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Izadi P, Izadi P, Eldyasti A. Enhancement of simultaneous nitrogen and phosphorus removal using intermittent aeration mechanism. J Environ Sci (China) 2021; 109:1-14. [PMID: 34607658 DOI: 10.1016/j.jes.2021.02.026] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2020] [Revised: 02/23/2021] [Accepted: 02/23/2021] [Indexed: 06/13/2023]
Abstract
Biological nutrient removal grows into complicated scenario due to the microbial consortium shift and kinetic competition between phosphorus (P)-accumulating and nitrogen (N)-removing microorganisms. In this study, three sequential batch reactors with constant operational conditions except aeration patterns at 6 h cycle periods were tested. Intermittent aeration was applied to develop a robust nutrient removal system aimed to achieve high energy saving and removal efficiency. The results showed higher correspondence of P-uptake, polymeric substance synthesis and glycogen degradation in intermittent-aeration with longer interval periods compared to continuous-aeration. Increasing the intermittent-aeration duration from 25 to 50 min, resulted in higher process performance where the system exhibited approximately 30% higher nutrient removal. This study indicated that nutrient removal strongly depends on reaction phase configuration representing the importance of aeration pattern. The microbial community examined the variation in abundance of bacterial groups in suspended sludge, where the 50 min intermittent aeration, favored the growth of P-accumulating organisms and nitrogen removal microbial groups, indicating the complications related to nutrient removal systems. Successful intermittently aerated process with high capability of simple implementation to conventional systems by elemental retrofitting, is applicable for upgrading wastewater treatment plants. With aeration as a major operational cost, this process is a promising approach to potentially remove nutrients in high competence, in distinction to optimizing cost-efficacy of the system.
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Affiliation(s)
- Parnian Izadi
- Civil engineering, York university, 4700 Keele St, Toronto, ON, Canada
| | - Parin Izadi
- Civil engineering, York university, 4700 Keele St, Toronto, ON, Canada
| | - Ahmed Eldyasti
- Civil engineering, York university, 4700 Keele St, Toronto, ON, Canada.
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2
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Sui Q, Wang Y, Wang H, Yue W, Chen Y, Yu D, Chen M, Wei Y. Roles of hydroxylamine and hydrazine in the in-situ recovery of one-stage partial nitritation-anammox process: Characteristics and mechanisms. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 707:135648. [PMID: 31780172 DOI: 10.1016/j.scitotenv.2019.135648] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Revised: 10/31/2019] [Accepted: 11/18/2019] [Indexed: 06/10/2023]
Abstract
Nitrate built-up is a serious operational difficulty in one-stage partial nitritation anammox (PN/A) process. To investigate an effective method for in-situ restoration, hydroxylamine (NH2OH) and hydrazine (N2H4) of 2 mgN/L were dosed in PN/A process with nitrate built-up in a comparative study. NH2OH treatment showed better performances on TN removal and nitrate reduction than N2H4 and blank control. Through 104 days' addition of NH2OH, MRNN (mole ratio of NO3--N production to NH4+-N removal) was decreased from 70% to 19.91%; TN removal was increased from 0.01 to 0.18 kgN/(m3 d). After stopping the chemical addition, nitrate rebounded for N2H4 treatment, but the restoration effect was stable and persistent for NH2OH. NH2OH addition resulted in a low reductive potential (-250 mV) and exerted strong inhibitions on nitrite oxidizing bacteria activities. Additionally, rapid enhancement of ammonia oxidizing bacteria activities, functional gene (hao) and Nitrosomonas gave rise to the restoration of PN/A with NH2OH addition.
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Affiliation(s)
- Qianwen Sui
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; Department of Water Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Yuanyue Wang
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; Department of Water Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Hongyan Wang
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; Department of Water Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Wenhui Yue
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; Department of Water Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yanlin Chen
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; Department of Water Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Dawei Yu
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; Department of Water Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Meixue Chen
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; Department of Water Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Yuansong Wei
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; Department of Water Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China; Institute of Energy, Jiangxi Academy of Sciences, Nanchang 330096, China.
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Barak J, Dotro G, Jefferson B. The role of concentrations gradients on phosphorus and iron dynamics from chemically-dosed horizontal flow wetlands for tertiary sewage treatment. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2019; 79:2126-2134. [PMID: 31318350 DOI: 10.2166/wst.2019.215] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
This study examined the dynamics of iron (Fe) and phosphorus (P) transformations from the surface sludge accumulated in tertiary horizontal flow (HF) treatment wetlands (TW) chemically dosed for P removal. Site surveys showed P was stored in HF TW with and without artificial aeration on average, with instances of P release in the non-aerated site. Controlled experiments revealed storing TW surface sludge for over 24 hours resulted in limited oxygen and nitrate concentrations, resulting in both P and Fe release. The rate of P release increased with increasing water-sludge P concentration gradients, and the reaction could take as little as 10 minutes. Convection had no impact on P transformation rates. The findings suggest mitigation strategies could include the manipulation of the biogeochemical environment by managing oxygen and nitrate concentrations within the wetlands. A better understanding of links between Fe, P, and nitrate is needed to test proactive mitigation strategies for small wastewater treatment plants.
