Pollution Level And Electrokinetic Remediation Of Chromium In Agricultural Soil Around Chromate Plant

Chromate plant residue field storage may pollute the soil. Based on theenvironmental standard and environmental quality risk assessment criteria for soil ofChina, the investigation on the pollution level and assessment of chromium in agriculturalsoil samples around chromate plant and the research on technology of electric repairchromium contaminated soil can be of great significance for prevention and remediationof soil pollution. The176agricultural soil samples were collected according to radialdistribution method near chromium slag disposal site and a radius of150m in11areas at10cm interval from the surface layer to the underground150cm vertically on eachmonitoring point. The results showed that the concentration of Cr(VI) and total chromiumdecreased with the increase of the chromium slag disposal site distance. The content ofCr(VI) in the soil near pile of chromium slag was significantly higher than the backgroundvalue and the surface soil Cr(VI) content is up to30.54mg/kg that the pollution index was5.7. The content of Cr(VI) decrease with increase of the soil depth. The total chromiumpollution index in surface soil near Chromium slag heap is highest for4.61. The Cr(VI)content in soil is less than the standard value proposed by Environmental quality riskassessment criteria for soil at manufacturing facilities. Using experimental devicedesigned electric repair soil of chromium polluted。The performance of electric repair soilrestoration of polluted by chromium is investigated in the lab by using the self-designedexperimental device. The results showed that the chromium removal efficiency increasedwith the increase of the applied voltage and treatment time. Controlling pH value of thecathode by acetic acid can improve the repair efficiency of chromium contaminated soilremoval efficiency up to83.77%from67.39%. Each soil section removal rates varygreatly. Within the5to35m scope of the anode, a total chromium removal rates atdifferent voltages increase with the increase of distance from the anode, which areshowing a linear positive correlation tendency between total chromium removal rate ofchromium-polluted soil and the distance from the anode. Produced at the cathode ofOH-has great influence on the removal efficiency of Cr, used in the acid solution and canbe an effective way to improve the removal efficiency.