Electrochemical advanced oxidation and biological processes for wastewater treatment: A review of the combined approaches

Environmental Science and Pollution Research (Impact Factor: 2.76). 07/2014; 21:8493-8524. DOI: 10.1007/s11356-014-2770-6

ABSTRACT As pollution becomes one of the biggest environmental challenges of the XXI century, pollution of water threatens the very existence of humanity, making immediate action a priority. The most persistent and hazardous pollutants come from industrial and agricultural activities, therefore effective treatment of this wastewater prior to discharge into the natural environment is the solution. Advanced oxidation processes (AOPs) have caused increased interest due to their ability to degrade hazardous substances in contrast to other methods, which mainly only transfer pollution from wastewater to sludge, a membrane filter or an adsorbent. Among a great variety of different AOPs, a group of electrochemical advanced oxidation processes (EAOPs); including electro-Fenton, is emerging as environmentally friendly and effective treatment process for the destruction of persistent hazardous contaminants. The only concern which slows down a large-scale implementation is energy consumption and related investment and operational costs. A combination of EAOPs with biological treatment is an interesting solution. In such a synergetic way, removal efficiency is maximized, while minimizing operational costs. The goal of this review is to present cutting-edge research for treatment of three common and problematic pollutants and effluents: dyes and textile wastewater; olive processing wastewater; pharmaceuticals and hospital wastewater. Each of these types is regarded in terms of recent scientific research on individual electrochemical, individual biological and a combined synergetic treatment.

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Available from: Eric D Van Hullebusch, Jul 25, 2014
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