Robotic design features can reduce cavity contamination levels by up to 80 percent.
The Challenge
Decontaminating the reactor cavity traditionally involves manual scrubbing and vacuuming, which not only subjects personnel to extremely high-dose areas but prohibits them from accessing select areas entirely. Exelon challenged our outage teams to develop a remote decontamination system that would reduce both personnel dose exposure and critical path schedule duration.
Our Solution
Using innovative tooling, we developed a remote robotic system to further enhance our reactor cavity cleaning system. The submersible delivery platform is outfitted with several design features that can scrub and vacuum both horizontal and vertical surfaces to ensure safe and efficient cleaning and decontamination.
The robotic crawler leverages adjustable ballast technology to provide precise depth control, allowing the submersible to navigate complex reactor cavity environments. Once it reaches the remote area, a rotating scrub brush is used to loosen contamination as well as a ventral vacuum port to remove any loosened deposits and foreign objects. The delivery platform also carries three tilting video cameras with integrated illumination to monitor cleaning services. The cleaning system is controlled from a remote location using a six-monitor station with audio and visual recording.
The Impact
The deployment of our enhanced cavity cleaning system at LaSalle County Generating Station removed 80 REM per hour of contamination and identified multiple foreign objects. The remote capabilities resulted in a reduced dose to personnel when entering the cavity post-drain down and provided access to previously unreachable areas.
Key Statistics
- Robotic design features reduced cavity contamination levels by 80 percent
- Removed 80 REM per hour of contamination and identified multiple foreign objects
- Cleaning was performed in parallel with other refueling activities to minimize schedule impact
