Granular activated carbon (GAC) has been reported to benefit anaerobic digestion systems by stimulating direct interspecies electron transfer (DIET) as an alternative to interspecies hydrogen transfer (IHT). Conventional up-flow anaerobic sludge blanket (UASB) reactors typically have GAC settled at the bottom of the reactor, limiting the contact between biomass and GAC. This study demonstrated a modified UASB reactor that fluidizes GAC by encaging GAC in plastic carriers. Enhanced performance was achieved with respect to methane production and COD removal at an organic loading rate of 1500 g COD/m³/d under the temperature of 20 ^oC using the self-fluidized GAC configuration; with the methanation rate increased from 0.33 ± 0.08 g CH₄-COD/g influent COD in the non-GAC reactor, to 0.66 ± 0.02 g CH₄-COD/g influent COD in the GAC-only reactor, and further increased to 0.77 ± 0.02 g CH₄-COD/g influent COD in the self-fluidized GAC reactor. The concentrations of medium-chain acyl-homoserine lactones increased in the GAC-amended reactors, potentially associated with the promotion of syntrophic interactions between bacteria and archaea. Batch tests were performed for syntrophic propionate degradation under hydrogen-inhibition conditions, and showed that microbial consortium enriched in both GAC amended reactors can overcome hydrogen inhibition. Further microbial community analysis unveiled a variation in spatial distribution in the GAC enriched microbial consortium (including DIET indicator microorganisms such as Geobacter and Methanosarcina) based on the location of GAC in the reactors. This study demonstrated an improved GAC amendment strategy in UASB reactors to facilitate biomethane recovery from wastewater anaerobic digestion.

据报道，通过刺激直接种间电子转移（DIET）作为种间氢转移（IHT）的替代方法，颗粒活性炭（GAC）有益于厌氧消化系统。常规的上流式厌氧污泥层（UASB）反应器通常将GAC沉淀在反应器底部，从而限制了生物质与GAC之间的接触。这项研究证明了一种改良的UASB反应器，该反应器通过将GAC夹在塑料载体中而使GAC流化。使用自流化GAC配置，在20 ^o C的温度下以1500 g COD / m ³ / d的有机负荷速率获得的甲烷生产和COD去除性能得到增强；甲烷化率从0.33±0.08 g CH _4增加-COD /克进水COD在非GAC反应器中，以0.66±0.02克CH ₄ -COD /克进水COD在GAC-只反应器中，并进一步增加至0.77±0.02克CH ₄ -COD /克进水COD在自流化GAC反应器。在GAC修正的反应器中，中链酰基高丝氨酸内酯的浓度增加，这可能与促进细菌和古细菌之间的营养性相互作用有关。在氢抑制条件下进行了对营养性丙酸降解的分批测试，结果表明，在两个GAC修正反应器中富集的微生物联合体都可以克服氢抑制作用。进一步的微生物群落分析揭示了富含GAC的微生物联盟（包括DIET指示微生物如根据GAC在反应堆中的位置确定了Geobacter和Methanosarcina）。这项研究表明，UASB反应器中的GAC修正策略得到了改进，以促进废水厌氧消化过程中生物甲烷的回收。