Vol. 337 No. 10 (2026)
DOI https://doi.org/10.18799/24131830/2026/10/5350
Impact of particle size distribution of biochar from pine nut shells and starch binder proportion on the properties of composite granules
Relevance. The necessity for efficient disposal of cedar nut shells and research on their pyrolytic processing to obtain useful products. A promising method for processing cedar nut shells is the production of biochar for the subsequent formation of composite pellets to improve the product transport, energy, and operational characteristics. A special factor is the possibility of cost-effective transportation of the resulting products in the form of pelletized fuel, which will improve not only transportation but also operational characteristics. Aim. To establish the effect of the granulometric composition of biochar derived from cedar nut shells and starch binder mass fraction on the mechanical and thermotechnical characteristics of composite granules for their subsequent application in small-scale power engineering. Methods. Proximate and ultimate analysis of biomass are determined according to certified methods, elemental composition – on the elemental analyzer UNICUBE. Textural characteristics of the samples were determined using a 3P sync 210A specific surface area and porosity adsorption analyzer. The material balance of pyrolysis was established through physical experiments. The mechanical properties of the granules were determined in accordance with SS 21289-75. Results and conclusions. The study demonstrated that pyrolysis of pine nut shells yields high-quality, low-ash biochar with a calorific value of up to 32.42 MJ/kg. The maximum mechanical strength of the pellets (SM>99% and DUr>92%) was achieved using a biochar fraction of 0.2–0.5 mm and a 5–7% starch binder. Starch proved to be an effective binding agent, with a content of 3–5% sufficient to ensure transport durability. All produced pellets exhibited high thermotechnical properties ( >31.3 MJ/kg, Ad<1.8%) and complied with the standards for premium smokeless fuel, confirming the promise of the developed technology.
For citation: I.D. Dimitryuk, M.A. Gaydabrus, K.T. Ibraeva. Impact of particle size distribution of biochar from pine nut shells and starch binder proportion on the properties of composite granules. Bulletin of the Tomsk Polytechnic University. Geo Assets Engineering, 2026, vol. 337, no. 10, pp. 103–116. http://doi.org/10.18799/24131830/2026/10/5350
Keywords:
biochar, granulation, binder, particle size distribution, mechanical strength, pyrolysis, smokeless fuel, energy
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