A decentralized control strategy for improved batch tablet coating process operation

• Published in: Computers & chemical engineering Vol. 187; p. 108741
• Main Authors: Rodrigues, Cecilia Pereira, Poulin, Éric, Duchesne, Carl, Lapointe-Garant, Pierre-Philippe
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.08.2024
• Subjects: Batch time reduction; Energy reduction; Pharmaceuticals; Process control; Tablet film coating; PI; Energy reduction; Tablet film coating; Batch time reduction; Process control; Pharmaceuticals
• ISSN: 0098-1354; 1873-4375
• DOI: 10.1016/j.compchemeng.2024.108741

•Introduction of a control strategy for batch tablet film-coating processes.•Effective use of available process data for online control of critical variables.•Use of a dynamic process simulator to validate a decentralized PI controller.•Potential reduction in total batch processing time and energy consumption. This paper proposes a control strategy for batch tablet film-coating processes using readily available process instrumentation. Outlet air conditions (temperature and relative humidity), which impact coating quality, are controlled by the manipulation of inlet air temperature and coating spray rate. Controller design, tuning and validation rely on the use of a dynamic process simulator, calibrated using data collected from a pilot plant coating unit. The final 2 × 2 decentralized PI controller demonstrated good performance for both setpoint tracking and disturbance rejection in simulation. Additionally, controlled variable setpoints were determined to maximize plant profits considering batch duration and energy consumption as optimization criteria. For the case study considered, the total batch processing time can potentially be reduced by 40 % while simultaneously reducing energy usage by 30 %, in comparison with the more conservative fixed recipe approach typically adopted in production.