Applicability Analysis on the Structure Model and Numerical Model for the SCR System

doi:10.11930/j.issn.1004-9649.201803006

Abstract

Abstract: The accuracy and adaptability of the structure model and numerical model were discussed scantly in the numerical calculation for the thermal power plant SCR system. Therefore, in this paper both the complete and the partial structural models were established based on the structural characteristics of the typical SCR system, then simulated using the Fluent software with standard κ-ε turbulence model and Realizable κ-ε turbulence model. Through the comparison of velocities between the simulation and experiment results, the impacts of the turbulence model and the economizer export, the ash hopper, the AIG and the uniform flow grille pattern on the calculation accuracy of flue gas flow field were analyzed. Similarly, by comparing the simulation and experiment results regarding the pressure drops, the NO_x concentration distribution and NH₃ escape distribution in the outlet flue, the method correctness and validity of parameter setting in the porous medium model as well as the multi-component reaction model were also demonstrated respectively The results showed that the economizer export structure and the AIG structure had significant impacts on the calculation accuracy of the flue gas flow field in the inlet flue. The relative error between the simulated and experimental pressure drop across single layer of catalyst was -1.9%. The NO_x removal efficiency of simulation and experiment were 79.35% and 80.56%, respectively with the relative error -1.5%. The NH₃ escape distribution trends of the simulation and experiment result were consistent as well.

Key words: thermal power plant, flue gas de-NO_x, numerical simulation, structure model, porous media, chemical reaction, denitrification efficiency, ammonia escape

CLC Number:

X701
TM621

XIAO Yujun, ZOU Yihui, LI Caiting, ZHOU Xuebin. Applicability Analysis on the Structure Model and Numerical Model for the SCR System[J]. Electric Power, 2019, 52(3): 146-152,160.

