微波诱导活性炭激发等离子体射流脱硝实验

doi:10.16085/j.issn.1000-6613.2021-0542

摘要/Abstract

摘要：

微波等离子体直接分解NO有极高的效率，但在有氧条件下分解较难。为解决这一问题，本文提出了一种利用微波诱导活性炭激发等离子体射流在有氧条件下脱硝的新技术。利用微波材料学工作站，通过调整激发等离子体参数（活性炭直径、活性炭质量、微波功率）得到了最佳工艺条件，深入分析了等离子体射流形成过程，并将其用于脱硝实验，研究了不同形态等离子体、NO初始浓度和O₂浓度因素对脱硝的影响。结果表明，以1L/min氮气作载气时，在活性炭直径2mm、质量15g、微波功率2kW条件下，可快速产生等离子体射流且持续时间长久。等离子体用于脱硝实验，射流状等离子体脱硝效率高于闪电状等离子体。NO依次在活性炭床层区和等离子体射流区去除。当O₂体积分数小于4%时，O₂浓度的增加对NO的脱除有促进作用；大于4%时，O₂浓度的增加会产生过量的氧自由基（·O）和大量的CO₂，对NO的脱除产生抑制作用。

关键词: 微波等离子体射流, 活性炭, 脱硝, 还原, 选择性

Abstract:

Decomposition of NO with microwave plasma has a very high efficiency, but it is difficult to remove NO_x in the presence of oxygen. In order to solve this problem, a new denitration technology using microwave-induced plasma emission jet with the activated carbon and under aerobic condition was put forward. In a microwave tube furnace, the best denitration conditions were obtained by adjusting the diameter and amounts of activated carbon, and microwave power. Then the process mechanism was analyzed in-depth. The effects of initial concentrations of NO and O₂ on denitration by plasma jet were also studied. When nitrogen was used as carrier gas with a flow of 1L/min, the diameter of activated carbon was 2mm, the mass of activated carbon was 15g and the microwave power was 2kW, the plasma jet could be generated quickly and held for a long time. In the experiments with plasma jet, the denitration efficiency of jet plasma was higher than that of lightning plasma. NO was removed in the activated carbon bed zone and plasma jet zone successively. When the concentration of O₂ was less than 4%, the increase of O₂ concentration promoted the removal of NO. When the concentration of O₂ was greater than 4%, the free radicals (·O) and a large amount of CO₂ from excessive oxygen inhibited the removal of NO.

Key words: microwave plasma jet, activated carbon, denitration, reduction, selectivity

中图分类号:

X701.3

杨广东, 苏林, 邹志雪, 姜涛. 微波诱导活性炭激发等离子体射流脱硝实验[J]. 化工进展, 2022, 41(2): 1054-1062.

YANG Guangdong, SU Lin, ZOU Zhixue, JIANG Tao. Experimental study on denitrification with microwave induced activated carbon excited plasma jet[J]. Chemical Industry and Engineering Progress, 2022, 41(2): 1054-1062.

图/表 18

图1 煤质柱状活性炭实物图

图2 微波等离子体反应体系示意图1—N2气瓶；2—O2气瓶；3—NO气瓶；4—减压阀；5—质量流量计；6—混气罐；7—微波工作站； 8—观察口； 9—在线烟气分析仪；10—在线煤气分析仪；11—洗气瓶

图3 定制的反应床

表1 激发等离子体射流实验条件

活性炭直径/mm	活性炭质量/g	微波功率/kW
2，4，6	15	2
2	5~50	2
2	15	1，2，3

表2 不同状态等离子脱硝实验条件

组别	微波功率/kW	活性炭质量/g	NO/mg·m^-3
微波无介质组	2	0	500
闪电状等离子体组	2	15	500
等离子体射流组	2	15	500

图4 不同状态等离子体实验活性炭床层状态

表3 脱硝实验条件

活性炭/g	功率/kW	NO/mg·m^-3	O₂（体积分数）/%
15	2	500	0
15	2	500，600，700，800	0
15	2	500	2，4，6，8，10

