1
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Demiray Z, Akyol NH, Akyol G, Copty NK. Surfactant-enhanced in-situ oxidation of DNAPL source zone: Experiments and numerical modeling. JOURNAL OF CONTAMINANT HYDROLOGY 2023; 258:104233. [PMID: 37625208 DOI: 10.1016/j.jconhyd.2023.104233] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2023] [Revised: 08/09/2023] [Accepted: 08/12/2023] [Indexed: 08/27/2023]
Abstract
In this study we investigate the synergetic effects of combining surfactant-enhanced dissolution with in-situ oxidation of a pool-dominated PCE DNAPL source zone entrapped in porous media. Flow cell flushing experiments packed with silica sand and natural calcareous soil were conducted with a surfactant (Tween 80) and permanganate (MnO4-) used as dissolution and oxidation agents, respectively. The resultant breakthrough curves exhibited a multiple step behavior with mass removal controlled in the latter stages by the less-accessible DNAPL mass. DNAPL spatial architecture, flow-field heterogeneity, and flushing solution all influenced the remediation effort. When taking into account both the surfactant-enhanced dissolution and permanganate oxidation processes, mass-flux reduction/mass-removal behavior relationships indicated that the inclusion of oxidation in the remediation scheme delayed the drop in mass flux from the source zone, leading to improved DNAPL removal efficiency. Numerical modeling was also performed to further evaluate the efficacy of the surfactant-enhanced chemical oxidation of DNAPL PCE with permanganate. The system of reaction equations available in the multiphase flow simulator UTCHEM were adapted to simulate the chemical oxidation process in the presence of a surfactant. The model results yield lower oxidation reaction rate constants in the presence of Tween 80, indicating that Tween 80 can interfere with the reaction rate. However, the increase in the solubility of PCE in the presence of Tween 80 more than compensates for the decrease in reaction rate constant. Overall, for Tween 80/MnO4- applied at sufficient dosages, more efficient DNAPL zone remediation was achieved compared to surfactant flushing or permanganate oxidation alone.
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Affiliation(s)
- Zeynep Demiray
- Institute of Environmental Sciences, Bogazici University, Bebek, 34342 Istanbul, Turkey
| | - Nihat Hakan Akyol
- Department of Geological Engineering, Kocaeli University, 41380 Kocaeli, Turkey
| | - Gokçe Akyol
- Department of Geological Engineering, Kütahya Dumlupınar University, Kütahya, Turkey
| | - Nadim K Copty
- Institute of Environmental Sciences, Bogazici University, Bebek, 34342 Istanbul, Turkey.
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2
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Shojaei MJ, Or D, Shokri N. Localized Delivery of Liquid Fertilizer in Coarse-Textured Soils Using Foam as Carrier. Transp Porous Media 2022. [DOI: 10.1007/s11242-022-01820-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
AbstractAgrochemicals and fertilizers are central to modern agriculture and are credited with the large increase of crop yield as a part of the Green Revolution of the 1960’s. Timely and targeted fertilizer application to crop root zones enhances effectiveness and reduces unintended release to the environment. This is particularly important for highly mobile liquid fertilizers (e.g., nitrate) that can be mobilized with infiltrating water to bypass root-bearing soil volumes. We report a novel liquid fertilizer delivery method using foam as carrier. The high degree of control and mechanical stability of liquid fertilizer foam (defined dispersed gas bubbles in a continuous liquid phase) injection into coarse soils (most susceptible to preferential flows) is proposed a novel delivery method to targeted root zone volumes at concentrations and geometry that promote uptake and reduces losses. This note and preliminary communication meant to serve a proof of concept report comparing foam and conventional liquid fertilizer applications. The results indicate that foam-delivery reduced fertilizer leaching thus improving its retention in soil for similar flow conditions of liquid delivery. Theoretical estimates suggest that the effects of fertilizer retention could be enhanced in more localized (3-D) injection of foam fertilizers and other agrochemicals thus enhancing agronomic efficiency and reducing environmental risk of contamination.
