Research On Improving The Screening Efficiency Of Hammer Mill

Crushing is one of the important processes in feed processing.The effect of crushing affects the cost and quality of feed processing.The hammer mill is one of the important equipments for feed crushing.The traditional hammer blade crusher has a material circulation layer,which causes prominent problems such as high crushing energy consumption,low screening efficiency,high noise,over-crushed materials,fast feed temperature rise,and hammer and sieve wear.The research team has developed a new type of hammer blade crusher,which effectively destroys the circulation layer,but there are also problems such as the mismatch between the separation efficiency and the crushing efficiency,and the serious accumulation of materials in the return pipe.In order to solve this defect and improve the working efficiency of the new hammer mill,this study uses a combination of computer simulation and experiment to analyze the relationship between the material separation characteristics of the new mill and its influencing factors.Carried out research in the following areas:(1)Simplify the crusher model,and then use EDEM and ANSYS-Fluent numerical simulation software to analyze the gas-solid two-phase flow of the crusher,and conduct a screening experiment on the existing crusher.By comparing the particles in the crusher in the experiment The movement and particle movement in the simulation,the particle size distribution of the crushed particles after the experiment and the particle size distribution in the numerical simulation,as well as the screening efficiency after the experiment and the screening efficiency of the simulation results verified the DEM-CFD coupling calculation crusher sieve The feasibility of sub-efficiency.(2)Based on the DEM-CFD coupling,the crusher was numerically simulated,and the complete movement process of the particles in the crusher was obtained,and the movement law of the particles was found;the velocity and pressure distribution clouds of the fluid phase in the crusher were obtained,and found The velocity and pressure distribution of the fluid phase in the pulverizer were studied;the effects of different feeding rates,feeding amounts and the diameter of the return pipe on the pulverizer screening efficiency were studied,and the pulverizer was screened under different working conditions.The efficiency and the speed of particle movement,the number of collisions and the amount of material output change with time.(3)Based on the Central Composite functional design test plan in the data analysis software Design-Expert,the response surface analysis of the sieving efficiency of the pulverizer is carried out,and the three factors and factors and factors of the return tube diameter,feeding rate and feeding amount are studied.The interaction between them affects the screening efficiency of the crusher,the regression equation of the influencing factors and the screening efficiency is established,and the optimal solution of the objective function is found.In this study,through the combination of computer simulation and experiment,the relationship between the material separation characteristics of the new crusher and its influencing factors was studied,which provided a theoretical basis for its optimal design and application.