Physical Properties Models for Simulation of Processes to Treat INEEL Tank Farm Waste: Thermodynamic Equilibrium

.........................................................................................................................................iii SUMMARY........................................................................................................................................... iv INTRODUCTION ................................................................................................................................. 1 Process Design At INEEL ................................................................................................................. 1 Role Of Modeling............................................................................................................................... 2 Thermodynamic Modeling of Non-Ideal Solutions......................................................................... 2 Brief Overview Of Pitzer Ion-Interaction Model ........................................................................................... 3 Electrolyte Nomenclature............................................................................................................................... 5 COMPARISON OF ENRTL AND PITZER MODELS .................................................................... 6 Single-Salt Systems ............................................................................................................................ 6 Multiple-Salt Systems........................................................................................................................ 6 ASSESSMENT OF THE PITZER ION-INTERACTION MODEL................................................. 7 Background ........................................................................................................................................ 7 Solubility ........................................................................................................................................................ 7 Association ..................................................................................................................................................... 7 Potential Benefits ........................................................................................................................................... 7 Concerns......................................................................................................................................................... 8 Preliminary Conclusion .................................................................................................................................. 8 Validation ........................................................................................................................................... 8 High Concentration ........................................................................................................................................ 8 Solid-Liquid Equilibrium ............................................................................................................................... 9 Chemical Equilibrium Association .............................................................................................................. 9 H2SO4......................................................................................................................................................... 9 HNO3........................................................................................................................................................ 10 VALIDATION OF ASPEN PLUS ..................................................................................................... 12 Binary Interaction Terms For Ions Of Unlike Sign (β, β, C) ............................................... 12 Mixing Terms (Ф, ψ) ....................................................................................................................... 13 CONCLUSIONS.................................................................................................................................. 14 Path Forward ................................................................................................................................... 15 Pitzer Model ................................................................................................................................................. 15 ASPEN Plus ................................................................................................................................................. 16 REFERENCES .................................................................................................................................... 17 APPENDIX A: STEAM REFORMING PROCESS STREAMS WHERE ACTIVITY COEFFICIENT MODELS MAY BE APPLICABLE...................................................................... 20 SBW Mixing Tank........................................................................................................................... 21 Feed Mixing Tank............................................................................................................................ 21 Spray Quench................................................................................................................................... 21 Submerged Bed /Packed Bed/CausticScrubber ............................................................................ 22 High Efficiency Mist Eliminator (HEME)..................................................................................... 22 Evaporator/Salt Dryer .................................................................................................................... 22 Acid Fractionator (Distillation Column) ....................................................................................... 23