Abstract: Metal vapor, for example zinc fume in the offgas of a smelting furnace, is captured by bringing the stream into direct contact with a fluidized bed of solid particles having a particulate loading of greater than 10 kg/m.sup.3 and preferably greater than 400 kg/m.sup.3. The thermal mass and temperature of the bed is such as to rapidly quench the vapor in the case of zinc from above 960.degree. C. to below 419.degree. C. in less than 100 milliseconds, whereby the vapor condenses in the bed and is recovered as zinc metal in acceptable yield.

Abstract: A method for the treatment of a mixture of lead dusts and pyritic concentrates said method including the steps of:a) feeding a mixture of lead dust and pyritic concentrate to a furnace containing molten slag;b) smelting the mixture by injecting air or oxygen enriched air into the slag by means of a submerged lance to produce a lead bearing slag; andc) recycling fume to the furnace.A method for the treatment of lead dusts, without pyritic concentrate, said method including the steps of:a) feeding lead dust to a furnace containing molten slag;b) smelting the dust by injecting air or oxygen enriched air into the slag by means of a submerged lance to produce a lead bearing slag; andc) recycling fume to the furnace.