Effect of bacterial pretreatment on solid sago waste for enhanced biomethane generation

Abstract

The sago processing industry was considered to be one of the major sources of revenue in some countries. During processing, an enormous amount of carbohydrate rich waste is generated, thus making it a feasible substrate for bioenergy production. Despite its nutrient content, the complex structure of this substrate restricts the hydrolysis phase during anaerobic digestion. In this study, an investigation was made to augment the hydrolysis of sago waste by enzyme-secreting bacterial pretreatment. At 42 h, the solubilization enhanced to 10.4 % in SBN (a medium consisting of sago and nutrient inoculated with bacteria) as compared to the SB (a medium containing sago inoculated with bacteria) (4.2 %). After pretreatment, the biomethane potential assay shows that the methane generation was boosted to 28.1 mL/gCOD in the SBN sample compared to SB (11.9 mL/gCOD) and raw sago sample (3.2 mL/gCOD). The higher biomass solubilization enables easier accessibility of substrate for methane production.