超长滤袋局部加密对滤袋表面过滤风速分布的影响  

Effect of local densification of ultra-long filter bags on the distribution of filtration velocity on the surface of filter bags

作　　者：杨宏刚[1,2] 李津瑾 曹莹雪 李浩东 孟晓静[1,2] 丁筱雨 YANG Honggang;LI Jinjin;CAO Yingxue;LI Haodong;MENG Xiaojing;DING Xiaoyu(School of Resources and Engineering,Xi'an University of Architecture and Technology,Xi'an 710055,China;National Key Laboratory of Green Building,Xi'an University of Architecture and Technology,Xi'an 710055,China)

机构地区：[1]西安建筑科技大学资源工程学院,西安710055 [2]西安建筑科技大学绿色建筑全国重点实验室,西安710055

出　　处：《安全与环境学报》2024年第7期2641-2647,共7页Journal of Safety and Environment

基　　金：绿色建筑全国重点实验室自主研究课题(LSZZ202206);陕西省自然科学基础研究计划一般项目(2022JQ-406)。

摘　　要：针对超长滤袋表面过滤风速沿其轴向分布极为不均的问题,采用数值模拟方法探究了超长滤袋局部加密对滤袋表面过滤风速分布的影响,为提升超长滤袋袋式除尘器的过滤性能寻求解决方法。结果表明:当超长滤袋未进行局部加密时,滤袋表面过滤风速沿其轴向自上而下呈递减趋势,最大过滤风速高达3.18 m/min(设计过滤风速为1.0 m/min),对应过滤风速分布均匀性指数为0.122,过滤风速分布极不均匀,此时滤袋顶部受到高速气流的冲刷作用明显;当对超长滤袋顶部30%长度滤袋进行局部加密后,滤袋表面过滤风速分布均匀性得到显著提升;当局部加密孔隙率由85%降至60%时,滤袋表面过滤风速分布均匀性指数由0.037先增至0.518后降至0.434,对应除尘效率并不受影响;当局部加密孔隙率取值为65%时,滤袋表面最大过滤风速降至2.1 m/min,此时过滤风速分布均匀性指数达到最大值0.518。Aiming at the problem that the filtration velocity on the surface of the ultra-long filter bag is extremely unevenly distributed along its axial direction,a numerical simulation method is used to explore the influence of local densification of the ultra-long filter bag on the filtration velocity distribution to find a solution to improve the filtration performance of the ultra-long filter bag filter.Firstly,the characterization parameters of local encryption are determined by theoretical analysis,and then the specific simulation conditions are designed.Finally,the appropriate indexes are selected to evaluate the uniformity of filtration velocity distribution on the surface of the filter bag.The results show that when the ultra-long filter bag is not locally densified,the filtration velocity on the surface of the filter bag decreases from top to bottom along its axial direction.The maximum filtration velocity is as high as 3.18 m/min(the design filtration velocity is 1.0 m/min),and the corresponding filtration velocity distribution uniformity index is 0.122.The distribution of filtration velocity is extremely uneven.Besides,the top of the filter bag is scoured by high-speed airflow.When the 30%length of the filter bag at the top of the ultra-long filter bag is locally densified,the uniformity of the filtration velocity distribution on the surface of the filter bag is significantly improved.When the local densification porosity decreases from 85%to 60%,the uniformity index of filtration velocity distribution on the surface of the filter bag increases from 0.037 to 0.518 and then decreases to 0.434,and the corresponding dust removal efficiency is not affected.When the local densification porosity is 65%,the maximum filtration velocity on the surface of the filter bag is reduced to 2.1 m/min,and the uniformity index of the filtration velocity distribution reaches the maximum value of 0.518.

关 键 词：安全卫生工程技术 袋式除尘器 超长滤袋 局部加密 过滤风速 均匀性 

分 类 号：X513[环境科学与工程—环境工程]