IDEAS home Printed from https://ideas.repec.org/a/gam/jeners/v18y2025i13p3464-d1692258.html
   My bibliography  Save this article

Analysis of Mechanical Durability, Hydrophobicity, Pyrolysis and Combustion Properties of Solid Biofuel Pellets Made from Mildly Torrefied Biomass

Author

Listed:
  • Kanageswari Singara veloo

    (Biomass and Bioenergy Research Group, Department of Chemical and Biological Engineering, University of British Columbia, Vancouver, BC V6T 1Z3, Canada)

  • Anthony Lau

    (Biomass and Bioenergy Research Group, Department of Chemical and Biological Engineering, University of British Columbia, Vancouver, BC V6T 1Z3, Canada)

  • Shahab Sokhansanj

    (Biomass and Bioenergy Research Group, Department of Chemical and Biological Engineering, University of British Columbia, Vancouver, BC V6T 1Z3, Canada)

Abstract

The production of solid biofuels from torrefied biomass holds significant potential for renewable energy applications. Durable pellet formation from severely torrefied biomass is hindered by the loss of natural binding properties, yet studies on mild torrefaction that preserves sufficient binding capacity for pellet production without external binders or changes to die conditions remain scarce. This paper investigated the production of fuel pellets from torrefied biomass without using external binders or adjusting pelletization parameters. Experiments were conducted using a mild torrefaction temperature (230 °C and 250 °C) and shorter residence time (10, 15, and 30 min). The torrefied materials were then subjected to pelletization using a single-pellet press; and the influence of torrefaction on the mechanical durability, hydrophobicity, and fuel characteristics of the pellets was examined. Results indicated that the mass loss ranging from 10 to 20% among the mild torrefaction treatments was less than the typical extent of mass loss due to severe torrefaction. Pellets made from torrefied biomass (torrefied pellets) had improvement in the hydrophobicity (moisture resistance) when compared to pellets made from untreated biomass (untreated pellets). Improved hydrophobicity is important for storage and transportation of pellets that are exposed to humid environmental conditions, as it reduces the risk of pellet degradation and spoilage. Thermogravimetric analysis of the pyrolysis and combustion behaviour of torrefied pellets indicated the improvement of fuel characteristics in terms of a much higher comprehensive pyrolysis index and greater thermal stability compared to untreated pellets, as evidenced by the prolonged burnout time and reduced combustion characteristics index. Residence time had a more significant impact on pellet durability than temperature, but the durability of the torrefied pellets was lower than that of the untreated pellets. Further research is required to explore the feasibility of producing binder-free durable pellets under mild torrefaction conditions. Overall, the study demonstrated that mild torrefaction could enhance the fuel quality and moisture resistance of biomass pellets, offering promising advantages for energy applications, despite some trade-offs in mechanical durability.

Suggested Citation

  • Kanageswari Singara veloo & Anthony Lau & Shahab Sokhansanj, 2025. "Analysis of Mechanical Durability, Hydrophobicity, Pyrolysis and Combustion Properties of Solid Biofuel Pellets Made from Mildly Torrefied Biomass," Energies, MDPI, vol. 18(13), pages 1-18, July.
    • Handle: RePEc:gam:jeners:v:18:y:2025:i:13:p:3464-:d:1692258
    as

    Download full text from publisher

    File URL: https://www.mdpi.com/1996-1073/18/13/3464/pdf
    Download Restriction: no
    File URL: https://www.mdpi.com/1996-1073/18/13/3464/
    Download Restriction: no
    ---><---

