Environmentally Safe Microwave Heating of Non-Polar Materials

Abstract

The current research presents results for the theoretical basis of heat transfer and experimental studies of a microwave method of heating uranium hexafluoride for safe evaporation from containers, including defective, and low- and medium-temperature heating of oil fractions. The process is environmentally safe because heat generation occurs in the bulk of the heated medium and is easily controlled. The proposed method is based on uranium hexafluoride evaporation at the expense of heat energy transferred from substances absorbing microwave energy. The conducted investigation on a laboratory bench with a direct heating regime of samples by microwave field of a travelling wave of lowest mode H10 and in the process studied, samples were heated both individually and in combination with UF6. The results show that it was determined that uranium oxides are the most preferable for use as heat absorbing agents for the microwave heating process. A demonstration on a pilot scale was designed for testing the feasibility of this process. The dielectric characteristics of two components mixing were studied. The penetration depth of microwave into the mixture and heat-absorbing agent amount for process implementation has been determined. Several experimental tests on the environmentally safe technology at pilot scale installation were conducted at various continuous modes. The results revealed from the pilot unit showed that the microwave method of evacuation of DUF6 from steel containers allows them to be emptied safely with practically cold (T<1000C) walls, with high efficiency of using microwave energy (η≈97%) while maintaining the level of pressure in the containers.