Steady-State Simulation of Steam Reforming of INEEL Tank Farm Waste

Nichols, T.T. ; Taylor, D.D. ; Wood, R.A. ; Barnes, C.M.

Idaho National Engineering and Environmental Laboratory

关键词: Mass Balance;    Off-Gas;    Thermodynamic Activity;    Wastes Sodium-Bearing Waste;    Storage Facilities;   

DOI  :  10.2172/801031
RP-ID  :  INEEL/EXT-02-01052
RP-ID  :  AC07-99ID13727
RP-ID  :  801031

美国|英语

来源: UNT Digital Library

【 摘 要 】

A steady-state model of the Sodium-Bearing Waste steam reforming process at the Idaho National Engineering and Environmental Laboratory has been performed using the commercial ASPEN Plus process simulator. The preliminary process configuration and its representation in ASPEN are described. As assessment of the capability of the model to mechanistically predict product stream compositions was made, and fidelity gaps and opportunities for model enhancement were identified, resulting in the following conclusions: (1) Appreciable benefit is derived from using an activity coefficient model for electrolyte solution thermodynamics rather than assuming ideality (unity assumed for all activity coefficients). The concentrations of fifteen percent of the species present in the primary output stream were changed by more than 50%, relative to Electrolyte NRTL, when ideality was assumed; (2) The current baseline model provides a good start for estimating mass balances and performing integrated process optimization because it contains several key species, uses a mechanistic electrolyte thermodynamic model, and is based on a reasonable process configuration; and (3) Appreciable improvement to model fidelity can be realized by expanding the species list and the list of chemical and phase transformations. A path forward is proposed focusing on the use of an improved electrolyte thermodynamic property method, addition of chemical and phase transformations for key species currently absent from the model, and the combination of RGibbs and Flash blocks to simulate simultaneous phase and chemical equilibria in the off-gas treatment train.