Plantwide Optimizing Control for an Acrylic Acid Production Process: A combined Stochastic Optimization and Green Chemistry approach

Abstract

ABSTRACT: Traditional decentralized control strategies not consider that disturbances or uncertainties can affect the optimal operation point of processes, reducing economic profitability, increasing environmental impact of them, and operating in infeasible zones where security constraints might be violated. To combat these problematic issues, this work proposes alternatives that assures economic profitability, and environmental care from a plantwide and optimization perspectives. Dynamic optimization is a good strategy for controlling a complete plant. It allows to improve economic profitability reducing environmental impact of processes. In this thesis, we present a Stochastic Plantwide Optimizing Control (SPWOC) approach which handle three sources of uncertainty (internal, external, and process), obtaining solutions that improve economic performance of the process, with excellent performance of the control system, fulfilment of safety constraints for all the analysed scenarios, and reduction of environment impact of the process. A comparison of SPWOC against deterministic Plantwide Optimizing Control (PWOC) and decentralized structures is carried out. Results show the effectiveness of the proposed SPWOC structure for handling different types of uncertainties. Inclusion of green chemistry metrics into the nine steps of the SPWOC formulation showed to be a good strategy to improve environmental aspects of the process.