Dismantling of Primary Circuit Components in the NPP Obrigheim - 13117

After finally shutting down the Nuclear Power Plant in Obrigheim in 2005, the consortium consisting of Babcock Noell GmbH and E.ON Anlagenservice GmbH received the order to dismantle the large primary circuit components in 2007. Within the scope of the 2. decommissioning approval the following large primary circuit components are dismantled: - 2 Steam generators; - 2 Reactor coolant pumps (RCP); - Reactor coolant line (RCL); - 1 Pressurizer (PRZ). The dismantling of the large components necessitated a new equipment air lock which was installed during the first decommissioning step. The order for dismantling also includes the repair and manufacturing of auxiliary handling equipment, the installation of auxiliary handling equipment, and accomplishing all disassembly works. The existing equipment air lock was dismantled and replaced by a new one consisting of the following components: - Transport platform; - Equipment air lock consisting of 5 modules and 2 lifting gates; - Assembly opening; - Platforms; - Transfer carriage. The new equipment lock can be used for the complete steam generator as well as for single components. The primary circuit components are disassembled in the following sub-steps: - Installation of lifting equipment for steam generator; - Sectioning of pipes and removing of the interfering edges; - Disassembly of steam generator 1 and steam generator 2 by use of lifting equipment; - Disassembly of pressurizer; - Disassembly of reactor coolant pump and reactor coolant line. As the steam generator is disassembled using a hydraulic lifting device, the load-bearing capacity of the main hoist of the reactor building crane does not have to be increased. The partners have successfully replaced the material lock to fulfil the decommissioning requirements and disassembled and dismantled all primary circuit components. The dismantling process was executed in-time. The material was sorted and ready for transportation and recycling.