黄俊;李兴磊;阮斌;罗圣;卢志民;姚顺春;
HUANG Jun;LI Xinglei;RUAN Bin;LUO Sheng;LU Zhimin;YAO Shunchun;Guangzhou Zhujiang Electric Power Co.,Ltd.;School of Electric Power,South China University of Technology;Guangdong Province Key Laboratory of Efficient and Clean Energy Utilization;Guangdong Province Engineering Research Center of High Efficiency and Low Pollution Energy Conversion;

• 1:广州珠江电力有限公司
• 2:华南理工大学电力学院
• 3:广东省能源高效清洁利用重点实验室
• 4:广东省能源高效低污染转化与工程技术研究中心

摘要(Abstract)：

在超低排放要求下，SCR脱硝反应器的喷氨过量不仅影响经济性，还会引起空预器堵塞、电除尘积灰、布袋糊袋等问题。为提高SCR入口烟气速度和氨氮物质的量比的均匀性，对某电厂一台300 MW机组一侧SCR反应器进行计算流体力学的模拟和烟道流场优化。以Fluent为主要工具，在分析空塔模型和原导流板布置方案的基础上，对SCR烟道导流板结构进行优化、在喷氨格栅下游布置静态混合器，以实现首层催化剂前截面速度和氨氮物质的量比均匀分布。空塔方案速度相对标准偏差为26.1%,氨氮物质的量比相对标准偏差为24.8%,均达不到工程设计要求；原方案在SCR烟道渐扩处和转角处设置6组导流板，速度和浓度均匀性得到较大改善，速度相对标准偏差为13.9%,达到工程设计要求，而氨氮物质的量比相对标准偏差为15.3%,不符合小于10%的设计要求；优化方案布置的导流板消除了烟气在烟道转角处和渐扩处的漩涡、回流现象，同时安装静态混合器增强混合，使速度相对标准偏差减小至11.4%,氨氮物质的量比相对标准偏差为9.4%,SCR烟道内流场均匀性得到较大改善，速度和浓度均匀性达到设计要求。优化方案的压力损失为706 Pa,达到B级设计要求。合理布置导流板和静态混合器可以提高流场均匀性而不引起过大的压力损失，模拟结果对现场SCR流场优化具有借鉴和指导意义。
Under the requirements of ultra-low emission, the excessive injection of ammonia in the SCR DeNO_x reactor not only affects the economy, but has also causes a series of operation and maintenance problems such as air preheater blockage, electrostatic precipitator fouling, and bag paste. In order to improve the uniformity of SCR inlet flue gas velocity and ammonia-nitrogen molar ratio, the computational fluid dynamics simulation and optimization research of flue flow field on one side SCR reactor of an old 300 MW unit in a certain power plant were carried out. Using Fluent as the main tool and based on the analysis of the empty tower model and the original deflector arrangement, the SCR flue deflector structure was optimized, and a static mixer was arranged downstream of the ammonia injection grid to achieve uniform cross-sectional velocity and ammonia-nitrogen molar ratio in the first layer of catalyst. The relative standard deviation of the velocity of the empty tower scheme is 26.1%,and the relative standard deviation of the ammonia-nitrogen molar ratio is 24.8%,all of which can not meet the engineering design requirements. In the original scheme, six groups of deflectors are set at the gradual expansion and corner of SCR flue, and the uniformity of speed and concentration is greatly improved, the relative standard deviation of the speed is 13.9%,which can meet the engineering design requirements, while the relative standard deviation of the ammonia nitrogen molar ratio is 15.3%,which can not meet the design requirements of less than 10%. The flow deflector arranged in the optimized scheme eliminates the vortex and reflux of flue gas at the flue corner and gradual expansion. Meanwhile, the static mixer is installed to enhance mixing, so that the relative standard deviation of velocity is reduced to 11.4%,and the relative standard of ammonia-nitrogen molar ratio to 9.4%. The uniformity of the flow field in the SCR flue has been greatly improved and the speed and concentration uniformity meet the design requirements. At the same time, the pressure loss of the optimized scheme is 706 Pa, which meets the B-level design requirements. The results show that the reasonable arrangement of the baffle and static mixer can improve the uniformity of the flow field without causing excessive pressure loss. The present work has reference value for the optimization of the on-site SCR flow field retrofit.