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3
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Bouzid I, Fatin-Rouge N. Assessment of shear-thinning fluids and strategies for enhanced in situ removal of heavy chlorinated compounds-DNAPLs in an anisotropic aquifer. JOURNAL OF HAZARDOUS MATERIALS 2022; 432:128703. [PMID: 35316641 DOI: 10.1016/j.jhazmat.2022.128703] [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: 01/11/2022] [Revised: 02/17/2022] [Accepted: 03/11/2022] [Indexed: 06/14/2023]
Abstract
The removal of chlorinated organic hydrocarbons (COHs) -DNAPLs was studied in permeability-contrasted sandboxes with an egg-box shaped substratum. Aqueous solutions were compared to viscous shear-thinning fluids (xanthan solution and foam). Interfacial and viscous effects were compared by increasing the capillary number of injected fluids. Non-spatially targeted DNAPL recovery (NSTR) where the driving force was the injection pressure, was compared to spatially targeted DNAPL recovery (STR) where a pumping system allowed the controlled flow. A historical contamination made of a complex mixture of COHs and hexachlorobutadiene (HCBD) as a model were used. NSTR results showed that DNAPL recovery with non-viscous liquids did not exceed 40%. The best results were obtained for xanthan solutions with surfactant ~ 1.3 ×CMC for which pure phase recovery amounted to 88% and 93% for HCBD and for the historical DNAPL, respectively. The STR strategy showed similar recovery yields, whereas xanthan concentrations were 10-times lower. Mass balances on DNAPL showed that at most, 0.15% of COHs was dissolved in the aqueous effluents. NZVI (1 g.l-1) were delivered in xanthan in view of the chemical degradation of residual COHs and showed a 65% transmission through the low permeability soil.
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Affiliation(s)
- Iheb Bouzid
- Université de Bourgogne Franche-Comté-Besançon, Institut UTINAM-UMR CNRS 6213, 16, route de Gray, 25030 Besançon, France
| | - Nicolas Fatin-Rouge
- Université de Bourgogne Franche-Comté-Besançon, Institut UTINAM-UMR CNRS 6213, 16, route de Gray, 25030 Besançon, France; Institut de Chimie des Milieux et Matériaux de Poitiers (IC2MP), Université de Poitiers, UMR-CNRS 7285, F-86073 Poitiers, France.
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4
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Vicard A, Atteia O, Bertin H, Lachaud J. Estimation of Local Equilibrium Foam Model Parameters as Functions of the Foam Quality and the Total Superficial Velocity. ACS OMEGA 2022; 7:16866-16876. [PMID: 35647426 PMCID: PMC9134404 DOI: 10.1021/acsomega.1c04899] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Accepted: 04/13/2022] [Indexed: 06/15/2023]
Abstract
In this paper, the behavior of foam in a porous medium is studied in order to understand the effect of the fluid velocity on foam properties. This aspect is crucial during foam injection, as due to radial effects the foam velocity largely decreases around the injection well. The foam properties are detailed through the use of a new local equilibrium foam model parameter estimation approach using an improved new shear function and based on the most widely used STARS model developed by the Computer Modeling Group (CMG). A new mode of calculation of the STARS model parameters is then presented in order to allow both a semiautomated fitting of several quality scan pressure curves and a consideration of the role of the total velocity. The approach is tested through column experiments done at various velocities and gas fractions. Furthermore, the proposed model is also tested on literature results in order to validate it for very different experimental conditions. This study and the fitted results are then used to understand, on both our column experiments and the literature data, the existence of two shear effects and their origins.
