Direct current corona discharge was investigated to reduce nitrogen oxide (NOx) emissions from a 15-kW small-scale biomass boiler. The electrostatic precipitator was designed and operated under different regimes with both positive and negative polarities. A reduction in NOx concentration from 200 mg/m to 44/46 mg/m for positive/negative polarities was achieved, corresponding to a NOx removal efficiency of approximately 78 %. However, the specific input energy required for a positive corona (35.7 J/L) was lower than that for a negative corona (48.4 J/L), indicating an energy efficiency advantage for positive polarity. The results were analysed for NO decontamination involving reactions with OH radicals, ground-state oxygen atoms, and ozone. Positive corona favoured NOx removal via reactions with OH (21 % efficiency) and oxidation by oxygen (12 % efficiency), whereas negative corona promoted NO oxidation by ozone (75 % efficiency). The distinct distribution of electrons and active species, influenced by the non-uniform electric field and polarity, governs plasma chemical kinetics.

中文翻译：

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直流电晕中小规模生物质燃烧的氮氧化物去除：放电极性对等离子体化学动力学的影响


研究了直流电晕放电以减少 15 kW 小型生物质锅炉的氮氧化物 (NOx) 排放。静电除尘器被设计并在具有正负极性的不同状态下运行。正/负极性时，NOx 浓度从 200 mg/m3 降低至 44/46 mg/m3，相当于约 78% 的 NOx 去除效率。然而，正电晕所需的比输入能量（35.7 J/L）低于负电晕所需的比输入能量（48.4 J/L），表明正极性具有能量效率优势。对涉及 OH 自由基、基态氧原子和臭氧反应的 NO 净化结果进行了分析。正电晕有利于通过与 OH 反应（21% 效率）和氧气氧化（12% 效率）去除 NOx，而负电晕则促进臭氧对 NO 的氧化（75% 效率）。电子和活性物质的独特分布受不均匀电场和极性的影响，控制着等离​​子体化学动力学。