Integrated Production Planning and Model Predictive Control of a Fluidized Bed Catalytic Cracking-Fractionator Unit

Abstract

The present study proposes a new production planning framework that considers the effect of closed-loop control and process disturbances/disruptions. The production planning layer is augmented to include process control degrees of freedom, process operating constraints, operating uncertain parameters (related to closed-loop feedback), and disturbance information. This results in a stochastic production planning problem, whose solution successfully reduces the economic gap between production planning predictions and realized production. The proposed approach is applied to a large-scale model of a refinery section comprising a fluid catalytic cracker (FCC) and a fractionator. Extensive simulations involving different disturbances, operating modes, models, and production planning formulations are performed. The results demonstrate the benefits of the proposed framework in terms of economic performance, computational tractability, and ease of application. Finally, the impact of the economic model and plant-model mismatches between production planning and model predictive control (MPC), which arise in practice, is investigated.