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Affiliation(s)
- Alexandre Vicard
- ENSEGID
- EA 4592 Georessources et Environnement, Institut Carnot Isifor, 1 Allee Fernand Daguin, 33607 Pessac, France
- Consortium
innovaSol, https://www.innovasol.org/
| | - Olivier Atteia
- ENSEGID
- EA 4592 Georessources et Environnement, Institut Carnot Isifor, 1 Allee Fernand Daguin, 33607 Pessac, France
- Consortium
innovaSol, https://www.innovasol.org/
| | - Henri Bertin
- I2M,
UMR CNRS 5295, Université de Bordeaux, Esplanade des Arts et Métiers, Talence Cedex 33405, France
| | - Jean Lachaud
- I2M,
UMR CNRS 5295, Université de Bordeaux, Esplanade des Arts et Métiers, Talence Cedex 33405, France
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5
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Davarzani H, Aranda R, Colombano S, Laurent F, Bertin H. Experimental study of foam propagation and stability in highly permeable porous media under lateral water flow: Diverting groundwater for application to soil remediation. JOURNAL OF CONTAMINANT HYDROLOGY 2021; 243:103917. [PMID: 34758436 DOI: 10.1016/j.jconhyd.2021.103917] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Revised: 10/31/2021] [Accepted: 11/01/2021] [Indexed: 06/13/2023]
Abstract
Foam propagation and stability in highly permeable porous media, encountered in soil pollution applications, are still challenging. Here, we investigated the application of foam for blocking the aquifer to divert the flow from a contaminated zone and, therefore, ease the remediation treatments. The main aim was to better understand the critical parameters when the foam is injected into a highly permeable aquifer with high groundwater flow velocity (up to 10 m/day). A decimetric-scale 2D tank experimental setup filled with 1 mm glass beads was used. The front part of the 2D tank was made of transparent glass to photograph the foam flow using the light-reflected method. The water flow was generated horizontally through injection and pumping points on the sides of the tank. The pre-generated foam was injected at the bottom center of the tank. Water streamlines (using dye tracing) and water saturation were investigated using image interpretation. Results show that 100% of the water flow was diverted during the injection of the foam. Foam stability in porous media depends significantly on the horizontal water flow rate. Recirculating water containing the surfactant increases foam stability. The main mechanism of destruction was identified as the dilution of the surfactant in water. However, the head-loss measurements showed that despite foam destruction, the relative permeability of the water phase in the media remained quite low. Injection of foam increases the radius of gas propagation, thanks to foam's high viscosity, compared to a pure gas injection case. These results are new highlights on the efficiency of foam as a blocking agent, showing that it can also serve as a means for gas transport more efficiently in porous media, especially for soil remediation applications.
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Affiliation(s)
| | - Romain Aranda
- BRGM, 3 Avenue Claude Guillemin, 45100 Orléans, France
| | | | - Fabien Laurent
- Solvay RICL, 85 rue des Frères Perret, 69192 St Fons, France
| | - Henri Bertin
- I2M, Université de Bordeaux, 33405 Talence, France
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6
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Abstract
Abstract
In enhanced oil recovery, foam can effectively mitigate conformance problems and maintain a stable displacement front, by trapping gas and reducing its relative permeability in situ. In this study, to understand gas trapping in fractures and how it affects foam behavior, we report foam experiments in a 1-m-long glass model fracture with a hydraulic aperture of 80 $$\upmu $$
μ
m. One wall of the fracture is rough, and the other is smooth. Between the two is a 2D porous medium representing the aperture in a fracture. The fracture model allows direct visualization of foam inside the fracture using a high-speed camera. This study is part of a continuing program to determine how foam behaves as a function of the geometry of the fracture pore space (AlQuaimi and Rossen in Energy & Fuels 33: 68-80, 2018a). We find that local equilibrium of foam (where the rate of bubble generation equals that of bubble destruction) has been achieved within the 1-m model fracture. Foam texture becomes finer, and less gas is trapped as interstitial velocity, and pressure gradient increase. Shear-thinning rheology of foam has also been observed. The fraction of trapped gas is significantly lower in our model (less than 7%) than in 3D geological pore networks. At the extreme, when velocity increases to 7 mm/s, there is no gas trapped inside the fracture. Our experimental results of trapped-gas fraction correlate well with the correlation of AlQuaimi and Rossen (SPE J 23: 788-802, 2018b) for fracture-like porous media. This suggests that the correlation can also be applied to gas trapping in fractures with other geometries.
