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Cabrera V, López-Vizcaíno R, Yustres Á, Navarro V. Reactive transport model for bentonites in COMSOL multiphysics: Benchmark and validation exercise. Chemosphere 2024; 350:141050. [PMID: 38154672 DOI: 10.1016/j.chemosphere.2023.141050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/11/2023] [Revised: 12/18/2023] [Accepted: 12/26/2023] [Indexed: 12/30/2023]
Abstract
At present, the deep geological repository concept for spent nuclear fuel is considered the most reliable and safe technique for the permanent disposal of this type of waste. One of the many safety elements used is an engineered barrier made of compacted bentonite. This material allows the encapsulated waste to be isolated from the host rock. Therefore, there is great interest in a detailed study of the behavior of bentonites to different changes in the composition of the surrounding groundwater. In this context, this work presents a new reactive transport model for bentonites implemented in the COMSOL Multiphysics platform. The model contemplates a non-simplistic geochemical system composed of 42 species and 4 minerals. Reactive transport involves the diffusive-dispersive-advective processes defined by the Nernst Planck equations for two overlapping modeling levels (macro- and microstructural) to simulate the behavior of double-porosity media. The uniqueness of this model is that the system of equations used to calculate the chemical speciation problem and the advective-diffusive-dispersive transport can be integrally solved in COMSOL. The model has been satisfactorily verified and validated using the benchmark exercise consisting of the simulation of the multicomponent advective-diffusive column experiment conducted on a compacted bentonite core extracted from a field experiment (LOT project) in the Äspö Hardrock laboratory (Sweden).
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Affiliation(s)
- Virginia Cabrera
- Geoenvironmental Group, Department of Civil Engineering and Construction, Civil Engineering School, University of Castilla-La Mancha, Ciudad Real, Spain
| | - Rubén López-Vizcaíno
- Geoenvironmental Group, Department of Civil Engineering and Construction, Civil Engineering School, University of Castilla-La Mancha, Ciudad Real, Spain.
| | - Ángel Yustres
- Geoenvironmental Group, Department of Civil Engineering and Construction, Civil Engineering School, University of Castilla-La Mancha, Ciudad Real, Spain.
| | - Vicente Navarro
- Geoenvironmental Group, Department of Civil Engineering and Construction, Civil Engineering School, University of Castilla-La Mancha, Ciudad Real, Spain
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López-Vizcaíno R, Cabrera V, Sprocati R, Muniruzzaman M, Rolle M, Navarro V, Yustres Á. A modeling approach for electrokinetic transport in double-porosity media. Electrochim Acta 2022. [DOI: 10.1016/j.electacta.2022.141139] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Miller de Melo Henrique J, Isidro J, Sáez C, López-Vizcaíno R, Yustres A, Navarro V, Dos Santos EV, Rodrigo MA. Enhancing soil vapor extraction with EKSF for the removal of HCHs. Chemosphere 2022; 296:134052. [PMID: 35189200 DOI: 10.1016/j.chemosphere.2022.134052] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Revised: 02/14/2022] [Accepted: 02/16/2022] [Indexed: 06/14/2023]
Abstract
This paper evaluates the combination of electrokinetic soil flushing (EKSF) with soil vapor extraction (SVE) for the removal of four hexachlorocyclohexane (HCH) isomers contained in a real matrix. Results demonstrate that the combination of EKSF and SVE can be positive, but it is required the application of high electric fields (3 V cm-1) in order to promote a higher temperature in the system, which improves the volatilization of the HCH contained in the system. Electrokinetic transport is also enhanced with the application of higher electric gradients, but these transport processes are slower than the volatilization processes, which are the primary in this system. Hence collection of species in the electrolyte wells is negligible as compared to the compound dragged with air by the SVE but the temperature increase demonstrates a good performance. Combination of EKSF with SVE can efficiently exhaust the four HCH isomers reaching a removal of more than 90% after 15 days of treatment (20% more than values attained by SVE) but it is required the application of high electric fields to promote a higher temperature in the system (to improve the volatilization) and EK transport (to improve the dragging). 1-D transport model can be easily used to estimate the average pore water velocity and the effective diffusion of each compound under the different experimental conditions tested.
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Affiliation(s)
- João Miller de Melo Henrique
- Postgraduate Program in Chemical Engineering, School of Science and Technology, Federal University of Rio Grande do Norte, 59078-970, Natal, RN, Brazil; Department of Chemical Engineering, Faculty of Chemical Sciences & Technologies, Universidad de Castilla La Mancha, Campus Universitario, s/n, 13071, Ciudad Real, Spain
| | - Julia Isidro
- Department of Chemical Engineering, Faculty of Chemical Sciences & Technologies, Universidad de Castilla La Mancha, Campus Universitario, s/n, 13071, Ciudad Real, Spain
| | - Cristina Sáez
- Department of Chemical Engineering, Faculty of Chemical Sciences & Technologies, Universidad de Castilla La Mancha, Campus Universitario, s/n, 13071, Ciudad Real, Spain
| | - Rubén López-Vizcaíno
- Geoenvironmental Group, Civil Engineering School, University of Castilla-La Mancha, Avda. Camilo José Cela s/n, 13071, Ciudad Real, Spain
| | - Angel Yustres
- Geoenvironmental Group, Civil Engineering School, University of Castilla-La Mancha, Avda. Camilo José Cela s/n, 13071, Ciudad Real, Spain
| | - Vicente Navarro
- Geoenvironmental Group, Civil Engineering School, University of Castilla-La Mancha, Avda. Camilo José Cela s/n, 13071, Ciudad Real, Spain
| | - Elisama V Dos Santos
- Postgraduate Program in Chemical Engineering, School of Science and Technology, Federal University of Rio Grande do Norte, 59078-970, Natal, RN, Brazil
| | - Manuel A Rodrigo
- Department of Chemical Engineering, Faculty of Chemical Sciences & Technologies, Universidad de Castilla La Mancha, Campus Universitario, s/n, 13071, Ciudad Real, Spain.
