Potencial energético do resíduo do despolpamento do açaí sob diferentes condições de estocagem.

Abstract

The investigation of biomass quality in fresh condition and after storage in the environment is necessary to subsidize its use for energy generation. In the Amazon, the residue produced from the pulping of açaí stands out for its wide availability. The objective of the work was to evaluate if the different methods and places of conditioning modify the physical, chemical and energetic properties of the açaí residue and its potential for energy purposes. The residues were collected in Macapá, state of Amapá, under six different conditions: a fresh sample, obtained after pulping, and five stored in different environmental conditions. After pulping, the açaí residue had a moisture content of 103.8%, but storage resulted in natural drying, reducing this property to up to 12.3%. Compared to fresh waste (0.719 g cm-3), the basic density of biomass dispersed in wasteland significantly decreased (0.279 g cm-3), which increases transport costs and reduces combustion and pyrolysis yields. . The volatile content increased from 65.29% to up to 75.62%, while fixed carbon decreased from 34.70% to up to 23.09% and ash from 1.81% to up to 1.24%, when the waste were stored. Such modifications suggest the decomposition of part of the chemical components of the açaí residue that become volatile or leachable. As a consequence, the storage reduced the calorific value and energy density of the residues. It was concluded that the storage of the açaí residue in any condition, with the exception of the decrease in humidity, harmed its energy potential.