• A novel machine learning (ML)–based framework for integrating scheduling and control in chemical process operations is proposed. • Open- and closed-loop process dynamics are approximated by ML models and then embedded into the scheduling formulation, leading to a MINLP problem. • The framework extends the current state-of-the-art methods for integration in process systems. • It results in a tractable MINLP problem while preserving high accuracy in approximating the process dynamics. • The scheduler’s adaptiveness is enhanced to handle both scheduling uncertainties and process level disturbances. The integration of scheduling and control in chemical process management offers significant efficiencies and economic benefits. However, practical implementation remains challenging due to the complex mathematical formulation. Therefore, pursuing formulations that are both accurate and computationally tractable has consistently remained a central, rapidly evolving research topic. This work presents a machine learning (ML)-based framework for integrated scheduling and control, where deep neural networks (DNNs) are leveraged to address the complexity arising from both the process models and the control layer. The DNNs are trained offline to approximate two key components: (i) the nonlinear open-loop process dynamics (i.e., process model) and (ii) the closed-loop scheduling-adaptive control policy, which establishes a mapping from higher-level scheduling decisions to lower-level optimal control actions. The two DNNs are then embedded into a classical scheduling formulation with an economic objective, resulting in an integrated mixed-integer nonlinear program (MINLP), which accounts for both process dynamics and control logic, while eliminating the need for repeated online evaluation of the complex process model or solving the nonlinear model predictive control (NMPC) problem. The integrated MINLP is solved using a Genetic Algorithm, which handles both discrete and continuous decisions. Application to a multi-product continuous stirred-tank reactor (CSTR) demonstrates the potential of the proposed framework to achieve tractable scheduling–control integration, generating optimal schedules that satisfy varying demand targets and rush-order scenarios. Compared with a baseline case, where product transition times are represented only by statistical estimates, the proposed approach yields an economic gain of approximately 50% in the scheduling objective.
Qassime et al. (Sun,) studied this question.