混合器对SCR脱硝系统内多相多组分流动特性影响的数值研究Numerical Study on Gas-Solid Phase Flow and Species Concentration Performance of Static Mixers with an SCR-DeNO_x System
雷鉴琦,王晓波,吕秀川,闫俊刚,严冰清
Lei Jianqi,Wang Xiaobo,Lv Xiuchuan,Yan Jungang,Yan Bingqing
摘要(Abstract):
为了从流动特性、烟尘运动、氨氮混合等方面综合分析对比SCR脱硝系统内圆盘、管式、V型、三角翼混合器的性能,利用数值模拟方法对SCR脱硝系统内两相流动、组分输运及流阻特性进行了数值计算。计算结果表明:与未安装混合器方案相比,脱硝入口至催化剂上方截面流动阻力增加了9.566%~24.051%,在促进氨氮混合方面,圆盘混合器性能最优,氨氮比均匀性相对提高44.487 9%。热态气固两相流动模拟结果显示,各类型混合器均能提高催化剂入口截面烟尘浓度的均匀性,但在相同迎风面积条件下,圆盘混合器会引起的流动阻力最大。定义了烟尘浓度C_v、氨氮比C_v与压降Δp归一化处理后的差值为混合器性能的衡量标准,圆盘混合器的综合性能最优。
In order to comprehensively analyze the performance of disk,pipe,V-shape and delta wing mixers in terms of flow characteristics,motion of flue gas,mixing of NH_3/NO_x gas,etc.in the SCR de-nitration system,numerical simulation was carried out on the gas-solid phase flow,species transport,flow resistance characteristics of the mixers using the numerical simulation method.The results show that,compared with the original scheme without the mixed installed,the flow resistance on the section of the part from de-nitration inlet to top of the catalyst was increased by 9.566%~24.051%,the disc mixer had the best performance in terms of ammonia and nitrogen mixing,and homogeneity of NH_3/NO_x ratio was relatively improved by 44.487 9%.Numerical simulation results of two-phase flow in hot state show that all types of mixers can improve homogeneity of the particle mass concentration at catalyst inlet,but disk mixers cause the greatest flow resistance under the condition of equal windward area.The difference in ash concentration,ammonia-nitrogen ratio and pressure drop Δp after normalization was defined as the criterion to measure the performance of the mixers,and the disk static mixers has the comprehensive optimal performance.
关键词(KeyWords):
混合器;SCR脱硝;数值模拟;两相流动
static mixer;SCR De-nitration;numerical simulation;two-phase flow
基金项目(Foundation): 吉林省科技发展计划资助项目(20180201001SF);; 中国大唐集团公司重大科技项目(13.12)
作者(Author):
雷鉴琦,王晓波,吕秀川,闫俊刚,严冰清
Lei Jianqi,Wang Xiaobo,Lv Xiuchuan,Yan Jungang,Yan Bingqing
参考文献(References):
- [1] 中国电力企业联合会.中国电力行业年度发展报告2018[M].北京:中国电力出版社,2018.
- [2] 安敬学,王磊,秦淇,等.SCR脱硝系统催化剂磨损机理分析与治理[J].热力发电,2015,44(12):119-124.
- [3] 安敬学,王磊,秦淇,等.电站锅炉脱硝系统催化剂磨损数值模拟[J].锅炉技术,2016,47(2):32-38.
- [4] 裴煜坤.SCR烟气脱硝系统喷氨混合装置优化研究[D].杭州:浙江大学,2013.
- [5] 罗志,许剑,李斌,等.燃用高沾污性煤质锅炉SCR脱硝流场优化[J].热力发电,2018,47(12):111-117.
- [6] 潘晓慧,马春元,崔琳.两相均流板对弯管中气固两相运动分布特征的影响[J].化工学报,2016,67(6):2308-2317.
- [7] 雷鉴琦.降低燃煤机组SCR脱硝系统催化剂磨损的流场优化[J].中国电力,2018,51(7):152-156.
- [8] 周英贵,金保昇.基于非均匀入口条件SCR系统气固相组分的分布特性优化[J].环境工程学报,2017,11(1):421-426.
- [9] 张翠珍,赵学葵.大型燃煤机组SCR脱硝系统优化[J].环境工程学报,2015,9(12):5997-6004.
- [10] 罗志,牛国平,王晓冰,等.分区混合动态喷氨技术工程应用[J].热力发电,2018,47(8):125-131.
- [11] 洪文鹏,兰江.SCR脱硝系统静态混合器数值模拟[J].锅炉技术,2014,45(3):68-73.
- [12] 黄庆华,宋丽云,何洪.一种SCR脱硝装置喷氨混合系统的结构优化设计[J].环境工程,2016,34(215):59-64.
- [13] 叶侠丰,丁红蕾,潘卫国,等.圆管束与椭圆管束换热、磨损及积灰特性的数值研究[J].中国电机工程学报,2018,38(11):3289-3294.
- [14] 王宇,何琪,于飞,等.组合弯头内气固两相流动磨损特性的数值模拟与结构优化[J].中国电机工程学报,2018,38(3):832-839.
- [15] Xu Yuanyuan,Zhang Yan,Liu Fengna,et al.CFD analysis on the catalyst layer breakage failure of an SCR-deNOx system for a 350MW coal-fired power-plant[J].Computers and Chemical Engineering,2014,69:119-126.
- [16] Risio B,Han X,Hilber M,et al.Industrial scale assessment of the predictive quality of a 3D-CFD model for SCR de-NOx catalysts[J].VGB Powertech,2012,92(10):74-79.
- [17] 肖雨亭,徐莉,贾曼,等.蜂窝式脱硝催化剂在烟气中磨损行为的模拟研究[J].中国电力,2012,45(12):96-98.
- [18] 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.
- [19] 庄柯,姚杰,吴碧君,等.脱硝反应器内烟气与飞灰分布差异的数值模拟[J].中国电力,2018,51(2):137-142.