CARBON TRANSPORT STUDIES FOR HELIUM COOLED HIGH TEMPERATURE REACTORS. Project DRAGON.

Technical Report · Fri Jul 01 00:00:00 EDT 1966

OSTI ID:4089428

Everett, M R; Kinsey, D V; Roemberg, E

This report presents a review of information on coolant chemistry which has arisen during the development of a helium cooled high temperature reactor by the OECD Dragon Project. A thorough study of the chemical compatibility of graphite operating at temperatures up to 1200 deg C had to be carried out, so that acceptable impurity levels for the helium coolant of a HTGC reactor could be defined. The review summarises the results of six years’ work and covers experimental as well as theoretical studies in the chemical, in-pore and mass transfer controlled regimes, applicable to the thermal corrosion of HTR graphites when exposed to volume parts per million impurity levels in a helium carrier. Deviations from the thermal graphite corrosion rates caused by catalytic effects arising from metallic impurities in the graphite and also the effects of radiation producing active species which might accelerate these reactions have been investigated. Factors controlling the rates of possible back-reactions of CO on catalytically active metal surfaces around 500 deg C in the primary circuit have also been investigated. The effect of these rates on the possible carbon transport mechanism in a reactor coolant has been studied. Application of data to the Dragon Reactor and proposed HTGC power reactor designs indicates that no significant problem should arise affecting the integrity of the reactor from the combined effects of water inleakage, core corrosion, irradiation effects, and carbon deposition, if a suitable balance between the extent of impurity inleakage and rate of coolant purification is maintained. (auth)

• Research Organization: Atomic Energy Establishment, Winfrith (England)
• NSA Number: NSA-25-003860
• OSTI ID: 4089428
• Report Number(s): DP-Report-491
• Resource Relation: Other Information: UNCL. Orig. Receipt Date: 31-DEC-71
• Country of Publication: United Kingdom
• Language: English

Related Subjects

N38140* -Power Reactor Development-Cooling Systems
N30210 -Metals
Ceramics
& Other Materials-Ceramics & Cermets-Corrosion & Erosion & Surface Phenomena
CORROSION
DRAGON
GAS COOLED REACTORS
GRAPHITE
HELIUM
IMPURITIES
POWER REACTORS
TESTING
GRAPHITE/corrosion of
effects of high temperature helium cooled reactor environment on
HIGH-TEMPERATURE GAS-COOLED REACTOR EXPERIMENT/core components for
corrosion of graphite
REACTORS
GAS-COOLED/core components of
corrosion of graphite
REACTORS
POWER/core components of helium cooled
corrosion of graphite