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Maldonado S, López-Vizcaíno R, Rodrigo MA, Cañizares P, Navarro V, Roa G, Barrera C, Sáez C. Scale-up of electrokinetic permeable reactive barriers for the removal of organochlorine herbicide from spiked soils. J Hazard Mater 2021; 417:126078. [PMID: 33992923 DOI: 10.1016/j.jhazmat.2021.126078] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2021] [Revised: 03/30/2021] [Accepted: 05/05/2021] [Indexed: 06/12/2023]
Abstract
This work aims to shed light on the scale-up a combined electrokinetic soil flushing process (EKSF) with permeable reactive barriers (PRB) for the treatment of soil spiked with clopyralid. To do this, remediation tests at lab (3.45 L), bench (175 L) and pilot (1400 L) scales have been carried out. The PRB selected was made of soil merged with particles of zero valent iron (ZVI) and granular activated carbon (GAC). Results show that PRB-EKSF involved electrokinetic transport and dehalogenation as the main mechanisms, while adsorption on GAC was not as relevant as initially expected. Clopyralid was not detected in the electrolyte wells and only in the pilot scale, significant amounts of clopyralid remained in the soil after 600 h of operation. Picolinic acid was the main dehalogenated product detected in the soil after treatment and mobilized by electro-osmosis, mostly to the cathodic well. The transport of volatile compounds into the atmosphere was promoted at pilot scale because of the larger soil surface exposed to the atmosphere and the electrical heating caused by ohmic losses and the larger interelectrode gap.
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Affiliation(s)
- S Maldonado
- Department of Environmental Chemistry, College of Chemistry, Autonomous University of the State of Mexico, 50120 Toluca de Lerdo, Mexico
| | - R López-Vizcaíno
- Geo-Environmental Group, Universidad de Castilla-La Mancha, Avda. Camilo José Cela s/n, Ciudad Real 13071, Spain
| | - M A Rodrigo
- Department of Chemical Engineering, College of Chemical Sciences and Technologies, University of Castilla-La Mancha, Campus Universitario s/n, 13071 Ciudad Real, Spain
| | - P Cañizares
- Department of Chemical Engineering, College of Chemical Sciences and Technologies, University of Castilla-La Mancha, Campus Universitario s/n, 13071 Ciudad Real, Spain
| | - V Navarro
- Geo-Environmental Group, Universidad de Castilla-La Mancha, Avda. Camilo José Cela s/n, Ciudad Real 13071, Spain
| | - G Roa
- Department of Environmental Chemistry, College of Chemistry, Autonomous University of the State of Mexico, 50120 Toluca de Lerdo, Mexico
| | - C Barrera
- Department of Environmental Chemistry, College of Chemistry, Autonomous University of the State of Mexico, 50120 Toluca de Lerdo, Mexico
| | - C Sáez
- Department of Chemical Engineering, College of Chemical Sciences and Technologies, University of Castilla-La Mancha, Campus Universitario s/n, 13071 Ciudad Real, Spain.
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López-Vizcaíno R, Yustres Á, Cabrera V, Navarro V. A worksheet-based tool to implement reactive transport models in COMSOL Multiphysics. Chemosphere 2021; 266:129176. [PMID: 33316469 DOI: 10.1016/j.chemosphere.2020.129176] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Revised: 11/11/2020] [Accepted: 11/29/2020] [Indexed: 06/12/2023]
Abstract
The increasing needs for modelling of reactive transport phenomena in different areas of environmental modelling have led to the development of many numerical codes. However, many of them suffer from a lack of flexibility, which hinders the adaptation of the codes to new problems. Moreover, in many cases, changes can be done by a very reduced group of people, and often by a single person, the main developer. Implementation platforms based on multiphysics modelling removes these barriers, although until now within that programming environments has been only possible the coupling of geochemical codes to transport equations using operator splitting techniques. This paper presents the EE4MGM tool, a MS Excel worksheet, provided in supplementary material, for the edition and complete implementation of reactive transport models in COMSOL. The tool automatically generates the code needed to solve the desired reactive transport problem by selecting only which species make up the geochemical system. This way, the numerical model will be completely adapted to the idealisation to be applied, being able to choose easily and effortlessly from a wide range of different levels of conceptual complexity. The organization of data input and the equation libraries obtained for the implementation in the multiphysics COMSOL environment are first described. Afterwards, two examples, in one and two-dimensional domains, to check the utility of the tool are presented.
