• Search Research Projects
  • Search Researchers
  • How to Use
  1. Back to project page

1999 Fiscal Year Final Research Report Summary

Real Scale Experiment of Pollution and Modification of Cloud by using a Vertical Shaft.

Research Project

Project/Area Number 09450195
Research Category

Grant-in-Aid for Scientific Research (B)

Allocation TypeSingle-year Grants
Section一般
Research Field Civil and environmental engineering
Research InstitutionHokkaido University

Principal Investigator

OHTA Sachio  Hokkaido Univ., Grad. School of Eng. Pro., 大学院・工学研究科, 教授 (00100058)

Co-Investigator(Kenkyū-buntansha) FUKUYAMA Tsutomu  Natl. Inst. Envi. Sci., Head of Lab., 大気圏環境部, 室長(研究職) (90011642)
YAMAGATA Sadsamu  Hokkaido Univ., Grad. School of Eng., Inst., 大学院・工学研究科, 助手 (80220242)
MURAO Naoto  Hokkaido Univ., Grad. School of Eng., Asso. Pro., 大学院・工学研究科, 助教授 (00190869)
UTIYAMA Masahiro  Natl. Inst. Envir. Sci., Chief. Scientist, 大気圏環境部, 主任研究員 (20160294)
Project Period (FY) 1997 – 1999
Keywordsvertical shaft / cloud pollution / cloud modification / acidification to sulfate / cloud condensation nuclei / droplet size distribution / generation of particles / mineral particles
Research Abstract

The process of sulfur dioxide dissolution into cloud droplets and its successive oxidation to sulfate were studied in an artificial cloud experimental system in a vertical shaft in Kamaishi mining company, Iwate prefecture. Sulfur compounds in droplets, aerosols and gas were collected by serial samplers at several heights. The concentrations of sulfur compounds at each height indicate that the released sulfur dioxide at the bottom of the shaft was absorbed by cloud droplets, but the oxidation rate to sulfate was slow which may be due to the absence of light and oxidants in the shaft.
Sodium chloride and sodium hydrogensulfite particles were generated by humifier and injected into the base of shaft. Modal diameter of the particles is 0.1〜0.5μm. Without the particle injection, modal diameter of cloud droplets was 7 μm. With the particle injection, modal diameter of cloud droplets did not change, but the size distribution widened out to larger diameter.
By using eletron microscope with X ray analyzer, we found that more than 50 % of the droplets, which arrived at top of the shaft, contained chemical species of the injected particles. But, the other particles cintained calsium carbonate. It shows that calsium carbonate particles or mineral particles coated with calsium carbonate on the surface may act as condensation nuclei in the atmosphere.

  • Research Products

    (1 results)

All Other

All Publications (1 results)

  • [Publications] Yamagata, S., Baba, S., Murao, N., Ohta, S, Fukuyama, T., Utiyama. M., Yamada, T., Fujiyoshi. Y., Harimaya, T. and Inage, M.: "Real scale experiment of sulfur dioxide dissolution into cloud droplets generated in artificial cloud experimental system (ACE)."Journal of Global Environment Engineering. Vol.4. 53-63 (1998)

    • Description
      「研究成果報告書概要(欧文)」より

URL: 

Published: 2001-10-23  

Information User Guide FAQ News Terms of Use Attribution of KAKENHI

Powered by NII kakenhi