Influence of initial pH on hydrogen production from lipid-extracted microalgal biomass residues
初始pH值对提油后藻渣发酵制氢的影响

It is significant for development of microalgal biodiesel industry to utilize lipid-extracted microalgal biomass residues. Hydrogen production from lipid-extracted microalgal biomass residues was performed via batch tests by using heat treated anaerobic digested sludge, and the effect of initial pH 5~9 on the biohydrogen production was firstly investigated. The results showed that increasing the initial pH led to decreases in hydrogen yield and cumulative hydrogen production. The hydrogen production rate increased with initial pH from 5 to 6.5, and then decreased as the pH further increased to 9. The lowest initial pH 5 offered the highest hydrogen yield of 50 mL H2/g VS (volatile solid), a lower hydrogen production rate of 2.69 mL H2/h, and a longer lag-phase of 20 h, whereas the highest hydrogen production rate of 3.79 mL H2/h and a lower lag-phase time of 1.7 h occurred at optimal initial pH 6.5.