Electric Arc Furnace dust, blended with a suitable reductant and flux is fed into a reactor vessel where a plasma torch producing melt temperatures as high as 1500 deg C causes the reduction of the metal compounds. Zinc, lead and cadmium are reduced and volatilized and a non-hazardous inert slag is produced. The exhaust gases consisting of carbon monoxide, carbon dioxide, and metal vapours pass through a splash condenser for the recovery of up to 85 percent of the metallics. From the condenser, the gases pass into a refractory lined afterburner where they are oxidized with excess air. Immediately following the afterburner, ambient air is introduced to cool the gases sufficiently to be transported in mild steel ducting where further radiant/convective cooling takes place. Finally additional tempering air is added just prior to a baghouse to cool the gases to 135 deg C to protect the fabric. Oxides are then collected in the baghouse and recycled to the process.
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