Torrefied biomass (Biotorr) potential for agricultural applications. A review

Crop residue management has gained attention for its potential to increase soil organic matter and improve soil health in agricultural systems. For these purposes, pyrolysis of crop residues, to produce biochar, and its impacts on soils have been extensively studied, but torrefied biomass (biotorr), produced by torrefaction between 200 and 300 °C represents a promising alternative. Torrefaction offers advantages such as higher mass yields and lower production costs, which could make it an accessible and cost-effective soil conditioner. This review synthesises current knowledge on the effects of torrefaction on the properties of biotorr and assesses its potential as a soil conditioner. The results showed that torrefaction affects the composition of biotorr differently depending on the feedstock and the torrefaction parameters. While the yield of biotorr decreased with increasing torrefaction temperature, it was still higher than that of biochar. Compared to the feedstock, the carbon content and stability of biotorr improved significantly. Our analysis also indicated higher levels of P and K in biotorr, although further research is needed to determine their bioavailability. Given these results, biotorr shows a strong potential as a soil conditioner to improve soil health and support sustainable agriculture. However, it is now necessary to further investigate the potential of biotorr for agricultural application through field experiments, especially to assess how biotorr affects soil nutrient dynamics and carbon sequestration.