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Ma Y, Rui D, Dong H, Zhang X, Ye L. Large-scale comparative analysis reveals different bacterial community structures in full- and lab-scale wastewater treatment bioreactors. WATER RESEARCH 2023; 242:120222. [PMID: 37331228 DOI: 10.1016/j.watres.2023.120222] [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: 03/13/2023] [Revised: 05/16/2023] [Accepted: 06/12/2023] [Indexed: 06/20/2023]
Abstract
The activated sludge process is widely used for biological wastewater treatment due to its low cost and high efficiency. Although numerous lab-scale bioreactor experiments have been conducted to investigate the microorganism performance and mechanisms in activated sludge, understanding the bacterial community differences between full- and lab-scale bioreactors has remained elusive. In this study, we investigated the bacterial communities in 966 activated sludge samples obtained from various bioreactors, including both full- and lab-scale ones, from 95 previous studies. Our findings reveal significant differences in the bacterial communities between full- and lab-scale bioreactors, with thousands of bacterial genera exclusive to each scale. We also identified 12 genera that are frequently abundant in full-scale bioreactors but rarely observed in lab-scale reactors. By using a machine-learning method, organic matter and temperature were determined as the primary factors affecting microbial communities in full- and lab-scale bioreactors. Additionally, transient bacterial species from other environments may also contribute to the observed bacterial community differences. Furthermore, the bacterial community differences between full- and lab-scale bioreactors were verified by comparing the results of lab-scale bioreactor experiments to full-scale bioreactor sampling. Overall, this study sheds light on the bacteria overlooked in lab-scale studies and deepens our understanding of the differences in bacterial communities between full- and lab-scale bioreactors.
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Affiliation(s)
- Yanyan Ma
- State Key Laboratory of Pollution Control and Resource Reuse, School of Environment, Nanjing University, Nanjing, Jiangsu, China
| | - Dongni Rui
- State Key Laboratory of Pollution Control and Resource Reuse, School of Environment, Nanjing University, Nanjing, Jiangsu, China
| | - Haonan Dong
- State Key Laboratory of Pollution Control and Resource Reuse, School of Environment, Nanjing University, Nanjing, Jiangsu, China
| | - Xuxiang Zhang
- State Key Laboratory of Pollution Control and Resource Reuse, School of Environment, Nanjing University, Nanjing, Jiangsu, China
| | - Lin Ye
- State Key Laboratory of Pollution Control and Resource Reuse, School of Environment, Nanjing University, Nanjing, Jiangsu, China.
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2
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Eryildiz B, Yavuzturk Gul B, Koyuncu I. A sustainable approach for the removal methods and analytical determination methods of antiviral drugs from water/wastewater: A review. JOURNAL OF WATER PROCESS ENGINEERING 2022; 49:103036. [PMID: 35966450 PMCID: PMC9359512 DOI: 10.1016/j.jwpe.2022.103036] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2022] [Revised: 06/26/2022] [Accepted: 07/28/2022] [Indexed: 05/05/2023]
Abstract
In the last years, antiviral drugs especially used for the treatment of COVID-19 have been considered emerging contaminants because of their continuous occurrence and persistence in water/wastewater even at low concentrations. Furthermore, as compared to antiviral drugs, their metabolites and transformation products of these pharmaceuticals are more persistent in the environment. They have been found in environmental matrices all over the world, demonstrating that conventional treatment technologies are unsuccessful for removing them from water/wastewater. Several approaches for degrading/removing antiviral drugs have been studied to avoid this contamination. In this study, the present level of knowledge on the input sources, occurrence, determination methods and, especially, the degradation and removal methods of antiviral drugs are discussed in water/wastewater. Different removal methods, such as conventional treatment methods (i.e. activated sludge), advanced oxidation processes (AOPs), adsorption, membrane processes, and combined processes, were evaluated. In addition, the antiviral drugs and these metabolites, as well as the transformation products created as a result of treatment, were examined. Future perspectives for removing antiviral drugs, their metabolites, and transformation products were also considered.
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Affiliation(s)
- Bahriye Eryildiz
- Istanbul Technical University, Environmental Engineering Department, Maslak 34469, Istanbul, Turkey
- National Research Center on Membrane Technologies, Istanbul Technical University, Maslak 34469, Istanbul, Turkey
| | - Bahar Yavuzturk Gul
- National Research Center on Membrane Technologies, Istanbul Technical University, Maslak 34469, Istanbul, Turkey
- Department of Molecular Biology and Genetics, Istanbul Technical University, Maslak 34469, Istanbul, Turkey
| | - Ismail Koyuncu
- Istanbul Technical University, Environmental Engineering Department, Maslak 34469, Istanbul, Turkey
- National Research Center on Membrane Technologies, Istanbul Technical University, Maslak 34469, Istanbul, Turkey
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Dominic D, Baidurah S. Recent Developments in Biological Processing Technology for Palm Oil Mill Effluent Treatment-A Review. BIOLOGY 2022; 11:biology11040525. [PMID: 35453724 PMCID: PMC9031994 DOI: 10.3390/biology11040525] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Revised: 02/22/2022] [Accepted: 02/25/2022] [Indexed: 11/16/2022]
Abstract
Simple Summary Palm oil mill effluent (POME) requires treatment prior to discharge to the environment. Biological processing technology is highly preferable due to its advantages of environmentally friendliness, cost effectiveness, and practicality. These methods utilized various designs and modifications of bioreactors fostering effective fermentation technology in the presence of fungi, bacteria, microalgae, and a consortium of microorganisms. This review highlights the recent biological processing technology for POME treatment as a resource utilization. Abstract POME is the most voluminous waste generated from palm oil milling activities. The discharge of POME into the environment without any treatment processing could inflict an undesirable hazard to humans and the environment due to its high amount of toxins, organic, and inorganic materials. The treatment of POME prior to discharge into the environment is utmost required to protect the liability for human health and the environment. Biological treatments are preferable due to eco-friendly attributes that are technically and economically feasible. The goal of this review article is to highlight the current state of development in the biological processing technologies for POME treatment. These biological processing technologies are conducted in the presence of fungi, bacteria, microalgae, and a consortium of microorganisms. Numerous microbes are listed to identify the most efficient strain by monitoring the BOD, COD, working volume of the reactor, and treatment time. The most effective processing technology for POME treatment uses an upflow anaerobic sludge blanket reactor with the COD value of 99%, hydraulic retention time of 7.2 days, and a working volume of 4.7 litres. Biological processing technologies are mooted as an efficient and sustainable management practice of POME waste.
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Adeleye AS, Xue J, Zhao Y, Taylor AA, Zenobio JE, Sun Y, Han Z, Salawu OA, Zhu Y. Abundance, fate, and effects of pharmaceuticals and personal care products in aquatic environments. JOURNAL OF HAZARDOUS MATERIALS 2022; 424:127284. [PMID: 34655870 DOI: 10.1016/j.jhazmat.2021.127284] [Citation(s) in RCA: 90] [Impact Index Per Article: 45.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2020] [Revised: 09/06/2021] [Accepted: 09/16/2021] [Indexed: 06/13/2023]
Abstract
Pharmaceuticals and personal care products (PPCPs) are found in wastewater, and thus, the environment. In this study, current knowledge about the occurrence and fate of PPCPs in aquatic systems-including wastewater treatment plants (WWTPs) and natural waters around the world-is critically reviewed to inform the state of the science and highlight existing knowledge gaps. Excretion by humans is the primary route of PPCPs entry into municipal wastewater systems, but significant contributions also occur through emissions from hospitals, PPCPs manufacturers, and agriculture. Abundance of PPCPs in raw wastewater is influenced by several factors, including the population density and demography served by WWTPs, presence of hospitals and drugs manufacturers in the sewershed, disease burden of the population served, local regulations, and climatic conditions. Based on the data obtained from WWTPs, analgesics, antibiotics, and stimulants (e.g., caffeine) are the most abundant PPCPs in raw wastewater. In conventional WWTPs, most removal of PPCPs occurs during secondary treatment, and overall removal exceeds 90% for treatable PPCPs. Regardless, the total PPCP mass discharged with effluent by an average WWTP into receiving waters (7.35-20,160 g/day) is still considerable, because potential adverse effects of some PPCPs (such as ibuprofen) on aquatic organisms occur within measured concentrations found in surface waters.
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Affiliation(s)
- Adeyemi S Adeleye
- Department of Civil and Environmental Engineering, University of California, Irvine, CA 92697-2175, USA.
| | - Jie Xue
- Department of Civil and Environmental Engineering, University of California, Irvine, CA 92697-2175, USA
| | - Yixin Zhao
- Department of Civil and Environmental Engineering, University of California, Irvine, CA 92697-2175, USA
| | - Alicia A Taylor
- Ecological and Biological Sciences Practice, Exponent, Inc., Oakland, CA 94612, USA
| | - Jenny E Zenobio
- Department of Civil and Environmental Engineering, University of California, Irvine, CA 92697-2175, USA
| | - Yian Sun
- Department of Civil and Environmental Engineering, University of California, Irvine, CA 92697-2175, USA; Water-Energy Nexus Center, University of California, Irvine, CA 92697-2175, USA
| | - Ziwei Han
- Department of Civil and Environmental Engineering, University of California, Irvine, CA 92697-2175, USA
| | - Omobayo A Salawu
- Department of Civil and Environmental Engineering, University of California, Irvine, CA 92697-2175, USA
| | - Yurong Zhu
- Department of Chemical and Biomolecular Engineering, University of California, Irvine, CA 92697-2580, USA
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5
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Influence of Temperature on Denitrification and Microbial Community Structure and Diversity: A Laboratory Study on Nitrate Removal from Groundwater. WATER 2022. [DOI: 10.3390/w14030436] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Temperature is an extremely important environmental condition in the application of microbial denitrification for nitrate removal from groundwater. Understanding the nitrate removal efficiency of groundwater and the diversity, composition, and structure of microbial communities under different temperature conditions is of great significance for effective mitigation of groundwater nitrate pollution. This study investigated the effects of temperature on denitrification at 15 °C, 25 °C, 40 °C, and 45 °C. Moreover, the characteristics of microbial community structure and diversity were analyzed by combining high-throughput sequencing and polymerase chain reaction methods in order to fully clarify the denitrification efficiency under different temperature conditions. According to laboratory batch experiments and the findings of previous research, glucose was set as the carbon source and changes in “three nitrogen” indicators of the four temperature systems were mainly tested to clarify the effectiveness of nitrate removal. The maximum removal rates of nitrate nitrogen at 15 °C, 25 °C, 40 °C, and 45 °C were 44.05%, 87.03%, 99.26%, and 92.79%, respectively. Therefore, the most efficient nitrate removal can be achieved at 40℃. The Chao abundance indexes in the denitrification systems at 15 °C, 25 °C, 40 °C, and 45 °C were 1873, 352, 466, and 640, respectively. Therefore, the highest species richness was observed at 15 °C, but there were only a few dominant bacteria species. The composition of the bacterial community and the most dominant phylum varied at different temperatures. Among them, Gammaproteobacteria in Proteobacteria phylum plays an important role in the degradation of nitrate nitrogen. The relative abundance of Gammaproteobacteria at 15 °C, 25 °C, 40 °C, and 45 °C were 25.32%, 66.56%, 72.83%, and 3.47%. Tolumonas belongs to Gammaproteobacteria. The relative abundance of Tolumonas at 15 °C, 25 °C, 40 °C, and 45 °C were 9.41%, 65.47%, 62.49%, and 0.03%, respectively. The results of this study show that different temperature conditions affect the diversity, composition, and structure of the microbial community, thereby affecting the efficiency of denitrification for nitrate removal from groundwater.
