METHOD FOR PROCESSING ARSENIC-CONTAINING DUST OF NON-FERROUS METALLURGY Russian patent published in 2022 - IPC A62D3/32 C22B7/02 B09B3/00 C01G28/02 

FIELD: non-ferrous metallurgy.

SUBSTANCE: invention relates to the field of metallurgy of non-ferrous metals. The proposed method can be used in pyrometallurgy for the processing of arsenic-containing dust with the transfer of arsenic into a sulfide-metal melt based on iron. The cooled iron-arsenic matte is suitable for burial in the open ground without the use of special burial grounds for highly toxic substances, which include arsenic oxides. When processing arsenic-containing non-ferrous metallurgy dusts with subsequent disposal of arsenic in the form of the obtained arsenopyrite or iron arsenide, a charge containing iron sulfide compounds, a carbon-containing reducing agent and a silicate flux is fed into the electric furnace. The mixture is melted with the formation of slag and matte melts, the latter are separated by settling. A periodic separate output of liquid products of melting and gases is carried out. Arsenic-containing dust is fed into the melt through a pipe buried in the slag melt of the electric furnace using pneumatic transport. The surface of the melt in the electric furnace is covered with a layer of charge. The temperature of the iron-silicate slag is 1220±30°C, the temperature of the sulfide-metal melt is 1200±10°C. The ratios of Fe, As and S in the starting materials are such that they provide matte with a bulk composition related to the systems FeS-FeAs₂-FeAsS, FeS-Fe₃As₂-FeAs.

EFFECT: eduction of the level of environmental pollution with toxic arsenic-containing compounds is ensured when arsenic-containing raw materials of non-ferrous metals are involved in the processing.

1 cl, 7 dwg