title: An efficient process for wastewater treatment to mitigate free nitrous acid generation and its inhibition on biological phosphorus removal.
abstract: Free nitrous acid (FNA), which is the protonated form of nitrite and inevitably produced during biological nitrogen removal, has been demonstrated to strongly inhibit the activity of polyphosphate accumulating organisms (PAOs). Herein we reported an efficient process for wastewater treatment, i.e., the oxic/anoxic/oxic/extended-idle process to mitigate the generation of FNA and its inhibition on PAOs. The results showed that this new process enriched more PAOs which thereby achieved higher phosphorus removal efficiency than the conventional four-step (i.e., anaerobic/oxic/anoxic/oxic) biological nutrient removal process (41 ± 7% versus 30 ± 5% in abundance of PAOs and 97 ± 0.73% versus 82 ± 1.2% in efficiency of phosphorus removal). It was found that this new process increased pH value but decreased nitrite accumulation, resulting in the decreased FNA generation. Further experiments showed that the new process could alleviate the inhibition of FNA on the metabolisms of PAOs even under the same FNA concentration.
authors.affiliation: 1] College of Environmental Science and Engineering, Hunan University, Changsha 410082, China [2] Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, China.
authors.forename: Jianwei
authors.initials: J
authors.lastname: Zhao
authors.affiliation: 1] College of Environmental Science and Engineering, Hunan University, Changsha 410082, China [2] Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, China [3] State Key Laboratory of Pollution Control and Resources Reuse, School of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092, China [4] Advanced Water Management Centre, The University of Queensland, QLD 4072, Australia [5] Jiangsu Tongyan Environmental Production Science and Technology Co. Ltd., Yancheng. 224000, China.
authors.forename: Dongbo
authors.initials: D
authors.lastname: Wang
authors.affiliation: 1] College of Environmental Science and Engineering, Hunan University, Changsha 410082, China [2] Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, China.
authors.forename: Xiaoming
authors.initials: X
authors.lastname: Li
authors.affiliation: 1] College of Environmental Science and Engineering, Hunan University, Changsha 410082, China [2] Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, China.
authors.forename: Qi
authors.initials: Q
authors.lastname: Yang
authors.affiliation: 1] College of Environmental Science and Engineering, Hunan University, Changsha 410082, China [2] Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, China.
authors.forename: Hongbo
authors.initials: H
authors.lastname: Chen
authors.affiliation: 1] College of Environmental Science and Engineering, Hunan University, Changsha 410082, China [2] Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Zhong
authors.affiliation: 1] College of Environmental Science and Engineering, Hunan University, Changsha 410082, China [2] Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, China.
authors.forename: Hongxue
authors.initials: H
authors.lastname: An
authors.affiliation: 1] College of Environmental Science and Engineering, Hunan University, Changsha 410082, China [2] Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, China.
authors.forename: Guangming
authors.initials: G
authors.lastname: Zeng
mesh_terms: D011232:Chemical Precipitation; D006863:Hydrogen-Ion Concentration; D009608:Nitrous Acid / Q000737:chemistry* / Q000302:isolation & purification; D010084:Oxidation-Reduction; D011122:Polyphosphates / Q000302:isolation & purification* / Q000378:metabolism; D062065:Wastewater / Q000032:analysis* / Q000737:chemistry; D018508:Water Purification
chemical_list: D009608:Nitrous Acid; D011122:Polyphosphates; D062065:Wastewater