Iranian Research Organization for Science and Technology Advances in Environmental Technology 2476-6674 6 4 2020 10 01 Hardness and chloride removal in dewatering system: Modeling and optimization of electrochemical reaction 251 265 1050 10.22104/aet.2021.4535.1254 EN Ali Hasanzadeh-Sabloue Department of Mining Engineering, Higher education complex of Zarand, Kerman, Iran Seyed Morteza Moosavirad Department of Environment, Institute of Science and High Technology and Environmental Sciences, Graduate University of Advanced Technology, Kerman, Iran Journal Article 2020 11 26 The electrocoagulation (EC) process is a novel approach in the mining industry, especially to recycle water in the dewatering system of a mineral processing plant. In this research, the electrocoagulation process was studied to remove the hardness and chloride ions from concentrate thickener overflow water under different operating conditions: retention time (5–15 min), initial pH (4–10), current density (41.6–166.6 A/m2) and electrode type (Fe, Fe-Al, Al). Four factors with three levels with the D-optimal response surface design were applied for optimization. As a result, the optimal situation for the electrocoagulation process was characterized by a retention time of 15 min, initial pH of 9.08, the current density of 139.59 A/m2, and electrode type Fe-Al. In this situation, the maximum removal efficiency of hardness (60.11%) and chloride (98.38%) were yielded with a desirability value of 0.989. These results illustrated the effectiveness of the EC process as an influence method for the removal of hardness and chloride in terms of separation. https://aet.irost.ir/article_1050_5055cbf43fac3f7e2336b27310f0b9ef.pdf