Investigation For Reducing Exhaust Recovery In Chlorosilane Production

With the consumption of a large number of traditional oil and coal,renewable energy is growing and expanding because of its variety.Solar power generation is not only absolutely clean and abundant,but also simple maintenance,safe operation and low cost,so it is especially important in renewable energy.Compared with foreign countries,polysilicon enterprises in China have a prominent problem of waste pollution,thus restricting the development of domestic polysilicon enterprises and becoming a bottleneck problem in the polysilicon industry.Polycrystalline silicon is the basic material of the photovoltaic industry,its demand with the rapid development of photovoltaic industry continues to increase.The purification of trichlorosilane is the key step to improve the production of polysilicon by Siemens.The purity of trichlorosilane directly affects the quality of polysilicon products.The principle of dichIorosilane redistribution and the type of catalyst were studied in this paper.By setting up a small test device,it was verified that using a fixed bed redistribution reaction under the action of a specific catalyst A21 can maximize the conversion of dichIorosilane,and the influence of different reaction conditions on disambiguation is obtained.At the same time,a small test device was set up to screen the chlorosilane adsorbents,and the optimum control temperature of different adsorbents was explored.The best chlorosilane purification catalyst and operating conditions were obtained,which provided guidance for the industrial production.At the end of the paper,the results of the small test were used to analyze the problems of the existing plants.Adsorption distillation technology and dihalogen dihydrogen disilane disproportionation technology were added to existing plants.By monitoring field measurement data,comparative analysis of test data was found.The recovery of SiH₂Cl₂ reached 95.4%.The quality of the SiCl₃ has been significantly improved after reformation of the rectification production line,and the steam consumption has been reduced by 3197 kg·h^-1,the reduction of steam single consumption of polysilicon by 13.97%,and the residual volume of chlorosilane silicon has been reduced by 88 kg·h^-1.eduction of chlorosilane residues by 9.77%Therefore,compared with the original system,the reformed distillation system can effectively reduce the energy consumption and the waste amount of the system.