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Zhao P, Zhao S, Wang HG, Lu M, Li ZH. Encapsulation of bacteria in different stratified extracellular polymeric substances and its implications for performance enhancement and resource recovery. WATER RESEARCH 2022; 220:118684. [PMID: 35661510 DOI: 10.1016/j.watres.2022.118684] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/11/2022] [Revised: 05/24/2022] [Accepted: 05/27/2022] [Indexed: 05/06/2023]
Abstract
Simultaneous recovery of biopolymers and enhanced bio-reactor performance are promising options for sustainable wastewater treatment, and the bioactivity of sludge after biopolymer extraction is thus critical for the performance of the system. To this end, stratified extracellular polymeric substances (EPS), including slime, loosely bound EPS (LB-EPS), and tightly bound EPS (TB-EPS), were extracted, and the bioactivities of the consequent extraction residues were assessed using aerobic respirogram, kinetic, and flow cytometry (FCM). After the initial weak extraction of slime, the particle size distribution of the sludge significantly decreased, and subsequent extractions of LB-EPS and TB-EPS produced an equivalent size distribution. In contrast, the fractal dimension decreased after each extraction, suggesting that LB-EPS and TB-EPS affected the compactness of flocs rather than the size. The aerobic bacteria distribution estimated using respirogram shows that slime mainly encapsulated heterotrophs while LB-EPS mainly encapsulated nitrifiers. In addition, the ammonia-nitrogen affinity coefficient decreased from 1.79 to 0.28 mg/L when slime was removed, thereby encouraging the activities of autotrophic nitrifiers. Further removal of LB-EPS induced high energy dispersion as the maintenance coefficient m and the metabolic dispersion index μ/m increased from 0.11 to 0.22 and 0.44 to 0.63, respectively. Meanwhile, the yield rate decreased from 0.77 to 0.66. Although pellets that resulted from TB-EPS extraction were not aerobically active as described by respirogram and growth curves, they were still metabolically active as measured by live/dead cell counting and redox sensor green signal. These pellets used more energy for maintenance as indicated by the high maintenance coefficient than those residual after either slime or LB-EPS extraction. In addition, the variation in bacteria community distribution across flocs was related to the variation in temperatures, suggesting that the inner part of a floc might be hotter than the outer side. Therefore, compared to bacteria in the raw sludge, the viable bacteria bounded in LB-EPS and TB-EPS convert more energy to heat rather than growth. These results indicate that energy was dispersed as metabolic heat for the LB-EPS extracted sludge, and removal of LB-EPS favored thermogenesis and sludge reduction. Based on the above findings, a simultaneously EPS-recovery and performance enhancement configuration is thus proposed, which holds great promise for the integration of next-generation wastewater treatment plants.
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Affiliation(s)
- Pian Zhao
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Song Zhao
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Hai-Guang Wang
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Meng Lu
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Zhi-Hua Li
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China.
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Sánchez-Zurano A, Rossi S, Fernández-Sevilla JM, Acién-Fernández G, Molina-Grima E, Ficara E. Respirometric assessment of bacterial kinetics in algae-bacteria and activated sludge processes. BIORESOURCE TECHNOLOGY 2022; 352:127116. [PMID: 35398212 DOI: 10.1016/j.biortech.2022.127116] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2022] [Revised: 03/30/2022] [Accepted: 04/01/2022] [Indexed: 06/14/2023]
Abstract
Algae-bacteria (AB) consortia can be exploited for effective wastewater treatment, based on photosynthetic oxygenation to reduce energy requirements for aeration. While algal kinetics have been extensively evaluated, bacterial kinetics in AB systems are still based on parameters taken from the activated sludge models, lacking an experimental validation for AB consortia. A respirometric procedure was therefore proposed, to estimate bacterial kinetics in both activated sludge and AB, under different conditions of temperature, pH, dissolved oxygen, and substrate availability. Bacterial activities were differently influenced by operational/environmental conditions, suggesting that the adoption of typical activated sludge parameters could be inadequate for AB modelling. Indeed, respirometric results show that bacteria in AB consortia were adapted to a wider range of conditions, compared to activated sludge, confirming that a dedicated calibration of bacterial kinetics is essential for effectively modelling AB systems, and respirometry was proven to be a powerful and reliable tool to this purpose.
