中试平台SCR低温催化剂测试与氨逃逸分布特征

doi:10.16085/j.issn.1000-6613.2020-1844

摘要/Abstract

摘要：

目前燃煤机组低负荷运行的情况越来越多，研究机组低负荷运行时NO_x控制技术可有效降低燃煤机组的NO_x排放浓度。本文利用已建成的20000m³/h的实际燃煤烟气的污染物脱除试验平台，安装低温段脱硝催化剂整体模块，测试该催化剂的性能指标，现场取样并重点分析氨逃逸和转化率指标，得出实际烟气条件下氨逃逸分布特征。结果表明：该低温脱硝催化剂的低温段在290~250℃范围内，脱硝效率可达到80%，脱硝出口NO_x可控制在50mg/m³（标准）以内，甚至20mg/m³以内，氨逃逸最高为1.68mg/m³，小于标准要求值2.28mg/m³，SO₂/SO₃转化率最高为0.73%，小于标准要求值1%，满足运行要求。文中进一步研究了氨逃逸浓度沿程分布情况，经测试表明，290℃时沿程氨逃逸浓度不断降低，除尘器前降低32.2%，除尘器后降低65.5%。

关键词: 选择性催化还原低温催化剂, 氨逃逸分布特征, SO₂/SO₃转化率, 实际燃煤烟气, 中试平台

Abstract:

At present, there are more and more low-load operations of coal-fired units. The study on the deNO_x control technology of low-load operation can effectively reduce the NO_x emission of coal-fired units. The established real-time flue gas pollutant removal pilot test platform with 20000m³/h was used to analyze the performance indexes, in which the whole modules of the low-temperature denitration catalysts were installed into the SCR system. The NH₃ slip concentration and SO₂/SO₃conversion rate were sampled on-site and analyzed, the NH₃ slip distribution characteristics were observed. The results show that when the low-temperature catalyst range is 290—250℃, the denitration efficiency is about 80%, and the NO_x at the SCR outlet can be controlled within 50mg/m³, even within 20mg/m³, meanwhile, the maximum NH₃ slip is 1.68mg/m³, which is less than 2.28mg/m³, required by the criterion. The maximum SO₂/SO₃ conversion rate is 0.73%, which is less than 1%, required by the criterion. All these indexes meet the operation requirements. The distribution of NH₃ slip along the pollution control process is further studied. The results show that the NH₃ slip concentration is continuously decreased along the way. The NH₃ slip concentration at ESP inlet is decreased by 32.2% and 65.5% at the ESP outlet, respectively.

Key words: low temperature SCR catalyst, NH₃-slip distribution characteristics, SO₂/SO₃conversion rate, real coal-fired flue gas, pilot platform

中图分类号:

O643.36

赵瑞, 张翼, 余学海, 史晓宏, 刘毅, 王鹏, 韩涛. 中试平台SCR低温催化剂测试与氨逃逸分布特征[J]. 化工进展, 2021, 40(8): 4610-4615.

ZHAO Rui, ZHANG Yi, YU Xuehai, SHI Xiaohong, LIU Yi, WANG Peng, HAN Tao. SCR low-temperature catalyst test and NH₃-slip distribution profile on the pilot platform[J]. Chemical Industry and Engineering Progress, 2021, 40(8): 4610-4615.

