PULP PRODUCTION FROM BANANA PLANT STEM, Musa sp

摘要

The banana stem, grain stalk that supports the banana fruits, is normally discarded after the fruit harvesting, either in the "packing houses" or in the delivering centers, where it is considered a residue due to the great volume generated. For this reason and for being made of fibrous material, stem was evaluated for pulp production. The stem in natura presents 93 % of humidity and parenchymatics cells in abundance; in terms of chemical composition the stem presents 7,4% of lignin, 47 % of total extractives and 45,6% of holocelullose. In this research, the pertormance of the stem as raw material for pulp production was evaluated, using the CaO as an alkali source. Washing and pre-hydrolysis were considered as pre-process steps in order to reduce the amount of extractives on the banana stem bagasse; the washing process were conducted at 4% of consistency and the pre-hydrolysis at 100 ℃ for 100 minutes; the original bagasse and the ones obtained after the pre-process steps were submitted to the CaO pulping with 8, 10, 12 and 14 % of CaO, at 120 ℃ temperature during 120 minutes in rotating digester. For comparison reasons, a soda cooking was carried out, under the same conditions using 12% of NaOH as alkaline charge. The results had shown that the application of washing and pre-hydrolysis caused a reduction of about 50% in the initial mass of bagasse. Considering the pulping conditions and also the chemical composition of the banana stem bagasse the pre-process steps evaluated did not present a significant effect on the cooking process itself. For the banana stem pulping a CaO process can be considered a technical alternative for pulp production, with delignication rates simular to the NaOH process but with a higher yield.