Article Highlights
We have made a lab-scale 1-meter-long transparent glass model representing a geological fracture with roughened surface, and we have implemented a direct method of image analysis to quantify the texture of bubbles in the fracture and to link the texture with the strength of the foam;
We have successfully created surfactant-stabilized foam flow inside the fracture and examined its stability along the 1-meter-long fracture;
We explain the mechanism of gas trapping in fractures and how it affects foam behavior. We also discuss how viscous force and capillary force affect gas trapping in fractures at our experimental conditions.
Graphic Abstract
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7
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Forey N, Atteia O, Omari A, Bertin H. Use of saponin foam reinforced with colloidal particles as an application to soil remediation: Experiments in a 2D tank. JOURNAL OF CONTAMINANT HYDROLOGY 2021; 238:103761. [PMID: 33482372 DOI: 10.1016/j.jconhyd.2020.103761] [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: 07/27/2020] [Revised: 12/24/2020] [Accepted: 12/26/2020] [Indexed: 06/12/2023]
Abstract
Foam can be used to achieve environmental remediation in case of contamination caused by light non aqueous phase spills. However, when it comes in contact with oily pollutants, foam becomes weaker and its life time is greatly reduced. Such weakening can be dampened by using silica particles -together with saponin surfactant- which were shown to reinforce foam in bulk and 1D sandpack experiments. Here is addressed both foam propagation in a 2D porous media when buoyancy and gravity interfere, and foam behaviour when in contact with floating oil. Therefore, macroscopic foam displacement, and specific liquid and gas phases behaviours were studied in a 2D-tank. A piston-like displacement was observed during foam propagation in the absence of oil, while foam liquid phase was influenced by gravity and did not propagate homogeneously on entire tank height. In the presence of oil, foam was partly destroyed, which increased the local permeability of gas and created new preferential paths for gas flow. This effect was partially avoided via a surfactant concentration increase, but solid colloidal particles turned out to be a more efficient stabilizing agent, by significantly increasing foam strength and its oil-tolerance.
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Affiliation(s)
- Natacha Forey
- I2M, UMR CNRS 5295, Université de Bordeaux, Esplanade des Arts et Métiers, 33405 Talence Cedex, France.
| | - Olivier Atteia
- ENSEGID, EA 4592, 1 Allée Fernand Daguin, 33607 Pessac, France
| | - Abdelaziz Omari
- I2M, UMR CNRS 5295, Université de Bordeaux, Esplanade des Arts et Métiers, 33405 Talence Cedex, France
| | - Henri Bertin
- I2M, UMR CNRS 5295, Université de Bordeaux, Esplanade des Arts et Métiers, 33405 Talence Cedex, France
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8
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Bouzid I, Pino Herrera D, Dierick M, Pechaud Y, Langlois V, Klein PY, Albaric J, Fatin-Rouge N. A new foam-based method for the (bio)degradation of hydrocarbons in contaminated vadose zone. JOURNAL OF HAZARDOUS MATERIALS 2021; 401:123420. [PMID: 32763708 DOI: 10.1016/j.jhazmat.2020.123420] [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: 03/03/2020] [Revised: 07/02/2020] [Accepted: 07/04/2020] [Indexed: 06/11/2023]
Abstract
An innovative foam-based method for Fenton reagents (FR) and bacteria delivery was assessed for the in situ remediation of a petroleum hydrocarbon-contaminated unsaturated zone. The surfactant foam was first injected, then reagent solutions were delivered and propagated through the network of foam lamellae with a piston-like effect. Bench-scale experiments demonstrated the feasibility of the various treatments with hydrocarbon (HC) removal efficiencies as high as 96 %. Compared to the direct injection of FR solutions, the foam-based method led to larger radii of influence and more isotropic reagents delivery, whereas it did not show any detrimental effect regarding HC oxidation. Despite 25 % of HCs were expelled from the treated zone because of high foam viscosity, average degradation rates were increased by 20 %. At field-scale, foam and reagent solutions injections in soil were tracked both using visual observation and differential electric resistivity tomography. The latter demonstrated the controlled delivery of the reactive solutions using the foam-based method. Even if the foam-based method duration is about 5-times longer than the direct injection of amendment solutions, it provides important benefits, such as the confinement of harmful volatile hydrocarbons during Fenton treatments, the enhanced reagents delivery and the 30 % lower consumption of the latter.
