TAILIEUCHUNG - Extractive Metallurgy of Copper Part 10
Tham khảo tài liệu 'extractive metallurgy of copper part 10', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | CHAPTER 15 Fire Refining and Casting of Anodes Sulfur and Oxygen Removal Virtually all the copper produced by smelting converting is subsequently electrorefined. It must therefore be suitable for casting into thin strong smooth anodes for interleaving with cathodes in electrorefining cells Fig. . This requires that the copper be fire refined to remove most of its sulfur and oxygen. The molten blister copper from Peirce-Smith converting contains s and o Chapter 9. The copper from single-step smelting and continuous converting contains to o and up to 1 s Chapters 10 and 12. At these levels the dissolved sulfur and oxygen would combine during solidification to form bubbles blisters of so2 in newly cast anodes - making them weak and bumpy. In stoichiometric terms mass dissolved sulfur and mass dissolved oxygen would combine to produce about 2 cm3 of so2 1083 C per cm3 of copper. Fire refining removes sulfur and oxygen from liquid blister copper by a air-oxidation removal of sulfur as so2 to s then b hydrocarbon-reduction removal of oxygen as co and H2O g to o. Sulfur and oxygen contents at the various stages of fire refining are summarized in Table . Industrial Methods of Fire Refining Fire refining is carried out in rotary refining furnaces resembling Peirce-Smith 47 248 Extractive Metallurgy of Copper CHARGING MOUTH AND GAS OUTLET Fig. . Rotary refining anode filmace end and front views after McKerrow and Pannell 1972 . The furnaces are typically 3 to 5 m diameter and 9 to 14 m long inside the steel shell. GRAIN MAGNESITE GROUT Fig. . Detail of anode furnace tuyere after McKerrow and Pannell 1972 . Note the two concentric pipes separated by castable refractory which permit easy replacement of the inside pipe as it wears back. The inside pipe protrudes into the molten copper to prevent seepage of gas back through the refractory wall of the furnace. Reprinted by permission of CIM Montreal Canada. Fire .
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