Electrocoagulation (EC) technology for nitrate removal

High nitrate contamination in drinking water is a serious environmental pollutant, as it is generally a problem associated with anthropogenic activities. Sources of nitrate pollution include discharge of chemical fertilizers, human and animal wastes. Excessive application of agricultural fertilizers has been known to cause penetration of large quantities of nitrates into underground and surface waters. Nitrate is a stable and highly soluble ion with low potential for precipitation or adsorption. These properties make it difficult to remove using conventional water treatment method. Several methods have been proposed in the literature for the removal of nitrate. In this project, a laboratory batch electrocoagulation (EC) reactor was designed to investigate the effects of the different parameters, such as: electrolysis time, current value, and the pH of the solution on the nitrate removal efficiency. The influence of process parameters on denitrification was achieved using “synthetic” water. The results showed that at an operating current of 2.5A, the nitrate removal efficiency was 90% when initial nitrate concentration and electrolysis time respectively were kept at 45 mg/L -N and 90 min. The denitrification process is more efficient for pH ranging from 9 to 11. Further it is shown that a linear relationship exists between the electrolysis time for total nitrate removal and the initial nitrate concentration. It is concluded that the electrocoagulation technology for denitrification can be an effective process provided that the ammonia byproduct can be removed effectively.