重庆某铅污染场地稳定化修复技术研究

以重庆市某铅污染场地为研究对象,选用多种稳定化药剂对土壤开展稳定化修复技术研究,着重探讨了不同单一药剂与复配药剂对土壤铅浸出浓度的影响。实验结果表明:磷酸二氢钠(MSP)、磷酸氢二钠、磷酸钠和石灰4种无机药剂中MSP的稳定化修复效果最佳,且磷酸盐类的稳定化修复效果整体上优于石灰;MSP与少量有机药剂腐殖酸复配施用的稳定化修复效果优于单独施加MSP;在MSP投加比(与土壤的质量比)为5%、腐殖酸投加比为2%、养护时间为7 d的最优工艺条件下,土壤中铅的浸出浓度由41.70 mg/L降至0.16 mg/L,低于《生活垃圾填埋场污染控制标准》(GB 16889—2008)中规定的0.25 mg/L浓度限值。

Study on stabilization remediation technology for a lead-contaminated site in Chongqing

Taking a lead contaminated site in Chongqing as the research object,the stabilization remediation technology of soil was studied by using a variety of stabilizing agents,and the effects of different single agents and compound agents on the leaching concentration of lead from soil were discussed in detail. The experimental results show that：Among the 4 inorganic chemicals of monosodium phosphate （MSP）,disodium hydrogen phosphate,sodium phosphate and lime,MSP has the best stabilization remediation effect,and the stabilization remediation effect of phosphate is better than that of lime as a whole;The stabilization remediation effect of MSP combined with a small amount of organic humic acid is better than that of MSP alone;Under the optimal process conditions of MSP dosing ratio （mass ratio to soil）5%,humic acid dosing ratio 2% and curing time 7 d,the leaching concentration of lead from soil is reduced from 41.70 mg/L to 0.16 mg/L,which is lower than the 0.25 mg/L concentration limit specified in the MSW Landfill Pollution Control Standard （GB 16889-2008）.