图/表 10

图1 控制冷凝法采样系统

图2 试验测试点位示意

图3 中试平台烟气量及脱硝入口NOx浓度（250℃）

图4 250℃时NOx进出口浓度及脱硝效率

图5 中试平台烟气量及脱硝入口NOx浓度（290℃）

图6 290℃时NOx进出口浓度及脱硝效率

图7 脱硝入口温度对氨逃逸浓度的影响

图8 SO2/SO3转化率与催化剂温度的关系

图9 275℃时各检测点位的氨逃逸浓度

图10 不同温度下各测试点位的氨逃逸浓度

参考文献 22

1	环境保护部，国家质量监督检验检疫总局. 火电厂大气污染物排放标准: [S]. 北京: 中国环境科学出版社, 2012.
	Ministry of Ecology and Enviroment of the People’s Republic of China; General Administration of Quality Supervision, Inspection and Quarantine of the People’s Republic of China. Emission standard of air pollutants for thermal power plants: [S]. Beijing: China Environment Science Press, 2012.
2	张道军, 马子然, 孙琦, 等. 选择催化还原(SCR)反应机理研究进展[J]. 化工进展, 2019, 38(4): 1611-1623.
	ZHANG Daojun, MA Ziran, SUN Qi, et al. Progress in the mechanism of selective catalytic reduction (SCR) reaction[J]. Chemical Industry and Engineering Progress, 2019, 38(4): 1611-1623.
3	王树民, 余学海, 顾永正, 等. 基于燃煤电厂“近零排放”的大气污染物排放限值探讨[J]. 环境科学研究, 2018, 31(6): 975-984.
	WANG Shumin, YU Xuehai, GU Yongzheng, et al. Discussion of emission limits of air pollutants for ‘near-zero emission’ coal-fired power plants[J]. Research of Environmental Sciences, 2018, 31(6): 975-984.
4	金侃, 张军, 郑成航, 等. 百万燃煤机组烟气污染物超低排放改造费效评估[J]. 环境工程学报, 2017, 11(2): 1061-1068.
	JIN Kan, ZHANG Jun, ZHENG Chenghang, et al. Economical assessment of ultra-low pollutants emission technology innovation for coal-fired power plants[J]. Chinese Journal of Environmental Engineering, 2017, 11(2): 1061-1068.
5	SONG W H, OUYANG Z Q, WANG M H, et al. The combustion and NO_x emission characteristics of the ultra-low volatile fuel using the novel pulverized coal self-sustained preheating combustion technology[J]. Fuel, 2020, 271: 117592.
6	LIN F W, WANG Z H, ZHANG Z M, et al. Flue gas treatment with ozone oxidation: an overview on NO_x, organic pollutants, and mercury[J]. Chemical Engineering Journal, 2020, 382: 123030.
7	马大卫, 何军, 张其良, 等. SCR脱硝系统性能及空气预热器阻力上升分析[J]. 中国电力, 2019, 52(6): 187-192.
	MA Dawei, HE Jun, ZHANG Qiliang, et al. Analysis and research on SCR system performance and resistance increase of air preheater in ultra-low emission unit[J]. Electric Power, 2019, 52(6): 187-192.
8	张萼松. SCR催化剂表面硫酸氢铵分解机制及催化剂改性研究[D]. 武汉: 华中科技大学, 2019.
	ZHANG Esong. Study of decomposition mechanism of ABS on surface of SCR catalyst and catalyst modification[D]. Wuhan: Huazhong University of Science and Technology, 2019.
9	张道军, 马子然, 孙琦, 等. 硫酸氢铵在钒基选择性催化还原催化剂表面的生成、作用及防治[J]. 化工进展, 2018, 37(7): 2635-2643.
	ZHANG Daojun, MA Ziran, SUN Qi, et al. Formation mechanism, effects and prevention of NH₄HSO₄ formed on the surface of V₂O₅ based catalysts[J]. Chemical Industry and Engineering Progress, 2018, 37(7): 2635-2643.
10	沈建军, 禾志强. 燃煤电厂超低排放形势下空预器堵塞预防措施[J]. 环境保护科学, 2017, 43(1): 88-91.
	SHEN Jianjun, HE Zhiqiang. Prevention measures for air-preheater blockage in super-low emission situation of coal-fired power plants[J]. Environmental Protection Science, 2017, 43(1): 88-91.
11	王争荣, 汪洋, 夏怀鹏, 等. 1000MW燃煤机组SCR脱硝系统喷氨精细化改造[J]. 华电技术, 2019, 41(10): 1-7.
	WANG Zhengrong, WANG Yang, XIA Huaipeng, et al. Delicacy control on ammonia injection for SCR denitration system in a 1000MW coal-fired unit[J]. Huadian Technology, 2019, 41(10): 1-7.
