Apparatus and process for the production of fire-refined blister copper

Abstract

Fire-refined blister copper is produced from copper concentrate by a process comprising: A. melting and oxidizing the copper concentrate in a smelting furnace to produce molten matte and slag, and to separate one from the other; B. removing the molten matte from the smelting furnace; C. solidifying the molten matte; D. injecting the solidified matte into a converting furnace in which the matte is converted to blister copper and slag; and E. transfering the blister copper from the converting furnace to an anode furnace to produce fire-refined blister copper. After the fire-refined blister copper is produced in the anode furnace, it is typically transferred to an anode casting wheel on which it is converted to copper anodes suitable for subsequent electrolytic refining to cathode copper.

What is claimed is: 
     
       1. A process for smelting copper concentrates containing sulfur values to produce fire-refined blister copper as a principal product and slag and sulfur dioxide as by-products, the process comprising: A. melting and oxidizing the copper concentrate in a smelting furnace to produce molten matte, molten slag, and gaseous sulfur dioxide;   B. removing the molten matte, molten slag and gaseous sulfur dioxide from the smelting furnace in separate streams;   C. solidifying the molten matte;   D. feeding the solidified matte into a converting furnace in which the matte is converted to molten blister copper, molten slag and gaseous sulfur dioxide;   E. removing the molten blister copper, molten slag and gaseous sulfur dioxide from the converting furnace in separate streams;   F. transferring the blister copper from the converting furnace to an anode furnace through an arrangement of covered launders .[.and a covered divertor.].; and   G. fire-refining the blister copper in the anode furnace to produce anode copper and sulfur dioxide; the process conducted in a manner such that less than about 2 percent of the sulfur values in the copper concentrate and less than about 5 kilograms per metric ton of copper of sulfur dioxide are released to the enviroment.   
     
     
       2. The process of claim 1 in which the copper concentrate is melted and oxidized through the action of a flash smelting furnace. 
     
     
       3. The process of claim 2 in which the molten matte is removed from the smelting furnace through a taphole in a sidewall of the furnace, and then transferred through a covered launder to solidification means. 
     
     
       4. The process of claim 3 in which the molten matte is poured from the covered launder through a curtain of water to form granular, sand-like particles of matte. 
     
     
       5. The process of claim 4 in which the solid matte is transferred to and held in a storage area before used as a feed to the converting furnace. 
     
     
       6. The process of claim 5 in which the solid matte is dried and reduced in size to dust-like particles before fed to the converting furnace. 
     
     
       7. The process of claim 6 in which the solid matte is converted to blister copper through the action of a flash converting furnace. 
     
     
       8. The process of claim 7 in which the blister copper is removed from the converting furnace through a continuous blister tapper which is in fluid communication with the furnace. 
     
     
       9. The process of claim 8 in which the blister copper is routed from the continuous blister tapper through the launder .[.and divertor.]. arrangement.Iadd., into and through a divertor, .Iaddend.to one of two rotary anode furnaces operated in tandem. 
     
     
       10. The process of claim 8 in which the blister copper is routed from the continuous blister tapper through a covered launder to a holding furnace in which it is further oxidized before transfer through a launder and divertor arrangement to one of two rotary anode furnaces operated in tandem. 
     
     
       11. An apparatus for producing fire-refined blister copper as a principal product and slag and sulfur dioxide as by-products from copper concentrates containing sulfur values, the apparatus comprising: A. a flash smelting furnace for melting and oxidizing copper concentrate to produce molten matte, molten slag, and gaseous sulfur dioxide;   B. solidification means for converting the molten matter into solid matte;   C. covered launders for transferring the molten matte from the flash smelting furnace to the solidification means;   D. means for capturing the gaseous sulfur dioxide and processing it for use as a feed to an acid plant for the production of sulfuric acid;   E. a flash converting furnace for melting and oxidizing solidified matte to blister copper, molten slag, and gaseous sulfur dioxide;   F. means for transferring the solidified matte to the flash converting furnace;   G. an anode furnace for fire-refining the blister copper to a quality suitable for casing copper anodes;   H. a covered launder .[.and divertor.]. arrangement for transferring the blister copper from the flash converting furnace to the anode furnace; and   I. means for capturing the gaseous sulfur dioxide and processing it for use as a feed to an acid plant for the production of sulfuric acid.   
     
     
       12. The apparatus of claim 11 further comprising means for drying and sizing the copper concentrate prior to its introduction into the flash smelting furnace. 
     
     
       13. The apparatus of claim 12 in which the drying means is a rotary kiln. 
     
     
       14. The apparatus of claim 13 in which the solidification means is a water granulation apparatus. 
     
     
       15. The apparatus of claim 14 in which the means for capturing the gaseous sulfur dioxide includes a waste heat boiler, electrostatic precipitator and a wet scrubber train. 
     
     
       16. The apparatus of claim 15 further comprising pneumatic transfer means for transporting the solidified matte from the water granulator to the storage area, and from the storage area to the converting furnace. 
     
     
       17. The apparatus of claim 16 further comprising apparatus for drying and size reducing the solidified matte before its use as a feed to the converting furnace. 
     
     
       18. The apparatus of claim 17 .Iadd.in which the covered launder arrangement includes a diverter, and .Iaddend.in which the anode furnace comprises two rotary furnaces operated in tandem. 
     
     
       19. The apparatus of claim 18 further comprising a holding furnace positioned between the converting furnace and the anode furnace. 
     
     
       20. The apparatus of claim 17 in which the anode furnace is a nonrotary furnace comprising an oxidation zone and reduction zone, the zones divided by a dam.