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Environmental Chemistry Letters

, Volume 4, Issue 1, pp 37–40 | Cite as

Green liquor dregs as an alternative neutralizing agent at a pulp mill

  • R. PöykiöEmail author
  • H. Nurmesniemi
  • T. Kuokkanen
  • P. Perämäki
Original Paper

Abstract

Green liquor dregs is the biggest waste fraction at sulphate pulp mills. It is commonly landfilled. Here we demonstrate that the utilization of green liquor dregs as a neutralizing agent for acidic wastewaters is a potential alternative and an environmentally friendly method in contrast to its landfill disposal. The liming effect value of 39.6% for green liquor dregs, expressed as Ca equivalent, is similar to the liming effect value of 38% of a commercial limestone product. In addition, the pH value of 10.7 indicates a strong liming effect.

Keywords

Green liquor dregs Causticizing Waste Pulp mill Neutralizing agent Metals 

Notes

Acknowledgements

The authors wish to thank the technical staff of Suomen Ympäristöpalvelu Oy, especially M.Sc. Ilkka Välimäki, under whose supervision all the chemical analyses were performed.

References

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Copyright information

© Springer-Verlag 2005

Authors and Affiliations

  • R. Pöykiö
    • 1
    Email author
  • H. Nurmesniemi
    • 2
  • T. Kuokkanen
    • 3
  • P. Perämäki
    • 3
  1. 1.The Town Planning and Building CommitteeThe Environmental Research Division, City of KemiKemiFinland
  2. 2.Stora Enso OyjKemiFinland
  3. 3.Department of ChemistryUniversity of OuluOuluFinland

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