Electrocoagulation (EC) — science and applications

Mollah, M. Yousuf A.; Schennach, Robert; Parga, José R.; Cocke, David L.

doi:10.1016/s0304-3894(01)00176-5

Cited by 1,209 publications

(715 citation statements)

References 23 publications

Supporting

Mentioning

583

Contrasting

Unclassified

Order By: Relevance

“…When the effluent also contains chloride ions, Cl 2 will be formed at the anode and could react with water to generate hypochlorite ions. This fact can be considered to be a great advantage for EF, because chlorine generation can be optimized for both the disinfection of the water and the elimination of undesirable odors (Mollah et al, 2001).…”

Section: Mechanismmentioning

confidence: 99%

See 1 more Smart Citation

Electroflocculation for textile wastewater treatment

Cerqueira

Russo

Marques

2009

Braz. J. Chem. Eng.

View full text Add to dashboard Cite

-This work reports on the viability of the electroflocculation (EF) process for chemical oxygen demand (COD), turbidity and color removal from a raw effluent originated from a particular textile industry related to hemp manufacture. Firstly, the following operational parameters were optimized: current density; initial pH; electrolysis time; material of the electrode (iron, aluminum or iron-aluminum); and interelectrode distance. Additionally, the effects of these parameters on specific electrical energy consumption (SEEC) were studied under the optimum conditions. The best removal efficiencies obtained were 93% for color, 99% for turbidity and up to 87% for COD using an aluminum electrode, the initial pH was 5, the cell time operation was 30 min and current density was 15 A/m 2 . These results indicate that, under the studied operational conditions, electroflocculation of these efluents may constitute a viable alternative for COD, turbidity and color removal.

show abstract

Section: Mechanismmentioning

confidence: 99%

“…Two mechanisms have been proposed for the production of Fe(OH) n (Mollah et al, 2001;Xu and Zhu, 2004).…”

Section: Introductionmentioning

confidence: 99%

Electroflocculation for textile wastewater treatment

Cerqueira

Russo

Marques

2009

Braz. J. Chem. Eng.

View full text Add to dashboard Cite

show abstract

“…Electrocoagulation (EC) is gaining recognition as an alternative process to conventional chemical coagulation (CC) of EC include a compact treatment facility, relatively low cost, less sludge production, minimum requirement of chemicals, and the possibility of complete automation [1][2][3][4]. During the last few decades, EC technology has undergone a rapid development, and has been proved to be competitive and effective in the treatment of drinking water and wastewater to remove heavy metals [5][6][7], anions [8,9], organic compounds [10][11][12][13], oil [14,15], and particulates [16,17].…”

Section: Introductionmentioning

confidence: 99%

“…Dissolved anode produces various Al or Fe hydrolysis species, which involve charge neutralization and sweep flocculation of particles or adsorption of pollutants onto Al or Fe hydroxides [1,12]. Many researchers have demonstrated that Al species distribution during CC and EC process determined the performance of both Al based coagulants [18][19][20][21] and EC with Al electrode [22].…”

Section: Introductionmentioning

confidence: 99%

An effective method for improving electrocoagulation process: Optimization of Al 13 polymer formation

Wang

Sun

et al. 2016

Colloids and Surfaces A: Physicochemical and Engineering Aspect

View full text Add to dashboard Cite

h i g h l i g h t s• Al 13 polymer formation in EC process are investigated.• Al 13 species fraction positively correlated with removal of turbidity and organic.• pH 5-7 and lowering j favored the formation of Al 13 polymer.• Al 13 fraction can reach more than 60% under optimal EC conditions. Keywords: Electrocoagulation Aluminum species Electrochemical parameter a b s t r a c t Al 13 polymer has been believed to be the most active species responsible for coagulation. The character of Al species distribution and the formation of Al 13 polymer in electrocoagulation (EC) process were investigated in order to provide insight into optimizing EC operation and design. The results indicated that predominant Al species shifted from monomer toward medium polymer then to larger polymer or Al(OH) (s) with increasing EC time. The in-situ Al 13 polymer could be generated in EC process, and became the dominant species during 5-15 min. In EC process, Al 13 species fraction positively correlated with the removal of turbidity and organic. The increase of pH and current density could accelerate the hydrolysis-polymerization process of Al 3+ . pH 5-7 and lowering current density favored the formation of Al 13 polymer during EC process, EC process with bipolar electrodes had a higher yield of monomeric and Al 13 species, while EC process with monopolar electrodes facilitated the formation of larger polymer or Al(OH) (s) . The content of Al 13 polymer can reach more than 60% under optimal conditions.

