Influence of phenol on ammonia removal in an intermittent aeration bioreactor treating biologically pretreated coal gasification wastewater
Chunyan Xu , Hongjun Han
,
Shengyong Jia
,
Qian Zhao
DOI:10.1016/j.jes.2015.08.013
Received May 26, 2015,Revised August 29, 2015, Accepted September 01, 2015, Available online November 29, 2015
Volume 28,2016,Pages 99-105
A laboratory-scale intermittent aeration bioreactor was investigated to treat biologically pretreated coal gasification wastewater that was mainly composed of NH3-N and phenol. The results showed that increasing phenol loading had an adverse effect on NH3-N removal; the concentration in effluent at phenol loading of 40 mg phenol/(L·day) was 7.3 mg/L, 36.3% of that at 200 mg phenol/(L·day). The enzyme ammonia monooxygenase showed more sensitivity than hydroxylamine oxidoreductase to the inhibitory effect of phenol, with 32.2% and 10.5% activity inhibition, respectively at 200 mg phenol/(L·day). Owing to intermittent aeration conditions, nitritation-type nitrification and simultaneous nitrification and denitrification (SND) were observed, giving a maximum SND efficiency of 30.5%. Additionally, ammonia oxidizing bacteria (AOB) and denitrifying bacteria were the main group identified by fluorescent in situ hybridization. However, their relative abundance represented opposite variations as phenol loading increased, ranging from 30.1% to 17.5% and 7.6% to 18.2% for AOB and denitrifying bacteria, respectively.
