Potential improvement of biogas production from fallen teak leaves with co-digestion of microalgae.

Biogas production from anaerobic co-digestion of fallen teak leaves ( Tectona grandis ) and microalgae ( Chlorella vulgaris ) were investigated. In this study, teak leaves and algae mixtures with or without pretreatment were used as the substrates and digested in 1-L of anaerobic fermenter, then optimal conditions were performed in 6-L fermenter. Pretreatment was performed using sodium hydroxide (NaOH) solution (w/v) at different conditions (0, 2, 3 and 4%), with different total solid (TS) ratios (10, 15 and 20%). The digesters were placed in an incubator at 34-36 °C for 45 days. The results showed that the co-digestion of pretreated (10% TS with 2% NaOH) of teak leaves and algae was significantly higher in terms of biodegradability of TS, VS, COD along with biogas yield, methane potential and highest yield was achieved 71.90% than those obtained by mono-digestion. Thus, results demonstrated that anaerobic fermentation of teak leaves and microalgae in digester system could get as high methane yield.