MODELING OF SOLID PRECIPITATION FROM RESERVOIR FLUID

A solid precipitation model is proposed for liquid-solid equilibrium b ased on the Flory-Huggins polymer solution theory along with a modific ation to account for the colloidal suspension effect of partial solubl e solid compounds in the fluid mixture. The colloidal effect is depend ent on the estimation of the critical resins concentration. A linear v ariation of free volume is assumed in terms of the component molecular weight for the evaluation of volume fraction in the polymer solution formulation. The binary interaction energy coefficient is introduced t o allow for positive or negative deviation from the ideal solution. Th e effect of heat capacity difference between the liquid and solid phas es and the effect of pressure correction are included in the model. Ne w correlations have also been developed for the model. A multimodel mu ltiphase flash algorithm is formulated using an equation of state for vapour-liquid equilibrium and the proposed model for liquid-solid equi librium. A detailed discussion of the model performance and the effect of the model parameters on the fitting to experimental results are al so presented.