%A Yulun Nie, Xike Tian, Zhaoxin Zhou, Yu-You Li %T Impact of food to microorganism ratio and alcohol ethoxylate dosage on methane production in treatment of low-strength wastewater by a submerged anaerobic membrane bioreactor %0 Journal Article %D 2017 %J Front. Environ. Sci. Eng. %J Frontiers of Environmental Science & Engineering %@ 2095-2201 %R 10.1007/s11783-017-0947-1 %P 6- %V 11 %N 6 %U {https://journal.hep.com.cn/fese/EN/10.1007/s11783-017-0947-1 %8 2017-12-25 %X

Efficient methane recovery was obtained when the F/M ratio was below 0.357.

AE was efficiently degraded and converted into CH 4 by anaerobic microbes.

Microbe could cope with the stress of AE by producing more EPS and SMP.

F/M ratio of 1.054 decrease the methane production potential significantly.

The methane production activity of sludge was inhibited at a higher AE dosage.

The effects of food to microorganism (F/M) ratio and alcohol ethoxylate (AE) dosage on the methane production potential were investigated in treatment of low-strength wastewater by a submerged anaerobic membrane bioreactor (SAnMBR). The fate of AE and its acute and/or chronic impact on the anaerobic microbes were also analyzed. The results indicated that AE had an inhibitory effect to methane production potential (lag-time depends on the AE dosage) and the negative effect attenuated subsequently and methane production could recover at F/M ratio of 0.088–0.357. VFA measurement proved that AE was degraded into small molecular organic acids and then converted into methane at lower F/M ratio (F/M<0.158). After long-term acclimation, anaerobic microbe could cope with the stress of AE by producing more EPS (extracellular polymeric substances) and SMP (soluble microbial products) due to its self-protection behavior and then enhance its tolerance ability. However, the methane production potential was considerably decreased when AE was present in wastewater at a higher F/M ratio of 1.054. Higher AE amount and F/M ratio may destroy the cell structure of microbe, which lead to the decrease of methane production activity of sludge and methane production potential.