Exposure, Epidemiology, and Risk Program, Department of Environmental Health, Harvard School of Public Health , 401 Park Drive, Landmark Center West Room 417, Boston, Massachusetts 02115, United States.
Environ Sci Technol. 2014;48(5):2870-6. doi: 10.1021/es404502x. Epub 2014 Feb 14.
We removed particulate matter (PM) emitted from a subway tunnel using magnetic filters. A magnetic filter system was installed on the top of a ventilation opening. Magnetic field density was increased by increasing the number of permanent magnet layers to determine PM removal characteristics. Moreover, the fan's frequency was adjusted from 30 to 60 Hz to investigate the effect of wind velocity on PM removal efficiency. As a result, PM removal efficiency increased as the number of magnetic filters or fan frequency increased. We obtained maximum removal efficiency of PM10 (52%), PM2.5 (46%), and PM1 (38%) at a 60 Hz fan frequency using double magnetic filters. We also found that the stability of the PM removal efficiency by the double filter (RSD, 3.2-5.8%) was higher than that by a single filter (10.9-24.5%) at all fan operating conditions.
我们使用磁性过滤器去除地铁隧道排放的颗粒物（PM）。在通风口的顶部安装了一个磁性过滤器系统。通过增加永磁体层的数量来增加磁场密度，以确定 PM 去除特性。此外，还调整了风扇的频率从 30 到 60 Hz，以研究风速对 PM 去除效率的影响。结果表明，随着磁性过滤器数量或风扇频率的增加，PM 去除效率也随之增加。在使用双磁过滤器时，我们在 60 Hz 风扇频率下获得了 PM10（52%）、PM2.5（46%）和 PM1（38%）的最大去除效率。我们还发现，在所有风扇运行条件下，双过滤器（RSD，3.2-5.8%）的 PM 去除效率稳定性均高于单过滤器（10.9-24.5%）。
