1
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Zhang L, Wang H, Wu A, Yang K, Zhang X, Guo J. Effect of flocculant dosage on the settling properties and underflow concentration of thickener for flocculated tailing suspensions. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2023; 88:304-320. [PMID: 37452549 PMCID: wst_2023_191 DOI: 10.2166/wst.2023.191] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/18/2023]
Abstract
Flocculation is important in the thickening process to improve the underflow concentration in thickeners for tailing suspensions. Traditional zone settling velocity (ZSV) functions ignore the effect of flocculant dosage on the ZSV and the thickening behavior of thickeners. To investigate the effect of flocculant dosage on the settling flux function, a series of batch settling tests were conducted at various flocculant dosages for unclassified and fine tailings. The correlation among flocculant dosage, solid fraction, and parameters in the ZSV function was revealed. Moreover, a simulation of continuous thickening based on the ZSV function was performed. Results indicated that flocculation influenced settling velocity and floc density. With an increased flocculant dosage, the settling velocity of floc increased, resulting in increased underflow concentration. Conversely, floc density decreased due to a stronger particle-particle interaction, leading to a decreased underflow concentration.
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Affiliation(s)
- Lianfu Zhang
- Anhui Engineering Research Center of Exploitation and Utilization of Closed/Abandoned Mine Resources, Anhui University of Science and Technology, Huainan 232001, China; School of Mining Engineering, Anhui University of Science and Technology, Huainan 232001, China; School of Civil & Resource Engineering, University of Science and Technology Beijing, Beijing 100083, China E-mail:
| | - Hongjiang Wang
- School of Civil & Resource Engineering, University of Science and Technology Beijing, Beijing 100083, China
| | - Aixiang Wu
- School of Civil & Resource Engineering, University of Science and Technology Beijing, Beijing 100083, China
| | - Ke Yang
- School of Mining Engineering, Anhui University of Science and Technology, Huainan 232001, China
| | - Xi Zhang
- School of Civil & Resource Engineering, University of Science and Technology Beijing, Beijing 100083, China
| | - Jiabin Guo
- School of Civil & Resource Engineering, University of Science and Technology Beijing, Beijing 100083, China
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2
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Feilin H, Mingwei S. Design, simulation, and laboratory test of a single sludge drainage pipe for wastewater treatment sedimentation tank. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2020; 82:905-917. [PMID: 33031069 DOI: 10.2166/wst.2020.397] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
This study develops a novel design scheme based on engineering fluid mechanics for the single-pipe-type sludge drainage mechanism of sedimentation tanks in the wastewater treatment industry. A laboratory-scale clarifier is fabricated for experimental verification. Sludge drainage ratio and suspended solids (SS) of inflow are selected as two factors for laboratory experiments, and SS values are measured to evaluate the performance of the sludge drainage pipe. Experiment data show that the designed single sludge drainage pipe can successfully achieve the supposed task with a coefficient of variation (CV) of SS less than 8.5%. The variation scope of CV from 1.5% to 8.3% suggests that the sludge drainage performance is relatively steady. Nine sets of 3D computational fluid dynamic (CFD) simulations, which is based on the inhomogeneous Eulerian-Eulerian multiphase model, were conducted for a comprehensive exploration and assessment. Results reveal noticeable deviations of the characteristics of the fluid in the outermost orifice of the sludge drainage pipe from the designed value. Although the fluid velocity through each orifice is matched with the designed values, the mass flowrate differs with a maximum of four times the designed value and a standard deviation of 0.4 of hole among the nine simulations. This study also suggests some considerations in the design process and routine operation of the single-pipe-type sludge drainage system.
