温度相厌氧消化强化长链脂肪酸转化的效能与机理研究

富脂废物厌氧产能潜力巨大，水解产物长链脂肪酸(LCFAs)的β氧化是代谢瓶颈。一般认为：LCFAs抑制微生物阻碍了β氧化，但前期研究表明：生物可利用性是除抑制外的另一关键因素；提升消化温度可以提高生物可利用性。在传统中温消化前增设超高温或高温预消化的温度相厌氧消化(TPAD)因具有较高代谢效率和稳定性而逐渐受到重视，但LCFAs在TPAD工艺，特别是在预消化条件下的转化效能和机理尚不清楚。本项目首先在调查LCFAs转化路径以明确具体限速步骤的基础上，论证饱和LCFAs生物可利用性对β氧化的重要性；采用提升温度的方法，研究生物可利用性的提高效能和对微生物活性的影响机制，并考察生物可利用性提高后的抑制水平和耐受负荷；最后通过开展连续试验，探明TPAD对LCFAs转化的强化效能，并揭示实际运行的相关机理。本项目的实施有助于深入理解LCFAs的β氧化过程，将为富脂废物高效稳定的能源化利用提供可能。

Lipid-rich waste is of enormous potential in energy yield by anaerobic digestion. The β-oxidation of long chain fatty acids (LCFAs), hydrolysis product from lipid-rich waste, limits the anaerobic process. It is generally accepted that the obstacle of β-oxidation is from the LCFA inhibition on biomass. Nevertheless, the previous study indicates that bioavailability of LCFAs is another key factor besides inhibition, and digestion at elevated temperatures can increase bioavailability. Temperature-phased anaerobic digestion (TPAD), adding hyperthermophilic or thermophilic pre-fermentation prior to the conventional mesophilic digestion, is paid more attention due to higher degradation efficiency and stability. Unfortunately, the efficiency and mechanism of LCFA conversion in TPAD, especially in the pre-fermentation stage, are still unknown. First of all, the significance of saturated LCFA bioavailability to β-oxidation will be demonstrated, on the premise of clarifying specific rate-limiting step by investigating the LCFA conversion process. Secondly, at elevated digestion temperatures, the study on the increased efficiency of bioavailability and the influence mechanism of bioavailability on biomass viability, as well as the inhibition level and tolerant loading, will be conducted. Lastly, a continuous experiment will be carried out to investigate the efficiency of LCFA conversion enhanced by TPAD, and to uncover the relevant operation mechanisms in practice. This study favors further understanding for the anaerobic β-oxidation of LCFAs, and also make the efficient and stable waste-to-energy application of lipid-rich waste possible.