(47e) New Optimization-Based Approach to Process Synthesis - towards the Full Integration of Process Design, Operation and Control

Conceptual process design still follows a traditional procedure which consists of three sequential stages, as depicted in Figure 1. In the first stage, the operation mode is selected according to the particular process and manufacturing demands. The decision is strictly based on heuristic rules, for instance batch operation is preferable for small capacities and multi-products while continuous operation is recommended for bulk production of a single product. In the second stage, the process is designed according to the process' physical and chemical characteristics, desirable production rate and quality and related economical issues. Although in this step equipment dimensions are commonly calculated using mathematical models, this phase also heavily relies on heuristics. In most cases predefined process units for a specific application are used and a selection of units is completed according to this practical method. In the third phase, a control system is designed for the purpose of maintaining the specified product quality and quantity, as well as process safety. This procedure is well established in practice; it offers ready-made mathematical models and technical solutions. However, it does not allow the interaction of design, operation and control and therefore it is generally suboptimal from both economical and environmental perspectives.