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Affiliation(s)
- Rubén López-Vizcaíno
- Geoenvironmental Group, Civil Engineering School, University of Castilla-La Mancha, Avda. Camilo José Cela s/n, 13071, Ciudad Real, Spain
| | - Ángel Yustres
- Geoenvironmental Group, Civil Engineering School, University of Castilla-La Mancha, Avda. Camilo José Cela s/n, 13071, Ciudad Real, Spain.
| | - Virginia Cabrera
- Geoenvironmental Group, Civil Engineering School, University of Castilla-La Mancha, Avda. Camilo José Cela s/n, 13071, Ciudad Real, Spain
| | - Vicente Navarro
- Geoenvironmental Group, Civil Engineering School, University of Castilla-La Mancha, Avda. Camilo José Cela s/n, 13071, Ciudad Real, Spain
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Yustres Á, López-Vizcaíno R, Cabrera V, Rodrigo MA, Navarro V. Donnan-ion hydration model to estimate the electroosmotic permeability of clays. Electrochim Acta 2020. [DOI: 10.1016/j.electacta.2020.136758] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Paixão IC, López-Vizcaíno R, Solano AMS, Martínez-Huitle CA, Navarro V, Rodrigo MA, Dos Santos EV. Electrokinetic-Fenton for the remediation low hydraulic conductivity soil contaminated with petroleum. Chemosphere 2020; 248:126029. [PMID: 32035385 DOI: 10.1016/j.chemosphere.2020.126029] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2019] [Revised: 01/19/2020] [Accepted: 01/23/2020] [Indexed: 05/25/2023]
Abstract
The use of electrokinetic Fenton (EK Fenton) process, as promising soil remediation approach, was investigated by using an iron electrode with different supporting electrolytes (tap water, H2O2, and citric acid) to depollute soil spiked with petroleum where kaolin was selected as low hydraulic conductivity. The results clearly confirm that, the combination of electrokinetic remediation (EK) and Fenton technologies, is an efficient oxidizing approach for removing hydrocarbons from this kind of soil. In fact, the electrokinetic Fenton reactions and the control of the soil pH conditions by adding citric acid enhanced the oxidation process because the addition of the H2O2 with iron electrode resulted in higher removal efficiencies (89%) for total petroleum hydrocarbons (TPHs). These figures allowed to confirm that EK Fenton process with pH control contributed for the transport of H2O2 and Fe2+ ions in the soil by electromigration and eletro-osmotic phenomena. Conversely, no control of pH conditions when only EK was applied, achieved lower hydrocarbons removal (27%) after 15 d of treatment due to the precipitation of iron ions. Finally, the efficiency of the EK Fenton remediation prevented the generation of secondary effluent with higher organic content, avoiding its treatment by other advanced oxidation process.
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Affiliation(s)
- I C Paixão
- School of Science and Technology, Federal University of Rio Grande do Norte, Campus Universitario, 59078-970, Natal, Brazil
| | - R López-Vizcaíno
- School of Science and Technology, Federal University of Rio Grande do Norte, Campus Universitario, 59078-970, Natal, Brazil; Institute of Chemistry, Federal University of Rio Grande do Norte, Campus Universitario, 59078-970, Natal, Brazil; Geoenvironmental Group, Civil Engineering School, University of Castilla-La Mancha, Avda. Camilo José Cela S/n, 13071, Ciudad Real, Spain
| | - A M S Solano
- Institute of Chemistry, Federal University of Rio Grande do Norte, Campus Universitario, 59078-970, Natal, Brazil
| | - C A Martínez-Huitle
- Institute of Chemistry, Federal University of Rio Grande do Norte, Campus Universitario, 59078-970, Natal, Brazil
| | - V Navarro
- Geoenvironmental Group, Civil Engineering School, University of Castilla-La Mancha, Avda. Camilo José Cela S/n, 13071, Ciudad Real, Spain
| | - M A Rodrigo
- Chemical Engineering Department, University of Castilla-La Mancha, E. Costa Novella Buiding, Campus Universitario S/n, 13071, Ciudad Real, Spain
| | - E V Dos Santos
- School of Science and Technology, Federal University of Rio Grande do Norte, Campus Universitario, 59078-970, Natal, Brazil.
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López-Vizcaíno R, dos Santos E, Yustres A, Rodrigo M, Navarro V, Martínez-Huitle C. Calcite buffer effects in electrokinetic remediation of clopyralid-polluted soils. Sep Purif Technol 2019. [DOI: 10.1016/j.seppur.2018.11.034] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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9
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López-Vizcaíno R, Yustres A, Sáez C, Cañizares P, Asensio L, Navarro V, Rodrigo MA. Techno-economic analysis of the scale-up process of electrochemically-assisted soil remediation. J Environ Manage 2019; 231:570-575. [PMID: 30388654 DOI: 10.1016/j.jenvman.2018.10.084] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2018] [Revised: 10/16/2018] [Accepted: 10/23/2018] [Indexed: 06/08/2023]
Abstract
This work presents a techno-economic study of the scaling-up of the electrochemically-assisted soil remediation (EASR) process of polluted soil. Four scales have been selected for the study: laboratory, bench, pilot and prototype, with a capacity of treating a volume of soil of 1 × 10-4, 2 × 10-3, 0.11 and 21.76 m3, respectively. This study analyses the technical information produced by studies carried out at each scale, and informs about the fixed costs (construction of the electrokinetic remediation reactor, installation of auxiliary services and purchase of analytical equipment) and variable costs (start-up, operation and dismantling of the test) derived from running a test at each of the evaluated scales. The information discussed in based on the experience gained with many evaluations carried out over the last decade at these scales. This information can provide useful guidance for developing a scaling-up of the EASR for many researchers starting on the evaluation of this important environmental remediation technology.
