Acetoclastic and Hydrolytic Activity in Anaerobic Digestion--Keys to Process Stability and Process Control

0332118弗格森消化涉及一个复杂的微生物群落，底物的顺序转化和种群之间的相互依赖。颗粒有机物的分解和水解通常被认为限制了消化过程中固体的整体降解，而从醋酸盐中生产甲烷长期以来一直被认为与工艺稳定性有关。这些过程是直接相关的，因为水解和发酵会产生醋酸盐，而利用醋酸盐的(乙酰裂解)产甲烷菌会消耗它。生产速度可能超过消耗速度，导致醋酸盐(和其他短链脂肪酸)积累，pH下降，抑制或毒性，以及工艺颠倒。该项目基于关于这些过程的两个假设：__大多数消化器中的醋解甲烷生成主要由低umax、低Ks的微生物(例如甲烷菌)主导，导致消化器几乎没有储备能力来使用醋酸盐。__颗粒有机物的转化，通过分解或水解和发酵产生醋酸酯，以高初始速率发生，这可以设法选择具有更高生长和醋酸酯转化率的微生物。

0332118 Ferguson Digestion involves a complex microbial community with sequential conversion of substrates and interdependencies among the populations. The disintegration and hydrolysis of particulate organics has often been thought to limit overall solids degradation in digestion, and methane production from acetate has long been linked to process stability. These processes are directly connected because hydrolysis and fermentation produce acetate and acetate-using (acetoclastic) methanogens consume it. The rate of production can exceed the rate of consumption leading to acetate (and other short chain fatty acids) accumulation, decreases in pH, to inhibition or toxicity, and to process upset. The project is based on two hypotheses about these processes:__ Acetoclastic methanogenesis in most digesters is dominated by low u max, low Ks microbes (e.g. Methanosaeta), resulting in digesters with little reserve capacity to use acetate.__ Conversion of particulate organics, which produces acetate via disintegration or hydrolysis and fermentation, occurs at high initial rates, which can be managed to select for microbes with much higher growth and acetate conversion rates.