不同烟气流速下线板式电除尘器中磁场效应验证

Verification of magnetic field effect in a wire-plate plate electrostatic precipitator at different flue gas velocities

为进一步提高线板式静电除尘器(ESP)的除尘效果、减少细微颗粒物随烟气的逃逸,将磁场引入其中,模拟了特征颗粒粒径2.5μm、工作电压50 kV条件下的除尘效率,探究了不同烟气流速下磁场对细微颗粒物捕集性能的影响。结果表明:磁场能有效改变带电颗粒的运动轨迹,大幅度提高细微颗粒物的除尘性能;颗粒在低烟气流速条件下,偏向收尘板的趋势更明显,更有利于颗粒物的捕集;外加磁场在高烟气流速时对除尘效率提升作用更显著,且这一提升幅度随着磁感应强度的增大而不断增大并趋于平缓;随着磁感应强度不断减小,烟气流速降低除尘效率的幅度逐步增大,直至无磁场环境时达到最大。以上研究结果可为磁场在静电除尘器的应用提供参考,对改善ESP的除尘性能具有重要意义。

In order to further improve the dust removal effect of a wire-plate electrostatic precipitator(ESP)and reduce the escape of fine particles with flue gas, the magnetic field was introduced into ESP. The dust removal efficiency was numerically simulated with characteristic particle of 2.5 μm at the working voltage of 50 kV, and the influence of magnetic field on the trapping performance of fine particles at different flue gas velocities was explored. The results showed that the magnetic field could effectively change the trajectory of charged particles and greatly improve the dust removal performance of fine particles. The tendency of particles leaning towards dust collection plate was more obvious under the condition of low flue gas velocity, which is more conducive to the capture of particulate matter. The promotion effect of magnetic field on dust removal efficiency was more significant at high flue gas velocity, and with the increase of magnetic induction intensity,the promotion range continued to increase, then tended to be flat. As the magnetic induction intensity decreased,the decrease range of dust removal efficiency caused by flue gas velocity increased gradually and reached its maximum in the absence of magnetic field. The research results can provide guidance for the application of magnetic field in ESP and have important significance for improving ESP’s dust removal performance.