LIQUID METAL FUEL REACTOR EXPERIMENT--CRITICAL EXPERIMENT. Final Hazards Evaluation
The LMFRE is described briefly. It is a graphite moderated, graphite reflected reactor, using as fuel a circulating solution of U/sup 235/ in liquid bismuth, which transports heat to an external heat rejection system. The critical experiment program is outlined. The basic information to be obtained is the critical size and concentration of a series of assemblies in which the uranium concentration snd reflector thickness are varied. Control rod experiments are planned, as well as test hole effects, and effects of fuel in the reflectors and plenums. The critical sssembly is constructed in two halves, one each on a movable and stationary table. The core is constucted of several thousand bars of bismuth and graphite, and fullyenriched U-Al alloy strips, held together in graphite channels. The reflector is built of large blocks of graphite. The table drive system and supporting structure, control rods and drives, neutron source and drive, and instrumentation are discussed. The storage and assembling of fuel, approach to critical, and operating procedures conform to standard practice. At least two large safety rods are cocked in each assembly for fast acting safety. Ultimate shutdown is provided by table separation. A fundamental reactivity addition rate limitation is 0.0005/sec, which applies to both control rod and table movement. Various accidents are discussed. The maximum credible accident is defined in terms of a loading error combined with failures in the safety circuits and thble drive mechanism and leads to a reactivity addition of 0.0015/sec up to 2% total excess reactivity. The ultimate shutdown mechanism is a combination of fuel boiling and graphite heating. Over a range of step reactivity additions up to 2% and ramps up to 2%sec, and for various conditions of heat transfer, the maximum possible energy release to terminate the excursion is l7OMw-sec. The environmental hazard due to 10% release of the fission product activity generated in the excursion is considered. The maximum dose to the nearest permanent resident, located 2500 ft from the laboratory, in no case represents a serious hazard. (auth)
- Research Organization:
- Babcock and Wilcox Co. Atomic Energy Div., Lynchburg, Va.
- DOE Contract Number:
- AT(30-1)-1940
- NSA Number:
- NSA-12-015828
- OSTI ID:
- 4321083
- Report Number(s):
- BAW-1049-1
- Resource Relation:
- Other Information: Orig. Receipt Date: 31-DEC-58
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
ACCIDENTS
ALUMINUM ALLOYS
BISMUTH
BLANKETS
BOILING
CIRCUITS
CONFIGURATION
CONTAMINATION
CONTROL ELEMENTS
COOLANT LOOPS
CRITICAL ASSEMBLIES
CRITICALITY
DENSITY
ENRICHMENT
ENVIRONMENT
EXCURSIONS
FAILURES
FISSION PRODUCTS
GRAPHITE
GRAPHITE MODERATOR
HEAT EXCHANGERS
HEAT TRANSFER
HEATING
HIGH TEMPERATURE
INSTRUMENTS
LIQUID FLOW
LIQUID METAL FUEL
LMFR
MASS
MEASURED VALUES
MECHANICAL STRUCTURES
MONITORING
MOTORS
NEUTRON SOURCES
PERFORMANCE
PLANNING
POPULATIONS
RADIATION DOSES
RADIOACTIVITY
REACTIVITY
REACTOR CORE
REACTOR FUELING
REACTOR SAFETY
REFLECTION
REFLECTORS
RODS
SERVOMECHANISMS
SHUTDOWN