Equipment for treating by-products of hydrogenation of silicon tetrachloride

Abstract

The invention provides a device for treating a hydrogenated by-product of silicon tetrachloride, and the device comprises a gas-solid separation device and a heat exchange device, wherein the gas-solid separation device is used for carrying out gas-solid separation on the hydrogenated by-product of the silicon tetrachloride so as to obtain a first gas mixture containing trichlorosilane, silicon tetrachloride, dichlorosilane and hydrogen, and solid particles; the heat exchange device is connected with the gas-solid separation device, and is used for receiving the first gas mixture from the gas-solid separation device and carrying out heat exchange between the first gas mixture and second gas mixture so as to enable the temperature of the second gas mixture to be increased, wherein the second gas mixture is a mixture of silicon tetrachloride and hydrogen. The device for treating the hydrogenated by-product of the silicon tetrachloride is simple in structure, convenient in operation, low in energy consumption and cost and high in heat recovery rate. Furthermore, a pipeline can be prevented from being blocked by the solid particles, so that the utilization rate of a solid material is improved, and the normal operation of the pipeline and equipment can be guaranteed.

Description

technical field [0001] The invention relates to the field of polysilicon production, and more particularly, to equipment for treating by-products of hydrogenation of silicon tetrachloride. Background technique [0002] In the polysilicon production process, a large amount of by-product silicon tetrachloride is produced. For example, when polysilicon is produced using the hydrogen reduction process of trichlorosilane (improved Siemens process), 10-20 tons of silicon tetrachloride will be produced for every ton of polysilicon produced. Silicon tetrachloride is a toxic chemical substance, which is easily hydrolyzed to generate silicic acid and hydrogen chloride, which seriously pollutes the environment. Therefore, how to safely handle silicon tetrachloride has become a hot research topic at present. At present, the most effective way to deal with silicon tetrachloride is to convert silicon tetrachloride into trichlorosilane, the raw material for polysilicon production, under ...

AI Technical Summary

Problems solved by technology

Silicon tetrachloride is a toxic chemical substance, which is easily hydrolyzed to produce silicic acid and hydrogen chloride, which seriously pollutes the environment

[0003] However, because the by-products containing silicon tetrachloride contain a small amount of solid particles such as silicon powder and catalyst, it is easy to block equipment and pipelines, and its heat cannot be recovered, resulting in high energy consumption, high cost, and unstable operation

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