Utilization of Dry Calcium Based Flue Gas Desulfurization Waste as a Hazardous Waste Fixation Agent

Several designated hazardous wastes (metal plating waste, oil sludge, heavy metal processing sludge) were studied relative to potential detoxification using dry calcium based FGD sludges. The FGD waste was generated from a pilot scale system which utilized slurried lime, a spray drier, and a bag filter. Following detailed physical and chemical identification of the raw FGD and hazardous wastes, various mixtures were prepared and cured. In all cases, even with the organic sludge, a rigid structural material evolved due to the pozzolanic reactions occurring from the wetted dry FGD waste. Structural characteristics, physical character, and chemical leaching effects were evaluated. The solids were leached via both EPA-RCRA and ASTM proposed leaching procedures. In all cases, the hazardous constituents were retained and not leached. Finally, the feasibility of using dry FGD wastes as fixating materials is discussed.