Removal Of Heavy Metals In Sandy Soil By Electrokinetic Remediation

Soil remediation of heavy metals is one of the key research directions in the field of soil pollution control.The traditional repairing technology has a large quantity and easy to produce secondary pollution.This study adopts the technology of the electrokinetic remediation technology to remove contaminated sandy soil Zn,Cr,Cu,Ni,Pb,Cd six heavy metal pollutants,selecting soil area of Taixing by a chemical plant solid waste pollution as experimental sites,the site soil heavy metal within the range of 50-150cm as the experimental object.During the experiment,the electrode current,electrolyte parameters(pH,conductivity,redox potential and temperature)and the content of six heavy metals in soil before and after remediation were analyzed.The results show that electrokinetic remediation technology has very good removal effect on six kinds of heavy metals in sandy soil,heavy metals in the soil within the depth of 50-100cm removal rate were Zn(57.7%),Cr(60.5%),Cu(67.2%),Ni(42.7%),Pb(32.2%),Cd(75%);in the range of 100-150cm heavy metal removal rate were Zn(94.3%),Cr(71.9%),Cu(82.9%),Ni(35.6%),Pb(81.1%),Cd(68.4%).Electrode current gradually increased with time to repair,until smooth.Two months of the equipment energy consumption was 8164.74 kW-h,electricity cost of 6531.79 yuan.The electrolyte pH value and temperature in the normal range,the overall redox potential is positive.Different electrode electrolyte conductivity increased with the repair time,the cathode electrolyte conductivity increases first and then stabilizes,the anode remained stable.This study provides a reference for the application of electrokinetic remediation of heavy metal contaminated soil.The technology has good repair efficiency,short time and small amount of engineering,which has very broad application prospects.