水泥固化铅污染粘土的pH-Dependent试验研究

通过pH-dependent试验,研究水泥固化铅污染土的溶出特性.对滤出液pH的研究结果表明,滤出液pH随加酸量增加而下降,且试样C12Pb2较C12Pb0、试样C18Pb2较C18Pb0的碱性/酸缓冲能力弱.对滤出液中铅浓度（Pb]）随滤出液pH、水泥掺量的变化特征进行分析,结果表明,Pb]随滤出液pH增大而先减小后增加;且试样C18Pb2较C12Pb2,其溶出的Pb]显著减小,铅最大溶出率小5个百分点,表明水泥掺量的增大使得水泥对铅的固定效果更好,使固化土中可溶出的铅减少.

Research into pH-Dependent Tests of Cement Solidified Lead Contaminated Clays

This paper investigates the leaching characteristics of cement solidified/stabilized Pb-contaminated kaolin via pH-dependent leaching tests. The results of the eluate pH show that the pH of eluate decreases with the increase of acid. And the alkalinity/acid buffer capacity of C12Pb2 is weaker than that of C12Pb0; the alkalinity/acid buffer capacity of C18Pb2 is weaker than that of C18Pb0. The change of lead concentration in eluate （ Pb] ） with pH of eluate and cement content is analyzed. The results reveal that the Pb] rises before decreasing as pH of eluate increases. Compared with C12Pb2, the Pb] of C18Pb2 is significantly lower and the maximum leaching rate of lead is lower by 5%, indicating that the increase of cement content produces strong solidification effects on the lead and reduces the amount of leachable lead in solidified soil.