skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Computational analysis of coupled fluid, heat, and mass transport in ferrocyanide single-shell tanks: FY 1994 interim report. Ferrocyanide Tank Safety Project

Technical Report ·
DOI:https://doi.org/10.2172/10196821· OSTI ID:10196821

A computer modeling study was conducted to determine whether natural convection processes in single-shell tanks containing ferrocyanide wastes could generate localized precipitation zones that significantly concentrate the major heat-generating radionuclide, {sup 137}Cs. A computer code was developed that simulates coupled fluid, heat, and single-species mass transport on a regular, orthogonal finite-difference grid. The analysis showed that development of a ``hot spot`` is critically dependent on the temperature dependence for the solubility of Cs{sub 2}NiFe(CN){sub 6} or CsNaNiFe(CN){sub 6}. For the normal case, where solubility increases with increasing temperature, the net effect of fluid flow, heat, and mass transport is to disperse any local zones of high heat generation rate. As a result, hot spots cannot physically develop for this case. However, assuming a retrograde solubility dependence, the simulations indicate the formation of localized deposition zones that concentrate the {sup 137}Cs near the bottom center of the tank where the temperatures are highest. Recent experimental studies suggest that Cs{sub 2}NiFe(CN){sub 6}(c) does not exhibit retrograde solubility over the temperature range 25{degree}C to 90{degree}C and NaOH concentrations to 5 M. Assuming these preliminary results are confirmed, no natural mass transport process exists for generating a hot spot in the ferrocyanide single-shell tanks.

Research Organization:
Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
Sponsoring Organization:
USDOE, Washington, DC (United States)
DOE Contract Number:
AC06-76RL01830
OSTI ID:
10196821
Report Number(s):
PNL-10163; ON: DE95004226
Resource Relation:
Other Information: PBD: Nov 1994
Country of Publication:
United States
Language:
English