Enhancing anaerobic digestion of food waste with carbon-based conductive materials
Promoting direct interspecies electron transfer (DIET) with conductive materials is known to accelerate and stabilize methane production from simple substrates,such as ethanol and organic acids,but the possibility of enhancing the conversion of more complex wastes to methane with a similar strategy is less certain.Therefore,the methanogenic metabolism of dog food,a food waste surrogate,was investigated in laboratory-scale anaerobic digesters with different carbon-based conductive materials and polyester cloth,or no additions,as controls.The digesters were operated in two modes: semi-continuous mode and batch mode.In semi-continuous mode,carbon cloth and granular activated carbon (GAC) all permitted higher organic loading rates and promoted faster recovery of soured reactors than the control reactors.Analysis of 16S rRNA gene sequences revealed that on the surface of the carbon cloth there was a specific and substantial enrichment of Sporanaerobacter species,which may have the ability to metabolize fermentable substrates with extracellular electron transfer;and Methanosarcina species,which are known to participate in DIET with carbon cloth as the electron transport mediator.The results suggest that the carbon cloth facilitated metabolism of fermentable substrates with DIET to Methanosarcina species and demonstrate that promoting DIET can improve the conversion of complex organic wastes to methane.In batch mode,digesters with carbon cloth or granular activated carbon (GAC) significantly improved the conversion of dry food waste to methane even in the presence of extremely high VFA concentrations (~500 mM).In the batch mode system,DIET did not appear to be a significant metabolism from the microbial community analysis,however,conductive materials did seem to stimulate the growth of bacteria and methanogens known to form syntrophic partnerships that can enhance anaerobic digestion processes.
Anaerobic digestion food waste methanogenesis direct interspecies electron transfer carbon-based conductive materials
Yan Dang Dezhi Sun Kelly P Nevin Dawn E.Holmes Derek R.Lovley
Beijing Key Laboratory for Source Control Technology of Water Pollution, College of Environmental Sc Beijing Key Laboratory for Source Control Technology of Water Pollution, College of Environmental Sc Department of Microbiology, University of Massachusetts Amherst, Morril Ⅳ N Science Center, Amherst,
国际会议
The 15th IWA World Conference on Anaerobic Digestion( 第15届IWA世界厌氧大会)
北京
英文
550-554
2017-10-17（万方平台首次上网日期，不代表论文的发表时间）