关键词(KeyWords)： SCR脱硝;流场优化;导流板;氨氮物质的量比;静态混合器
SCR-DeNO_x;flow field optimization;baffle;ammonia-nitrogen molar ratio;static mixer

Abstract:

Keywords:

基金项目(Foundation): 国家重点研发计划资助项目(2019YFE0109700);; 广州市科技计划重点资助项目(201904020017)

作者(Authors): 黄俊;李兴磊;阮斌;罗圣;卢志民;姚顺春;
HUANG Jun;LI Xinglei;RUAN Bin;LUO Sheng;LU Zhimin;YAO Shunchun;Guangzhou Zhujiang Electric Power Co.,Ltd.;School of Electric Power,South China University of Technology;Guangdong Province Key Laboratory of Efficient and Clean Energy Utilization;Guangdong Province Engineering Research Center of High Efficiency and Low Pollution Energy Conversion;

DOI: 10.13226/j.issn.1006-6772.21061004

参考文献(References)：

• [1] 叶福南，姚顺春，陈耀荣，等.NOx浓度分布在线监测系统研发及应用[J].广东电力，2019,32(7):29-36.YE Funan,YAO Shunchun,CHEN Yaorong,et al.Development and application of online monitoring system for NOx concentration distribution [J].Guangdong Electric Power,2019,32(7):29-36.
• [2] 王珊.“十四五”如何推进超低排放?[N].中国环境报，2021-04-30(5).
• [3] 赵宗让.电厂锅炉SCR烟气脱硝系统设计优化[J].中国电力，2005(11):69-74.ZHAO Zongrang.Design optimization of SCR system for coal-fired boilers [J].Electric Power,2005(11):69-74.
• [4] 秦天牧，林道鸿，杨婷婷，等.SCR烟气脱硝系统动态建模方法比较[J].中国电机工程学报，2017,37(10):2913-2919.QIN Tianmu,LIN Daohong,YANG Tingting,et al.Comparative study on dynamic modeling of SCR denitration system[J].Proceedings of the CSEE,2017,37(10):2913-2919.
• [5] 于玉真，李伟亮，王绍龙，等.SCR脱硝系统流道均流装置数值模拟与优化[J].中国电机工程学报，2018,38(24):7304-7313.YU Yuzhen,LI Weiliang,WANG Shaolong,et al.Numerical simulation and optimization of SCR deNOx system flow channel flow-equalizing equipment[J].Proceedings of the CSEE,2018,38(24):7304-7313.
• [6] 马英利，高凤雨，贾广如，等.SCR脱硝催化剂的发展、应用及其成型工艺综述[J].现代化工，2019,39(8):33-37.MA Yingli,GAO Fengyu,JIA Guangru,et al.Overview on development,application and manufacturing of SCR catalysts for De-NOx[J].Modern Chemical Industry,2019,39(8):33-37.
• [7] 凌忠钱，曾宪阳，胡善涛，等.电站锅炉 SCR 烟气脱硝系统优化数值模拟[J] 动力工程学报，2014,34(1):50-56.LING Zhongqian,ZENG Xianyang,HU Shantao,et al.Numerical simulation on optimization of SCR denitrification system for coal-fired boilers [J].Journal of Chinese Society of Power Engineering,2014,34(1):50-56.
• [8] 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.
• [9] 杨超，张杰群，郭婷婷，等.SCR 烟气脱硝装置烟气流场数值模拟[J].东北电力大学学报，2012,32(1):66-70.YANG Chao,ZHANG Jiequn,GUO Tingting,et al.Numerical simulation of the flow field in a SCR system[J].Journal of Northeast Dianli University,2012,32(1):66-70.
• [10] 焦坤灵，陈向阳，别璇，等.SCR脱硝副产物硫酸氢铵特性研究：现状及发展[J].洁净煤技术，2021,27(1):108-124.JIAO Kunling,CHEN Xiangyang,BIE Xuan,et al.Status and development for characteristic of ammonium bisulfate as a by-product of SCR denitrification[J].Clean Coal Technology,2021,27(1):108-124.
• [11] 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.Advances in ammonia injection and mixing device of SCR-DeNOx system[J].Chemical Industry and Engineering Progress,2015,34(12):4151-4157.
