Using mixed anaerobic communities to convert low value biomass into hydrogen

目前对微生物制氢的研究集中在使用纯培养物和混合培养物。 纯培养物的研究使用无菌基质以防止污染。 基质灭菌是使用纯培养物的工艺的主要缺点。 能够利用非无菌原料的微生物培养物可能更灵活且更具成本效益。 玉米秸秆和小麦秸秆等低价值农业残留物可能是非无菌原料的来源。含有产酸菌、产乙酸菌和产甲烷菌的混合培养物可以消耗来源于低价值农业残留物的糖。 然而，与持续产氢相关的主要问题是混合厌氧群落中存在耗氢生物。 拟议的研究将集中在使用长链脂肪酸（LCFA）来抑制氢消耗群体。 该研究计划为研究和开发利用低价值农业剩余物的厌氧制氢工艺提供了一个纲要。 短期目标将确定影响氢生产的环境和工艺参数。 将进行分批研究，以检查几种长链脂肪酸（LCFA）对戊糖和己糖发酵的影响。 在分批和连续流研究中，通过灭活非芽孢形成的耗氢微生物并选择更有利的产氢细菌，将采用添加LCFA来增加产氢量。 长期目标的主要重点将集中在开发可持续的连续制氢系统。

Current research on microbial hydrogen production is focused on using pure and mixed cultures. Studies with pure cultures have utilized sterile substrates to prevent contamination. Substrate sterilization is a major disadvantage for processes using pure cultures. Microbial cultures which are able to utilize non-sterile feedstocks could be more flexible and cost effective. Low value agriculture residues such as corn stover and wheat stalks are possible sources of non-sterile feedstocks. Mixed cultures containing acidogens, acetogens and methanogens can consume sugars derived from low value agriculture residues. However, a major concern related to sustained hydrogen production is the presence of hydrogen consuming organisms in mixed anaerobic communities. The proposed research will focus on using long chain fatty acids (LCFAs) to inhibit the hydrogen consuming population. The research plan provides an outline for investigating and developing an anaerobic process for producing hydrogen using low value agriculture agriculture residues. The short-term objectives will identify environmental and process parameters affecting hydrogen production. Batch studies will be conducted to examine the effect of several long chain fatty acids (LCFAs) on the fermentation of pentose and hexose sugars. Adding LCFAs will be employed to increase hydrogen production by inactivating non-spore forming hydrogen consuming organisms and selecting the more favorable hydrogen producing bacteria in both batch and continuous flow studies. The major thrust of the long-term objectives will focus on developing a sustainable continuous system to generate hydrogen.