Method of recovery of zinc and other metals from metallurgical fines

Abstract

A method and recovering method of recovering zinc oxides and other metal oxides having an injection chamber where a mixture of natural gas and oxygen is formed and then ignited to form high temperature combustion gases of greater than 2000° C. with a high concentration of carbon monoxide. Then, the mixture is transported through a quiescent chamber to a feed chamber where the ignited high temperature combustion gases are mixed with finely divided material, including EAF dust. The mixture is transported to a reaction chamber, wherein zinc vapor and other metal vapors and molten slag particles are formed. The zinc vapor and other metal vapors are separated from the molten slag particles and transported to an insulated plenum. Zinc vapor and other metal vapors are mixed with air and become airborne zinc oxide and other metal oxides. The airborne zinc oxide and other metal oxides are collected.

What is claimed is: 
     
         1 . A method of recovering zinc oxide and other metal oxides from metallurgical fines, comprising:
 a. forming in an injection chamber a mixture of natural gas and oxygen and then igniting the mixture to form high temperature combustion gases of greater than 2000° C. with a high concentration of carbon monoxide;   b. transporting the ignited high temperature combustion gases through a quiescent chamber surrounded by a cooling jacket and located below the injection chamber;   c. transporting the ignited high temperature combustion gases from the quiescent chamber to a feed chamber surrounded by a cooling jacket and located below the quiescent chamber;   d. forming in the feed chamber a mixture of the ignited high temperature combustion gases with injected finely divided material including EAF dust;   e. transporting the mixture of the ignited high temperature combustion gases with injected finely divided material including EAF dust to a reaction chamber surrounded by a cooling jacket, wherein carbon monoxide in the ignited high temperature combustion gases react with metal compounds in the finely divided material forming zinc vapor and other metal vapors and molten slag particles;   f. transporting said mixture, including the zinc vapor and other metal vapors and slag particles, from the reaction chamber through a transition piece to a slag separation chamber surrounded by a cooling jacket and located tangentially to the reaction chamber, wherein the zinc vapor and other metal vapors are separated from the molten slag particles;   g. transporting the zinc vapor and other metal vapors to an insulated plenum, wherein the zinc vapor and other metal vapors are mixed with air and become airborne zinc oxide and other metal oxides; and   h. transporting the airborne zinc oxide and other metal oxides from the insulated plenum to a filter baghouse where zinc and other metal oxides are collected and remaining gases are released to the atmosphere.   
     
     
         2 . The method of recovering zinc oxides and other metals oxides as claimed in  claim 1 , wherein components of the injection chamber are made of copper. 
     
     
         3 . The method of recovering zinc oxides and other metals oxides as claimed in  claim 1 , wherein components of the quiescent chamber are made of copper. 
     
     
         4 . The method of recovering zinc oxides and other metals oxides as claimed in  claim 1 , wherein components of the feed chamber are made of copper. 
     
     
         5 . The method of recovering zinc oxides and other metals oxides as claimed in  claim 1 , wherein the quiescent chamber is an extension of the injection chamber. 
     
     
         6 . The method of recovering zinc oxides and other metals oxides as claimed in  claim 1 , wherein the quiescent chamber is an extension of the feed chamber. 
     
     
         7 . The method of recovering zinc oxides and other metals oxides as claimed in  claim 1  further comprising a tap in the slag separation chamber to remove collected slag from the slag separation chamber. 
     
     
         8 . The method of recovering zinc oxides and other metals oxides as claimed in  claim 7  further comprising a heating unit provided in the slag separation chamber inhibiting air from entering the slag separation chamber and maintaining slag fluidity. 
     
     
         9 . A apparatus for recovering zinc oxide and other metal oxides from metallurgical fines, comprising:
 a. an injection chamber, where natural gas and oxygen are mixed and then ignited to form high temperature combustion gases of greater than 2000° C. with a high concentration of carbon monoxide;   b. a quiescent chamber surrounded by a cooling jacket, where the ignited high temperature combustion gases are transported to;   c. a feed chamber surrounded by a cooling jacket, where the ignited high temperature combustion gases are mixed with finely divided material including EAF dust;   d. a reaction chamber surrounded by a cooling jacket, where carbon monoxide in the ignited high temperature combustion gases react with metal compounds in the finely divided material forming zinc vapor and other metal vapors and molten slag particles;   e. a slag separation chamber surrounded by a cooling jacket and tangentially to the reaction chamber, where the zinc vapor and other metal vapors are separated from molten slag particles;   f. an insulated plenum, where the zinc vapor and other metal vapors are mixed with air and become airborne zinc oxide and other metal oxides; and   g. a filter baghouse, where the zinc oxide and other metal oxides are collected and remaining gases are released to the atmosphere.   
     
     
         10 . The apparatus for recovering zinc oxide and other metal oxides as claimed in  claim 9 , wherein components of the injection chamber are made of copper. 
     
     
         11 . The apparatus of recovering zinc oxides and other metals oxides as claimed in  claim 9 , wherein components of the quiescent chamber are made of copper. 
     
     
         12 . The apparatus of recovering zinc oxides and other metals oxides as claimed in  claim 9 , wherein components of the feed chamber are made of copper. 
     
     
         13 . The apparatus of recovering zinc oxides and other metals oxides as claimed in  claim 9 , wherein the quiescent chamber is an extension of the injection chamber. 
     
     
         14 . The apparatus of recovering zinc oxides and other metals oxides as claimed in  claim 9 , wherein the quiescent chamber is an extension of the feed chamber. 
     
     
         15 . The apparatus of recovering zinc oxides and other metals oxides as claimed in  claim 9  further comprising a tap in the slag separation chamber to remove collected slag from the slag separation chamber. 
     
     
         16 . The apparatus of recovering zinc oxides and other metals oxides as claimed in  claim 15  further comprising a heating unit provided in the slag separation chamber inhibiting air from entering the slag separation chamber and maintaining slag fluidity.