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Affiliation(s)
- I Bouzid
- Université de Bourgogne Franche-Comté-Besançon, Institut UTINAM-UMR CNRS 6213, 16, route de Gray, 25030, Besançon, France
| | - D Pino Herrera
- Université Paris-Est, Laboratoire Géomatériaux et Environnement (LGE), EA4508, UPEM, 77454, Marne-la-Vallée, France
| | - M Dierick
- REMEA, 22 Rue Lavoisier, 92000 Nanterre, France
| | - Y Pechaud
- Université Paris-Est, Laboratoire Géomatériaux et Environnement (LGE), EA4508, UPEM, 77454, Marne-la-Vallée, France
| | - V Langlois
- Université Paris-Est, Laboratoire Géomatériaux et Environnement (LGE), EA4508, UPEM, 77454, Marne-la-Vallée, France
| | - P Y Klein
- REMEA, 22 Rue Lavoisier, 92000 Nanterre, France
| | - J Albaric
- Laboratoire de Chrono-Environnement, UMR CNRS 6249, Université de Bourgogne, Franche-Comté, France
| | - N Fatin-Rouge
- Université de Bourgogne Franche-Comté-Besançon, Institut UTINAM-UMR CNRS 6213, 16, route de Gray, 25030, Besançon, France.
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9
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Ji W, Parameswarappa Jayalakshmamma M, Abou Khalil C, Zhao L, Boufadel M. Removal of hydrocarbon from soils possessing macro-heterogeneities using electrokinetics and surfactants. CHEMICAL ENGINEERING JOURNAL ADVANCES 2020. [DOI: 10.1016/j.ceja.2020.100030] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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10
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Aranda R, Davarzani H, Colombano S, Laurent F, Bertin H. Experimental Study of Foam Flow in Highly Permeable Porous Media for Soil Remediation. Transp Porous Media 2020. [DOI: 10.1007/s11242-020-01443-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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11
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Forey N, Atteia O, Omari A, Bertin H. Saponin foam for soil remediation: On the use of polymer or solid particles to enhance foam resistance against oil. JOURNAL OF CONTAMINANT HYDROLOGY 2020; 228:103560. [PMID: 31699303 DOI: 10.1016/j.jconhyd.2019.103560] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Revised: 09/27/2019] [Accepted: 10/10/2019] [Indexed: 06/10/2023]
Abstract
Foams can be used to remediate aquifer pollution due to industrial leaks. However, when in contact with oily pollutants, foams may collapse and thus have a very limited life-time. A suitable formulation of biodegradable foam that resists oil contact is therefore needed. Hence, the ability of xanthan polymer and silica colloidal particles to stabilise foam against oil was investigated. Their performance in terms of stabilisation was evaluated via foam generation experiments in columns of porous medium, conducted with and without oil. The results show that the addition of xanthan polymer led to an increase in the viscosity of the solution, which thwarted the formation of foam. It did not improve the resistance of foam to oil, but increased altogether the resistance factor up to more than twice the original value. Concerning silica particles, it was demonstrated that they both noticeably increased resistance factor and moderately stabilised foam against oil by 20% at optimum concentration. As such, this study presents a new way to reinforce foam against oil for soil remediation issues.
