Articles | Volume 7, issue 5
Solid Earth, 7, 1281–1292, 2016

Special issue: Pore-scale tomography & imaging - applications, techniques...

Solid Earth, 7, 1281–1292, 2016

Review article 06 Sep 2016

Review article | 06 Sep 2016

Recent developments in neutron imaging with applications for porous media research

Anders P. Kaestner1, Pavel Trtik1, Mohsen Zarebanadkouki2, Daniil Kazantsev3,4, Michal Snehota5, Katherine J. Dobson6,7, and Eberhard H. Lehmann1 Anders P. Kaestner et al.
  • 1Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institut, Villigen, Switzerland
  • 2Division of Soil Hydrology, University of Goettingen, Goettingen, Germany
  • 3Manchester X-Ray Imaging Facility, School of Materials, University of Manchester, Manchester, UK
  • 4Manchester X-Ray Imaging Facility, Research Complex at Harwell, Didcot, UK
  • 5Faculty of Civil Engineering, Czech Technical University in Prague, Prague, Czech Republic
  • 6Ludwig-Maximilians Universität München, Department für Geo-und Umweltwissenschaften, 80333 Munich, Germany
  • 7Department of Earth Sciences, Durham University, Durham, DH1 3LE, UK

Abstract. Computed tomography has become a routine method for probing processes in porous media, and the use of neutron imaging is especially suited to the study of the dynamics of hydrogenous fluids, and of fluids in a high-density matrix. In this paper we give an overview of recent developments in both instrumentation and methodology at the neutron imaging facilities NEUTRA and ICON at the Paul Scherrer Institut. Increased acquisition rates coupled to new reconstruction techniques improve the information output for fewer projection data, which leads to higher volume acquisition rates. Together, these developments yield significantly higher spatial and temporal resolutions, making it possible to capture finer details in the spatial distribution of the fluid, and to increase the acquisition rate of 3-D CT volumes. The ability to add a second imaging modality, e.g., X-ray tomography, further enhances the feature and process information that can be collected, and these features are ideal for dynamic experiments of fluid distribution in porous media. We demonstrate the performance for a selection of experiments carried out at our neutron imaging instruments.

Short summary
Experiments to determine the location and displacement of fluids in porous media are of high interest to verify flow and transport models. Neutron imaging presents, due to the high sensitivity to hydrogen, an ideal method to provide 3-D information about fluid distribution on the scale of a few tens of microns in a dense matrix of a sample container. We report instrumentation and method developments that increase spatial or temporal resolution, and demonstrate the performance in case studies.