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Wang P, Lu B, Chai X. Rapid start-up and long-term stable operation of the anammox reactor based on biofilm process: Status, challenges, and perspectives. CHEMOSPHERE 2023:139166. [PMID: 37295685 DOI: 10.1016/j.chemosphere.2023.139166] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Revised: 05/16/2023] [Accepted: 06/06/2023] [Indexed: 06/12/2023]
Abstract
Anammox-biofilm processes have great potential for wastewater nitrogen removal, as it overcomes the slow growth and easy loss of AnAOB (anaerobic ammonium oxidation bacteria). Biofilm carrier is the core part of the Anammox-biofilm reactor and plays a key role in the start-up and long-term operation of the process. Therefore, the research on the biofilm carrier of Anammox-based process was summarized and discussed in terms of configurations and types. In the Anammox-biofilm process, fixed bed biofilm reactor is a relatively mature biofilm carrier configuration and has advantages in terms of nitrogen removal and long-term operational stability, while moving bed biofilm reactor has advantages in terms of start-up time. Although the long-term operational stability of fluidized bed biofilm reactor is good, its nitrogen removal performance needs to be improved. Among the different biofilm carrier categories, the inorganic biofilm carrier has an advantage in start-up time, due to the enhancement of the growth and metabolic of AnAOB by inorganic materials (such as carbon and iron). Anammox-based reactors using organic biofilm carriers, especially suspension carriers, are well-established and more stable in long-term operation. Composite biofilm carriers combine the advantages of several materials, but their complex preparation procedures lead to high costs. In addition, possible research directions for accelerating the start-up and keeping the long-term stable operation of Anammox reactor by biofilm process were highlighted. It is hoped to provide a possible pathway for the rapid start-up of Anammox-based process, and references for the optimization and promotion of process.
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Affiliation(s)
- Pengcheng Wang
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai, 200092, China.
| | - Bin Lu
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai, 200092, China.
| | - Xiaoli Chai
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai, 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai, 200092, China.
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Morais RGD, Braga SM, Braga MCB. Evaluation of the start-up of hydraulic conditions of a fluidised bed system. ENVIRONMENTAL TECHNOLOGY 2022; 43:4029-4041. [PMID: 34092195 DOI: 10.1080/09593330.2021.1939794] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2021] [Accepted: 05/31/2021] [Indexed: 06/12/2023]
Abstract
The development of this research was based on the analysis of an anaerobic fluidised bed reactor from the assembly of its components to the sealing of the system and further fluidisation. A hydrometer and a Venturi were used to identify the best means of measuring the flow rate. Results produced by both devices were similar, however, the latter was less effective due to the low flow rates necessary to operate the system. The hydrometer was the most adequate device for flow rate measurements in the range between 0.1 and 1.0 m³/h, whereas the Venturi proved to be an adequate device for the flow in the range between 0.3 and 0.7 m³/h. Sand with grain sizes varying from 357 to 1000 µm was used as support material. It was not observed statistically significant differences between the minimum fluidisation velocities related to the amount of supported material of 20% and 40% (VSM/Vusable) added to the reactor. Forty percent of the usable volume occupied with sand is adequate to reach fluidisation, instead of only the expansion of the bed. The fluidisation velocities for the sand grain size of 357 µm were 8.4 m/h ± 0.25 for 20%, and 8.6 m/h ± 0.30 for 40%, whereas for the 505 µm they were, respectively for 20% and 40%, 9.2 m/h ±0.70 and 10.1 m/h ± 0.37. The hydraulic tests allow to stress that sand grain sizes varying from 357 to 505 µm are recommended to be used in a system with similar characteristics.
