Exploration on the Thermal Treatment Technology of Organic and Heavy Metal Co-contaminated Soil
In order to solve the problems of complex disposal process and high disposal cost of organic and heavy metal co-contaminated soil,the effects of heating temperature as well as heating time on the treatment of organic matter and heavy metal compound polluted soil were investigated,the best thermal treatment parameters were determined.The experimental results show that with the increase of heating temperature,the contents of polycyclic aromatic hydrocarbons,polychlorinated biphenyls and petroleum hydrocarbons gradually decrease,the leaching concentrations of cadmium,copper,nickel,lead,arsenic and mercury first increase and then decrease,and the proportion of weak acid extracted content gradually decrease.When heated at 400℃,the leaching concentration of heavy metals and arsenic increase gradually with the decreasing of heating time.It is found that after heating,the content of soil clay decrease,the content of coarse sand increase,the content of soil organic matter and the pH value of soil decrease,while the total amount of soil water-soluble salt increase significantly.It is concluded that the best thermal treatment parameters are heated at 400℃for 4 hours,the leaching concentrations of heavy metals and arsenic meet the class IV quality standard of groundwater,and the content of organic pollutants meet the requirements of class I construction land.
万方数据
维普
