In-situ verification techniques for fast critical assembly cores

Conference · Mon Jan 01 00:00:00 EST 1979

OSTI ID:5536585

Brumbach, S. B.; Amundson, P. I.; Roche, C. T.

Active and passive autoradiographic techniques were used to obtain piece counts of fuel plates in fast critical assembly drawers and to verify the assembly loading pattern. Active autoradiography using prompt-fission and fission-product radiation was more successful with uranium fuel while passive autoradiography was more successful with plutonium fuel. A source multiplication technique was used to measure changes in reactivity when small quantities (2-2.5 kg) of fissile material were removed from a subcritical reference core of the Zero Power Plutonium Reactor. Efforts to compensate for unsuccessful. Some compensation was achieved by replacing U-238 with polyethylene. The sensitivity for detection of partially compensated fuel removed from minimum worth regions was approximately 2.5 kg (fissile) for a core containing 2600 kg (fissile). Substitution of polyethylene was detected with a spectral index which was the ratio of the rate of the In-115 (n,..gamma..) reaction to the rate of the In-115 (n,n') reaction. This spectral index was sensitive to the presence of an 0.64-cm-thick, 5.08-cm-high polyethylene column 10-15 cm away from the indium foil. The reactivity worth of Pu-239 was also obtained as a function of location in the reactor core with the use of an inverse kinetics technique. Reactivity worths for Pu-239 varied from a maximum of 58.67 Ih/kg near the core center to a minimum of 14.86 Ih/kg at the core edge.

• Research Organization: Argonne National Lab., IL (USA)
• DOE Contract Number: W-31-109-ENG-38
• OSTI ID: 5536585
• Report Number(s): CONF-791117-20; TRN: 80-004435
• Resource Relation: Conference: ANS topical conference, Kiawah Island, SC, USA, 26 Nov 1979
• Country of Publication: United States
• Language: English

Related Subjects

98 NUCLEAR DISARMAMENT, SAFEGUARDS, AND PHYSICAL PROTECTION
37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
FUEL PLATES
INVENTORIES
ZERO POWER REACTORS
SAFEGUARDS
ZPPR REACTOR
AUTORADIOGRAPHY
FAST REACTORS
FISSILE MATERIALS
INDIUM 115
NEUTRON REACTIONS
PLUTONIUM 239
POLYETHYLENES
REACTIVITY WORTHS
REACTOR KINETICS
ACTINIDE ISOTOPES
ACTINIDE NUCLEI
ALPHA DECAY RADIOISOTOPES
BARYON REACTIONS
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
EPITHERMAL REACTORS
EVEN-ODD NUCLEI
EXPERIMENTAL REACTORS
FISSIONABLE MATERIALS
FUEL ELEMENTS
HADRON REACTIONS
HEAVY NUCLEI
HOURS LIVING RADIOISOTOPES
INDIUM ISOTOPES
INTERMEDIATE MASS NUCLEI
INTERNAL CONVERSION RADIOISOTOPES
ISOMERIC TRANSITION ISOTOPES
ISOTOPES
KINETICS
NUCLEAR REACTIONS
NUCLEI
NUCLEON REACTIONS
ODD-EVEN NUCLEI
ORGANIC COMPOUNDS
ORGANIC POLYMERS
PLUTONIUM ISOTOPES
POLYMERS
POLYOLEFINS
RADIOISOTOPES
REACTOR COMPONENTS
REACTORS
RESEARCH AND TEST REACTORS
RESEARCH REACTORS
YEARS LIVING RADIOISOTOPES
055001* - Nuclear Fuels- Safeguards
Inspection
& Accountability- Technical Aspects
400103 - Radiometric & Radiochemical Procedures- (-1987)