Research On Underground Pretreatment Technology Of Mine Water

After the mine water containing coal slime particles is collected in the water sump,a large amount of coal slime particles is deposited in the water tank.On the one hand,the effective volume of the water tank is reduced,and the water storage capacity of the water sump is reduced,the risk of mine flooding is increased;on the other hand,it shortens the clearance period of water sump,increases the clearance workload of water sump,and reduces the production efficiency of coal mine enterprises.Therefore,pretreatment of mine water before it enters the water sump can greatly reduce the deposition of suspended solid particles such as coal slime in the water sump.It has important social significance for improving the production safety of enterprises,prolonging the clearance period of water sump,reducing the labor intensity of workers,and improving production efficiency.The underground pretreatment system for mine water researched in this topic mainly includes two parts.In the first part,the rectangular sedimentation tank and the rope traction reciprocating scraper were used to remove the coarse coal slime particles in the mine water.In the second part,the hydrocyclone group was used to remove the fine slime particles in the overflow mine water of the rectangular sedimentation tank.After analyzing the basic structure of the rectangular sedimentation tank,the basic structure size of the underground rectangular sedimentation tank was determined.In order to study the influence of inlet velocity on the sedimentation effect of coal slime particles,the flow field in the sedimentation tank was simulated,the simulation results showed that the sedimentation efficiency of coal slime particles decreased with the increase of the inlet velocity.In order to verify the simulation data,the model of rectangular sedimentation tank was built and related experiments were conducted.The sedimentation efficiency obtained by the experiments were lower than that under the simulation,but the change trends of the two were consistent.In order to study the influence of the length of the rectangular sedimentation tank and the initial coal slime volume fraction at inlet on the sedimentation effect of the coal slime particles,the flow field in the sedimentation tank was simulated.The simulation results showed that when the ratio of the length to the effective depth of the rectangular sedimentation tank was 14,the sedimentation efficiency of the coarse coal slime particles in the sedimentation tank could reach 90%,most of the coarse coal slime particles could be removed.As the initial coal slime volume fraction at inlet increased,the sedimentation efficiency of the coal slime particles in the sedimentation tank decreased,and the decrease rate of sedimentation efficiency of coal slime particles in the sedimentation tank gradually decreased with the increase of initial coal slime volume fraction.The basic structure and statics of the rope traction reciprocating scraper were analyzed.In order to study the influence of the position and height of the scraper bar on the sedimentation effect of the coal slime particles in the sedimentation tank,the flow field in the sedimentation tank was simulated.Through simulation analysis,the sedimentation of coal slime particles at different positions and heights of the scraper bar were obtained.On the basis of improving the sedimentation efficiency of the coal slime particles,the appropriate position and height of the scraper bar were determined.Using the cyclone separation effect of the hydrocyclone,the separation efficiency of the coal slime particles with a particle size of 20 ?m could reach 70%,which can realize the separation and removal of most fine coal slime particles,and reduce the amount of subsequent suspended particles deposited in the water sump.In order to study the influence of coal slime density,inlet velocity and inlet pipe shape of hydrocyclone on the separation performance of hydrocyclone,the flow field in the hydrocyclone was simulated,through simulation analysis,it was found that the greater the density of the coal slime,the better the separation effect.Increasing the inlet velocity of the hydrocyclone was conducive to improving the separation efficiency of the coal slime particles,And the growth rate of separation efficiency was related to the particle size.The use of tapered inflow tube was conducive to improving the efficiency of cyclone separation of coal slime particles in mine water.From the perspective of the difficulty in clearance and the short clearance period of underground water sump,this paper has described in detail the technical scheme for the underground pretreatment of the mine water.By studying the underground pretreatment system of the mine water,Increasing the pretreatment efficiency of underground mine water can reduce the clearance workload of water sump,which has certain practical significance for improving the economic benefits of enterprises and society.