Casting technique for aluminium or aluminium alloy

The invention relates to a technique of aluminum or aluminum casting, which is used for solving the problem of aluminum slag comprising a smelting of aluminum raw material. The invention is characterized in that during the smelting process the slag remover and the refining agent are added, the smelted hot aluminum slag is transferred via a sealed and heat preserved transferring chamber to a hopper, then the hot aluminum slag is poured into a high temperature boiler by a lifter via tilted feeding opening and continuously churned, the aluminum liquid flows out from the bottom of the high temperature boiler and returns to a smelting boiler, the solid aluminum slag enters a chilling roller to be cooled, the chilled solid slag is graded via winnowing, crude and fine slag are obtained, return the crude slag to the smelting, and use the fine slag as the raw material for electrolyte. Selectively addition of slag remover the refine agent, enabling the recycle of aluminum slag and ash produced in the recycling process to completely return and recycle. The invention improves the recycle rate of aluminum and avoids environmental pollution of the aluminum ash.