Experimental Study On Separation Performance Of Three-phase Cyclone In Underground Coal Mine

The limited space and large treatment capacity requirement during the treatment of mine water with coarse particles in underground coal mine always cause sediment silting in the ditch,the sedimentation tank and the sump.In order to solve the problem,a new type of gas-liquid-solid three-phase cyclone separator using high pressure gas as power source was proposed in this paper.By using the "Venturi effect",the underground high-pressure gas can suck mine water into the three-phase cyclone separator,and after separation,the separated gas can be discharged into the roadway,solids can be transported outside directly by using the conveyor belt and the treated mine water can be directly discharged into the sump.In situ separation of mine water can reduce the difficulty of cleaning the sump,increase the effective volume of the sump and improve the safety factor of coal mine production.Using RSM and Mixture model,the paper studied the numerical simulation for the designed?100-75 mm three-phase cyclone separator and analyzed the distribution law of the static pressure,the velocity and the particle motion inside the three-phase cyclone separator.The results show that with the increase of the gas velocity,the pressure drop,the axial velocity and tangential velocity of the fluid increase.With the increase of the exhaust pipe diameter,the pressure drop decreases first and then increases.When the exhaust pipe diameter is 20mm,the axial and tangential velocities reach the maximum.The change of exhaust pipe insertion depth has no obvious effect on the velocity field,and the pressure drop decreases first and then increases.With the increase of the apex diameter,the pressure drop is basically unchanged,while the axial velocity and tangential velocity decrease.With the increase of material concentration,the pressure drops increases while the axial and tangential velocities decrease.Particle trajectory analysis shows that when the exhaust pipe diameter is 20mm and the exhaust insertion depth is 60mm,the 5?m and 10?m particles have shorter trajectories,shorter separation time and better separation effect in the separator.Besides,the influence of various parameters on the degassing rate and solid-phase separation efficiency of the first segment of the three-phase cyclone separator was investigated.The results show that the degassing rate and solid phase separation efficiency increase with the increase of gas velocity.As the exhaust pipe diameter increases,the degassing rate decreases,and the solid-phase separation efficiency increases first and then decreases.As the exhaust pipe insertion depth increases,the degassing rate increases first and then decreases,and the solid-phase separation efficiency decreases.The degassing rate is not affected by the apex diameter.The degassing rate of a separator increases with the increase of material concentration.On the basis of the simulation analysis,the test rig was built and the separation performance test of the three-phase cyclone separator was carried out.The pressure drops,the degassing rate of the first segment of the separator,the solid concentration of underflow and the overflow the solid separation efficiency were used as the evaluation indexes.The effects of different operating parameters and structural parameters on the separation performance of the ?100-75mm three-phase cyclone separator were studied,including the gas velocity,the exhaust pipe diameter,the exhaust pipe insertion depth and the apex diameter.The test results were consistent with the numerical simulation results,and the optimal parameter combination was obtained as follows:the gas velocity is 12m/s,the exhaust pipe diameter is 20mm,the exhaust pipe insertion depth is 60mm,the apex diameter is 5mm.The verification test shows that the solid phase concentration of the underflow is 62%,and the solid phase separation efficiency is 82%.By means of numerical simulation and experimental research,the study systematically analyzed the influence of structural parameters and operating parameters on the separation performance of the new three-phase cyclone separator,which has certain theoretical guiding significance for the research and development of the efficient three-phase cyclone separation equipment.The designed three-phase cyclone separator has the advantages of compact structure,low energy consumption,large processing capacity and high separation efficiency,which is especially suitable for the limited underground space and has important engineering application value.