Department of Civil and Environmental Engineering, American University of Beirut, Lebanon.
Bioresour Technol. 2012 Aug;117:63-71. doi: 10.1016/j.biortech.2012.02.125. Epub 2012 Mar 4.
This paper examines the effect of mixing on the performance of thermophilic anaerobic digestion of source-sorted organic fraction of municipal solid waste during the start-up phase and in the absence of an acclimated seed. For this purpose, two digesters were used under similar starting conditions and operated for 235 days with different mixing schemes. While both digesters exhibited a successful startup with comparable specific methane yield of 0.327 and 0.314 l CH4/g VS, continuous slow stirring improved stability by reducing average VFA accumulation from 2890 to 825 mg HAc/l, propionate content from 2073 to 488 mg/l, and VFA-to-alkalinity ratio from 0.32 to 0.07. As a result, the startup with slow mixing was faster and smoother accomplishing a higher loading capacity of 2.5 g VS/l/d in comparison to 1.9 g VS/l/d for non-mixing. Mixing equally improved microbial abundance from 6.6 to 10 g VSS/l and enhanced solids and soluble COD removal.
本文研究了混合对源分选城市固体废物有机部分在高温厌氧消化启动阶段和无驯化种子条件下的性能的影响。为此，在相似的起始条件下使用了两个消化器，并在不同的混合方案下运行了 235 天。虽然两个消化器都成功启动，比产甲烷量相当，分别为 0.327 和 0.314 l CH4/g VS，但连续缓慢搅拌通过将平均 VFA 积累从 2890 减少到 825 mg HAc/l，将丙酸含量从 2073 减少到 488 mg/l，以及 VFA-碱度比从 0.32 减少到 0.07，从而提高了稳定性。结果，与非混合相比，缓慢混合的启动更快、更平稳，实现了更高的负荷能力，达到 2.5 g VS/l/d，而非混合的为 1.9 g VS/l/d。混合同样提高了微生物丰度，从 6.6 增加到 10 g VSS/l，并增强了固体和可溶性 COD 的去除。
