Xia, W.-.Y, Y.-J. Du, K.R. Reddy, Y.-S. Feng, W.-W. Ren, and M.-L. Wei.
Journal of Materials in Civil Engineering 30(6):(2018)
Filed Under: Research
Filed Under: Research
KMP, a new and innovative binder composed of acid-activated phosphate rock, monopotassium phosphate, and reactive magnesia, was developed for solidification/stabilization of soils contaminated with heavy metals, such as Pb, Zn, and Cd. An investigation of the strength, leachability, and microstructural properties of KMP-stabilized field clayey soil was conducted for a smelter site contaminated with Pb, Zn, and Cd. With increasing binder content and curing time, the leached Pb, Zn, and Cd concentrations decreased while the unconfined compressive strength and dry density of the stabilized soil increased. Sequential extraction results indicated the transfer of large percentages of Pb, Zn, and Cd from the exchangeable fraction to the residual fraction after KMP stabilization. Analyses demonstrated the formation of magnesium phosphate-based products and heavy metal phosphate-based products in the stabilized soil—the primary mechanisms for strength increase and heavy metal immobilization, respectively. See also a comparison of the performance of KMP binder and Portland cement at http://www.ejge.com/2018/Ppr2018.0046ma.pdf.