Method for processing slags of non-ferrous metallurgy

摘要

A method for processing slags containing iron and non-ferrous metals, to produce clean slag free of detrimental substances and non-ferrous metals and suitable for use as a raw material or construction material. Slag is reduced in a reduction furnace with the help of reducing agents so that at least 5% of the iron of the slag is reduced into metal. Some of the non-ferrous metals, such as zinc, lead, arsenic and cadmium, vaporize. The contents of the reduction furnace are continuously mixed to prevent separation of a metallic phase from the slag. The generated slag-metal mixture is tapped off from the reduction furnace, cooled, crushed and ground to a finer size. Finally, a metal fraction is separated from a clean slag.

主权项

1. A method for processing slag containing iron and non-ferrous metals, the method comprising the steps of:
feeding the slag into a reduction furnace; reducing the slag in the reduction furnace by means of a reducing agent to convert at least some of the non-ferrous metals to metallic form, where reduction occurs at least until 5 mass-% of the iron has reduced into metal and at least some of the non-ferrous metals has vaporized; mixing the contents of the reduction furnace during reduction to prevent settling of metal droplets from the slag; tapping a molten slag-metal mixture generated in the reduction furnace; cooling, crushing and grinding the slag-metal mixture; processing the slag-metal mixture to separate a metal fraction from a remaining clean slag, where the remaining clean slag is suitable as raw material in a useful process.