箱式格栅除铁器有限元分析及在奶粉生产中的应用

Finite element analysis of box grid magnetic iron-separator and its application in milk powder production

目的:将箱式格栅除铁器应用在奶粉生产中.方法:在完全模拟奶粉工厂真实生产条件下,基于有限元仿真分析,探究除铁器的有效工作原理,进而通过单因素试验及矩阵分析,探究物料的下落高度、金属异物种类、场强强度、磁棒净距对箱式格栅除铁器有效拦截率的影响及优选设计方案.结果:假设最低可接受标准为对铸铁、304不锈钢、316不锈钢有效拦截率≥80%,则临界设计条件为:(1)当磁棒强磁环场强为1.0T时,下落高度≤100mm,磁棒层数≥6层,净距25 mm.(2)当磁棒强磁环场强为1.4T时,如物料下落高度≤100mm,则磁棒层数≥4层,净距25mm;如100m<物料下落高度≤300mm,则磁棒层数≥6层,净距25mm.结论:该研究成果可应用于奶粉及其他粉末状食品物料,如蛋白类原料、粉末油脂、淀粉、食品添加剂等.

Objective:The optimal design scheme of box grid magnetic iron-separator in milk powder production process was explored.Methods:In this study,the working principle of the box grid magnetic iron-separator was explored by using the finite element simulation analysis method under real production conditions in a fully simulated milk powder plant.Through the single factor test,the effects of material drop height,the type of metal foreign matter,the field strength,and the net distance of the magnetic bar on the effective interception rate of the box grid magnetic iron-separator were explored,and the design solution was optimized by using matrix analysis.Results:Assuming that the minimum acceptable standard is an effective interception rate greater than 80%for cast iron,304 stainless steel and 316 stainless steel,the critical design conditions are as follows:(1)When the magnetic field strength of the magnetic bar is 1.0 T,the drop height should be less than 100 mm,the number of layers of the magnetic bar should be greater than or equal to 6,and the clearance of the bar magnet is 25 mm.(2)When the magnetic field strength of the magnetic bar is 1.4 T,if the falling height of the material is less than 100 mm,the number of layers of the magnetic bar should be greater than or equal to 4,and the clearance of the bar magnet is 25 mm;If the falling height of the material is between 100 and 300 mm,then the number of magnetic rod layers should be greater than 6,and the clearance of the bar magnet is 25 mm.Conclusion:The research results have industrial application value for milk powder and other powdered food materials,such as protein-based raw materials,powdered fats and oils,starch,food additives,etc.