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Affiliation(s)
- Ricardo Gonçalves de Morais
- Department of Hydraulics and Sanitation, School of Engineering, Campus Polytechnic CentreParana Federal University, Curitiba, Brazil
| | - Sérgio Michelotto Braga
- Department of Hydraulics and Sanitation, School of Engineering, Campus Polytechnic CentreParana Federal University, Curitiba, Brazil
| | - Maria Cristina Borba Braga
- Department of Hydraulics and Sanitation, School of Engineering, Campus Polytechnic CentreParana Federal University, Curitiba, Brazil
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Enhanced Microbial Oxidation-Neutralization Treatment of Acid Mine Drainage Rich in Ferrous Ions (Fe 2+). INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:ijerph19116543. [PMID: 35682127 PMCID: PMC9180531 DOI: 10.3390/ijerph19116543] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Revised: 05/18/2022] [Accepted: 05/26/2022] [Indexed: 12/07/2022]
Abstract
In this work, a method of enhanced packed-bed microbial oxidation-neutralization has been employed to treat Fe2+-rich acid mine drainage. The method features the use of a large number of immobile Acidithiobacillus ferrooxidans (A. ferrooxidans) in a bioreactor to promote the oxidation of Fe2+ to Fe3+. Results show that when the influent Fe2+ concentration is about 900 mg/L and the Fe2+ oxidation efficiency tends to 100%, the maximum oxidation rate of Fe2+ in the bio-ceramsite, bio-volcanic stone, and bio-activated carbon packed columns are 301 mg/(L·h), 234 mg/(L·h), and 139 mg/(L·h), respectively. Compared with the direct neutralization method, the enhanced microbial oxidation-neutralization method has several advantages. Firstly, it oxidizes Fe2+ to Fe3+, directly neutralizing the acid mine drainage at low pH and reducing the consumption of neutralizer. Secondly, more economical CaCO3 can be used as neutralizer. Thirdly, it produces precipitates with high solid content (5.50%), good settling performance (SV30 = 4%), and small volume, and the capillary suction time (CST) is 8.9 s, which is easy to dehydrate.
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Study on Flow Characteristics of Bidirectional Sinusoidal Liquid Pulsed Gas-Liquid-Solid Multiphase Fluidized Bed. Chem Eng Res Des 2022. [DOI: 10.1016/j.cherd.2022.05.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Mohana AA, Farhad SM, Haque N, Pramanik BK. Understanding the fate of nano-plastics in wastewater treatment plants and their removal using membrane processes. CHEMOSPHERE 2021; 284:131430. [PMID: 34323805 DOI: 10.1016/j.chemosphere.2021.131430] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Revised: 06/20/2021] [Accepted: 07/01/2021] [Indexed: 06/13/2023]
Abstract
Nanoplastics (NPs) have become a major environmental issue due to their adverse effect on the water environment. Wastewater treatment plant (WWTP) is considered as one of the main sources for breaking down of larger-sized plastic debris and microplastics (MPs) into NPs. This study aims to provide a comprehensive understanding of NPs generation in the WWTPs, their physiochemical characteristics and interaction with the WWTPs. It is found that cracking is the major mechanism of plastics fragmentation in the WWTPs. This review also discusses the current membrane process used for NPs removal. It is found that conventional membrane processes are ineffective as they are not designed for NPs removal and fouling is a major obstacle for its application. Therefore, this study concludes by providing an outlook of developing a bio-nanofiltration process that can be used as a tertiary treatment for removing NPs and other components present in water. Such a process can produce NPs-free water for non-potable use or safe discharge into open waterways.
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Affiliation(s)
- Anika Amir Mohana
- Department of Applied Chemistry and Chemical Engineering, Islamic University, Kushtia, Bangladesh
| | - S M Farhad
- Department of Applied Chemistry and Chemical Engineering, Islamic University, Kushtia, Bangladesh
| | - Nawshad Haque
- CSIRO Mineral Resources, Clayton South, Melbourne, VIC, 3169, Australia
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Song Y, Liu Z, Chen H, Zhu L, Xu X, Yu Q, Hao W. Study on the flow characteristics of the pulsating intermittent liquid-solid fluidized bed with sinusoidal liquid velocity. POWDER TECHNOL 2021. [DOI: 10.1016/j.powtec.2021.07.075] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Tong Q, Wang G, Chen M, Chen Y, Guo Y. Preparation and performance evaluation of novel magnetic porous carriers in fluidized bed bioreactor for wastewater treatment. Biodegradation 2021; 32:677-695. [PMID: 34514545 DOI: 10.1007/s10532-021-09960-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2021] [Accepted: 09/06/2021] [Indexed: 11/24/2022]
Abstract
Biofilm process is a promising wastewater treatment technology and biofilm carrier (biocarrier) is regarded as the core of this process. However, the traditional commercial biocarriers have their inherent drawbacks, therefore, the development of new-type biocarrier to enhance wastewater treatment efficiency is significantly important to biofilm-based reactors. In this study, based on radical suspension polymerization, a novel kind of magnetic porous carriers (PMCs) was prepared by modifying the porous polymer carriers (PPCs) with inorganic particles, and then applied in a fluidized bed bioreactor (FBBR) with a low packing ratio of 10 % (v/v) to synthetic wastewater treatment. The results showed that this novel biocarrier possesses paramagnetism with saturation magnetization of 1.01emu/g, low density (1.26 g/cm3), excellent hydrophilicity (surface water contact angle approaching zero) and rough surface. Besides, compared with the PPCs, the developed PMCs have larger pores (up to 50 μm or more), in which the larger-sized microbes are able to colonize. Moreover, as compared to the PPCs-based FBBR, the PMCs-based reactor achieved shorter time (7 days) for biofilm formaiton and significantly enhanced NH3-N removal efficiency ( nearly 20 % increase at the level of influent NH3-N concentration about 100 mg/L). High-throughput sequencing (HTS) results indicated that this new biocarrier could promote biodiversity and improve the abundance of Nitrosomonadales (the functional bacteria for ammonia removal in the bio-system), thus enhancing the ammonification process. Therefore, the developed PMCs could be preferable biocarriers for biofilm formation and provide an alternative to the traditional suspended biocarrier, demonstrating a promising potential, even at a lower filling ratio, to enhance the pollutants removal performance.
