颗粒活性炭促进高温厌氧消化的研究

近年来的研究表明，颗粒活性炭（GAC）可以通过种间电子传递（DIET）过程，来提高中温厌氧消化（MAD）产甲烷.然而，GAC是否能够提高高温厌氧消化（TAD）产甲烷，以及其促进产甲烷原理尚不明确.通过乙酸钠为基质的批试验研究了投加GAC对高温消化产甲烷的影响.批试验结果表明GAC的加入促进了高温消化效果.定量PCR结果表明GAC的加入对生物量的贡献微小，说明促进效果可能不是通过生物量实现的.高通量测序结果发现高温下添加GAC富集了Thermodesulfolbiaceae，Anaerobaculaceae，以及古菌Methanosacinacea.该研究推测GAC的促进作用可能与直接种间电子传递有关.

The study on granular activated carbon to promote thermophilic anaerobic digestion

Recent studies have suggested that granular activated carbon (GAC) could improve the methane production from mesophilic anaerobic digestion (MAD) by facilitating direct interspecies electron transfer (DIET). However, it is unclear whether the involvement of GAC could enhance methane production from thermophilic anaerobic digestion (TAD) and its roles in stimulating methane production have not been clarified. Here, the effect of GAC addition on methane production from TAD was studied through batch experiments with sodium acetate as substrate. The results indicated that the utilization of GAC significantly promoted the TAD process. But, through estimating the microbial biomass with quantitative PCR, it was revealed that the contribution of GAC to the microbial biomass is tiny. This may imply that the enhancing methane production by GAC is not achieved by increasing the amount of biomass. Moreover, significant alterations in microbial community structure were detected between reactors with and without GAC through high-throughput sequencing. In presence of GAC, Thermodesulfolbiaceae, Anaerobaculaceae and Methanosacinacea were enriched/dominant. Thus, it is proposed that, in the TAD process, GAC may play a role in the enrichment of specific species and accelerate the newly formed DIET pathway mediated by thermophilic microbiota.