The Study Of Tailings And Solidified Tailings Heavy Metal Leaching Toxicity And Speciation Analysis Of Heavy Metals

In this paper,the heavy metal leaching toxicity test was conducted on tailings,the leaching amount of heavy metals in tails with different particle sizes,p H values and Eh was measured.The stability was analyzed by speciation analysis of heavy metals in tails.The compressive strength test,the heavy metal leaching toxicity test and the speciation analysis was also conducted on solidified body which was solidified by slag cementitious material.The results show that:1.There is no physical sealing effect when particle size ranges from 0.075 mm to2.0mm,the leaching amount of heavy metals increases with the decrease of p H and with the increase of Eh.The results of Tessier method speciation analysis indicated that the heavy metals in tails have a poor stability.2.The results of the compressive strength test indicated that there is an optimal mix proportion between slag,desulfurized fly ash,limestone and activator with 77:17:4.5:1.5.The compressive strength of specimens after curing are higher than the minimum that the solidified body landfill demands,and it increases with the increase of curing ti me and concentration of slurry.3.The leaching concentrations of Pb,Cr,Cu are all lower than the Solid waste leaching toxicity identification standard value through the leaching test of solidified body and they decrease with the increase of curing time.it was found that there is physical sealing effect in solidified body through the leaching toxicity test with different particl e sizes,p H and Eh.The leaching amount of heavy metals increases with lower p H or higher Eh.The result of speciation analysis showed that the stability of heavy metals i ncrease and the mobility of heavy metals decrease after solidification.