依托Ansys Fluent平台及其二次开发程序建立静电除尘器（ESP）内除尘及活性炭汞吸附的数值模型，多场模型耦合了流场、电场、颗粒吸附、颗粒荷电及颗粒运动等子模型，通过该模型对静电除尘器内喷射活性炭汞吸附及颗粒收集的机理和影响因素进行探讨。结果表明活性炭颗粒粒径和ESP内的离子风效应对于除汞除尘效率均有重要影响。活性炭颗粒粒径越小，除汞效率越高，当活性炭粒径为5 μm时，ESP脱汞效率可达89.6%。而离子风的作用对于ESP内两种汞吸附机制有着不同的影响。其中，在ESP内悬浮活性炭颗粒对于汞的吸附机制占主导地位，而近壁面汞吸附效率较低，最大除汞效率不超过10%。将汞吸附子模型的计算结果与实验结果进行对比验证，发现该模型能较好地预测活性炭的脱汞率。
Based on the Ansys Fluent platform along with its secondary development programs, this research developed a comprehensive numerical model for mercury capture by activated carbon injection and particle migration within an electrostatic precipitator (ESP). The multi-field model coupled sub-models such as flow field, electric field, mercury adsorption, particle charging, and particle motion. The mechanisms and crucial operation parameters of mercury adsorption by suspended activated carbon particles in electrostatic precipitators are fully discussed. The results show that both activated carbon particle size and ion wind effects have great impacts on combined removal efficiency of the mercury and particles. Reducing the size of sorbent particles (activated carbon) can promote mercury removal efficiency while decreasing the particle collection efficiency,the mercury removal efficiency will be 89.6% while the particle size is 5 μm. Additionally, the ion wind has distinct effects on the two mercury adsorption mechanisms in an ESP where the adsorption mechanism of mercury by suspended activated carbon particles is dominant, while the mercury capture efficiency near the wall is at a low level which is below 9%. The comparison between the experimental data and numerical results demonstrates that this model is able to predict the mercury removal efficiency by powdered sorbent injection with acceptable accuracy.
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