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Affiliation(s)
- Natacha Forey
- I2M, UMR CNRS 5295, Université de Bordeaux, Esplanade des Arts et Métiers, Talence Cedex 33405, France.
| | - Olivier Atteia
- ENSEGID, EA 4592, 1 Allée Fernand Daguin, Pessac 33607, France
| | - Abdelaziz Omari
- I2M, UMR CNRS 5295, Université de Bordeaux, Esplanade des Arts et Métiers, Talence Cedex 33405, France
| | - Henri Bertin
- I2M, UMR CNRS 5295, Université de Bordeaux, Esplanade des Arts et Métiers, Talence Cedex 33405, France
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12
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Ramezanzadeh M, Khasi S, Fatemi M, Ghazanfari MH. Remediation of trapped DNAPL enhanced by SDS surfactant and silica nanoparticles in heterogeneous porous media: experimental data and empirical models. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2020; 27:2658-2669. [PMID: 31836978 DOI: 10.1007/s11356-019-07194-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2019] [Accepted: 11/27/2019] [Indexed: 06/10/2023]
Abstract
The remediation of nonaqueous phase liquids (NAPLs) enhanced by surfactant and nanoparticles (NP) has been investigated in numerous studies. However, the role of NP-assisted surfactants in the dissolution process is still not well discussed. Besides, there is a lack of empirical dissolution models considering the effects of initial residual saturation Strap, NAPL distribution, and surfactant concentration in NAPL-aqueous phase systems. In this work, micromodel experiments are conducted to quantify mass transfer coefficients for different injected aqueous phases including deionized water, SDS surfactant solutions, and NP-assisted solutions with different levels of concentrations and flow rates. Observations reveal that silica nanoparticles (SNP) can significantly enhance interphase mass transfer, while SDS surfactant reduces the mass transfer coefficient. In addition, Strap and intrinsic interfacial area ai, as an indicator of dense nonaqueous phase liquids (DNAPL) distribution, influence the interphase mass transfer. The ai is also independent of DNAPL saturation SNAPL except for SNAPL < 7% when ganglia breakup occurs. Based on these observations, new empirical dissolution models are proposed in the presence and the absence of SDS surfactant and SNP in which ai, Strap, and surfactant concentrations are introduced as new parameters. The evaluated mass transfer rate coefficients using the proposed models show a significant improvement compared to available empirical models. The finding of this study might be attractive for application in field-scale simulations of surfactant-enhanced aquifer remediation (SEAR) and NP-assisted methods.
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Affiliation(s)
- Mehdi Ramezanzadeh
- Chemical and Petroleum Engineering Department, Sharif University of Technology, Azadi Ave, Tehran, Iran
| | - Saeid Khasi
- Chemical and Petroleum Engineering Department, Sharif University of Technology, Azadi Ave, Tehran, Iran
| | - Mobeen Fatemi
- Chemical and Petroleum Engineering Department, Sharif University of Technology, Azadi Ave, Tehran, Iran
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13
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Abstract
Abstract
Foam can improve sweep efficiency in gas-injection-enhanced oil recovery. Surfactant-alternating-gas (SAG) is a favored method of foam injection. Laboratory data indicate that foam can be non-Newtonian at low water fractional flow fw, and therefore during gas injection in a SAG process. We investigate the implications of this finding for mobility control and injectivity, by extending fractional-flow theory to gas injection in a non-Newtonian SAG process in radial flow. We make most of the standard assumptions of fractional-flow theory (incompressible phases, one-dimensional displacement through a homogeneous reservoir, instantaneous attainment of local equilibrium), excluding Newtonian mobilities. For this initial study, we ignore the effect of changing or non-uniform oil saturation on foam. Non-Newtonian behavior at low fw implies that the limiting water saturation for foam stability varies as superficial velocity decreases with radial distance from the well. We discretize the domain radially and perform Buckley–Leverett analysis on each narrow increment in radius. Solution characteristics move outward with fixed fw. We base the foam model parameters and non-Newtonian behavior on laboratory data in the absence of oil. We compare results to mobility and injectivity determined by conventional simulation, where grid resolution is usually limited. For shear-thinning foam, mobility control improves as the foam front propagates from the well, but injectivity declines somewhat with time. This change in mobility ratio is not that at steady state at fixed water fractional flow in the laboratory, however, because the shock front in a non-Newtonian SAG process does not propagate at fixed fractional flow (though individual characteristics do). Moreover, the shock front is not governed by the conventional condition of tangency to the fractional-flow curve, though it continually approaches this condition. Injectivity benefits from the increased mobility of shear-thinning foam near the well. The foam front, which maintains a constant dimensionless velocity for Newtonian foam, decelerates somewhat with time for shear-thinning foam. For shear-thickening foam, mobility control deteriorates as the foam front advances, though injectivity improves somewhat with time. Overall, however, injectivity suffers from reduced foam mobility at high superficial velocity near the well. The foam front accelerates somewhat with time. Conventional simulators cannot adequately represent these effects, or estimate injectivity accurately, in the absence of extraordinarily fine grid resolution near the injection well.