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Affiliation(s)
- R López-Vizcaíno
- Geoenvironmental Group, Civil Engineering School, University of Castilla-La Mancha, Avda. Camilo José Cela s/n, 13071 Ciudad Real, Spain.
| | - A Yustres
- Geoenvironmental Group, Civil Engineering School, University of Castilla-La Mancha, Avda. Camilo José Cela s/n, 13071 Ciudad Real, Spain
| | - C Sáez
- Department of Chemical Engineering, Faculty of Chemical Sciences & Technologies, University of Castilla-La Mancha, Campus Universitario s/n, 13071 Ciudad Real, Spain
| | - P Cañizares
- Department of Chemical Engineering, Faculty of Chemical Sciences & Technologies, University of Castilla-La Mancha, Campus Universitario s/n, 13071 Ciudad Real, Spain
| | - L Asensio
- Geoenvironmental Group, Civil Engineering School, University of Castilla-La Mancha, Avda. Camilo José Cela s/n, 13071 Ciudad Real, Spain
| | - V Navarro
- Geoenvironmental Group, Civil Engineering School, University of Castilla-La Mancha, Avda. Camilo José Cela s/n, 13071 Ciudad Real, Spain
| | - M A Rodrigo
- Department of Chemical Engineering, Faculty of Chemical Sciences & Technologies, University of Castilla-La Mancha, Campus Universitario s/n, 13071 Ciudad Real, Spain
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Yustres Á, López-Vizcaíno R, Sáez C, Cañizares P, Rodrigo M, Navarro V. Water transport in electrokinetic remediation of unsaturated kaolinite. Experimental and numerical study. Sep Purif Technol 2018. [DOI: 10.1016/j.seppur.2017.10.009] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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López-Vizcaíno R, Yustres A, Sáez C, Cañizares P, Rodrigo M, Navarro V. Effect of polarity reversal on the enhanced electrokinetic remediation of 2,4-D-polluted soils: A numerical study. Electrochim Acta 2017. [DOI: 10.1016/j.electacta.2017.11.077] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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López-Vizcaíno R, Risco C, Isidro J, Rodrigo S, Saez C, Cañizares P, Navarro V, Rodrigo MA. Scale-up of the electrokinetic fence technology for the removal of pesticides. Part II: Does size matter for removal of herbicides? Chemosphere 2017; 166:549-555. [PMID: 27692679 DOI: 10.1016/j.chemosphere.2016.09.114] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2016] [Revised: 09/23/2016] [Accepted: 09/24/2016] [Indexed: 06/06/2023]
Abstract
This work reports results of the application of electrokinetic fence technology in a 32 m3 -prototype which contains soil polluted with 2,4-D and oxyfluorfen, focusing on the evaluation of the mechanisms that describe the removal of these two herbicides and comparing results to those obtained in smaller plants: a pilot-scale mockup (175 L) and a lab-scale soil column (1 L). Results show that electric heating of soil (coupled with the increase in the volatility) is the key to explain the removal of pollutants in the largest scale facility while electrokinetic transport processes are the primary mechanisms that explain the removal of herbicides in the lab-scale plant. 2-D and 3-D maps of the temperature and pollutant concentrations are used in the discussion of results trying to give light about the mechanisms and about how the size of the setup can lead to different conclusions, despite the same processes are occurring in the soil.
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Affiliation(s)
- R López-Vizcaíno
- Department of Chemical Engineering, Facultad de Ciencias y Tecnologías Químicas, University of Castilla-La Mancha, Campus Universitario s/n, 13071, Ciudad Real, Spain
| | - C Risco
- Department of Chemical Engineering, Instituto de Tecnologías Química y Medioambiental, University of Castilla-La Mancha, Campus Universitario s/n, 13071, Ciudad Real, Spain
| | - J Isidro
- Department of Chemical Engineering, Instituto de Tecnologías Química y Medioambiental, University of Castilla-La Mancha, Campus Universitario s/n, 13071, Ciudad Real, Spain
| | - S Rodrigo
- Department of Chemical Engineering, Instituto de Tecnologías Química y Medioambiental, University of Castilla-La Mancha, Campus Universitario s/n, 13071, Ciudad Real, Spain
| | - C Saez
- Department of Chemical Engineering, Facultad de Ciencias y Tecnologías Químicas, University of Castilla-La Mancha, Campus Universitario s/n, 13071, Ciudad Real, Spain
| | - P Cañizares
- Department of Chemical Engineering, Facultad de Ciencias y Tecnologías Químicas, University of Castilla-La Mancha, Campus Universitario s/n, 13071, Ciudad Real, Spain
| | - V Navarro
- Geoenvironmental Group, Civil Engineering School, University of Castilla-La Mancha, Avda. Camilo José Cela s/n, 13071, Ciudad Real, Spain
| | - M A Rodrigo
- Department of Chemical Engineering, Facultad de Ciencias y Tecnologías Químicas, University of Castilla-La Mancha, Campus Universitario s/n, 13071, Ciudad Real, Spain.
