MATHEMATICAL MODEL AND NUMERICAL SIMULATION OF THE PLASMA PROCESSING OF RADIOACTIVE WASTE

The technology of plasma processing of radioactive waste as a promising method for addressing environmental issues related to its disposal is examined. The fundamental principles of plasma technology are presented, utilizing high-temperature plasma for the treatment of radioactive waste. The process is described, in which organic compounds decompose into gaseous components, while inorganic substances transform into a vitrified slag. The advantages of the method are analyzed, including a significant reduction in waste volume (up to 90%), environmental safety, and the potential for energy utilization. The main drawbacks of the technology, such as technological complexity and high energy consumption, are considered. A mathematical model of the physicochemical processes in a plasma reactor is presented, based on the Navier-Stokes equations and the Maxwell equation system. The mechanisms of radioactive compound decomposition and the kinetics of the processes in the plasma reactor are described. The results of numerical modeling are provided, demonstrating the efficiency of the plasma processing process. Optimal operating parameters of the system and their impact on process productivity are presented. The energy characteristics and mass balance of the process are analyzed. It is shown that the technology ensures a high degree of gas emission purification (99.95%) and low residual activity of the slag (<10⁻⁶ Ci/kg). The influence of temperature on the decomposition rate of radioactive waste and ionization efficiency is studied. A schematic of the plasma installation is presented, along with a description of its main components. The processes of heat and mass transfer in the reactor are analyzed. It is demonstrated that the implementation of this technology will contribute to solving the problem of radioactive waste disposal and improving the environmental situation.