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Affiliation(s)
- Qibang Tong
- School of Chemical Engineering, Sichuan University, Chengdu, 610065, China
| | - Guixin Wang
- School of Chemical Engineering, Sichuan University, Chengdu, 610065, China
| | - Maolian Chen
- School of Chemical Engineering, Sichuan University, Chengdu, 610065, China
| | - Yaping Chen
- School of Chemical Engineering, Sichuan University, Chengdu, 610065, China
| | - Yong Guo
- School of Chemical Engineering, Sichuan University, Chengdu, 610065, China.
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Yu L, Chen Z, Hu D, Ge H, Liu L, Liu Z, Liu H, Cui Y, Zhang W, Zou X, Zhang Y, Zhu Q. A novel low temperature aerobic technology with electrochemistry for treating pesticide wastewater: Compliance rate, mathematical models, economic and environmental benefit analysis. BIORESOURCE TECHNOLOGY 2021; 336:125285. [PMID: 34051570 DOI: 10.1016/j.biortech.2021.125285] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Revised: 05/07/2021] [Accepted: 05/09/2021] [Indexed: 06/12/2023]
Abstract
In this study, a novel combination system of the tapered variable diameter biological fluidized bed (TVDBFB) with electrochemistry (EC) has been developed and its performances are investigated at different seasons. The results showed that the COD removal efficiency of TVDBFB increased from 61% to 67% and compliance rate increased from 84% to 88% when the carrier packing rate increased from 15% to 30% and temperature was 12 ℃. However, COD removal efficiency and compliance rate increased to 87% and 100% when EC was a post treatment unit. The mathematical models could fit well with the attached biomass, which can be applied to reflect and predict the biomass per unit carrier under different conditions, and the EC removal of COD follow the first-order reaction kinetic model. The economic and environmental benefit analysis indicated that TVDBFB and EC were feasible for treating pesticide wastewater.
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Affiliation(s)
- Liqiang Yu
- Key Laboratory of Biotechnology and Bioresources Utilization, Ministry of Education, Dalian Minzu University, 18 Liaohe Road West, Dalian Economic and Technological Development Zone, Dalian 116600, PR China; College of Environment and Resources, Dalian Minzu University, 18 Liaohe West Road, Dalian 116600, PR China
| | - Zhaobo Chen
- Key Laboratory of Biotechnology and Bioresources Utilization, Ministry of Education, Dalian Minzu University, 18 Liaohe Road West, Dalian Economic and Technological Development Zone, Dalian 116600, PR China; College of Environment and Resources, Dalian Minzu University, 18 Liaohe West Road, Dalian 116600, PR China
| | - Dongxue Hu
- Key Laboratory of Biotechnology and Bioresources Utilization, Ministry of Education, Dalian Minzu University, 18 Liaohe Road West, Dalian Economic and Technological Development Zone, Dalian 116600, PR China; College of Environment and Resources, Dalian Minzu University, 18 Liaohe West Road, Dalian 116600, PR China.
