Influence of Ore Stage Flow Law of High-deep Chute on Chute Production
Chute is a common form of deposit development.With the increasing exploitation of alpine and deep resources,high-deep chutes are widely used because of its advantages of simple development methods,convenient transportation and low operating costs.Based on the long-term observation of the production practice of single-segment vertical high-deep chutes,we summarized the flow law of ore in high-deep chute,and put forward that the vertical full-section stage flow is a unique engineering phenomenon of high-deep chute which is different from short chute.Through analysis and research,it is found that there are limitations in the study of ore flow law in high-deep chute by numerical simulation and laboratory model test.Therefore,we adopted the research method of'practical understanding+theoretical analysis',and based on the research carried out by Sun Qicheng et al.of Tsinghua University,the cutting-edge results of the theory of riding chain and arching effect was used to explain the arching mechanism of ore granular in the chute.At the same time,combined with the analysis of gas-solid two-phase flow in the wellbore,the ore flow law of high-deep chute was studied.The causes of the staged flow characteristics of high-deep chute were analyzed,and the influence of the staged flow of high-deep chute on the common stagnation,blockage,wear and spalling phenomena in the production process of chute and the mixing and classification of ore in the chute was revealed.The influence of air flow in the chute on the granular flow was analyzed.On the one hand,the existence of flowing gas in the normal ore drawing process is beneficial to the ore flow and the destruction of the temporary balance arch.On the other hand,the drag force of gas produces the phenomenon of block and powder classification concentration,which promotes the stagnation and blockage of ore in the wellbore.It is proposed that the grain composition,density,water content,cohesiveness of the ore,the diameter of the chute and the roughness of the shaft wall are the basic factors causing the stagnation and blockage of the chute.The flow characteristics of the vertical full-section stage ore are the important reasons for the stagnation and blockage of the high-deep chute.The results open up ideas for the research and the safe and efficient production of high-deep chutes,and can provide reference for the design and use of high-deep chutes.
NETL
NSTL
万方数据
