GTS Duratek (GTSD) recently performed two laboratory-scale steam reforming demonstrations of processing selected non-radioactive samples for Japanese clients, Ishikawajima-Harima Heavy Industries Co., Ltd. (IHI) and Nuclear Fuel Industries, Ltd. (NFI). Sample materials included PVC pipe, silicone rubber tubing, animal carcasses (chicken wings), PVC and acrylic plates, rubber gloves, and HEPA filters. The primary objective of these studies was to determine if the steam reforming process is capable of destroying the subject materials with an acceptable level of volume reduction, and to develop the data necessary to prepare full scale operation and system costs. Tests performed included Thermal-Gravimetric Analysis (TGA), Steam Reformer Apparatus (SRA), and Rotary Thermal Apparatus (RTA) tests on the materials supplied by IHI, NFI, and GTSD. Prior to performing steam reforming on the surrogate wastes, weight loss versus temperature data was acquired using an apparatus designed to perform TGA testing. The resulting PVC pipe TGA residue was either a black carbonaceous material with areas of dusty, fine whitish-yellow powder that was about 13.5% of the original sample weight, or a very dusty, fine whitish-yellow powder that was about 9% of the original sample weight. The silicone rubber tubing TGA test produced a fine white powder and very friable white tubing pieces that were about 35.4% of the starting weight. The chicken wing TGA test provided a black char that was about 17.8% of the starting weight. There was almost no detectable residue remaining after the PVC/acrylic plate TGA test, making it impossible to calculate the weight reduction. The rubber glove TGA data exhibited a sharp decomposition curve and produced almost no residue. The HEPA filter TGA test provided a final residue that was about 36% of the starting weight, with the wood reduced to char and evidence remaining of some of the initial materials (foil and glass fiber). The systems used to perform the bench-scale steam reforming tests were the Steam Reformer Apparatus (SRA) or the Rotary Thermal Apparatus (RTA), both consisting of an evaporator, reformer, offgas condensate collector, offgas non-condensable gas sample collection hardware, and ancillary equipment. The SRA and RTA testing indicated that the mass and volume reductions were generally comparable within any particular test, with the mass and volume reduction on PVC, acrylic, and rubber gloves between 85% and 95%. The mass and volume reduction on HEPA Filter parts (approximately 80%) was somewhat less than for tests composed of plastics. The mass and volume reduction on chicken wing parts (approximately 95%) was somewhat better than for tests composed of plastics. The residue from the silicone rubber tubing test was very powdery with relatively low weight and volume reduction (between 45% and 65%). Volatile/semi-volatile priority pollutants and anion analyses were performed on typical condensates by a commercial laboratory using gas chromatograph/mass spectroscopy in accordance with EPA methods. These analyses indicated that the organic and anion content (except for the PVC condensate chloride level), was sufficiently low for the condensate to be recycled as make-up water to the steam boiler. Selected solid residues were analyzed for total metals, ultimate analysis, and for crystal structure (by x-ray diffraction). Based on the results, all of the organic wastes are suitable candidates for steam reforming. This is particularly true if they are pre-shredded to increase the surface area and diffusion rate; processed in a Heated Screw Evaporator or blended for processing in a Drum Feed Evaporator; and the final residues are lightly compacted. Compaction will consolidate the friable plastic and bone residues, break up the wood char from the HEPA filters, and provide volume reduction for the non-organic materials, such as the HEPA filter glass fiber media and aluminum foil. The effects of the very light silicone
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