Structural optimization of gas-solid separator used in TMSR-SF based on computational fluid dynamics

Abstract

The fission gas removal system plays a critical role in the Thorium Molten Salt Reactor-Solid Fuel (TMSR-SF). A gas–solid separator is used to separate the waste gas and solid particles in the gas removal system. As a key component of the system, the gas–solid separator directly determines the system energy efficiency. Nowadays, a new combined gas–solid separation equipment combining axial flow blade cyclone separator and filter for TMSR-SF have been studied. However, the primary separation efficiency of the new separation equipment is low, resulting in a large number of particles entering the secondary filter and causing wear and tear of the filter material. Based on the above considerations, a new combined gas–solid separator consisting of a stable chamber with swirl louver structure and a filter is developed for the TMSR-SF in this study. The velocity and pressure fields of two phases in this new combined separator are calculated and analyzed by using commercial software FLUENT, and the separation performance for this structure is also discussed. Then the structure is optimized considering the influence on pressure and separation efficiency. The results show that the RNG k-ε is feasible and accurate to simulate the flow fields of the new combined separator. Coarse particles are separated in the first-stage by mechanical separation and fine particles are separated in the second-stage filter. The mechanical separation efficiency of the first stage separator with the optimum structure can reach 72.49%. The unit pressure drop separation efficiency of the new combined separator is increased by 30.32% and much better than the original combined separator.