The role of hydraulic retention time on controlling methanogenesis and homoacetogenesis in biohydrogen production using upflow anaerobic sludge blanket (UASB) reactor and packed bed reactor (PBR)

摘要: Abstract Methanogenesis and homoacetogenesis are two notorious hydrogen-consuming reactions during dark fermentation for biohydrogen production. The focus of this study was on the role hydraulic retention time (HRT) to control methanogenesis in an upflow anaerobic sludge blanket (UASB) reactor a packed bed (PBR). HRT changed from 24 4 h 2 h UASB PBR, respectively. A maximal hydrogen yield 1.47 mol/mol glucoseadded with high production rate 4.38 L/L/d achieved at 8 h UASB. In comparison, 0.89 mol/mol 10.66 L/L/d PBR. With reduction HRT, volumic consumption due decreased 12.1 3.1%. As value reduced 66.9 31.4%. Homoacetogenesis PBR dramatically suppressed when 8 4 h, However, these microbes cannot be completely removed. Microbial diversity analysis using Illumina MiSeq sequencing revealed existence Clostridium ljungdahlii, homoacetogen, low HRT. addition, relative abundance Clostridiaceae accelerated proliferation lactic acid producers ethanol which were mainly families Ruminococcaceae Leuconostocaceae.