Experimental Study On The Removal Of Fine Particles By The Technology Of Electrostatic Charging,atomization And Ultra-gravity

In recent years,with the continuous development of human society and technology,the process of industrialization has been accelerating.Then the problem of atmospheric environmental pollution has become more serious.The fine particles(PM_2.5)emitted by industrial activities has the advantages of high concentration and great controllability.This part of the fine particles can be effectively controlled to improve air quality.The Cloud-Air-Purifying?CAP?dust removal technology combines atomization and ultra-gravity.It has much advantages,such as low investment,small land occupation,low energy consumption and stable performance.Meanwhile,it can efficiently collect fine particles with low cost.However,in order to meet the increasingly strict environmental quality standards,it is necessary to optimize the technology and achieve the effect of efficiently removing PM_2.5.Therefore,this paper proposes a technology which combines the charging technology and the atomized ultra-gravity dust-removing technology.The new technology can use the electrostatic force between the particles and the droplets to make the particles grow up.This agglomeration process is very efficient,so that fine particles can be removed.Firstly,the experimental platform of combined charging,atomization and super-gravity dust removal technology is established.The molecular sieves and talcum powder particles has small size,and they are commonly seen in the industry.In this experiment,we choose these two kinds particles to study its collection efficiency by the dust removal technology.A corona electric field is arranged in the system.After the droplet flow passes through the electric field region,droplets will carry charges,and then collides and agglomerates when contacted with the particles.Then the fine particle size increases,and is efficiently removed in the cyclone.The experimental results show that the dust removal system can remove particles efficiently and improve the collection efficiency of PM_2.5 significantly?the collection efficiency of molecular sieve particles is 90.64%,the collection efficiency of talcum particles is 98.66%?.It is because after charging,the electrostatic force between the particles and the droplets strengthens the collision agglomeration between them.It can increase fine particles size,thereby improving the collection efficiency of the dust particles.In addition,by analyzing the dust samples after the experiment,the particle size distribution and the SEM image indicate that the coagulation agglomeration is significantly enhanced after charging.Secondly,in order to explore the influence of the charging conditions on the dust collection efficiency of the system.The charging schemas and the charging effect have been studied.The particles collection efficiency under the conditions of charging particles only,charging both of particles and droplets with opposite polarities.In addition,various electrolytes are mixed in the system.The experimental results show that charging particles and droplets with opposite polarities can further improve the collection efficiency of dust particles?the collection efficiency of molecular sieve particles is 92.57%,the collection efficiency of talcum particles is 99.10%?.At this time,the electrostatic force between the droplets and the particles is stronger,and the agglomeration is more sufficient.Furthermore,the addition of the strong electrolyte in water helps improve the collection efficiency,while the weak electrolyte will cause a negative effect for removing the particles.When the concentration of the weak electrolyte becomes bigger,the collection efficiency of the particles is inhibited more.Finally,the effect of atomization and super-gravity conditions on the collection efficiency of the dust remove system is investigated.As the inlet flow rate increases,the removal efficiency of the dust removal system gradually increases,but its growth rate gradually decreases.However,increasing the inlet flow rate will increase the pressure drop in the cyclone and then increase the system energy consumption.Changing the vapor concentration can also significantly change the collection efficiency of dust particles.As the vapor concentration increases,the collection efficiency of dust particle firstly rises and then tends to be gentle,which means that the amount of droplets required for particle growth has reached saturation.The collection efficiency of the system cannot be further improved.In summary,the new dust removal technology can significantly improve the removal efficiency of dust particles,especially for PM_2.5.By studying the operating parameters of the system,it is found that by changing the charging condition,the atomization condition and the ultra-gravity condition can affect the collection efficiency of the dust particles.Therefore,the study of its operating parameters helps to further optimize the charged-atomized ultra-gravity dust removal.Then it will play a greater industrial application value to improve air quality.