Research And Development Of A Spiral Stirred Mill Considering The Size And Distribution Width Of Sepiolite Powder

With the increasing development of our country's grinding industry,non-metallic mineral powder is widely used in industry,agriculture,construction and other fields.As a common non-metallic ore,the ground sepiolite powder has become an indispensable raw material for many industries due to its good adsorption and catalytic properties.The stirred mill was often used for grinding to obtain ultra-fine sepiolite ore powder.In the grinding equipment,the vertical stirred mill is widely used because of its simple structure,high grinding efficiency and convenient operation.In the grinding equipment,a vertical stirred mill is widely used because of its simple structure,high grinding efficiency and convenient operation.How to reduce the particle size and distribution width of the ore powder after grinding,and improve the quality of the ore powder has become a hot topic for domestic and foreign scholars.Since sepiolite is a non-metallic clay mineral,agglomerates are prone to occur when the particle size reaches the micron level during the grinding process,which affects the further reduction of the particle size of the mineral powder and ultimately affects the grinding efficiency.In order to effectively solve the above problems,this paper mainly does the following research.(1)The physical parameters and mechanical properties of sepiolite are tested.The physical parameters mainly include density,hardness and Poisson's ratio,and the mechanical properties include static compressive strength and tensile strength,as well as dynamic compressive strength and elastic modulus.The density is 2076.3kg/m3,the hardness is 21.15 HRM,the poisson's ratio is 0.2,the elastic modulus is1093.12 MPa,the static compressive strength and tensile strength are 13.11 MPa and6.57 MPa,respectively,and the dynamic compressive strength is 20.06 MPa.The modulus of elasticity is 3689.04 MPa.(2)Analysis of the pulverization mechanism and mill design of the spiral stirred mill.Aiming at the agglomeration of sepiolite ore during the grinding process and reducing the particle size and distribution width of the sepiolite ore powder after grinding,analyzed the crushing mechanism of the spiral stirring mill,and developed a brand-new spiral stirred mill based on the theory of lamination crushing.(3)The particle bonded model(BPM)in the Discrete Element Method(DEM)is used to simulate the grinding process of sepiolite ore in a spiral stirred mill.The speed of the media ball,the number of collisions,and the rotational kinetic energy are used to characterize the grinding effect of the spiral stirred mill.The energy consumption of the media ball and the wear of the mill are used as evaluation indicators to influence the important process parameters(mill speed,media ball size)for grinding simulation to obtain the optimal process parameters.(4)The sepiolite ore grinding experiment was carried out with the developed laboratory-scale spiral stirred mill to verify the rationality and accuracy of the design and simulation.The grinding process of sepiolite ore in a spiral stirred mill is studied by a combination of numerical simulation and experiment.The results show that the developed spiral stirred mill can effectively reduce the size and distribution width of sepiolite powder after crushing,and it is not easy to produce the agglomeration of ore powder.The optimal process parameters of the spiral stirred mill are obtained through simulation and experiment.