Granulation and pyrolysis of agricultural residues for an enhanced circular economy
Results in Engineering 2025
Maryna Zhylina, Andrejs Šiškins, Denis Miroshnichenko, Vita sterna, Jurijs Ozoliņš, Linda Ansone-Bertina, Maris Klavins, Gaurav Goel, Saurav Goel

This study highlights a sustainable approach to agricultural waste management by transforming residues into value-added products through granulation and pyrolysis. Agricultural biomass, a prevalent waste stream, holds great potential as a key ingredient for enhancing soil health. However, the common practice of incineration diminishes this opportunity by wasting valuable resources. This investigation sought to demonstrate that lowtemperature slow pyrolysis of biomass can be used to create value-added products such as animal feed, biochar, and heating briquettes. The study involved a comparative analysis of wheat straw, barley straw, and oat husk for biochar production, examining key properties like moisture content, ash content, and fiber composition. The optimal granulation process for combining these materials with peat was established, resulting in robust pellets consisting of 85 % biomass and 15 % peat. Pyrolysis was conducted at 500 ◦C with a heating rate of 5 ◦C per minute. The resulting granules were evaluated for their strength, density, and moisture absorption. The barley straw pellets were found to have the best mechanical strength of 89.40 N, the best moisture absorption capacity of 49.50 % and the highest product yield of 54.1 % after pyrolysis. When used in lettuce cultivation, the combination of peat with barley straw as a binder yielded the most promising results. Introducing circularity in biomass reduces waste, enhances soil health and creates economic opportunities, reinforcing the principles of a circular economy. This approach promotes resource efficiency, minimizes environmental impact and contributes to a more sustainable agricultural sector. 1.


Keywords
Biomass, Peat, Granulation, Pyrolysis, Biochar, Soil quality
DOI
10.1016/j.rineng.2025.104919
Hyperlink
https://www-sciencedirect-com.resursi.rtu.lv/science/article/pii/S2590123025009958

Zhylina, M., Šiškins, A., Miroshnichenko, D., sterna, V., Ozoliņš, J., Ansone-Bertina, L., Klavins, M., Goel, G., Goel, S. Granulation and pyrolysis of agricultural residues for an enhanced circular economy. Results in Engineering, 2025, Vol. 26, pp.104919-104931. Available from: doi:10.1016/j.rineng.2025.104919

Publication language
English (en)
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