    References listed on IDEAS

    as
    1. Zhu, Guangyue & Wen, Chang & Liu, Tianyu & Xu, Minghou & Ling, Peipei & Wen, Wuhao & Li, Ruonan, 2024. "Combustion and co-combustion of biochar: Combustion performance and pollutant emissions," Applied Energy, Elsevier, vol. 376(PA).
    2. Wang, Shurong & Dai, Gongxin & Ru, Bin & Zhao, Yuan & Wang, Xiaoliu & Xiao, Gang & Luo, Zhongyang, 2017. "Influence of torrefaction on the characteristics and pyrolysis behavior of cellulose," Energy, Elsevier, vol. 120(C), pages 864-871.
    3. Larsson, Sylvia H. & Rudolfsson, Magnus & Nordwaeger, Martin & Olofsson, Ingemar & Samuelsson, Robert, 2013. "Effects of moisture content, torrefaction temperature, and die temperature in pilot scale pelletizing of torrefied Norway spruce," Applied Energy, Elsevier, vol. 102(C), pages 827-832.
    4. Bajwa, Dilpreet S. & Peterson, Tyler & Sharma, Neeta & Shojaeiarani, Jamileh & Bajwa, Sreekala G., 2018. "A review of densified solid biomass for energy production," Renewable and Sustainable Energy Reviews, Elsevier, vol. 96(C), pages 296-305.
    5. Lu, Ke-Miao & Lee, Wen-Jhy & Chen, Wei-Hsin & Lin, Ta-Chang, 2013. "Thermogravimetric analysis and kinetics of co-pyrolysis of raw/torrefied wood and coal blends," Applied Energy, Elsevier, vol. 105(C), pages 57-65.
    6. James W. Butler & William Skrivan & Samira Lotfi, 2023. "Identification of Optimal Binders for Torrefied Biomass Pellets," Energies, MDPI, vol. 16(8), pages 1-23, April.
    7. Manouchehrinejad, Maryam & Bilek, E.M. Ted & Mani, Sudhagar, 2021. "Techno-economic analysis of integrated torrefaction and pelletization systems to produce torrefied wood pellets," Renewable Energy, Elsevier, vol. 178(C), pages 483-493.
    8. Rudolfsson, Magnus & Borén, Eleonora & Pommer, Linda & Nordin, Anders & Lestander, Torbjörn A., 2017. "Combined effects of torrefaction and pelletization parameters on the quality of pellets produced from torrefied biomass," Applied Energy, Elsevier, vol. 191(C), pages 414-424.
    9. Peng, Jianghong & Bi, Xiaotao T. & Lim, C. Jim & Peng, Hanchao & Kim, Chang Soo & Jia, Dening & Zuo, Haibin, 2015. "Sawdust as an effective binder for making torrefied pellets," Applied Energy, Elsevier, vol. 157(C), pages 491-498.
    10. Junga, Robert & Pospolita, Janusz & Niemiec, Patrycja, 2020. "Combustion and grindability characteristics of palm kernel shells torrefied in a pilot-scale installation," Renewable Energy, Elsevier, vol. 147(P1), pages 1239-1250.
    11. Li, Hui & Liu, Xinhua & Legros, Robert & Bi, Xiaotao T. & Jim Lim, C. & Sokhansanj, Shahab, 2012. "Pelletization of torrefied sawdust and properties of torrefied pellets," Applied Energy, Elsevier, vol. 93(C), pages 680-685.
    Full references (including those not matched with items on IDEAS)

