| 摘要 |
<p><PICT:0991579/C6-C7/1> Pig iron is produced in a furnace rotating at not less than 10 r.p.m. about an axis inclined at not more than 45 degrees to the horizontal by forming therein a body of slag and carbonaceous material at a temperature not exceeding 1450 DEG C. and supplying on top of said body comminuted ore and carbonaceous reducing agent in such proportions that a layer of molten iron containing at least 2% and preferably 3% of carbon is formed below the slag. Oxygen or oxygen-rich gas is blown in above the slag in such a way that the reducing conditions at the bath surface are not impaired, the carbon monoxide evolved in the reduction layer burning therewith to provide the necessary heat for the process. An acidic slag may be used or, when phosphorus-rich materials are to be reduced, carbonates and/or oxides of calcium and/or magnesium are added together with pieces of carbonaceous matter sufficiently large to float on the slag, and the conditions are then so regulated that the iron oxide content of the slag is at least 2% calculated as iron. The iron ore charged may have been partially pre-reduced to metallic iron, and the process may be operated either continuously or batchwise. As illustrated, rotary furnace 1 is charged with ore and reducing agent from hopper 23 by a blast of air or natural gas from pipe 24, thereby forming metal layer 5, slag layer 6 and reaction layer 7. Oxygen is blown in through pipes 26, 27, and the exhaust gases escape through opening 11.</p> |