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Affiliation(s)
- Jan Barak
- Cranfield University, College Road, Cranfield, Bedfordshire, MK43 0AL, UK E-mail:
| | - Gabriela Dotro
- Cranfield University, College Road, Cranfield, Bedfordshire, MK43 0AL, UK E-mail:
| | - Bruce Jefferson
- Cranfield University, College Road, Cranfield, Bedfordshire, MK43 0AL, UK E-mail:
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Soil Media CO2 and N2O Fluxes Dynamics from Sand-Based Roadside Bioretention Systems. WATER 2018. [DOI: 10.3390/w10020185] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Singh NK, Bhatia A, Kazmi AA. Effect of intermittent aeration strategies on treatment performance and microbial community of an IFAS reactor treating municipal waste water. ENVIRONMENTAL TECHNOLOGY 2017; 38:2866-2876. [PMID: 28076690 DOI: 10.1080/09593330.2017.1281349] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2016] [Accepted: 01/08/2017] [Indexed: 06/06/2023]
Abstract
This study investigated the effect of various intermittent aeration (IA) cycles on organics and nutrient removal, and microbial communities in an integrated fixed-film activated sludge (IFAS) reactor treating municipal waste water. Average effluent biological oxygen demand (BOD), chemical oxygen demand (COD), total suspended solids, total nitrogen (TN) and total phosphorus (TP) values were noted as 20, 50, 30, 12 and 1.5 mgL-1, respectively, in continuous aeration mode. A total of four operational conditions (run 1, continuous aeration; run 2, 150/30 min aeration on/off time; run 3, 120/60 min aeration on/off time and run 4, 90/60 min aeration on/off time) were investigated in IFAS reactor assessment. Among the all examined IA cycles, IA phase 2 gave the maximum COD and BOD removals with values recorded as 97% and 93.8%, respectively. With respect to nutrient removal (TN and TP), IA phase 1 was found to be optimum. Pathogen removal efficiency of present system was recorded as 90-95% during the three phases. With regard to settling characteristics, pilot showed poor settling during IA schedules, which was also evidenced by high sludge volume index values. Overall, IA could be used as a feasible way to improve the overall performance of IFAS system.
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Affiliation(s)
- Nitin Kumar Singh
- a Department of Civil Engineering , Indian Institute of Technology , Roorkee , India
| | - Akansha Bhatia
- a Department of Civil Engineering , Indian Institute of Technology , Roorkee , India
| | - Absar Ahmad Kazmi
- a Department of Civil Engineering , Indian Institute of Technology , Roorkee , India
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Study of Carbonaceous and Nitrogenous Pollutant Removal Efficiencies in a Hybrid Membrane Bioreactor. J CHEM-NY 2017. [DOI: 10.1155/2017/4080847] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
A hybrid membrane bioreactor (HMBR) comprises activated sludge (free biomass), a biofilm (supported biomass), and a membrane separation. A laboratory pilot-scale HMBR was operated for seven months with high organic loads of both carbonic and nitrogen pollutants. Several experiments were conducted to investigate the influence of the height of the packing bed (27 cm, 50 cm, and 0 cm) and the effect of the concentration of dissolved oxygen (DO) on the organic removal rate, total nitrogen removal rate (TN), and ammonium removal. The organic removal rate was always >95% and mostly >98%. The NH4+-N and TN removal rates were directly related to DO. NH4+-N removal rate reached 100% and was mostly >99% with a concentration of DO > 0.1 mg/L, whereas the NO3--N removal rate was differentially affected depending on the level of DO. The removal rate increased when the concentration of DO was optimal for simultaneous nitrification and denitrification, which was between 0.1 and 0.5 mg/l, and the TN removal rate was consequently high. The removal rate decreased when DO was high and denitrification was consequently low thereby reducing the TN removal rate. This implies that high levels of DO (>1 mg/L) limit the denitrification process and low levels of DO (<0.1 mg/L) limit the nitrification process and hence total nitrogen removal in the bioreactor.
