Verification of Site Cleanup Using a Dual-Equilibrium Desorption Model

Post test calculations with the accident codes COCOSYS-AIM and ASTEC-IODE were performed on the iodine multi-compartment tests of the German ThAI program (Thermal hydraulics, Aerosols, Iodine). In the tests transport and adsorption/desorption behavior of gaseous I2 were measured in the 60 m3 vessel with a five-compartment configuration under severe accident conditions. The thermal hydraulic modules in COCOSYS and in the containment part of ASTEC (CPA) are nearly identical but not the iodine modules AIM and IODE. The adsorption/desorption model in AIM is based on ThAI data whereas in IODE correlations derived from laboratory-scale tests are used. A 50-zone nodalisation of the ThAI vessel was used with both codes. COCOSYS-AIM and ASTEC-IODE describe qualitatively correctly the I2 concentration differences of several orders of magnitude in periods with stratified atmosphere and the slow homogenization in a convective mixed atmosphere. However, both codes overestimate the gaseous I2 concentration at high relative humidity. The most likely reason is a slow reaction of deposited I2 to the non-volatile FeI2 on the steel surfaces, which has not been modeled sufficiently yet. Further experimental investigations in the ThAI facility are envisaged. A considering of the ThAI data in the I2 adsorption/desorption correlations may improve future ASTEC-IODE results. Nevertheless, the analyses of the large-scale ThAI iodine tests have been an important validation step for COCOSYS-AIM and ASTEC-IODE demonstrating the capability of multi-compartment I2 treatment.

Download Full-text

EVIDENCE OF AN ADSORPTION-DESORPTION MODEL FOR HUMAN IRRITANT PERCEPTION

Journal of Sensory Studies ◽

10.1111/j.1745-459x.1994.tb00247.x ◽

1994 ◽

Vol 9 (3) ◽

pp. 273-291 ◽

Cited By ~ 4

Author(s):

MARGARET A. CLIFF ◽

HILDEGARDE HEYMANN

Keyword(s):

Adsorption Desorption ◽

Desorption Model

Download Full-text

LAJU ADSORPSI DAN DESORPSI PARAQUAT PADA TANAH PERTANIAN DESA OESAO KECAMATAN KUPANG TIMUR

Molekul ◽

10.20884/1.jm.2010.5.1.70 ◽

2010 ◽

Vol 5 (1) ◽

pp. 1

Author(s):

Sherlly M.F. Ledoh ◽

Hermania Em Wogo ◽

Siti Arianti S.A

Keyword(s):

Ammonium Chloride ◽

Relative Stability ◽

Sea Water ◽

Natural State ◽

Desorption Rate ◽

Kinetic Adsorption ◽

Saturated State ◽

Before And After ◽

Desorption Model

The research about determination of kinetic adsorption and desorption rate of paraquat on agriculture area Oesao-east Kupang has been done. The aim of this research was to determine the kinetic of paraquat adsorption before and after saturated and to model the desorption. The research consisted of evaluation of the analitycal procedure for paraquat, pattern of soil kinetic adsorption and paraquat desorption. The result of procedure evaluation showed that reduced paraquat absorbed at λ maximum 606 nm and relative stability at 0-150 minutes. Constant of paraquat kinetic adsorption at natural state bigger than saturated state. k1 value at natural state was 0,011 per minute whereas k1 value at saturated state was 0,003 per minute. Desorption model of paraquat by using three desorbents were ammonium chloride, 29,2% of sea water salinity and aquadest showed the best desorbent was ammonium chloride, followed by sea water and aquadest.

Download Full-text