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Tarhouchi S, Louafy R, El Atmani EH, Hlaïbi M. Kinetic control concept for the diffusion processes of paracetamol active molecules across affinity polymer membranes from acidic solutions. BMC Chem 2022; 16:2. [PMID: 35027092 PMCID: PMC8759197 DOI: 10.1186/s13065-021-00794-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Accepted: 12/28/2021] [Indexed: 11/23/2022] Open
Abstract
Background Paracetamol compound remains the most used pharmaceutical as an analgesic and antipyretic for pain and fever, often identified in aquatic environments. The elimination of this compound from wastewater is one of the critical operations carried out by advanced industries. Our work objective was to assess studies based on membrane processes by using two membranes, polymer inclusion membrane and grafted polymer membrane containing gluconic acid as an extractive agent for extracting and recovering paracetamol compound from aqueous solutions. Result The elaborated membrane characterizations were assessed using Fourier-transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). Kinetic and thermodynamic models have been applied to determine the values of macroscopic (P and J0), microscopic (D* and Kass), activation and thermodynamic parameters (Ea, ΔH#, ΔS#, ΔH#diss, and ΔH#th). All results showed that the PVA–GA was more performant than its counterpart GPM–GA, with apparent diffusion coefficient values (107D*) of 41.807 and 31.211 cm2 s−1 respectively, at T = 308 K. In addition, the extraction process for these membranes was more efficient at pH = 1. The relatively low values of activation energy (Ea), activation association enthalpy (ΔH≠ass), and activation dissociation enthalpy (ΔH≠diss) have indicated a kinetic control for the oriented processes studied across the adopted membranes much more than the energetic counterpart. Conclusion The results presented for the quantification of oriented membrane process ensured clean, sustainable, and environmentally friendly methods for the extraction and recovery of paracetamol molecule as a high-value substance. Supplementary Information The online version contains supplementary material available at 10.1186/s13065-021-00794-7.
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Affiliation(s)
- Sanae Tarhouchi
- Laboratoire Génie des Matériaux pour Environnement et Valorisation (GeMEV), Faculté des Sciences Ain Chock, Hasssan II University of Casablanca (UH2C), PB 5366, Maârif, Maroc.
| | - Rkia Louafy
- Laboratoire Génie des Matériaux pour Environnement et Valorisation (GeMEV), Faculté des Sciences Ain Chock, Hasssan II University of Casablanca (UH2C), PB 5366, Maârif, Maroc
| | - El Houssine El Atmani
- Laboratoire Génie des Matériaux pour Environnement et Valorisation (GeMEV), Faculté des Sciences Ain Chock, Hasssan II University of Casablanca (UH2C), PB 5366, Maârif, Maroc
| | - Miloudi Hlaïbi
- Laboratoire Génie des Matériaux pour Environnement et Valorisation (GeMEV), Faculté des Sciences Ain Chock, Hasssan II University of Casablanca (UH2C), PB 5366, Maârif, Maroc
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Chen X, Xu P, Yang C, Wang S, Lu Q, Sun X. Study of enhanced nitrogen removal efficiency and microbial characteristics of an improved two-stage A/O process. ENVIRONMENTAL TECHNOLOGY 2021; 42:4306-4316. [PMID: 32419659 DOI: 10.1080/09593330.2020.1754924] [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: 11/12/2019] [Accepted: 04/03/2020] [Indexed: 06/11/2023]
Abstract
During the cold winter in northern China, the temperature is generally below 8°C, and low water temperature significantly inhibits biological treatment processes, especially the biological denitrification process. To solve this problem, this study proposed an improved two-stage A/O process with built-in submerged biofilm modules. Experimental water was acquired from the Sanbaotun Wastewater Treatment Plant, which is situated in the city of Fushun, Liaoning Province. After one year of experimental research, the improved two-stage A/O process proved to be significantly better than the traditional two-stage A/O process, especially in winter. In the one-year experiment, the average removal rates of COD, TN, and NH4+-N in the improved two-stage A/O process were 85.2%, 77.6%, and 96.9%, respectively. Microbial properties of the process were studied by means of high-throughput sequencing. High-throughput sequencing was conducted on the biofilm of the improved two-stage A/O terminal aerobic tank and the activated sludge of the conventional two-stage A/O aerobic tank. The result showed that the microbial diversity and abundance of the biofilms were considerably higher than those of the activated sludge during stable operation in winter. Under low-temperature conditions, the main denitrifying bacteria of the improved two-stage A/O process was Terrimonas, belonging to the sphingolipid class of Bacteroides, and the main genus of nitrifying bacteria was Nitrospira, belonging to the nitrite oxidizing bacteria.
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Affiliation(s)
- Xiurong Chen
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai, PR People's Republic of China
- National Engineering Laboratory for High-concentration Refractory Organic Wastewater Treatment Technologies (NELHROWTT), East China University of Science and Technology, Shanghai, People's Republic of China
| | - Peng Xu
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai, PR People's Republic of China
- National Engineering Laboratory for High-concentration Refractory Organic Wastewater Treatment Technologies (NELHROWTT), East China University of Science and Technology, Shanghai, People's Republic of China
| | - Chenchen Yang
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai, PR People's Republic of China
- National Engineering Laboratory for High-concentration Refractory Organic Wastewater Treatment Technologies (NELHROWTT), East China University of Science and Technology, Shanghai, People's Republic of China
| | - Shanshan Wang
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai, PR People's Republic of China
- National Engineering Laboratory for High-concentration Refractory Organic Wastewater Treatment Technologies (NELHROWTT), East China University of Science and Technology, Shanghai, People's Republic of China
| | - Quanling Lu
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai, PR People's Republic of China
- National Engineering Laboratory for High-concentration Refractory Organic Wastewater Treatment Technologies (NELHROWTT), East China University of Science and Technology, Shanghai, People's Republic of China
| | - Xiaoli Sun
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai, PR People's Republic of China
- National Engineering Laboratory for High-concentration Refractory Organic Wastewater Treatment Technologies (NELHROWTT), East China University of Science and Technology, Shanghai, People's Republic of China
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Li J, Gao J, Zheng Q, Thai PK, Duan H, Mueller JF, Yuan Z, Jiang G. Effects of pH, Temperature, Suspended Solids, and Biological Activity on Transformation of Illicit Drug and Pharmaceutical Biomarkers in Sewers. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:8771-8782. [PMID: 34157837 DOI: 10.1021/acs.est.1c01516] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
In-sewer stability of biomarkers is a critical factor for wastewater-based epidemiology, as it could affect the accuracy of the estimated prevalence of substances in the community. The spatiotemporal variations of environmental and biological conditions in sewers can influence the transformation of biomarkers. To date, the relationship between environmental variables and biomarker stability in sewers is poorly understood. Therefore, this study evaluated the transformation of common illicit drug and pharmaceutical biomarkers in laboratory sewer reactors with different levels of pH, temperature, and suspended solids. The correlations between degradation rates of 14 biomarkers, 3 controlled environmental variables (pH, temperature, and suspended solids concentration), and 3 biological activity indicators (sulfide production rate, methane production rate, and the removal rate of soluble chemical oxygen demand (SCOD)) were assessed using correlation matrix, stepwise regression method, and principal component analysis. The consistent results affirmed the dominant effects of biological activities and pH on biomarker transformation in sewers, particularly for labile compounds, whereas the impact of temperature or suspended solids was less significant. This study enhances the understanding of factors affecting the fate of micropollutants in sewer systems and facilitates the interpretation of WBE results for assessing drug use and public health in communities.
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Affiliation(s)
- Jiaying Li
- Advanced Water Management Centre, The University of Queensland, St Lucia, QLD 4072, Australia
- Queensland Alliance for Environmental Health Sciences, The University of Queensland, Brisbane, QLD 4102, Australia
| | - Jianfa Gao
- Queensland Alliance for Environmental Health Sciences, The University of Queensland, Brisbane, QLD 4102, Australia
- College of Chemistry and Environmental Engineering, Shenzhen University, 1066 Xueyuan Avenue, Shenzhen, 518060, China
| | - Qiuda Zheng
- Queensland Alliance for Environmental Health Sciences, The University of Queensland, Brisbane, QLD 4102, Australia
| | - Phong K Thai
- Queensland Alliance for Environmental Health Sciences, The University of Queensland, Brisbane, QLD 4102, Australia
| | - Haoran Duan
- Advanced Water Management Centre, The University of Queensland, St Lucia, QLD 4072, Australia
| | - Jochen F Mueller
- Queensland Alliance for Environmental Health Sciences, The University of Queensland, Brisbane, QLD 4102, Australia
| | - Zhiguo Yuan
- Advanced Water Management Centre, The University of Queensland, St Lucia, QLD 4072, Australia
| | - Guangming Jiang
- Advanced Water Management Centre, The University of Queensland, St Lucia, QLD 4072, Australia
- School of Civil, Mining and Environmental Engineering, University of Wollongong, Wollongong, NSW 2522, Australia
- Illawarra Health and Medical Research Institute (IHMRI), University of Wollongong, Wollongong, NSW 2522, Australia
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A review of treatment methods for insensitive high explosive contaminated wastewater. Heliyon 2021; 7:e07438. [PMID: 34401549 PMCID: PMC8353291 DOI: 10.1016/j.heliyon.2021.e07438] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Revised: 03/01/2021] [Accepted: 06/25/2021] [Indexed: 11/28/2022] Open
Abstract
Insensitive high explosive materials (IHE) such as 3-nitro-1,2,4-triazol-5-one (NTO) and 2,4-dinitroanisole (DNAN) are increasingly being used in formulations of insensitive munitions alongside 1,3,5-trinitroperhydro-1,3,5-triazine (RDX). Load, assembly and packing (LAP) facilities that process munitions produce wastewater contaminated with IHE which must be treated before discharge. Some facilities can produce as much as 90,000 L of contaminated wastewater per day. In this review, methods of wastewater treatment are assessed in terms of their strengths, weaknesses, opportunities and threats for their use in production of IHE munitions including their limitations and how they could be applied to industrial scale LAP facilities. Adsorption is identified as a suitable treatment method, however the high solubility of NTO, up to 16.6 g.L−1 which is 180 times higher that of TNT, has the potential to exceed the adsorptive capacity of carbon adsorption systems. The key properties of the adsorptive materials along the selection of adsorption models are highlighted and recommendations on how the limitations of carbon adsorption systems for IHE wastewater can be overcome are offered, including the modification of carbons to increase adsorptive capacity or reduce costs.
