Applied Biochemistry and Biotechnology

, Volume 61, Issue 3, pp 339–349 | Cite as

Desulfurization of pittsburgh coal by microbial column flotation

  • Naoya Ohmura
  • Hiroshi Saiki
Original Articles


Microbial column flotation usingThiobacillus ferrooxidans was applied for desulfurization of Pittsburgh coal of CWM (Coal-Water Mixture) size between 38 μm and 75 μm. The coal contained ferrous ion which would interfere separation of pyrite from coal by microbial flotation. The wash-out of ferrous ion with 0.5N HC1 solution enabled pyrite removal from coal. The coal was divided into two parts, the small-size coal between 38 μm and 53 μm, and the large-size coal between 53 μm and 75 μm. The pyritic sulfur content was decreased from 2.88% of the feed coal to 0.98% of the product coal for the largesize coal and from 2.77% of the feed coal to 1.12% of the product coal for the small-size coal by microbial flotation. The decrease was based on removal of liberated pyrite particles (between 20 μm and 70 μm). However, the fine particles (less than 20 μm) could not be removed even though the pyrite particles were liberated from coal particles. The microbial column flotation was more effective for desulfurization of the large liberated pyrite particle than that of the small. It was not effective for desulfurization of the locked pyrite particles that were buried in coal particles. Both the pyrite liberation from coal and its particle size are important factors for the pyrite removal by microbial column flotation.

Index entries

Thiobacillus ferrooxidans flotation coal pyrite desulfurization 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. 1.
    Bastille, A. (1981),Natl. Georgr. Nov., 652–680.Google Scholar
  2. 2.
    William, E. P. E. and Steven, A. L. (1982),Power. May, 71–76.Google Scholar
  3. 3.
    Karlsson, H. T., Holst, O., Larsson, L., Mattiasson, B., Nilsson, B., and Ericsson, I. (1987),Int. Chem. Symp. Ser. 107, 25–32.Google Scholar
  4. 4.
    Attia, Y. A. (1990),Resour. Conserv. Recycl. 3, 169–175.CrossRefGoogle Scholar
  5. 5.
    Ohmura, N., Kitamura, K., and Hiroshi, S. (1993),Biotechnol. Bioeng. 41, 671–676.CrossRefGoogle Scholar
  6. 6.
    Ohmura, N., Kitamura, K., and Hiroshi, S. (1993),Appl. Environ. Microbiol. 59(12), 4044–4050.Google Scholar
  7. 7.
    Atkins, A. S., Bridgewood, E. W., and Davis, A. J. (1987),Coal Prep. 5, 1–13.CrossRefGoogle Scholar
  8. 8.
    Townsley, C. C. and Atkins, A. S. (1986), Process.Biochem. Dec, 188–191.Google Scholar
  9. 9.
    Townsley, C. C., Atkins, A. S., and Davis, A. J. (1987),Biotechnol. Bioeng. 30, 1–8.CrossRefGoogle Scholar
  10. 10.
    Ohmura, N. and Hiroshi, S. (1994),Biotechnol. Bioeng. 44, 125–131.CrossRefGoogle Scholar
  11. 11.
    Zeky, M. E. L. and Attia, Y. A. (1987),Coal Prep. 5, 15–37.CrossRefGoogle Scholar
  12. 12.
    Silverman, M. P. and Lundgren, D. G. (1959),J. Bacteriol. 77, 642–647.CrossRefGoogle Scholar

Copyright information

© Humana Press Inc. 1997

Authors and Affiliations

  • Naoya Ohmura
    • 1
  • Hiroshi Saiki
    • 1
  1. 1.Department of Biotechnology, Abiko Research LaboratoryCentral Research Institute of Electric Power IndustryAbikoshi, ChibaJapan

Personalised recommendations