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Xin X, He J, Wang Y, Feng J, Qiu W. Role of aeration intensity on performance and microbial community profiles in a sequencing batch reaction kettle (SBRK) for wastewater nutrients rapid removal. BIORESOURCE TECHNOLOGY 2016; 201:140-147. [PMID: 26642219 DOI: 10.1016/j.biortech.2015.11.053] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2015] [Revised: 11/17/2015] [Accepted: 11/18/2015] [Indexed: 06/05/2023]
Abstract
A lab-scale SBRK was operated to investigate the effects of aeration intensity on the system performance and microbial community dynamics within it. Results showed that the sewage nutrients was removed rapidly (just about 3-6h) with the aeration intensity increasing from 0 to 0.6MPa. Average effluent parameters were: COD below 50mg/L, NH4(+)-N less than 1mg/L, 1.5-4.5mg/L for nitrate and TP below 0.5mg/L. The highest community similarity and diversity emerged simultaneously with the aeration pressure rising from 0.2 to 0.4MPa, which was regarded as the optimal aeration intensity range. Microbial community shifted obviously and the function species of Comamonadaceae, Dechloromonas, Flavobacterium and Nitrospira dominated in the corresponding communities. RDA indicated that aeration intensity was the main factor for regulating system communities to optimize the system performance. It inferred that high aeration pressure played a key role on sewage nutrients rapid removal.
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Affiliation(s)
- Xiaodong Xin
- School of Municipal and Environmental Engineering, Harbin Institute of Technology (HIT), Harbin 150090, China
| | - Junguo He
- School of Municipal and Environmental Engineering, Harbin Institute of Technology (HIT), Harbin 150090, China
| | - Yuefei Wang
- School of Municipal and Environmental Engineering, Harbin Institute of Technology (HIT), Harbin 150090, China
| | - Jinghan Feng
- School of Municipal and Environmental Engineering, Harbin Institute of Technology (HIT), Harbin 150090, China
| | - Wei Qiu
- School of Municipal and Environmental Engineering, Harbin Institute of Technology (HIT), Harbin 150090, China.
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Eusebi AL, Santinelli M, Battistoni P. Production of nitrogen oxide gases from an oxic/anoxic process via nitrite: influence of liquid parameters and impact on mass balance. ENVIRONMENTAL TECHNOLOGY 2015; 36:1213-1222. [PMID: 25367331 DOI: 10.1080/09593330.2014.983552] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The produced nitrogen oxides from the biological treatment of swine and dairy anaerobic supernatant are evaluated. The quantification of the emissions has been conducted in a continuous way and coupled with batch tests to determine the mechanisms of formation. Using a continuous monitoring system, N2O and NO forms are present in higher quantities than NO2. The elevated emissions are linked with the increment of the influent nitrogen load both in the daily variations and in the long period. The NH4-N and NO2-N accumulations are recognized as the main parameters which determine the great nitrogen oxide emissions even at dissolved oxygen concentration of around 2 mgL(-1). The nitrogen oxides' impacts are between 0.0034 and 0.0044N% for the N2O and between 0.0020 and 0.0026N% for NO. A strict dependence between the N2O and the oxidation reduction potential is found.
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Affiliation(s)
- Anna Laura Eusebi
- a Dipartimento SIMAU, Facoltà di Ingegneria , Università Politecnica delle Marche , Via Brecce Bianche, 12, Ancona 60100 , Italy
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Hanada A, Kurogi T, Giang NM, Yamada T, Kamimoto Y, Kiso Y, Hiraishi A. Bacteria of the candidate phylum TM7 are prevalent in acidophilic nitrifying sequencing-batch reactors. Microbes Environ 2014; 29:353-62. [PMID: 25241805 PMCID: PMC4262358 DOI: 10.1264/jsme2.me14052] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Laboratory-scale acidophilic nitrifying sequencing-batch reactors (ANSBRs) were constructed by seeding with sewage-activated sludge and cultivating with ammonium-containing acidic mineral medium (pH 4.0) with or without a trace amount of yeast extract. In every batch cycle, the pH varied between 2.7 and 4.0, and ammonium was completely converted to nitrate. Attempts to detect nitrifying functional genes in the fully acclimated ANSBRs by PCR with previously designed primers mostly gave negative results. 16S rRNA gene-targeted PCR and a subsequent denaturating gradient gel electrophoresis analysis revealed that a marked change occurred in the bacterial community during the overall period of operation, in which members of the candidate phylum TM7 and the class Gammaproteobacteria became predominant at the fully acclimated stage. This result was fully supported by a 16S rRNA gene clone library analysis, as the major phylogenetic groups of clones detected (>5% of the total) were TM7 (33%), Gammaproteobacteria (37%), Actinobacteria (10%), and Alphaproteobacteria (8%). Fluorescence in situ hybridization with specific probes also demonstrated the prevalence of TM7 bacteria and Gammaproteobacteria. These results suggest that previously unknown nitrifying microorganisms may play a major role in ANSBRs; however, the ecophysiological significance of the TM7 bacteria predominating in this process remains unclear.
