The Optimization And Practice Of Coal Injection Ratio Of No.5 Blast Furnace In Guofeng Steel

In this paper,an innovation of equipment upgrading at Guofeng No.5 blast furnace was investigated,according to the clarity of technological process and the application of Lean Six Sigma method to select key factors.These factors were examined by Minitab software.A variation between coal injection and other indexes was analyzed and the reason why it has deterred coal injection in BF to rise was found,by means of comparing oral fuel with slag-metal ingredient and integrating field data and BF daily sheet.Some conclusions,therefore,were drawn as follow:(1)Coal ratio and theoretical combustion temperature,Guofeng 5 blast furnace in 140 kg/tHM coal ratio when the temperature increases with the theory of coal ratio increases;when the coal ratio exceeds 140 kg/tHM,a reverse change.According to the existing situation of No.5 blast furnace smelting,such as to ensure the temperature limit of 2050? to the theory.Coal ratio should not exceed 175 kg/tHM.(2)Coal ratio and blast kinetic energy,coal ratio change and blast kinetic energy is proportional to,the coal ratio increased after the drum wind energy shortage,replaced the 9 larger diameter tuyere,improve blast kinetic energy.(3)Coal ratio on the raceway shape and the influence of dead material column height,the mathematical model,it shows the depth of the raceway is 1.532 m,deadman height of 1.268m.coal depth ratio increases,and deadman height decreased.(4)The relationship between the coal ratio and the change of wind temperature,according to the regional heat balance relationship,the optimization of the equipment improvement and operation system is made.The maximum coal ratio is 172.04 kg/tHM.when the air temperature is increased by 1170?.(5)Coal and oxygen enriched coal transformation,with ratio increasing,but due to lack of oxygen limitation,the existing 5000 m3/h fand enriched conditions,coal ratio should be limited to the following 170 kg/tHM.(6)the utilization rate of coal ratio relationship with gas,gas and coal utilization ratio is inversely proportional,coal ratio will increase gas utilization rate,to ensure the reasonable distribution of gas flow,coal ratio should be controlled at 150?160 kg/tHM,the gas utilization rate of not less than 45%.On the basis of the above research,the price difference between coke and coal,the comprehensive efficiency index concept,through coal ratio changes,different coal ratio,change cost of pig iron blast furnace.Based on the above research and analysis,finally to Feng No.5 blast furnace after overhaul,the best coal ratio is about 155 kg/tHM.And summed up according to the different calculation methods of optimal ratio of blast furnace coal injection,to provide guidance for others.Finally,in accordance with the national Guofeng 5 blast furnace,the existing raw fuel,equipment,operating system,and so on,formulate corresponding improvement program for rectification.