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López-Vizcaíno R, Risco C, Isidro J, Rodrigo S, Saez C, Cañizares P, Navarro V, Rodrigo MA. Scale-up of the electrokinetic fence technology for the removal of pesticides. Part I: Some notes about the transport of inorganic species. Chemosphere 2017; 166:540-548. [PMID: 27692680 DOI: 10.1016/j.chemosphere.2016.09.113] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2016] [Revised: 09/23/2016] [Accepted: 09/24/2016] [Indexed: 06/06/2023]
Abstract
This work describes the application electrokinetic fence technology to a soil polluted with herbicides in a large prototype containing 32 m3 of soil. It compares performance in this large facility with results previously obtained in a pilot-scale mockup (175 L) and with results obtained in a lab-scale soil column (1 L), all of them operated under the same driving force: an electric field of 1.0 V cm-1. Within this wide context, this work focuses on the effect on inorganic species contained in soil and describes the main processes occurring in the prototype facility, as well as the differences observed respect to the lower scale plants. Thus, despite the same processes can be described in the three plants, important differences are observed in the evolution of the current intensity, moisture and conductivity. They can be related to the less important electroosmotic fluxes in the larger facilities and to the very different distances between electrodes, which lead to very different distribution of species and even to a very different evolution of the resulting current intensity. 2-D maps of the main species at different relevant moments of the test are discussed and important information is drawn from them. Ions depletion from soil appears as a very important problem which should be prevented if the effect of natural bioremediation and/or phytoremediation on the removal or organics aims to be accounted.
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Affiliation(s)
- R López-Vizcaíno
- Department of Chemical Engineering, Facultad de Ciencias y Tecnologías Químicas, University of Castilla-La Mancha, Campus Universitario s/n, 13071 Ciudad Real, Spain
| | - C Risco
- Department of Chemical Engineering, Instituto de Tecnologías Química y Medioambiental, University of Castilla-La Mancha, Campus Universitario s/n, 13071 Ciudad Real, Spain
| | - J Isidro
- Department of Chemical Engineering, Instituto de Tecnologías Química y Medioambiental, University of Castilla-La Mancha, Campus Universitario s/n, 13071 Ciudad Real, Spain
| | - S Rodrigo
- Department of Chemical Engineering, Instituto de Tecnologías Química y Medioambiental, University of Castilla-La Mancha, Campus Universitario s/n, 13071 Ciudad Real, Spain
| | - C Saez
- Department of Chemical Engineering, Facultad de Ciencias y Tecnologías Químicas, University of Castilla-La Mancha, Campus Universitario s/n, 13071 Ciudad Real, Spain
| | - P Cañizares
- Department of Chemical Engineering, Facultad de Ciencias y Tecnologías Químicas, University of Castilla-La Mancha, Campus Universitario s/n, 13071 Ciudad Real, Spain
| | - V Navarro
- Geoenvironmental Group, Civil Engineering School, University of Castilla-La Mancha, Avda. Camilo José Cela s/n, 13071 Ciudad Real, Spain
| | - M A Rodrigo
- Department of Chemical Engineering, Facultad de Ciencias y Tecnologías Químicas, University of Castilla-La Mancha, Campus Universitario s/n, 13071 Ciudad Real, Spain.
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14
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López-Vizcaíno R, Navarro V, León MJ, Risco C, Rodrigo MA, Sáez C, Cañizares P. Scale-up on electrokinetic remediation: Engineering and technological parameters. J Hazard Mater 2016; 315:135-143. [PMID: 27209275 DOI: 10.1016/j.jhazmat.2016.05.012] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2016] [Revised: 05/04/2016] [Accepted: 05/05/2016] [Indexed: 06/05/2023]
Abstract
This study analyses the effect of the scale-up of electrokinetic remediation (EKR) processes in natural soils. A procedure is proposed to prepare soils based on a compacting process to obtaining soils with similar moisture content and density to those found in real soils in the field. The soil used here was from a region with a high agrarian activity (Mora, Spain). The scale-up study was performed in two installations at different scales: a mock-up pilot scale (0.175m(3)) and a prototype with a scale that was very similar to a real application (16m(3)). The electrode configuration selected consisted of rows of graphite electrodes facing each other located in electrolyte wells. The discharge of 20mg of 2,4-dichlorophenoxyacetic acid [2,4-D] per kg of dry soil was treated by applying an electric potential gradient of 1Vcm(-1). An increase in scale was observed to directly influence the amount of energy supplied to the soil being treated. As a result, electroosmotic and electromigration flows and electric heating are more intense than in smaller-scale tests (24%, 1% and 25%, respectively respect to the values in prototype). In addition, possible leaks were evaluated by conducting a watertightness test and quantifying evaporation losses.
