Removal of Hardness from Groundwater by Electro-coagulation Using Aluminium Electrode

There are many problems associated with industrial and domestic use of hard water. The need to develop of modern and cost effective technologies to remove water hardness is highly demand due to the growing demands for water of high quality both for industrial and domestic uses. Various techniques with their own advantages and disadvantages can be used for removal of water hardness. One of the techniques is the electro-coagulation process (EC). This study is carried out to investigate the efficiency of EC process in hardness removal from brackish groundwater using aluminium electrodes. This EC process is conducted in batch reactor and under different current density and distance between electrodes. Moderately hard groundwater from tube well 2 of intial hardness 118.34mg/L could be reduced to 52.17mg/L within one hour by using current density of 20V/20mm2 and electrode spacing of 2cm. The production rate was 200mL/hour. The removal of hardness by using batch volume of 200mL is greater than 5000mL. The removal efficiency of batch of 200mL is 72.18% while the batch of 5000mL is 17.25%. The concentration of two major contribution cation which are calcium and magnesium have been decreased to 200 mg/L and 150 mg/L respectively. Hardness in groundwater can be reduced by electrocoagulation process. The production rate was 200mL/hour. This rate of production is considered appropriate only for drinking water supply.