquisa
46.5%
Abundance and seasonal dynamics of sulfate-reducing bacteria (SRB), in general, and of extreme halophilic SRB (belonging to Desulfocella halophila) in particular, were examined in highly saline industrial wastewater evaporation ponds over a forty one month period. Industrial wastewater was sampled and the presence of SRB was determined by quantitative real-time PCR (qPCR) with a set of primers designed to amplify the dissimilatory sulfite reductase (dsrA) gene. SRB displayed higher abundance during the summer (106–108 targets ml-1) and lower abundance from the autumn-spring (103–105 targets ml-1). However, addition of concentrated dissolved organic matter into the evaporation ponds during winter immediately resulted in a proliferation of SRB, despite the lower wastewater temperature (12–14°C). These results indicate that the qPCR approach can be used for rapid measurement of SRB to provide valuable information about the abundance of SRB in harsh environments, such as highly saline industrial wastewaters. Low level of H2S has been maintained over five years, which indicates a possible inhibition of SRB activity, following artificial salination (?16% w/v of NaCl) of wastewater evaporation ponds, despite SRB reproduction being detected by qPCR.

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
Relevância na Pesquisa
46.55%
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
Relevância na Pesquisa
46.61%
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...

Combined Industrial Wastewater Treatment in Anaerobic Bioreactor Posttreated in Constructed Wetland

Zeb, Bibi Saima; Mahmood, Qaisar; Jadoon, Saima; Pervez, Arshid; Irshad, Muhammad; Bilal, Muhammad; Bhatti, Zulfiqar Ahmad
Fonte: Hindawi Publishing Corporation Publicador: Hindawi Publishing Corporation
Tipo: text
Português
Relevância na Pesquisa
46.58%
Constructed wetland (CW) with monoculture of Arundo donax L. was investigated for the posttreatment of anaerobic bioreactor (ABR) treating combined industrial wastewater. Different dilutions of combined industrial wastewater (20, 40, 60, and 80) and original wastewater were fed into the ABR and then posttreated by the laboratory scale CW. The respective removal efficiencies of COD, BOD, TSS, nitrates, and ammonia were 80%, 78–82%, 91.7%, 88–92%, and 100% for original industrial wastewater treated in ABR. ABR was efficient in the removal of Ni, Pb, and Cd with removal efficiencies in the order of Cd (2.7%) > Ni (79%) > Pb (85%). Posttreatment of the ABR treated effluent was carried out in lab scale CW containing A. donax L. CW was effective in the removal of COD and various heavy metals present in ABR effluents. The posttreatment in CW resulted in reducing the metal concentrations to 1.95?mg/L, 0?mg/L, and 0.004?mg/L for Ni, Pb, and Cd which were within the permissible water quality standards for industrial effluents. The treatment strategy was effective and sustainable for the treatment of combined industrial wastewater.

Performance evaluation and modeling of a submerged membrane bioreactor treating combined municipal and industrial wastewater using radial basis function artificial neural networks

Mirbagheri, Seyed Ahmad; Bagheri, Majid; Boudaghpour, Siamak; Ehteshami, Majid; Bagheri, Zahra
Fonte: BioMed Central Publicador: BioMed Central
Tipo: text
Publicado em 13/03/2015 Português
Relevância na Pesquisa
46.52%
Treatment process models are efficient tools to assure proper operation and better control of wastewater treatment systems. The current research was an effort to evaluate performance of a submerged membrane bioreactor (SMBR) treating combined municipal and industrial wastewater and to simulate effluent quality parameters of the SMBR using a radial basis function artificial neural network (RBFANN). The results showed that the treatment efficiencies increase and hydraulic retention time (HRT) decreases for combined wastewater compared with municipal and industrial wastewaters. The BOD, COD, documentclass[12pt]{minimal} usepackage{amsmath} usepackage{wasysym} usepackage{amsfonts} usepackage{amssymb} usepackage{amsbsy} usepackage{mathrsfs} usepackage{upgreek} setlength{oddsidemargin}{-69pt} egin{document}$$ {mathrm{NH}}_4^{+}-mathrm{N} $$end{document}NH4+?N and total phosphorous (TP) removal efficiencies for combined wastewater at HRT of 7 hours were 96.9%, 96%, 96.7% and 92%, respectively. As desirable criteria for treating wastewater, the TBOD/TP ratio increased, the BOD and COD concentrations decreased to 700 and 1000 mg/L, respectively and the BOD/COD ratio was about 0.5 for combined wastewater. The training procedures of the RBFANN models were successful for all predicted components. The train and test models showed an almost perfect match between the experimental and predicted values of effluent BOD...