A Framework for Grade Changes: An Optimization and Sequential Control Approach

In modern chemical process industry, process state transitions, or grade changes, are common operations. Frequent production changes increase the focus on efficient operator support for such procedures. The aims of a grade change may be complex, and sometimes conflicting.Fast transitions are desirable in order to minimize production loss. There may also be safety aspects that must be considered, in order to achieve acceptable risks of failure. Operator acceptance is a key issue for a decision support systems, and is the topic of this paper.We address the problem by combining dynamic optimization techniques and a tool for sequential control; JGrafchart.