Page 98 - Design of Simple and Robust Process Plants

4.1 Process Synthesis 83
Both methods are applicable, and are sometimes combined where the MINLP sol-
ving is initially used to reduce the number of alternatives. With a reduced set of
alternatives, NLP optimization is applied and the alternatives reduced by evaluation.
A layered approach is selected for optimization, that fits in the process synthesis
methodology (Figure 4.3). The optimization layers are projected over the process
synthesis methodology as is shown in Figure 4.4. Such a layered approach has the

Fig. 4.3. A layered optimization approach.

Fig. 4.4. Process synthesis: methodology including layered optimization.