基于有限元-离散元耦合矿石强度在微波照射下变化规律研究

Study on Variation of Ore Strength under Microwave Irradiation Based on Finite Element and Discrete Element Coupling Method

针对以往研究中有限元无法模拟裂纹开展以及离散元无法考虑试块中微波不均匀性的问题,采用有限元-离散元耦合方法模拟微波弱化矿物的过程,监测模型中强度、温度、裂纹变化情况,根据强度变化分析黄铁矿粒径、含量及微波功率对强度弱化效果的影响。结果显示,微波可以有效降低矿物强度;黄铁矿粒径、含量对微波弱化矿物效果的影响不大,微波功率对弱化效果有着重要影响;矿物强度降低主要发生在一段时间内。结果表明:有限元-离散元耦合方法可以更加准确地描述微波辅助矿物解离情况;微波辅助矿物解离可以用于含不同粒径、不同含量黄铁矿的矿物解离,提高微波功率、选择合适的照射时间可以有效提高能量利用效率。

A coupling method of finite element and discrete element was used to simulate the process of microwave weakening minerals for dealing with the problem that the finite element method can not simulate the cracking process and the discrete element method can not consider the nonuniformity of microwave in the sample.The changes of strength,temperature and cracking process in the sample were monitored,and the influence of the particle size of pyrite,the content of pyrite and microwave power on microwave weakening effect were analyzed based on the change of strength.The results show that microwave can effectively reduce the strength of minerals,the particle size and the content of pyrite have little effect on the effect of microwave weakening minerals,and microwave power has an important effect on the weakening effect.The decrease of mineral strength mainly occured in a certain period of time.The results show that the coupling method of finite element and discrete element can simulate microwave-assisted mineral dissociation more accurately,and it is feasible to use this method to study microwave-assisted mineral dissociation.Microwave assisted mineral dissociation can be used to dissociate minerals with different particle sizes and different contents of pyrite.Increasing microwave power and selecting appropriate irradiation time can effectively improve energy utilization efficiency.