PURPOSE: To recover high-purity Zn from the material contg. by-product Zn of an iron works by reducing and volatilizing the material in a volatilization furnace kept at a specified temp. and filled with a reducing atmosphere, bringing the obtained ZnO or Zn into contact with sulfuric acid, and neutralizing the formed ZnSO4 with Na2CO3 to obtain ZnCO3.
CONSTITUTION: The pellet of electric furnace dust, CDQ coke, etc., is charged in a first volatilization furnace 1A, the plating dross block in zinc plating equipment is charged in a second volatilization furnace 1B, and the insides of both furnaces are heated and kept at 900W1,100°C. Air or a reducing gas such as N2 is supplied to the Zn component volatilized, passed through a filter 4, and transferred to a duct 6, and the Zn component is collected by dust collectors 8A and 8B and recovered respectively as ZnO and Zn. Meanwhile, the iron and carbon-enriched residue from the bottoms of the furnaces 1A and 1B are supplied to a blast furnace and a sintering machine as the iron manufacturing raw material.
MARUKAWA YUJO
TATENO MASAKI
KISHINO SHIZUO
TANAKA KOGYO
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