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Asadi M, McPhedran K. Estimation of greenhouse gas and odour emissions from a cold region municipal biological nutrient removal wastewater treatment plant. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2021; 281:111864. [PMID: 33385907 DOI: 10.1016/j.jenvman.2020.111864] [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: 08/30/2020] [Revised: 11/14/2020] [Accepted: 12/16/2020] [Indexed: 06/12/2023]
Abstract
Seasonal temperature variations in cold regions worldwide lead to variable gas emissions from municipal wastewater treatment plants (MWTPs) due to changing wastewater temperatures in open-to-air treatment processes. The objective of this study was to determine the greenhouse gas (including carbon dioxide, CO2; methane, CH4; and nitrous oxide, N2O) and odour (including ammonia, NH3; and hydrogen sulphide, H2S) emission rate estimates (EREs) from the open-to-air processes of a biological nutrient removal (BNR) type MWTP in Saskatoon, SK, Canada. This MWTP experiences seasonal temperatures from -40 °C to 30 °C with the resultant wastewater temperatures considered herein of 13 °C and 17 °C being chosen based on monitoring data for winter and summer, respectively. Laboratory-scale reactors simulating anaerobic, anoxic, aerobic, and settling treatment processes were used to monitor gas EREs using wastewater samples taken from the analogous MWTP processes during the winter and summer seasons. Results indicated that the overall winter EREs for CO2, CH4, and N2O were 45,129 kg CO2/d, 21.9 kg CH4/d, and 3.20 kg N2O/d, respectively, while the H2S EREs were insignificant. The higher temperature for the summer samples resulted in increased EREs for CH4, N2O, and H2S EREs of 33.0 kg CH4/d, 3.87 kg N2O/d, and 2.29 kg H2S/d, respectively. However, the CO2 EREs were reduced to 37,794 kg CO2/d. Overall, the aerobic reactor was the dominant source of the GHG emissions for both seasons. In addition, studied changes in the aerobic reactor aeration rates (in reactor) and BNR treatment configurations (from site) further impacted the EREs.
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Affiliation(s)
- Mohsen Asadi
- Ph.D. Candidate, Department of Civil, Geological & Environmental Engineering, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Kerry McPhedran
- Associate Professor, Department of Civil, Geological & Environmental Engineering, University of Saskatchewan, Saskatoon, Saskatchewan, Canada.
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Shi Y, Lin H, Ma J, Zhu R, Sun W, Lin X, Zhang J, Zheng H, Zhang X. Degradation of tetracycline antibiotics by Arthrobacter nicotianae OTC-16. JOURNAL OF HAZARDOUS MATERIALS 2021; 403:123996. [PMID: 33265032 DOI: 10.1016/j.jhazmat.2020.123996] [Citation(s) in RCA: 51] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2020] [Revised: 08/04/2020] [Accepted: 09/12/2020] [Indexed: 06/12/2023]
Abstract
Microbial degradation is an important option for combating antibiotic pollution. Arthrobacter nicotianae OTC-16 was isolated as a novel tetracycline-degrading bacterium, which could degrade oxytetracycline/tetracycline (OTC/TET). Toxicity assessment indicated that this bacterium effectively converted OTC into byproducts with less toxicity to bacterial and algal indicators. Six degradation products of OTC were tentatively identified, and a potential biotransformation pathway was proposed that includes decarbonylation, reduction, and dehydration. Bioaugmentation of TC removal with this bacterium was further studied in various matrices. In aqueous media, strain OTC-16 accelerated OTC removal over a temperature range of 20-35 ℃, pH range of 6.0-9.0, and OTC concentration range of 25-150 mg L-1. The strain also facilitated the decrease of OTC and TET concentrations in both swine and chicken manures, with a maximum decrease of 91.54%, and increased the degradation of OTC in soils by 8.22-45.45%. A unique advantage of this bacterium in promoting OTC degradation in alkaline environments was demonstrated, where it successfully competed with the indigenous microbiota and largely decreased the relative abundances of the studied tetracycline resistance genes (tetB and tetW) in soil. This work offers a better understanding of the antibiotic bioaugmentation and new microbial sources.
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Affiliation(s)
- Yanke Shi
- College of Forest and Biotechnology, Zhejiang A & F University, Hangzhou 311300, China; The Institute of Environment, Resources, Soil and Fertilizers, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China.
| | - Hui Lin
- The Institute of Environment, Resources, Soil and Fertilizers, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China.
| | - Junwei Ma
- The Institute of Environment, Resources, Soil and Fertilizers, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China.
| | - Rongrong Zhu
- College of Forest and Biotechnology, Zhejiang A & F University, Hangzhou 311300, China; The Institute of Environment, Resources, Soil and Fertilizers, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China.
| | - Wanchun Sun
- The Institute of Environment, Resources, Soil and Fertilizers, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China.
| | - Xiaoyan Lin
- China National Rice Research Institute, Hangzhou 310006, China.
| | - Jin Zhang
- The Institute of Environment, Resources, Soil and Fertilizers, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China.
| | - Huabao Zheng
- College of Environmental and Resource Sciences, State Key Laboratory of Subtropical Silviculture, Zhejiang A & F University, Hangzhou 311300, China.
| | - Xin Zhang
- College of Forest and Biotechnology, Zhejiang A & F University, Hangzhou 311300, China.
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Li Z, Yu E, Zhang K, Gong W, Xia Y, Tian J, Wang G, Xie J. Water Treatment Effect, Microbial Community Structure, and Metabolic Characteristics in a Field-Scale Aquaculture Wastewater Treatment System. Front Microbiol 2020; 11:930. [PMID: 32655501 PMCID: PMC7325950 DOI: 10.3389/fmicb.2020.00930] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2020] [Accepted: 04/20/2020] [Indexed: 01/16/2023] Open
Abstract
Avoiding and mitigating the introduction of harmful effluent into the environment must be a key part of intensive industrial aquaculture development in order to minimize pollution impacts. We constructed a novel field-scale aquaculture wastewater treatment system (FAWTS) involving three-stage purification to efficiently remove nutrients from effluent wastewater. However, the mechanisms of nutrient attenuation in the FAWTS are still unclear. Since microbiota play an important role in the treatment of aquatic pollutants, we hypothesized that the different stages of FAWTS may have enriched various nutrient-metabolizing bacteria, with these promoting nutrient attenuation. We therefore tested microbial metabolic activity, microbial composition, and their metabolic potential using Biolog-GN2 microplate culture and high-throughput sequencing of prokaryotic 16S rRNA gene amplicons. Our results showed that the FAWTS displayed high removal efficiencies for chemical oxygen demand (COD, 74.4-91.2%), total nitrogen (TN, 66.9-86.8%), and total phosphorus (TP, 76.2-95.9%). Simultaneously, microbial metabolic activity for various carbon sources was significantly enhanced in FAWTS biofilms. Denitrifying and phosphorus-removing bacteria such as Rhodobacter were enriched in these biofilms, and genes participating in denitrification and the pathway from methylphosphonate to α-D-ribose-1,5-bisphosphate were increased in the biofilm communities. These results imply that the transformed multistep purification system effectively removed N, P, and COD from aquaculture wastewater by enhancing the bacterial communities involved in these processes. This suggests that contamination-free aquaculture is a feasible goal, and that microbial communities are central to pollutant removal.
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Affiliation(s)
- Zhifei Li
- Key Laboratory of Tropical and Subtropical Fishery Resource Application and Cultivation, Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, China
- Guangdong Ecological Remediation of Aquaculture Pollution Research Center, Guangzhou, China
| | - Ermeng Yu
- Key Laboratory of Tropical and Subtropical Fishery Resource Application and Cultivation, Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, China
- Guangdong Ecological Remediation of Aquaculture Pollution Research Center, Guangzhou, China
| | - Kai Zhang
- Key Laboratory of Tropical and Subtropical Fishery Resource Application and Cultivation, Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, China
- Guangdong Ecological Remediation of Aquaculture Pollution Research Center, Guangzhou, China
| | - Wangbao Gong
- Key Laboratory of Tropical and Subtropical Fishery Resource Application and Cultivation, Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, China
- Guangdong Ecological Remediation of Aquaculture Pollution Research Center, Guangzhou, China
| | - Yun Xia
- Key Laboratory of Tropical and Subtropical Fishery Resource Application and Cultivation, Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, China
- Guangdong Ecological Remediation of Aquaculture Pollution Research Center, Guangzhou, China
| | - Jingjing Tian
- Key Laboratory of Tropical and Subtropical Fishery Resource Application and Cultivation, Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, China
- Guangdong Ecological Remediation of Aquaculture Pollution Research Center, Guangzhou, China
| | - Guangjun Wang
- Key Laboratory of Tropical and Subtropical Fishery Resource Application and Cultivation, Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, China
- Guangdong Ecological Remediation of Aquaculture Pollution Research Center, Guangzhou, China
| | - Jun Xie
- Key Laboratory of Tropical and Subtropical Fishery Resource Application and Cultivation, Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, China
- Guangdong Ecological Remediation of Aquaculture Pollution Research Center, Guangzhou, China
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Xu Z, Fan Y, Wang T, Huang Y, MahmoodPoor Dehkordy F, Dai Z, Xia L, Dong Q, Bagtzoglou A, McCutcheon J, Lei Y, Li B. Towards high resolution monitoring of water flow velocity using flat flexible thin mm-sized resistance-typed sensor film (MRSF). WATER RESEARCH X 2019; 4:100028. [PMID: 31334492 PMCID: PMC6614588 DOI: 10.1016/j.wroa.2019.100028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2018] [Revised: 03/12/2019] [Accepted: 03/18/2019] [Indexed: 05/12/2023]
Abstract
Novel flexible thin mm-sized resistance-typed sensor film (MRSF) fabricated using ink-jet printing technology (IPT) was developed in this study to monitor water flow rate in pipelines in real time in situ mode. The mechanism of MRSF is that the mm-sized interdigitated electrodes made by printing silver nanoparticles on an elastic polyimide film bend under different flow rates, leading to variation of the resistance of the sensor at different degrees of curvature. Continuous flow tests showed that MRSF possessed a high accuracy (0.2 m/s) and excellent sensitivity (0.1447/ms-1). A model of sensor resistance and flow velocity was established to unfold the correlation between the fundamentals of fluid mechanics and the mechanic flexibility of sensor materials. An analytical model yielded a high coefficient of determination (R2 > 0.93) for the relationship between the resistance increment of the MRSF and the square of the flow velocity at the velocity range of 0.25-2 m/s. Furthermore, a temperature-correction model was developed to quantify the effect of water temperature on the sensor resistance readings. MRSF exhibited a low temperature coefficient of resistance (TCR, 0.001) at the water temperature range of 20-60 °C. Computational fluid dynamics (CFD) simulations using the finite element method were conducted and confirmed both the underlying load assumptions and the deformation characteristics of the sensor film under various flow and material conditions. High-resolution monitoring of water flow rate using MRSF technology was expected to save at least 50% energy consumption for a given unit, especially under flow fluctuation. MRSF possesses a great potential to perform real-time in situ monitoring at high accuracy with ultralow cost, thus enabling the feedback control at high spatiotemporal resolution to reduce the overall energy consumption in water and wastewater systems.