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14
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Bouzid I, Maire J, Fatin-Rouge N. Comparative assessment of a foam-based oxidative treatment of hydrocarbon-contaminated unsaturated and anisotropic soils. CHEMOSPHERE 2019; 233:667-676. [PMID: 31195271 DOI: 10.1016/j.chemosphere.2019.05.295] [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: 03/27/2019] [Revised: 05/28/2019] [Accepted: 05/31/2019] [Indexed: 06/09/2023]
Abstract
In situ delivery of liquid reagents in vadose zone is limited by soil anisotropy and gravity. The enhanced delivery of persulfate (PS) as oxidant, using a new foam-based method (F-PS) was compared at bench-scale to traditional water-based (W-PS) and surfactant solution-based (S-PS) deliveries. The goal was to distribute PS uniformly in coal tar-contaminated unsaturated and anisotropic soils, both in terms of permeability and contamination. Water was the less efficiently delivered fluid because of the hydrophobicity of the contaminated soils. Surfactant enhanced PS-distribution into contaminated zones by reducing interfacial tension and inverting soil wettability. Regardless of coal tar contamination contrasts (0 vs. 5 and 1 vs. 10 g kg soil-1) or strong permeability contrasts, PS-solution injection after foam injection led to the most uniform reagents delivery. While PS-concentration varied more than 5-times between zones using W-PS and S-PS methods, it varied less than 1.6-times when the F-PS one was used. Finally, despite unfavorable conditions, the foam-based method did not show any detrimental effect regarding the oxidation of hydrocarbons compared to the W-PS and S-PS methods carried out in ideal conditions. Moreover, hydrocarbon degradation rates were slightly higher when using F-PS than S-PS due to a lower surfactant content in the targeted zone.
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Affiliation(s)
- Iheb Bouzid
- Université de Bourgogne Franche-Comté - Besançon, Institut UTINAM - UMR CNRS 6213, 16, Route de Gray, 25030, Besançon, France
| | - Julien Maire
- Université de Bourgogne Franche-Comté - Besançon, Institut UTINAM - UMR CNRS 6213, 16, Route de Gray, 25030, Besançon, France
| | - Nicolas Fatin-Rouge
- Université de Bourgogne Franche-Comté - Besançon, Institut UTINAM - UMR CNRS 6213, 16, Route de Gray, 25030, Besançon, France.