图5 活性炭粒径对激发时间和持续时间的影响

图6 活性炭质量对激发时间和持续时间的影响

图7 微波功率对激发时间和持续时间的影响

图8 微波诱导活性炭激发等离子体过程图

图9 不同形态等离子脱硝效率

图10 NO的初始浓度对NO的转化率和氮气选择性的影响

图11 NO不同初始浓度随时间变化曲线

图12 不同O2浓度下NO的浓度随时间变化

图13 O2浓度对NO的转化率和氮气选择性的影响

图14 无氧条件下CO、CO2浓度随时间变化曲线图

图15 NO转化率以及CO、CO2平均产率随O2浓度变化图

参考文献 25

1	林晓芬, 张军, 尹艳山, 等. 烟气脱硫脱氮技术综述[J]. 能源环境保护, 2014, 28(1): 1-4.
	LIN Xiaofen, ZHANG Jun, YIN Yanshan, et al. Discussion on techniques of gas desulfurization and denitration[J]. Energy Environmental Protection, 2014, 28(1): 1-4.
2	GALLOWAY J N, TOWNSEND A R, ERISMAN J W, et al. Transformation of the nitrogen cycle: recent trends, questions, and potential solutions[J]. Science, 2008, 320(5878): 889-892.
3	谭青, 冯雅晨. 我国烟气脱硝行业现状与前景及SCR脱硝催化剂的研究进展[J]. 化工进展, 2011, 30(S1): 709-713.
	TAN Qing, FENG Yachen. Present status and perspective of China’s flue gas denitration industry and research progress of SCR catalysts[J]. Chemical Industry and Engineering Progress, 2011, 30(S1): 709-713.
4	管一明, 张伯溪, 关越. 选择性非催化还原法烟气脱氮氧化物工艺[J]. 电力环境保护, 2006, 22(4): 15-19.
	GUAN Yiming, ZHANG Boxi, GUAN Yue. Selective non-catalytic reduction de-NO_x technology[J]. Electric Power Technology and Environmental Protection, 2006, 22(4): 15-19.
5	李芳盛, 张杰, 齐云国, 等. 活性炭联合脱硫脱硝工艺[J]. 化工管理, 2020(4): 189-190.
	LI Fangsheng, ZHANG Jie, QI Yunguo, et al. Activated carbon combined desulfurization and denitration process[J]. Chemical Enterprise Management, 2020(4): 189-190.
6	王承智, 胡筱敏, 石荣, 等. 等离子体技术应用于气相污染物治理综述[J]. 环境污染与防治, 2006, 28(3): 205-209.
	WANG Chengzhi, HU Xiaomin, SHI Rong, et al. The plasma technology for air pollution control[J]. Environmental Pollution & Control, 2006, 28(3): 205-209.
7	NAMBA Hideki, TOKUNAGA Okihiro, TANAKA Tadashi, et al. The study of electron beam flue gas treatment for coal-fired thermal plant in Japan[J]. Radiation Physics and Chemistry, 1993, 42(4/5/6): 669-672.
8	MOISAN M, PELLTTIER J. Microwave induced plasma, plasma technology[M]. Amsterdam: Elsevier Science Publishing, 1992.
9	唐军旺, 杨黄河, 任丽丽, 等. 微波放电脱除NO[J]. 高等学校化学学报, 2002, 23(4): 632-635.
	TANG Junwang, YANG Huanghe, REN Lili, et al. The decomposition of NO in microwave discharge[J]. Chemical Research in Chinese Universities, 2002, 23(4): 632-635.
10	FUTAMURA S, ZHANG A H, YAMAMOTO T. Behavior of N₂ and nitrogen oxides in nonthermal plasma chemical processing of hazardous air pollutants[J]. IEEE Transactions on Industry Applications, 2000, 36(6): 1507-1514.
11	WÓJTOWICZ M A, MIKNIS F P, GRIMES R W, et al. Control of nitric oxide, nitrous oxide, and ammonia emissions using microwave plasmas[J]. Journal of Hazardous Materials, 2000, 74(1/2): 81-89.
12	TANG J W, ZHANG T, MA L, et al. Microwave discharge-assisted NO reduction by CH₄ over Co/HZSM-5 and Ni/HZSM-5 under O₂ excess[J]. Catalysis Letters, 2001, 73: 193-197.
