Chromium removal from drinking water by redox-assisted coagulation: Chemical versus electrocoagulation

Abstract

Chemical Coagulation (CC) and Electrocoagulation (EC) processes using iron as coagulating agent were compared while treating aquifer water contaminated by a relatively high concentration of total chromium (CrT =19.0 mg L-1). A continuous semipilot comprising of EC (or CC), followed by flocculation, sedimentation and sandfiltration steps was used to remove CrT from water in order to get drinking water. A ratio of Fe/CrT ≥ 3 was required to reach the best efficiency of treatment using EC and CC. More than 99% of CrT was removed and residual CrT concentration below 0.05 mg L-1 (the limiting value recommended by WHO) could be obtained using the both configurations. However, CC increased the concentration of dissolved solids above the guideline recommended for drinking water.

Electrocoagulation as a green technology for phosphate removal from river water

“…It has been well documented that EC technology is able to remove as much as 95-99% of various pollutants within a relatively short treatment time (Gao et al, 2010;Ricordel et al, 2014;Hashim et al, 2017b;Nariyan et al, 2018). It has been successfully used to purify water of pathogens (Ricordel et al, 2014), strontium (Nur et al, 2017), heavy metals (Hashim et al, 2017c;Martín-Domínguez et al, 2018), phosphate (Behbahani et al, 2011;Attour et al, 2014), and organic matter (Vepsäläinen et al, 2012).…”

Nitrogen-Containing Fabric Adsorbents Prepared by Radiation Grafting for Removal of Chromium from Wastewater

“…The maximum permissible limit for chromium content in drinking water recommended by the World Health Organization (WHO) is 0.05 ppm. Chemical precipitation [2], electrochemical reduction and coagulation [3], membrane separation [4], ion exchange [5,6] and adsorption [7,8] are used for removing chromium from wastewater. Among these methods, adsorption is effective for the chromium removal [9].…”

Electrocoagulation Based Chromium Removal Efficiency Classification Using Logistic Regression

“…Chromium is a heavy metal that must be treated and removed in wastewater, and there are several articles that treat this metal in different ways and different treatment methods. For example, this article [18] made a comparison between coagulation and electrocoagulation using iron to treat the water contained in the aquifer contaminated by a relatively high concentration of total chromium. The results showed that more than 99% of (Cr) was eliminated by the Coagulation and Electrocoagulation methods.…”