不同气相条件对单株产氢菌降解煤制氢的影响

Effects of Different Gas Phase Conditions from Coal Bed Hydrogen-production

为探究不同气相条件对产氢效应的影响,从煤中成功分离出一株高效产氢菌,采用液体培养基进行富集培养,经16SrDNA序列比对分析发现该菌株与肠杆菌属的Enterobacter cloacae同源性最高。讨论了不同碳源对产气效果的影响,优选出葡萄糖作为该菌最适宜的营养物质。利用葡萄糖作为培养基中的碳源进行富集,以煤为底物进行产氢发酵实验,分别通入氦气、二氧化碳、一氧化碳和空气,测定菌液浓度,讨论不同气氛条件下对产气效果的影响。结果表明:通入氦气菌液浓度明显提高,产氢效果最好,产氢效率达到1.87 mL/h;通入一氧化碳产氢效果最差,通入空气对产氢有明显的抑制作用,通入二氧化碳能促进产氢但效果不如氦气;对反应末端的固体分析后发现不同气相条件下煤的密度变化不大;通入氦气的煤样兰氏体积增大约10%,证明氦气条件下Enterobacter cloacae对煤的利用更彻底。

In order to explore the effect of different gas phase on the production of hydrogen-producing levels,a highly efficient hydrogen-producing strain was isolated from the coal.Enrichment culture was carried out with liquid medium.The comparative analysis of 16SrDNA sequence indicates that this strain has the highest homology with Enterobacter cloacae.And the glucose is the most suitable carbon source.In the experiment of hydrogen production,coal was used as a substrate for degradation of the strain,helium,carbon dioxide,carbon monoxide and sterile air were used as different gas phase conditions in hydrogen production experiments.Turbidity and hydrogen production rate were used to evaluate the effect of four gas phase conditions on hydrogen production.The results show that the helium can significantly increase the concentration of strain to achieve the best hydrogen production effect and the hydrogen production rate is 1.87 mL/h.Carbon dioxide can promote hydrogen production to some extent,but hydrogen production is less effective than helium,and carbon monoxide has the lowest effect on hydrogen production in these gas phases.Sterile air has obvious inhibition effect on hydrogen production.The density of coal has not changed significantly after degraded by the strain.The coal samples after hydrogen production under helium were used for isothermal adsorption experiments,and it was found that the volume of Rankine increases by about 10%,which indicates that Enterobacter cloacae can utilize coal more thoroughly under helium-gas condition.