Study On The Influence Of Ball Mill Speed And Grinding Ball Size On Efficiency And Energy Consumption

The ball mill is a device for re-grinding broken materials.It is widely used in industrial sectors such as building materials,electric power,mineral processing,etc.,for dry or wet grinding of various ores and abrasives.In recent years,with the rapid development of China’s economy,the demand for grinding materials in infrastructure construction and industrial production is increasing.The ball mill belongs to large-scale high-energy-consuming equipment,and the state advocates "green,energy-saving and environmental protection".Put forward new requirements for ball mill grinding technology.Therefore,in order to improve efficiency and reduce energy consumption,it is necessary to study the effects of ball mill speed and grinding ball size on efficiency and energy consumption.Firstly,the mechanism of the ball mill is studied.The kinematics and dynamics analysis of the grinding body in the ball mill are carried out.The calculation formulas of the working parameters such as the rotational speed,loading,grading,impact kinetic energy and power of the ball mill are deduced to lay a theoretical foundation for the simulation parameter setting.The traditional driving method of the ball mill is three-phase asynchronous motor+reducer.In order to improve the transmission efficiency and reduce the energy consumption,it is replaced with a high-efficiency driving device permanent magnet direct drive motor,and the parameter calculation method is given,and the Ryukyu start method is designed according to the load characteristics.Based on the discrete element method,the ball mill crushing and grinding mechanism is analyzed.The cement plant ball mill is taken as an example for three-dimensional modeling and parameter calculation.The ball mill is combined with the actual working conditions and subject research of the material particle crushing and grinding process.The discrete element simulation analysis software EDEM was conducted secondary development of EDEM-API,Through the dynamic link library compiled by C++and Microsoft Visual Studio2008,the particle replacement and the number of names are called to complete the particle replacement,so that the large material particles are bonded by a plurality of small material particles by the bonding force of the normal stress and the shear stress.Under the impact and grinding with the grinding medium,the large material particles are decomposed into small material particles to simulate the ball mill crushing process.According to the theoretical calculation value of the parameters,the EDEM software is used to set different speed values of the ball mill,and the steel ball grading curve is combined to simulate different diameters of the grinding body to obtain the image of the number of bond breaks and torque,and the actual working conditions and simulation are combined with the design efficiency and energy consumption evaluation indicators,and analysis and comparison.Considering efficiency and energy consumption and optimizing analysis,the optimal transfer rate 80%is obtained,and the influence of the size of the grinding body on the efficiency and energy consumption is analyzed.The scientific matching ratio is combined with the grading curve,and the impact kinetic energy of the large ball grinding ball is fully utilized and broken.Strong ability,strong ball grinding ability,strong contact with materials and low power consumption,and simulation analysis of cement plant grading adjustment,improved efficiency after adjustment,reduced power consumption;From the perspective of reducing energy consumption,the lightweight abrasive ceramic ball is applied to the ball mill.The density of the ceramic ball is smaller than that of the steel ball,which can reduce the power consumption.Through theoretical and simulation analysis of the steel ball and the ceramic ball,the crushing and grinding efficiency is also reduced.Therefore,the characteristics comparison and power saving calculation of steel ball and ceramic ball,appropriate increase of ceramic ball filling rate can reduce the impact on crushing and grinding efficiency,the ceramic ball is applied to Shandong Zhonglian Cement Factory and combined with theoretical analysis to determine the best filling rate 37%.To reduce energy consumption while reducing the impact on production efficiency.Studying the effects of ball mill speed and grinding ball size on efficiency and energy consumption,we can use relevant conclusions to better guide production practices,thus achieving the goal of improving efficiency and reducing energy consumption.