高炉出铁场“电改袋”技术研究与工程示范

20世纪,在炼铁生产过程中,高炉出铁场的除尘基本采用的是电除尘器技术。随着环境要求的提高,许多炼铁厂将电除尘改为布袋除尘——电改袋。"电改袋"通常要利用原有的电除尘器壳体,只改变其内部结构,从而也改变了原除尘器内气流流向。为了预测"电改袋"后各区域气流流向,文章基于CFX商用流体力学计算软件,对除尘器"电改袋"后的气流进行了速度场模拟。模拟研究结果表明:从前到后,各滤室上行风速逐渐增大。对于4滤室的袋式除尘器,第四滤室风量比第一滤室风速大3倍以上。为了克服风量不均衡问题,采用可调式斜向挡板风量分配新工艺,从而对提高袋式除尘器的收尘性能,指导"电改袋"的工程实践具有重要意义。

Study and Demonstration Project of Reconstructing Electrostatic Precipitator into Bag Filter in Iron Outlet of Blast Furnace

Electrostatic precipitator was used to treat smoke dust coming from iron outlet of blast furnace in last century. Many iron-refineries have reconstructed electrostatic precipitator into bag filter in order to enhance environment and reduce discharge of smoke dust recently. Air flow direction in the bag filter after electric reconstructed cloth will change since the external box was usually reused and only internal structure was reconstructed in electric reconstructed cloth. In order to predict air flow direction in bag filter and meet the need of rational draft flow distribution, CFX software was used to simulate velocity distribution of air flow. Results showed that the upward air speed in different filtering parts was different, the upward air speed of filtering part behind was higher than ahead. The upward air speed of the fourth filtering part was more than 3 times higher than of the first filtering part. In order to solve the problem of heterogeneous draft flow distribution, the adjustable sloping plank was used.