Study On Pretreatment Of Corn Stover And The Effect Of Hydrogen Preduction By Fermentation

Energy crisis and environmental pollution make it necessary to find an alternative energy source that is environmentally friendly and renewable. Hydrogen is generally considered as a clean and renewable energy. There are many hydrogen production methods, but hydrogen production from biomass by anaerobic fermentation attracts much attentions because of its advantage. Hydrogen production from biomass not only can convert cheap and abundant biomass into useful energy, but also solve the environment pollution. The hydrolysis degree of biomass directly determines the hydrogen yield in the process of hydrogen production from biomass. Therefore, the pretreatment of biomass for biological hydrogen production is critical. In the study, corn stover was adopted as substrate to investigate the optimal conditions of different pretreatments and to determine the effects of different pretreatments on hydrogen production.The experiment mainly studied the following pretreatments:steam explosion pre-treatment, dilute acid hydrolysis pretreatment, dilute alkaline hydrolysis pretreatment, steam explosion joint dilute acid hydrolysis pretreatment and steam explosion joint dilute alkaline hydrolysis pretreatment. H2SO4 and HCL were selected as acids of dilute acid hydrolysis pretreatment, NaOH was selected as alkaline of dilute alkaline hydrolysis pretreatment. First, the influential factors of each pretreatment of the corn stover on the hydrolysis ratio was studied and span of the influential factors were attained by single factor experiments in the hydrolysis rate of corn stover. Second, found out optimum conditions of each pretreatment through experiments. Finally, hydrogen production capacities of each pretreatment method in optimum conditions were compared.Through comparing hydrogen production capacity of different pretreatment methods, we can conclude that the advantage of joint pretreatment was obvious. Especially steam explosion joint H2SO4 hydrolysis pretreatment was proved to be the best pretreatment. And the optimum conditions of this pretreatment were as follows: the steam explosion pressure was 1.5Mpa, the steam explosion temperature was 125℃, the steam explosion time was 5min, the Concentration of H2 SO4 was 0.8%, the hydrolytic temperature was 90℃, the hydrolytic time was 60min. Under these conditions, the hydrolysis rate of corn stalk reached 45.02%, per-gram corn stalks of hydrogen yield reached 142ml,and the maximum hydrogen concentration was 57.4%.