| 摘要 |
<p>1474624 Smelting pelletized ores R F OBENCHAIN 14 May 1974 [31 May 1973] 21303/74 Heading C7D Molten metal, e.g. Cr, Fe-Mn, or preferably Fe, is produced in a cupola from pellets containing metal oxide and sufficient carbonaceous material sufficient to effect complete reduction of the oxide. Alternate layers of coke and pellets are charged to a cupola 1 above a coke bed 7 heated by blasts of air, O 2 or preferably O 2 -enriched air through tuyeres 8. A flux, e.g. CaO, CaCO 3 , MgCa(CO 3 ) 2 , Na 2 CO 3 or CaF 2 is added to the charge, together with a desulphurisation agent, e.g. soda ash, CaC2, if required. The pellets are formed from particulate ore, e.g. fines, furnace dust, mill scale, with e.g. fine coal, coke, petroleum coke, and water, with a binder, e.g. cement, lime, if extra strength is required, e.g. for the initial charge. The pellets are preferably formed on a disc 10 and are fed by conveyers to the cupola, during which the pellets may be dried by off-gases from hoods 24, 25. The off-gases may also be used to pre-heat the air and/or O 2 blast, e.g. to 2600‹F. Air and/or O 2 , and optionally natural gas, petroleum or powdered coal is introduced through tuyeres 8a, 8b to acid the heating of the coke. The molten metal containing 0À02 to 4% C falls through the coke bed and is tapped at 9. Scrap and pig iron may also be added to the charge.</p> |
