某燃煤电厂锅炉除尘器“电改袋”后问题的数值模拟分析  

The numerical simulation analysis of problems after ESP transformed into bag filter in a coal-fired power plant boiler dust collector

作　　者：王明星[1] 沈恒根[1] 周睿[1] 丁毅 史德明 夏勇军 李通 

机构地区：[1]东华大学环境科学与工程学院,上海201620 [2]马鞍山钢铁集团有限公司,安徽马鞍山243003

出　　处：《电力科技与环保》2013年第3期18-21,共4页Electric Power Technology and Environmental Protection

摘　　要：针对某燃煤电厂除尘器"电改袋"后运行中出现的设备阻力较高、滤袋破损、收尘灰斗灰量不均匀问题进行分析。采用数值模拟分析方法对除尘器内部的气流组织进行模拟试验研究,结合现场实际设备建立了物理模型,对除尘空间颗粒物沉积进行了理论分析,结果表明进入除尘器的颗粒物(200μm以下)沉降速度低于1.5m/s。把含尘气体近似为气相气流,采用Realizableκ-ε紊流模型进行该袋式除尘器除尘空间流场计算,结果表明除尘区中间气流平均上升速度达到1.0m/s,在该上升气流作用下大部分颗粒物难以自然沉积是造成阻力增大的主要原因之一;采用长流程设计除尘空间会造成袋底下部空间的气流速度较大,前大后小,平均相差达到4倍左右,造成滤袋收尘量后移,它是造成滤袋破损和阻力升高的主要原因;各仓室流量分配相差11%～13%及各仓室滤袋流量分配不均容易造成局部滤袋破损几率增高。The problems which are high resistance, broken filter bags, uneven amount of ash hopper dust collection in a coal - fired power plants after ESP transformed into bag filter are analyzed. Using numerical simulation analysis method to study the airflow organization in the dust collector and making theoretical analysis on particulate matters in dust collection space. It found that the dusts＇settling velocity less than Ira/s, these particle matters get into dust collector and their size less than 200μm. Useing Realizable k -ε turbulence model to calculate the flow filed in the bag filter,the results show that the average rising speed of airflow reaches 1m/s in the middle of bag filter,most of particles in the updraft are difficult to naturally fall,which is one of the main reasons for resistance increases. It will cause high speed under the bag filter if designed the dust collection space into long process,the speed will high in front of and low in back,a difference of about up to 4 times,which causes the amount of ash collection move backward ;The filter bags become easy to damage becsuse of difference of 11 % 13% in flow distribution in every chamber and the uneven flow distribution in a chamber.

关 键 词：燃煤电厂 “电改袋”除尘器 速度分布 气流均匀性 

分 类 号：X701.2[环境科学与工程—环境工程]