Further funding confirmed for salt concentration measurement challenge

Following the completion of five feasibility studies exploring the measurement of salt concentrations within Sellafield Ltd’s Vitrified Product Store (VPS), two projects have been identified as having the potential for further investigation.

In order to effectively monitor and safely maintain the VPS, Sellafield Ltd needs to measure salt concentrations and therefore the potential for corrosion of a mild and stainless-steel structure referred to as the Tube Module Assembly (TMA) within the VPS. Solution providers were invited to solve all or part of the challenge of accessing the TMA via vertical air ducts containing a series of bends, in an active environment, and measuring salt concentrations on the support structure.

The first project to be awarded proof of concept funding is a collaboration between the Fraunhofer Centre for Applied Photonics (CAP), the University of Strathclyde and the National Nuclear Laboratory (NNL). Fraunhofer CAP will lead the project and provide the hardware in the form of an infrared spectroscopy sensor deployed using existing NNL technology. The University of Strathclyde is providing bespoke software to analyse and process the data obtained and convert it into intuitive colour maps that highlight the concentration and type of salts present in the target environment. It is hoped that this non-destructive solution will allow the characterisation of salts in hazardous environments (type of salt and concentration) without needing any contact with the surface being inspected.

For their project, Bristol-based SME Clifton Photonics will use the high levels of radiation in the VPS to their advantage by observing the atypical optical properties radiation imparts on salts. They will produce a fibre optic probe that can excite and detect the characteristic optical emissions from the irradiated salt deposits to non-destructively identify them. The probes used are long enough and flexible enough to access the lower plenum of the VPS and do not contain any electronics that could be damaged in the high levels of radiation.

The projects are expected to conclude early next year.