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Affiliation(s)
- Zhiheng Xu
- Department of Civil & Environmental Engineering, University of Connecticut, Storrs, Connecticut, 06269, United States
| | - Yingzheng Fan
- Department of Civil & Environmental Engineering, University of Connecticut, Storrs, Connecticut, 06269, United States
| | - Tianbao Wang
- Department of Civil & Environmental Engineering, University of Connecticut, Storrs, Connecticut, 06269, United States
| | - Yuankai Huang
- Department of Civil & Environmental Engineering, University of Connecticut, Storrs, Connecticut, 06269, United States
| | - Farzaneh MahmoodPoor Dehkordy
- Department of Civil & Environmental Engineering, University of Connecticut, Storrs, Connecticut, 06269, United States
| | - Zheqin Dai
- School of Energy and Environment, Southeast University, Nanjing, Jiangsu, 210096, China
| | - Lingling Xia
- Department of Chemical & Biomolecular Engineering, University of Connecticut, Storrs, Connecticut, 06269, United States
| | - Qiuchen Dong
- Department of Chemical & Biomolecular Engineering, University of Connecticut, Storrs, Connecticut, 06269, United States
| | - Amvrossios Bagtzoglou
- Department of Civil & Environmental Engineering, University of Connecticut, Storrs, Connecticut, 06269, United States
| | - Jeffrey McCutcheon
- Department of Chemical & Biomolecular Engineering, University of Connecticut, Storrs, Connecticut, 06269, United States
| | - Yu Lei
- Department of Chemical & Biomolecular Engineering, University of Connecticut, Storrs, Connecticut, 06269, United States
| | - Baikun Li
- Department of Civil & Environmental Engineering, University of Connecticut, Storrs, Connecticut, 06269, United States
- Corresponding author. Tel.: +860 486 2339.
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14
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Zhang X, Li H, Li Y, Guo F, Yang Z, Bai J. Do Wet-Dry Ratio and Fe-Mn System Affect Oxidation-Reduction Potential Nonlinearly in the Subsurface Wastewater Infiltration Systems? INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2018; 15:ijerph15122790. [PMID: 30544864 PMCID: PMC6313721 DOI: 10.3390/ijerph15122790] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/15/2018] [Revised: 12/03/2018] [Accepted: 12/05/2018] [Indexed: 11/16/2022]
Abstract
To understand characteristics of on-line oxidation-reduction potential (ORP) in a subsurface wastewater infiltration system (SWIS) under different intermittent influent conditions, ORP among five matrix depths at wet-dry ratios (Rwds) of 2:1, 1:1 and 1:2 with a hydraulic load of 0.10 m³·(m²·d)-1 were monitored. Results showed that the optimal Rwd for the SWIS was 1:1. In that case, ORP at 40 and 65 cm depths changed significantly, by 529 mV and 261 mV, respectively, from the inflow period to the dry period, which was conducive to the recovery of the oxidation environment. It was concluded that ORP varied nonlinearly in strongly aerobic and hypoxic environment. Wastewater was fed into the SWIS at 80 cm and dissolved oxygen diffused at the initial period of one cycle. As a consequence, ORP at 65 cm increased with water content increasing. However, ORP at 40 and 95 cm displayed inverse trends. Moreover, results showed that ORP decreased with Fe2+ and Mn2+ increasing under aerobic conditions (p < 0.05) because Fe2+ and Mn2+ moved with wastewater flow. Effluent met reuse requirements and no clogging was found in the SWIS during the operation.
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Affiliation(s)
- Xiaorong Zhang
- School of Resources and Civil Engineering, Northeastern University, Shenyang 110819, China.
| | - Haibo Li
- School of Resources and Civil Engineering, Northeastern University, Shenyang 110819, China.
| | - Yinghua Li
- School of Resources and Civil Engineering, Northeastern University, Shenyang 110819, China.
| | - Fei Guo
- School of Resources and Civil Engineering, Northeastern University, Shenyang 110819, China.
| | - Zhongxin Yang
- School of Resources and Civil Engineering, Northeastern University, Shenyang 110819, China.
| | - Jianing Bai
- School of Resources and Civil Engineering, Northeastern University, Shenyang 110819, China.
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15
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Vergili I, Golebatmaz U, Kaya Y, Gönder ZB, Hasar H, Yilmaz G. Performance and microbial shift during acidification of a real pharmaceutical wastewater by using an anaerobic sequencing batch reactor (AnSBR). JOURNAL OF ENVIRONMENTAL MANAGEMENT 2018; 212:186-197. [PMID: 29428653 DOI: 10.1016/j.jenvman.2018.01.058] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2017] [Revised: 01/17/2018] [Accepted: 01/21/2018] [Indexed: 06/08/2023]
Abstract
In this study, a lab-scale anaerobic sequencing batch reactor (AnSBR) was used for the acidification of a pharmaceutical wastewater sourced from etodolac chemical synthesis tanks. The effects of the organic loading rate (OLR), and etodolac and sulfate concentrations on the acidification rate and microbial community in AnSBR were investigated at 35 °C with a hydraulic retention time (HRT) of 37 h, a pH of 5, and OLRs up to 5.2 kgCOD/m3·day. The AnSBR accomplished a 60% acidification ratio and 50-60% etodolac removal at OLRs up to 2.6 kgCOD/m3·day. However, at OLR = 3.9 kgCOD/m3·day, acidification was not achieved due to sulfite inhibition; pre-ozonation was applied to overcome this sulfite inhibition. Although etodolac and COD removals were improved, the wastewater was not successfully acidified. Real-time polymerase chain reaction (Q-PCR) and fluorescent in situ hybridization (FISH) analyses revealed that acidification was inhibited by the dominance of sulfate reducing bacteria (SRB) over acidification bacteria in the AnSBR. However, increasing the OLR to 5.2 kgCOD/m3·day led to toxicity stress in the SRB due to increased sulfite concentrations. Sulfate load fundamentally affected acidification process and microbial community composition. The presence of etodolac with concentration up to 56 mg/L did not have a significant effect on VFA production and the microbial community.
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Affiliation(s)
- Ilda Vergili
- Istanbul University, Faculty of Engineering, Department of Environmental Engineering, Istanbul, Turkey.
| | - Ugur Golebatmaz
- Istanbul University, Faculty of Engineering, Department of Environmental Engineering, Istanbul, Turkey
| | - Yasemin Kaya
- Istanbul University, Faculty of Engineering, Department of Environmental Engineering, Istanbul, Turkey
| | - Z Beril Gönder
- Istanbul University, Faculty of Engineering, Department of Environmental Engineering, Istanbul, Turkey
| | - Halil Hasar
- Firat University, Faculty of Engineering, Department of Environmental Engineering, Elazig, Turkey
| | - Gulsum Yilmaz
- Istanbul University, Faculty of Engineering, Department of Environmental Engineering, Istanbul, Turkey
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16
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Duncan J, Bokhary A, Fatehi P, Kong F, Lin H, Liao B. Thermophilic membrane bioreactors: A review. BIORESOURCE TECHNOLOGY 2017; 243:1180-1193. [PMID: 28736143 DOI: 10.1016/j.biortech.2017.07.059] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2017] [Revised: 07/09/2017] [Accepted: 07/10/2017] [Indexed: 06/07/2023]
Abstract
This study undertakes a state-of-the-art review on thermophilic membrane bioreactors (ThMBRs). Thermophilic aerobic membrane bioreactors (ThAeMBR) and thermophilic anaerobic membrane bioreactors (ThAnMBR) have been widely tested for various high-temperature industrial wastewater treatments at lab- and pilot-scale studies and full-scale applications. The biological and membrane performances of the ThAeMBRs and ThAnMBRs could be better, comparable or poorer, as compared to the mesophilic ones. In general, sludge yield was much lower, biodegradation kinetic was higher, and microbial community was less diversity in the ThAeMBR and ThAnMBR systems. The results from the literature show that ThMBR technology has demonstrated many advantages and is a promising technology for industrial wastewater treatment and sludge digestion. Furthermore, challenges and opportunities of various ThMBRs for industrial applications are identified and discussed.
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Affiliation(s)
- Josh Duncan
- Department of Chemical Engineering, Lakehead University, 955 Oliver Road, Thunder Bay, ON P7B 5E1, Canada
| | - Alnour Bokhary
- Department of Chemical Engineering, Lakehead University, 955 Oliver Road, Thunder Bay, ON P7B 5E1, Canada
| | - Pedram Fatehi
- Department of Chemical Engineering, Lakehead University, 955 Oliver Road, Thunder Bay, ON P7B 5E1, Canada
| | - Fangong Kong
- College of Paper-making and Plant Resources Engineering, Qilu University of Technology, 3501 Daxue Road, Jinan, Shandong Province, PR China
| | - Hongjun Lin
- College of Geography and Environmental Sciences, Zhejiang Normal University, Jinhua 321004, PR China
| | - Baoqiang Liao
- Department of Chemical Engineering, Lakehead University, 955 Oliver Road, Thunder Bay, ON P7B 5E1, Canada; College of Paper-making and Plant Resources Engineering, Qilu University of Technology, 3501 Daxue Road, Jinan, Shandong Province, PR China.
