Article
Engineering, Environmental
Naveen Chand, Kapil Kumar, Surindra Suthar
Summary: The study demonstrated that intermittent aeration in VFCWs significantly improved the removal efficiency of COD, NH4+-N, NO3-N, and TP compared to non-aerated setups, while setups with biochar (BC) addition and plantation were more advantageous in nutrient removal than those without BC. Moreover, the COD/N ratio of wastewater did not have a significant impact on VFCWs with BC and intermittent aeration, indicating the effectiveness of slow adsorption and fast aerobic degradation processes.
JOURNAL OF WATER PROCESS ENGINEERING
(2021)
Article
Environmental Sciences
Yi Wang, Wen-Huai Wang, Heng Zhang, Fei-Long Yan, Jia-Jun Li
Summary: The study found that successful removal of organic matter and nitrogen can be achieved in wetlands with partial-area aeration by using intermittent aeration strategy, which can also enhance the conversion rate of ammonia nitrogen, maintain a stable dissolved oxygen concentration, and ensure the accumulation rate of nitrite.
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
(2021)
Article
Environmental Sciences
A. Pascual, J. A. Alvarez, D. de la Varga, C. A. Arias, D. Van Oirschot, R. Kilian, M. Soto
Summary: The influence of bed depth on the performance of aerated horizontal constructed wetlands was investigated at the pilot plant scale. The results showed that a larger bed depth and artificial aeration can improve the loading rate and the removal efficiency of organic matter and nitrogen in the horizontal constructed wetlands.
SCIENCE OF THE TOTAL ENVIRONMENT
(2024)
Article
Engineering, Environmental
Yuanyuan Miao, Liang Zhang, Deshuang Yu, Jianhua Zhang, Wenke Zhang, Guocheng Ma, Xinchao Zhao, Yongzhen Peng
Summary: Intermittent aeration is an effective strategy for biological wastewater treatment, allowing for advanced nitrogen removal and reduced energy consumption. It is suitable for partial nitrification and denitrification processes.
CHEMICAL ENGINEERING JOURNAL
(2022)
Article
Environmental Sciences
Huoqing Wang, Jia Miao, Yuepeng Sun
Summary: This study compared nitrogen removal and N2O emissions from lab-scale anoxic/aerobic sequencing batch reactor (AOSBR) and intermittent aeration sequencing batch reactor (IASBR), finding that IASBR showed enhanced nitrogen removal efficiency and lower N2O emission factors compared to AOSBR. N2O emissions were significantly higher during simultaneous nitrification and denitrification (SND) compared to aerobic nitrification and denitrification, with different emission factors for oxidized ammonium in each phase.
ENVIRONMENTAL TECHNOLOGY
(2022)
Article
Environmental Sciences
Liya Li, Jingwei Feng, Liu Zhang, Hao Yin, Chunli Fan, Zechun Wang, Menglei Zhao, Chengchang Ge, Hao Song
Summary: The study revealed significant differences in nitrogen and phosphorus removal efficiency of subsurface flow constructed wetlands (SFCWs) filled with different substrates. Intermittent aeration improved nitrogen and phosphorus removal efficiencies of SFCWs, with the front section being the main pollutant removal area. Precipitation and adsorption on substrates were identified as the main mechanisms for phosphorus removal.
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
(2021)
Article
Environmental Sciences
Manping Zhang, Jung-Chen Huang, Shanshan Sun, Muhammad Muneeb Ur Rehman, Shengbing He, Weili Zhou
Summary: Constructed wetlands are effective in removing nitrogen from water, with potential activities of DNRA, anammox, denitrification, and nitrification contributing to nitrogen removal. Planted mesocosms showed better performance in nitrogen removal compared to unplanted mesocosms, with higher values of potential activities of nitrogen-cycling pathways observed in the planted mesocosms.
SCIENCE OF THE TOTAL ENVIRONMENT
(2021)
Article
Engineering, Environmental
Leslie Behrends, Laura Houke, Earl Bailey, Pat Jansen
Summary: A microcosm treatability study was conducted in a wetland research facility in the USA. The study found that wastewater treatment with reciprocation significantly improved removal of COD and ammonium.
