Open AccessThermodynamic Modeling of Savannah River Evaporators
Author(s) -
C.F. Weber
Publication year - 2001
Language(s) - English
Resource type - Reports
DOI - 10.2172/788505
Subject(s) - thermodynamics , workbench , solubility , work (physics) , evaporator , activity coefficient , atmospheric temperature range , aluminosilicate , chemistry , materials science , environmental science , engineering , mechanical engineering , physics , aqueous solution , heat exchanger , biochemistry , visualization , catalysis
A thermodynamic model based on the code SOLGASMIX is developed to calculate phase equilibrium in evaporators and related tank wastes at the Savannah River Site (SRS). This model uses the Pitzer method to calculate activity coefficients, and many of the required Pitzer parameters have been determined in the course of this work. Principal chemical species in standard SRS simulant solutions are included, and the temperature range for most parameters has been extended above 100 C. The SOLGASMIX model and calculations using the code Geochemists Workbench are compared to actual solubility data including silicate, aluminate, and aluminosilicate solutions. In addition, SOLGASMIX model calculations are also compared to transient solubility data involving SRS simulant solutions. These comparisons indicate that the SOLGASMIX predictions closely match reliable data over the range of temperature and solution composition expected in the SRS evaporator and related tanks. Predictions using the Geochemists Workbench may be unreliable, due primarily to the use of an inaccurate activity coefficient model