Study of effect of immobilization materials on heavy metal stabilization treatment in sediment

Key words: 
• sediment /
• heavy metal /
• stabilization /
• leaching toxicity

Abstract: Several chemical immobilization materials, CaO, NH4H2PO4 (MAP), Ca(H2PO4)2 (MCP), (NH4)2HPO4 (DAP), NaH2PO4 (MSP) and M1 reagent, were evaluated by leaching toxicity experiments to determine their effects on heavy metal stabilization in contaminated sediment. The results show that after the treatment of 75 g/kg CaO, the concentrations of Zn, Pb, Ba and Mn eluted were reduced 72.8%, 67.6%, 34.9% and 94%, respectively. After the treatment of 200 g/kg M1, the concentrations of Zn, Ba and Mn eluted decreased 85.1%, 76.1% and 99%, respectively, meanwhile reducing Pb eluted with a more than 95%. When the addition amounts of MAP, MCP, DAP, MSP were 100 g/kg, 70%～85% of Zn eluted,40%～90% of Mn eluted decreased and more than 95 % of Ba eluted declined. In addition, total phosphorus eluted by the treatment of MAP, MCP, DAP, MSP increased markedly.