Simplified industrial method for recovering silicon carbide from mortar generated in cutting process of silicon wafers

Abstract

The invention relates to a simplified industrial method for recovering silicon carbide from mortar generated in cutting process of silicon wafers. The method comprises the steps of: 1. adding diluent in the cutting mortar for reducing system viscosity; 2. carrying out primary separation on the mortar subjected to viscosity reduction by using a precise filter A, and setting and controlling filtering precision according to the requirement of silicon material wire-electrode cutting on the particle size distribution of a silicon carbide abrasive to obtain a solid component S1; 3. carrying out alkali wash, acid wash and rinse on the solid component S1, drying a wet material to directly obtain high-quality silicon carbide which meets the requirement of the silicon material wire-electrode cutting; 4. carrying out secondary separation on the mortar fluid subjected to the primary separation by using a precise filter B, and controlling the filtering precision to ensure that smallest passing particles which can be retained are below 2mu m so as to obtain a solid substance S2, and then separating clear liquid; and 5. carrying out alkali wash, acid wash and rinse on the solid component S2 obtained after secondary separation, drying a wet material to collect and obtain silicon carbide micropowder which has smaller particle size and can be used in other industrial occasions.

Description

technical field [0001] The invention relates to a simple industrial method for recovering silicon carbide from silicon wafer cutting mortar. The application field is mainly the resource utilization of silicon wafer cutting and processing mortar in the solar energy industry and silicon wafer cutting and processing mortar in the electronics industry. The silicon carbide products recovered from the mortar can be reused for wire cutting processing of silicon materials, and can also be used in other places where commercial silicon carbide is applicable. technical background [0002] Silicon wafers are an important foundation for the development of the solar industry. In the process of silicon wafer processing, cutting silicon rods (ingots) into sheets of a certain thickness by special wire cutting equipment is the current international processing method. With the rapid development of the global solar energy industry, the processing volume and demand of silicon wafers have incre...

AI Technical Summary

Problems solved by technology

The on-line separation of fine particles from the higher viscosity mortar system is mostly based on physical separation technology. The removal efficiency of fine particles is low, especially the tiny particles attached to and wrapped on the surface are almost impossible to remove, which also leads to these untreated particles. The fine particle impurities that are completely removed will continue to increase with the cutting process, and will continue to be enriched in the mortar system, cutting quality and efficiency will gradually decline, and eventually lead to the inability to produce qualified silicon wafers