show abstract

“…As unidades de EF são pequenas e compactas, além de requererem pouca manutenção e custos operacionais menores quando comparados a outras unidades de flotação. 8,9 Além disso, a EF tem despertado bastante interesse, devido à sua simplicidade de operação e aplicação para o tratamento de diversos tipos de efluentes, dentre os quais se destacam: a indústria de processamento de coco, 9 de esgotos sanitários, 10 de restaurantes, 11 de siderurgias, 12 de indústrias têxteis, 13,14 de curtumes, 15 , além de facilitar a remoção de íon fluoreto, 16 de boro 17 e de óleos. [18][19][20][21][22][23] Tipos de reações envolvidas no processo de EF Quando se utiliza o eletrodo de alumínio, ocorre a sua oxidação no anodo (1), o qual, após solvatação, sofre hidrólise (2) com a formação do agente de floculação -Al(OH 3 ).…”

unclassified

Avaliação do processo eletrolítico em corrente alternada no tratamento de água de produção

Cerqueira

Marques

2011

Quím. Nova

View full text Add to dashboard Cite

objective was to study the treatment of wastewater generated by the oil industry. This work consisted of tests of electroflocculation with alternate current (AC), and chemical coagulation. The removal efficiencies of organic load were evaluated by the removal of oils and greases, color and turbidity. The parameters investigated were the change in alternate current frequency, the initial pH, the distance between electrodes, the applied potential and time lapse. From the results, one may conclude that the electroflocculation process is potential applicability to the effluent studied, while chemical coagulation was not successful.Keywords: electroflocculation; offshore platforms; water production. INTRODUÇÃOAs atividades de exploração de petróleo, devido à crescente preocupação com o meio ambiente e ao surgimento de novas leis e resoluções ambientais mais restritivas, precisam se enquadrar dentro das novas exigências. Uma das questões mais preocupantes envolve a água de produção gerada nessa atividade, a qual aumenta gradativamente em volume à medida que os poços vão envelhecendo e que novos poços são perfurados. 1 Normalmente, essa água corresponde a mais de 90% de todos os efluentes gerados na indústria do petróleo: em média, para cada m³/dia de petróleo produzido são gerados de 3 a 4 m³/dia de água, podendo chegar a 7 ou mais, nas atividades de exploração, perfuração e produção. Para que a água produzida possa ser descartada em corpos receptores ou utilizada na reinjeção em poços de petróleo, é necessário o seu tratamento prévio para enquadrá-la na legislação vigente. A Resolução CONAMA 357/2005, 4 estabelece que para o descarte em corpos receptores, o limite de óleos e graxas na água produzida é de até 20 mg/dm 3 . Especificamente, para descarte em plataformas off-shore, aplica-se a Resolução CONAMA 393/2007, 5 que estabelece a média aritmética simples mensal do teor de óleos e graxas de até 29 mg/dm 3 , com valor máximo diário de 42 mg/dm 3 . Para reinjeção em poços de petróleo, a água deverá ter no máximo 5 mg/dm 3 de óleos e graxas.Uma parte do óleo presente na água de produção está na forma de emulsão devido às partículas sólidas finamente divididas oriundas da perfuração, assim como os produtos químicos residuais utilizados na desestabilização de emulsões óleo/água (O/A) e as moléculas surfactantes naturais do petróleo. 6 Neste caso, o diâmetro das gotas situa-se abaixo de 50 μm, o que dificulta a sua separação por meios gravitacionais. A separação do óleo emulsificado requer a desestabilização da emulsão O/A, a qual é governada por quatro diferentes fenômenos: coagulação, floculação, sedimentação (creaming) e coalescência. 7 O creaming é o deslocamento gravitacional das gotas para a superfí-cie da fase contínua em função da diferença de densidade entre as duas fases, não necessariamente após a coagulação e/ou floculação das gotas.A colisão entre as gotas pode levar à coalescência com a formação de grandes agregados até se tornar novamente uma fase contínua separada do meio dispersante por uma simples inte...

show abstract

Electrocoagulation (EC) — science and applications

Cited by 1,209 publications

References 23 publications

Electroflocculation for textile wastewater treatment

Electroflocculation for textile wastewater treatment

An effective method for improving electrocoagulation process: Optimization of Al 13 polymer formation

Avaliação do processo eletrolítico em corrente alternada no tratamento de água de produção

Contact Info

Product

Resources

About