Closed-loop control of a polymerisation plant using production performance indicators (PIs)

The synthesis of plant-wide control structures is recognised as one of the most important production-management design problems in the process industries. This article proposes a closed-loop control structure utilising production performance indicators (pPIs) as a possible solution to simplify this problem. pPIs represent the translation of operating objectives, such as the minimisation of production costs, to a set of measurable variables that can then be used in a feedback control. The idea of closed-loop control at the production-management level using pPIs as referenced controlled variables was implemented on the procedural model of a production process for a polymerisation plant, and two types of controllers were tested: an experimental controller based on look-up tables, and an advanced model predictive controller (MPC). Preliminary results show the usefulness of the proposed methodology.