Graduate School of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan.
Graduate School of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan.
Bioresour Technol. 2020 Oct;314:123775. doi: 10.1016/j.biortech.2020.123775. Epub 2020 Jul 2.
This study investigated the synergistic effects of rice straw (RS) and rice bran (RB) addition on methane production and process stability of anaerobic digestion of food waste (FW). Positive synergistic effect (Synergy index (SI) = 1.03-1.24 > 1) was noticed in all the co-digestion reactors. The optimum mixing ratio of FW:RS:RB (volatile solid (VS) basis) was 60:10:30 with the maximum SI (1.24), achieving 27.4% increase in methane yield (235.4 mL/g-VS) and around 5 days shorter of λ (3.7 days) compared to the mono-digestion of FW (184.8 mL/g-VS and 8.2 days). Remarkably high concentration of volatile fatty acids (VFAs) was also accumulated in the mono-digestion of FW, especially propionic acid, which to a great extent caused the methane production to stagnate. Results from this study demonstrate that co-digestion of FW and RS with RB has high potentials for energy recovery from AD of the mixed feedstocks and its stable operation.
本研究考察了稻草（RS）和米糠（RB）添加对食物垃圾（FW）厌氧消化产甲烷和过程稳定性的协同作用。在所有共消化反应器中都观察到了正协同效应（协同指数（SI）= 1.03-1.24>1）。FW:RS:RB（挥发性固体（VS）基础）的最佳混合比为 60:10:30，最大 SI（1.24），与 FW 的单消化相比，甲烷产量（235.4 mL/g-VS）增加了 27.4%，λ（3.7 天）缩短了约 5 天（184.8 mL/g-VS 和 8.2 天）。FW 的单消化也积累了大量的挥发性脂肪酸（VFAs），特别是丙酸，这在很大程度上导致了甲烷产量的停滞。本研究结果表明，FW 和 RS 与 RB 的共消化具有从混合原料的 AD 中回收能源并实现其稳定运行的巨大潜力。
