| Fermentative biohydrogen production technology can take advantage of thelow utilization of organic waste water and waste material, both preparation ofhydrogen, but also to improve the environment, and widely recognized in practicalapplications. However, the existence of small organic molecules of acid and alcoholin the fermentative end product can not be fully utilized, which reduced theefficiency of hydrogen production. Microbial electrolysis cell （MEC） is at theforefront of biological hydrogen production technology, which combined with theadvantages of biological metabolism and the electrochemical reaction that thefunctional microbes grow with small molecular organic acids and give out higherhydrogen energy than input in to a small auxiliary voltage. It’s happened to acidifyon the conditions of high concentration of carbohydrates to degradate the hydrogenproduction performance.It’s a problem for biological hydrogen productiontechnology to promote the hydrogen production with carbohydrate. This papermainly discusses the influence of environmental factors on the ethanol-typefermentation hydrogen production and aggregation. If two or more biologicalhydrogen production process could be integrated into a simple set of biologicalhydrogen production system, such as ethanol-H2-coproducing fermentation coupledwith MEC, it can be the biggest improvement of substrate utilization and hydrogenproduction capacity, which have an important practical and theoretical significance.When Ca2+concentration was0.5g/L, agg%of Ethanoligenense harbinenseYUAN-3was more than90%. The H2evolution decreased with adding the Ca2+concentration. When Ca2+concentration was0.1g/L, the H2evolution for strainX-29was1400ml-H2/L-medium. The agg%of Strain X-29was about10%. Ca2+dosing has little effect on the agg%of strain X-29. It achieved good results for theaggregation and hydrogen production of strain YUAN-3on the0.1g/L Fe2+concentration and0.8g/L L-cysteine. It has found the different protein relevant toaggragration. The structure of the protein is similar as Putative GntR ofSinorhizobium meliloti1021.The study on substrate utilization and H2evolution with different disaccharidesas fermentation substrate by strains YUAN-3was carried out. There is highersubstrate utilization and H2evolution compared with other disaccharides as substrate.When sucrose concentration was35g/L, the H2evolution was1936ml-H2/L-medium. The substrate utilization was100%on the sucrose concentrationwas20g/L. When lactose concentration was24g/L, the H2evolution was1387ml-H2/L-medium. The substrate utilization was in exceed of90%on the lactose concentration was less than10g/L. However, maltose as a substrate, substrateutilization and H2evolution are relatively low.H2production from sucrose by combining ethanol-H2-coproducingfermentation with single-chamber MEC. The hydrogen yield was2.82mol-H2/mol-medium when strain YUAN-3compounding with Shewanella sp. NH41on one-step hydrogen production. The hydrogen yield was2.95mol-H2/mol-mediumwhen strain YUAN-3compounding with Shewanella sp. NH41and Geobactersulfurreducens PCA. MEC segment of the hydrogen production rate was55.37mmol-H2/g-COD. Hydrogen conversion rate was increased by83%, and thesubstrate conversion rate was increased by56%compared withethanol-H2-coproducing fermentation. |
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