Optimal Control of Surfactant containing Multiphase Systems – Challenges and Solution Strategies for a stable Mini-Plant Operation

In this contribution, a model-based approach for the control and stable operation of a mini-plant for homogeneously catalysed reactions in microemulsions is presented. Within these systems, the control of the crucial reaction and phase separation steps is hindered by sensitive shifting operation windows and immeasurable concentrations. Combining the optical observation of the separation state and an underlying phase separation model, a soft-sensor is created to identify these relevant concentrations. Together with plant measurements, a moving horizon state estimation is used to calculate a consistent and validated state of the full plant model, which is then used in a dynamic optimization to calculate optimal trajectories for the mini-plant operation. Hereby, a stable separation is achieved for up to 200 h mini-plant campaigns, alongside an efficient reaction performance with up to 38 % yield and a chemoselectivity of 95 %.DFG, 56091768, TRR 63: Integrierte chemische Prozesse in flüssigen Mehrphasensysteme

Development of a State Estimation Environment for the Optimal Control of a Mini-plant for the Hydroformylation in Microemulsions

A state estimation framework for a surfactant containing multiphase process for the hydroformylation of longchained alkenes is presented. Firstly, available state estimation methods, such as the extended Kalman filter, the unscented Kalman filter and the particle filter are compared regarding their usability in processes with high model and measurement uncertainty. Subsequently, an MHE-based state estimation algorithm is introduced. This includes an approach, which handles the occurring multi-rate measurements by dividing the state estimation into two separate steps. Finally, the implementation is discussed regarding necessary requirements and the state estimation framework is applied within long-term real process operation in a mini-plant.DFG, 56091768, TRR 63: Integrierte chemische Prozesse in flüssigen Mehrphasensysteme