Development Of A Software For Simulating Separation Processes Using A Nonequilibrium Stage Model

This paper is concerned with the computational aspects of countercurrent multicomponent separation processes using a nonequilibrium stage model. The developed program solves the component material and energy balance relations for each phase together with mass and energy transfer rate equations and equilibrium equations for the interface. The program is formulated in such a way as to make the describing equations and the method of solving them independent of the methods used to predict the vapor and liquid multicomponent mass transfer coefficients and heat transfer coefficients as well as physical properties like density, viscosity, binary diffusion coefficients. component specific heats and thermal conductivity, and the thermodynamic properties of the system. The composition and temperature profiles predicted by the program during the multicomponent distillation in bubble-cap-tray columns can be compared with the profiles given by the simulation using a conventional equilibrium stage model The comparison permits the deduction of a methodology to predict more realistic stage efficiencies which can allow the utilization of the equilibrium stage model. A first attempt is being made using a new procedure based on the O'Connell correlation.20SUPPL.1S279S284Barros, A.A.C., (1995), PhD Thesis, LDPS, DPQ, FEQ, UNICAMP, BRASILGardner, R.G., McLean, A.Y., Effect of System Properties on Sieve-plate Froths (1969) I. Chem. Eng. Symposium Series, pp. 39-48. , Proceedings of the International Symposium on Distillation 1969. Brighton, England, Session 2King, C.J., (1980) Separation Processes, , McGraw-Hill, New York, 2nd editionKrishna, R., Standart, G.L., A Multicomponent Film Model Incorporating a General Matrix Method of Solution to the Maxwell-Stefan Equations (1976) AIChE Journal, 22 (2), pp. 383-388Krishnamurthy, R., Taylor, R., A Nonequilibrium Stage Model of Multicomponent Separation Processes - Part I: Model description and Method of solution (1985) AIChE Journal, 31 (3), pp. 449-456Krishnamurthy, R., Taylor, R., A Nonequilibrium Stage Model of Multicomponent Separation Processes - Part II: Comparison with experiment (1985) AIChE Journal, 31 (3), pp. 456-465Krishnamurthy, R., Taylor, R., A Nonequilibrium Stage Model of Multicomponent Separation Processes - Part III: The Influence of Unequal Component Efficiencies in Process Design Problems (1985) AIChE Journal, 31 (12), pp. 1973-1985Naphtali, L.M., Sandholm, D.P., Multicomponent Separation Calculations by Linearization (1971) AIChE Journal, 17 (1), pp. 148-153O'Connell, H.E., Plate Efficiency of Fractionating Columns and Absorbers (1946) Trans. Am. Inst. Chem. Eng., 42, pp. 741-755Reid, R.C., Prausnitz, J.M., Poling, B.E., (1988) The Properties of Gases and Liquids, 4th Edition, , McGraw Hil