Study on the application of high gravity technology in the rapid cooling process of radioactive high temperature flue gas

The cooling of the high-temperature flue gas produced by incineration currently needs to be achieved through the use of multiple cooling methods and their combinations, resulting in complex cooling processes and equipment. Meanwhile, one-step cooling of flue gas with high-temperature is difficult to achieve, and there is an urgent need to develop new technologies. The study on the application of high gravity technology in the rapid cooling of radioactive flue gas with high-temperature has been proposed in this paper. A micro-element mathematical model for direct contact of gas–liquid and heat and mass transfer within a typical type of high gravity device-the cross-flow rotating packed bed has been innovatively established, and the influence of equipment parameters (radius and height of packing ring) and process parameters (high gravity factor, gas phase temperature, gas and liquid flow rates) on the rapid cooling effect of flue gas were analyzed. Optimized operation parameters were obtained for specific working conditions, and a high gravity experimental device, with verification by using simulated radioactive flue gas, was built based on the simulation results. Results showed that the temperature of flue gas with a flow rate of 600 m3/h was rapidly lowered from 600 to 800°C to below 150°C by the high gravity technology in just one step. The temperature deviation between the experimental results and the simulation predictions was less than 20%, verifying the accuracy of the model. The feasibility of the high gravity technology as a compact and efficient solution for handling radioactive waste gas with high-temperature has been confirmed.