高炉喷吹不同比例混合煤的效果研究

Research on effect of pulverized coal injection with different blending ratios into blast furnace

将炼铁厂高炉喷吹所使用的无烟煤、烟煤、褐煤以不同配比制取混合煤样,对其着火点、可磨性以及燃烧性能进行研究。实验结果表明:每加入5%褐煤后会降低混合煤样的着火点4℃左右;在烟煤、无烟煤混合的煤样中加入15%褐煤会使可磨性指数加权值减少7,但实际值降低了14。加入褐煤后,2种配煤方案中煤粉燃烧性能的主要影响为降低着火温度、提供良好的燃烧环境,对燃尽温度的影响并不明显。在无烟煤中加入大量褐煤会使热值不足、磨煤机能耗较高,且还会给安全生产带来一定影响,相较之下在烟煤与无烟煤的混煤中加入褐煤能够取得更良好的喷煤效果。

A research on ignition point,grindability and combustibility was conducted for blend prepared with different proportions of anthracite,bituminous coal and lignite injected into blast furnace.The experimental results show:the ignition point of blend is lowered by about 4℃after addition of 5 mass%lignite;the weighted grindability value of blend of bituminous coal and anthracite is reduced by 7 after addition of 15 mass%lignite while the actual grindability value is reduced by 14.The main effect of the addition of lignite on the combustion performance of two types of blend is to reduce the ignition temperature and provide a satisfactory combustion environment,but the effect on the burnout temperature is not obvious.When a large proportion of lignite was added into anthracite,it would result in insufficient calorific value and high energy consumption of coal pulverizer and also affect safety production to some extent.By contrast,a better coal injection effect was achieved by adding lignite into the blend of bituminous coal and anthracite.