Effect of Torrefaction on Pellets Made From Vegetal Biomass Generated by Fruit Shrubs

This study investigates the effects of torrefaction on the properties of pellets produced from vegetable biomass residues of fruit shrubs. The research focuses on two pellet formulations: (1) a blend of sea buckthorn (Hippophae rhamnoides L.) and blackberry (Rubus fruticosus) residues and (2) a mixture of sea buckthorn residues with wheat straw. The torrefaction process was conducted in an inert argon atmosphere at temperatures between 200 °C and 300 °C for durations ranging from 10 to 30 min. The study assessed the impact of these parameters on the net calorific value and ash content of the pellets. Results indicate that torrefaction significantly enhances the calorific value of the biomass, with optimal conditions identified at 250-280 °C and exposure times of 15-25 min. However, excessive temperature and duration lead to mass losses and increased ash content. These findings provide insights into optimizing torrefaction parameters for improving the quality of densified solid biofuels derived from agricultural residues.