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Affiliation(s)
- Akiko Hanada
- Department of Environmental and Life Sciences, Toyohashi University of Technology
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Wang W, Chen S, Bao K, Gao J, Zhang R, Zhang Z, Sugiura N. Enhanced removal of contaminant using the biological film, anoxic-anaerobic-aerobic and electro-coagulation process applied to high-load sewage treatment. ENVIRONMENTAL TECHNOLOGY 2014; 35:833-840. [PMID: 24645465 DOI: 10.1080/09593330.2013.852628] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
In order to explore a new treatment process applying to decentralized domestic sewage treatment, and enhance removal of total nitrogen (TN), total phosphorus (TP) and chemical oxygen demand (COD), a novel system integrating anoxic-anaerobic-aerobic (reversed A2O) and electro-coagulation (EC) process was studied, and complex biological media (CMB) was used as suspended carrier for biofilm development. In this work, TN, TP and COD removal performance were investigated with consideration of three major factors, hydraulic retention time (HRT), organic loading rate (OLR) and sludge recycle ratio (SRR). Results showed that (1) The optimum HRT was between 8 and 12 h. The removal efficiencies of TN, TP and COD were about 68%, 95% and 95%, respectively. (2) With the increase of OLR, the removal efficiency of TN increased slowly. But it increased first and then declined for COD and TP removal. Their maximum were attained when OLR was 1.8 g(COD)/(L d), and they were 96% and 93%, respectively. (3) The optimum SRR was 75%. The COD, TN and TP removal efficiencies were about 95%, 72% and 98%, respectively. In this system, the maximum TN and COD removal were achieved in anoxic tank, but it was achieved in aerobic tank for TP removal. The EC bed enhanced the effluent quality, especially the efficiency in advanced P removal. From these results, it was concluded that the new process could be a reliable option for providing excellent effluent quality.
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Cho K, Chung CM, Kim YJ, Hoffmann MR, Chung TH. Electroflotation clarifier to enhance nitrogen removal in a two-stage alternating aeration bioreactor. ENVIRONMENTAL TECHNOLOGY 2013; 34:2765-2772. [PMID: 24527640 DOI: 10.1080/09593330.2013.788072] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Stringent water treatment criteria and rapidly growing pollutant loads provoke the demand for retrofitting wastewater treatment plants towards a higher capacity. In this study, we assess a two stage alternating aeration (AA) bioreactor equipped with electroflotation (EF) clarifier, for nitrogen removal within a short hydraulic retention time (HRT). The EF under steady solids loading required a minimum unit height and gas: solids ratio of 0.006 for efficient clarification. The separated sludge blanket was further thickened with retaining stability when the cyclic solids loading was smaller than 1.0 kg m(-2). In the continuous operation of the bioreactor, the returned activated sludge concentration increased to more than 18,000 mg L(-1), while the effluent suspended solids concentration was lowered below 5 mg L(-1). Under influent chemical oxygen demand (COD)/total inorganic nitrogen (TIN) concentration of 300/30 mg L(-1), the TIN removal efficiency was near 70% with cycle time ratios of 0.17 and 0.27. Under higher influent COD concentration of 500mg L(-1), TIN removal efficiency was found to be 73.4% at a carbon:nitrogen (C:N) ratio of 10 and even higher (80.4%) at a C:N ratio of 16.6. The increased mixed liquor suspended solids concentrations (> 6000 mg L(-1)) under the high COD loading were efficiently maintained by using the EF clarifier. The results of this study demonstrate that an EF clarifier with a HRT of less than 1 h can support reliable nitrogen removal in the AA process that has a HRT of 6 h, even under increasing influent loadings.
