Full-scale demonstration of step feed concept for improving an anaerobic/anoxic/aerobic nutrient removal process.
A small wastewater treatment plant (WWTP) failed to meet effluent requirements of the first-A discharge standard in China, with the anaerobic/anoxic/oxic (A/A/O) process treating municipal and partial industrial wastewater. Thus an A/O step feed process (Anoxic/oxic/anoxic/oxic/anoxic/oxic) with floating plastic carriers in aerobic units was proposed to improve nutrient removal within the existing WWTP. Four main reform strategies were applied: (1) the original influent was divided into three streams which led into corresponding anoxic units; (2) floating plastic carriers were placed in the second and third oxic units; (3) nitrified liquid recycling was omitted; (4) channel shapes and sizes were adjusted between adjacent units to prevent backflow. After these modifications were implemented, the total nitrogen and phosphorus concentrations in the effluent were reduced from 20.8 to 14.2mg/L, and from 1.89 to 0.57 mg/L, respectively. Moreover, annual electricity consumption in the WWTP was reduced by 245 MWh as a result of these modifications.
Key Laboratory of Beijing Water Quality Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing 100124, China. geshijian1221@126.com
Shijian
S
Ge
Yunpeng
Y
Zhu
Congcong
C
Lu
Shuying
S
Wang
Yongzhen
Y
Peng
D000332:Aerobiosis; D000693:Anaerobiosis; D001673:Biodegradation, Environmental; D057919:Biological Oxygen Demand Analysis; D019149:Bioreactors / Q000382:microbiology; D002681:China; D009584:Nitrogen / Q000302:isolation & purification; D010758:Phosphorus / Q000302:isolation & purification; D000644:Quaternary Ammonium Compounds / Q000302:isolation & purification; D012722:Sewage / Q000382:microbiology; D014865:Waste Disposal, Fluid; D062065:Wastewater / Q000737:chemistry; D014874:Water Pollutants, Chemical / Q000302:isolation & purification*; D018508:Water Purification / Q000191:economics / Q000379:methods*
D009584:Nitrogen; D010758:Phosphorus; D000644:Quaternary Ammonium Compounds; D012722:Sewage; D062065:Wastewater; D014874:Water Pollutants, Chemical