邢钢烧结原料基础特性及优化配矿试验研究

采用微型烧结试验装置,对邢钢烧结厂常用的7种铁矿粉的基础特性进行了系统研究。结果表明:7种铁矿粉的同化性能、流动性性能、粘结性强度、铁酸钙生成特性、吸水性有较大差异。杂料的同化性最好,同化温度为1 200℃;混合矿的流动性最好,流动性指数为1.69;低硅酸精粉的粘结相强度最高,为4 548 N;杂料的吸水性最高,为36.32%。基于邢钢现场原料条件,进行了烧结优化配矿试验研究,通过降低混合矿中澳矿配比、提高本地碱精粉配比,混合料的基础特性有一定改善,其中同化温度提高了20℃,流动性指数降低到1.27,粘结相强度提高了281 N,最大吸水率降低了1个百分点。烧结杯试验结果表明:垂直烧结速度有所改善,成品率提高了4.5个百分点,成品烧结矿转鼓强度提高了2个百分点,低温还原粉化指数提高了3个百分点,还原性能、荷重软化性能均有所改善。研究结果为邢钢提高本地矿配比、优化配矿、改善烧结矿质量提供了理论依据。

Experimental Study on Basic Characteristics and Ore-blending Optimization of Xingtai Steel Raw Materials for Sintering

The basic characteristics of 7 kinds of iron ore powders for Xingtai Steel Sintering Plant were studied systematically with micro sintering experiment device. The results show that 7 kinds of powders are quite different in assimilation performance, flowability, cohesiveness, calcium ferrite formation features and water absorption. The sundries exhibit the best assimilation performance at the temperature of 1 200 ℃, while the mixed ore has the best flowability, with a flowability index at 1.69. The binding phase of low silica powder shows the highest strength of 4 548 N, and the sundries have the highest water absorption of 36. 32%. Experiments on ore?blending optimization for sintering process were carried out on this basis. By reducing Australia′s ore ratio in the mixed ore and increasing the ratio of local alkali fine powder, the basic characteristics of the mixture are improved, with the assimilation temperature raised by 20 ℃, the flowability index falling to 1.27, the strength of the binding phase increased by 281 N and water absorption reduced by 1 percentage point. The sinter pot test shows that the vertical sintering speed is improved while the final product yield, drum strength, as well as low?temperature reduction degradation index are all increased by 4.5 percentage points, 2 percentage points, and 3 percentage points, respectively, with both reduction property and load softening property improved. These research results can be taken as the theoretical guidance for iron?ore blending optimization and improvement of sintered ore quality in Xingtai Steel Sintering Plant.