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Affiliation(s)
- A Sánchez-Zurano
- Department of Chemical Engineering, University of Almería, 04120 Almería, Spain, CIESOL Solar Energy Research Centre, Joint Centre University of Almería-CIEMAT, 04120 Almería, Spain
| | - S Rossi
- Politecnico di Milano, Dept. of Civil and Environmental Engineering, P.zza L. da Vinci, 32, 20133 Milan, Italy
| | - J M Fernández-Sevilla
- Department of Chemical Engineering, University of Almería, 04120 Almería, Spain, CIESOL Solar Energy Research Centre, Joint Centre University of Almería-CIEMAT, 04120 Almería, Spain
| | - G Acién-Fernández
- Department of Chemical Engineering, University of Almería, 04120 Almería, Spain, CIESOL Solar Energy Research Centre, Joint Centre University of Almería-CIEMAT, 04120 Almería, Spain
| | - E Molina-Grima
- Department of Chemical Engineering, Universidad de Almería, 04120 Almería, Spain
| | - E Ficara
- Politecnico di Milano, Dept. of Civil and Environmental Engineering, P.zza L. da Vinci, 32, 20133 Milan, Italy.
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Simmons EL, Bond MC, Koskella B, Drescher K, Bucci V, Nadell CD. Biofilm Structure Promotes Coexistence of Phage-Resistant and Phage-Susceptible Bacteria. mSystems 2020; 5:e00877-19. [PMID: 32576653 PMCID: PMC7311319 DOI: 10.1128/msystems.00877-19] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Accepted: 05/29/2020] [Indexed: 01/21/2023] Open
Abstract
Encounters among bacteria and their viral predators (bacteriophages) are among the most common ecological interactions on Earth. These encounters are likely to occur with regularity inside surface-bound communities that microbes most often occupy in natural environments. Such communities, termed biofilms, are spatially constrained: interactions become limited to near neighbors, diffusion of solutes and particulates can be reduced, and there is pronounced heterogeneity in nutrient access and physiological state. It is appreciated from prior theoretical work that phage-bacteria interactions are fundamentally different in spatially structured contexts, as opposed to well-mixed liquid culture. Spatially structured communities are predicted to promote the protection of susceptible host cells from phage exposure, and thus weaken selection for phage resistance. The details and generality of this prediction in realistic biofilm environments, however, are not known. Here, we explore phage-host interactions using experiments and simulations that are tuned to represent the essential elements of biofilm communities. Our simulations show that in biofilms, phage-resistant cells-as their relative abundance increases-can protect clusters of susceptible cells from phage exposure, promoting the coexistence of susceptible and phage-resistant bacteria under a large array of conditions. We characterize the population dynamics underlying this coexistence, and we show that coexistence is recapitulated in an experimental model of biofilm growth measured with confocal microscopy. Our results provide a clear view into the dynamics of phage resistance in biofilms with single-cell resolution of the underlying cell-virion interactions, linking the predictions of canonical theory to realistic models and in vitro experiments of biofilm growth.IMPORTANCE In the natural environment, bacteria most often live in communities bound to one another by secreted adhesives. These communities, or biofilms, play a central role in biogeochemical cycling, microbiome functioning, wastewater treatment, and disease. Wherever there are bacteria, there are also viruses that attack them, called phages. Interactions between bacteria and phages are likely to occur ubiquitously in biofilms. We show here, using simulations and experiments, that biofilms will in most conditions allow phage-susceptible bacteria to be protected from phage exposure, if they are growing alongside other cells that are phage resistant. This result has implications for the fundamental ecology of phage-bacteria interactions, as well as the development of phage-based antimicrobial therapeutics.
