Ethanol Production from Spent Sulfite Liquor Fortified by Hydrolysis of Pulp Mill Primary Clarifier Sludge

  • John W. Moritz
  • J. B. Duff Sheldon
Part of the ABAB Symposium book series (ABAB, volume 57/58)

Abstract

Some low-yield sulfite pulping operations ferment spent sulfite liquor (SSL) to remove biochemical oxygen demand associated with dissolved sugars while at the same time generating ethanol as a salable product. Simultaneous saccharification and fermentation (SSF) of primary clarifier sludge in a medium of SSL was proposed as a means of reducing the amount of sludge to be disposed of while at the same time increasing ethanol productivity. In this article, the option of fortifying existing SSL fermenting processes with the sugars produced via in situ enzymatic hydrolysis of sulfite primary clarifier sludge (PCS) has been explored. In 100% SSL PCS hydrolysis rates as high as 3.4 g/(L•h) were observed at an initial enzyme loading of 10 filter paper units (FPU)/g PCS. To reduce the deleterious effects of glucose inhibition, single-stage SSF was carried out using cellulase enzymes and Saccharomyces cerevisiae. The production rate of ethanol in SSL was increased by as much as 25% through the SSF process.

Index Entries

SSF primary clarifier sludge ethanol production 

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References

  1. 1.
    Coughlan, M. P. (1992) Bioresource Technol. 39, 107–115.CrossRefGoogle Scholar
  2. 2.
    Ladisch, M. R. and Svarczkopf, J. A. (1991) Bioresource Technol. 36, 83–95.CrossRefGoogle Scholar
  3. 3.
    Lynd, L. R., Cushman, J. H., Nichols, R. J., and Wyman, C. E. (1991) Science 251, 1318–1322.CrossRefGoogle Scholar
  4. 4.
    Vallander, L. and Eriksson, K.-E. L. (1990), Adv. Biochem. Eng. /Biotechnol. 42, 63–95.CrossRefGoogle Scholar
  5. 5.
    Duff, S. J. B., Moritz, J. W., and Andersen, K. L. (1994) Can. J. Chem. Eng. 72, 1013–1020.CrossRefGoogle Scholar
  6. 6.
    Grohmann, K. (1993), in Bioconversion of Forest and Agricultural Residues, Saddler, J. N., ed., Biotechnology in Agriculture, No. 9., CAB International, Wallingford, UK, pp. 183–209.Google Scholar
  7. 7.
    Philippidis, G. P., Smith, T. K., and Wyman, C. E. (1993) Biotechnol. Bioeng. 41, 846–853.CrossRefGoogle Scholar
  8. 8.
    South, C. R. and Lynd, L. R. (1994) Appl. Biochem. Biotechnol. 45, 467–481.CrossRefGoogle Scholar
  9. 9.
    Katzen, R. and Fowler, D. E. (1994) Appl. Biochem. Biotechnol. 45, 697–707.CrossRefGoogle Scholar
  10. 10.
    Aiba, S., Humphrey, A. E., and Millis, N. F. (1973) Biochemical Engineering, 2nd ed., Academic, New York.Google Scholar
  11. 11.
    Miller, G. L. (1959) Anal. Chem. 31, 420–428.Google Scholar
  12. 12.
    Duff, S. J. B., Moritz, J. W., and Casavant, T. E. (1995) Biotechnol. Bioeng. 45, 239–244.CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media New York 1996

Authors and Affiliations

  • John W. Moritz
    • 1
  • J. B. Duff Sheldon
    • 1
  1. 1.UBC Pulp and Paper Centre and Department of Chemical EngineeringUniversity of British ColumbiaVancouverCanada

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