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Affiliation(s)
- Hao Feilin
- College of Biology and Environmental Engineering, Zhejiang Shuren University, Hangzhou 310015, China E-mail:
| | - Shen Mingwei
- College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou 310058, China
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3
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Baalbaki Z, Torfs E, Yargeau V, Vanrolleghem PA. Predicting the fate of micropollutants during wastewater treatment: Calibration and sensitivity analysis. THE SCIENCE OF THE TOTAL ENVIRONMENT 2017; 601-602:874-885. [PMID: 28582733 DOI: 10.1016/j.scitotenv.2017.05.072] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2016] [Revised: 04/11/2017] [Accepted: 05/08/2017] [Indexed: 06/07/2023]
Abstract
The presence of micropollutants in the environment and their toxic impacts on the aquatic environment have raised concern about their inefficient removal in wastewater treatment plants. In this study, the fate of micropollutants of four different classes was simulated in a conventional activated sludge plant using a bioreactor micropollutant fate model coupled to a settler model. The latter was based on the Bürger-Diehl model extended for the first time to include micropollutant fate processes. Calibration of model parameters was completed by matching modelling results with full-scale measurements (i.e. including aqueous and particulate phase concentrations of micropollutants) obtained from a 4-day sampling campaign. Modelling results showed that further biodegradation takes place in the sludge blanket of the settler for the highly biodegradable caffeine, underlining the need for a reactive settler model. The adopted Monte Carlo based calibration approach also provided an overview of the model's global sensitivity to the parameters. This analysis showed that for each micropollutant and according to the dominant fate process, a different set of one or more parameters had a significant impact on the model fit, justifying the selection of parameter subsets for model calibration. A dynamic local sensitivity analysis was also performed with the calibrated parameters. This analysis supported the conclusions from the global sensitivity and provided guidance for future sampling campaigns. This study expands the understanding of micropollutant fate models when applied to different micropollutants, in terms of global and local sensitivity to model parameters, as well as the identifiability of the parameters.
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Affiliation(s)
- Zeina Baalbaki
- Department of Chemical Engineering, McGill University, 3610 University St., Montreal, QC H3A 0C5, Canada
| | - Elena Torfs
- modelEAU, Département de génie civil et de génie des eaux, Université Laval, 1065 Avenue de la médecine, Québec City, QC, G1V 0A6, Canada.
| | - Viviane Yargeau
- Department of Chemical Engineering, McGill University, 3610 University St., Montreal, QC H3A 0C5, Canada
| | - Peter A Vanrolleghem
- modelEAU, Département de génie civil et de génie des eaux, Université Laval, 1065 Avenue de la médecine, Québec City, QC, G1V 0A6, Canada
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4
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Bürger R, Careaga J, Diehl S. A simulation model for settling tanks with varying cross-sectional area. CHEM ENG COMMUN 2017. [DOI: 10.1080/00986445.2017.1360871] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
- Raimund Bürger
- Departamento de Ingeniería Matemática, Facultad de Ciencias Físicas y Matemáticas, Centro de Investigación en Ingeniería Matemática, Universidad de Concepción, Concepción, Chile
| | - Julio Careaga
- Departamento de Ingeniería Matemática, Facultad de Ciencias Físicas y Matemáticas, Centro de Investigación en Ingeniería Matemática, Universidad de Concepción, Concepción, Chile
- Centre for Mathematical Sciences, Lund University, Lund, Sweden
| | - Stefan Diehl
- Centre for Mathematical Sciences, Lund University, Lund, Sweden
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5
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Torfs E, Balemans S, Locatelli F, Diehl S, Bürger R, Laurent J, François P, Nopens I. On constitutive functions for hindered settling velocity in 1-D settler models: Selection of appropriate model structure. WATER RESEARCH 2017; 110:38-47. [PMID: 27984804 DOI: 10.1016/j.watres.2016.11.067] [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: 03/18/2016] [Revised: 11/25/2016] [Accepted: 11/30/2016] [Indexed: 06/06/2023]
Abstract
Advanced 1-D models for Secondary Settling Tanks (SSTs) explicitly account for several phenomena that influence the settling process (such as hindered settling and compression settling). For each of these phenomena a valid mathematical expression needs to be selected and its parameters calibrated to obtain a model that can be used for operation and control. This is, however, a challenging task as these phenomena may occur simultaneously. Therefore, the presented work evaluates several available expressions for hindered settling based on long-term batch settling data. Specific attention is paid to the behaviour of these hindered settling functions in the compression region in order to evaluate how the modelling of sludge compression is influenced by the choice of a certain hindered settling function. The analysis shows that the exponential hindered settling forms, which are most commonly used in traditional SST models, not only account for hindered settling but partly lump other phenomena (compression) as well. This makes them unsuitable for advanced 1-D models that explicitly include each phenomenon in a modular way. A power-law function is shown to be more appropriate to describe the hindered settling velocity in advanced 1-D SST models.
