2.2. Experimental design
Fig. 1 describes the production of high grade bioenergy by converting
biomass wastes to biogas and biodiesel, the details of the
experiments are as follows. The experiments for evaluating the
biogas production ratios were performed in 2.5 L glass bottles with
working volume 2 L. Glass bottles were used as anaerobic digestion
vessel in this study. The bottles were sealed with rubber stoppers
with drilled holes, and a slender glass tube with a silicone tube
was inserted to export gas for biogas volume and composition
measurement. Biogas production was recorded by quantifying
water displacement everyday. Each experiment contained about
30% inoculums. However, ratios between corncob and PM (based
on VS) were 5:2, 2:1, 3:2, 1:1 and 2:3, with constant 150 g of PM
with inoculums, filled water into glass bottles until 2000 g.
Meanwhile, there was a control with 150 g of PM with inoculums
in glass bottle. Then put all the experiments in water bath and controlled
the temperature at 35 ± 2C for anaerobic fermentation. The