Published December 10, 1987 | Version v1
Patent

Overheat protection for nuclear reactors

Description

Above the combustion chamber of a graphite-moderated reactor, there are chambers containing neutron-absorbing material connected to the combustion chamber via down pipes closed by means of slide valves. The material is composed of a granulate and gas-forming materials which together are bound to pellets in a cement matrix. The granulate consisting of neutron-absorbing material contains 38-50% by weight of silicon oxide, 10-20% by weight of sodium oxide, 5-20% by weight of gadolinium oxide (Gd203), 5-10% by weight boron oxide (B203) and up to 5% by weight of magnesium oxide (MgO); it is included in the formers in a volume of 60-75% by weight, the cement fraction, e.g. portland cement 35 F, having 20-35% by weight of water, as well as 5-8% by weight of water (in a water-cement ratio of 0.15-0.22). (The total quantity constitutes the point of reference for each of these figures.) (orig./DG)

Availability note (English)

Available from Deutsches Patentamt, Muenchen (Germany, F.R.).

Abstract (German)

Ueber der Brennkammer eines graphitmoderierten Reaktors sind neutronenabsorbierendes Material enthaltende Kammern vorgesehen, die mit der Brennkammer mittels durch Schieber verschlossener Fallrohrleitungen verbunden sind. Das Material ist von einem Granulat und glasbildenden Materialien gebildet, die gemeinschaftlich in einer Zementmatrix zu Pellets gebunden sind. Das Granulat aus neutronenabsorbierendem Material enthaelt 38-50 Gew.-% Siliziumdioxid, 10-20 Gew.-% Natriumoxid, 5-20 Gew.-% Gadoliniumoxid (Gd203), 5-10 Gew.-% Boroxid (B203) sowie bis zu 5 Gew.-% Magnesiumoxid (MgO) und ist in den Formkoerpern in einer Menge von 60-75 Gew.-% bei einem Zementanteil von 20-35 Gew.-%, beispielsweise Portlandzement 35 F, sowie 5-8 Gew.-% Wasser (Wasser/Zement-Verhaeltnis 0,15-0,22) - jeweils bezogen auf die Gesamtmenge - enthalten. (orig./DG)

Additional details

Additional titles

Original title (German)
Anordnung zur Sicherung der Brennkammer von Kernreaktoren gegen Ueberhitzung

Publishing Information

Imprint Pagination
3 p.
IPC:
Int. Cl. G21C 9/02; G21C 7/06; C04B 28/02; C04B 14/06; C04B 14/30; C04B 14/34; C03C 3/089.
IPC
Int. Cl. G21C 9/02; G21C 7/06; C04B 28/02; C04B 14/06; C04B 14/30; C04B 14/34; C03C 3/089.
Patent number
DE patent document 3618966/A1/

INIS

Country of Publication
Germany
Country of Input or Organization
Germany
INIS RN
21007952
Subject category
S21: SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS;
Resource subtype / Literary indicator
Non-conventional Literature
Descriptors DEI
GRAPHITE MODERATED REACTORS; NEUTRON ABSORBERS; NUCLEAR POWER PLANTS; OXIDES; REACTOR ACCIDENTS; REACTOR PROTECTION SYSTEMS; SCRAM
Descriptors DEC
ACCIDENTS; CHALCOGENIDES; NUCLEAR FACILITIES; OXYGEN COMPOUNDS; POWER PLANTS; REACTOR SHUTDOWN; REACTORS; SHUTDOWN; THERMAL POWER PLANTS