Oxygen tolerance capacity of upflow anaerobic solid-state (UASS) with anaerobic filter (AF) system
Yao Meng
,
Carsten Jost
,
Jan Mumme
,
Kaijun Wang
,
Bernd Linke
DOI:10.1016/j.jes.2016.01.009
Received November 12, 2015,Revised January 18, 2016, Accepted January 21, 2016, Available online February 16, 2016
Volume 28,2016,Pages 200-206
In order to investigate the oxygen tolerance capacity of upflow anaerobic solid-state (UASS) with anaerobic filter (AF) system, the effect of microaeration on thermophilic anaerobic digestion of maize straw was investigated under batch conditions and in the UASS with AF system. Aeration intensities of 0–431 mL O2/gvs were conducted as pretreatment under batch conditions. Aeration pretreatment obviously enhanced anaerobic digestion and an aeration intensity of 431 mL O2/gvs increased the methane yield by 82.2%. Aeration intensities of 0–355 mL O2/gvs were conducted in the process liquor circulation of the UASS with AF system. Dissolved oxygen (DO) of UASS and AF reactors kept around 1.39 ± 0.27 and 0.99 ± 0.38 mg/L, respectively. pH was relatively stable around 7.11 ± 0.04. Volatile fatty acids and soluble chemical oxygen demand concentration in UASS reactor were higher than those in AF reactor. Methane yield of the whole system was almost stable at 85 ± 7 mL/gvs as aeration intensity increased step by step. The UASS with AF system showed good oxygen tolerance capacity.
