A method for recycling waste sand of foundry green mold sand

Abstract

The invention discloses a regenerating method of waste sand of casting green sand. The regenerating method comprises the following steps: previously doping brown fused alumina abrasive into waste sand, feeding into a calcinator, boiling and calcinating, cooling and screening after the calcination to separate the brown fused alumina abrasive, namely the regenerated crude sand for casting. According to the method disclosed by the invention, since the brown fused alumina abrasive and the waste sand of casting green sand are previously mixed and fed into the calcinator for calcinating, the waste sand and the brown fused alumina abrasive are in friction in the calcinating process; the adhered bentonite on the surface of the waste sand can be effectively and completely removed since the brown fused alumina abrasive has corner angle, high strength and can resist the temperature at 1500 DEG C, and the aim of reducing acid consumption value of the crude sand for casting for regenerating is achieved. And meanwhile, the invention further discloses the crude sand for casting, the crude sand is obtained by regenerating by adopting the method; the acid consumption value is effectively reduced, and the regenerated crude sand is free from a plurality of times of grinding, and the strength of the crude sand cannot be damaged.

Description

technical field [0001] The invention relates to a method for recycling waste sand, in particular to a method for regenerating waste sand for casting green mold sand. Background technique [0002] If the green mold sand waste sand is only regenerated through normal roasting, the residual bentonite bonded to the original sand is not easy to dispose of, resulting in a high acid consumption value of the final regenerated sand, which cannot be used for the production of foundry self-setting sand and coated sand. [0003] In the prior art, in order to reduce the acid consumption value of the regenerated sand, the regenerated raw sand is generally ground for many times. Although this can reduce the acid consumption value to a certain extent, it will destroy the strength of the original sand itself and increase the original sand. The mud content of the sand will reduce the yield and increase the operating cost. Contents of the invention [0004] The purpose of the present inventi...

AI Technical Summary

Problems solved by technology

[0002] If green mold sand waste sand is only regenerated through normal roasting, the residual bentonite bonded to the original sand is not easy to dispose of, resulting in a high acid consumption value for the final regenerated sand, which cannot be used for the production of foundry self-setting sand and coated sand.

[0003] In the prior art, in order to reduce the acid consumption value of the regenerated sand, the regenerated raw sand is generally ground several times. Although this can reduce the acid consumption value to a certain extent, it will destroy the strength of the original sand itself and increase the The mud content of the sand reduces the yield and increases the operating cost