Local variability of yield and physical properties of açaí waste and improvement of its energetic attributes by separation of lignocellulosic fibers and seeds

The high degree of variability among suppliers and types of biomasses hinders their application in energy production. Investigation into this drawback is needed for the use of the waste produced from acai depulping, which is widely available throughout the Amazonia. This work aimed to analyze the variability of the yield and physical properties of the acai waste among different Amazonian producers located at Macapa, AP, Brazil. In addition, energetic attributes of different waste components, namely, seeds and lignocellulosic fibers, were compared to determine if they should be separated prior to burning or pyrolysis. The average yield (71.0%-95.0%), dry basis moisture content (66.6%-76.2%), and basic density (0.753 g cm(-3) to 0.812 g cm(-3)) of acai waste varied remarkably among the suppliers. Fibers and seeds depicted similar higher heating values (19.91MJ kg(-1) and 19.32MJ kg(-1)) and fixed carbon (21.39% and 21.50%) and volatile matter (77.32% and 76.65%), while the ash content was slightly lower for seeds (1.29%-2.08%) in comparison to fibers (1.85%-2.63%). Thermogravimetric analysis revealed different initial degradation temperatures and mass loss rates for the seeds and fibers. It was concluded that the yield and physical properties of acai waste varied remarkably among providers. A drying process should be carried out before acai waste burning due to its high moisture content. The high basic density is an advantageous feature of acai waste in the context of bioenergy. Separation of the components is recommended prior to pyrolysis to avoid heterogeneous charcoal. Published by AIP Publishing.