Modeling And Simulation Of Dust Removal Base On Magnetoelectricity Grading Coagulation

The bottleneck of the Electrostatic precipitators (ESP) is low efficiency for collection of submicron particle, especially for PM2.5. An alternate way to increase its efficiency is to enforce the coagulation and, thereby, form larger particles. Submicron particle removal efficiency is relatively high when the ESP is base on AC electric coagulation, but AC aggregator requires more power consumption, in order to reduce energy consumption and keep quite coagulation coefficient, we firstly proposed magnetoelectricity grading coagulation aggregator.Magnetoelectricity grading aggregator refers to the aggregator of which the first half is magnetic field produced by permanent magnets and the second half is AC electric field. Increase the link of Magnetic coagulation, reduce the length of AC electric field to the half of their original cost, and thus reduce the power consumption by30%～50%. This paper develop the total efficiency mathematical model of charge-magnetoelectricity grading coagulation-collection process which express the mathematic relation between collection efficiency and particles’ median diameter before coagulation, and we comparative analysis of the following two cases in the aspects of collection efficiency and energy consumption:1、the first half of the aggregator is magnetic field of which the length is1meter, the second half of the aggregator is AC electric field of which the length is1meter.2、the whole period of aggregator is AC electric field of which the length is2meters.1、For AC electric power consumption problems, we put forward the a method of magnetoelectricity grading coagulation and develop the total efficiency mathematical model of charge-magnetoelectricity grading coagulation-collection process. For this model, the results of simulation analysis are as follows:For particles of which the true density are less than1.4g/cm3, the collection efficiency based on magnetoelectricity grading coagulation is higher than which based on AC electric coagulation.2、For the problem of poor effect of weak magnetic dusts’ coagulation, this paper propose a methiod of charged particles coagulating in the magnetic field under Lorentz force. We develop the coagulation model and get coagulation coefficient expression. Through the simulation, we get that the order of magnitude of magnetic coagulation coefficient and AC coagulation coefficient are all10-12m3/s.3、Use the coagulation coefficient we get, then study the number concentration attenuation function and particle size distribution function of bipolarly charged aerosol particles during coagulation, subsequently, the mathematical expression of the total efficiency of charge-coagulation-collection is derived. Through the simulation of the model, we get that when the true density of particles are2g/cm3, compared to the situation of no coagulation, If adding the link of AC electric coagulation, the collection efficiency of PM2.5increases by about27%; if adding the link of magnetic dust coagulation, the collection efficiency of PM2.5increases by about21%; if adding the link of magnetoelectricity grading coagulation, the collection efficiency of PM2.5increases by about25%.4、There is a deviation between the collection efficiency calculated by Deutsch equation and the actual efficiency, so the collection part of the charge-coagulation-collection mathematical model is simulated by Fluent. Comparative analysis shows that the approximate trend of the simulation result of the total efficiency mathematical model of charge-magnetoelectricity grading coagulation-collection process is correct.