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Affiliation(s)
- Emilia L Simmons
- Department of Biological Sciences, Dartmouth, Hanover, New Hampshire, USA
| | - Matthew C Bond
- Department of Biological Sciences, Dartmouth, Hanover, New Hampshire, USA
| | - Britt Koskella
- Department of Integrative Biology, University of California, Berkeley, Berkeley, California, USA
| | - Knut Drescher
- Max Planck Institute for Terrestrial Microbiology, Marburg, Germany
- Department of Physics, Philipps-Universität Marburg, Marburg, Germany
| | - Vanni Bucci
- Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, Worcester, Massachusetts, USA
| | - Carey D Nadell
- Department of Biological Sciences, Dartmouth, Hanover, New Hampshire, USA
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Hernandez-Martinez GR, Ortiz-Alvarez D, Perez-Roa M, Urbina-Suarez NA, Thalasso F. Multiparameter analysis of activated sludge inhibition by nickel, cadmium, and cobalt. JOURNAL OF HAZARDOUS MATERIALS 2018; 351:63-70. [PMID: 29510328 DOI: 10.1016/j.jhazmat.2018.02.032] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2017] [Revised: 02/14/2018] [Accepted: 02/15/2018] [Indexed: 06/08/2023]
Abstract
Activated sludge processes are often inhibited by nickel, cadmium, and cobalt. The inhibitory effect of these heavy metals on a synthetic wastewater treatment process was tested through pulse microrespirometry; i.e., pulse of substrate injected in a microreactor system. The inhibitory effect was tested under different conditions including the heavy metals, substrate and biomass concentrations, and exposure time. The inhibitory effect was quantified by the percentage of inhibition, half saturation constant (KS), inhibition constant (KI), and maximum oxygen uptake rate (OURmax). The results indicated that, in a range of concentration from 0 to 40 mg L-1, the three heavy metals exerted an uncompetitive and incomplete inhibitory effect, with a maximum inhibition of 67, 57, and 53% for Ni, Co, and Cd, respectively. An increase of the biomass concentration by 620% resulted in a decrease of the inhibition by 47 and 69% for Co and Cd, respectively, while no effect was observed on Ni inhibition. An increase of the substrate concentration by 87% resulted in an increase of the inhibition by 24, 70, and 47% for Ni, Co and Cd, respectively. In the case of nickel and cadmium, an increase in the exposure time to the heavy metals also increased the inhibition.
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Affiliation(s)
- Gabriel R Hernandez-Martinez
- Centro de Investigación y de Estudios Avanzados del IPN (Cinvestav), Departamento de Biotecnología y Bioingeniería, Av. IPN 2508, San Pedro Zacatenco, 07360, Mexico City, Mexico
| | - Daniela Ortiz-Alvarez
- Centro de Investigación y de Estudios Avanzados del IPN (Cinvestav), Departamento de Biotecnología y Bioingeniería, Av. IPN 2508, San Pedro Zacatenco, 07360, Mexico City, Mexico; Universidad Francisco de Paula Santander, Av. Gran Colombia 12E-96, San José de Cúcuta, Colombia
| | - Michael Perez-Roa
- Centro de Investigación y de Estudios Avanzados del IPN (Cinvestav), Departamento de Biotecnología y Bioingeniería, Av. IPN 2508, San Pedro Zacatenco, 07360, Mexico City, Mexico; Universidad Francisco de Paula Santander, Av. Gran Colombia 12E-96, San José de Cúcuta, Colombia
| | | | - Frederic Thalasso
- Centro de Investigación y de Estudios Avanzados del IPN (Cinvestav), Departamento de Biotecnología y Bioingeniería, Av. IPN 2508, San Pedro Zacatenco, 07360, Mexico City, Mexico.