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Affiliation(s)
- Rubén López-Vizcaíno
- Department of Chemical Engineering, Institute of Chemical & Environmental Technologies, University of Castilla-La Mancha, Campus Universitario s/n, 13071 Ciudad Real, Spain
| | - Vicente Navarro
- Geoenvironmental Group, Civil Engineering School, University of Castilla-La Mancha, Avda. Camilo José Cela s/n, 13071 Ciudad Real, Spain
| | - María J León
- Geoenvironmental Group, Civil Engineering School, University of Castilla-La Mancha, Avda. Camilo José Cela s/n, 13071 Ciudad Real, Spain
| | - Carolina Risco
- Department of Chemical Engineering, Institute of Chemical & Environmental Technologies, University of Castilla-La Mancha, Campus Universitario s/n, 13071 Ciudad Real, Spain
| | - Manuel A Rodrigo
- Department of Chemical Engineering, Faculty of Chemical Sciences & Technologies, University of Castilla-La Mancha, Campus Universitario s/n, 13071 Ciudad Real, Spain.
| | - Cristina Sáez
- Department of Chemical Engineering, Faculty of Chemical Sciences & Technologies, University of Castilla-La Mancha, Campus Universitario s/n, 13071 Ciudad Real, Spain
| | - Pablo Cañizares
- Department of Chemical Engineering, Faculty of Chemical Sciences & Technologies, University of Castilla-La Mancha, Campus Universitario s/n, 13071 Ciudad Real, Spain
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Risco C, Rubí-Juárez H, Rodrigo S, López-Vizcaíno R, Saez C, Cañizares P, Barrera-Díaz C, Navarro V, Rodrigo MA. Removal of oxyfluorfen from spiked soils using electrokinetic soil flushing with the surrounding arrangements of electrodes. Sci Total Environ 2016; 559:94-102. [PMID: 27058128 DOI: 10.1016/j.scitotenv.2016.03.174] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2016] [Revised: 03/09/2016] [Accepted: 03/23/2016] [Indexed: 06/05/2023]
Abstract
This work reports the results of a study in which the remediation of soil that undergoes an accidental discharge of oxyfluorfen is carried out by using electrokinetic soil flushing (EKSF). Two different electrode configurations were tested, consisting of several electrodes surrounding an electrode of different polarity (so-called 1A6C, one anode surrounded by six cathodes, and 1C6A, one cathode surrounded by six cathodes). A pilot plant scale was used (with a soil volume of 175dm(3)) to perform the studies. During the tests, different parameters were measured daily (flowrates, pH, electrical conductivity and herbicide concentration in different sampling positions). Furthermore, at the end of the test, a complete post-mortem analysis was carried out to obtain a 3-D map of the pollution, pH and electrical conductivity in the soil. The results demonstrate that electrode arrangement is a key factor for effective pollutant removal. In fact, the 1A6C configuration improves the removal rate by 41.3% versus the 27.0% obtained by the 1C6A configuration after a period of 35days. Finally, a bench mark comparison of this study of soil remediation polluted with 2,4-D allows for significant conclusions about the scale-up and full-scale application of this technology.
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Affiliation(s)
- C Risco
- Department of Chemical Engineering, Instituto de Tecnologías Química y Medioambiental, University of Castilla-La Mancha, Campus Universitario s/n, 13071 Ciudad Real, Spain
| | - H Rubí-Juárez
- Facultad de Química, Universidad Autónoma del Estado de México, Paseo Colón intersección Paseo Tollocan S/N, C.P., 50120, Toluca, Estado de México, Mexico
| | - S Rodrigo
- Department of Chemical Engineering, Facultad de Ciencias y Tecnologías Químicas, University of Castilla-La Mancha, Campus Universitario s/n, 13071 Ciudad Real, Spain
| | - R López-Vizcaíno
- Department of Chemical Engineering, Facultad de Ciencias y Tecnologías Químicas, University of Castilla-La Mancha, Campus Universitario s/n, 13071 Ciudad Real, Spain
| | - C Saez
- Department of Chemical Engineering, Instituto de Tecnologías Química y Medioambiental, University of Castilla-La Mancha, Campus Universitario s/n, 13071 Ciudad Real, Spain
| | - P Cañizares
- Department of Chemical Engineering, Instituto de Tecnologías Química y Medioambiental, University of Castilla-La Mancha, Campus Universitario s/n, 13071 Ciudad Real, Spain
| | - C Barrera-Díaz
- Facultad de Química, Universidad Autónoma del Estado de México, Paseo Colón intersección Paseo Tollocan S/N, C.P., 50120, Toluca, Estado de México, Mexico
| | - V Navarro
- Geoenvironmental Group, Civil Engineering School, University of Castilla-La Mancha, Avda. Camilo José Cela s/n, 13071 Ciudad Real, Spain
| | - M A Rodrigo
- Department of Chemical Engineering, Instituto de Tecnologías Química y Medioambiental, University of Castilla-La Mancha, Campus Universitario s/n, 13071 Ciudad Real, Spain.
