Study On Optimization And Exploitation Of Pulverized Coal Injection In Blast Furnace Of Chongqing I &S Co.

During many years researching and practisesing, the technology of coal powder injection in Chongqing I&S Co. has been advanced. Based on studying and analysising the existing problems of injection technology in Chongqing I&S Co., the utilization of coal powder in blast furnace has been researched. According to smelting conditions and rules of Chongqing I&S Co., the process optimizing, injection quantity and influencing factor of injection process have been studied. The proper processing parameters ans injection rules have been proposed.The coal powder injection in Chongqing I&S Co. is of very importance. By using this technology, the cost of pig iron can be reduced and profits can be promoted. Moreover, the integrated coke ratio can be reduced so that the melting conditions of blast furnace can be improved.The load of coke increased when the injection quantity enhanced. That made airflow developed. Along with the increase of injection quantity, the central CO2 descended and the marginal CO2 ascended. This situation was good for the development of central airflow. Moreover, the temperature in hearth ascended so that the temperature was driven to uniformity. Furthermore, indirect reduction has been improved then the temperature in hearth increased. Besides, the temperature of combution belt reduced and the contents of silicon reduced after coal powder injected.The injection quantity has been promoted to 110 Kg/tFe. The working conditions of furnace hearth has been improved, so the blast furnace performed stably. The rate of driving and yield were increased.Combution rate of bituminous coal was higher than that of anthracite coal. So the promotion of combution rate increased along with mixture ratio of bituminous coal. The reaction index was in the highest level when the content of bituminous coal was between 45% to 50%. Considering all influencing factor, the proper composition of injection coal is that bituminous coal is 45% to 50% and the anthracite coal is 50% to 55%.The main ways to improve the coal ratio of blast furnace are mixing properly, reducing the alkali load, improving the purity, promoting the structure of mixing coal, advanced the air temperature, optimizing the furnace operation, and so on.Based on the research of injection in Chongqing I&S Co., the ways to optimize the blast furnace operation are promoting the purity of furnace charges, improving the structure of charges and the charging rules, stablizing and increasing the air temperature, and promoting the ratio of oxygen-enriched to 2%. Under this conditions, the coal ratio can be increased to over 120 Kg/tFe and the integrated coke ratio can be reduced to 520 kg/tFe.