12	胡建根, 童家麟, 茅建波, 等. 典型燃煤锅炉深度调峰能力比较研究[J]. 锅炉技术, 2019, 50(6): 59-64.
	HU Jiangen, TONG Jialin, MAO Jianbo, et al. The research of the comparision of deep peak regulation capacity for typical coal-fired boilers[J]. Boiler Technology, 2019, 50(6): 59-64.
13	姚宣, 郑鹏, 郑伟. SCR脱硝系统最低连续喷氨温度的研究[J]. 中国电力, 2016, 49(1): 146-150.
	YAO Xuan, ZHENG Peng, ZHENG Wei. Study on minimum continuous-operation temperature of SCR system[J]. Electric Power, 2016, 49(1): 146-150.
14	胡冬. 脱除烟气SO₃实现SCR宽负荷脱硝的可行性分析[J]. 中国电力, 2019, 52(3): 49-55.
	HU Dong. Feasibility analysis on the application of SO₃ removal technology in coal-fired power units at low load SCR operation[J]. Electric Power, 2019, 52(3): 49-55.
15	张广才, 李锐攀, 朱学智, 等. 超超临界锅炉及SCR参数精细化控制实现NO_x浓度实时达标的优化与应用[J]. 环境工程技术学报, 2018, 8(6): 586-592.
	ZHANG Guangcai, LI Ruipan, ZHU Xuezhi, et al. Optimization and application of accurate control of ultra-supercritical boiler and SCR parameters for NO_x real time value up to the standard[J]. Journal of Environmental Engineering Technology, 2018, 8(6): 586-592.
16	郭林, 任景行, 赵勇刚, 等. 燃煤烟气低温NH₃-SCR脱硝工艺中试[J]. 化工进展, 2020, 39(4): 1371-1377.
	GUO Lin, REN Jinghang, ZHAO Yonggang, et al. Pilot test on low temperature NH₃-SCR denitration of coal-fired flue gas[J]. Chemical Industry and Engineering Progress, 2020, 39(4): 1371-1377.
17	周佳丽, 马子然, 王宝冬, 等. 燃煤电厂宽温催化剂的开发与应用示范[J]. 电力科技与环保, 2019, 35(2): 47-52.
	ZHOU Jiali, MA Ziran, WANG Baodong, et al. Development and application demonstration of SCR catalyst for coal-fired power plants in wide temperature[J]. Electric Power Technology and Environmental Protection, 2019, 35(2): 47-52.
18	石磊. 硫酸氢铵生成机理及检测技术研究[D]. 西安: 西安热工研究院有限公司, 2019.
	SHI Lei. Formation mechanism and detection technology of ammonium bisulfate[D]. Xi’an: Xi’an Thermal Power Research Institute Co.,Ltd., 2019.
19	王猛, 禾志强. 脱硝系统氨逃逸测试方法浅析[J]. 能源与节能, 2019(8): 55-58.
	WANG Meng, HE Zhiqiang. Analysis on the measuring method of ammonia slip in denitrification system[J]. Energy and Energy Conservation, 2019(8): 55-58.
20	中华人民共和国国家质量监督检验检疫总局，中国国家标准化管理委员会. 燃煤烟气脱硫设备性能测试方法: [S]. 北京: 中国标准出版社, 2008.
	General Administration of Quality Supervision, Inspection and Quarantine of the People’s Republic of China; Standardization Administration of the People’s Republic of China. National Standard (Recommended) of the People’s Republic of China: Performance test method for coal-fired flue gas desulphurization equipment: [S]. Beijing: Standards Press of China, 2008.
21	卿梦霞, 张鑫, 刘亮, 等. 燃煤烟气脱硝副产物硫酸氢铵/硫酸铵沉积与分解特性研究[J]. 化工学报, 2021, 72(2): 1132-1141.
	QING Mengxia, ZHANG Xin, LIU Liang, et al. Study on deposition and decomposition characteristics of ammonium bisulfate/ammonium sulfate as by-product of denitration in coal-fired flue gas[J]. CIESC Journal, 2021, 72(2): 1132-1141.
22	郑方栋. SCR脱硝烟气中硫酸氢铵的生成机理研究[D]. 杭州: 浙江大学, 2017.
	ZHENG Fangdong. Study on ammonium bisulfate formation mechanism in SCR flue gas[D]. Hangzhou: Zhejiang University, 2017.

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