Cupola furnace fitted with dust extn. plant - in which dust is returned to the cupola via an air injection pipe

摘要

Foundry plant using at least one cupola furnace having tuyeres supplying the hot blast, has equipment for the dry extn. of dust form the cupola throat gas. The equipment includes a cyclone dust catcher and a screw feeder driving the dust to a venturi nozzle so all or part of the dust can be injected into or below the molten zone in the cupola. The cyclone is pref. located between the cupolar throat and a combustion chamber, and collects dust >100 mu dia., while a bag filter plant collecting dust 100 mu dia. is located downstream of the combustion chamber. The venturi nozzle is pref. supplied with cold or hot injection gas, possibly obtd. form the hot blast supply pipe. The dust extn. plant prevents environmental pollution, and the dust is fed back to the cupolar for redn. of the SiO2 in the dust to add Si to the molten iron.