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17
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Lutosławski K, Cibis E, Krzywonos M. The effect of temperature on the efficiency of aerobic biodegradation of sugar beet distillery stillage: Removal of pollution load and biogens. BRAZILIAN JOURNAL OF CHEMICAL ENGINEERING 2017. [DOI: 10.1590/0104-6632.20170344s20160417] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Affiliation(s)
| | - E. Cibis
- Wrocław University of Economics, Poland
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18
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Pal P. Treatment and Disposal of Pharmaceutical Wastewater: Toward the Sustainable Strategy. SEPARATION AND PURIFICATION REVIEWS 2017. [DOI: 10.1080/15422119.2017.1354888] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
- Parimal Pal
- Environment and Membrane Technology Laboratory, Department of Chemical Engineering, National Institute of Technology, Durgapur, West Bengal, India
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19
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Ren Y, Yang J, Chen S. The fate of a nitrobenzene-degrading bacterium in pharmaceutical wastewater treatment sludge. CHEMOSPHERE 2015; 141:13-18. [PMID: 26086561 DOI: 10.1016/j.chemosphere.2015.05.098] [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: 12/29/2014] [Revised: 05/09/2015] [Accepted: 05/29/2015] [Indexed: 06/04/2023]
Abstract
This paper describes the fate of a nitrobenzene-degrading bacterium, Klebsiella oxytoca NBA-1, which was isolated from a pharmaceutical wastewater treatment facility. The 90-day survivability of strain NBA-1 after exposure to sludge under anaerobic and aerobic conditions was investigated. The bacterium was inoculated into sludge amended with glucose and p-chloronitrobenzene (p-CNB) to compare the bacterial community variations between the modified sludge and nitrobenzene amendment. The results showed that glucose had no obvious effect on nitrobenzene biodegradation in the co-metabolism process, regardless of the presence/absence of oxygen. When p-CNB was added under anaerobic conditions, the biodegradation rate of nitrobenzene remained unchanged although p-CNB inhibited the production of aniline. The diversity of the microbial community increased and NBA-1 continued to be one of the dominant strains. Under aerobic conditions, the degradation rate of both nitrobenzene and p-CNB was only 20% of that under anaerobic conditions. p-CNB had a toxic effect on the microorganisms in the sludge so that most of the DGGE (denaturing gradient gel electrophoresis) bands, including that of NBA-1, began to disappear under aerobic conditions after 90days of exposure. These data show that the bacterial community was stable under anaerobic conditions and the microorganisms, including NBA-1, were more resistant to the adverse environment.
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Affiliation(s)
- Yuan Ren
- School of Environment and Energy, South China University of Technology, Higher Education Mega Center, Panyu District, Guangzhou 510006, PR China; The Key Laboratory of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, PR China; The Key Laboratory of Environmental Protection and Eco-Remediation of Guangdong Regular Higher Education Institutions, PR China.
| | - Juan Yang
- School of Environment and Energy, South China University of Technology, Higher Education Mega Center, Panyu District, Guangzhou 510006, PR China
| | - Shaoyi Chen
- School of Environment and Energy, South China University of Technology, Higher Education Mega Center, Panyu District, Guangzhou 510006, PR China
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20
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Romanazzi V, Traversi D, Lorenzi E, Gilli G. Effects of freezing storage on the DNA extraction and microbial evaluation from anaerobic digested sludges. BMC Res Notes 2015; 8:420. [PMID: 26347085 PMCID: PMC4562115 DOI: 10.1186/s13104-015-1407-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2014] [Accepted: 08/31/2015] [Indexed: 11/17/2022] Open
Abstract
Background The anaerobic digestion is one of the most spread renewable energy technology. The input biomasses included various environmental problematic wastes such as sludge coming from wastewater treatment plant (WWTP) and organic fraction of municipal solid waste (OFMSW). As biomolecular procedures have become important tools for the microbial characterisation of anaerobic samples coming from the reactors, it is crucial sampling and extracting properly DNA in order to employ such types of techniques. The current study is aimed to evaluate how freezing temperature and length of storage at −20 °C influence both the extracted DNA yield and microbial community quantifications from digested sludge samples collected at full-scale plants. Results From WWTP sludge samples, we observed a reduction of DNA concentration comparing fresh and stored samples for 10 days at −20 °C (ANOVA test p < 0.0001), with an estimated DNA loss of approximately 65 % for such types of samples, however the methanogen communities can be assessed respecting the fresh conditions. From OFMSW sludge samples, we observed a reduction in extracted DNA (−90 %), after 120 frozen days, while microbial communities are determined respecting the fresh conditions within 2 months of frozen storage. Conclusions The remarkable effect of frozen storage on sludge samples suggests as the better procedure to perform the DNA extraction from fresh sample. On the other hand it is not generally possible, so approximately 2 months of storage at −20 °C appears to be suitable time at which DNA concentrations remain sufficient to perform coherent microbial characterization through quantitative qRT-PCR.
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Affiliation(s)
- Valeria Romanazzi
- Hygiene Division, Department of Public Health and Pediatrics, University of Torino, Via Santena 5 bis, 10126, Turin, Italy.
| | - Deborah Traversi
- Hygiene Division, Department of Public Health and Pediatrics, University of Torino, Via Santena 5 bis, 10126, Turin, Italy.
| | - Eugenio Lorenzi
- SMAT, Società Metropolitana Acque Torino S.p.A., Corso XI Febbraio 14, 10152, Turin, Italy.
| | - Giorgio Gilli
- Hygiene Division, Department of Public Health and Pediatrics, University of Torino, Via Santena 5 bis, 10126, Turin, Italy.
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21
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Henry Ezec E, Mohamed Ku SRB, Hasnain Is M, Malakahmad A, Ibrahim SU. Chemical Oxygen Demand Removal from Wastewater by Integrated Bioreactor. ACTA ACUST UNITED AC 2015. [DOI: 10.3923/jest.2015.238.243] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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22
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Ashrafi O, Yerushalmi L, Haghighat F. Wastewater treatment in the pulp-and-paper industry: A review of treatment processes and the associated greenhouse gas emission. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2015; 158:146-57. [PMID: 25982876 DOI: 10.1016/j.jenvman.2015.05.010] [Citation(s) in RCA: 86] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2015] [Revised: 05/06/2015] [Accepted: 05/08/2015] [Indexed: 05/10/2023]
Abstract
Pulp-and-paper mills produce various types of contaminants and a significant amount of wastewater depending on the type of processes used in the plant. Since the generated wastewaters can be potentially polluting and very dangerous, they should be treated in wastewater treatment plants before being released to the environment. This paper reviews different wastewater treatment processes used in the pulp-and-paper industry and compares them with respect to their contaminant removal efficiencies and the extent of greenhouse gas (GHG) emission. It also evaluates the impact of operating parameters on the performance of different treatment processes. Two mathematical models were used to estimate GHG emission in common biological treatment processes used in the pulp-and-paper industry. Nutrient removal processes and sludge treatment are discussed and their associated GHG emissions are calculated. Although both aerobic and anaerobic biological processes are appropriate for wastewater treatment, their combination known as hybrid processes showed a better contaminant removal capacity at higher efficiencies under optimized operating conditions with reduced GHG emission and energy costs.
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Affiliation(s)
- Omid Ashrafi
- Department of Building, Civil and Environmental Engineering, Concordia University, 1455 Maisonneuve Blvd., West Montreal, Quebec, H3G 1M8, Canada
| | - Laleh Yerushalmi
- Department of Building, Civil and Environmental Engineering, Concordia University, 1455 Maisonneuve Blvd., West Montreal, Quebec, H3G 1M8, Canada
| | - Fariborz Haghighat
- Department of Building, Civil and Environmental Engineering, Concordia University, 1455 Maisonneuve Blvd., West Montreal, Quebec, H3G 1M8, Canada.
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23
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Pandit VU, Arbuj SS, Pandit YB, Naik SD, Rane SB, Mulik UP, Gosavi SW, Kale BB. Solar light driven dye degradation using novel organo–inorganic (6,13-pentacenequinone/TiO2) nanocomposite. RSC Adv 2015. [DOI: 10.1039/c4ra11920g] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The 6,13-pentacenequinone loaded TiO2 catalyst was successfully synthesized via simple wet-impregnation. The highest apparent rate constant was observed among the prepared catalysts is 5.2 × 10−2 min−1 using a PQ/TiO2 catalyst having 0.2 wt% PQ.
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Affiliation(s)
- Vikram U. Pandit
- Centre for Materials for Electronic Technology (C-MET)
- Govt of India
- Pune 411008
- India
| | - Sudhir S. Arbuj
- Centre for Materials for Electronic Technology (C-MET)
- Govt of India
- Pune 411008
- India
| | - Yashwant B. Pandit
- Organic and Hybrid Materials Lab
- Dept of Applied Chemistry
- Defence Institute of Advanced Technology (DIAT)
- Govt. of India
- Pune-411025
| | - Sonali D. Naik
- Centre for Materials for Electronic Technology (C-MET)
- Govt of India
- Pune 411008
- India
| | - Sunit B. Rane
- Centre for Materials for Electronic Technology (C-MET)
- Govt of India
- Pune 411008
- India
| | - Uttam P. Mulik
- Centre for Materials for Electronic Technology (C-MET)
- Govt of India
- Pune 411008
- India
| | | | - Bharat B. Kale
- Centre for Materials for Electronic Technology (C-MET)
- Govt of India
- Pune 411008
- India
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24
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Gadipelly C, Pérez-González A, Yadav GD, Ortiz I, Ibáñez R, Rathod VK, Marathe KV. Pharmaceutical Industry Wastewater: Review of the Technologies for Water Treatment and Reuse. Ind Eng Chem Res 2014. [DOI: 10.1021/ie501210j] [Citation(s) in RCA: 441] [Impact Index Per Article: 44.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Chandrakanth Gadipelly
- Department
of Chemical Engineering, Institute of Chemical Technology, Mumbai 400 019, India
| | - Antía Pérez-González
- Department
of Chemical and Biomolecular Engineering, University of Cantabria, Cantabria 39005, Spain
| | - Ganapati D. Yadav
- Department
of Chemical Engineering, Institute of Chemical Technology, Mumbai 400 019, India
| | - Inmaculada Ortiz
- Department
of Chemical and Biomolecular Engineering, University of Cantabria, Cantabria 39005, Spain
| | - Raquel Ibáñez
- Department
of Chemical and Biomolecular Engineering, University of Cantabria, Cantabria 39005, Spain
| | - Virendra K. Rathod
- Department
of Chemical Engineering, Institute of Chemical Technology, Mumbai 400 019, India
| | - Kumudini V. Marathe
- Department
of Chemical Engineering, Institute of Chemical Technology, Mumbai 400 019, India
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25
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Zheng M, Liao BQ. A comparative study on thermomechanical pulping pressate treatment using thermophilic and mesophilic sequencing batch reactors. ENVIRONMENTAL TECHNOLOGY 2014; 35:1409-1417. [PMID: 24701939 DOI: 10.1080/09593330.2013.869623] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
A comparative study on the treatment of thermomechanical pulping (TMP) pressate was conducted under thermophilic (55 degrees C) and mesophilic (30 degrees C) temperatures to explore in-mill biological treatment, with the intention to operate under heat-efficient conditions. The experimental study involved sequencing batch reactors (SBRs) operated over 114 days. Receiving a total influent chemical oxygen demand (COD) of 3700-4100 mg L(-1), the COD removal efficiencies of 80-90% and 75-85% were achieved for the mesophilic and thermophilic SBRs, respectively, at a hydraulic retention time (HRT) of 12 and 24h. Excellent sludge settleability (sludge volume index < 100 mL g(-1) mixed liquor suspended solids) was obtained at both thermophilic and mesophilic SBRs. A higher level of effluent suspended solids was observed under thermophilic conditions. The results support the feasibility of applying thermophilic biological treatment of TMP pressate. The treated effluent has the potential for subsequent reuse as process water after polishing, thus addressing the long-standing desire to develop water system closure for the pulp and paper mill operation.
