Research on Flue Gas Heater for Urea Pyrolysis of SCR Flue Gas De-NOx System

doi:10.11930/j.issn.1004-9649.2017.01.177.04

Abstract

Abstract: In the SCR(Selective Catalytic Reduction, SCR) denitrification system adopting urea as the reducing agent, the power consumption of the electric heater in front of the pyrolysis furnace is high. In order to reduce the power consumption, in the technical retrofit of the 640-MW unit in a power plant, the electric heater is modified as a bypass system, a high temperature flue gas heater is installed and the high temperature flue gas is used to heat the hot primary air. The high temperature flue gas, of which the temperature is about 650 ℃ and the flow is about 6 000 m3/h under standard state, is induced from the horizontal flue between the high temperature and the low temperature reheaters. The technical route is analyzed, and the retrofit effect is verified by variable load tests. The data analysis shows that the technical route is feasible and easy to implement, also the system runs well. Therefore, the high temperature flue gas heater can completely replace the electric heater reducing the house service rate and power supply costs.

Key words: coal-fired power plant, SCR flue gas de-NOx, urea pyrolysis, electric heater, high temperature flue gas heater

CLC Number:

TM621

XU Wei. Research on Flue Gas Heater for Urea Pyrolysis of SCR Flue Gas De-NOx System[J]. Electric Power, 2017, 50(1): 177-180.

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URL: https://www.electricpower.com.cn/EN/10.11930/j.issn.1004-9649.2017.01.177.04

https://www.electricpower.com.cn/EN/Y2017/V50/I1/177

References

[1] TOKMAKOV I V, ALAVI S, THOMPSON D L. Urea and urea nitrate decomposition pathways: a quantum chemistry study [J]. The Journal of Physical Chemistry, 2006, 110(8): 2759-2770.
[2] 郭伟,崔宁. 尿素热解制氨SCR脱硝技术在电厂的应用与优化[J]. 锅炉技术,2012,43（3）：77-80.
GUO Wei, CUI Ning. Application and optimization of urea pyrolysis to prepare ammonia SCR denitrification technology in power plant [J]. Boiler Technology, 2012, 43(3): 77-80.
[3] 惠润堂,韦飞,闫世平,等. 国产首套尿素水解装置在大型火电厂的工业应用及技术优化[J]. 中国电力,2014,47（7）：150-155.
HUI Runtang, WEI Fei, YAN Shiping, et al . The industrial application and technical optimization of first domestically-made urea hydrolysis unit in large power plants[J]. Electric Power, 2014, 47(7): 150-155.
[4] 陈海彩,张军,沈乐,等. 火电厂尿素热解和水解工艺研究[J]. 电力科学与工程,2014,30（6）：16-19.
CHEN Haicai, ZHANG Jun, SHEN Le, et al . Study of technology of urea pyrolysis and hydrolysis in thermal power plant[J]. Electric Power Science and Engineering, 2014, 30(6): 16-19.
[5] 赵冬贤,刘绍培,吴晓峰,等. 尿素热解制氨技术在SCR脱硝中的应用[J]. 热力发电,2009,38（8）：65-67.
ZHAO Dongxian, LIU Shaopei, WU Xiaofeng, et al . Application of urea pyrolysis to prepare ammonia technology into SCR denitrification [J]. Thermal Power Generation, 2009, 38(8): 65-67.
[6] 杨志忠,叶茂,宋晓宏,等. 一种SCR脱硝还原剂尿素热解热源供给装置：201320179396.1[P]：2013-04-11.
[7] 叶茂,杨志忠,晏顺娟,等. SCR烟气脱硝尿素热解用炉内气气换热器技术研究[J]. 东方电气评论,2015,29（2）：76-82.
YE Mao, YANG Zhizhong, YAN Shunjuan, et al . Research on the flue gas-air heat exchanger of urea pyrogenation for SCR flue gas de-NO x technology [J]. Dongfang Electric Review, 2015, 29(2):76-82.
[8] 喻小伟,李宇春,蒋娅,等. 尿素热解研究及其在脱硝中的应用[J]. 热力发电,2012,41（1）：1-5.
YU Xiaowei, LI Yuchun, JIANG Ya, et al . Study on pyrolysis of urea and its application in denitrifcation[J]. Thermal Power Generation, 2012, 41(1): 1-5.

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