Study Of The Crushing Characteristics And Energy Consumption Of Several Rock-like Materials

The grinding operation is a process in which the size of the mineral rock is changed from large to small and then to fine,and is also a process of continuous energy consumption.The key factor affecting energy consumption is the initial particle size.The study of the crushing characteristics and energy consumption of mineral rocks at different particle sizes is of great significance to the analysis of the crushing mechanism of mineral rocks,and can also provide important theoretical support for the optimisation of the crushing and grinding processes of enterprises.Based on the differences in impact resistance and grinding resistance between different Mineral rocks,this thesis selects Limonite,Hematite and Tremolite that have not been broken and ground after blasting in the quarry as the research objects,and conducts drop weight tests and ball milling tests under different particle sizes respectively,the main research work is as follows:A systematic study of the differences in the crushing characteristics of three mineral rocks at different particle sizes.In the drop weight test,the fracture density of small size Limonite and Hematite particles is much smaller than the fracture density of large size particles,and as the damage decreases with decreasing size,large size particles are easier to achieve crushing,and Tremolite increases with decreasing size,and small size particles are easier to achieve crushing;in the ball mill test,Limonite and Tremolite particles become higher with decreasing size under the screen,and Hematite is the first to become lower and higher with decreasing size under the screen,but all show that small size particles are easier to achieve ball mill crushing.The relationship between product fineness and Mineral rock size is analysed in depth.In the drop weight test,the smaller the Mineral rock particle size,the more fine-grained product is obtained,but in the ball mill test,the smaller the Mineral rock particle size,the less fine-grained product is obtained.The relationship between product fineness and crushing energy consumption is explored,with the fineness characteristic value t₁₀ increasing as the specific energy increases,showing a positive relationship between specific energy and crushing fineness.Fitting a crushing energy model to three mineral rocks,obtained by the amount of resistance to impact crushing:Hematite>Limonite>Tremolite,lithology in the"soft"range under the drop weight impact test,resistance to ball mill crushing:Hematite>Limonite>Tremolite,lithology of Limonite and Hematite in the"extrahard"range under the ball mill test,Tremolite in the"chinasoft"range under the ball mill test.Using the fineness characteristic values to establish the correlation between impact crushing and ball mill crushing,it is found that for the same specific energy,impact crushing fineness characteristic value t₁₀ is 1.5 to 3 times higher than ball mill crushing fineness characteristic value t₁₀.Considering the crushing and grinding as a whole process,it is obtained that the Mineral rock in the-31.5+13.2 mm particle size range is most conducive to crushing and grinding and consumes the least amount of energy.Analysis of the actual breakage and grinding energy consumption of the beneficiation plant,found that the difference in energy consumption between breakage and grinding is about4 times,the feed size is the most important factor affecting the energy consumption of crushing and grinding,and proposes to replace breakage with explosion,more crushing and less grinding,in order to achieve an overall reduction in energy consumption.