229-EPE : Electrokinetic processes in civil and environmental engineering

Technical Committee 229-EPE

General Information

Chair: Dr. Lisbeth OTTOSEN
Deputy Chair: Dr. Marta CASTELLOTE
Activity starting in: 2008
Activity ending in: 2014
Cluster B

Subject matter

Electrokinetics inclusive electromigration is a powerful tool for removal and supply of matter into or out from porous materials. Electrokinetic transport processes are utilized in civil engineering for repair and maintenance purposes and in environmental engineering for contaminant removal. The two most well-known methods are desalination of concrete and soil remediation, respectively, but there are also other possible applications within both engineering fields as re-impregnation of wood, desalination of brick masonry, upgrading of fly ashes for use in concrete, remediation of harbour sediment and wastewater sludge.

Even though there are many topics of common interest between civil and environmental engineers working with electrokinetics there is no tradition for interdisciplinary collaboration and it is exactly the major goal of the proposed TC to open and stimulate such collaboration. It is expected that utilization of the interdisciplinary collaboration will enhance the rate of development and implementation of the electrokinetic methods due to the synergy effect and increased knowledge level in both fields. A fundamental description of the system with a porous material subjected to application of an electric DC field is formulated.

Examples of topics for the TC (the list is finalized at the first TC meeting):
Increase transport rate of target ions. The transport rate for ions in applied electric fields in a porous material is typically less than 1 cm/day. The main factor determining the transport rate is often desorption processes and in different materials desorption has been identified to be the limiting step (e.g. both in concrete and soil). A fundamental description of the general system for electromigration in a porous material, inclusive desorption, could be beneficial to all working with electrokinetic treatment.
Matrix changes. The fundamental description should also include the possible matrix changes, since these have been seen and they have crucial importance to the applicability of the methods and the reuse of the treated materials. This description could be advantageous both in the case where matrix changes is an unwanted effect and where electrokinetics is used to obtain matrix changes.
Electrode units. Choice and optimization of electrode material, design and placement. Control of the products from the electrode processes by neutralization of the acid and base produced before pH in the porous material to be treated is changed unwanted.

Terms of reference

Researchers in different countries around the world are presently developing practical solutions based on electrokinetics for solving various problems. The aim of the TC is to assemble the various pieces of knowledge generated and reach a common fundamental description of the most important parameters. During this work knowledge gaps are identified and common research projects are initialized to fill these gaps. The major aim is to improve the practical solutions and enhance the development. The conclusions of the TC are expected within 3-4 working years.

The regular and correspondent members to be recruited are recognized experts in the domain. The TC will include representatives of four world regions: Europe, Northern America, Southern America and Asia and it is aimed that the findings from the TC will be disseminated at local level by the different TC members. Also at a local level collaboration between researchers and practitioners should be supported or initiated to implement the findings from the TC.

Detailed working programme

The work of the TC will first focus on bringing together the expertise and knowledge of each participating member and the members are recruited between both civil engineers and environmental engineers. This synthesis of expertise will be done at the first TC meeting. It will help identify knowledge gaps and points of common interest for further focus in the TC.

On this base, the future work of the TC will process in parallel the following topics:
- Modeling
- Experimental work
- Validation of the proposed model by cross comparison with the experimental results at working meetings of the TC
- Organization of Ph.D. course “Electrokinetics in Civil and Environmental Enginering” to be held in Lyngby, Denmark in October 2008
- Organization of international meeting (one day) in adjacent to the biannual conference 'EREM- Electrokinetic remediation'. The conference is held in Portugal in 2009. The place for the 2011 conference is not decided yet, but also here the TC will organize a one-day meeting.
- Organization of an international workshop (2012) for presentation of state-of-the-art and spreading of knowledge obtained in the TC
- Preparation of state-of-the-art report focusing both on fundamental description of the system and practical application

Technical environment

The major aim of the TC is to bring two groups of people together, who have no tradition for collaboration. Thus there is no former common project to build on.
The environmental engineers working with electrokinetics have had an informal network (for the past decade) with the primary aim to organize the bi-annually conference 'EREM Electrokinetic remediation' and this network can be utilized in the proposed TC.

Expected achievements

- Fundamental description of electrokinetics in porous materials
- Recommendations for practitioners
- Computational calculations
- Web page (as communication tool)
- International Ph.D. course 'Electrokinetics in Civil and Environmental Engineering'
- International one-day meetings and an international workshop
- State-of-the-art report

Dissemination of knowledge
- Publication of results in scientific journals and presentation at conferences by the respective members of the TC
- Regular reports in Materials and structures and 'Journal of Hazardous Materials'
- At the end of the TC: publication of final state-of-the-art report summarizing the main results and the general conclusions in a dedicated international workshop.

Group of users

Academics and scientists interested in improving the fundamental knowledge and possibilities for utilizing electrokinetic transport processes in porous media, as well as practitioners offering electrokinetic treatment.

Specific use of the results

The results obtained are based on the synergy between two major groups working with electrokinetic methods for different purposes. It is expected that the synergy will bring the research and development significant steps forward in both fields. Further it is also expected that the conclusions can be utilized directly by the practitioners already offering electrokinetic techniques.