| At present,in order to obtain lower consumption index during the Blast Furnace production,besides improving the quality of coke and maintaining a reasonable charge structure,reasonable Blast Furnace operating system is the most economical and effective means of control.In actual production,Blast Furnace operators' treatment of"two gas-flows" has achieved good results in small and medium-sized Blast Furnaces(Blast Furnace capacity of 400m3,1000m3,2000m3,etc.),including the treatment of abnormal furnace conditions to ensure a faster recovery of the Blast Furnace.However,in order to ensure the stability of 5800m3 Blast Furnace,the original recovery and treatment is difficult to achieve the desired results.After a preliminary discussion and analysis of the reasons,it is considered that the understanding of the "two gas-flows" by Blast Furnace operators did not take appropriate measures to deal with a series of problems arising from the expansion of the furnace capacity.Instead,they used the old operating principle overemphasizing to loose the two gas-flows of the edge and the center.The specific performance is as follows:coke matrix set," more in two heads,less in the middle",mineral matrix set,"less in two heads,more in the middle." This matrix set,accompanied by the collapse of coke will inevitably lead to a thin coke window in the middle part.When the material layer drops to the soft melt belt,it seriously affects the stability of the airflow and the permeability of the Blast Furnace.In this paper,the history of the development of the charging system is discussed.At the same time,the aim is to use cold charging model to study the 5800 Blast Furnace.The model is designed according to 1/15 of the actual size and operating parameters of 5800m3 Blast Furnace in Shagang group,at the same time,by the analysis from the physical to the key parameters of the size,model batch weight,average particle size,the model chute rotation speed,the air quantity and pressure range,simulating the actual parameters of Blast Furnace as much as possible.Firstly,the cold charging model was used to study the influence of different inclination angles on the structure distribution of the material,and the distribution of center coke on the structure distribution of the material layers(with and without central coke),and the influence of different air volume levels and the matrix on the distribution of material layers(with and without coke)and so on.At the same time,by comparing the difference between giant Blast Furnaces with good indicators both at home and abroad,the paper studies the different pattern of the charging matrix during the furnace condition adjustment,that is,by analyzing and researching the the ratio of coke and ore with different edges and centers,and calculating surface distribution shape,as well as coke thickness,coke ratio and gas-flow distribution,it was showed that the protection of the middle part of the coke window thickness is the premise of stable operation.Meanwhile,the ore is not suitable for shop too wide.Thanks to the operation method on the basis of the above research "in the premise of ensuring the radial thickness of Blast Furnace coke window under the proper development of the two gas-flows",and through long-term communication with field operators and promotion of our research results,the 5800 Blast Furnace finally embarked on a normal and stable operation of the road,saving coke 27.8kg/tfe,and the yield increase of 1592t/d.The Blast Furnace gained stability for up to 2 months.It is also applied in No.1#2680 blast furnace and has achieved good results. |
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