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Affiliation(s)
- Elena Torfs
- BIOMATH, Department of Mathematical Modelling, Statistics and Bioinformatics, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000, Ghent, Belgium.
| | - Sophie Balemans
- BIOMATH, Department of Mathematical Modelling, Statistics and Bioinformatics, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000, Ghent, Belgium
| | - Florent Locatelli
- ICube, Département de Mécanique, Université de Strasbourg, 67000, Strasbourg, France
| | - Stefan Diehl
- Centre for Mathematical Sciences, Lund University, P.O. Box 118, S-221 00, Lund, Sweden
| | - Raimund Bürger
- CI(2)MA and Departamento de Ingeniería Matemática, Facultad de Ciencias Físicas y Matemáticas, Universidad de Concepción, Casilla 160-C, Concepción, Chile
| | - Julien Laurent
- ICube, Département de Mécanique, Université de Strasbourg, 67000, Strasbourg, France
| | - Pierre François
- ICube, Département de Mécanique, Université de Strasbourg, 67000, Strasbourg, France
| | - Ingmar Nopens
- BIOMATH, Department of Mathematical Modelling, Statistics and Bioinformatics, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000, Ghent, Belgium.
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Dynamic modelling of solids in a full-scale activated sludge plant preceded by CEPT as a preliminary step for micropollutant removal modelling. Bioprocess Biosyst Eng 2016; 40:499-510. [DOI: 10.1007/s00449-016-1715-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2016] [Accepted: 11/25/2016] [Indexed: 11/25/2022]
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7
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Bürger R, Careaga J, Diehl S, Mejías C, Nopens I, Torfs E, Vanrolleghem PA. Simulations of reactive settling of activated sludge with a reduced biokinetic model. Comput Chem Eng 2016. [DOI: 10.1016/j.compchemeng.2016.04.037] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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8
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Barth A, Bürger R, Kröker I, Rohde C. Computational uncertainty quantification for a clarifier-thickener model with several random perturbations: A hybrid stochastic Galerkin approach. Comput Chem Eng 2016. [DOI: 10.1016/j.compchemeng.2016.02.016] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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9
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Li B, Stenstrom MK. Practical identifiability and uncertainty analysis of the one-dimensional hindered-compression continuous settling model. WATER RESEARCH 2016; 90:235-246. [PMID: 26734783 DOI: 10.1016/j.watres.2015.12.034] [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: 06/23/2015] [Revised: 11/19/2015] [Accepted: 12/19/2015] [Indexed: 06/05/2023]
Abstract
The practical application of the one-dimension hindered-compression settling models remains a challenge, since the model calibration strongly depends on experimental observations with limited information. In this study, the identifiability of parameter subsets of the hindered-compression models is evaluated for various experimental layouts. Global sensitivity analysis is used to preliminarily select the influential parameters which can be reasonably estimated, while the identifiability analysis of parameter subsets is conducted based on the local sensitivity functions and collinearity measures. The batch settling curve observations are informative for calibrating hindered parameters, and to determine the compression parameters, the concentration profile observations may need to be collected. For different experimental layouts, at least three parameters are identifiable, and the number of identifiable parameters can potentially increase to five, if both batch settling curve and concentration observations are available. The parameter subset identifiability is sensitive to the choice of initial parameter values, and determining the initial values of hindered parameters and gel concentration by measuring the hindered settling velocities and the top concentration of the static sediment respectively allows efficient reduction of the sensitivity. Parameter subset estimates are sensitive to the values of fixed parameters, and reliable estimation of identifiable parameter subsets is possible to significantly decrease model prediction uncertainties.
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Affiliation(s)
- Ben Li
- Dept. of Civil and Environmental Engineering, University of California Los Angeles, Los Angeles, CA 90095, USA.
| | - Michael K Stenstrom
- Dept. of Civil and Environmental Engineering, University of California Los Angeles, Los Angeles, CA 90095, USA.
