SUGARCANE BAGASSE ALKALINE PRETREATMENT TO IMPROVE BIOMETHANE PRODUCTION

Abstract

The sugar cane bagasse constitutes an abundant lignocellulosic agro-industrial residue in Cuban sugar industry. However, its complex structure partially limits biodegradation, for that reason it is necessary to apply a pretreatment, being the alkaline the most effective for biomasses with a high lignin content. This work objective is to evaluate the effect of alkaline pretreatment in cane bagasse delignification, and its anaerobic biodegradability with respect to without pretreatment bagasse. Two alkalis (NaOH and KOH) with two concentration levels (0.5 and 1% w/v), and two contact times (1 and 3 h), were studied at room temperature. Results were evaluated in terms of % delignification, methane yield and process kinetics according to a first order model. Maximum lignin reduction (36.5%) and methane yield (192 mLCH4/g VS) were obtained with NaOH (0.5% -3h), achieving a 94.6% increase in methane yield respect to without pretreating bagasse. Kinetic study confirmed that kinetic parameters are improved compared to without pretreatment bagasse, with this variant.