Behavior of highly radioactive iodine on charcoal in moist air

Conference · Thu Jan 01 04:00:00 EST 1976

OSTI ID:7357793

Lorenz, R A; Manning, S R; Martin, W J

The behavior of highly radioactive iodine adsorbed on charcoal exposed to moist air (110 torr water vapor partial pressure) was investigated in a series of six experiments. The amount of radioactive /sup 130/I on the well-insulated 28-cm/sup 3/ bed ranged from 50 to 570 Ci, and the relative humidity was 47 percent at the bed inlet temperature of 70/sup 0/C. Radioactive iodine was released from the test beds at a continuous fractional release rate of approximately 7 x 10/sup -6//hr for all types of charcoal tested. The chemical form of the released iodine was such that it was very highly penetrating with respect to the nine different types of commercial impregnated charcoals tested in backup collection beds. Two types of silver-nitrate-coated adsorption materials behaved similarly to the charcoals. Silver-exchanged type 13-X molecular sieve adsorbers were 20 to 50 times more efficient for adsorbing the highly penetrating iodine, but not as efficient as normally found for collecting methyl iodide. The chemical form of the highly penetrating iodine was not determined. When the moist air velocity was decreased from 28.5 fpm (25/sup 0/C) to as low as 0.71 fpm (25/sup 0/C), the charcoal bed temperature rose slowly and reached the ignition temperature in three of the experiments. At 0.71 fpm (25/sup 0/C) the ignited charcoal beds reached maximum temperatures of 430 to 470/sup 0/C because of the limited oxygen supply. The charcoal exposed for four years at Oak Ridge ignited at 283/sup 0/C compared with 368/sup 0/C for unused charcoal from the same batch. Two of the experiments used charcoal containing 1 or 2 percent TEDA (triethylene-diamine) and a proprietary flame retardant. The oxidation and ignition behavior of these charcoals did not appear to be affected adversely by the presence of the TEDA.

• Research Organization: Oak Ridge National Lab., Tenn. (USA)
• DOE Contract Number: W-7405-ENG-26
• OSTI ID: 7357793
• Report Number(s): CONF-760822-9(DRAFT)
• Country of Publication: United States
• Language: English

Related Subjects

052001* -- Nuclear Fuels-- Waste Processing
12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE WASTES FROM NUCLEAR FACILITIES
ADSORBENTS
ADSORPTION
AIR
AIR FILTERS
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
CHARCOAL
EQUIPMENT
FILTERS
FLUIDS
GASES
HOURS LIVING RADIOISOTOPES
IGNITION
INTERMEDIATE MASS NUCLEI
IODINE 130
IODINE ISOTOPES
ISOTOPES
MANAGEMENT
MOLECULAR SIEVES
NUCLEAR FACILITIES
NUCLEI
ODD-ODD NUCLEI
POLLUTION CONTROL EQUIPMENT
PROCESSING
RADIOACTIVE WASTE PROCESSING
RADIOISOTOPES
SORPTION
SORPTIVE PROPERTIES
SURFACE PROPERTIES
WASTE MANAGEMENT
WASTE PROCESSING