Development and Deployment of the In-Tank Remote Viewing System for the ORNL Melton Valley Storage Tanks Facility

摘要

A remote viewing system was needed for in-tank inspection at the ORNL Melton Valley Storage Tanks (MVST). ORNL has 8 tanks at the MVST facility that are used to store Liquid Low-Level Waste (LLLW) prior to processing in the TRU/Alpha waste treatment facility. Each tank has the capacity to store 50,000 gallons of liquid and sludge waste. The remote viewing system was needed to inspect tank conditions and to allow estimation of the volume of waste in the tanks prior to retrieval operations. The volume estimates utilized known fiducial markers internal to the tanks. The viewing system would have to penetrate a 3 inch riser to enter the tanks which are 61.5 feet long and 12 feet in diameter. The inspection required a remotely operated manipulator arm for deployment and a remotely operated viewing and lighting system. The manipulator arm would be required to penetrate the 3 inch riser which is 9.6 feet in length and then position the remote viewing system around occlusions in the tank (vertical risers) in the limited vapor space at the top of each tank. The inspection system was deployed in the MVST tanks during July and August of 2001. This paper discusses the design, fabrication, and deployment of the system.