Crystal silicon wafer cutting edge flotation carbon removal method

Abstract

The invention discloses a wafer cutting edge material floatation and decarburization method, and aims to solve the technical problems that an existing wafer cutting edge material decarburization method is not thorough in decarburization and low in decarburization efficiency, and after treatment, obtained silicon carbide micro powder is low in purity, and cannot be used directly. The method comprises the following steps: mixing materials, adding a flotation agent and heating slurry; continuously introducing compressed air to a floatation pond and stirring; removing a carbon powder impurity layer produced by air flotation on the liquid level by a scraping plate; and pumping the slurry into a siphon cylinder, forcedly stirring, hydraulically settling and classifying, then pumping into an inclined tube treating device and a scraper blade centrifugal machine, and respectively carrying out concentrating treatment and centrifugal dehydrating and separating treatment; drying obtained silicon carbide micropowder, and then using the silicon carbide micropowder after the silicon carbide micropowder is sieved by a high-frequency vibration feeder. The method is high in operability, thorough in decarburization and high in efficiency; and the obtained silicon carbide micropowder is high in purity and good in granularity concentration, can be directly used as a wafer cutting edge material, and is high in popularization and application value.

Description

technical field [0001] The invention relates to the technical field of flotation of crystalline silicon wafer cutting edge material, in particular to a method for removing carbon by flotation of crystalline silicon wafer cutting edge material. Background technique [0002] The cutting edge of crystalline silicon wafer is a finer silicon carbide solid micropowder particle with a particle size usually between 5 μm and 15 μm. It is hard and has sharp edges and corners. It is used as a cutting edge for cutting solar crystalline silicon wafer cells. Polysilicon cut into pieces. Crystalline silicon wafer cutting blades are often mixed with impurity carbon powder during the preparation process, and certain measures need to be taken to remove it, and finally obtain silicon carbide micropowder within the specified particle size range. At present, carbon removal often adopts the method of cyclone separation or overflow carbon removal, and additives are added to adjust the pH value, a...

AI Technical Summary

Problems solved by technology

The above method has the problems of incomplete carbon removal and low carbon removal efficiency, and the treated silicon carbide micropowder has low purity and poor particle size concentration, which cannot be used directly, and it is difficult to meet the needs of crystal silicon wafer cutting blades