Dry processing method and system for converter slag in copper smelting

Abstract

The present invention provides a processing method for converting slag ejected from a converter in a copper smelting process to raw materials for iron manufacture. The processing method is for converter slag containing 1 mass % or more of Cu produced in a copper smelting process. The processing method comprises a step of charging the converter slag in a reduction furnace, and a step of conducting a heat reduction of a zinc content and a copper content contained in the slag and removing a reduced zinc by volatilization in the reduction furnace. The removal of the reduced zinc by volatilization is conducted in a condition in which an air fuel ratio of a volume of air blowing to an input of a reductant is controlled to 0.25 to 1.0.

1 . A processing method for converter slag containing 1 mass % or more of Cu produced in a copper smelting process, comprising:
 a step of charging the converter slag in a reduction furnace, and   a step of conducting a heat reduction of a zinc content and a copper content contained in the slag and removing a reduced zinc by volatilization in the reduction furnace, and   wherein the removal of the reduced zinc by volatilization is conducted in a condition in which an air fuel ratio of a volume of air blowing to an input of a reductant is controlled to 0.25 to 1.0.   
     
     
         2 . A processing method for converter slag containing 1 mass % or more of Cu produced in a copper smelting process, comprising:
 a step of charging the converter slag in a reduction furnace,   a step of conducting a heat reduction of a zinc content and a copper content contained in the slag and removing a reduced zinc by volatilization in the reduction furnace, and   a step of separating a reduced copper by a precipitation from the slag, and   wherein the removal of the reduced zinc by volatilization is conducted in a condition in which an air fuel ratio of a volume of air blowing to an input of a reductant is controlled to 0.25 to 1.0.   
     
     
         3 . A processing method for converter slag containing 1 mass % or more of Cu produced in a copper smelting process, comprising:
 a step of charging the converter slag in a reduction furnace,   a step of conducting a heat reduction of a zinc content and a copper content contained in the slag and removing a reduced zinc by volatilization in the reduction furnace,   a step of transferring a reduced copper with the slag from the reduction furnace to a settling furnace, and   a step of separating the reduced copper by a precipitation from the slag in the settling furnace, and   wherein the removal of the reduced zinc by volatilization is conducted in a condition in which an air fuel ratio of a volume of air blowing to an input of a reductant is controlled to 0.25 to 1.0.   
     
     
         4 . The processing method of  claim 1 , wherein the converter slag is held in a melt state, and the converter slag is charged in the reduction furnace from a holding furnace for controlling a supply of the converter slag to be supplied to the reduction furnace. 
     
     
         5 . The processing method of  claim 1 , further comprising a step of conducting a preliminary reduction of the converter slag before supplying to the reduction furnace. 
     
     
         6 . The processing method of  claim 5 , wherein the preliminary reduction is conducted in the holding furnace. 
     
     
         7 . The processing method of  claim 1 , further comprising a step of crushing the slag after the step of separating the reduced copper by a precipitation from the slag. 
     
     
         8 . The processing method of  claim 1 , wherein Fe 3 O 4  contained in the slag is heat-reduced to FeO in the reduction furnace. 
     
     
         9 . The processing method of  claim 4 , wherein the reductant is put in the slag flowing for the reduction furnace from the holding furnace. 
     
     
         10 . The processing method of  claim 4 , wherein the reductant is put in the slag flowing for the holding furnace from the converter. 
     
     
         11 . The processing method of  claim 1 , wherein the reductant used for the reduction of the slag in the reduction furnace is 1 to 10 mass % of coke to mass of the slag. 
     
     
         12 . A processing system for converter slag containing 1 mass % or more of Cu produced in a copper smelting process, comprising:
 a reduction furnace in which a heat reduction of a zinc content and a copper content contained in the converter slag is conducted,   an exhaust means installed in the reduction furnace for removing the volatilized reduced zinc, and   a discharge means for discharging the reduced copper separated by a precipitation from the reduction furnace, and   wherein the removal of the reduced zinc by volatilization is conducted in a condition in which an air fuel ratio of a volume of air blowing to an input of a reductant is controlled to 0.25 to 1.0.   
     
     
         13 . The system of  claim 12 , further comprising a slag crush processing means and a transfer means for transferring the slag ejected from the reduction furnace to the slag crush processing means. 
     
     
         14 . A processing system for converter slag containing 1 mass % or more of Cu produced in a copper smelting process, comprising:
 a reduction furnace in which a heat reduction of a zinc content and a copper content contained in the converter slag is conducted,   an exhaust means installed in the reduction furnace for removing the volatilized reduced zinc,   a settling furnace for separating a reduced copper by a precipitation from the slag,   a transfer means for transferring the slag ejected from the reduction furnace to the settling furnace, and   a discharge means for discharging the reduced copper separated by a precipitation from the settling furnace, and   wherein the removal of the reduced zinc by volatilization is conducted in a condition in which an air fuel ratio of a volume of air blowing to an input of a reductant is controlled to 0.25 to 1.0.   
     
     
         15 . The system of  claim 14 , further comprising a slag crush processing means and a transfer means for transferring the slag ejected from the settling furnace to the slag crush processing means. 
     
     
         16 . The system of  claim 12 , further comprising:
 a holding furnace for holding the converter slag in a melt state and controlling a supply of the converter slag to be supplied to the reduction furnace, and   a transfer means for transferring the converter slag ejected from the holding furnace to the reduction furnace.   
     
     
         17 . The system of  claim 12 , further comprising a preliminary reduction furnace for conducting a preliminary reduction of the converter slag before supplying to the reduction furnace. 
     
     
         18 . The system of  claim 17 , wherein the holding furnace doubles as the preliminary reduction furnace. 
     
     
         19 . The system of  claim 14 , further comprising:
 a holding furnace for holding the converter slag in a melt state and controlling a supply of the converter slag to be supplied to the reduction furnace, and   a transfer means for transferring the converter slag ejected from the holding furnace to the reduction furnace.   
     
     
         20 . The system of  claim 14 , further comprising a preliminary reduction furnace for conducting a preliminary reduction of the converter slag before supplying to the reduction furnace.