13	丁凝, 谢兆倩. 电晕放电等离子体性质研究[J]. 广东化工, 2011, 38(4): 119-120, 131.
	DING Ning, XIE Zhaoqian. Research on corona discharge plasma properties[J]. Guangdong Chemical Industry, 2011, 38(4): 119-120, 131.
14	张达欣, 于爱民, 金钦汉. 微波-炭还原法处理一氧化氮的研究[J]. 高等学校化学学报等, 1997, 18(8): 1271-1274．
	ZHANG Daxin, YU Aimin, JIN Qinhan. Studies on microwave-carbon reduction method for the treatment of nitric oxide[J]. Chemical Research in Chinese Universities, 1997, 18(8): 1271-1274．
15	杨丽敏, 刘海玉, 谢创举, 等. 微波放电对活性炭脱硝的影响[J]. 中国电机工程学报, 2018, 38(21): 6375-6382, 6500
	YANG Limin, LIU Haiyu, XIE Chuangju, et al. Effect of microwave discharge on activated carbon for denitration[J]. Proceedings of the CSEE, 2018, 38(21): 6375-6382, 6500.
16	李虎. Mn₂O₃/AC微波催化剂微波选择催化还原氮氧化物研究[D]. 湘潭: 湘潭大学, 2013.
	LI Hu. Study on microwave selective catalytic reduction of NO over microwave catalysts Mn₂O₃/AC[D]. Xiangtan: Xiangtan University, 2013.
17	刘贝. 煤基炭微波烟气脱硝的研究[D]. 武汉: 武汉科技大学, 2016.
	LIU Bei. Study on the removal of NO_x flue gas by microwave with coal-based carbon[D]. Wuhan: Wuhan University of Science and Technology, 2016.
18	马双忱, 赵毅, 马宵颖, 等. 活性炭床加微波辐射脱硫脱硝的研究[J]. 热能动力工程, 2006, 21(4): 338-341, 433.
	MA Shuangchen, ZHAO Yi, MA Xiaoying, et al. A study of the desulfuration and denitration on active carbon beds provided with microwave irradiation[J]. Journal of Engineering for Thermal Energy and Power, 2006, 21(4): 338-341, 433.
19	刘烨. 微波椰壳活性炭催化剂同时脱除燃煤烟气中NO_x、Hg⁰的研究[D]. 昆明: 昆明理工大学, 2016.
	LIU Ye. Study on assisting removal of NO_x and Hg⁰ from coal fired flue gas by modified microwave coconut shell activated carbon catalysts[D]. Kunming: Kunming University of Science and Technology, 2016.
20	钟力生, 李盛涛, 徐传骧, 等. 工程电介质物理与介电现象[M]. 西安: 西安交通大学出版社, 2013: 16.
	ZHONG Lisheng, LI Shengtao, XU Chuanxiang, et al. Engineering dielectric physics and dielectric phenomena[M]. Xi’an: Xi’an Jiaotong University Press, 2013: 16.
21	金钦汉. 微波化学[M]. 北京: 科学出版社, 1999: 42.
	JIN Qinhan. Microwave chemistry[M]. Beijing: Scientific Press, 1999: 42.
22	LIU Xitao, QUAN Xie, BO Longli, et al. Temperature measurement of GAC and decomposition of PCP loaded on GAC and GAC-supported copper catalyst in microwave irradiation[J]. Applied Catalysis A: General, 2004, 264(1): 53-58.
23	CHAMBRION P, KYOTANI T, TOMITA A. Role of N-containing surface species on NO reduction by carbon[J]. Energy & Fuels, 1998, 12(2): 416-421.
24	CHA C Y, KIM D S. Microwave induced reactions of sulfur dioxide and nitrogen oxides in char and anthracite bed[J]. Carbon, 2001, 39(8): 1159-1166.
25	梁文俊, 李晶欣, 竹涛, 等. 低温等离子体大气污染控制技术及应用[M]. 北京: 化学工业出版社, 2016: 172-207.
	LIANG Wenjun, LI Jingxin, ZHU Tao, et al. Low temperature plasma air pollution control technology and application[M]. Beijing: Chemical Industry Press, 2016: 172-207.

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