Numerical Simulation Of PM2.5 Electrostatic Dust Removal Process Under Multiple Coupling Effects

Electrostatic precipitator has the characteristics of high dust removal efficiency,less maintenance and wide application range.It is precisely because of these reasons that electrostatic precipitator has been widely applied in each dust removal stage of industrial production.For large dust particles,the dust removal efficiency of traditional electrostatic precipitator can reach almost 100%.However,for dust particles with particle size below 10μm,the dust removal efficiency is still very low,especially for the removal effect of PM2.5 is not ideal.Therefore,the research of new electrostatic precipitator and fine dust purification has attracted the attention of scientists all over the world.In this paper,line-plate electrostatic precipitator is taken as the research object.For PM2.5,finite element simulation software Comsolmultiphysics is used to conduct multi-field coupling of flow field,electric field and sound field to simulate the dust removal process.To explore the dust removal rule of PM2.5,a new idea of adding sound waves to the front end of electrostatic precipitator to promote particle agglomeration to improve the dust removal efficiency of electrostatic precipitator was proposed,and the influence of sound pressure level,sound wave frequency and other factors on the dust removal efficiency of linear plate electrostatic precipitator after adding sound waves was explored.The research results can provide some theoretical guidance for the optimization and design of line-plate electrostatic precipitator,and put forward a feasible scheme for practical industrial production.The electric field in the wire-plate electrostatic precipitator was simulated.The electric field and the flow field were coupled to simulate the dust removal of particles with different particle sizes.When the particle size is larger than 1μm,the larger the particle size,the earlier the dust collection,the larger the migration range,the faster the dust collection,the better the dust collection effect.When the particle size is sub-micron,the dust removal efficiency of 0.6μm particle size is the lowest,which is caused by the decrease of particle electromobility caused by diffusion charge and the increase of particle electromobility caused by electric field charge.All the above factors are caused by the gradual increase of dust particle size.In addition,the two factors will exist simultaneously and have an effect,so that the dust particle size is the weakest around 0.6μm,which is also the reason for the low dust removal efficiency of PM2.5.Different voltages and flow velocities were selected to simulate the dust removal process.The results showed that the dust removal efficiency increased with the increase of voltage and increased with the decrease of inlet velocity.In order to solve the problem of low PM2.5 dust removal efficiency,sound waves are added to the front entrance of the online plate-type electrostatic precipitator,and sound field is introduced in the original dust removal process to simulate the dust removal process.The results show that electrostatic precipitator can improve the dust removal efficiency of PM2.5 after adding sound field.Sound pressure level and sound frequency are two important factors affecting dust removal efficiency.The influence of sound pressure level on dust removal efficiency is linear.The higher the sound pressure level is,the higher the dust removal efficiency will be.Acoustic frequency does not change the influence of sound pressure level on dust removal efficiency.The higher the sound pressure level is under different acoustic frequencies,the higher the dust removal efficiency will be.There is no simple linear relationship between acoustic frequency and dust removal efficiency,and there is an optimal dust removal acoustic frequency of 1300Hz-1400 Hz.