A model-based approach for controlling particle size distribution in combined cooling-antisolvent crystallization processes. (23rd November 2018)

• Record Type: Journal Article
• Authors: Ghadipasha, N.; Romagnoli, J.A.; Tronci, S.; Baratti, R.
• Is Part Of: Chemical engineering science. Volume 190(2018)
• Page Start: 260
• Page End: 272
• Publication Date: 2018-11-23
• Subjects: Crystallization -- Image analysis -- Fokker-Planck Equation -- Particle Size Distribution -- Model-based Control; Chemical engineering -- Periodicals; Génie chimique -- Périodiques; Chemical engineering; Periodicals; Electronic journals; 660
• DOI: 10.1016/j.ces.2018.06.032
• Languages: English
• ISSNs: 0009-2509

Abstract

Highlights: Controlling crystal size distribution (CSD) is important for the end-product properties of particles. Image processing is a promising method for in-situ measurement of CSD. Fokker-Planck equation is an alternative to Population Balance Model for describing CSD. Abstract: This article focuses on the design and implementation of model-based control strategies for real time control of crystal size distribution (CSD) in semi batch crystallization processes. The objective of the feedback controller is to reach a desired particle mean size while the standard deviation is controlled in a feedforward fashion. Alternative model-based control strategies are formulated and implemented for a target mean size. An image processing technique based on wavelet-fractal and energy signature analysis is employed to determine online CSD status for the controller's corrective actions. To validate the proposed model-based control strategies, unseeded crystallization of sodium chloride in water using ethanol as antisolvent is performed in an experimental bench-scale semi-batch crystallizer.