Vattenfall signs agreement with Westinghouse for decommissioning work at Ringhals NPP19 August 2021
Vattenfall has signed an agreement with Westinghouse Electric Sweden AB for dismantling of reactor tanks and their internal parts as well as fuel racks at units 1&2 of the Ringhals NPP in southern Sweden. It is thus clear how these large radioactive components are to be dismantled and disposed of, which also sets the framework for other dismantling work at Ringhals 1 and 2.
“Vattenfall´s mission is to dismantle and dispose of used reactors and other components in the same way they have been operated: safely and efficiently,” said Christopher Eckerberg, Head of Nuclear Decommissioning at Vattenfall. The agreement with Westinghouse Electric means that it is clear how the large radioactive components at Ringhals 1 and 2 shall be dismantled and this also sets the framework for other dismantling activities in the facilities.”
Katarina Gereborg, responsible for the procurement process at Vattenfall commented: “We received several good offers but opted for Westinghouse Electric since they best met our evaluation criteria. The agreement is a so-called turnkey contract where the supplier is responsible for the entire work, given that Vattenfall´s demands are fulfilled.”
Westinghouse Electric Sweden CEO Aziz Dag noted: “We are grateful for Vattenfall's continued confidence in our entire life cycle capacity within the nuclear power industry. ASEA Atom, which today is Westinghouse, built Ringhals 1 and Westinghouse built Ringhals 2. With this agreement, we close the circle with safe dismantling of the reactors.”
The physical work of dismantling the large radioactive components at Ringhals 1&2 will start on 1 April 2023 at the earliest. The exact value of the agreement is not stated for business reasons, but it is estimated at several hundred million kronor ($1=SEK8.7).
Initially, the internal parts of the reactor tank at Ringhals 1 will be segmented, thereafter the internal parts at Ringhals 2. The internal parts are the most radioactive. The work is performed with remote controlled underwater tools shield from radiation. Thereafter the reactor tanks are segmented, starting at Ringhals 1, then the water is emptied, and the tank is covered by a lid. The tank is cut into rings from top to bottom with remote controlled tools which are operated from a station inside the facility. The fuel racks are decontaminated and then cut down to manageable sizes.
In total the components weigh around 1 500 tonnes most of which is radioactive. Highly active material such as nuclear fuel will have been removed before work starts, and the remaining material is of moderate or low radioactivity. The material is segmented and packed in approved containers and is to be stored at the Ringhals site until the final repositories are extended. All material is disposed of with safety as top priority and in accordance with laws and regulations. Vattenfall estimates that the dismantling of Ringhals 1&2 will result in 340 000 tonnes of waste, of which 5-10% is radioactive. Material which is proved to be free from radioactivity is used as spare parts, recycled at the facilities as landfill, or recycled in a conventional manner.
The radiological dismantling of Ringhals 1&2 is planned to start by the end of 2022 and last for almost a decade. The decommissioning of nuclear power in Sweden has secure financing: since the 1970s the nuclear companies have allocated funds for decommissioning and final repositories. The money is administrated by the Nuclear Waste Fund.
Westinghouse said its engineers will start the dismantling process digitally with 3D modelling of all the cutting and packaging that will be performed onsite. The onsite work is executed by a team of highly skilled Westinghouse technicians who have been involved in dismantling many nuclear reactors in Europe. For the reactor internals, they will use mechanical underwater remote-controlled equipment to ensure the highest degree of safety and efficiency. For the reactor pressure vessels, dry thermal cutting technologies will be used for most of the parts. When the process is complete, all materials will be packed and safely disposed of in approved containers.