生物强化促进高含氮有机物厌氧消化产甲烷技术及机理研究

The traditional physical and chemical methods used today to counteract the ammonia inhibition problem during anaerobic digestion are time-consuming and cost-expensive, thus can not be a long-term solution. Based on the primary research, this project will be focused to tackle the ammonia inhibition problem by bioaugmentation. First of all, a comprehensive selection will be done within aceticlasitic methanogens, acetate-oxidizing bacteria and hydrogenotrophic methanogens in order to improve the methane yield and alleviate the ammonia inhibition. Secondly, the long-term efficiency of bioaugmentation on improving methane production and organic material degradation will be tested, and the influence of bioaugmentation on the pathway of methane production will be investigated. High-throughput sequencing and metagenomics will be used as the main tools to study the species composition and functional roles of the microbial community, the quantitative and distribution of different methanogens will be characterized further by FISH and q-PCR. The biochemical reactions and dynamics of ammonia inhibition and bioaugmentation will also be explored, and the mathematic model for mass transfer, biochemical reaction will be established. The aim of this proposal is for those anaerobic digesters operated in ammonia induced “inhibited steady-state” to reach a whole new “efficient steady-state”. The study will provide theoretical and technical solutions for the application of the proposed process.

厌氧消化产甲烷过程受高氨氮抑制的问题亟待解决，目前的解决方法大多效力有限且费钱耗力，不适宜作为长期的解决方法。本申请在前期可行性研究基础上，研究开发利用生物强化技术促进高含氮有机物厌氧消化产甲烷的技术及机理。本研究将首先在明确氨氮对产甲烷抑制机理的基础上，筛选在高氨氮条件下能够有效促进厌氧消化产甲烷的不同类型的强化微生物；重点考察生物强化高含氮厌氧产甲烷反应器的工艺运行特性，揭示强化微生物对有机物代谢途径的影响；进一步结合宏基因组测序等分子生物学手段，阐明强化微生物促进高氨氮有机物厌氧消化产甲烷的微生物生态学机理；最后根据不同工艺运行条件下获得的实验数据构建生物强化高氨氮厌氧体系高效产甲烷的生化反应动力学模型，反馈优化实际操作。通过本研究，实现受高氨氮抑制而处于“抑制的稳定状态”的产甲烷反应器向“高效的稳定状态”转变的目标，为实际应用提供理论依据及技术支撑。

厌氧消化工艺是资源化处理有机废水/有机废弃物的重要技术。高氨氮是影响厌氧消化性能的抑制因素之一。相比于解决高氨氮抑制的物理和化学方法，生物强化可以经济高效地促进高含氮有机物厌氧消化产甲烷过程。本项目在明确氨氮对产甲烷抑制浓度以及抑制机理的基础上，筛选在高氨氮条件下能够有效促进厌氧消化产甲烷的不同类型的强化微生物；重点考察含关键生物强化菌株的高含氮厌氧产甲烷反应器的工艺运行特性，揭示强化微生物对有机物代谢途径的影响。在此基础上，进一步针对实际高含氮有机物（猪粪、牛粪）厌氧消化体系进行生物强化，结合分子生物学手段阐明强化微生物促进高氨氮有机物厌氧消化产甲烷的微生物生态学机理。同时基于厌氧消化1号模型（ADM1）构建生物强化高氨氮厌氧体系高效产甲烷的生化反应动力学模型。通过生物强化实现受高氨氮抑制而处于“抑制的稳定状态”的产甲烷反应器向“高效的稳定状态”转变的目标。