化工污染场地氟污染土壤的稳定化技术研究

Research on stabilization technique of fluoride contaminated soil in chemical contaminated sites

通过以某电解铝厂内的氟污染土壤为研究对象,添加钙、镁、铝剂及碱性材料共8种不同材料作为稳定剂开展稳定化修复技术研究,分析不同稳定剂对土壤pH值和氟化物浸出毒性的影响,探讨稳定剂对氟化物的稳定效果。结果表明:钙剂、镁剂、铝剂均降低了土壤pH值和氟化物的浸出浓度,其中氯化铝的投加量为3%时稳定效果最佳,氟化物浸出浓度下降了90.32%。土壤氟化物浸出浓度在pH值于6.5~12.5变化时,以pH=9.5为拐点,在pH=6.5时稳定效果最佳。

Taking fluoride contaminated soil in an electrolytic aluminum plant as the research object,8 different materials including calcium,magnesium,aluminum and alkaline materials were added as the stabilizing agents to develop stabilized remediation technology research,the effects of different stabilizing agents on soil pH value and fluoride leaching toxicity were analyzed,and the stabilization effect of the stabilizing agents on fluoride was discussed.The results show that calcium,magnesium and aluminum all reduce the pH value and the leaching concentration of fluoride in soil,among which 3%aluminum chloride has the best stabilization effect,and the leaching concentration of fluoride decreases by 90.32%.When the leaching concentration of fluoride in soil varies from pH=6.5 to pH=12.5,regarding pH=9.5 as the inflection point,the stability effect is the best at pH=6.5.