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16
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Risco C, Rodrigo S, López-Vizcaíno R, Sáez C, Cañizares P, Navarro V, Rodrigo MA. Electrokinetic flushing with surrounding electrode arrangements for the remediation of soils that are polluted with 2,4-D: A case study in a pilot plant. Sci Total Environ 2016; 545-546:256-265. [PMID: 26747990 DOI: 10.1016/j.scitotenv.2015.12.065] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2015] [Revised: 12/14/2015] [Accepted: 12/15/2015] [Indexed: 06/05/2023]
Abstract
This work aimed to evaluate electrokinetic soil flushing (EKSF) technologies for the removal of 2,4-dichlorophenoxyacetic acid (2,4-D) from spiked soils using an electrode configuration consisting of one cathode surrounded by six anodes (1c6a) and one anode surrounded by 6 cathodes (1a6c). Experiments were conducted for over one month in a bench-scale set-up (175 dm(3) of capacity) that was completely automated and operated at a constant electric field (1.0V cm(-1)). The electrical current, temperature, pH, moisture and pollutant concentration in electrolyte wells were monitored daily, and at the end of the experiments, an in-depth sectioned analysis of the complete soil section (post-mortem analysis) was conducted. Despite the geometric similarity, the two strategies led to very different results mainly in terms of water and herbicide mobilization, whereas pH and conductivity do not depend strongly on the electrode configuration. The volume of water extracted from cathodes with 1a6c is seven times higher than that of the 1c6a strategy. Herbicide was transported to the anode wells by electromigration and then dragged toward the cathode wells by electro-osmotic fluxes, with the first process being much more important. The configuration 1c6a was the most efficient and attained a transfer of 70% of the herbicide contained in the soil to flushing water in 35 days. These results outperform those obtained by the configuration 1a6c, for which less than 8% of the herbicide was transferred to flushing fluids in a much longer time (58 days).
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Affiliation(s)
- C Risco
- Department of Chemical Engineering, Instituto de Tecnologías Química y Medioambiental, University of Castilla-La Mancha, Campus Universitario s/n, 13071 Ciudad Real, Spain
| | - S Rodrigo
- Department of Chemical Engineering, Instituto de Tecnologías Química y Medioambiental, University of Castilla-La Mancha, Campus Universitario s/n, 13071 Ciudad Real, Spain
| | - R López-Vizcaíno
- Department of Chemical Engineering, Instituto de Tecnologías Química y Medioambiental, University of Castilla-La Mancha, Campus Universitario s/n, 13071 Ciudad Real, Spain
| | - C Sáez
- Department of Chemical Engineering, Facultad de Ciencias y Tecnologías Químicas, University of Castilla-La Mancha, Campus Universitario s/n, 13071 Ciudad Real, Spain
| | - P Cañizares
- Department of Chemical Engineering, Facultad de Ciencias y Tecnologías Químicas, University of Castilla-La Mancha, Campus Universitario s/n, 13071 Ciudad Real, Spain
| | - V Navarro
- Geoenvironmental Group, Civil Engineering School, University of Castilla-La Mancha, Avda. Camilo José Cela s/n, 13071 Ciudad Real, Spain
| | - M A Rodrigo
- Department of Chemical Engineering, Facultad de Ciencias y Tecnologías Químicas, University of Castilla-La Mancha, Campus Universitario s/n, 13071 Ciudad Real, Spain.
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Risco C, Rodrigo S, López-Vizcaíno R, Yustres A, Sáez C, Cañizares P, Navarro V, Rodrigo M. Electrochemically assisted fences for the electroremediation of soils polluted with 2,4-D: A case study in a pilot plant. Sep Purif Technol 2015. [DOI: 10.1016/j.seppur.2015.10.006] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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18
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López-Vizcaíno R, Navarro V, Alonso J, Yustres Á, Cañizares P, Rodrigo MA, Sáez C. Geotechnical behaviour of low-permeability soils in surfactant-enhanced electrokinetic remediation. J Environ Sci Health A Tox Hazard Subst Environ Eng 2015; 51:44-51. [PMID: 26488188 DOI: 10.1080/10934529.2015.1079106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Electrokinetic processes provide the basis of a range of very interesting techniques for the remediation of polluted soils. These techniques consist of the application of a current field in the soil that develops different transport mechanisms capable of mobilizing several types of pollutants. However, the use of these techniques could generate nondesirable effects related to the geomechanical behavior of the soil, reducing the effectiveness of the processes. In the case of the remediation of polluted soils with plasticity index higher than 35, an excessive shrinkage can be observed in remediation test. For this reason, the continued evaporation that takes place in the sample top can lead to the development of cracks, distorting the electrokinetic transport regime, and consequently, the development of the operation. On the other hand, when analyzing silty soils, in the surroundings of injection surfactant wells, high seepages can be generated that give rise to the development of piping processes. In this article methods are described to allow a reduction, or to even eliminate, both problems.
