Covering slag of square billet continuous casting crystallizer and production method thereof

The invention discloses a covering slag of a square billet continuous casting crystallizer and a production method of the covering slag, wherein cheap electrolytic aluminium waste residual material is effectively added to a formula for the covering slag of the square billet continuous casting crystallizer for use; fluorine, carbon, sodium, aluminium and other chemical elements contained in the electrolytic aluminium waste residual material can substitute or partially substitute one or multiple out of materials of chemical elements used in the formula for the covering slag of the square billet continuous casting crystallizer; and the quality performance of the products can achieve and meet the enterprise standard. The invention provides a new method for reasonably using the electrolytic aluminium waste residual, and the new method can effectively reduce bulk deposition of the electrolytic aluminium waste residual and the problem of pollution and has good environmental protection benefit and social benefit. More importantly, with the application of the electrolytic aluminium waste residual in production of the covering slag of the square billet continuous casting crystallizer, expensive fluorine, carbon, sodium, alluminium and other materials are effectively complemented with low cost, thereby greatly reducing cost for producing the covering slag of the square billet continuous casting crystallizer, and having remarkable effect.