JPDR(Japan Power Demonstration Reactor)
Dismantling of Reactor Components and the Biological Shield
Various techniques were applied to remove the JPDR's reactor and biological shield concrete.
For the removal of the main components of the reactor, the reactor's surrounding peripheral equipment was first removed. The core components of the reactor vessel, which had the highest level of radioactivity, were cut by a remote plasma arc cutter while remaining submerged in water and then removed. For dismantling the nuclear reactor pressure vessel (PV), in order to partition the vessel under water, the inner water-sealing cylinder was attached between the PV and the biological shield after the piping had been disconnected by shaped explosives, and disc cutter. The highly activated portion of the PV was cut into blocks using an arc saw cutter. Concrete which had been only slightly activated was demolished by controlled blasting. Useful data and knowledge on dismantling were obtained through the project.
- Ⅰ.Plasma Arc Cutting System / Removal of reactor internals
- Ⅱ.Arc Saw Cutting System / Removal of reactor pressure vessel
- Ⅲ.Disk Cutting System / Removal of piping connected to reactor pressure vessel
- Ⅳ.Shaped Explosive Pipe Cutting System / Removal of piping connected to reactor pressure vessel
- Ⅴ.Mechanical Cutting System / Removal of biological shield concrete
- Ⅵ.Water Jet Cutting System / Removal of biological shield concrete
- Ⅶ.Controlled Blasting / Removal of biological shield concrete