【作者】 孙健；

【导师】 白敏冬；

【作者基本信息】 大连海事大学 ， 环境科学与工程， 2007， 硕士

【摘要】 目前，静电除尘器在应用中存在体积大、质量重、投资高及细微粉尘捕集率低下等问题，因此难以满足日益严格的环境污染治理需求。为了保证静电除尘器高效运行，减少粒子在前端荷电区的复合及沉降损失，提高荷电粒子的输运率，本文结合国家自然科学基金资助项目“离子在高气压强电场中运动规律及其应用的基础研究(No.60471036)”及“静电除尘器的交变电场离子荷电凝聚研究(No.50578020)”，采用在强电离放电区域内引入气流作用力的方法，研究平均电场、能量密度及风速等参量对离子输运特性的影响，在此基础上提出了进一步促进离子输出的有效方法，取得的主要结果如下： 1) 不同风速下荷电区与凝并区的气流流场模拟显示，基本上没有明显的局部气流停滞及局部气流流速差异较大的现象；高速流场中的湍流影响较小，使束缚在电场中的带电粒子更易输出，提高了场外带电粒子浓度，进而使凝并区中的粉尘粒子捕集效率更高； 2) 在一个大气压，温度为20℃，风速分别为5m／s、10m／s的条件下，平均电场强度、能量密度等参量对离子输运率的影响程度仅在1个数量级内；而在相同条件下，通过提高离子动量的方法可以使离子输运率提高2个数量级。因此，提高带电粒子的动量是解决离子输运问题的有效方法之一； 3) 根据高流速流场中离子碰撞运动原理研制小型化离子浓度测试仪，在一定条件下摆脱了平板式测试仪对取样风速的限制，实现了高风速下(5～25m／s)离子浓度的测量。另外，新型离子浓度探测仪对测量环境扰动较小，极适于定点测量，为研究静电除尘器内部带电粒子的空间分布提供了较适宜的测试设备。 在以上实验结果的基础上，可将荷电区置于捕集区前端风速较高(约20m／s)的通风管道内部，不仅可以使除尘器更加稳定高效，还可减小除尘器的占用空间，使静电除尘器的体积、能耗及运行费用都会有所降低；同时新型离子浓度测试仪的应用，也会使静电除尘器中的离子数据测量更加简便。更多还原

【Abstract】 Electrostatic Precipitators of today are difficult to meet the increasingly strict environment treating standard because the volume of Electrostatic Precipitator is huge, which means that the price of initial investment, operation cost are extremely high, and the efficiency of dust removing for micro dust is too low. In order to improve the transport rate of charged particles and the efficiency of Electrostatic Precipitator, and to induce the loss in recombination and sedimentation, a new approach is investigated by introducing an applied force of horizontal gas into a strong ionization discharge field and models of influence of average electric field intensity, ionization density and gas flow rate on the transport rate of particles are established based on the key NSFC Project "Study of Method and Application of Gas Molecules Ionized with Strong Electric Field at High Pressure"(No.60471036) and "Studies on Charging and Sedimentation of particles in AC electric field of Electrostatic Precipitator" (No.50578020). At the same time, a new method of detecting the electron density in high pressure is investigated. The main achievements are as follows:1) The analog results for charging region and condensation region at different flow velocities indicate that there are no remarkable local irregularities or significant difference, and that the turbulent flow at a high speed is less apparent than that at a low speed, which causes charged particles to be easily transported out from the electric field. Therefore, the density of charged particles is increased, which is beneficial to the efficiency of Electrostatic Precipitator;2) At the gas velocity of 5m/s and 10m/s, 20°C and 1atm, the influence of average electric field intensity and ionization density on transport rate of particles is less than 1 order of magnitude; The influence of particle momentum on transport rate is more than 2 orders of magnitude. Therefore, it is one of the methods for increasing charged particle density by increasing their momentum;更多还原