Published September 25, 1980 | Version v1
Patent Metadata-only

Process for solidifying radioactive residues containing boron

Creators

Description

Radioactive residues which occur in the operation of PWR's include boron in the form of borates, which are surrounded so as to be watertight by embedding in a binder, for example bitumen, using a mixing device. According to the invention, a mole ratio of sodium to boron of either 0.25 or 0.7 is set by adding caustic soda solution, corresponding to pH value ranges of 7.3 to 8.0 for a mole ratio of 0.25 and 9.8 to 10.2 for a mole ratio of 0.7. This produces optimum embedding without crystallization and a much better resistance to leaching. (orig./HP)

Availability note (English)

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

Abstract (German)

Radioaktive Rueckstaende beim Betrieb von DWR umfassen Bor in Form von Boraten, das durch Einbetten in Bindemittel, beispielsweise Bitumen, mit Hilfe einer Mischvorrichtung wasserdicht umschlossen wird. Erfindungsgemaess wird durch einen Zusatz von Natronlauge ein Molverhaeltnis Natrium zu Bor von entweder 0,25 oder 0,7 eingestellt, entsprechend pH-Wert-Bereichen von 7,3 bis 8,0 fuer ein Molverhaeltnis von 0,25 und 9,8 bis 10,2 fuer ein Molverhaeltnis von 0,7. Dies ergibt ohne Auskristallisieren eine optimale Einbettung und eine wesentlich verbesserte Auslaugbestaendigkeit. (orig./HP)

Additional details

Additional titles

Original title (German)
Verfahren zur Verfestigung von borhaltigen radioaktiven Rueckstaenden

Publishing Information

Imprint Pagination
7 p.
IPC:
Int. Cl. G21F 9/16.
IPC
Int. Cl. G21F 9/16.
Patent number
DE patent document 2910677/A/

INIS

Country of Publication
Germany
Country of Input or Organization
Germany
INIS RN
17047788
Subject category
S12: MANAGEMENT OF RADIOACTIVE WASTES, AND NON-RADIOACTIVE WASTES FROM NUCLEAR FACILITIES; S21: SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS;
Resource subtype / Literary indicator
Non-conventional Literature
Descriptors DEI
BITUMENS; BORATES; CEMENTS; EVAPORATION; LEACHING; LIQUID WASTES; MIXING; POLYMERS; PWR TYPE REACTORS; RADIOACTIVE WASTE PROCESSING; REACTOR OPERATION; SOLIDIFICATION; STABILITY
Descriptors DEC
BORON COMPOUNDS; BUILDING MATERIALS; DISSOLUTION; ENRICHED URANIUM REACTORS; MANAGEMENT; MATERIALS; OPERATION; ORGANIC COMPOUNDS; OTHER ORGANIC COMPOUNDS; OXYGEN COMPOUNDS; PHASE TRANSFORMATIONS; POWER REACTORS; REACTORS; SEPARATION PROCESSES; TAR; THERMAL REACTORS; WASTE MANAGEMENT; WASTE PROCESSING; WASTES; WATER COOLED REACTORS; WATER MODERATED REACTORS