Furnace dust recovery process

Abstract

A process for selective vaporization of oxides from recovered waste dust collected from a bag house. Pellets are formed from the waste dust and dried to permit charging in an oxidizing chamber wherein an oxidizing atmospheric is maintained. The chamber is heated to a temperature sufficient to vaporize lead oxide and, if present, also oxides of cadmium, potassium and sodium. The vapors are cooled and separated from furnace gas. The residual oxidized mass is cooled after removal from the oxidizing chamber and fed into a reduction chamber wherein a reducing atmosphere is maintained. The reduction chamber is heated to a temperature of between 1800 and 2000 degrees Fahrenheit to reduce zinc oxide and form zinc vapors which are cooled and separated from furnace gas. Lead oxide particles recovered from the oxidizing process are reduced to lead.

Dependencies are inferred from the claim text.