Page 97 - Analysis, Synthesis and Design of Chemical Processes, Third Edition

that chapter, considerable emphasis is placed on the sequencing of distillation columns, and some of the
problems associated with azeotropic systems are covered.

2.6 Step 5—Heat-Exchanger Network or Process Energy Recovery System

The main objective of process energy recovery is to optimize the energy that a process exchanges with the
utilities. At the expense of capital investment, the utility usage can be decreased by exchanging energy
between process streams. The amount of energy integration is a function of the relative costs of the
utilities. In addition, the process becomes more complex and more difficult to control. This loss in
flexibility must be weighed against the savings in operating costs. These and other issues are covered in
more detail in Chapter 15.

2.7 Information Required and Sources

In formulating a process flow diagram, one of the most important tasks is the collection and synthesis of
data. These data are available in a wide variety of publications. As a guide, a summary of useful

resources is presented in Table 2.3. The data in this table are partitioned into information pertaining to
new and existing processes and data on new and existing chemical pathways.

Table 2.3 Summary of Resources for Obtaining Information on Chemical Processes