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Affiliation(s)
- Rubén López-Vizcaíno
- a Department of Chemical Engineering , Facultad de Ciencias y Tecnologías Químicas, University of Castilla-La Mancha , Ciudad Real , Spain
| | - Vicente Navarro
- b Geoenvironmental Group, Civil Engineering School, University of Castilla-La Mancha , Ciudad Real , Spain
| | - Juan Alonso
- b Geoenvironmental Group, Civil Engineering School, University of Castilla-La Mancha , Ciudad Real , Spain
| | - Ángel Yustres
- b Geoenvironmental Group, Civil Engineering School, University of Castilla-La Mancha , Ciudad Real , Spain
| | - Pablo Cañizares
- a Department of Chemical Engineering , Facultad de Ciencias y Tecnologías Químicas, University of Castilla-La Mancha , Ciudad Real , Spain
| | - Manuel A Rodrigo
- a Department of Chemical Engineering , Facultad de Ciencias y Tecnologías Químicas, University of Castilla-La Mancha , Ciudad Real , Spain
| | - Cristina Sáez
- a Department of Chemical Engineering , Facultad de Ciencias y Tecnologías Químicas, University of Castilla-La Mancha , Ciudad Real , Spain
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López-Vizcaíno R, Alonso J, Cañizares P, León MJ, Navarro V, Rodrigo MA, Sáez C. Electroremediation of a natural soil polluted with phenanthrene in a pilot plant. J Hazard Mater 2014; 265:142-150. [PMID: 24361491 DOI: 10.1016/j.jhazmat.2013.11.048] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2013] [Revised: 11/19/2013] [Accepted: 11/21/2013] [Indexed: 06/03/2023]
Abstract
In this work, a pilot plant with two rows of three electrodes in semipermeable electrolyte wells was used to study the electrokinetic treatment of a natural soil polluted with phenanthrene (PHE). The electrokinetic pilot plant was an open system, i.e., there was direct contact between the soil and air. To increase the solubility of phenanthrene, thereby enhancing its transport through the soil, an aqueous solution of the anionic surfactant dodecyl sulfate was used as a flushing fluid. The results show that at the pilot scale considered, gravity and evaporation fluxes are more relevant than electrokinetic fluxes. Contrary to observations at the laboratory scale, desorption of PHE promoted by electric heating appears to be a significant removal mechanism at the pilot scale. In addition, PHE is dragged by the electroosmotic flow in the cathodic wells and by electrophoresis after interaction of the surfactant with phenanthrene in the anodic wells. In spite of the long treatment time (corresponding to an energy consumption over 500kWhm(-3)), the average removal attained was only 25%.
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Affiliation(s)
- R López-Vizcaíno
- Department of Chemical Engineering, Facultad de Ciencias y Tecnologías Químicas, University of Castilla-La Mancha, Campus Universitario s/n, 13071 Ciudad Real, Spain
| | - J Alonso
- Geoenvironmental Group, Civil Engineering School, University of Castilla-La Mancha, Avda. Camilo José Cela s/n, 13071 Ciudad Real, Spain
| | - P Cañizares
- Department of Chemical Engineering, Facultad de Ciencias y Tecnologías Químicas, University of Castilla-La Mancha, Campus Universitario s/n, 13071 Ciudad Real, Spain
| | - M J León
- Geoenvironmental Group, Civil Engineering School, University of Castilla-La Mancha, Avda. Camilo José Cela s/n, 13071 Ciudad Real, Spain
| | - V Navarro
- Geoenvironmental Group, Civil Engineering School, University of Castilla-La Mancha, Avda. Camilo José Cela s/n, 13071 Ciudad Real, Spain
| | - M A Rodrigo
- Department of Chemical Engineering, Facultad de Ciencias y Tecnologías Químicas, University of Castilla-La Mancha, Campus Universitario s/n, 13071 Ciudad Real, Spain
| | - C Sáez
- Department of Chemical Engineering, Facultad de Ciencias y Tecnologías Químicas, University of Castilla-La Mancha, Campus Universitario s/n, 13071 Ciudad Real, Spain.
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López-Vizcaíno R, Sáez C, Cañizares P, Rodrigo M. The use of a combined process of surfactant-aided soil washing and coagulation for PAH-contaminated soils treatment. Sep Purif Technol 2012. [DOI: 10.1016/j.seppur.2011.11.038] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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López-Vizcaíno R, Sáez C, Cañizares P, Navarro V, Rodrigo MA. Influence of the Type of Surfactant on the Mobility of Flushing Fluids for Electro-Remediation Processes. SEP SCI TECHNOL 2011. [DOI: 10.1080/01496395.2011.594477] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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López-Vizcaíno R, Sáez C, Mena E, Villaseñor J, Cañizares P, Rodrigo MA. Electro-osmotic fluxes in multi-well electro-remediation processes. J Environ Sci Health A Tox Hazard Subst Environ Eng 2011; 46:1549-1557. [PMID: 22029697 DOI: 10.1080/10934529.2011.609458] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
In recent years, electrokinetic techniques on a laboratory scale have been studied but few applications have been assessed at full-scale. In this work, a mock-up plant with two rows of three electrodes positioned in semipermeable electrolyte wells has been used to study the electro-osmotic flux distribution. Water accumulated in the cathodic wells when an electric voltage gradient was applied between the two electrode-well rows. Likewise, slight differences in the water flux were observed depending on the position and number of electrodes used and on the voltage gradient applied. Results show that the electro-osmotic flow did not increase proportionally with the number of electrodes used. During the start-up of the study, there was an abrupt change in the current density, pH and conductivity of the soil portions closest to electrodic wells due to electrokinetic processes. These differences can be explained in terms of the complex current distributions from anode and cathode rows.
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Affiliation(s)
- Rubén López-Vizcaíno
- Department of Chemical Engineering, University of Castilla-La Mancha, Ciudad Real, Spain
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