不均匀喷氨的NO_(x)通量获取方法和喷氨格栅阻力特性  

NO_(x)Flux Acquisition and AIG Resistance Characteristics of Uneven Ammonia Injection Method

作　　者：尚天坤 黄诚[2] 陈宙 朱文彬[2] 范辰浩 王健 SHANG Tiankun;HUANG Cheng;CHEN Zhou;ZHU Wenbin;FAN Chenhao;WANG Jian(Shanghai Minghua Electric Power Technology Co.,Ltd.,Shanghai 200090,China;Shanghai Waigaoqiao Power Generation Co.,Ltd.,Shanghai 200129,China)

机构地区：[1]上海明华电力科技有限公司,上海200090 [2]上海外高桥发电有限责任公司,上海200129

出　　处：《锅炉技术》2024年第1期75-80,共6页Boiler Technology

摘　　要：不均匀喷氨的方法是根据喷氨格栅建立不同分区的NO_(x)通量,设计分区不同的喷氨量,而NO_(x)通量由两个参数即烟气流速和NO_(x)浓度决定,试验和数值模拟方法是获得这两个参数的重要手段。通过对比发现,数值模拟的边界条件在实际中难以确定,无法较好地模拟流速场,而试验是更优的一种方法。试验结果显示,不同负荷和煤种下,喷氨格栅截面的流速分布基本不变,某些区域始终高,某些区域始终低。同时得到NO_(x)浓度的不均匀系数相对于流速不均匀系数很小,且考虑喷氨截面到催化剂还有一段扩散距离,可以仅考虑主要影响因素即烟气流速对不均匀喷氨的喷氨量进行设计,该方法简单有效,在工程实际中应用效果较好。同时对喷氨支管的阻力特性进行了试验研究,利用多孔介质代替该区域可以极大简化数值模拟区域。The method of uneven ammonia injection designs the ammonia injection quantity of each zone according to the NO_(x)flux of different zones devided by the ammonia injection grid(AIG).And the NO_(x)flux is determined by two parameters:flue gas flow field and NO.concentration field.Test and numerical simulation are both important means to obtain these two factors.The boundary conditions of numerical simulation are difficult to get in practice so that flow field can not be simulated precisely while test is a better way.The test shows that under different loads and coal types,the velocity distribution of AIG section is basically unchanged which means some zones are always high and some are always low.The test also indicates the non-uniformity coefficient of NO_(x)distribution is much smaller than the flow rate and there is still a diffusion distance from AIG to the catalyst,the ammonia injection amount can be set only by the main influence factor namely the flue gas flow rate.This method is simple and effective,having good application effect in engineering practice.The resistance characteristics of ammonia injection branch pipe are experimentally studied.The numerical simulation domain would be greatly simplified by using porous media.

关 键 词：不均匀喷氨 NO_(x)通量 流速场 浓度场 喷氨格栅 

分 类 号：X701[环境科学与工程—环境工程]