Co-stabilization of Waste Containing Heavy Metals

The following report concerns neutralization of electroplating sludges (ES) from one of Polish galvanizing plants, characterized by very high concentrations of Cr, Zn and Ni. The technology of stabilization/solidification (S/S) was applied to sludges containing heavy metals. Mixtures based on Portland cement and mixtures of fly ashes (FA) from pit-coal combustion were used. Stabilization/solidification processes are distinguished by low costs, as well as they create possibilities for utilization of produced monoliths. Compression strength of products obtained, possibilities of replacing Portland cement with fly ashes, as well as the effect of drying neutralized sludge on mechanical parameters of obtained products of solidification were assesed in described research. In order to estimate effectivity of immobilization of Cr, Zn and Ni leaching tests were performed according to the TCLP procedure (standard for the United States) and the procedure described in PN-EN 124574:2006, being in effect in the European Union. Based on the results obtained, the level of contaminants immobilization (PRC) was calculated.