Quality analysis/quality control tests for field stabilization/solidification—2. Untreated waste, sodium silicate solution and solidified waste

This paper reports on the efficacy of selected quality analysis/quality control testing procedures that were used during a full-scale stabilization/solidification trial of an arc furnace dust with high multiple contaminants. The quality analysis/quality control test results of untreated waste, sodium silicate solution and solidified waste are discussed. Moisture content of the untreated waste was measured to control water addition. It was found that sodium silicate concentration in solution was linearly related to its specific gravity. Thus, hydrometer measurement of specific gravity was used to control the silicate concentration in solution. Bulk density, moisture content, and cone and K-slump of freshly solidified wastes were measured. Laboratory measurement of bulk density and moisture content of freshly solidified wastes correlated well with water addition. It appeared from the field data that bulk density measurement underestimated the actual water-to-solid ratios, while moisture content measurement overestimated them. Cone slump and K-slump measurements fluctuated widely, the measurements were within the range normally observed from different types of concrete.