Experimental Research On Fine Particle Removal By Multi-field Synergy Based On Core Of Bag

In recent years,with the rapid development of our economy and coal-based energy consumption structure,fine particle pollution is increasingly serious,which can not only cause haze weather to affect normal life and work,but also series of economic,social and ecological issues.However,conventional bag filter has low removal efficiency of fine particle,which cannot meet the dust emission standard.Therefore,it is considered to use multi-field synergy based on core of bag to achieve efficient removal of fine particles.Firstly,the efficient agglomeration and removal of particles of bag filters is studied in a wire-duct reactor under single field effect,including pulsed electric field and acoustic field.Penetration efficiency is utilized to characterize the agglomeration and removal effect.The results show that,at low initial concentration,under single field,pulsed electric field corresponds to the lowest penetration efficiency of fine particles,followed by acoustic field.And the larger the pulsed voltage,the higher the pulsed frequency,the lower the penetration efficiency.When the initial concentration of dust is 556 mg/m3,the efficiency of PM10 can reach to 99.45%and that of PM2.5 can reach to 99.21%with bag filter coupled with pulsed electric field.However,at high initial concentration,the penetration efficiency of bag filter coupled with acoustic field is higher than that of pulsed electric field,which cannot meet the dust emission standard.Secondly,the efficient agglomeration and removal of fine particles is studied under the effect of bag filter simultaneously coupled with acoustic filed,DC electric field and pulsed electric field.With negative DC corona discharge as pre-collection in the front and pulsed corona discharge as electric agglomeration in the middle and bag filter as collection in the behind,the penetration efficiency is increasing with the DC voltage,the pulsed voltage and the pulsed frequency.The penetration efficiency of multi-field synergy based on core of bag combined with pulsed electric field and acoustic field is much higher than that of single field either electric or acoustric.The influence of sound pressure level(SPL)and acoustic frequency becomes more complicated in the combined fields.There exists an optimal frequency and SPL for a given discharge voltage,and the optimal frequency and SPL will change with the voltage changes.Based on the experimental study,a highly efficient agglomeration and removal system of fine particles depending on bag filter is designed.The system consists of four areas namely negative DC corona discharge pre-collection area,acoustic agglomeration area,pulsed corona discharge electric agglomeration area,core of bag collection area.It can achieve a high removal efficiency of both total mass concentration of particulate matter and number concentration of fine particle.The system is easy for upgrading in existing bag precipitator equipment with a wide application prospect.