Study On Electric/PRB Remediation Of Chromium And Arsenic Of Soil

With the improvement of the economic level of our country and the development ofindustrial and agricultural, heavy metal pollution of soil accident happen frequently. Thepollutants such as waste water and slag that contain heavy metal will be produced by industrialand agricultural production activities, due to the improper disposal, the pollutants could bedischarged into the soil directly or indirectly, then the pollutants could be discharged into body,that can affect the health of human body. Therefore, it is necessary to deal with the heavy metalpollution of soil and groundwater.Electrokinetic remediation technology is an in situ remediation technology that can dealwith the heavy metal pollution of soil. Electric and PRB combined remediation combineelectrokinetic remediation technology and PRB, it is an economically feasible remediationtechnology. In this paper, by the experimental study, to investigate the feasibility ofelectrokinetic remediation technology, electric and PRB combined remediation technology forremoval of heavy metals in the soil and groundwater, optimization of experimental parameters,for the electric and PRB joint technical field to provide technical support, we can get thefollowing main results:1.The test run for four days, the constant voltage is30V, the ancode and carhode of pHcontrol mode for acetic acid and sodium hydroxide balance control system. The electrokineticremediation technology that use the plate electrode(electric field) can remove Cr(Ⅵ) of thecontaminated kaolin well, the removal rate reach80%. The electrokinetic remediationtechnology that use the rod electrode(non uniform electric field) can not remove Cr(Ⅵ) of thecontaminated kaolin well, the removal rate only reach10%. Electric and PRB remediationtechnology can remove Cr(Ⅵ) of the contaminated kaolin well, the removal rate reach85%,and it need to have low energy consumption.2. The test run for four days, the constant voltage is30V, the ancode and carhode of pHcontrol mode for acetic acid and sodium hydroxide balance control system. Electric remediationtechnology can remove arsenic of the contaminated kaolin well, the removal rate reach60%.Electric and PRB remediation technology can remove arsenic of the contaminated kaolin well, the removal rate reach70%.3.The test run for four days, the constant voltage is30V, the ancode and carhode of pHcontrol mode for acetic acid(citric acid) and sodium hydroxide balance control system.Electrokinetic remediation technology, electric and PRB combined remediation technology canremove Cr(Ⅵ) of the contaminated soil well, the removal rate reach60%. After the test, the pHof soil is still high, in8.5-9.5. Electric and PRB combined remediation technology can notremove Cr(total) of the contaminated soil, the removal rate reach12%.4.The test run that extended to fourteen days, the constant voltage is30V, the configurationof acetic acid and water in the ratio of5:8to the actual pollution in soil, the anode and cathodepH control method as the cathode and the cathode by acetic acid control remain strong acid,anodic cyclic control, enhanced electrokinetic remediation technology can remove Cr(total) ofthe contaminated soil, the removal rate reach40%. After the test, the pH of soil decreased, pHwas below6.5, that improved the pH of alkaline soil.