(167d) System Dynamic, Disturbance Simulation, and Product Quality Implication

The continuous manufacturing platforms include multiple unit operations with seamless connections, and continuous flow of material that goes through different transformations. The system is intrinsically dynamic, which is aimed to be kept under the state of control. The System Dynamic evaluation and knowledge development is required to understand how to keep the system under the state of control, what would be the impact of disturbances on downstream steps and product quality, and develop control strategies. There are many potential disturbances that could deviate the process, such as flow or temperature fluctuations. Also, the residence time distribution (RTD) for single unit operation, cluster, and end-to-end will be required to track the deviation, dispersion, time-to-product, and magnitude-to-product. A combination of these tools and developed knowledge will be essential for maintaining the process under the state of control, developing a control strategy, designing robust control systems, sizing surge tanks, locating deviation points, .... and ensuring consistent product quality.
In this presentation, an industrial scale continuous manufacturing platform of a chemical compound with 2 PFRs, 1 CSTR, and 1 surge tank will be used to demonstrate system dynamics, sensitivity analysis, RTD, funnel plots, and control strategies for different disturbance scenarios. The complex chemistry steps include multiple reactions (and side reactions, which generate impurities), that are sensitive to the flow ratio of reagents and the temperature of reactors. Modeling and simulation tools that were utilized for developing the RTD, TTD, dispersion, process design and optimization, and process control recipe development will be discussed.