材料期刊网

提出一种电硅热法生产300系列不锈钢母液新工艺，该工艺针对低品位红土镍矿二氧化硅含量高的特点，用矿热炉生产出高硅镍铁，然后利用高硅镍铁的硅还原铬粉矿中的铬、铁，得到镍铬不锈钢母液，再经成分、温度调整后转入AOD或VOD精炼工艺，生产出300系列不锈钢。因此，该工艺不仅有助于解决红土矿生产低硅镍铁的技术问题，而且可以直接使用铬精矿粉。物料与能量平衡计算结果表明，对比传统的“二步法”工艺，新工艺可降低原料成本6.3%～7.2%，降低综合能耗7.1%左右，降低CO2排放6.1%左右。台架试验结果表明，采用还原脱磷方法可将硅质量分数为20%左右的高硅镍铁中的磷质量分数降至0.03%以下，能满足新工艺的设计要求；脱磷后的高硅镍铁进行脱硅增铬，最终可得到磷、硅、碳质量分数符合不锈钢初炼钢水要求的镍铬不锈钢基料。

A new method has been developed to produce 300 series stainless steel,which is mainly for producing stain-less liquid steel with electrosilicothermic metallurgy. Ferronickel alloy with high silicon and low carbon content named as nickel-silicon ferroalloy is produced in submerged arc furnace(SAF)as the first step,then the slag containing chromium oxide and calcium oxide which come from refining furnace is charged into a shaking ladle together with liquid nickel-sili-con ferroalloy for pre-desilication and certain chromium reduction,finally,the liquid alloy with other chromium concen-trate and lime is charged into a refining furnace for final desilication to get the stainless liquid steel. In addition,a reduc-tive dephosphorization before the pre-desilcation process could be carried out if necessary. Argon Oxygen Decarburization (AOD)or Vacuum Oxygen Decarburization(VOD)process could then be followed to produce planned stainless steel. This process is different from the traditional one since it takes advantage of the characteristics of low grade lateritic ore with high SiO2 content. Besides,the utilization of low cost chromium concentrate is another effective way for the reduc-tion of production cost. Scale experimental results showed that the phosphorus content of nickel-silicon ferroalloy contain-ing about 20%silicon content could be decreased below 0.03%by use of reduction dephosphorization process and with the utilization of nickel-silicon ferroalloy,chromium concentrate and lime as the main raw materials. It is possible to pro-duce un-refined stainless liquid steel with electrosilicothermic process. Compared to traditional duplex process and based on matter and energy conservation,the total energy consumption,carbon dioxide emission and raw material cost in the new process could be decreased by about 7.1%,6.1%and 6.3%-7.2%,respectively.