• [12] 董陈，乔海勇，牛国平，等.某600 MW机组SCR烟气脱硝装置优化设计[J].热力发电，2014(12):99-104.DONG Chen,QIAO Haiyong,NIU Guoping,et al.Optimization design of SCR flue gas denitrification device for a 600 MW unit[J].Thermal Power Generation,2014(12):99-104.
• [13] 李壮扬，苏乐春，宋子健，等.660 MW燃煤机组SCR流场模拟优化与喷氨优化运行[J].洁净煤技术，2017,23(4):47-52,11.LI Zhuangyang,SU Lechun,SONG Zijian,et al.Optimization of flow and ammonia injection by numerical of SCR for a 660 MW coal-fired unit[J].Clean Coal Technology,2017,23(4):47-52,11.
• [14] WANG Shuqin,WANG Jing,WANG Xin.The simulation and optimization of flow field in the low temperature SCR reactor[J].IOP Conference Series:Earth and Environmental Science,2021,719(4):042024.
• [15] ZENG Haojun,YUAN Jingqi,WANG Jingcheng.Optimal design of a tower type SCR-deNOx facility for a 1 000 MW coal-fired power plant based on CFD simulation and FMT validation[J].Applied Sciences,2019,9(5):1012.
• [16] 李开拓.660 MW超超临界锅炉SCR数值模拟计算及导流板优化[J].技术与市场，2021,28(1):28-29,32.LI Kaituo.660 MW ultra-supercritical boiler SCR numerical simulation calculation and baffle optimization [J].Technology and Market,2021,28(1):28-29,32.
• [17] 吕太，赵学葵，王潜.燃煤机组SCR脱硝系统氨氮混合优化[J].热力发电，2016,45(7):13-20,26.LYU Tai,ZHAO Xuekui,WANG Qian.NH3-NOx mixture optimization for SCR denitrification system in a coal-fired unit[J].Thermal Power Generation,2016,45(7):13-20,26.
• [18] 王海川，曾祥浩，廖艳芬，等.SCR系统流场优化数值模拟研究[J].洁净煤技术，2020,26(4):147-153.WANG Haichuan,ZENG Xianghao,LIAO Yanfen,et al.Study on the numerical simulation of now 6eld optimization in SCR system[J].Clean Coal Technology,2020,26(4):147-153.
• [19] 安恩科，张瑞，韩益帆，等.多相湍流燃烧数值模拟的网格无关性分析[J].锅炉技术，2018,49(6):54-58.AN Enke,ZHANG Rui,HAN Yifan,et al.Numercial simulation mesh independence of multi-phase turbulent combustion[J].Boiler Technology,2018,49(6):54-58.
• [20] 徐劲，陈鸿伟，尹立冰，等.600 MW燃煤锅炉SCR脱硝系统流场数值模拟与优化设计[J].区域供热，2016(5):9-16.XU Jin,CHEN Hongwei,YIN Libing,et al.Numerical simulation and optimization design of flow field in SCR denitration system of 600 MW coal-fired boiler[J].District Heating,2016(5):9-16.
• [21] 梁玉超，胡满银，李媛，等.SCR反应器导流板及喷氨面的优化设计[J].热力发电，2012,41(9):103-105,109.LIANG Yuchao,HU Manyin,LI Yuan,et al.Optimization of deflector and spray ammonia in SCR reactor[J].Thermal Power Generation,2012,41(9):103-105,109.
• [22] 樊庆锌，王明轩，关心，等.某燃煤电厂300 MW机组SCR烟气脱硝装置结构优化[J].化工进展，2014(10):2806-2814.FAN Qingxin,WANG Mingxuan,GUAN Xin,et al.Optimal design of a SCR-DeNOx system for a 300 MW coal-fired power plant[J].Chemical Industry and Engineering Progress,2014(10):2806-2814.
• [23] 余廷芳，李俊，曾过房，等.火电厂SCR烟气脱硝装置的模拟优化[J].南昌大学学报(工科版),2014,36(2):113-117,132.YU Tingfang,LI Jun,ZENG Guofang,et al.Simulation and optimization for hue gas SCR reactor of thermal power units[J].Journal of Nanchang University (Engineering Science Edition),2014,36(2):113-117,132.
• [24] 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.燃煤烟气脱硝装备运行效果评价技术要求：GB/T 34340—2017[S].北京：中国标准出版社，2017.