English.
The effect of electro-kinetic treatment on the removal of main heavy metals in sediment under various voltage drops was investigated. The sediment used in the study was sampled from electroplate factory. The sediment was polluted seriously by heavy metals. In this study three different voltages（20, 25 and 30 V）were applied, the experiments were operated 5d. The results showed that the treatments with different voltage drops had little influence on electroosmotie flow, but electric current were obviously increased. After the treatments, the pH values of sediment were lower than those of untreated sediment. The elimination effects of Zn, Cu, Ni near the anode were better, and the elimination rate were above 80%, 10% and 60% , respectively. Besides, the heavy metals were enriched near the cathode, the enrichment degrees of Zn,Cu,Ni were above 24% ,10% and 33% ,respectively. The enrichment of heavy metals influenced the electrokinetic removal efficiencies. According to the removal efficiencies and electric energy consumption,the suitable voltage of the treatment was 25 V. After the electrokinetic treatment of 25 V voltage drop was applied, the elimination rates of Zn, Cu, Ni near the anode were 94%,74% and 87% , while the total removal effieiencies were only 23% ,4% and 17%, respectively. It was found that all forms of heavy metals were removed partly, and among which the decrease of weak acid fractions were most significant.