Hp. Gros et al., NEAR-CRITICAL SEPARATION OF AQUEOUS AZEOTROPIC MIXTURES - PROCESS SYNTHESIS AND OPTIMIZATION, The Journal of supercritical fluids, 12(1), 1998, pp. 69-84
The near critical extraction of alcohols from aqueous solutions is add
ressed, combining reliable thermodynamic models with robust simulation
and optimization methods. Based on the process key phase equilibrium
properties, a methodology for process optimization is proposed and ill
ustrated for the extraction of ethanol using near-critical propane as
solvent. Several process schemes are evaluated. (i) conventional heati
ng, (ii) vapor recompression, and (iii) feed preconcentration. The opt
imal schemes and conditions for this separation problem are obtained.
The process constraints are determined and removed through structural
modifications of the process. The effect of the process constraints on
economics and operating conditions is analyzed. The methodology resul
ts in a general process flowsheet for the near-critical separation of
aqueous azeotropic mixtures. (C) 1998 Elsevier Science B.V.