Abstract
The airlift internal circulation reactor for partial nitrification-anammox (PNA-ALR) has the advantages of a small footprint, high mass transfer efficiency, and the ease of formation of granular sludge, thus making it an effective biological treatment for ammonia-containing wastewater. Although superficial gas velocity (SGV) is an essential parameter for PNA-ALR, it is unclear how the magnitude of SGV impacts nitrogen removal performance. In this study, the nitrogen removal efficiencies of five PNA-ALRs with different SGV were measured during feeding with synthetic municipal wastewater. At an optimal SGV of 2.35 cm s-1, the PNA-ALR consistently maintained the total inorganic nitrogen (TIN) removal efficiency at 76.31% and the effluent TIN concentration was less than 10 mg L-1. By increasing or decreasing the SGV, the nitrogen removal efficiency decreased to a range between 30% and 50%. At lower SGV, the dead space in the PNA-ALR was increased by 21.15%, and the feast/famine ratio of sludge increased to greater than 0.5, which caused a disruption in the structure, and a large loss of, granular sludge. Computational fluid dynamics (CFD) simulations showed operation at a higher SGV, resulting in excessive shear stress of 3.25 N m-2 being generated from bubble rupture in the degassing section. Fluorescent staining determined a decrease of 26.5% in viable bacteria. These results have improved our understanding of the effects of SGV on a PNA-ALR during mainstream wastewater treatment.
Keywords
Airlift internal circulation bioreactor
Granular sludge
Mixing characteristics
Shear stress
Superficial gas velocity
MeSH 主题词
Anaerobic Ammonia Oxidation
Bioreactors/microbiology
Denitrification
Nitrification
Nitrogen
Oxidation-Reduction
Sewage/microbiology
Waste Disposal, Fluid
Wastewater
化学物质
Nitrogen
Sewage
Wastewater
作者与单位
共 8 位作者，点击展开单位 / ORCID
Zhang Xu
National Engineering Research Center of Industrial Wastewater Detoxication and Resource Recovery, East China University of Science and Technology, Shanghai, China; State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, School of Resources and Environmental Engineering, East China University of Science and Technology, Shanghai, China.
Zhao Wei-Qi
National Engineering Research Center of Industrial Wastewater Detoxication and Resource Recovery, East China University of Science and Technology, Shanghai, China; State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, School of Resources and Environmental Engineering, East China University of Science and Technology, Shanghai, China.
Yao Gen-Ji
National Engineering Research Center of Industrial Wastewater Detoxication and Resource Recovery, East China University of Science and Technology, Shanghai, China; State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, School of Resources and Environmental Engineering, East China University of Science and Technology, Shanghai, China.
Zhuang Jin-Long
Suzhou University of Science and Technology, School of Environmental Science and Engineering, Suzhou, China. Electronic address:
[email protected].
Liu Hong
Shanghai Huayi (Group) Company, Shanghai, China.
Gao Hui-Jie
SINOPEC (Dalian) Research Institute of Petroleum and Petrochemicals Company Limited, Dalian, China.
Liu Yong-Di
National Engineering Research Center of Industrial Wastewater Detoxication and Resource Recovery, East China University of Science and Technology, Shanghai, China; State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, School of Resources and Environmental Engineering, East China University of Science and Technology, Shanghai, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai, China.
Li Wei
National Engineering Research Center of Industrial Wastewater Detoxication and Resource Recovery, East China University of Science and Technology, Shanghai, China; State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, School of Resources and Environmental Engineering, East China University of Science and Technology, Shanghai, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai, China. Electronic address:
[email protected].
