Method and device for purifying and recycling emitted argon in preparation process of monocrystalline silicon

Abstract

The invention relates to a method and device for purifying and recycling emitted argon in a preparation process of monocrystalline silicon. The method comprises the following steps of: collecting crude argon emitted by a monocrystalline silicon furnace and then carrying out compression oil removal treatment, removing carbon monoxide and alkane by adopting a catalytic oxidation method, removing oxygen by adopting a hydrogenation oxygen removing method, removing carbon dioxide and water by adopting an adsorption method, and removing nitrogen and hydrogen by adopting a high-low pressure dual-tower low-temperature distillation method to finally obtain pure compressed argon which can be directly conveyed to the monocrystalline silicon furnace for being recycled. The device comprises a crude argon collecting and pretreating system for carrying out crude oil filtration on the crude argon emitted by the monocrystalline silicon furnace, a compression oil removing system for filtering refine oil, a catalytic reaction system for removing carbon monoxide, alkane and oxygen components, a crude argon purifying system for removing the carbon dioxide and the water, a low-temperature distillation system for removing the nitrogen and hydrogen components, an air treating system for providing a raw material air source for a process of preparing the nitrogen by the low-temperature distillation system, and an automatic control system for controlling the whole set of device. The method and device can realize that a large quantity of protection argon in the monocrystalline silicon industry is recovered and recycled.

Description

technical field [0001] The invention relates to a method and a device for discharging argon gas in a process for purifying and recovering single crystal silicon, and belongs to the technical field of purification and recovery of argon gas. Background technique [0002] Argon is an inert gas that is non-toxic, colorless, odorless, incombustible and non-combustible. Due to the chemical inertness of argon, its unique physical properties, and its lower cost compared to other inert gases, argon is widely used in many industries of the national economy as protective gas, carrier gas, and dilution gas, such as electronics, metallurgy, Chemical industry, physical and chemical analysis, light source, welding, single crystal silicon preparation, etc. In the application, its inertness is mainly used, so the purity of argon is required to be as high as possible, and the impurities contained in it are as small as possible, so as not to lose the protective effect due to the reaction of ...

AI Technical Summary

Problems solved by technology

Among them, the first four methods can only remove specific impurities for specific gases. To completely remove impurity gases, a multi-stage joint purification process is required.

Although the metal getter method has the ability to fully absorb impurity gases, but because the getter alloy is made of rare and precious metals, it is expensive and easy to deactivate, so far it can only be applied on a laboratory scale and cannot be used in large-scale industrial applications.

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