Technical method for treating silicon carbide acidic wastewater

Abstract

The invention belongs to the technical field of environment protection, and relates to a technical method for treating acidic wastewater generated during the production of silicon carbide. The technical method is characterized by comprising the technical steps of pretreatment and descending of high-concentration suspended matters, neutralization, flocculation and precipitation, sand filtration and primary advanced treatment, and ultrafiltration and secondary advanced treatment; water after ultrafiltration treatment with a UF is 6-9 in pH value, less than 10 mg / L in SS, and less than 10 mg / L in COD; the water is delivered to a clean circulation water tank to substitute new water and use as reuse water; water production rate is above 95%; concentrated water during the ultrafiltration is returned to an acidic wastewater adjusting tank. According to the invention, waste water with high-concentration suspended matters, of which the SS is more than 20000 mg / L can be treated; silicon carbide resource can be recycled directly; silicon carbide purity is guaranteed; reuse water with high quality is produced; construction investment and capital for upgrading are reduced; running cost is reduced; reuse of reclaimed water and sediment as resource is guaranteed; the sediment can be used as construction materials, decorative materials, environment-friendly materials and agricultural fertilizer improving soil.

Description

technical field [0001] The invention belongs to the technical field of environmental protection, and relates to a method for purifying and treating industrial acidic wastewater, in particular to a process for treating acidic wastewater produced in the silicon carbide production process. Background technique [0002] Silicon carbide is a typical polymorphic compound, which can be divided into α-silicon carbide and β-silicon carbide. Silicon carbide has a wide range of uses, and plays an irreplaceable role in many fields of metallurgy, machinery, electronics, and chemical new energy as purifiers, deoxidizers, hard alloys, ceramic micropowders, electronic components, and coating materials for national defense spacecraft. It is widely used in international and domestic economic fields. The production process of silicon carbide micropowder is to take silicon carbide raw materials, crush, sieve, shape to (2-5) mm particles, then pickle them to remove impurities, dry them, and fin...

AI Technical Summary

Problems solved by technology

[0003] The present invention overcomes the above-mentioned defects, and aims to provide a process for treating acidic wastewater generated in the silicon carbide production process in order to solve the problems of environmental protection, water saving, resource recycling and the like in the silicon carbide production process

Images