Brewer's Grains And Corn Straw By Anaerobic Fermentation Of Biological Hydrogen Production

Biological hydrogen was produced with anaerobic batch culture from simulated wastewater containing pretreated beer lees or cornstalk by hydrogen-producing microorganisms obtained from cow dung compost. The effects of pretreatment, substrate concentration, and initial pH on hydrogen production potential were examined.The experimental results indicate that pretreatment is a key factor that strongly affected the hydrogen production potential of substrate. After pretreatment, the hydrogen production potentials of beer lees and cornstalk increased remarkably, with an increase from 5.4 and 2.68ml/gTS to 54.4 and 126.8ml/gTS, respectively. The optimal pretreatment is that substrates were boiled for 30mins in 0.2%HCl solution. The results also demonstrated that optimal ranges of beer lees concentration and initial pH for the composts generating hydrogen gas were 15-25 g/L and 6.0-7.0, respectively. High hydrogen potential of 54.4mL/gTS occurred under this condition. The maximum hydrogen composition of biogas was 45%. Optimal ranges of cornstalk concentration and initial pH for the composts generating hydrogen gas were 15-20 g/L and 6.0-7.0, respectively. High hydrogen potential ofl26.8mL/gTS occurred under the conditions that cornstalk concentration is 15g/L and initial pH 7.0.The maximum hydrogen composition of biogas was55% and no methanogenesis was observed.Experimental results of metabolites analysis led us to the belief that Clostridium sp. predominated in anaerobic composts, suggesting that inocula used to seed the batch experiment can be obtained from almost any natural source. Hydrogen-producing microorganisms could be enriched from natural microbial sources by heat shock or forcing aeration. Compared with traditional heat shock, forcing aeration is a more effective method and is simple on the technical ground.