多针-水膜电极电晕放电脱硫研究

采用不锈钢多针作为高压电极系统,水膜为低压电极.负直流高压电源供电,含二氧化硫(SO2)的污染气体从高压电极系统的轴向进入,沿着电晕放电电场从水膜上方通过,在电晕放电等离子体和水吸收共同作用下,生成硫酸使SO2得到脱除.主要研究了放电电压、气体中SO2初始浓度和气体在电极系统的停留时间对脱硫效果的影响,并测试了水中SO32-和SI42-离子浓度,分析SO2脱除机制.结果表明,电晕放电和水吸收对SO2脱除具有很好的协同作用,脱硫效果明显升高,SO2转变生成硫酸量的体积分数提高;脱硫效果随电压增加和停留时间的增加而增加,初始浓度对脱硫效果有影响.当SO2初始浓度(体积分数)为430×10-6,施加电压为14.5 kV,停留时间为7.5 s时,脱硫效率达90%以上.

Desulphurization with Multi-Needle-Water Film Electrodes by Corona Discharge

The study of this paper adopted stainless steel multi-needle as a high voltage electrode system, and water film as low voltage electrode. The electrodes were supplied with negative DC high voltage. Polluted gas containing sulfur dioxide (SO₂) flowed into the corona discharge field from the center of the high voltage electrode system in an axis direction, then get across the water surface. Under the effect of corona discharge plasma and water absorption, SO₂ was removed by converting it into sulfuric acid. The effect of the three factors which were the applied voltage, SO₂ inlet concentration and duration of the exposure to the corona discharge on desulphurization efficiency has been studied mostly. Moreover, the concentrations of SO^2-₃ and SO^2-₄ ions in the water were measured and the mechanism of desulphurization was analyzed. The results showed that there was a synergistic effect on the removal of SO₂ when combining corona discharge and water absorption, and both the desulphurization efficiency and the amount of sulfuric acid increased evidently. As the applied voltage and the duration increased, the desulphurization efficiency increased. Also, the SO₂ inlet concentration had effect on desulphurization efficiency. When the SO₂ inlet concentration was 430×10^-6, the voltage was 14.5 kV and the duration was 7.5 s, a desulphurization efficiency of more than 90% could be attained.