Refueling flexibility of the THTR-300 after shut-down periods

Conference · Wed Jan 01 04:00:00 EST 1975 · Atomkernenergie, v. 25, no. 2, pp. 133-136

OSTI ID:4130653

Gutsch, U; Patscher, W

The design of the THTR-pebble bed reactor is based on the thorium- uranium fuel cycle with continuous refueling. Under steady operating conditions the core is in an equilibrium state with stationary isotopic densities. During an extended shut-down period, however, the protactinium, which is bred from thorium, decays into fissile U 233. This decay produces an excess reactivity, which after restarting reduces relatively slowly during the normal refueling. This can be used to obtain a greater flexibility in the refueling strategy. It will be shown, that the reactor after a shut-down period can be operated for several days or weeks with reduced or without any fueling. Such modifications of the fueling mode have no serious consequences on the axial core composition or the reactivity behavoiur after the restart of fueling. In addition the modified fueling strategies are not expected to result in higher temperatures for the fuel elements. This can be used to start the reactor up again after a shut-down period, even if the refueling circulating system is not yet available or only available for limited periods. (orig.)

• Research Organization: Hochtemperatur-Reaktorbau G.m.b.H., Mannheim (F.R. Germany)
• NSA Number: NSA-33-011237
• OSTI ID: 4130653
• Conference Information: Journal Name: Atomkernenergie, v. 25, no. 2, pp. 133-136
• Country of Publication: Germany
• Language: German

Related Subjects

*THTR-300 REACTOR-- REACTOR FUELING
210300* --Nuclear Power Plants--Power Reactors
Non- Breeding
Graphite Moderated
FUEL MANAGEMENT
N77300* --Reactors--Power Reactors
Non-breeding
Graphite Moderated
REACTOR OPERATION
REACTOR SHUTDOWN