PRODUCING ALUMINUM-SILICON ALLOYS FROM HIGH-ALUMINUM BEARING COAL FLY ASH BY CARBOTHERMAL REDUCTION METHOD

摘要

In this paper, the feasibility of producing aluminum-silicon alloys by carbothermal reduction of high-aluminum bearing coal fly ash is studied. The mixing ratio for a furnace charge was 60～80 % coal fly ash; 20～40% bitumenite and petroleum coke as reducing agent. The mixing ratio of bitumenite and petroleum coke was in the range of 8:2～6:4; with 5～8% calcium lignosulphonate as binder. All these raw materials were mixed uniformly in the given proportions, briquetted and dried, then the carbothermal reduction experiments were conducted in a 1.25MVA mineral thermal furnace with temperature 1900～2100°C and time 4h. The aluminum-silicon alloys containing 50～55% aluminum and 40～45% silicon were obtained with recovery rates for aluminum in the range of 80～85% and for silicon in the range of 75～80%.