Arsenite removal mechanism from groundwater in a two-dimensional batch electrochemical treatment process

This research work presents treatment of arsenite contaminated groundwater using batch electrochemical coagulation process using iron electrodes. The influence of various operating conditions was studied for applied cell voltages 6, 8, 12, and 16 V and specific surface area/volume ratio 40, 60, and 100 m(2)/m(3) for electrolysis time (ET) of 60 min with constant initial As(III)(0) of 3 mg/L. The focus was to decrease arsenic concentration to the prescribed drinking water quality standards, to exercise water quality control of other parameters after electrochemical treatment (ECT), to optimize anode dissolution, to control sludge volume, to lower the energy consumption and to minimize operating cost. The operating conditions were pre-set with an intent to retain the water mineral content after ECT. For the optimal operating conditions of 16 V 4 electrodes (4E - 4 no. of Fe electrodes) arrangement, As(III) was reduced from 3 to 0 mg/L in a shortest ET of 10-15 min with electrode dissolution 0.7838 kg/m(3), dry sludge 1.21 kg/m(3), energy consumption 0.397 KWh/m(3) with a corresponding operating cost of INR 1.15/m(3), such a low cost was because the operating conditions were established in this work. Thus, ECT proved as an effective and efficient treatment technology for arsenic (III) removal from groundwater.