TMI-2 (Three Mile Island Unit 2) core region defueling
In July of 1982, a video camera was inserted into the Three Mile Island Unit 2 reactor vessel providing the first visual evidence of core damage. This inspection, and numerous subsequent data acquisition tasks, revealed a central void /approx/1.5 m (5 ft) deep. This void region was surrounded by partial length fuel assemblies and ringed on the periphery by /approx/40 full-length, but partial cross-section, fuel assemblies. All of the original 177 fuel assemblies exhibited signs of damage. The bottom of the void cavity was covered with a bed of granular rubble, fuel assembly upper end fittings, control rod spiders, fuel rod fragments, and fuel pellets. It was obvious that the normal plant refueling system not suitable for removing the damaged core. A new system of defueling tools and equipment was necessary to perform this task. Design of the new system was started immediately, followed by >1 yr of fabrication. Delivery and checkout of the defueling system occurred in mid-1985. Actual defueling was initiated in late 1985 with removal of the debris bed at the bottom of the core void. Obstructions to the debris, such as end fittings and fuel rod fragments ere removed first; then /approx/23,000 kg (50,000lb) of granular debris was quickly loaded into canisters. Core region defueling was completed in late 1987, /approx/2 yr after it was initiated.
- OSTI ID:
- 5619093
- Report Number(s):
- CONF-881011-
- Journal Information:
- Trans. Am. Nucl. Soc.; (United States), Journal Name: Trans. Am. Nucl. Soc.; (United States) Vol. 57; ISSN TANSA
- Country of Publication:
- United States
- Language:
- English
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22 GENERAL STUDIES OF NUCLEAR REACTORS
220900* -- Nuclear Reactor Technology-- Reactor Safety
ACCIDENTS
BOREHOLES
CAMERAS
CAVITIES
CHEMISTRY
COAGULANTS
CONTAINERS
CONTROL ELEMENTS
CORIUM
DAMAGE
DATA ACQUISITION
DEMOLITION
DRILLING EQUIPMENT
DRUGS
ENRICHED URANIUM REACTORS
EQUIPMENT
FILTERS
FLUID MECHANICS
FUEL ASSEMBLIES
FUEL ELEMENTS
HEMATOLOGIC AGENTS
HYDRAULICS
HYDROGEN COMPOUNDS
HYDROGEN PEROXIDE
INORGANIC COMPOUNDS
INSPECTION
LEAKS
MECHANICAL STRUCTURES
MECHANICS
MELTDOWN
MICROORGANISMS
NATIONAL ORGANIZATIONS
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OXYGEN COMPOUNDS
PERFORMANCE
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PRESSURE VESSELS
PRODUCTIVITY
PWR TYPE REACTORS
REACTOR ACCIDENTS
REACTOR COMPONENTS
REACTOR CORE DISRUPTION
REACTOR DISMANTLING
REACTORS
SAMPLING
SCHEDULES
SUPPORTS
TELEVISION CAMERAS
THERMAL REACTORS
THREE MILE ISLAND-2 REACTOR
TOOLS
US DOE
US ORGANIZATIONS
WATER CHEMISTRY
WATER COOLED REACTORS
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