B. Bolio, I. Quesada and I. E. Grossmann


Screen Shots:
Initial screen
Data input
Data Input:
Data interactive input
Data file

GLOBSEP is a computer interface designed for the application of the model developed by I.Quesada and I.E. Grossmann (1993) for the global optimization of separation processes with a single feed and mixed products. A single feed with N components must be separated into Kknown multicomponent product streams. Sharp separators and bypasses are used for this purpose.

The algorithm implemented in GLOBSEP is basically an interactive branch and bound which finds the minimum cost of separating the feed components into the final products. The model involves solving at the root node a LP to define the lower bound and a NLP for the upper bound. After the first iteration, a LP is solved at each subsequent node and an optional NLP for updating the upper bound.
The following assumptions are considered:

  • The objective function is a linear function of the total inlet flow to each separator

  • Components are ordered from lightest to heaviest

  • The number of sharp separators is equal to the number of components minus one

This interface is written in language C and it is implemented on Windows NT, IBM RS6000, HP and SUN (SunOS and Solaris) workstations. The way this interface works is through the use of different menus; it is flexible and easy to use. Given the data of the problem, GLOBSEP creates a new GAMS file containing the model equations and optimizes the problem using the solvers MINOS5 for the LP section and CONOPT or MINOS5 for the NLP.

GLOBESP has been developed by Beatriz Bolio under the supervision of Ignacio E.Grossmann .

References for GLOBSEP:

Quesada, I. and I. E. Grossmann, Global Optimization of Bilinear Process Networks with Multicomponent Flows , Computers chem. Engng Vol. 19, No. 12, pp.1219-1242, 1995.

Bolio, Beatriz, Guidelines for GLOBSEP Interface, Carnegie Mellon University, Engineering Design Research Center, Pittsburgh, PA.