A general modelling toolbox has been developed that enables efficient development of rigorous and hybrid models for crystallisation (deliverables 2.1 through 2.6).
The toolbox covers a comprehensive range of crystallisation processes with respect to operation mode (batch, semi-batch and continuous), super-saturation generation technique (cooling, flash-cooling and evaporation), crystalliser types (stirred vessel, draft-tube, draft-tube-baffle, forced circulation, column, etc.) and process configuration (single or multiple stage, with or without classification devices). As such, the toolbox enabled rapid development of dedicated crystallisation process and product models for all end-users using a variety of chemical components (including additives and impurities), crystallisation mechanisms and process scales.
Models developed using this toolbox can be readily applied for simulation, parameter estimation and optimisation purposes. With respect to parameter estimation, a protocol aimed at the determination of the kinetics parameters of crystallisation on the lab-scale and thus validating the corresponding, overall model within a short time frame was developed. The validated model can then be used in combination with formal, mathematically based optimisation techniques to optimise design and/or operation of a crystallisation process.
The toolbox has undergone elaborate tests using crystallisation processes of all the end-users involved in the SINC-PRO project at lab, pilot and production scale.
Results obtained with this simulation toolbox have been published and presented on several occasions. The key publications/presentations are:
"Development and validation of models for optimisation and control of batch and continuous crystallisation processes" (Paper and oral presentation), ISICIPT conference, Nov 2004, Chiba, Japan.
"AML:SC - The Advanced Model Library for Solution Crystallisation" (Oral presentation and demonstration), PSE User Meeting, March 2005, London, UK.
"Efficient development of rigorous crystalliser models - a hierarchical model framework" (Oral presentation and demonstration), SINC-PRO public workshop, April 2005, Delft, The Netherlands.
"Model validation, model-based process optimisation and scale-up - crystallisation case studies from the food industries" (Paper accepted for oral presentation), ISIC conference, Sep 2005, Dresden, Germany.
The model library at the heart of this modelling toolbox will be exploited by Process Systems Enterprise Ltd (PSE) as the Advanced Model Library for Solution Crystallisation (AML:SC). The user interface and modelling engine required for use of this toolbox are part of an existing product from PSE: gPROMS, which has been a commercial product since 1997. gPROMS dates back to 1988 when its development was started at Imperial College of Science, Technology and Medicine.