| | - Hui Ge
- Key Laboratory of Biotechnology and Bioresources Utilization, Ministry of Education, Dalian Minzu University, 18 Liaohe Road West, Dalian Economic and Technological Development Zone, Dalian 116600, PR China; College of Environment and Resources, Dalian Minzu University, 18 Liaohe West Road, Dalian 116600, PR China
| | - Lixue Liu
- Key Laboratory of Biotechnology and Bioresources Utilization, Ministry of Education, Dalian Minzu University, 18 Liaohe Road West, Dalian Economic and Technological Development Zone, Dalian 116600, PR China; College of Environment and Resources, Dalian Minzu University, 18 Liaohe West Road, Dalian 116600, PR China
| | - Zhiguo Liu
- Shandong Provincial Academy of Architectural Science Co., Ltd, 29 Wuyingshan Street, Jinan 250000, PR China
| | - Hongxia Liu
- Shandong Provincial Academy of Architectural Science Co., Ltd, 29 Wuyingshan Street, Jinan 250000, PR China
| | - Yubo Cui
- Key Laboratory of Biotechnology and Bioresources Utilization, Ministry of Education, Dalian Minzu University, 18 Liaohe Road West, Dalian Economic and Technological Development Zone, Dalian 116600, PR China; College of Environment and Resources, Dalian Minzu University, 18 Liaohe West Road, Dalian 116600, PR China
| | - Wanjun Zhang
- Key Laboratory of Biotechnology and Bioresources Utilization, Ministry of Education, Dalian Minzu University, 18 Liaohe Road West, Dalian Economic and Technological Development Zone, Dalian 116600, PR China; College of Environment and Resources, Dalian Minzu University, 18 Liaohe West Road, Dalian 116600, PR China
| | - Xuejun Zou
- Key Laboratory of Biotechnology and Bioresources Utilization, Ministry of Education, Dalian Minzu University, 18 Liaohe Road West, Dalian Economic and Technological Development Zone, Dalian 116600, PR China; College of Environment and Resources, Dalian Minzu University, 18 Liaohe West Road, Dalian 116600, PR China
| | - Ying Zhang
- School of Resources and Environmental Science, Northeast Agricultural University, 59 Mucai Street, HarBin 150030, PR China
| | - Qiankun Zhu
- Technology Center of Dalian Customs, 58 Lianshan Road, Shahekou Zone, Dalian 116600, PR China
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Ge H, Yu L, Chen Z, Liu Z, Liu H, Hu D, Wang H, Cui Y, Zhang W, Zou X, Zhang Y. Novel tapered variable diameter biological fluidized bed for treating pesticide wastewater with high nitrogen removal efficiency and a small footprint. BIORESOURCE TECHNOLOGY 2021; 330:124989. [PMID: 33765630 DOI: 10.1016/j.biortech.2021.124989] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2021] [Revised: 03/06/2021] [Accepted: 03/09/2021] [Indexed: 05/22/2023]
Abstract
In this study, the removal efficiency of nitrogen, specific nitrification rate (SNR), specific denitrification rate (SDNR) and compliance rate of the novel tapered variable diameter biological fluidized bed (TVDBFB) and anoxic/oxic (AO) process were compared at different temperatures. The results showed that the optimal TN, NH4+-N, and TKN removal efficiencies of the TVDBFB were 76%, 89% and 88%, respectively, and those of AO were 65%, 67% and 69%, respectively. The SNR and SDNR of the TVDBFB were significantly higher than those of AO. The TVDBFB had a smaller footprint than AO. The alkalinity/NH4+-N, BOD5/TN and temperature play important roles in the compliance rate. Increasing the carrier packing rate has emerged as a new strategy for enhancing the compliance rate. Mathematical models were developed and determined to be well-fitted with the experimental values, which can be employed to predict the SNR and SDNR of the TVDBFB.
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Affiliation(s)
- Hui Ge
- Key Laboratory of Biotechnology and Bioresources Utilization, Ministry of Education, Dalian Minzu University, 18 Liaohe Road West, Dalian Economic and Technological Development Zone, Dalian 116600, PR China; College of Environment and Resources, Dalian Minzu University, 18 Liaohe West Road, Dalian 116600, PR China
| | - Liqiang Yu
- Key Laboratory of Biotechnology and Bioresources Utilization, Ministry of Education, Dalian Minzu University, 18 Liaohe Road West, Dalian Economic and Technological Development Zone, Dalian 116600, PR China; College of Environment and Resources, Dalian Minzu University, 18 Liaohe West Road, Dalian 116600, PR China
| | - Zhaobo Chen
- Key Laboratory of Biotechnology and Bioresources Utilization, Ministry of Education, Dalian Minzu University, 18 Liaohe Road West, Dalian Economic and Technological Development Zone, Dalian 116600, PR China; College of Environment and Resources, Dalian Minzu University, 18 Liaohe West Road, Dalian 116600, PR China.
