基于EDEM的废菌棒粉碎分离机设计与试验

Design and test of waste bacteria stick crushing separator based on EDEM

为改变废菌棒人工脱袋、机械粉碎的低效率模式,设计一台集脱袋、粉碎一体的小型粉碎分离机。对脱袋装置和粉碎装置进行设计,分析粉碎过程中绞龙对废菌棒的作用力。基于离散单元软件EDEM,建立废菌棒的bonding模型,并对粉碎过程进行仿真。通过设计正交试验,得到绞龙参数对废菌棒粉碎程度的影响并建立预测模型;通过响应面分析和预测模型对影响废菌棒粉碎程度的参数进行优化,得到最佳工作参数为:粉碎轴转速323.4 r/min,绞龙外径261.185 mm,叶片厚度6 mm,模型预测废菌棒的粉碎程度为81.739%。将最佳工作参数代入仿真试验,对比得到模型预测值与仿真值间的相对误差为1.79%,验证预测模型的可用性。以绞龙外径260 mm,叶片厚度6 mm制造样机,进行粉碎试验,结果表明:当绞龙转速为320 r/min时,整机工作性能稳定,废菌棒喂入顺畅,粉碎合格率为92%,菌袋脱净率为93%,满足废菌棒粉碎分离机设计需求。

In order to change the low efficiency mode of manual bag removal and mechanical crushing of waste bacteria rods,a small crushing separator integrating bag removal and crushing was designed.The de-bag device and the crushing device were designed,and the force of the auger on the waste bacteria rod during the crushing process was analyzed,based on the discrete element software EDEM,the binding model of the waste rod was established,and the grinding process was simulated.Through the design of orthogonal test,the influence of the parameters of the auger on the grinding degree of the waste rods was obtained and the prediction model was established.Through response surface analysis and prediction model,the parameters affecting the grinding degree of waste bacteria rods were optimized.The best working parameters were obtained as follows:the rotating speed of the grinding shaft was 323.4 r/min,the outer diameter of the auger was 261.185 mm,and the thickness of the blade was 6 mm.The model predicted that the grinding degree of waste bacteria rods was 81.739%.The best working parameters were substituted into the simulation test,and the relative error between the predicted value of the model and the simulated value was 1.79%,which verified the availability of the prediction model.The prototype was manufactured with the outer diameter of the auger of 260 mm and the thickness of the blade of 6 mm,and the crushing test was carried out.The results showed that when the rotation speed of the auger was 320 r/min,the working performance of the whole machine was stable,the feed of the waste bacteria rod was smooth,the crushing qualification rate was 92%,and the bacteria bag removal rate was 93%,which met the design requirements of the waste bacteria rod crushing separator.