    Most related items

    These are the items that most often cite the same works as this one and are cited by the same works as this one.
    1. Mostafa, Mohamed E. & Hu, Song & Wang, Yi & Su, Sheng & Hu, Xun & Elsayed, Saad A. & Xiang, Jun, 2019. "The significance of pelletization operating conditions: An analysis of physical and mechanical characteristics as well as energy consumption of biomass pellets," Renewable and Sustainable Energy Reviews, Elsevier, vol. 105(C), pages 332-348.
    2. Rudolfsson, Magnus & Larsson, Sylvia H. & Lestander, Torbjörn A., 2017. "New tool for improved control of sub-process interactions in rotating ring die pelletizing of torrefied biomass," Applied Energy, Elsevier, vol. 190(C), pages 835-840.
    3. Yun, Huimin & Clift, Roland & Bi, Xiaotao, 2020. "Process simulation, techno-economic evaluation and market analysis of supply chains for torrefied wood pellets from British Columbia: Impacts of plant configuration and distance to market," Renewable and Sustainable Energy Reviews, Elsevier, vol. 127(C).
    4. Ghiasi, Bahman & Kumar, Linoj & Furubayashi, Takaaki & Lim, C. Jim & Bi, Xiaotao & Kim, Chang Soo & Sokhansanj, Shahab, 2014. "Densified biocoal from woodchips: Is it better to do torrefaction before or after densification?," Applied Energy, Elsevier, vol. 134(C), pages 133-142.
    5. Seraj, Somaye & Azargohar, Ramin & Dalai, Ajay K., 2025. "Dry torrefaction and hydrothermal carbonization of biomass to fuel pellets," Renewable and Sustainable Energy Reviews, Elsevier, vol. 210(C).
    6. Yek, Peter Nai Yuh & Cheng, Yoke Wang & Liew, Rock Keey & Wan Mahari, Wan Adibah & Ong, Hwai Chyuan & Chen, Wei-Hsin & Peng, Wanxi & Park, Young-Kwon & Sonne, Christian & Kong, Sieng Huat & Tabatabaei, 2021. "Progress in the torrefaction technology for upgrading oil palm wastes to energy-dense biochar: A review," Renewable and Sustainable Energy Reviews, Elsevier, vol. 151(C).
    7. Batidzirai, B. & Mignot, A.P.R. & Schakel, W.B. & Junginger, H.M. & Faaij, A.P.C., 2013. "Biomass torrefaction technology: Techno-economic status and future prospects," Energy, Elsevier, vol. 62(C), pages 196-214.
    8. Shui, Tao & Khatri, Vinay & Chae, Michael & Sokhansanj, Shahabaddine & Choi, Phillip & Bressler, David C., 2020. "Development of a torrefied wood pellet binder from the cross-linking between specified risk materials-derived peptides and epoxidized poly (vinyl alcohol)," Renewable Energy, Elsevier, vol. 162(C), pages 71-80.
    9. Riva, Lorenzo & Nielsen, Henrik Kofoed & Skreiberg, Øyvind & Wang, Liang & Bartocci, Pietro & Barbanera, Marco & Bidini, Gianni & Fantozzi, Francesco, 2019. "Analysis of optimal temperature, pressure and binder quantity for the production of biocarbon pellet to be used as a substitute for coke," Applied Energy, Elsevier, vol. 256(C).
    10. Nabila, Rakhmawati & Hidayat, Wahyu & Haryanto, Agus & Hasanudin, Udin & Iryani, Dewi Agustina & Lee, Sihyun & Kim, Sangdo & Kim, Soohyun & Chun, Donghyuk & Choi, Hokyung & Im, Hyuk & Lim, Jeonghwan &, 2023. "Oil palm biomass in Indonesia: Thermochemical upgrading and its utilization," Renewable and Sustainable Energy Reviews, Elsevier, vol. 176(C).
    11. Rudolfsson, Magnus & Stelte, Wolfgang & Lestander, Torbjörn A., 2015. "Process optimization of combined biomass torrefaction and pelletization for fuel pellet production – A parametric study," Applied Energy, Elsevier, vol. 140(C), pages 378-384.
    12. Rudolfsson, Magnus & Borén, Eleonora & Pommer, Linda & Nordin, Anders & Lestander, Torbjörn A., 2017. "Combined effects of torrefaction and pelletization parameters on the quality of pellets produced from torrefied biomass," Applied Energy, Elsevier, vol. 191(C), pages 414-424.
    13. Andrzej Kuranc & Monika Stoma & Leszek Rydzak & Monika Pilipiuk, 2020. "Durability Assessment of Wooden Pellets in Relation with Vibrations Occurring in a Logistic Process of the Final Product," Energies, MDPI, vol. 13(22), pages 1-15, November.
    14. González, William A. & López, Diana & Pérez, Juan F., 2020. "Biofuel quality analysis of fallen leaf pellets: Effect of moisture and glycerol contents as binders," Renewable Energy, Elsevier, vol. 147(P1), pages 1139-1150.
    15. Ma, Jiao & Feng, Shuo & Shen, Xiaoqian & Zhang, Zhikun & Wang, Zhuozhi & Kong, Wenwen & Yuan, Peng & Shen, Boxiong & Mu, Lan, 2021. "Integration of the pelletization and combustion of biodried products derived from municipal organic wastes: The influences of compression temperature and pressure," Energy, Elsevier, vol. 219(C).
    16. Sui, Haiqing & Chen, Jianfeng & Cheng, Wei & Zhu, Youjian & Zhang, Wennan & Hu, Junhao & Jiang, Hao & Shao, Jing'ai & Chen, Hanping, 2024. "Effect of oxidative torrefaction on fuel and pelletizing properties of agricultural biomass in comparison with non-oxidative torrefaction," Renewable Energy, Elsevier, vol. 226(C).
    17. Hamid Gilvari & Wiebren De Jong & Dingena L. Schott, 2020. "The Effect of Biomass Pellet Length, Test Conditions and Torrefaction on Mechanical Durability Characteristics According to ISO Standard 17831-1," Energies, MDPI, vol. 13(11), pages 1-16, June.
    18. Agar, David A. & Rudolfsson, Magnus & Lavergne, Simon & Melkior, Thierry & Da Silva Perez, Denilson & Dupont, Capucine & Campargue, Matthieu & Kalén, Gunnar & Larsson, Sylvia H., 2021. "Pelleting torrefied biomass at pilot-scale – Quality and implications for co-firing," Renewable Energy, Elsevier, vol. 178(C), pages 766-774.
    19. Christoforou, Elias A. & Fokaides, Paris A., 2016. "Life cycle assessment (LCA) of olive husk torrefaction," Renewable Energy, Elsevier, vol. 90(C), pages 257-266.
    20. Riaz, Sajid & Oluwoye, Ibukun & Al-Abdeli, Yasir M., 2022. "Oxidative torrefaction of densified woody biomass: Performance, combustion kinetics and thermodynamics," Renewable Energy, Elsevier, vol. 199(C), pages 908-918.

    More about this item

    Keywords

    ;
    ;
    ;
    ;
    ;

    Statistics

    Access and download statistics

    Corrections

    All material on this site has been provided by the respective publishers and authors. You can help correct errors and omissions. When requesting a correction, please mention this item's handle: RePEc:gam:jeners:v:18:y:2025:i:13:p:3464-:d:1692258. See general information about how to correct material in RePEc.

    If you have authored this item and are not yet registered with RePEc, we encourage you to do it here. This allows to link your profile to this item. It also allows you to accept potential citations to this item that we are uncertain about.

    If CitEc recognized a bibliographic reference but did not link an item in RePEc to it, you can help with this form .

    If you know of missing items citing this one, you can help us creating those links by adding the relevant references in the same way as above, for each refering item. If you are a registered author of this item, you may also want to check the "citations" tab in your RePEc Author Service profile, as there may be some citations waiting for confirmation.

    For technical questions regarding this item, or to correct its authors, title, abstract, bibliographic or download information, contact: MDPI Indexing Manager (email available below). General contact details of provider: https://www.mdpi.com .

    Please note that corrections may take a couple of weeks to filter through the various RePEc services.

    IDEAS is a RePEc service. RePEc uses bibliographic data supplied by the respective publishers.