Recent Applications of Electrocoagulation in Treatment of Water and Wastewater—A Review

Abstract

<span>During the last two decades, and particularly during the last few years, the environmental sector has shown a largely growing interest in the treatment of different types of water and wastewater by electrocoagulation (EC). The aim of this work was to review studies, conducted mainly during 2008</span><span>-</span><span>2011, on the wide and versatile range of feasible EC applications employed in the purification of different types of water and wastewater. The EC applications discussed here were divided into 7 following categories: tannery, textile and colored wastewater; pulp and paper industry wastewater; oily wastewater; food industry wastewater; other types of industrial wastewater; surface water as well as model water and wastewater containing heavy metals, nutrients, cyanide and other elements and ions. In addition, this paper presents an overview of the optimum process conditions (treatment times, current densities, and initial pH) and removal efficiencies (mostly high) achieved for the EC applications discussed. In the vast majority of the studies discussed in this review, the aforementioned values were found to be in the range of 5</span><span>-</span><span>60 min (typically less than 30 min), 10</span><span>-</span><span>150 A</span><span>/m² and near neutral pH, respectively. Both operating costs and electrical energy consumption values were found to vary greatly depending on the type of solution being treated, being between 0.004</span><span> -</span><span>6.74 €/m³ and 0.002</span><span>-</span><span>58.0 kWh/m³, but in general they were rather low (typically around 0.1</span><span>-</span><span>1.0 €/m³ and 0.4</span><span>-</span><span>4.0 kWh/m³).</span><span></span> <p> <span></span> </p

Application of Electro-Coagulation for Treatment of Wastewater From Package Printing Process

“…1). Two similar aluminum plate electrodes with effective area of 84 cm 2 were placed vertically in the cell and connected to a DC power supply. Samples with volume of 15 mL were taken from electrocoagulation cell at certain operating times for true color and COD analyses.…”

“…Practically, various methods have been used to treat this wastewater, including chemical coagulation, adsorption, oxidation, biological treatment, and electrolysis [1]. Among these methods, electrocoagulation (EC) has been proposed as an effective method for treatment various types of wastewater from textile, paper mill, baker's yeast, restaurant, and chemical mechanical polishing [2,3]. However, there is very rare report on the application of this technique for printing ink wastewater [4].…”

A Review of Electrocoagulation Process for Wastewater Treatment

“…Gas bubbles H 2 and O 2 adhere to agglomerates which are released at the electrode surfaces during electrolysis and carry them to the water surface [11].…”

Integrated treatment of molasses distillery wastewater using microfiltration (MF)

“…Comparison of various coagulants for color and COD reduction of anaerobically digested molasses spentwash showed that ferrous sulfate and alum (26 g/L each) and poly aluminum chloride (PAC) (8 g/L) resulted in 60e70% color reduction and 30e50% COD reduction (Chauhan and Dikshit, 2012); however, ferrous salts impart color to the treated wastewater. In recent years, there has been renewed interest in use of electrocoagulation (EC) for wastewater treatment (Kuokkanen et al, 2013). This is driven by the benefits of EC in terms of improved economics (low investment, operation and maintenance costs), lower volume of better settling sludge, compact systems that can be readily automated, larger functional pH range etc.…”