Modeling Research On Granulation Process Of Sintered Iron Ore Fines Based On The EDEM

Under the background of the new normal economy and the "Made in China 2025"strategy,the steel industry is seeking major changes.How to optimize the production process,use raw materials efficiently,and improve production efficiency have become increasingly important issues.Iron ore fines sintering is an important part of the iron making process,and iron ore fines granulation is an important part of ensuring the sintering process qualityIn this paper,the discrete element simulation software EDEM is used to simulate the actual granulation process of iron ore fines,and the iron ore fines granulation discrete element model and its evaluation system are constructed.The iron ore particle model with complex shape is constructed by the method of filling each other with circular particles,which can reproduce the iron ore particles of various shapes.The dimensionless number is used to simplify the granulating cylinder according to the similar principle for reduce the simulation work.The suitable JKR contact model was selected for the surface moisture content of the granulated iron ore fines,the mutual contact parameters and JKR model related parameters between the iron ore fines were obtained by measuring the repose angle of the cylinder.Through the simulation study of the different cylinder rotational speeds,the correlation between the cylinder rotation speed and the material motion state was studied.It was found that the optimum cylinder rotation speed was about 0.3 times of the critical speed of the cylinder;for the multi-mineral iron ore powder,the orthogonal test and uniform test design of different granulation proportioning schemes can reduce the test workload.In order to further analyze the particle distribution and mass distribution of the granulated products,the common vibrating screen is adopted.It is used to analyze the iron ore particle size distribution information,and a simplified model is constructed.The most suitable vibration parameters is selected as working parameters.The movement state of the granulation mixture in the cylinder was analyzed,which reflected the granulation performance of the granulation mixture.The granulation product sieving process was analyzed and the iron ore powder granules also were analyzed.The spatial distribution,combined with software post-processing functions and chart analysis,obtained the particle size distribution of iron ore fines and the mass distribution of the mixture.The simulation results show that,with the increase of iron ore powder B ratio,the amount of two iron ore fines entering the mixture+6.3mm is increasing,and the mass fraction of the granulated product in the+6.3mm fraction is gradually increasing.When the ratio of iron ore fines B reaches 70%,the amount of the two iron ore fines and the mass fraction of the granulated products reach a peak at the mixture+6.3 mm,and the corresponding granulation is also optimal.