REMOVAL OF PHOSPHORUS FROM DOMESTIC SEWAGE BY IRON-CARBON MICRO-ELECTROLYSIS UNDER DYNAMIC AND CONTINUOUS CONDITIONS

摘要

In order to treat eutrophic wastewater, especially waste water containing phosphorus, a process of Fe-C micro-electrolysis was proposed. Based on the principle of iron-carbon micro-electrolysis reaction, OH radical and iron ion which were generated during the micro-electrolysis progress could help to precipitate phosphorus in waste water. This experiment was conducted under dynamic and continuous conditions, in which inflow pH, phosphorus concentration in inflow, hydraulic retention time, contact time, and the volume ratio of iron to carbon were studied with orthogonal design by analyzing the removal ratio of phosphorus during the reaction. The order of the five influence factors was pH, contact time, volume ratio of iron to carbon, influent concentration, and hydraulic retention time in turn. The removal ratio was optimal at pH value of 4.0, influent concentration of 4.0 mg/L, reaction time of 20 min, and the volume ratio Fe to C of 2:1. Under above conditions, the concentration of phosphorus decreases from 4.0 to 0.48 mg/L.