Study On The Removal Performance Of Fine Particles By Electrocoagulation

In recent years,as relevant emission standards in China improves continually,it's difficult for ordinary dust removal equipments to meet the emission standards,the existing dust removal equipment needs further transformation,especially to improve the ability to capture fine particles.Compared with other technologies,there is no need to change the original dust removal equipment if electrocoagulation was applied.As electrocoagulation has other obvious technical advantages,it's suitable for industrial applications and it is a hot research spot.In this paper,the experiment and numerical simulation method were used to study the effect of dust coagulation and removal.By using the cement raw material dust and the electrostatic precipitator experimental platform as the research object,basic performance of the dust removal system was studied.The experimental study on the coagulation performance of the electrocoagulator was carried out by changing the working voltage combination of the electrocoagulator and the influence of the electric coagulator on the particle size of the dust particles and the total efficiency of the whole system was investigated.At the same time,the numerical simulation of the coagulation behavior of the internal coagulator was carried out by using the numerical simulation software COMSOL.The main conclusions are as follows:1.When the positive voltage of the electrocoagulator was +20k V,+25kV,+30kV and +35kV respectively,the ratio of the median particle size before and after the condensation of the dust particles increases with the increase of the negative voltage.And the ratio increased from 2.33 to 5.16 gradually.When the positive voltage was +40kV,the ratio of the median diameter of each negative voltage declined in different degrees.When the positive voltage was +35kV,the increase of the negative voltage would optimize the coagulation effect of dust particles.2.For the dust deposited at the bottom of the electrocoagulator,the median particle size of the dust particles is 88.37?m and the volume fraction of dust above 100?m is 44.23%.SEM images showed that in the same viewing angle range,when the condensed voltage is ±40kV,the number of particles is significantly less than that of ±20kV.At the same time,the size of dust particles at ±40kV is significantly larger than that of ±20kV.3.When the positive voltage is +35kV,the total dust removal efficiency of the whole experimental system reached the maximum value of 99.9764%.While when the positive voltage increased to +40kV,the total dust removal efficiency dropped to 99.7196%.4.The numerical results showed that the motion of the particles in the flow field not only affected the distribution of the electric field around the particles,but also affects the original velocity field.But this effect is temporary,with the particles moved away,the speed field and the electric field returned to the original state quickly.When different voltage was applied,the velocity field changed in different degrees.The existence of the electric field force had an effect on the motion of the particles,which affects the distribution of the flow field around the particles.Although the particles always move along the direction of the air flow,the presence of the particles undoubtedly disturbs the flow field,making the movement of the particles more complex in the flow field.