Reliable computation of phase stability using interval analysis : Cubic equation of state models

The reliable prediction of phase stability is a challenging computational problem in chemical process simulation, optimization and design. The phase stability problem can be formulated either as a minimization problem or as an equivalent nonlinear equation solving problem. Conventional solution methods are initialization dependent, and may fail by converging to trivial or non-physical solutions or to a point that is a local but not global minimum. Thus there has been considerable recent interest in developing more reliable techniques for stability analysis. In this paper we demonstrate, using cubic equation of state models, a technique that can solve the phase stability problem with complete reliability. The technique, which is based on interval analysis, is initialization independent, and if properly implemented provides a mathematical guarantee that the correct solution to the phase stability problem has been found.

[1]  Global Stability Analysis and Calculation of Liquid−Liquid Equilibrium in Multicomponent Mixtures† , 1996 .

[2]  Christodoulos A. Floudas,et al.  Global optimization for the phase stability problem , 1995 .

[3]  K. Kobe The properties of gases and liquids , 1959 .

[4]  Christodoulos A. Floudas,et al.  Global Optimization and Analysis for the Gibbs Free Energy Function Using the UNIFAC, Wilson, and ASOG Equations , 1995 .

[5]  M. Michelsen The isothermal flash problem. Part I. Stability , 1982 .

[6]  C. Floudas,et al.  GLOPEQ: A new computational tool for the phase and chemical equilibrium problem , 1997 .

[7]  J. D. Seader,et al.  Application of interval Newton's method to chemical engineering problems , 1995, Reliab. Comput..

[8]  E. Hansen,et al.  Bounding solutions of systems of equations using interval analysis , 1981 .

[9]  Wallace B. Whiting,et al.  Area method for prediction of fluid-phase equilibria , 1992 .

[10]  The fractal response of robust solution techniques to the stationary point problem , 1993 .

[11]  R. Baker Kearfott,et al.  Algorithm 681: INTBIS, a portable interval Newton/bisection package , 1990, TOMS.

[12]  L. E. Baker,et al.  Gibbs energy analysis of phase equilibria , 1982 .

[13]  M. Stadtherr,et al.  Robust process simulation using interval methods , 1996 .

[14]  Chenyi Hu,et al.  Algorithm 737: INTLIB—a portable Fortran 77 interval standard-function library , 1994, TOMS.

[15]  Mark A. Stadtherr,et al.  ROBUST PHASE STABILITY ANALYSIS USING INTERVAL METHODS , 1998 .

[16]  C. Floudas,et al.  Global optimization for the phase and chemical equilibrium problem: Application to the NRTL equation , 1995 .

[17]  Eldon Hansen,et al.  Global optimization using interval analysis , 1992, Pure and applied mathematics.

[18]  R. B. Kearfott Rigorous Global Search: Continuous Problems , 1996 .

[19]  Mark A. Stadtherr,et al.  Reliable prediction of phase stability using an interval Newton method , 1996 .

[20]  M. Mongeau,et al.  Global Optimization for the Chemical and Phase Equilibrium Problem using Interval Analysis , 1996 .

[21]  A. Neumaier Interval methods for systems of equations , 1990 .

[22]  W. Seider,et al.  Homotopy-continuation method for stability analysis in the global minimization of the Gibbs free energy , 1995 .

[23]  A. S. Cullick,et al.  New strategy for phase equilibrium and critical point calculations by thermodynamic energy analysis. Part I. Stability analysis and flash , 1991 .