| China's iron ore reserves are abundant,but they are generally of low grade,uneven distribution,and difficult to mine,which cannot meet the needs of China's iron and steel production,under the condition of large iron ore demand and low output,mining,and sorting of ore work have brought huge challenges;especially in recent years,China's requirements for ecological and environmental protection have become higher and higher,the traditional wet separation process has such problems as the tailings pond occupies a lot of lands,wastes water resources,high production costs,and brings serious pollution to production and life and potential safety hazards,with a series of problems,there is no way to meet the current development needs.In the inland areas of China's north-west,perennial drought,cold weather,water resources are relatively scarce,and iron ore stone there is "poor,small,miscellaneous" features,from a variety of considerations,dry sorting more suitable for cold arid regions but dry sorting there are still many problems to be solved in common,therefore,for the dry separation efficiency increase of research has important practical significance.In this paper,based on the new three-stage dry permanent magnetic separator developed by the research group,the multi-physical field coupling software COMSOL Multiphysics is used to analyze some factors affecting the sorting grade,and the movement law of mineral particles is obtained,the separation effect of mineral particles is numerically simulated and verified by experiments,so as to seek the factor level combination under the best working condition of the new magnetic separator,so as to improve the economic benefit.COMSOL is used to analyze the magnetic field characteristics of the magnetic roller,observe the distribution of the magnetic flux density streamline,and make full use of the magnetic field potential in the separation chamber,which is conducive to the separation of magnetic mineral particles;the new dry magnetic separator introduces the wind factor,which forms a gas-solid two-phase flow with the mineral particles in the separation chamber,simulates the movement of mineral particles in the separation chamber,summarizes its movement law,and improves the flow efficiency,high speed air can improve the loose degree of materials,make the peripheral magnetic particles get more separation opportunities,improve the separation grade;simulate the separation results of magnetic separator under different factors and levels,with the concentrate grade,m Fe recovery,concentrate yield and other indicators as reference,the best working parameters are obtained: wind speed 25 m / s,rotating speed 115 r / min,material layer thickness 30 mm,feed particle size-1mm.In order to verify the accuracy of the numerical simulation results,a magnetic separation test platform was established based on the prototype of a new three-stage dry permanent magnet cylinder magnetic separator,on this basis,several groups of magnetic separation tests were carried out to seek the best separation parameters.The first is the orthogonal test,through which the influence of feed particle size,wind speed and Material layer thickness on the concentrate grade can be obtained,and the primary and secondary relationship of various factors affecting the concentrate grade is determined,combined with the influencing factors and levels,the best factor level combination can be obtained as(A3B3C3);through single factor test on different levels of various factors,the best working condition can be obtained as follows the results show that: the wind speed is 25 m / s,the rotational speed is 115 r / min,the material layer thickness is 30 mm,and the feeding particle size is-1mm. |
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