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Arnaldos M, Rehman U, Naessens W, Amerlinck Y, Nopens I. Understanding the effects of bulk mixing on the determination of the affinity index: consequences for process operation and design. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2018; 77:576-588. [PMID: 29431702 DOI: 10.2166/wst.2017.550] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The main objective of this study is to demonstrate the importance of mixing conditions as a source of inconsistencies between half-saturation indices in comparable systems (e.g. conventional activated sludge, membrane bioreactor) when operated at different conditions or different scales. As proof-of-principle, an exemplary system consisting of the second vessel of a hybrid respirometer has been studied. The system has been modeled both using an integrated computational fluid dynamics (CFD)-biokinetic model (assumed to represent the physical system) and a tanks-in-series, completely stirred tank reactor biokinetic model (representing the applied model). The results show that different mixing conditions cause deviations in the half-saturation indices calculated when matching the applied model to the physical system performance. Additionally, sensor location has been shown to impact the calculation of half-saturation indices in the respirometric system. This will only become more pronounced at larger scales. Thus, mixing conditions clearly affect operation and design of wastewater treatment reactors operated at low substrate concentrations. Both operation and design can be improved with the development and application of integrated CFD-biokinetic or compartmental models.
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Affiliation(s)
- Marina Arnaldos
- Department of Mathematical Modelling, Statistics and Bioinformatics, BIOMATH, Coupure Links 653, Gent 9000, Belgium E-mail: ; Cetaqua Water Technology Center, Carretera d'Esplugues 75, 08940 Cornella de Llobregat, Barcelona, 22, El Prat del Llobregat (Barcelona) 08820, Spain
| | - Usman Rehman
- Department of Mathematical Modelling, Statistics and Bioinformatics, BIOMATH, Coupure Links 653, Gent 9000, Belgium E-mail:
| | - Wouter Naessens
- Department of Mathematical Modelling, Statistics and Bioinformatics, BIOMATH, Coupure Links 653, Gent 9000, Belgium E-mail:
| | - Youri Amerlinck
- Department of Mathematical Modelling, Statistics and Bioinformatics, BIOMATH, Coupure Links 653, Gent 9000, Belgium E-mail:
| | - Ingmar Nopens
- Department of Mathematical Modelling, Statistics and Bioinformatics, BIOMATH, Coupure Links 653, Gent 9000, Belgium E-mail:
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Vital-Jacome M, Dochain D, Thalasso F. Microrespirometric model calibration applied to wastewater processes. Biochem Eng J 2017. [DOI: 10.1016/j.bej.2017.10.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Ordaz A, Sánchez M, Rivera R, Rojas R, Zepeda A. Respirometric response and microbial succession of nitrifying sludge to m-cresol pulses in a sequencing batch reactor. Biodegradation 2016; 28:81-94. [DOI: 10.1007/s10532-016-9779-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2016] [Accepted: 11/26/2016] [Indexed: 10/20/2022]
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Reino C, Suárez-Ojeda ME, Pérez J, Carrera J. Kinetic and microbiological characterization of aerobic granules performing partial nitritation of a low-strength wastewater at 10 °C. WATER RESEARCH 2016; 101:147-156. [PMID: 27262119 DOI: 10.1016/j.watres.2016.05.059] [Citation(s) in RCA: 66] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2016] [Revised: 05/17/2016] [Accepted: 05/17/2016] [Indexed: 06/05/2023]
Abstract
A granular airlift reactor enriched in ammonia oxidizing bacteria (AOB) was operated at 10 °C performing stable partial nitritation in the long-term. The reactor treated a synthetic low-strength influent during 250 days with an average nitrogen loading rate of 0.63 ± 0.06 g N L(-1) d(-1). Nitrate production was barely detected, being the average concentration in the effluent of 0.6 ± 0.3 mg N-NO3 L(-1). Furthermore, a suitable effluent for a subsequent reactor performing the anammox process was achieved. A maximum specific growth rate as high as 0.63 ± 0.05 d(-1) was determined by performing kinetic experiments with the granular sludge in a chemostat and fitting the results to the Monod model. Pyrosequencing analysis showed a high enrichment in AOB (41 and 65% of the population were identified as Nitrosomonas genus on day 98 and 233, respectively) and an effective repression of nitrite oxidizing bacteria in the long-term. Pyrosequencing analysis also identified the coexistence of nitrifying bacteria and heterotrophic psychrotolerant microorganisms in the granular sludge. Some psychrotolerant microorganisms are producers of cryoprotective extracellular polymeric substances that could explain the better survival of the whole consortia at cold temperatures.
