摘要
低温等离子体脱除氮氧化物是近年来废气净化领域的研究热点。为此基于能够实现大面积均匀稳定低温等离子体的氢氧化钠液体电极介质阻挡放电,研究了气体停留时间、气体体积流量和氢氧化钠溶液浓度对氮氧化物去除率的影响。研究发现,氮氧化物去除率随气体体积流量和氢氧化钠溶液浓度的增加而显著增加,在1L/min气流体积流量、3mol/L碱液浓度反应条件下,氮氧化物去除率达到了87%-91%;气体停留时间为30s以上时,氮氧化物去除率达到饱和值90%。研究中采用发射光谱法对低温等离子体中活性基团的类型及分布特征进行了诊断分析。结果表明,液相电极为氢氧化钠溶液的介质阻挡放电比液相为水的放电产生更多的羟基,羟基反应在氮氧化物去除过程中起主导作用。氢氧化钠液体电极介质阻挡放电在NOx去除方面具有良好应用前景。
Recently, the removal of nitrogen oxide emission by low temperature plasma is a hot topic in the field of researching tail gas purification. We used a new sort of dielectric barrier discharge whose ground electrode was made of sodium hydroxide solution to generate a large-scale and stable non-thermal plasma. By this plasma, the effects of gas treatment time, the gas flow rate, and the concentration of sodium hydroxide solution on the removal rate of nitrogen oxide were studied. The results show that the removal rate of nitrogen oxide is increased with the gas flow rate and solution concentration, and when the nitrogen oxide emission is treated at 1 L/min flow, 3 mol/L sodium hydroxide solution, the removal rate can reach the highest level ranging from 87 to 91 percent. When the gas treatment time is over 30 seconds, the removal rate reaches about 90 percent and never remarkably changed. During experiments, the types and distribution characteristics of active groups in plasma were also diagnosed by emission spectroscopy analysis. It can be found that more hydroxide radicals are produced by sodium hydroxide discharges than those using pure water as ground electrode, and hydroxy reactions play a leading role in the process of nitrogen oxide emission treatment.Dielectric barrier discharge whose ground electrode is made of sodium hydroxide solution has a good application prospect in NOx removal.
作者
杨国清
曹一崧
邵朱夏
王德意
贾嵘
YANG Guoqing;CAO Yisong;SHAO Zhuxia;WANG Deyi;JIA Rong(State Key Laboratory of Eco-hydraulics in Northwest Arid Region of China,Xi'an 710048,China;Institute of Water Resource and Hydroelectric Engineering,Xi'an University of Technology,Xi'an 710048,China)
出处
《高电压技术》
EI
CAS
CSCD
北大核心
2018年第12期4013-4019,共7页
High Voltage Engineering
基金
国家自然科学基金(51279161)
西北旱区生态水利工程国家重点实验室基金(2016ZZKT-12)
陕西省教育厅基金(16JK1562)~~