| | - Zhiguo Liu
- Shandong Provincial Academy of Architectural Science Co., Ltd, 29 Wuyingshan Street, Jinan 250000, PR China
| | - Hongxia Liu
- Shandong Provincial Academy of Architectural Science Co., Ltd, 29 Wuyingshan Street, Jinan 250000, PR China
| | - Dongxue Hu
- Key Laboratory of Biotechnology and Bioresources Utilization, Ministry of Education, Dalian Minzu University, 18 Liaohe Road West, Dalian Economic and Technological Development Zone, Dalian 116600, PR China; College of Environment and Resources, Dalian Minzu University, 18 Liaohe West Road, Dalian 116600, PR China
| | - Hongcheng Wang
- School of Civil & Environmental Engineering, Harbin Institute of Technology (Shenzhen), Shenzhen 518055, PR China
| | - Yubo Cui
- Key Laboratory of Biotechnology and Bioresources Utilization, Ministry of Education, Dalian Minzu University, 18 Liaohe Road West, Dalian Economic and Technological Development Zone, Dalian 116600, PR China; College of Environment and Resources, Dalian Minzu University, 18 Liaohe West Road, Dalian 116600, PR China
| | - Wanjun Zhang
- Key Laboratory of Biotechnology and Bioresources Utilization, Ministry of Education, Dalian Minzu University, 18 Liaohe Road West, Dalian Economic and Technological Development Zone, Dalian 116600, PR China; College of Environment and Resources, Dalian Minzu University, 18 Liaohe West Road, Dalian 116600, PR China
| | - Xuejun Zou
- Key Laboratory of Biotechnology and Bioresources Utilization, Ministry of Education, Dalian Minzu University, 18 Liaohe Road West, Dalian Economic and Technological Development Zone, Dalian 116600, PR China; College of Environment and Resources, Dalian Minzu University, 18 Liaohe West Road, Dalian 116600, PR China
| | - Ying Zhang
- School of Resources and Environmental Science, Northeast Agricultural University, 59 Mucai Street, HarBin 150030, PR China
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He X, Li H, Zhu J. A value-added step towards promoting the serviceability of fluidized bed bioreactor in treating wastewater with low carbon to nitrogen ratio. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 750:141665. [PMID: 33182169 DOI: 10.1016/j.scitotenv.2020.141665] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Revised: 08/10/2020] [Accepted: 08/10/2020] [Indexed: 06/11/2023]
Abstract
Reusing microplastics and zeolite waste as free ammonia (FA)-mitigating carrier particle was proven a value-added step towards promoting the serviceability of fluidized bed bioreactor (FBBR) in treating wastewater with a low carbon to nitrogen ratio (i.e. C/N <3.0) in this study. Ammonia (NH4+) adsorption property capacitates zeolite as an FA mitigator. The microplastics and reused zeolite were processed into reused-zeolite/microplastic composite particle (RZ), whose merit of FA mitigation was fully developed via an optimally thermal modification to process modified-zeolite/microplastic particle (MZ). The 171-day biological nutrient removal (BNR) performance in a single integrated fluidized bed bioreactor (SIFBBR) shows that the bioreactor with MZ particle (SIFBBR-MZ) achieved nitrogen removal efficiency 10.0% higher than the bioreactor with RZ particle (SIFBBR-RZ) over the enhanced short-cut nitrification and denitrification. Analysis of microbial community structure unveils that the long-term lower FA inhibition favored more significant ammonia-oxidizing bacteria (AOB) enrichment and acclimated specific MZ biofilm predominant by nitrite (NO2-) denitrifier, contributing to the outperformance in nitrogen removal. Apart from fluidization energy conservation, the techno-economic analysis confirms that using MZ as an FA-mitigating carrier could be of great benefit for FBBR system: realizing waste utilization, reducing carbon addition and alleviating sludge treatment.
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Affiliation(s)
- Xiaoqin He
- Key Laboratory of Renewable Energy, Guangdong Key Laboratory of New and Renewable Energy Research and Development Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Haibin Li
- Key Laboratory of Renewable Energy, Guangdong Key Laboratory of New and Renewable Energy Research and Development Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, China.
| | - Jesse Zhu
- Department of Chemical and Biochemical Engineering, Western University, London N6A 5B9, Canada.
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