Study On Optimization Of Meishan Steel Blast Furnace Pulverized Coal Injection

Recently, with the shortage of coking coal resource and the increase of coking environmental protection pressure, Mei steel in order to reduce the cost of iron making process, hopesto increase the ratio of pulverized coal instead of part of coke in the blast furnace. In order to make the blowing effect better, specially doing the corresponding experimental testof increasing coal ratio, so as to determine the reasonable injection coal and spray blowing coal blending scheme.In Mei steel pulverized coal, the test of three spray blowing coal industrial analysis, performance based detection, analyzes the effects of different factors on pulverized coal burning and under different atmosphere conditions the pulverized coals 'pyrolysis characteristics.The effects of powder coal granularity, air temperature, oxygen enrichment and coal ratio level on of the burning rate of pulverized coal were studied.Test showed that the Shenhua coal belongs to strong explosive coal without preheating, when coal preheating 250?,the explosion is enhancedsignificantly; When the oxygen content of the medium in the 2%-21%, the pulverized coal show a weak deflagration. when the medium oxygen content reach more than 25%, the coal burning has stronglyretunedfire, the coal powder exhibits strongdeflagration;The pulverized coal particle becomes smaller, the stronger the deflagration of the pulverized coal; The higher the content of volatile, the stronger the coal dust explosion; the pyrolysis characteristics of the pulverized coal in pure oxygen atmosphere is better than air atmosphere. The main factors of pulverized coal burning rate are: coal ratio level, oxygen enrichment ratio, hot blast temperature, particle size of pulverized coal.The following conclusions are obtained by the experiment of the above factors.(1)When coal ratio is increased from 100kg/t to 250kg/t, the burning rate decreases from 61.61% to 46.10%, and the coal ratio increases by 10 kg/t, and the pulverized coal burning rate will be reduced by about 1%.(2)Increasing the oxygen enrichment rate in the blast can obviously improve the burning rate of the pulverized coal, the oxygen enrichment rate increased from 0% to 8%, and its burning rate increased from 49.02% to 62.89%, and with the increase of oxygen enrichment rate, the rate of burning rate decreased.(3)The influence of hot air temperature on the burning rate of pulverized coal is remarkable, and when the hot air temperature rises from 1100? to 1300?, the burning rate rises from 50.33% to 56.32%, and the burning rate of pulverized coal increases slowly with the increasing of the hot air temperature.(4)In terms of the size of pulverized coal, when the size of the pulverized coal increases to 300 mesh, the burning rate of the pulverized coal is increased from 51.61% to 57.9%, and the smaller the pulverized coal is, the higher the burning rate is. In the coal mixture of bituminous coal and anthracite, the mixtures of the burning rate is higher than single anthracite.