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15
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Maire J, Davarzani H, Colombano S, Fatin-Rouge N. Targeted delivery of hydrogen for the bioremediation of aquifers contaminated by dissolved chlorinated compounds. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2019; 249:443-452. [PMID: 30913443 DOI: 10.1016/j.envpol.2019.03.033] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2018] [Revised: 02/27/2019] [Accepted: 03/10/2019] [Indexed: 06/09/2023]
Abstract
Dihydrogen (H2) gas injection is a promising option to enhance the reductive biodehalogenation of contaminants in groundwater. However, it is challenging to ensure its targeted delivery at the right places in plumes, and for the long times required for bioremediation. In this paper, the ability of surfactant foam to retain H2 in the saturated zone and to enhance its release in the dissolved form was compared to traditional biosparging. H2 gas was injected, either alone, or as foam, in a 2D saturated cell packed with glass beads. This cell was continuously flushed with deoxygenated water to mimic aquifer circulation, and H2 was studied both in terms of gas distribution in the cell and dissolved concentrations downstream the injection zone. Experimental results are discussed in conjunction with simulations obtained using modeling. Both show that the viscous behavior of foam allows to efficiently retain greater volumes of H2 gas, 3.5 times higher than biosparging. Moreover, it is retained in a dense manner around the injection point, making possible the targeted delivery of this reagent. Besides, the gas dissolution in groundwater showed to be steadier and more persistent when gas was injected as foam, with dissolution rate constants observed to be 1.12 à 1.58 times lower. Finally, the retained foamed-gas persistently reduced water's relative permeability 1.7 to 5 times, diverting the groundwater flow from the treated zone despite the fast elution of the surfactant. Hence, when H2-foam injection is targeted to plume's contaminant concentration hotspots, on top of enhancing bioremediation, it can reduce contaminant diffusion to groundwater.
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Affiliation(s)
- Julien Maire
- Institut UTINAM, Université de Bourgogne Franche-Comté, 16 Route de Gray, 25000, Besançon, France
| | | | | | - Nicolas Fatin-Rouge
- Institut UTINAM, Université de Bourgogne Franche-Comté, 16 Route de Gray, 25000, Besançon, France.
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Tracking a Foam Front in a 3D, Heterogeneous Porous Medium. Transp Porous Media 2018. [DOI: 10.1007/s11242-018-1185-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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17
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Shi L, Chen J, Wang Q, Song X. Effects of carrier on the transport and DDT removal performance of nano-zerovalent iron in packed sands. CHEMOSPHERE 2018; 209:489-495. [PMID: 29940532 DOI: 10.1016/j.chemosphere.2018.06.123] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2017] [Revised: 06/15/2018] [Accepted: 06/18/2018] [Indexed: 06/08/2023]
Abstract
The delivery of nano-zerovalent iron (nZVI) as a remediation agent to targeted areas in soil was studied using different carriers. Among water, surfactant solution, and surfactant foam, the nZVI transport and carrying abilities followed the order of surfactant foam > surfactant solution > water. The nZVI migration was also facilitated by increased soil particle size and high surfactant concentration. Batch experiments probed the remediation of dichlorodiphenyltrichloroethane (DDT)-contaminated sand under different conditions. Compared to surfactant solution, the use of foam as a carrier achieved much higher DDT removal efficiencies for both coarse (foam/solution: 99/69%) and fine (foam/solution: 60/26%) sands. Additionally, the DDT removal efficiency was strongly influenced by surfactant concentration: foams generated using 1 and 5 g L-1 sodium lauryl ether sulfate (SLES) solutions reached the respective efficiencies of 44% and 75% under identical experimental conditions. However, the nature of the surfactant did not significantly affect the total removal efficiency of DDT. Solubilization, increased sweep efficiency, and reduction by nZVI were identified as factors affecting the DDT removal efficiency, and all three of them were involved when foam-nZVI was used as the flushing fluid.
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Affiliation(s)
- Lanxiang Shi
- Key Laboratory for Water and Sediment Sciences of the Ministry of Education, School of Environment, Beijing Normal University, 19 Xinjiekouwai Street, Haidian District, Beijing, 100875, China
| | - Jiajun Chen
- Key Laboratory for Water and Sediment Sciences of the Ministry of Education, School of Environment, Beijing Normal University, 19 Xinjiekouwai Street, Haidian District, Beijing, 100875, China.
| | - Qingwei Wang
- Key Laboratory for Water and Sediment Sciences of the Ministry of Education, School of Environment, Beijing Normal University, 19 Xinjiekouwai Street, Haidian District, Beijing, 100875, China
| | - Xinran Song
- Key Laboratory for Water and Sediment Sciences of the Ministry of Education, School of Environment, Beijing Normal University, 19 Xinjiekouwai Street, Haidian District, Beijing, 100875, China
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