10th International Aerosol Conference September 2 - September 7, 2018 America's Center Convention Complex St. Louis, Missouri, USA
Abstract View
Development of Hybrid Dust Collector Installed at the In-use Trains for Removing Aerosols in Underground Subway Tunnels
Sang-Hee Woo, SEUNG-BOK LEE, Jong Bum Kim, Jae-In Lee, Gwi-Nam Bae, Moon Se Hwang, Hwa Hyun Yoon, Hong Ryang Jang, Eunserb An, Korea Institute of Science and Technology
Abstract Number: 1301 Working Group: Control and Mitigation
Abstract Airborne particles, or aerosols in underground subway tunnels are mainly composed of metal compounds (Aarnio et al., 2005; Salma et al., 2007; Martins et al., 2016; Moreno et al., 2017), and they have hazardous health risk of passenger and subway workers (Cheng et al., 2012; Park et al., 2014). Therefore, the air quality in the underground subway tunnels should be improved. Generally, a cleaning vehicle or a ventilation system were used to remove dust on the rail ground during traveling or aerosols at the fixed location in underground tunnels, respectively. However, the cleaning vehicle is very slow to clean whole tunnel, and the ventilation system removes particulate matters only in certain areas. In this study, a hybrid dust collector using both an inertial dust collector and an electrostatic precipitator (ESP) in series for application at the in-use subway trains to remove airborne particles from the underground tunnel. Its field performance test was carried out by attaching it to a real subway train.
Two kinds of hybrid dust collectors have been developed. Model 1 has louver as the inertial dust collector for removing large aerosols and one-stage ESP without a fan, and model 2 has baffle and two-stage ESP with a fan. In both cases, EPS was the main component, and inertial dust collector was added to compensate for the disadvantages of the ESP. The each component of the hybrid dust collectors was optimized by wind tunnel experiments. Based on experimental and simulated results, the hybrid dust collectors were optimized to remove the highest weight of aerosols per hour.
After optimizing, the hybrid dust collectors were installed at the in-use train, and operated for 350 hours for 43 days. As a result, the weight of collected aerosols increased linearly with the operating time. Measured weight of collected aerosols was slightly higher than the prediction value based on wind tunnel experiment result, probably because the aerosol concentration at the bottom of the subway train must be higher than that measured at the height of platform. The hybrid dust collector was able to collect 20 to 40 mg of aerosols per 1 km travel distance, and it captured several hundred grams of aerosols during the field test period.