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Removal of Pharmaceuticals by Conventional Wastewater Treatment Plants. ANALYSIS, REMOVAL, EFFECTS AND RISK OF PHARMACEUTICALS IN THE WATER CYCLE - OCCURRENCE AND TRANSFORMATION IN THE ENVIRONMENT 2013. [DOI: 10.1016/b978-0-444-62657-8.00008-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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27
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Influence of temperature and temperature shock on sludge properties, cake layer structure, and membrane fouling in a submerged anaerobic membrane bioreactor. J Memb Sci 2012. [DOI: 10.1016/j.memsci.2012.07.003] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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28
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Simstich B, Beimfohr C, Horn H. Lab scale experiments using a submerged MBR under thermophilic aerobic conditions for the treatment of paper mill deinking wastewater. BIORESOURCE TECHNOLOGY 2012; 122:11-16. [PMID: 22595101 DOI: 10.1016/j.biortech.2012.04.029] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2011] [Revised: 04/08/2012] [Accepted: 04/09/2012] [Indexed: 05/31/2023]
Abstract
This paper describes the results of laboratory experiments using a thermophilic aerobic MBR (TMBR) at 50 °C. An innovative use of submerged flat-sheet MBR modules to treat circuit wastewater from the paper industry was studied. Two experiments were conducted with a flux of 8-13 L/m(2)/h without chemical membrane cleaning. COD and BOD(5) elimination rates were 83% and 99%, respectively. Calcium was reduced from 110 to 180 mg/L in the inflow to 35-60 mg/L in the permeate. However, only negligible membrane scaling occurred. The observed sludge yield was very low and amounted to 0.07-0.29 g MLSS/g COD(eliminated). Consequently, the nutrient supply of ammonia and phosphate can be lower compared to a mesophilic process. Molecular-biological FISH analysis revealed a likewise high diversity of microorganisms in the TMBR compared to the mesophilic sludge used for start-up. Furthermore, ammonia-oxidising bacteria were detected at thermophilic operation.
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29
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Chen HJ, Lin YZ, Fanjiang JM, Fan C. Microbial community and treatment ability investigation in AOAO process for the optoelectronic wastewater treatment using PCR-DGGE biotechnology. Biodegradation 2012; 24:227-43. [DOI: 10.1007/s10532-012-9579-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2012] [Accepted: 07/19/2012] [Indexed: 11/30/2022]
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30
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Farhadi S, Aminzadeh B, Torabian A, Khatibikamal V, Alizadeh Fard M. Comparison of COD removal from pharmaceutical wastewater by electrocoagulation, photoelectrocoagulation, peroxi-electrocoagulation and peroxi-photoelectrocoagulation processes. JOURNAL OF HAZARDOUS MATERIALS 2012; 219-220:35-42. [PMID: 22464981 DOI: 10.1016/j.jhazmat.2012.03.013] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2011] [Revised: 03/03/2012] [Accepted: 03/06/2012] [Indexed: 05/31/2023]
Abstract
This work makes a comparison between electrocoagulation (EC), photoelectrocoagulation, peroxi-electrocoagulation and peroxi-photoelectrocoagulation processes to investigate the removal of chemical oxygen demand (COD) from pharmaceutical wastewater. The effects of operational parameters such as initial pH, current density, applied voltage, amount of hydrogen peroxide and electrolysis time on COD removal efficiency were investigated and the optimum operating range for each of these operating variables was experimentally determined. In electrocoagulation process, the optimum values of pH and voltage were determined to be 7 and 40 V, respectively. Desired pH and hydrogen peroxide concentration in the Fenton-based processes were found to be 3 and 300 mg/L, respectively. The amounts of COD, pH, electrical conductivity, temperature and total dissolved solids (TDS) were on-line monitored. Results indicated that under the optimum operating range for each process, the COD removal efficiency was in order of peroxi-electrocoagulation > peroxi-photoelectrocoagulation > photoelectrocoagulation>electrocoagulation. Finally, a kinetic study was carried out using the linear pseudo-second-order model and results showed that the pseudo-second-order equation provided the best correlation for the COD removal rate.
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Affiliation(s)
- Sajjad Farhadi
- Department of Civil and Environmental Engineering, Graduate Faculty of Environment, University of Tehran, Tehran, Iran.
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31
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Li T, Bo L, Yang F, Zhang S, Wu Y, Yang L. Comparison of the removal of COD by a hybrid bioreactor at low and room temperature and the associated microbial characteristics. BIORESOURCE TECHNOLOGY 2012; 108:28-34. [PMID: 22285900 DOI: 10.1016/j.biortech.2011.12.141] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/28/2011] [Revised: 12/27/2011] [Accepted: 12/28/2011] [Indexed: 05/31/2023]
Abstract
To improve the efficiency of wastewater treatment and characterize the microorganism communities, microorganisms were cultured and concentrated in hybrid bioreactors at a low temperature (~4 °C, low-temperature hybrid bioreactor, LTHB) and room temperature (~25 °C, room-temperature hybrid bioreactor, RTHB). The performance of the LTHB and RTHB in terms of COD removal efficiency, dehydrogenase activity and functional diversity of microbial communities were evaluated. The results show COD removal efficiency increased gradually over time from 39.76% to 66.27% for LTHB and fluctuated between 81.85% and 94.78% for RTHB. The dehydrogenase activity and microbial activity in LTHB was higher than those in RTHB, implying that microorganisms cultured at low temperature had higher activities and adaptabilities than those cultured at room temperature. This study suggests that hybrid bioreactors can treat wastewater at both low and room temperatures and provides valuable insight into the adaptation processes of the microorganisms during temperature changes.
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Affiliation(s)
- Tianling Li
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, No. 71, East Beijing Rd, Nanjing 210008, PR China
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32
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Chen Z, Wang H, Ren N, Cui M, Nie S, Hu D. Simultaneous removal and evaluation of organic substrates and NH3-N by a novel combined process in treating chemical synthesis-based pharmaceutical wastewater. JOURNAL OF HAZARDOUS MATERIALS 2011; 197:49-59. [PMID: 21974848 DOI: 10.1016/j.jhazmat.2011.09.053] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2011] [Revised: 08/30/2011] [Accepted: 09/14/2011] [Indexed: 05/31/2023]
Abstract
A full-scale novel combined anaerobic/micro-aerobic and two-stage aerobic biological process is used for the treatment of an actual chemical synthesis-based pharmaceutical wastewater containing amoxicillin. The anaerobic system is an up-flow anaerobic sludge blanket (UASB), the micro-aerobic system is a novel micro-aerobic hydrolysis acidification reactor (NHAR) and the two-stage aerobic process comprised cyclic activated sludge system (CASS) and biological contact oxidation tank (BCOT). The influent wastewater was high in COD, NH(3)-N varying daily 4016-13,093 mg-COD L(-1) and 156.4-650.2 mg-NH(3)-N L(-1), amoxicillin varying weekly between 69.1 and 105.4 mg-amoxicillin L(-1), respectively; Almost all the COD, NH(3)-N, amoxicillin were removed by the biological combined system, with removal percentages 97%, 93.4% and 97.2%, respectively, leaving around 104 mg-COD L(-1), 9.4 mg-NH(3)-N L(-1) and 2.6±0.8 mg-amoxicillin L(-1) in the final clarifier effluent. The performance evaluation of the wastewater treatment plant (WWTP) by mathematical statistic methods shown that at most of time effluent can meet the higher treatment discharge standard. In addition, the fate of amoxicillin in the full-scale WWTP and the amoxicillin removal rate of each different removal routes in UASB, NHAR, CASS, BCOT and final clarifier processes are investigated in this paper. The results show that biodegradation, adsorption and hydrolysis are the major mechanisms for amoxicillin removal.
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Affiliation(s)
- Zhaobo Chen
- School of Materials Science & Chemical Engineering, Harbin Engineering University, Harbin, China
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33
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Hai FI, Tessmer K, Nguyen LN, Kang J, Price WE, Nghiem LD. Removal of micropollutants by membrane bioreactor under temperature variation. J Memb Sci 2011. [DOI: 10.1016/j.memsci.2011.08.047] [Citation(s) in RCA: 100] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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34
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Chen Z, Wang H, Chen Z, Ren N, Wang A, Shi Y, Li X. Performance and model of a full-scale up-flow anaerobic sludge blanket (UASB) to treat the pharmaceutical wastewater containing 6-APA and amoxicillin. JOURNAL OF HAZARDOUS MATERIALS 2011; 185:905-913. [PMID: 20970923 DOI: 10.1016/j.jhazmat.2010.09.106] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2010] [Revised: 08/20/2010] [Accepted: 09/28/2010] [Indexed: 05/30/2023]
Abstract
A full-scale test was conducted with an up-flow anaerobic sludge blanket (UASB) pre-treating pharmaceutical wastewater containing 6-aminopenicillanic acid (6-APA) and amoxicillin. The aim of the study is to investigate the performance of UASB in the condition of a high chemical oxygen demand (COD) loading rate from 12.57 to 21.02 kgm(-3)d(-1) and a wide pH from 5.57 to 8.26, in order to provide a reference for treating the similar chemical synthetic pharmaceutical wastewater containing 6-APA and amoxicillin. The results demonstrated that the UASB average percentage reduction in COD, 6-APA and amoxicillin were 52.2%, 26.3% and 21.6%, respectively. In addition, three models, built on the back propagation neural network (BPNN) theory and linear regression techniques were developed for the simulation of the UASB system performance in the biodegradation of pharmaceutical wastewater containing 6-APA and amoxicillin. The average error of COD, 6-APA and amoxicillin were -0.63%, 2.19% and 5.40%, respectively. The results indicated that these models built on the BPNN theory were well-fitted to the detected data, and were able to simulate and predict the removal of COD, 6-APA and amoxicillin by UASB.