Add to citation manager EndNote|Ris|BibTeX

URL: https://www.electricpower.com.cn/EN/10.11930/j.issn.1004-9649.201803006

https://www.electricpower.com.cn/EN/Y2019/V52/I3/146

References 26

[1]	环境保护部. 2016中国环境状况公报[R]. 中华人民共和国环境保护部, 2017.
[2]	LEI Z G, WEN C P, CHEN B H. Optimization of internals for selective catalytic reduction (SCR) for NO removal[J]. Environmental Science & Technology, 2011, 45:3437-3444.
[3]	徐妍, 李文彦. SCR脱硝反应器导流板的结构设计[J]. 热力发电, 2008, 37(10):49-52 XU Yan, LI Wenyan. Structure design of baffle platens in SCR denitrification reactor[J]. Thermal Power Generation, 2008, 37(10):49-52
[4]	胡劲逸. 氨逃逸浓度场的SCR喷氨协调优化控制[D]. 杭州:浙江大学, 2014.
[5]	肖育军, 吴仁军, 陶莉, 等. SCR系统超洁净排放调整与出口NOx均匀性分析[J]. 环境工程学报, 2017, 11(9):5122-5129 XIAO Yujun, WU Renjun, TAO Li, et al. Ultra clean emissions adjustment and uniformity analysis of export NOx for SCR systems[J]. Chinese Journal of Environmental Engineering, 2017, 11(9):5122-5129
[6]	JIN M C, JEONG W C, SUNG H H, et al. Application of computational fluid dynamics analysis for improving performance of commercial scale selective catalytic reduction[J]. Korean Journal of Chemical Engineering, 2006, 23(1):43-56.
[7]	刘欢. 燃煤锅炉烟气SCR脱硝反应器流场的数值模拟与优化研究[D]. 长沙:长沙理工大学, 2010.
[8]	周丽丽. 烟气脱硝反应器气体预分布器结构和混合性能研究[D]. 北京:北京化工大学, 2010.
[9]	陈莲芳. 脱硝反应器流场与反应物混合模拟优化[D]. 济南:山东大学, 2011.
[10]	LIU X Y, LEI Z G, JIA M R. Modeling of selective catalytic reduction (SCR) for NO removal using monolithic honeycomb catalyst[J]. Energy&Fuels, 2009, 23:6146-6151.
[11]	周英贵. 大型电站锅炉SNCR/SCR脱硝工艺试验研究、数值模拟及工程验证[D]. 南京:东南大学, 2016.
[12]	安晓玲. SCR法烟气脱硝技术的数值模拟[D]. 保定:华北电力大学, 2008.
[13]	于帅. 燃煤电厂烟气脱硝装置的优化仿真设计研究[D]. 保定:华北电力大学, 2013.
[14]	潘伶, 杨沛山, 曹友洪. SCR脱硝反应器烟道内部流场的数值模拟与优化[J]. 环境工程学报, 2015, 9(6):2919-2924 PAN Ling, YANG Peishan, CAO Youhong. Simulated calculation and optimization of internal flow field of selective catalytic reduction denitrification reactor flue[J]. Chinese Journal of Environmental Engineering, 2015, 9(6):2919-2924
[15]	韩发年, 闫志勇. SCR烟气脱硝工艺喷氨混合装置研究进展[J]. 化工进展, 2015, 34(12):4151-4157 HAN Fanian, YAN Zhiyong. Numerical simulation and experimental verification of chemical reactions for SCR DeNOx[J]. Chemical Industry and Engineering Progress, 2015, 34(12):4151-4157
[16]	辛晓菲. 300MW燃煤机组SCR脱硝系统优化及数值模拟[D]. 郑州:华北水利水电学院, 2013.
[17]	MAROCCO L, INZOLI F. Multiphase euler-lagrange CFD simulation applied to wet flue gas desulphurisation technology[J]. International Journal of Multiphase Flow, 2009, 35:185-194.
[18]	XIAO Y J, LI C T, LI S H, et al. Optimal design of a wet-type desulphurization absorber by the numerical simulation method[J]. Chemical Engineering Research and Design, 2014, 92:1257-1266.
[19]	SHIH T H, ZHU J. A realizable reynolds stress algebraic equation model[J]. Symposium on Turbulence Shear Flows, 1993, 9:10-18.
[20]	ZHANG Q, FAN Y L, LI W Y. Numerical simulation and experimental verification of chemical reactions for SCR DeNOx[J]. Frontiers of Chemical Engineering in China, 2010, 4(4):523-528.
[21]	Fluentlnc. Fluent User'S Guide[M]. Fluent lne., 2003.
[22]	毛剑宏. 大型电站锅炉SCR烟气脱硝系统关键技术研究[D]. 杭州:浙江大学, 2011.
[23]	郭金龙. 火电机组选择性催化还原脱硝喷氨的优化控制[D]. 北京:华北电力大学, 2011.
[24]	DUMESIC J A, TOPSOE N Y, TOPSOE H, et al. Kinetics of selective catalytic reduction of nitric oxide by ammonia over vanadia/titania[J]. Journal of Catalysis, 1996:409-417.
[25]	姜烨, 高翔, 吴卫红, 等. V2O5/TiO2催化剂上NH3选择性催化还原NO反应动力学研究[J]. 应用化工, 2012, 41(12):2047-2049 JIANG Ye, GAO Xiang, WU Weihong, et al. Kinetic study on catalytic reduction of NO with NH3 over V2O5/TiO2 catalysts[J]. Applied Chemical Industry, 2012, 41(12):2047-2049
[26]	曹蕃, 苏胜, 向军, 等. SCR反应过程中NO/NH3在γ-Al2O3表面吸附特性[J]. 化工学报, 2014, 65(10):4057-4062 CAO Fan, SU Sheng, XIANG Jun, et al. NO/NH3 adsorption properties on γ-Al2O3 surface during SCR process[J]. CIESC Journal, 2014, 65(10):4057-4062