The Study On Erosion Mechanism Of Cyclone Separator For Gas Purification

In order to investigate the wall erosion of cyclone separator used in natural gas transportation,the gas-solid two-phase flow in high-pressure axial cyclone separator was simulated by numerical simulation method.The simulation results revealed that the erosion mechanism and effect factors of erosion of cyclone separator.Furthermore,some srtructure optimization methods of cyclone separator were proposed to restrain the erosion.Firstly,a 150 mm axial cyclone separator was used to investigate the performance under different operation conditions.The results showed that the tangential velocity of the cyclone separator increased with the increasing of operating pressures and inlet velocity.Higher operating pressures were beneficial to improve the separation efficiency of the separator.Secondly,the erosion model in Fluent was used to study the erosion of the axial cyclone separator.The simulation results showed that the erosion mainly occurred at the bottom of the cone of the cyclone,and the erosion belts were spirally distributed.The erosion rate was proportional to 2 to 3 powers of the velocity,and which also had an approximate linear relation with particle concentration.With the increasing of operating pressure,the entrainment effect of airflow on particles increased,and the erosion rate at the lower part of cone increased obviously.The wall erosion caused by small particles mainly located in the lower part of the cone,while large particles could easily cause the erosion at the junction between cylinder and cone.Based on the study of the flow field and the erosion proposed measures to reduce the erosion of the cyclone cyclone,the results showed that to increase of the diameter of the dust exit,or the length of the cone,to install reflow cone device or a slit design could all effectively reduce the erosion on the surface,which provided insights for the wear resistance of the cyclone separator.Expanding the diameter of the dust exit from50 mm to 65 mm and 80 mm,the maximum erosion rate of the cone reduced 42.85%and 65.14%.Increasing the length of the cone increased from 270 mm to 300 mm and324 mm,the maximum erosion rate of the cone reduced 27.43% and 40.57%.However,the increase of the diameter and the length could led to an efficiency reduction.The maximum erosion rate of the cyclone which vortex finder with a reflow cone reduced only 2.86%.It showed little effect on reducing the erosion.With the design of the slit on vortex finder,the maximum erosion rate of the cyclone cone reduced above 80%,which could significantly reduce the erosion of particles on the cone and improve the separation efficiency.Therefore,the improvement of the structure of the vortex finder was an effective method to reduce erosion.