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Affiliation(s)
- Clara Reino
- GENOCOV Research Group, Department of Chemical, Biological and Environmental Engineering, School of Engineering, Universitat Autònoma de Barcelona, Ed. Q-Campus UAB, 08193, Bellaterra, Barcelona, Spain
| | - María Eugenia Suárez-Ojeda
- GENOCOV Research Group, Department of Chemical, Biological and Environmental Engineering, School of Engineering, Universitat Autònoma de Barcelona, Ed. Q-Campus UAB, 08193, Bellaterra, Barcelona, Spain
| | - Julio Pérez
- GENOCOV Research Group, Department of Chemical, Biological and Environmental Engineering, School of Engineering, Universitat Autònoma de Barcelona, Ed. Q-Campus UAB, 08193, Bellaterra, Barcelona, Spain; Department of Biotechnology, Delft University of Technology, Julianalaan 67, Delft, 2628 BC, The Netherlands
| | - Julián Carrera
- GENOCOV Research Group, Department of Chemical, Biological and Environmental Engineering, School of Engineering, Universitat Autònoma de Barcelona, Ed. Q-Campus UAB, 08193, Bellaterra, Barcelona, Spain.
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Vital-Jacome M, Buitrón G, Moreno-Andrade I, Garcia-Rea V, Thalasso F. Microrespirometric determination of the effectiveness factor and biodegradation kinetics of aerobic granules degrading 4-chlorophenol as the sole carbon source. JOURNAL OF HAZARDOUS MATERIALS 2016; 313:112-121. [PMID: 27054670 DOI: 10.1016/j.jhazmat.2016.02.077] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Revised: 02/20/2016] [Accepted: 02/27/2016] [Indexed: 06/05/2023]
Abstract
In this study, a microrespirometric method was used, i.e., pulse respirometry in microreactors, to characterize mass transfer and biodegradation kinetics in aerobic granules. The experimental model was an aerobic granular sludge in a sequencing batch reactor (SBR) degrading synthetic wastewater containing 4-chlorophenol as the sole carbon source. After 15 days of acclimation, the SBR process degraded 4-chlorophenol at a removal rate of up to 0.9kg CODm(-3)d(-1), and the degradation kinetics were well described by the Haldane model. The microrespirometric method consisted of injecting pulses of 4-chlorophenol into the 24 wells of a microreactor system containing the SBR samples. From the respirograms obtained, the following five kinetic parameters were successfully determined during reactor operation: (i) Maximum specific oxygen uptake rate, (ii) substrate affinity constant, (iii) substrate inhibition constant, (iv) maximum specific growth rate, and (v) cell growth yield. Microrespirometry tests using granules and disaggregated granules allowed for the determination of apparent and intrinsic parameters, which in turn enabled the determination of the effectiveness factor of the granular sludge. It was concluded that this new high-throughput method has the potential to elucidate the complex biological and physicochemical processes of aerobic granular biosystems.
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Affiliation(s)
- Miguel Vital-Jacome
- Department of Biotechnology and Bioengineering, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (Cinvestav-IPN), Av. IPN 2508, 07360 México DF, México
| | - Germán Buitrón
- Laboratory for Research on Advanced Process for Water Treatment, Unidad Académica Juriquilla, Instituto de Ingeniería, Universidad Nacional Autónoma de México, Blvd. Juriquilla 3001, Querétaro 76320, México
| | - Ivan Moreno-Andrade
- Laboratory for Research on Advanced Process for Water Treatment, Unidad Académica Juriquilla, Instituto de Ingeniería, Universidad Nacional Autónoma de México, Blvd. Juriquilla 3001, Querétaro 76320, México
| | - Victor Garcia-Rea
- Laboratory for Research on Advanced Process for Water Treatment, Unidad Académica Juriquilla, Instituto de Ingeniería, Universidad Nacional Autónoma de México, Blvd. Juriquilla 3001, Querétaro 76320, México
| | - Frederic Thalasso
- Department of Biotechnology and Bioengineering, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (Cinvestav-IPN), Av. IPN 2508, 07360 México DF, México.
