| 摘要 |
<p>830,592. Reducing iron ore. INLAND STEEL CO. May 27, 1958, No. 16894/58.. Class 72 The reduction of iron oxide comprises reducing by a gas and melting in a hearth zone wherein oxygen rich gas containing at least 80% oxygen and fuel having an H : C atomic ratio of less than 3 are burnt, the combustion gas having a CO 2 : CO ratio of 0.7 to 3, reforming the gas by the introduction of additional fuel and oxygen in a reforming zone to produce a reformed gas with a CO:CO 2 ratio of at least 7, an H 2 :CO 2 ratio not greater than 1 and a content of not more than 10% CO 2 , reducing a major portion of the iron oxide ore with the gas between 900‹ and 1800‹F. the mixture of incompletely reduced ore being melted in the hearth zone with a surfeit of carbonaceous material to complete the reduction. As shown, incompletely reduced ore, coal, and oxygen are introduced to hearth zone 10 through lines 11, 39, and 13 with combustion gas, slag, and metal leave by lines 19, 18 and 17. The gas goes. to reformer 21 to which oxygen and coal are supplied drawn through line 31 to pump 32, repasses through line 22, and reformed gas goes to heat exchanger 26 where it is cooled prior to the removal of ash by washing with liquid sprays in washer 24. Clean gas is drawn through line 31 to pump 32 repasses through the heat exchanger, and enters the reducing column 12 which it leaves through line 38. Fresh ore is dried at 36 and enters the reducing column through line 37. The quantity of gas produced in the hearth zone, together with the additional quantity produced on reformation, should equal the quantity of gas required by the reducing column. U.S.A. Specifications 2,526,658 and 2,750,277 are referred to.</p> |