WATER SCIENCE AND TECHNOLOGY
(2022)
Article
Engineering, Environmental
Yu Lei, Thomas Wagner, Huub Rijnaarts, Vinnie de Wilde, Alette Langenhoff
Summary: This study aimed to improve the removal of micropollutants (MPs) in constructed wetlands (CWs) by optimizing the design of batch-operated CWs, and found that using bark-biochar as a support matrix significantly increased the removal of MPs compared to traditional sand-filled CWs.
Article
Environmental Sciences
Elackiya Sithamparanathan, Nora B. Sutton, Huub H. M. Rijnaarts, Katarzyna Kujawa-Roeleveld
Summary: Discharge of nitrogen with wastewater causes eutrophication in surface water, but nutrient-rich wastewater can be valuable for agriculture. Tailoring N removal or conservation is important to meet the requirements of different water end uses. Improved vertical flow constructed wetlands with pumice as substrata showed the highest TN removal at both COD/N ratios.
Article
Agricultural Engineering
Susan N. James, Arya Vijayanandan
Summary: An anoxic-aerobic-anoxic process was established in a sequencing batch reactor to simultaneously remove organic carbon and nitrogen from wastewater. The study found that the optimum conditions for the process were achieved with a dissolved oxygen level of 1.5 mg/L and 1 hour pre-anoxic and post-anoxic periods. Under these conditions, the removal efficiencies of TOC, NH4+-N, and TN were 98.76%, 98.52%, and 88.23% respectively. Breakpoints in the pH, DO, and ORP curves provided insights into the biochemical reactions occurring in the reactor. Inhibition studies revealed that nitrogen removal pathways such as heterotrophic nitrification or direct conversion contributed to the removal of 27.69% of NH4+-N, while aerobic denitrification accounted for the removal of 20.55% of TN. Microbial community analysis confirmed the presence of heterotrophic nitrifiers and aerobic denitrifiers. The study emphasized the benefits of the varied redox conditions provided by limited aeration for nitrogen removal, leading to reduced energy usage and operating costs.
BIORESOURCE TECHNOLOGY
(2022)
Article
Engineering, Environmental
Jie Wang, Ling Xia, Jieyu Chen, Xiaoning Wang, Hu Wu, Dapeng Li, George F. Wells, Jun Yang, Jie Hou, Xugang He
Summary: This study demonstrated the feasibility of achieving phosphorus removal through enhanced biological phosphorus removal (EBPR) in an intermittent aeration constructed wetland (CW). The integration of EBPR with simultaneous nitrification-endogenous denitrification (SNED) significantly improved phosphorus and nitrogen removal efficiency, providing a novel approach for advanced nutrient removal in CWs.
CHEMICAL ENGINEERING JOURNAL
(2021)
Article
Environmental Sciences
Tang Liu, Shufeng Liu, Shishi He, Zhichao Tian, Maosheng Zheng
Summary: Intermittent aeration in wastewater treatment can enhance total nitrogen removal efficiency, decrease N2O emission, and promote quick nitrification-denitrification processes.
Review
Biotechnology & Applied Microbiology
Aakanksha Rampuria, Niha Mohan Kulshreshtha, AkhilendraBhushan Gupta, Urmila Brighu
Summary: Traditional nitrogen transformation processes in constructed wetlands involve aerobic nitrification and anoxic denitrification, but recent research has discovered novel pathways like anaerobic ammonium oxidation, heterotrophic nitrification, and aerobic denitrification, which can be enhanced by enriching specialized bacteria through selection pressures. Understanding these novel pathways and associated microbial populations can provide new insights for designing constructed wetlands for enhanced nitrogen removal.
WORLD JOURNAL OF MICROBIOLOGY & BIOTECHNOLOGY
(2021)
Article
Environmental Sciences
Linlin Li, Jing Zhang, Qiuyue Shi, Shaoyong Lu
Summary: To compare the effect of different oxygen supply strategies on nitrogen removal in constructed wetlands, tidal flow constructed wetlands (TFCWs) and intermittently aerated constructed wetlands (IACWs) were investigated. Results showed that IACWs had high removal efficiencies for NH4+-N and COD, while TFCWs showed higher efficiency for total nitrogen removal due to enhanced nitrification and denitrification. The bacterial communities in TFCWs were enriched with key genera related to nitrogen transformation, while IACWs had a more complex and robust community structure.
