颗粒活性炭电极耦联间歇供电强化城镇有机固废厌氧产甲烷  

Enhancing Anaerobic Methanogenesis of Urban Organic Solid Waste by Granular Activated Carbon-supplemented Electrodes Coupled with Intermittent Power Supply

作　　者：潘佳禹 李美 李杨[1] PAN Jiayu;LI Mei;LI Yang(School of Chemical Engineering,Ocean and Life Sciences,Dalian University of Technology,Panjin Liaoning 124221;School of Environment,Dalian University of Technology,Dalian Liaoning 116024)

机构地区：[1]大连理工大学化工海洋与生命学院,辽宁盘锦124221 [2]大连理工大学环境学院,辽宁大连116024

出　　处：《环境卫生工程》2025年第2期42-49,54,共9页Environmental Sanitation Engineering

基　　金：国家重点研发计划子课题(2023YFD1701405-01)。

摘　　要：直接种间电子传递(DIET)对扩散传质依赖低,在含固率高、氨氮胁迫的城镇有机固废厌氧消化工程中,可以作为额外的产甲烷途径。然而,已知能参与DIET的电营养型产甲烷菌不具备导电菌毛或外膜细胞色素,胞外电子需跨越电惰性的细胞膜进入胞内,才能参与CO_(2)还原过程。有研究表明,低压电刺激可改善膜结合蛋白的导电性,但效果主要集中在阴极富集的生物膜,且持续供电会造成能耗过高,不利于大规模工程化应用。本研究将颗粒活性炭填充电极与间歇供电耦联,探究其对城镇有机固废厌氧消化性能的影响。研究结果表明:颗粒活性炭填充电极能够将电场影响从阴极拓展至其表面,使产甲烷能力提高了26%;通过循环伏安扫描利用Randles-Ševčík方程计算微生物膜的电子转移系数,发现活性炭表面微生物相比反应器中污泥提高1倍以上;活性炭在间歇供电时能够保留部分电场影响,闭路运行阶段活性炭表面生物膜对扫描电化学显微镜和电化学傅里叶红外光谱的电信号响应更强;通过微生物群落分析发现,投加颗粒活性炭作填充电极能够富集更多和DIET相关的产甲烷古菌,如Methanospirillum在活性炭上的相对丰度(39.86%)远高于对照组(21.45%)。活性炭耦联间歇供电时,开路运行使Methanospirillum的相对丰度从39.86%降低至25.84%。Direct interspecies electron transfer(DIET)has a low dependence on diffusive mass transfer.In anaerobic digestion projects of urban organic solid waste with high solid content and ammonia nitrogen stress,DIET can serve as an additional methanogenic pathway.However,electroautotrophic methanogens that are known to participate in DIET lack conductive pili or outer membrane cytochromes,and extracellular electrons must cross the electrically inert cell membrane to enter the cell interior and participate in the CO₂reduction process.Studies have shown that low-voltage electrical stimulation can improve the conductivity of membrane-bound proteins,but the effect is mainly concentrated in the biofilm enriched at the cathode,and continuous power supply will lead to excessive energy consumption,which is not conducive to large-scale engineering applications.In this study,granular activated carbon(GAC)was used as a packing material in the electrode coupled with intermittent power supply to investigate its impact on the anaerobic digestion performance of urban organic solid waste.The results showed that the GAC-packed electrode could extend the influence of the electric field from the cathode to its surface,increasing the methanogenic capacity by 26%.Cyclic voltammetry scanning was used in combination with the Randles-Ševčík equation to calculate the electron transfer coefficient of the microbial film,and it was found that the microbial film on the GAC surface had more than double the electron transfer coefficient compared to the sludge in the reactor.During intermittent power supply,GAC could retain some of the electric field’s influence,and in the closed-circuit operation phase,the biofilm on the GAC surface had a stronger electrical signal response to scanning electrochemical microscopy and electrochemical Fourier transform infrared spectroscopy.Microbial community analysis revealed that adding GAC as a packing material in the electrode could enrich more methanogenic archaea related to DIET,for example,the relative ab

关 键 词：城镇有机固废 厌氧消化 直接种间电子传递 间歇供电 颗粒活性炭填充电极 

分 类 号：X799.3[环境科学与工程—环境工程] X703