A Steady State Model for Describing the Phosphate Lattice Loss

A steady-state model for the industrial dihydrate phosphoric acid plant is developed. It is based upon material and balance equations and fundamental treatment of thermodynamics. The thermodynamic model includes the main species that are present in the aqueous phase of wet phosphoric acid process. For comparison, the electrolyte – NRTL model was used for describing the activity coefficients of the species in the aqueous solution. The model was validated by comparing its phosphate lattice loss prediction to data reported by Janikowski et al. [1] and Abutayeh and Campbell, [2] for Moroccan phosphate rock. A developed model was used to simulate the dihydrate process with the aim of quantifying the thermodynamically–controlled phosphate lattice loss. The obtained results by Electrolyte – NRTL model were in agreement with those obtained by Abutayeh and Campbell [2] that use the Edwards–Maurer– Newman–Prausnitz Pitzer model to describe the activity coefficient of the aqueous species present in the wet phosphoric acid process.