Change search
ReferencesLink to record
Permanent link

Direct link
Nitrate Removal by Continuous Electropermutation Using Ion-Exchange Textile: I. Modeling
KTH, School of Engineering Sciences (SCI), Centres, Faxén Laboratory.
KTH, School of Engineering Sciences (SCI), Centres, Faxén Laboratory.ORCID iD: 0000-0002-2906-9306
KTH, School of Engineering Sciences (SCI), Centres, Faxén Laboratory.ORCID iD: 0000-0002-9392-9059
2006 (English)In: Journal of the Electrochemical Society, ISSN 0013-4651, Vol. 153, no 4, D51-D61 p.Article in journal (Refereed) Published
Abstract [en]

This paper presents a steady-state model of the feed compartment of an electropermutation cell, used for nitrate removal, with ion exchange textiles incorporated as a conducting spacer. In the model the ion-exchange textile is treated as a porous medium and volume averaging is applied to obtain a macrohomogeneous two-phase model. The ion-exchange between the two phases is modeled assuming that the rate-determining step is the mass-transfer resistance on the liquid side of the phase interface. Analysis of the model equations reveals appropriate simplifications. The influence of the governing dimensionless numbers is investigated through simulations based on the model.

Place, publisher, year, edition, pages
2006. Vol. 153, no 4, D51-D61 p.
Keyword [en]
high-resistivity water, electrodialysis, membranes, electrodeionization, transport, anions, beds
National Category
Chemical Sciences
URN: urn:nbn:se:kth:diva-5790DOI: 10.1149/1.2170597ISI: 000235723600039ScopusID: 2-s2.0-33644814154OAI: diva2:10287
QC 20101115Available from: 2006-05-23 Created: 2006-05-23 Last updated: 2011-01-05Bibliographically approved
In thesis
1. Electropermutation assisted by ion-exchange textile: removal of nitrate from drinking water
Open this publication in new window or tab >>Electropermutation assisted by ion-exchange textile: removal of nitrate from drinking water
2006 (English)Doctoral thesis, comprehensive summary (Other scientific)
Abstract [en]

Increased levels of nitrate in ground water have made many wells unsuitable as sources for drinking water. In this thesis an ion-exchang eassisted electromembrane process, suitable for nitrate removal, is investigated both theoretically and experimentally. An ion-exchange textile material is introduced as a conducting spacer in the feed compartment of an electropermutation cell. The sheet shaped structure of the textile makes it easy to incorporate into the cell. High permeability and fast ion-exchange kinetics, compared to ion-exchange resins, are other attractive features of the ion-exchange textile.

A steady-state model based on the conservation of the ionic species is developed. The governing equations on the microscopic level are volume averaged to give macro-homogeneous equations. The model equations are analyzed and relevant simplifications are motivated and introduced. Dimensionless parameters governing the continuous electropermutation process are identified and their influence on the process are discussed. The mathematical model can be used as a tool when optimising the process parameters and designing equipment.

An experimental study that aimed to show the positive influence of using the ion-exchange textile in the feed compartment of an continuous electropermutation process is presented. The incorporation of the ion-exchange textile significantly improves the nitrate removal rate at the same time as the power consumption is decreased. A superficial solution of sodium nitrate with a initial nitrate concentration of 105 ppm was treated. A product stream with less than 20 ppm nitrate could be obtained, in a single pass mode of operation. Its concluded from these experiments that continuous electropermutation using ion-exchange textile provides an interesting alternative for nitrate removal, in drinking water production. The predictions of the mathematical model are compared with experimental results and a good agreement is obtained.

Enhanced water dissociation is known to take place at the surface of ion-exchange membranes in electromembrane processes operated above the limiting current density. A model for this enhanced water dissociation in presented in the thesis. The model makes it possible to incorporate the effect of water dissociation as a heterogeneous surface reaction. Results from simulations of electropermutation with and without ion-exchange textile incorporated are presented. The influence of the water dissociation is investigated with the developed model.

Place, publisher, year, edition, pages
Stockholm: KTH, 2006
Trita-MEK, ISSN 0348-467X ; 2006:10
Ion-exchange textile, Ion-exchange membrane, Electropermutation, Electroextraction, Electrodialysis, Electrodeionisation, Modeling, Conducting spacer, Nitrate removal, Water treatment, Water dissociation
National Category
Fluid Mechanics and Acoustics
urn:nbn:se:kth:diva-3992 (URN)
Public defence
2006-06-08, D3, Lindstedtsvägen 5, Stockholm, 10:00
QC 20101118Available from: 2006-05-23 Created: 2006-05-23 Last updated: 2010-11-18Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full textScopus

Search in DiVA

By author/editor
Danielsson, Carl-OlaDahlkild, AndersBehm, Mårten
By organisation
Faxén Laboratory
In the same journal
Journal of the Electrochemical Society
Chemical Sciences

Search outside of DiVA

GoogleGoogle Scholar
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Altmetric score

Total: 48 hits
ReferencesLink to record
Permanent link

Direct link