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10
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Guyonvarch E, Ramin E, Kulahci M, Plósz BG. iCFD: Interpreted Computational Fluid Dynamics - Degeneration of CFD to one-dimensional advection-dispersion models using statistical experimental design - The secondary clarifier. WATER RESEARCH 2015; 83:396-411. [PMID: 26248321 DOI: 10.1016/j.watres.2015.06.012] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2014] [Revised: 04/12/2015] [Accepted: 06/08/2015] [Indexed: 06/04/2023]
Abstract
The present study aims at using statistically designed computational fluid dynamics (CFD) simulations as numerical experiments for the identification of one-dimensional (1-D) advection-dispersion models - computationally light tools, used e.g., as sub-models in systems analysis. The objective is to develop a new 1-D framework, referred to as interpreted CFD (iCFD) models, in which statistical meta-models are used to calculate the pseudo-dispersion coefficient (D) as a function of design and flow boundary conditions. The method - presented in a straightforward and transparent way - is illustrated using the example of a circular secondary settling tank (SST). First, the significant design and flow factors are screened out by applying the statistical method of two-level fractional factorial design of experiments. Second, based on the number of significant factors identified through the factor screening study and system understanding, 50 different sets of design and flow conditions are selected using Latin Hypercube Sampling (LHS). The boundary condition sets are imposed on a 2-D axi-symmetrical CFD simulation model of the SST. In the framework, to degenerate the 2-D model structure, CFD model outputs are approximated by the 1-D model through the calibration of three different model structures for D. Correlation equations for the D parameter then are identified as a function of the selected design and flow boundary conditions (meta-models), and their accuracy is evaluated against D values estimated in each numerical experiment. The evaluation and validation of the iCFD model structure is carried out using scenario simulation results obtained with parameters sampled from the corners of the LHS experimental region. For the studied SST, additional iCFD model development was carried out in terms of (i) assessing different density current sub-models; (ii) implementation of a combined flocculation, hindered, transient and compression settling velocity function; and (iii) assessment of modelling the onset of transient and compression settling. Furthermore, the optimal level of model discretization both in 2-D and 1-D was undertaken. Results suggest that the iCFD model developed for the SST through the proposed methodology is able to predict solid distribution with high accuracy - taking a reasonable computational effort - when compared to multi-dimensional numerical experiments, under a wide range of flow and design conditions. iCFD tools could play a crucial role in reliably predicting systems' performance under normal and shock events.
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Affiliation(s)
- Estelle Guyonvarch
- Department of Environmental Engineering, Technical University of Denmark, Miljøvej, Building 113, 2800 Kgs. Lyngby, Denmark
| | - Elham Ramin
- Department of Environmental Engineering, Technical University of Denmark, Miljøvej, Building 113, 2800 Kgs. Lyngby, Denmark
| | - Murat Kulahci
- Department of Applied Mathematics and Computer Science, Technical University of Denmark, Richard Petersens Plads, Building 321, 2800 Kgs. Lyngby, Denmark; Department of Business Administration, Technology and Social Sciences, Luleå University of Technology, SE-97187 Luleå, Sweden
| | - Benedek Gy Plósz
- Department of Environmental Engineering, Technical University of Denmark, Miljøvej, Building 113, 2800 Kgs. Lyngby, Denmark.
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11
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Li B, Stenstrom MK. Construction of analytical solutions and numerical methods comparison of the ideal continuous settling model. Comput Chem Eng 2015. [DOI: 10.1016/j.compchemeng.2015.05.025] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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12
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Locatelli F, François P, Laurent J, Lawniczak F, Dufresne M, Vazquez J, Bekkour K. Detailed Velocity and Concentration Profiles Measurement During Activated Sludge Batch Settling Using an Ultrasonic Transducer. SEP SCI TECHNOL 2015. [DOI: 10.1080/01496395.2014.980002] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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13
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A Detailed Mathematical Modelling Representation of Clean Water Treatment Plants. ACTA ACUST UNITED AC 2015. [DOI: 10.1016/b978-0-444-63576-1.50117-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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14
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Torfs E, Maere T, Bürger R, Diehl S, Nopens I. Impact on sludge inventory and control strategies using the benchmark simulation model no. 1 with the Bürger-Diehl settler model. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2015; 71:1524-1535. [PMID: 26442495 DOI: 10.2166/wst.2015.122] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
An improved one-dimensional (1-D) model for the secondary clarifier, i.e. the Bürger-Diehl model, was recently presented. The decisive difference to traditional layer models is that every detail of the implementation is in accordance with the theory of partial differential equations. The Bürger-Diehl model allows accounting for hindered and compressive settling as well as inlet dispersion. In this contribution, the impact of specific features of the Bürger-Diehl model on settler underflow concentration predictions, plant sludge inventory and mixed liquor suspended solids based control actions are investigated by using the benchmark simulation model no. 1. The numerical results show that the Bürger-Diehl model allows for more realistic predictions of the underflow sludge concentration, which is essential for more accurate wet weather modelling and sludge waste predictions. The choice of secondary settler model clearly has a profound impact on the operation and control of the entire treatment plant and it is recommended to use the Bürger-Diehl model as of now in any wastewater treatment plant modelling effort.
