Biomethane potential from sugarcane straw in Veracruz, Mexico: Combined liquid hot water pretreatment and enzymatic or biological hydrolysis

Few studies have analysed the utilization of raw sugarcane straw (SCS) for biogas generation. It is important to highlight that these studies only report the biomethane potential (BMP) of the SCS, several form of pretreatment obtained low yields of biomethane compared to the highest BMP obtained here. This study presents data on improving Total BMP from SCS (378.80±0.11 ml CH4/g VSR), in order to lower the severity of the LHW (Liquid Hot Water) pretreatment and to enhance the efficiency of the enzymatic or biological hydrolysis pretreatment, two-step was employed, as follows: (LHW, 120° C, 1.5 bars, 31.25 gr SCS dry basis/L of reaction) with enzymatic hydrolysis (commercial cellulose ENMEX® at 20%) or biological hydrolysis (isolated lignocellulolytic bacteria 3.02 * 108 UFC/ml). This study found a higher BMP in the case of the biological hydrolysis treatment in comparison with the enzymatic one, 360.58 and 344.97 ml CH4/g VSR respectively. Furthermore, the alteration of the physicochemical composition and physical structure of SCS fibre was higher in the option combining LHW pretreatment and biological hydrolysis. This study can be useful as a future reference in Mexico for a scalable system, in order to assess its feasibility for biomethane generation as a sustainable source.

Keywords: Sugarcane Straw, liquid hot water, biomethane potential, enzymatic hydrolysis, biological hydrolysis.