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Affiliation(s)
- Zhiqiang Chen
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China
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35
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Héry M, Sanguin H, Perez Fabiel S, Lefebvre X, Vogel TM, Paul E, Alfenore S. Monitoring of bacterial communities during low temperature thermal treatment of activated sludge combining DNA phylochip and respirometry techniques. WATER RESEARCH 2010; 44:6133-6143. [PMID: 20673948 DOI: 10.1016/j.watres.2010.07.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2009] [Revised: 05/30/2010] [Accepted: 07/04/2010] [Indexed: 05/29/2023]
Abstract
Sludge reduction is one of the major challenges in biological wastewater treatment. One approach is to increase the sludge degradation yield together with the biodegradation kinetics. Among the various sludge pretreatment strategies proposed, thermal pretreatment at around 65 °C was described as promising. The enhancement in the biodegradation activity due to the selection of thermophilic hydrolytic bacteria was proposed, but further experiments are needed to demonstrate the specific role of these bacteria. In this study, concentrated activated sludge grown at 20 °C was subjected to thermal treatment at 65 °C for different periods. The originality of the work relied on a polyphasic approach based on the correlation between kinetics (chemical oxygen demand, COD; mixed liquor suspended solids, MLSS), bacterial activity (respirometry) and bacterial community structure (phylochip monitoring) in order to characterize the mechanisms involved in the thermal reduction of sludge. The bacterial activity in the aeration basin decreased to a very low level when recycling sludge was treated at 65 °C from 13 to 60 h, but then, started to increase after 60 h. In parallel to these fluctuations in activity, a drastic shift occurred in the bacterial community structure with the selection of thermophilic bacteria (mainly related to genera Paenibacillus and Bacillus), which are known for their specific hydrolases.
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Affiliation(s)
- Marina Héry
- Université de Toulouse, F-31077, Toulouse, France.
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36
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Chan YJ, Chong MF, Law CL. Effects of Temperature on Aerobic Treatment of Anaerobically Digested Palm Oil Mill Effluent (POME). Ind Eng Chem Res 2010. [DOI: 10.1021/ie901952m] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Yi Jing Chan
- School of Chemical and Environmental Engineering, Faculty of Engineering, The University of Nottingham Malaysia Campus, Jalan Broga, 43500 Semenyih, Selangor, Malaysia
| | - Mei Fong Chong
- School of Chemical and Environmental Engineering, Faculty of Engineering, The University of Nottingham Malaysia Campus, Jalan Broga, 43500 Semenyih, Selangor, Malaysia
| | - Chung Lim Law
- School of Chemical and Environmental Engineering, Faculty of Engineering, The University of Nottingham Malaysia Campus, Jalan Broga, 43500 Semenyih, Selangor, Malaysia
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37
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Li J, Jin Z. Effect of hypersaline aniline-containing pharmaceutical wastewater on the structure of activated sludge-derived bacterial community. JOURNAL OF HAZARDOUS MATERIALS 2009; 172:432-438. [PMID: 19656627 DOI: 10.1016/j.jhazmat.2009.07.031] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2009] [Revised: 07/07/2009] [Accepted: 07/08/2009] [Indexed: 05/28/2023]
Abstract
In order to explore the effect of hypersaline aniline-containing pharmaceutical wastewater on the structure of activated sludge-derived bacterial community, RAPD-PCR and PCR-DGGE techniques were used to analyze the change of bacterial community diversity and structure during the acclimation to different concentrations of two types of wastewater. Different bacterial community structures and significant shift in the bacterial community diversity were observed during the acclimation of wastewater. The number of bacterial species and the abundance of bacteria acclimated to different concentration of wastewater decreased when the concentration increased. The trends of bacterial community diversity indices revealed by RAPD or DGGE profiles were different. The change of bacterial community diversity might be due to the adaptation and mutation under selection issues in the acclimation of wastewater. The relationship between diversity indices and the content of chemical oxygen demand (COD), chloride, salinity and aniline based on RAPD and DGGE data indicated that the change of the bacterial community diversity might not be due to a single factor but might be due to the integrated effects of all the contaminants in the wastewater. Phylogenic trees based on RAPD and DGGE fingerprints were different, indicating that the effect of wastewaters A and B on the bacterial community structure was different, which might be due to the characteristics of wastewater.
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Affiliation(s)
- Junmin Li
- Institute of Ecology, Taizhou University, 605 Dongfang Dadao, Linhai 317000, PR China.
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38
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Xing ZP, Sun DZ. Treatment of antibiotic fermentation wastewater by combined polyferric sulfate coagulation, Fenton and sedimentation process. JOURNAL OF HAZARDOUS MATERIALS 2009; 168:1264-1268. [PMID: 19345002 DOI: 10.1016/j.jhazmat.2009.03.008] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2008] [Revised: 03/02/2009] [Accepted: 03/03/2009] [Indexed: 05/27/2023]
Abstract
Attempts were made in this study to examine the combined polyferric sulfate (PFS) coagulation, Fenton and sedimentation process for treatment of non-degradable antibiotic fermentation wastewater. The experimental results indicated that 66.6% of color and 72.4% of chemical oxygen demand (COD) were removed under the optimum conditions of PFS dosage 200mg/L and pH 4.0. In addition, optimal parameters of Fenton process were determined to be 150 mg/L of H(2)O(2) dosage, 120 mg/L of FeSO(4) and 1h of reaction time. When Fenton treated effluent was controlled at pH 7.0, the pollutants could be further removed by sedimentation process. The overall color, COD and suspended solids (SS) removal reached 97.3%, 96.9% and 86.7% under selected conditions, respectively. Thus this study might offer an effective way for wastewater treatment of antibiotics manufacturer and pharmaceutical industry.
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Affiliation(s)
- Zi-Peng Xing
- School of Municipal and Environmental Engineering, Harbin Institute of Technology, Harbin, China
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39
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Microbial communities and biodegradation in lab-scale BTEX-contaminated groundwater remediation using an oxygen-releasing reactive barrier. Bioprocess Biosyst Eng 2009; 33:383-91. [DOI: 10.1007/s00449-009-0336-7] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2009] [Accepted: 05/24/2009] [Indexed: 10/20/2022]
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40
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41
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Lin CW, Lai CY, Chen LH, Chiang WF. Microbial community structure during oxygen-stimulated bioremediation in phenol-contaminated groundwater. JOURNAL OF HAZARDOUS MATERIALS 2007; 140:221-9. [PMID: 16876942 DOI: 10.1016/j.jhazmat.2006.06.083] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2006] [Revised: 05/19/2006] [Accepted: 06/20/2006] [Indexed: 05/11/2023]
Abstract
This research explored the changes in genetic diversity and spatial distribution of microbial communities in association with the changes in phenol concentration during a bioremediation process. Results using the traditional plate count method indicated an increase of average bacteria densities in groundwater from 10(4) to 10(7)CFUml(-1) initially to 10(7) to 10(9)CFUml(-1) after remediation. The diversity and stability of phenol-degrading bacterial communities were investigated by using single-strand-conformation polymorphism (SSCP) genetic profile analysis of 16S rDNA fragments amplified from groundwater samples. The molecular data showed a high degree of genetic similarity between communities from certain monitoring wells during the early phases of remediation, probably due to similar initial physical conditions among wells. Molecular signatures of several cultivated phenol-degrading bacterial strains could be seen in most groundwater profiles throughout the study period, suggesting that these strains were indigenous to the study site. It was also observed that the species diversity of these microbial communities increased as the phenol levels in the groundwater decreased during the 9-month study period, and recovered to the pre-treatment levels after the remediation program was completed.
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Affiliation(s)
- Chi-Wen Lin
- Department of Environmental Engineering, Da-Yeh University, 112 Shan-Jiau Road, Da-Tsuen, Changhua 515, Taiwan.
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42
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Zitomer DH, Duran M, Albert R, Guven E. Thermophilic aerobic granular biomass for enhanced settleability. WATER RESEARCH 2007; 41:819-25. [PMID: 17229452 DOI: 10.1016/j.watres.2006.11.037] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2006] [Revised: 11/17/2006] [Accepted: 11/25/2006] [Indexed: 05/13/2023]
Abstract
Aerobic biological wastewater treatment at thermophilic (ca. 55 degrees C) temperatures notoriously produces biomass that flocculates poorly or not at all. Contrary to this, thermophilic aerobic biomass that settled well in sequencing batch reactors was cultured with sludge volume index (SVI) values as low as 60mL/g. A mixture of granular and flocculant biomass resulted when closed reactors were sparged with recirculated reactor headspace gas containing some air, whereas a conventionally aerated control reactor sparged with air alone contained dispersed growth that did not flocculate. Maximum granule diameter was from 1.2 to 1.9mm, and granule resistance to disintegration was comparable to aerobic mesophilic granules. Two bacteria were isolated and identified as Anoxybacillus flavothermus and Pseudoxanthomonas taiwanensis as determined by partial 16S rDNA sequencing. Anoxybacilli species are alkaliphilic or alkalitolerant, with the type species having an obligate requirement for carbonate, even when grown on glucose. We postulate that high alkalinity and CO(2) may select for a population of aerobic thermophilies that flocculates and granulates.
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Affiliation(s)
- Daniel H Zitomer
- Civil and Environmental Engineering Department, Marquette University, Milwaukee, WI 53201, USA.
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43
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Quesnel D, Nakhla G. Optimization of the aerobic biological treatment of thermophilically treated refractory wastewater. JOURNAL OF HAZARDOUS MATERIALS 2005; 125:221-30. [PMID: 16005148 DOI: 10.1016/j.jhazmat.2005.05.033] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2005] [Revised: 05/19/2005] [Accepted: 05/24/2005] [Indexed: 05/03/2023]
Abstract
A pilot scale conventional activated sludge was operated for over 600 days to study its effectiveness at further remediating the effluent of an existing industrial site's thermophilic biological treatment stage. During the course of the study, the activated sludge was able to further biodegrade the contaminants in the incoming industrial wastewater in terms of both BOD and nitrogen reductions at varying hydraulic and solids retention times, despite elevated concentrations of soluble copper being present. A limiting hydraulic retention time (HRT) for BOD removal of 1.5 days was observed as well as the loss of nitrification occurred at a solids retention time (SRT) of approximately 6 days. Biokinetic coefficients were determined with the maximum rate of substrate utilization per unit mass of microorganisms, k, of 0.14 mgVSS/(mgsBOD-d) and the Monod half velocity constant, K(s), of 9.4 mgsBOD/L. Simultaneous nitrification and denitrification (SND) of the nitrogenous compounds found in this wastewater was observed throughout the majority of the experimentation while the bulk DO in the system was greater than 1 mg/L. The activated sludge was estimated to contain soluble copper on the order of 1 mg/L throughout the course of operation with no apparent detriment to nitrification. Additionally, the activated sludge was able to biologically remove the main solvents found in the influent wastewater. The removals of trace levels of N-nitrosodimethylamine (NDMA) were also observed.
