Engineering news
The system was successfully tested at Sellafield in 2014.
Costain has received £180,000 of funding to continue the development of an advanced robotic system that will make the disposal of radioactive waste safer, quicker and more cost-effective.
Innovate UK has granted a total of £350,000 to D:EEP, which is a collaborative project between Costain and Cumbria-based imaging technology specialist Createc.
The funding for the collaboration is part of a joint £13 million initiative between Innovate UK, the Nuclear Decommissioning Authority and the Department of Energy and Climate Change to stimulate the UK's civilian nuclear power sector. Costain will use the funding to carry out further development work on a system that provides a detailed, real-time survey of levels of radioactive contamination in concrete waste.
Current methods for determining depth of contamination involve taking random core samples from the contaminated materials and then sending these to a lab for analysis, which normally takes between six to eight weeks. Resulting decommissioning plans will often involve the removal of 20mm over the entire surface to capture the Intermedia Level Waste (ILW).
The D:EEP system achieves “whole picture interpolation” by utilises existing off-the-shelf spectrometers in conjunction with data logging hardware for data capture. The linear stages are computer controlled for automation purposes allowing it to be setup and remotely monitored, thus reducing the dose exposure time for the operatives.
By utilising linear stages the system is able to capture individual readings across much wider areas than current methods. Designed for pond walls, which can be approximately 8m high by 30m long, the readings can be at preset spacings from 10mm apart upwards. This allows individual areas to be targeted, for example cracks.
Matt Butler, Costain project manager, said: “Our system provides whole picture interpolation. This means we can accurately measure the depth of contamination and classify the waste as Intermediate Level Waste (ILW) or Low Level Waste (LLW).
“This is vital: having a good understanding of what ILW and what is LLW can mean less waste and fewer storage facilities. This can result in major, long-term savings. We estimate the Nuclear Decommissioning Authority could potentially save just under £1.5 billion.”
The huge amount of data collected by the system means that data analysis is currently carried out off site by computer. Results can be shown by a heat map of the contamination, individual contamination depths and a 3D surface model of boundary relative to actual surface to build up. This creates an entire picture and can be used to target specific 'hot spots' at ILW, which allows operators to come up with an optimised decommissioning methodology, reducing the need for lengthy and disruptive whole top surface removal used in current methods.
Work on the five-year project began in February 2013. Feasibility studies at the Chapelcross nuclear power station in April 2013 and at Sellafield in March 2014 proved the system worked. The additional funding will be utilised to carry out further case studies and bring the system to market. Butler said: “We see it being used not just in the nuclear power industry but also at defence and health care sites – in fact wherever in the world there is radioactive waste."
Project partner Createc's N-Visage technology is also being utilised to aid in the clean-up at Fukushima, and has been used in both walking robots and drones to create accurate 3D snapshots of the nuclear site. Createc is in negotiations to make N-Visage the main system for radioactivity identification used at Fukushima and has also signed a contract with the Japanese government to develop a camera designed to go into reactors’ cores and record images.