Potentials for utilization of post-fiber extraction waste from tropical fruit production in Brazil - the example of banana pseudo-stem.

Abstract

This work presents an estimation of potential fiber recovery as well as non-fiber biomass generated from banana pseudo-stem, using Brazil as example. Characteristics and potential uses of non-fiber biomass are presented and explored, based on a literature review. The yearly generation of banana pseudo-stems in Brazil reaches 14 million tons. The potential fiber extraction from this waste was estimated to 1.11 million tons per year. Banana pseudo-stems have a high content of glucose and cellulose in the range of 52.2- 74% and 42.2-63.9% of dry solids (DS) respectively, a nitrogen, phosphorus and potassium content around 0.3-2.8, 0.2-0.5 and 4.0-4.6% of DS respectively, according to previous findings. The carbon/nitrogen ratio was reported in levels of 21-66. Previous studies have shown potentials of energy recovery from banana stem waste in the order of 64-196 dm 3 CH4/kg DS through anaerobic digestion and 1.87-2.65 kg ethanol/kg dry solid (1 st generation) or 0.70-4.71 kg ethanol/kg dry solid (2 nd generation). Potentials for energy recovery from ethanol stillage are also discussed, but banana stem generated stillage are poorly described in the literature and more studies are needed to improve estimations of potentials for energy recovery also from these fractions. The gross energy recovery from banana pseudo-stems generated yearly in Brazil can vary from 4625-10300 TJ with a recovery of N-tot of 9-18 thousand tons, depending on chosen treatment combinations. Thus, fiber extraction together with combinations of technologies for energy and nutrient recovery could be of large interest in countries with high generation of banana waste.