Department of Civil Engineering, University of Idaho, P.O. Box 441022, Moscow, ID 83844-1022, USA.
Bioresour Technol. 2012 Mar;107:205-12. doi: 10.1016/j.biortech.2011.12.077. Epub 2011 Dec 29.
Over 9 million dairy cows generate an estimated 226 billion kg of wet manure annually in the US. The purpose of this study was to demonstrate the viability of a novel two-stage anaerobic digestion (AD) process for producing methane-rich biogas on pre-fermented dairy manure. In summary, it was observed that AD of thickened pre-fermented manure can generate comparable biogas quantities to AD using raw manure, with enhanced methane content. Despite receiving a lower quality (i.e., partially biodegraded) substrate, biogas stoichiometry and overall process stability in the two-stage system was also comparable to AD receiving raw manure. Finally, the two-stage AD was more enriched with the acetoclastic methanogen Methanosarcinaceae (Msc; compared to AD of raw manure) and biogas production appeared closely linked with the Msc fraction. In fact, the enhanced enrichment of Msc likely contributed to the successful and stable operations.
在美国，每年有超过 900 万头奶牛产生约 2260 亿公斤湿粪。本研究的目的是展示一种新型两段式厌氧消化（AD）工艺的可行性，该工艺可在预发酵奶牛粪便上生产富含甲烷的沼气。总之，研究发现，浓缩预发酵粪便的 AD 可以产生与使用生粪进行 AD 相当的沼气量，同时甲烷含量更高。尽管接收的是质量较低（即部分降解）的底物，但两段式系统的沼气化学计量和整体过程稳定性与接收生粪的 AD 相当。最后，两段式 AD 中更富含产乙酸甲烷菌 Methanosarcinaceae（Msc；与 AD 接收生粪相比），沼气产生似乎与 Msc 部分密切相关。事实上，Msc 的增强富集可能有助于成功和稳定的运行。
