PHYSICAL CHARACTERIZATION OF BRAZILIAN AGRICULTURAL AND FORESTRY RESIDUES AIMING THE PRODUCTION OF ENERGY PELLETS

摘要

Brazil is one of the world largest producers in sugar cane, coffee, and rice. These crops result in highamounts of agricultural residues such as rice and coffee husks and sugar cane bagasse. The residues are bulky (lowdensity) in nature. The low density of the residues makes them difficult in transportation and storage. Thedensification of residues through pelleting processes enhances the storage and transport efficiencies. The presentwork investigates the implementation of pellet production for Brazilian conditions, taking into account thedistribution of crops and residues around the country. This work also discusses the current utilization, socioeconomicand environmental implications involved in pelleting the agricultural residues. The physical properties ofthe residues influence the quantity and quality of materials employed for obtaining suitable pellets. The densificationbehaviour of single residue samples of coffee, rice husks and sugar cane bagasse have been investigated consideringvisually noticeable mechanical parameters. Different moisture contents and particle sizes due to grinding of residueswere employed. The results demonstrated that all the biomass residues could be compressed in the pelleting device,however presenting different mechanical properties. These results are the first appraisal of a series of foreseenresearch activities. Since technical and socio-economic data are scarce to allow the analysis of the overall processviability from residues to pellets in Brazil, the challenge is to assess and evaluate the implementation of energy pellet production for the future.