Cold hydrogenation wet-process dust removal slag slurry discharging system and method

Abstract

The invention discloses a cold hydrogenation wet-process dust removal slag slurry discharging system and method, relating to the field of polysilicon cold hydrogenation dust removal equipment. The system comprises a washing tower and a slag slurry treatment device, and is characterized by also comprising a slag slurry receiving tank, wherein the slag slurry receiving tank is arranged between the washing tower and the slag slurry treatment device; the top end of the slag slurry receiving tank is provided with a slag slurry inlet valve; the slag slurry inlet valve is fixedly connected with the bottom of the washing tower; the top end of the slag slurry receiving tank is also provided with a balance valve and an emptying valve; and the bottom of the slag slurry receiving tank is provided with a slag slurry outlet valve. The bottom of the cold hydrogenation washing tower is provided with the slag slurry receiving tank, and the system pressure is relieved by using the slag slurry receiving tank instead of a disk valve, thereby reducing the system abrasion and lowering the failure rate.

Description

technical field [0001] The invention relates to the field of polysilicon production equipment, and more precisely relates to a cold hydrogenation wet dedusting slurry discharge system and a method thereof. Background technique [0002] At present, the mainstream technical route of polysilicon production is to improve Siemens, in which about 20 kg of silicon tetrachloride is produced by-product for every kilogram of polysilicon produced, and the by-product silicon tetrachloride is mainly transformed by the cold hydrogenation technology of silicon tetrachloride. The conversion process is mainly carried out in a cold hydrogenation reactor, and silicon powder needs to be added to the reactor at the same time as the conversion. As the reaction progresses, the silicon powder becomes smaller and is carried out by the reaction gas. The follow-up system generally uses wet dust removal to wash down the silicon powder, and the formed liquid slurry needs to be discharged from the sy...

AI Technical Summary

Problems solved by technology

However, since the slurry contains a large amount of silicon powder solids, under such a large pressure difference, the flow rate of the valve and the pipeline is very fast, and the ultra-fine silicon powder and chloride crystals in the slurry are likely to cause the sealing of the valve under high-speed flow. Lax or even impossible to close

Once the valve is not tightly sealed or cannot be related, the chlorosilane liquid in the wet dust removal system will be lost in large quantities, resulting in insufficient system liquid, resulting in system shutdown

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