Resource utilization method of polycrystalline silicon byproduct silicon tetrachloride

Abstract

The invention relates to a resource utilization method of polycrystalline silicon byproduct silicon tetrachloride. The method comprises the following steps: silicon tetrachloride liquid in a silicon tetrachloride storage tank is added into the inlet of a Venturi tube inlet cylinder section with a mechanical pump; a mixed solution of deionized water and a dispersing agent is introduced from a Venturi tube cylinder throat part, such that silicon tetrachloride is subjected to a reaction with deionized water in the Venturi tube; a mixture discharged from the opening of a Venturi tube conical diffusion section is refluxed into the silicon tetrachloride storage tank, and is subjected to a cyclic reaction; when all the mixed solution of deionized water and the dispersing agent is added, aging is carried out; and filtering, washing, drying and collection are carried out. The method provided by the invention is safe and controllable, and also has the advantages of mild reaction conditions. Product performances can be controlled through controlling the parameters such as the ratio of silicon tetraoxide flow rate to deionized water flow rate, dispersing agent dose, spray drying temperature, and the like, such that silicon dioxide products with different aggregate particle sizes and specific surface areas can be obtained. With the method, healthy and fast development of the polycrystalline silicon industry is promoted, environment pollution is reduced, energy is saved, and emission is reduced.

Description

technical field [0001] The invention relates to a resource utilization method of polysilicon by-product silicon tetrachloride. Background technique [0002] In recent years, with the development of the polysilicon industry, the problem of the disposal of its by-product silicon tetrachloride has become increasingly prominent. According to statistics, about 10-15 tons of silicon tetrachloride are produced by-product of every ton of polysilicon produced. Silicon tetrachloride is a highly corrosive, toxic and harmful liquid, which is extremely harmful to safety and environmental protection. How to effectively solve the problem of silicon tetrachloride, a by-product of the polysilicon industry, is crucial to the development and implementation of the photovoltaic industry. Sustainable development strategy is of great significance. [0003] At present, there are two main ways to deal with silicon tetrachloride, a by-product of polysilicon: one is to make silicon tetrachloride, a ...

AI Technical Summary

Problems solved by technology

Although the above-mentioned patents can all prepare precipitated silica, they all have shortcomings such as excessive reaction, difficulty in controlling, large particle size of the prepared silica, and poor activity. How to make the reaction mild, small in particle size and high in activity has always been an Difficulties in preparing precipitated silica

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