Decision-based approach to plantwide control structure synthesis

The concept of plantwide control structure synthesis is not new to the chemical process industry. The approaches used can be classified into two main categories: a process engineering approach and a mathematically oriented approach. Within each category, there is no consensus as to one approach, which is not surprising given the size, complexity, and objectives of any plant. This work describes a modular decomposition of plant flowsheets that is assessed according to a decision-based approach, the analytical hierarchical process, that consistently evaluates the merits of the decomposition among alternatives and between neighboring modules to arrive at a prioritization of objectives for each module and for the integrated plant. An example system is discussed to demonstrate the approach.