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Arnaldos M, Amerlinck Y, Rehman U, Maere T, Van Hoey S, Naessens W, Nopens I. From the affinity constant to the half-saturation index: understanding conventional modeling concepts in novel wastewater treatment processes. WATER RESEARCH 2015; 70:458-470. [PMID: 25576693 DOI: 10.1016/j.watres.2014.11.046] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2014] [Revised: 11/25/2014] [Accepted: 11/26/2014] [Indexed: 06/04/2023]
Abstract
The "affinity constant" (KS) concept is applied in wastewater treatment models to incorporate the effect of substrate limitation on process performance. As an increasing number of wastewater treatment processes rely on low substrate concentrations, a proper understanding of these so-called constants is critical in order to soundly model and evaluate emerging treatment systems. In this paper, an in-depth analysis of the KS concept has been carried out, focusing on the different physical and biological phenomena that affect its observed value. By structuring the factors influencing half-saturation indices (newly proposed nomenclature) into advectional, diffusional and biological, light has been shed onto some of the apparent inconsistencies present in the literature. Particularly, the importance of non-ideal mixing as a source of variability between observed KS values in different systems has been illustrated. Additionally, discussion on the differences existent between substrates that affect half-saturation indices has been carried out; it has been shown that the observed KS for some substrates will reflect transport or biological limitations more than others. Finally, potential modeling strategies that could alleviate the shortcomings of the KS concept have been provided. These could be of special importance when considering the evaluation and design of emerging wastewater treatment processes.
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Affiliation(s)
- Marina Arnaldos
- BIOMATH, Department of Mathematical Modelling, Statistics and Bio-informatics, Coupure Links 653, 9000 Gent, Belgium; Acciona Agua S.A., R&D Department, Av. De les Garrigues 22, 08820 El Prat del Llobregat, Barcelona, Spain
| | - Youri Amerlinck
- BIOMATH, Department of Mathematical Modelling, Statistics and Bio-informatics, Coupure Links 653, 9000 Gent, Belgium
| | - Usman Rehman
- BIOMATH, Department of Mathematical Modelling, Statistics and Bio-informatics, Coupure Links 653, 9000 Gent, Belgium
| | - Thomas Maere
- BIOMATH, Department of Mathematical Modelling, Statistics and Bio-informatics, Coupure Links 653, 9000 Gent, Belgium
| | - Stijn Van Hoey
- BIOMATH, Department of Mathematical Modelling, Statistics and Bio-informatics, Coupure Links 653, 9000 Gent, Belgium
| | - Wouter Naessens
- BIOMATH, Department of Mathematical Modelling, Statistics and Bio-informatics, Coupure Links 653, 9000 Gent, Belgium
| | - Ingmar Nopens
- BIOMATH, Department of Mathematical Modelling, Statistics and Bio-informatics, Coupure Links 653, 9000 Gent, Belgium.
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Ramirez-Vargas R, Vital-Jacome M, Camacho-Perez E, Hubbard L, Thalasso F. Characterization of oxygen transfer in a 24-well microbioreactor system and potential respirometric applications. J Biotechnol 2014; 186:58-65. [DOI: 10.1016/j.jbiotec.2014.06.031] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2014] [Revised: 05/15/2014] [Accepted: 06/25/2014] [Indexed: 12/01/2022]
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12
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Microrespirometric characterization of activated sludge inhibition by copper and zinc. Biodegradation 2014; 25:867-79. [DOI: 10.1007/s10532-014-9706-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2014] [Accepted: 08/05/2014] [Indexed: 10/24/2022]
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