Research And Development Of Divider And Milling Equipment In Coal Preparation Process

China is the biggest country of coal consumption.Even though the new energy(wind and solar energy)has been promoted to some extent,coal will play an important role in energy consumption field in the future due to the restrictions of cost and technology.However,it will produce pollution such as sulfur dioxide and dust and reduce air quality with the use of some inferior coal.Therefore,it is significant to rapidly obtain the coal sample that can be used for testing and control the use of inferior coal to reduce the environmental pollution.The automatic coal sample preparation system can improve the efficiency and reduce the intensity of labor.In this thesis,the divider and grinding equipment in the system are deeply researched by combining simulation and experiment.The details are as follows:Firstly,the structure of an adjustable divider is designed and the 3D model of proposed scheme has been established according to its function and requirements.Then the preliminary verification of the rationality and feasibility of the designed structure is completed based on the discrete element simulation software.Secondly,a vertical vibration mill that can feed and discharge automatically is designed and the equivalent mechanical model of its transverse motion is established.Subsequently,the formula for calculating the transverse movement path is obtained through theoretical analysis of vibration body.Then the parameterized model of vertical vibration mill is established with the help of multi-body dynamics software.Besides,the simulation analysis of the vibration body and the force between grinding media is carried out,which provides the basis for the parameter optimization of vertical vibration mill.Again,in order to obtain the best pulverization effect,a multi-objective optimization model is set up with using structure parameters of vibration mill,and its objectives are vibration intensity,contact force and volume of grinding media.Then the response surface approximate model of vertical vibration mill is built by combining experimental design and approximate model.And an optimization on the above model is carried out by multi-optimization genetic algorithm,then the Pareto optimal solution sets are obtained,which provide a reference for designers to choose reasonable parameters.Finally,the rationality of designed structure and the accuracy of division ratio are verified by the prototype experiment of divider,and the grinding experiment of vibration mill also proves the effectiveness of the optimization design and it also has a good self-cleaning performance.