TABLE OF CONTENTS In many processing facilities, mass exchangers are used to separate targeted species from a number of rich streams. More than one mass exchange technology and more than one MSA may be considered. In such situations, it is necessary to integrate the decisions and design of the multiple mass exchangers. This requires a holistic approach to consider all separation tasks from all rich streams, simultaneously screen all candidate mass exchange operations and MSAs, and identify the optimum network of mass exchangers. El-Halwagi and Manousiouthakis (1989a) introduced the problem of synthesizing mass exchange network MENs and developed systematic techniques for their optimal design. The problem of synthesizing MENs can be stated as follows: Given a number N R of rich streams (sources) and a number N S of MSAs (lean-streams), it is desired to synthesize a cost-effective network of mass exchangers that can preferentially transfer certain species from the rich streams to the MSAs. Given also are the flowrate of each rich stream, G i, its supply (inlet) composition 
, and its target (outlet) composition 
, where i = 1,2, ..., N R. In addition, the supply and target compositions, 
and 
are given for each MSA, where j = 1,2, ..., N S. The flowrate of each MSA is unknown and is to be determined so as to minimize the network cost. Figure 4-11 is a schematic representation of the MEN...
