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Show • Which contain medium to high contaminant concentrations (5000 ppm and above). The incinerator is being developed in two steps. In the first step, the operating data from its individual stages are being analyzed to establish the capability of each stage separately. Then, an integrated unit will be designed, constructed, and operated to obtain the performance data and control characteristics of the integrated unit. This paper highlights the data already obtained from the fluidized-bed agglomerating pilot unit as well as from the cyclonic combustor/incinerator pilot unit. DATA AND RESULTS TO DATE Extensive data have been obtained in two key components of the multipurpose incinerator while operating separately. Results of First-Stage Fluidized-Bed Incinerator The fluidized-bed reactor has demonstrated its wide application with gasification and agglomeration of various coals, reclamation of foundry sands, and for destruction of organic contaminants present in spent blast grits. Agglomeration and Encapsulation of Trace Metals IGT's fluidized-bed gasification and incineration system for non-hazardous and hazardous wastes based on its slopedgrid, fluidized bed (SGFB) concept is in the advanced stage of development. A key feature of the process is its ability to agglomerate the ash, entrapping a majority of the trace metals. These agglomerated ash particles produced from a variety of coals (Figure 4) have been tested and have been found to comply with EPA toxicity standards for leachability. Over a 10-year period, IGT has processed many fossil fuels, oil shales, and biomass, and generated several designs based on the SGFB ash agglomerating concept.[6,7] Over 10,000 hours of data has been accumulated with this device. The experience associated with entrapment of trace metals from coals in glassy, essentially non-leachable ash agglomerates can be readily extended to the treatment of contaminated soils and sediments. Another important aspect of these agglomerates is that despite the abundant presence of organic compounds in coals, these agglomerates were completely devoid of any of the organics. Incineration and Reclamation of Spent Foundry Sands A growing need for spent foundry sand reclamation is spurred by the Resource Conservation and Recovery Act (RCRA) sand classification regulations. When a foundry's used sand is classified as a hazardous waste, the dumping costs increase dramatically. This reclassification is occurring with increasing frequency, and some foundries are setting schedules to terminate dumping. -8- INSTITUTE o F GAS TEe H N 0 LOG Y |