Rate of Sulfur Dioxide Removal Artificial Cloud Experiments Utilizing a Long Vertical Shaft
Source: Water, Air, and Soil Pollution, Volume 130, Numbers 1-4, August 2001 , pp. 325-330(6)
Removal of sulfur dioxide through the absorption into cloud droplets is the initial stage of acid rain formation. We studied this process by forming an artificial cloud with a spatial scale close to the real one. We used a vertical shaft of 430 m in length in an abandoned mine, and operating an electric fan placed at the top of the shaft, generated an updraft of about 1 m s^−1 of the air humidified by underground water. This produced an artificial cloud rising about 400m above the cloud base observed at a height of about 35 m from the bottom. At the bottom of the shaft, we emitted SO_2 gas into the air stream, and measured its concentration profile by an SO_2-meter loaded on an elevator going up and down in the shaft. From the slope of the observed decay curve, we evaluated the rate constant for the absorption to be 0.010 s^−1. This value was found to agree in order of magnitude with an estimate derived on the basis of the laminar film model for mass transfer.
Document Type: Regular paper
Affiliations: 1: National Institute for Environmental Studies, Tsukuba, 305-0053, Japan e-mail: firstname.lastname@example.org 2: National Institute for Environmental Studies, Tsukuba, 305-0053, Japan 3: Graduate School of Engineering, Hokkaido University, Sapporo, 060-8628, Japan 4: Faculty of Engineering, Toyo University, Kawagoe, 350-8585, Japan 5: Graduate School of Science, Hokkaido University, Sapporo, 060-0810, Japan 6: The Institute of Low Temperature Science, Hokkaido University, Sapporo, 060-0819, Japan 7: Faculty of Science and Engineering, Chuo University, Bunkyo-ku, Tokyo, 112-0003, Japan 8: Mitsui Construction Co., Chiba, 261-0023, Japan
Publication date: 2001-08-01