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Affiliation(s)
- David Quesnel
- University of Western Ontario, Department of Chemical & Biochemical Engineering, London, Ont., Canada
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44
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Cheng C, Phipps D, Alkhaddar RM. Treatment of spent metalworking fluids. WATER RESEARCH 2005; 39:4051-63. [PMID: 16112709 DOI: 10.1016/j.watres.2005.07.012] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2004] [Revised: 07/01/2005] [Accepted: 07/08/2005] [Indexed: 05/04/2023]
Abstract
Metalworking fluids (MWFs) are widely used for cooling and lubricating during the machining process. The worldwide annual usage is estimated to exceed 2 x 10(9)l and the waste could be more than ten times the usage, as the MWFs have to be diluted prior to use. For UK industry the disposal cost is estimated to be up to pound16 million per year. Used MWFs cause high levels of contamination and rancid odours due to the presence of complex chemicals, biocides, etc., so that their treatment and final disposal must be handled carefully. Conventionally this has been done by combined physical and chemical methods but, with tightened legislation, these routes are no longer acceptable. Now, biological treatment is being increasingly adopted as it seems to offer an alternative with the potential for significant cost saving. However, there are significant difficulties in operating bioreactors, such as maintenance of the stability of the microbial communities present in activated sludge plants (ASP). In order to resolve these problems, four major areas need to be considered: (1) the composition of the spent MWF and its inherent biodegradability, (2) the recalcitrant compounds existing in waste MWFs and their impact on microbes, (3) the nature of the microbial consortia and means of optimising it, e.g, temperature and the practical design of the bioreactor and (4) the requirements for nutrient supplements and optimal control conditions. The potential importance of understanding the microbial community has been studied by the use of molecular biological techniques such as polymerase chain reaction (PCR), denaturing gradient gel electrophoresis (DGGE), fatty acid methyl ester (FAME) and fluorescent in situ hybridization (FISH). The application of attached biofilm bioreactors and thermophilic aerobic technology (TAT) has also been studied. This review describes recent advances in each of these areas.
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Affiliation(s)
- Christina Cheng
- School of Biomolecular Sciences, Liverpool John Moores University, Byrom Street, Liverpool L3 3AF, UK.
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45
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Rodríguez-Martínez J, Martínez-Amador SY, Garza-García Y. Comparative anaerobic treatment of wastewater from pharmaceutical, brewery, paper and amino acid producing industries. J Ind Microbiol Biotechnol 2005; 32:691-6. [PMID: 15937696 DOI: 10.1007/s10295-005-0244-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2004] [Accepted: 04/20/2005] [Indexed: 11/29/2022]
Abstract
This study concerned the anaerobic treatment of five different industrial wastewaters with a diverse and complex chemical composition. The kinetics of biotransformation of this wastewater at different chemical oxygen demand (COD) were studied in a batch reactor. Wastewater from an amino acid producing industry (Fermex) and from a tank that received several types of wastewaters (collector) contained 0.83 g l(-1) and 0.085 g l(-1) sulfate, respectively. During the study period of 20 days, methane formation was observed in all types of wastewaters. Studies on COD biodegradation showed the reaction velocity was higher for Fermex wastewater and lower for collector wastewater, with values of 0.0022 h(-1) and 0.0011 h(-1), respectively. A lower methanogenic activity of 0.163 g CH4 day(-1) g(-1) volatile suspended solids (VSS) and 0.20 g CH4 day(-1) g(-1) VSS, respectively, was observed for paper producing and brewery wastewater. Adapted granular sludge showed the best biodegradation of COD during the 20-day period. The sulfate-reducing activity in pharmaceutical and collector wastewater was studied. A positive effect of sulfate-reducing activity on methanogenic activity was noted for both types of wastewaters, both of which contained sulfate ions. All reactions of methane generation for the tested industrial wastewaters were first-order. The results of this study suggest that the tested wastewaters are amenable to anaerobic treatment.
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Affiliation(s)
- Jesús Rodríguez-Martínez
- Biotechnology Department, Chemistry Faculty, Autonomous University of Coahuila, Boulevard V. Carranza, Saltillo, 25000, Coahuila, Mexico.
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46
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Suvilampi J, Lehtomäki A, Rintala J. Comparative study of laboratory-scale thermophilic and mesophilic activated sludge processes. WATER RESEARCH 2005; 39:741-750. [PMID: 15743618 DOI: 10.1016/j.watres.2004.11.025] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2003] [Revised: 03/18/2004] [Accepted: 11/16/2004] [Indexed: 05/24/2023]
Abstract
Laboratory-scale mesophilic (20-35 degrees C) and thermophilic (55 degrees C) activated sludge processes (ASPs) treating diluted molasses wastewater were compared in effluent quality, removal of different COD fractions, sludge yield, floc size, and sludge settleability. The effect of polyaluminium chloride (PAC) with high cationic charge on sludge settleability and effluent quality was also studied. In the ASPs, the hydraulic retention time was 12h in both processes, corresponding to a volumetric loading rate of 3.2+/-1.0 kg COD(filt) m(-3)d(-1). The mesophilic ASP gave 79+/-18% and 90+/-2% and the thermophilic ASP gave 50+/-6% and 67+/-11% total COD (COD(tot)) and GF/A-filtered COD (COD(filt)) removals, respectively. The higher COD values in the thermophilic effluent were due to dispersed particles, such as free bacteria, measured as colloidal COD (COD(col)=difference between soluble COD (COD(sol)) and COD(filt)). Both ASPs gave high (90%) COD(sol) removals. Aeration (24-h) of the thermophilic ASP effluent at 35 degrees C reduced the density of the free bacteria by half, which was also measured as 90% COD(col) removal. Post-aeration of thermophilic effluent at 55 degrees C had no influence either on the density of free bacteria or on the COD(col) values. The use of PAC did not increase COD(tot) or COD(filt) removals in either process, but reduced the mesophilic and increased the thermophilic sludge volume index values.
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Affiliation(s)
- J Suvilampi
- Watrec Ltd., Koulukatu 13, FIN-30100, Forssa, Finland.
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Quesnel D, Nakhla G. Characterization and treatability of aerobic bacterial thermophilically treated wastewater by a conventional activated sludge and granular activated carbon. WATER RESEARCH 2005; 39:677-87. [PMID: 15707641 DOI: 10.1016/j.watres.2004.11.010] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2004] [Revised: 10/25/2004] [Accepted: 11/22/2004] [Indexed: 05/08/2023]
Abstract
An industrial wastewater that was pretreated by an aerobic thermophilic bacterial consortium (THE) was subjected to additional treatability studies by granular activated carbon (GAC) and a conventional activated sludge (CAS). The removal of dissolved organic carbon (DOC) in both systems was generally found to be similar. While GAC was able to attain better effluent concentrations of toluene and methyl isobutyl ketone (MIBK), the CAS was much more efficient at removing acetone. Furthermore, unlike the GAC, the performance of the CAS was not influenced by the high degree of variability in the influent wastewater. Characterization of the influent thermophilic wastewater using gas chromatography-mass spectroscopy (GC/MS) was performed to quantify the micropollutants as well as to evaluate removal efficiencies from the GAC and CAS systems.
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Affiliation(s)
- David Quesnel
- Department of Chemical & Biochemical Engineering, University of Western Ontario, London, Ont., Cannda N6A 5B9
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Xia S, Wang F, Fu Y, Yang D, Ma X. Biodiversity analysis of microbial community in the chem-bioflocculation treatment process. Biotechnol Bioeng 2005; 89:656-9. [PMID: 15674825 DOI: 10.1002/bit.20339] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Total DNA was directly extracted from environmental samples and amplified with polymerase chain reaction (PCR) technique. The PCR products were fingerprinted via denaturing gradient gel electrophoresis (DGGE). Significant differences were observed in the microbial community structures between traditional treatment process and chem-bioflocculation process. The microbial community structure shift at different sampling locations in chem-bioflocculation process and on two typical operational conditions was studied. 16S rDNA V3 regions of some dominant species were sequenced and the species were identified. The microbial communities were stable in both the chem-bioflocculation process and the activated sludge process under various experimental conditions presented in this work. The attached growth treatment process was less stable when operational conditions changed.
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Affiliation(s)
- Siqing Xia
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Engineering, Tongji University, 200092 Shanghai, China.
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Juteau P, Tremblay D, Ould-Moulaye CB, Bisaillon JG, Beaudet R. Swine waste treatment by self-heating aerobic thermophilic bioreactors. WATER RESEARCH 2004; 38:539-546. [PMID: 14723922 DOI: 10.1016/j.watres.2003.11.001] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Pig manure represents a very high-strength wastewater that is well suited for a self-heating aerobic thermophilic treatment. Here we report the use of 59-L Aerobic Thermophilic Sequencing Batch Reactors (AT-SBR) to study the treatment of pig manure with a HRT of 6 days. Temperatures up to 75 degrees C were reached without external heating by using Venturi-type aerators but these conditions were detrimental for the respiratory activity of the microflora. For COD removal, better performances were achieved when the temperature was limited to 50 degrees C. However, higher temperatures increased the rate of phosphorus crystallisation and the volatilisation of ammonia. A temperature of 50 degrees C was enough to eliminate faecal coliforms and Campylobacter spp., but 60 degrees C was needed for the efficient destruction of Clostridium perfringens. Consequently, an operating temperature of 60 degrees C appears to be a good compromise. Under these conditions, the BOD(5) decreases from 50.5 to 1.0 g L(-1), yielding a 98% removal.
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Affiliation(s)
- Pierre Juteau
- INRS-Institut Armand-Frappier, Université du Québec, 531 Boulevard des Prairies, Laval, Québec, Canada H7V 1B7.
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Klatt CG, LaPara TM. Aerobic biological treatment of synthetic municipal wastewater in membrane-coupled bioreactors. Biotechnol Bioeng 2003; 82:313-20. [PMID: 12599258 DOI: 10.1002/bit.10572] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Membrane-coupled bioreactors (MBRs) offer many benefits compared to conventional biological wastewater treatment systems; however, their performance characteristics are poorly understood. Laboratory-scale MBRs were used to study bacterial adaptations in physiology and community structure. MBRs were fed a mixture of starch, gelatin, and polyoxyethylene-sorbitan monooleate to simulate the polysaccharide, protein, and lipid components of municipal wastewater. Physiological adaptations were detected by measuring ectoenzyme activity while structural dynamics were studied by denaturing gradient gel electrophoresis of PCR-amplified 16S rRNA gene fragments. As cell biomass accumulated in the MBRs, pollutant removal efficiency initially improved and then stabilized with respect to effluent concentrations of chemical oxygen demand, protein, and carbohydrate. Comparison of the MBR effluent to filtered reactor fluid indicated that a portion of the observed pollutant removal was due to filtration by the membrane rather than microbial activity. The rates of ectoenzyme-mediated polysaccharide (alpha-glucosidase) and protein (leucine aminopeptidase) hydrolysis became relatively constant once pollutant removal efficiency stabilized. However, the maximum rate of lipid hydrolysis (heptanoate esterase) concomitantly increased more than 10-fold. Similarly, alpha-glucosidase and leucine aminopeptidase ectoenzyme affinities were relatively constant, while the heptanoate esterase affinity increased more than 30-fold. Community analysis revealed that a substantial community shift occurred within the first 7 days of operation. A Flavobacterium-like bacterial population dominated the community (>50% of total band intensity) and continued to do so for the remainder of the experiment.
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Affiliation(s)
- Christian G Klatt
- University of Minnesota, Department of Civil Engineering, 500 Pillsbury Drive SE, Minneapolis, Minnesota 55455, USA
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