Enhancing the Fuel Value of Wood Pellets with the Addition of Lignin

Authors

  • Jason Stevens
  • Douglas J. Gardner

Keywords:

Wood pellets, Lignin, Kraft black liquor, Indulin AT, fuel value, moisture content

Abstract

Because of the increased cost of petroleum-based energy production, there is renewed interest in the use of wood for energy. In particular, residential heating using wood pellets has experienced a large increase during the last decade. Manufacturers of wood pellets are interested in producing high-quality, high fuel-value pellets. In this study, lignin was explored as an additive to wood to enhance pellet fuel value. Two types of lignin were examined in the production of wood pellets, Kraft black liquor and Indulin AT (IAT). Lignin was added to a softwood furnish and pellets were prepared on a commercial California Pellet Mill. The pellets were analyzed for fuel value, moisture content, and quality. Those prepared with IAT produced better quality pellets and had a higher fuel value than with Kraft black liquor. The Kraft black liquor pellets were soft and spongy and easily fell apart. A cost analysis indicates that lignin preparation will have a major impact on the feasibility of adding lignin to wood pellets to enhance fuel value.

References

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Published

2010-10-11

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Section

Research Contributions