State Key Laboratory of Pollution Control and Resources Reuse, School of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai, 200092, China; Beijing Center for Environmental Pollution Control and Resources Recovery, Beijing University of Chemical Technology, Beijing, 100029, China.
State Key Laboratory of Pollution Control and Resources Reuse, School of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai, 200092, China.
J Environ Manage. 2024 Nov;370:123041. doi: 10.1016/j.jenvman.2024.123041. Epub 2024 Oct 28.
This experiment reports an energy-saving, cost-effective and environmental-friendly method to recover energy from high-cellulose waste: anaerobic digestion (AD) by extending hydraulic residence time (HRT) from 50d to 70d with ultra-high organic loading rate (OLR) of 2.28-2.80 g TS·L d. The results indicate that biogas yield per VS and methane yield per VS increase with the extended HRT, with a maximum increase of up to 67.9%, while both yields decrease as OLR increases. The volumetric gas production (VGP) and volumetric methane production (VMP) improve by 20.2-37.3% when HRT is extended to 57 days and OLR is 2.80 g TS·L d, reaching a peak at this point. As the biogas production capacity of the two-stage anaerobic digestion reaches its peak, the gap between the one-stage system and the two-stage system decreases from 23% to 7% under the same conditions. This demonstrates that optimizing HRT and OLR not only enhance the gas production efficiency of the AD system but also reduce the gas production disparity between single-stage and two-stage systems, thus serving as a cost-effective method for engineering operations. Microbial community analysis of each system reveals that extending HRT increases the abundance and diversity of microbial communities, while changes in HRT and OLR result in significant shifts in the distribution of methanogens. Through reasonable regulation of HRT and OLR, a balance can be found between the full degradation of organic matter and the system load, so as to maximize biogas production and efficiency.
本实验报道了一种从富含纤维素的废物中回收能源的节能、经济且环保的方法：通过将水力停留时间（HRT）从 50 天延长至 70 天，并采用超高有机负荷率（OLR）2.28-2.80 g TS·L·d-1，实现了厌氧消化（AD）。结果表明，沼气产率（VS 基础）和甲烷产率（VS 基础）随 HRT 的延长而增加，最大增幅高达 67.9%，而随着 OLR 的增加，两种产率均呈下降趋势。当 HRT 延长至 57 天且 OLR 为 2.80 g TS·L·d-1 时，体积产气率（VGP）和体积甲烷产率（VMP）提高了 20.2-37.3%，达到峰值。随着两段式厌氧消化的沼气产生能力达到峰值，在相同条件下，一段式系统和两段式系统之间的差距从 23%缩小到 7%。这表明，优化 HRT 和 OLR 不仅可以提高 AD 系统的产气效率，还可以减少单级和两级系统之间的产气差异，从而成为一种经济有效的工程操作方法。对每个系统的微生物群落分析表明，延长 HRT 会增加微生物群落的丰度和多样性，而 HRT 和 OLR 的变化会导致产甲烷菌的分布发生显著变化。通过合理调节 HRT 和 OLR，可以在有机物的完全降解和系统负荷之间找到平衡，从而最大限度地提高沼气产量和效率。
