马钢4000m^3高炉喷吹煤粉燃烧性能研究与应用

Study and application on combustibility of pulverized coal injection at 4000m^3 BF of Masteel

提高高炉喷煤比对降低焦比有着重要影响。以6种原煤煤粉、4种混合煤粉为原料,进行煤粉工业及煤岩组分分析、热重分析。研究了富氧率、煤粉粒度、风温对煤粉燃烧率的影响。结果表明,富氧率提高,对烟煤、软煤的燃烧率作用较大,对硬煤燃烧率作用较小;粒度对烟煤和软煤的燃烧率影响较大,硬煤的燃烧率只有在其粒度大于0.074mm的比例大于65%时有明显提高;热风温度升高,烟煤的燃烧率提高最大,对软煤的燃烧率有一定作用,对硬煤的燃烧率作用不大;在配煤方面,应该适当增加软煤配比,降低硬煤配比,稳定烟煤配比。马钢4000m^3高炉煤比从140增加到160kg/t时,除尘灰中的未燃煤粉增加2.22kg/t。

Increasing the quantity of powdered coal injection in blast furnace has very important effect on reducing coke ratio.Six kinds of raw coal pulverized coal and four kinds of mixed pulverized coal of blast furnace were taken ,then the experimental materials,the industrial analysis,the coal petrography analysis and the thermal gravimetric analysis were studied in this experiment.Besides,the effects of oxygen enrichment,granularity,air temperature on the combustibility of pulverized coal were studied as well.The results showed that with the increasing of the oxygen enrichment,it has a great effect on the combustibility of bituminous coal and soft coal and has little effect on the combustibility of hard coal.The granularity has a great influence on the combustibility of bituminous coal and soft coal,and the combustibility of hard coal was significantly improved only when the 0.074 mm of coal was more than 65%.With the temperature of the hot air increasing,the combustibility of bituminous coal was increased most.In addition,it also has a certain effect on the soft coal combustibility and small effect on the combustibility of hard coal.In coal blending,the ratio of soft coal should be increased,the ratio of hard coal should be reduced and the ratio of bituminous coal should be stabilize.When the coal rate of the 4 000 m^3 blast furnace increased from 140 to 160 kg/t in Masteel,the increase of unburned pulverized coal in the blast furnace dust was only 2.22 kg/t.