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Affiliation(s)
- E Torfs
- BIOMATH, Department of Mathematical Modelling, Statistics and Bioinformatics, Ghent University, Coupure links 653, B-9000, Ghent, Belgium E-mail:
| | - T Maere
- BIOMATH, Department of Mathematical Modelling, Statistics and Bioinformatics, Ghent University, Coupure links 653, B-9000, Ghent, Belgium E-mail:
| | - R Bürger
- CI²MA and Departamento de Ingeniería Matemática, Facultad de Ciencias Físicas y Matemáticas, Universidad de Concepción, Casilla 160-C, Concepción, Chile
| | - S Diehl
- Centre for Mathematical Sciences, Lund University, P.O. Box 118, S-221 00 Lund, Sweden
| | - I Nopens
- BIOMATH, Department of Mathematical Modelling, Statistics and Bioinformatics, Ghent University, Coupure links 653, B-9000, Ghent, Belgium E-mail:
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15
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Li B, Stenstrom MK. Research advances and challenges in one-dimensional modeling of secondary settling tanks--a critical review. WATER RESEARCH 2014; 65:40-63. [PMID: 25090623 DOI: 10.1016/j.watres.2014.07.007] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2014] [Revised: 07/03/2014] [Accepted: 07/03/2014] [Indexed: 06/03/2023]
Abstract
Sedimentation is one of the most important processes that determine the performance of the activated sludge process (ASP), and secondary settling tanks (SSTs) have been frequently investigated with the mathematical models for design and operation optimization. Nevertheless their performance is often far from satisfactory. The starting point of this paper is a review of the development of settling theory, focusing on batch settling and the development of flux theory, since they played an important role in the early stage of SST investigation. The second part is an explicit review of the established 1-D SST models, including the relevant physical law, various settling behaviors (hindered, transient, and compression settling), the constitutive functions, and their advantages and disadvantages. The third part is a discussion of numerical techniques required to solve the governing equation, which is usually a partial differential equation. Finally, the most important modeling challenges, such as settleability description, settling behavior understanding, are presented.
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Affiliation(s)
- Ben Li
- Dept. of Civil and Environmental Engineering, University of California Los Angeles, 5714 Boelter Hall, Los Angeles, CA 90095, USA.
| | - M K Stenstrom
- Dept. of Civil and Environmental Engineering, University of California Los Angeles, 5714 Boelter Hall, Los Angeles, CA 90095, USA.
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16
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Ramin E, Sin G, Mikkelsen PS, Plósz BG. Significance of settling model structures and parameter subsets in modelling WWTPs under wet-weather flow and filamentous bulking conditions. WATER RESEARCH 2014; 63:209-221. [PMID: 25003213 DOI: 10.1016/j.watres.2014.05.054] [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: 02/12/2014] [Revised: 05/28/2014] [Accepted: 05/29/2014] [Indexed: 06/03/2023]
Abstract
Current research focuses on predicting and mitigating the impacts of high hydraulic loadings on centralized wastewater treatment plants (WWTPs) under wet-weather conditions. The maximum permissible inflow to WWTPs depends not only on the settleability of activated sludge in secondary settling tanks (SSTs) but also on the hydraulic behaviour of SSTs. The present study investigates the impacts of ideal and non-ideal flow (dry and wet weather) and settling (good settling and bulking) boundary conditions on the sensitivity of WWTP model outputs to uncertainties intrinsic to the one-dimensional (1-D) SST model structures and parameters. We identify the critical sources of uncertainty in WWTP models through global sensitivity analysis (GSA) using the Benchmark simulation model No. 1 in combination with first- and second-order 1-D SST models. The results obtained illustrate that the contribution of settling parameters to the total variance of the key WWTP process outputs significantly depends on the influent flow and settling conditions. The magnitude of the impact is found to vary, depending on which type of 1-D SST model is used. Therefore, we identify and recommend potential parameter subsets for WWTP model calibration, and propose optimal choice of 1-D SST models under different flow and settling boundary conditions. Additionally, the hydraulic parameters in the second-order SST model are found significant under dynamic wet-weather flow conditions. These results highlight the importance of developing a more mechanistic based flow-dependent hydraulic sub-model in second-order 1-D SST models in the future.
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Affiliation(s)
- Elham Ramin
- Department of Environmental Engineering (DTU Environment), Technical University of Denmark, Miljøvej, Building 113, DK-2800, Kgs. Lyngby, Denmark.
| | - Gürkan Sin
- CAPEC-Department of Chemical and Biochemical Engineering, Technical University of Denmark, Building 229, DK-2800 Kgs. Lyngby, Denmark.
| | - Peter Steen Mikkelsen
- Department of Environmental Engineering (DTU Environment), Technical University of Denmark, Miljøvej, Building 113, DK-2800, Kgs. Lyngby, Denmark.
| | - Benedek Gy Plósz
- Department of Environmental Engineering (DTU Environment), Technical University of Denmark, Miljøvej, Building 113, DK-2800, Kgs. Lyngby, Denmark.
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