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Affiliation(s)
- Kangwoo Cho
- Linde-Robinson Laboratories, California Institute of Technology, Pasadena, CA, USA
| | - Chong Min Chung
- Department of Urban Engineering, The University of Tokyo, Bunkyo, Tokyo, Japan
| | - Yun Jung Kim
- R&D Center, POSCO E&C, Younsugu, Incheon, Republic of Korea
| | - Michael R Hoffmann
- Linde-Robinson Laboratories, California Institute of Technology, Pasadena, CA, USA
| | - Tai Hak Chung
- Department of Civil and Environmental Engineering, Seoul National University, Gwanak-gu, Seoul, Republic of Korea
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Hocaoglu SM, Atasoy E, Baban A, Insel G, Orhon D. Nitrogen removal performance of intermittently aerated membrane bioreactor treating black water. ENVIRONMENTAL TECHNOLOGY 2013; 34:2717-2725. [PMID: 24527634 DOI: 10.1080/09593330.2013.786139] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The study investigated the effect of intermittent aeration on the nitrogen removal performance of a membrane bioreactor (MBR) treating black water. A pilot-scale MBR with an effective volume of 630 L operating as a sequencing batch reactor (SBR) with intermittent aeration was used in the experiments. Substrate feeding was limited to the initial non-aerated phase. The MBR unit was sustained at a steady state at a sludge age of 60 d with a biomass concentration of around 10,000 mg/L for 3 months. The treated black water could be characterized with an average COD of 950 mg/L and total nitrogen of 172 mg/L, corresponding to a low COD/N ratio of 5.5. The selected MBR scheme was quite effective, reducing COD down to 26 mg/L, providing effective nitrification and yielding a total oxidized nitrogen concentration under 10 mg N/L. The nitrogen removal performance was substantially better than the level predicted by process stoichiometry, due to multiple anoxic configuration inducing additional nitrogen removal. Dissolved oxygen profiles associated with the cyclic operation of the system suggested that the incremental nitrogen removal could be attributed to simultaneous nitrification-denitrification, a commonly observed mechanism in MBR systems sustained at high biomass concentrations.
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Affiliation(s)
- S Murat Hocaoglu
- TUBITAK Marmara Research Centre, Environment Institute, Gebze, Turkey.
| | - E Atasoy
- TUBITAK Marmara Research Centre, Environment Institute, Gebze, Turkey
| | - A Baban
- TUBITAK Marmara Research Centre, Environment Institute, Gebze, Turkey
| | - G Insel
- Environmental Engineering Department, Istanbul Technical University, Istanbul, Turkey
| | - D Orhon
- Environmental Engineering Department, Istanbul Technical University, Istanbul, Turkey
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Aboobakar A, Cartmell E, Stephenson T, Jones M, Vale P, Dotro G. Nitrous oxide emissions and dissolved oxygen profiling in a full-scale nitrifying activated sludge treatment plant. WATER RESEARCH 2013; 47:524-534. [PMID: 23159006 DOI: 10.1016/j.watres.2012.10.004] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2012] [Revised: 10/03/2012] [Accepted: 10/04/2012] [Indexed: 06/01/2023]
Abstract
This paper reports findings from online, continuous monitoring of dissolved and gaseous nitrous oxide (N₂O), combined with dissolved oxygen (DO) and ammonia loading, in a full-scale nitrifying activated sludge plant. The study was conducted over eight weeks, at a 210,000 population equivalent sewage treatment works in the UK. Results showed diurnal variability in the gaseous and dissolved N₂O emissions, with hourly averages ranging from 0 to 0.00009 kgN₂O-N/h for dissolved and 0.00077-0.0027 kgN₂O-N/h for gaseous nitrous oxide emissions respectively, per ammonia loading, depending on the time of day. Similarly, the spatial variability was high, with the highest emissions recorded immediately after the anoxic zone and in the final pass of the aeration lane, where ammonia concentrations were typically below 0.5 mg/L. Emissions were shown to be negatively correlated to dissolved oxygen, which fluctuated between 0.5 and 2.5 mgO₂/L, at the control set point of 1.5 mgO₂/L. The resulting dynamic DO conditions are known to favour N₂O production, both by autotrophic and heterotrophic processes in mixed cultures. Average mass emissions from the lane were greater in the gaseous (0.036% of the influent total nitrogen) than in the dissolved (0.01% of the influent total nitrogen) phase, and followed the same diurnal and spatial patterns. Nitrous oxide emissions corresponded to over 34,000 carbon dioxide equivalents/year, adding 13% to the carbon footprint associated with the energy requirements of the monitored lane. A clearer understanding of emissions obtained from real-time data can help towards finding the right balance between improving operational efficiency and saving energy, without increasing N₂O emissions.
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Affiliation(s)
- Amina Aboobakar
- Cranfield Water Science Institute, School of Applied Sciences, Cranfield University, College Road, Cranfield, Bedfordshire MK43 0AL, United Kingdom
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Isolation, identification and removal of filamentous organism from SND based SBR degrading nitrophenols. Biodegradation 2011; 23:455-63. [DOI: 10.1007/s10532-011-9524-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2011] [Accepted: 11/16/2011] [Indexed: 10/15/2022]
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