Process for separating and recovering cutting waste powder material of solar silicon wafer

Abstract

The invention provides a process for separating and recovering a cutting waste powder material of a solar silicon wafer. The process is characterized by comprising a rotational flow washer, a stirringmaterial barrel, a pump, a solid liquid separator I, a solid liquid separator II, a drier I and a drier II. The cutting waste powder material of the solar silicon wafer is fully dispersed by a washing medium in the stirring material barrel to prepare an even suspension, the main ingredients of the even suspension are silicon and silicon carbide, the suspension is tangentially pumped into the rotational flow washer through a pump and is subjected to multi-level countercurrent washing, a silicon suspension is discharged from an overflow pipe of the primary-level rotational flow washer, a silicon carbide suspension is discharged from an underflow pipe of the tail-level rotational flow washer, the suspension is subjected to solid liquid separation and is dried to obtain a silicon powder and asilicon carbide powder. The process separates and extracts the cutting waste powder material of the wafer to recycle the resource, the continuous high-precision separation of the silicon and the silicon carbide is realized, the cutting waste material is prevented from be discharged to cause environment pollution, the process has the advantages of low water consumption, environment protection, high product purity and the like, and the production cost and the labor intensity are reduced.

Description

technical field [0001] The invention relates to the technical field of solar energy materials and separation and recovery, in particular to a process for separation and recovery of solar silicon chip cutting waste powder. Background technique [0002] In recent years, with the increasing shortage of global oil, coal and other energy sources, solar energy has gradually become the most important new energy source in this century. The global solar energy industry has entered a period of rapid development, and my country has become the world's largest producer of solar cells. To make solar cells, high-purity silicon is cast into polycrystalline silicon ingots, which are then sliced ​​into wafers. Silicon wafer (including monocrystalline silicon and polycrystalline silicon) cutting is one of the key steps in the manufacture of solar cells. It is used to process solid silicon ingots of monocrystalline silicon or crystalline silicon. Its processing efficiency and processing quality...

AI Technical Summary

Problems solved by technology

[0003] At present, there are two main ways to recycle the mixture of silicon carbide and silicon powder in the cutting waste mortar at home and abroad. One is to use chemical methods to remove the silicon powder to recover silicon carbide, because the chemical properties of silicon carbide are more stable, but this results in silicon powder. a lot of waste

The second is to use a series of physical separation methods. The main performance is that the device process is too long, the equipment is bulky, the structural design is unreasonable, and the operating environment has potential risks, resulting in low purity of the separated silicon powder and silicon carbide powder.

However, the cyclone washing system does not design a process for recovering silicon powder, and only recovers silicon carbide, resulting in waste of silicon powder

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