Research On Burden Distribution Surface Profile Modeling And Charging Matrix Optimization In Blast Furnace Ironmaking

Blast fumace(BF)charging operation refers to the process of the burden(mainly ore and coke)in accordance with the set of charging system put into the BF throat in batches.Burden distribution operation is one of the four basic operating systems of the BF iron-making,and it is the most important means to adjust the upper part of the BF.The charging operation can change the distribution and surface shape formed by raw particles in the furnace throat,which affect the distribution of gas flow,gas utilization rate and the position and shape of the cohesive zone directly,it plays a key role for stable operation,high yield and high efficiency of the BF.However,BF is a high temperature,high pressure,confined large reactor,it is difficult to observe the internal directly.Subject to the measurement limit,surface shape information obtained by the charging operation is still difficult to detect and obtain,thus seriously affect the daily operation of charging operation.At present,the operator use the BF cross temperature and top infrared imaging detection means to estimate the surface shape in the BF throat,combined with their experience to make charging operation.The result shows that this kind of manual operation mode has a strong subjectivity and contingency,it is difficult to ensure the reasonable and efficient operation of the BF charging operation.Therefore,it’s urgent to establish the charging process model of BF to give operator an effective,reasonable guidance.In the view of these questions,supported by the National Natural Science Foundation of major projects "High performance control of the basic theory and key technology research for the operation of large sized blast furnace"(61290323)and "Experimental verification platform construction and application verification of large blast furnace high-performance operation control"(61290321),by analyzing the impact factors of the surface shape formed in charging process,the surface shape model has been established based on mechanism,and according to the established model,the optimization method of charging matrix is proposed.Finally,for the need of practical engineering application,the simulation and optimization system of BF been designed.the system can achieve the visualization of surface shape and the operation of the charging guidance.The main work as follows:(1)Based on the changing process mechanism and the principle of charge grain mechanics,by analyzing the factors affecting the BF charging process,the BF charging process model is established,including the initial state of charge model,the charge model in the center throat,the charge model in the chute and raw particles surface shape model.The model established in this thesis is simple and practical,which reduces the requirements of the modeling process on the number of sensors,and proposes a new method to build the surface shape model.At the same time,the radial ore to coke model of the charge was established according to the surface shape model.Finally,the model is validated by inverse-cross-temperature curve,and the results show that this model has good effect.(2)According to the surface shape model and the ideal surface shape in different furnace conditions,to minimize the next batch of raw particles of the surface shape and the ideal surface shape deviation as the optimization target,use the particle swarm optimization algorithm to find the best charging matrix(including the charging angle and the angle of the number of charging loops),so that the surface shape under this charging matrix close to the ideal surface shape This can guide the operator to carry out the charging operation of the charging matrix adjustment and optimization.(3)The thesis made No.2 BF of Liuzhou Iron and Steel Company as the research object,based on the above-mentioned model,the BF burden distribution simulation and optimization system is designed and developed.The system can be used for different types and sizes of BF,different charging operating system,showing the location of the throat raw particles surface shape of the profile,plan view and three-dimensional shape,it also can show the last two batches of raw particles radial ratio of ore and coke curve and the next batch suggested charging matrix.And the dynamic changes of surface shape under continuous charging process.At present,the system is put into use,the operation effect is good,provides strong technical support and guidance for No.2 BF of Liuzhou Iron and Steel Company burden distribution operation.