Ansaldo Nuclear develops robot for complex nuclear waste removal
After two years of design and manufacture, Ansaldo Nuclear has provided a bespoke robot to recover 2,000 drums of radioactive waste from hard-to-access storage locations at the decommissioned Caorso nuclear power plant in Italy.
As part of one of the biggest and most complex decommissioning projects in the nuclear industry, the project involves the treatment and conditioning of around 860 tonnes of radioactive ion exchange resins and sludges which are still contained in two temporary storage buildings at the Caorso facility.
This waste represents more than 90% of the contamination inventory at the plant.
Ansaldo Nuclear was contracted by Società Gestione Impianti Nucleari (Sogin) for the retrieval, transport, treatment and conditioning of the spent resins and sludges. In total, 5600 200kg drums of Caorso’s radioactive waste will be transported to a waste storage facility in Slovakia, where it will be stabilised via incineration and finally conditioned.
To enable the retrieval project to start in January, Ansaldo Nuclear designed, built and operated a bespoke machine retrieval system robot to retrieve 2,000 drums of radioactive waste which were stored in a variety of niches within the temporary storage facilities at Caorso.
Overseeing the project was project engineer Francesca Maggini, who said that “the extent of the logistical challenge presented by this phase of the Caorso decommissioning project cannot be underestimated”.
“The unique nature of nuclear decommissioning means it is important to face each decommissioning project as an entirely new challenge. You cannot simply repeat the successes of the past – you must pioneer and develop bespoke solutions in order to see the best results. Through effective innovation and installation, we have enabled the decommissioning of Caorso to continue. Ansaldo Nuclear has been involved with the decommissioning of Caorso since 2000, and we’re proud to remain on this substantial project today.”
The robot, which was used to retrieve, verify, seal and pack the radioactive drums, took six months to build and install. Controlled remotely, with a double operating system in place in case of system failure, it is capable of self-recovery in the event of earthquakes or other external safety issues.
Francesco Orzelli, designer and structural analyst at Ansaldo Nuclear, said the robot “was extremely effective, having been designed from the start with safety, efficiency and adaptability as key priorities”.
“One of the key challenges was that we were unable to access the area to take detailed measurements, so the robot had to be constructed to be as compact as possible to allow enough clearance. In doing this, we first created a fully-functioning, 3D model, complete with all mechanical components, to allow us to develop a small machine with significant capabilities.
“We received only the boundary conditions from the customer. This meant Ansaldo Nuclear not only had to manufacture and install an automated retrieval robot, but develop the solution as well – a process which took two years. Through proactive planning and careful implementation, we were able to develop a robot with the freedom and adaptability to retrieve all the drums required, which has allowed Caorso to continue its decommissioning process on schedule.”