INSTALLATION AND PROCEDURE FOR TREATMENT OF SOLUTIONS FOR ETCHING STRIPS OF SILICON STEEL Russian patent published in 2011 - IPC C23G1/36 C23G3/02 

FIELD: metallurgy.

SUBSTANCE: procedure consists in continuous etching said strips passing at least through one etching tank with etching solution on base of hydrochloric, sulphuric or nitric acids with addition or without addition of fluoro-hydrogen acid and in treatment of silica produced in said etching solution in form of colloid suspension and in dissolved form. Treatment of silica consists in transfer of etching solution from the etching tank into a preparing reservoir whereto there is added a filtration additive facilitating formation of filtration sediment and production of filtration mixture, in transfer of solution designed for filtration into a filtration section for production of filtration sediment with high content of silica and etching solution with low content of silica. For continuous filtration there are used two filter sections arranged parallel. One of them is in operation state, while another is successively in stages of purification, recovery of operational condition of filtration and waiting till another section completes working stage of filtration.

EFFECT: reduced expenditures, simplified process.

16 cl, 5 dwg