Commoditization of wet and high ash biomass: wet torrefaction—a review

  • Krzysztof Jerzy Mościcki Wrocław University of Technology
  • Łukasz Niedźwiecki University of Leeds
  • Paweł Owczarek University of Twente
  • Mateusz Wnukowski Wrocław University of Technology


Biomass is a non-intermittent energy source, which can play an important role in grid-based energy systems, since they needsome non-intermittent sources in order to balance the variability of intermittent sources as wind and solar energy. Currently,this role is played mostly by fossil fuels, mainly because of the bulk size of a single source. Higher variability and lowerenergy concentration, among with some properties of biomass, are obstacles that prevent it from fully becoming a commodity.There are processes, such as dry torrefaction and hydrothermal carbonization (HTC) that could potentially help in terms ofmaking biomass a tradable commodity, as is the case with fossil fuels. HTC, also known as wet torrefaction, might help solveproblems that dry torrefaction is incapable of solving. These obstacles are, namely: high ash content, slagging and foulingproperties of biomass (along with corrosion). Also the high moisture content of some types of biomass poses a problem,since they usually require substantial amounts of heat for drying. This paper reviews current knowledge about a processthat could possibly transform problematic types of biomass into tradable commodities and compares it with other processesoffering similar outcomes.


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How to Cite
MOŚCICKI, Krzysztof Jerzy et al. Commoditization of wet and high ash biomass: wet torrefaction—a review. Journal of Power Technologies, [S.l.], v. 97, n. 4, p. 354–369, jan. 2016. ISSN 2083-4195. Available at: <>. Date accessed: 23 july 2024.
Combustion and Fuel Processing


commoditization of biomass, torrefaction, hydrothermal carbonization

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