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Experimental tests are conducted to measure the apparent viscosity, the pressure drop, and the heat transfer coefficient of the pipe flow of the Nitrate to Ammonia and Ceramic (NAC) process product slurry. The tests indicate that the NAC product slurry exhibits a typicai pseudoplastic fluid behavior. The pressure drop in the pipe flow is a function of the Reynolds number and the slurry temperature. The results also indicate that at a low slurry temperature, the slurry is uniformly heated peripherally. At a high slurry temperature, however, the slurry may be thermally stratified. In a straight pipe, the Nusselt number is reduced as the slurry temperature increases. I L INTRODUCIIONAs r e g u l a t i o n of t h e w a s t e decontamination process becomes increasingly restrictive, one of the major challenges worldwide is the safe storage of liquid nuclear waste. Over the past 50 years, millions of tons of low-level radioactive waste (LLW) with the cement to make concrete blocks, the NAC process eliminates the nitrate from the LLW by converting it to ammonia gas. Aluminum particles are used as a reductant to complete this conversion. The final product of the NAC process is gibbsite, which can be further sintered to a ceramic waste form. Preliminary tests have indicated that the NAC process not only produces environmentally acceptable waste, but can also reduce the volume of the final waste by up to 70%, as compared with the cement-based grout. This volume reduction represents a significant reduction in cost for final land disposal. The NAC process is an exothermic process, which generates large amounts of heat during the chemical reaction. In order to maintain a desired operating temperature of between 50 and 85°C inside the NAC reactor, a cooling system is required. By considering the initial cost and convenience of operation and maintenance, an external heat exchanger has been selected for cooling the prototype NAC process facility? To design a cooling system and the heat exchanger, one needs to know the flow and thermal behaviors of the product slurry. Unfortunately, this information is not available in the open literature.In order to maintain the properties of the slurry at a constant level, nonradioactive slurry, similar to the final product of -the NAC, is used to simulate the actual slurry. Preliminary tests indicate that the NAC product slurry exhibits a typical pseudoplastic fluid (one type of non-Newtonian fluid) behavior. Because non-Newtonian fluids have more complicated relations between the shear stresses and the velocity field, additional factors must be considered in examining various fluid mechanics and heat transfer phenomena? Knowledge of nowNewtonian fluid mechanics and heat transfer is still in an early stage, and at present, some information can be obtained only by experimental study.Thus, the objective of this study is to experimentally determine these fluid flow and thermal behaviors. IL THETESTFACILITYA test facility has been designed and constructed for measurement of the rheologi...