(381w) Design of Process Control Schemes and Experimental Investigation for a Transesterification in a Reactive Dividing Wall Column

Process integration is an important method to increase the process efficiency in the chemical industry. A highly integrated process is represented by the reactive dividing wall column (RDWC), which combines a chemical reaction and several separation steps in one column shell. Theoretical studies state that the energy demand of RDWCs can be reduced up to 15 % and investment costs up to 30 % in comparison to conventional separation sequences.[1] On the other hand the high degree of integration leads to very complex process behaviour, hence the chemical industry is reluctant to build and operate RDWCs. In order to assure constant product purities and a stable continuous operation, reliable process control strategies are required. To date various papers assess the design and steady state operation of the RDWC in simulation studies. However, there are only few papers about dynamic operation and process control and even less papers that show experimental results for RDWC process control.

Hence, our research aims to provide theoretical and experimental insights into the dynamic process behaviour of RDWCs. Therefore, we develop a systematic approach for the design of suitable RDWC process control schemes. Our research combines simulation studies with our validated dynamic RDWC model, developed at the Institute of Process and Plant Engineering, University of Technology Hamburg, with experimental tests of the process control schemes in a 12 m pilot plant RDWC. The employed reaction system, the transesterification of hexyl acetate with butanol, is well suited as a reference system for esterification, transesterification and hydrolases reaction systems.

The poster presentation will show the systematic development of process control schemes for the RDWC as well as the experimental investigation of these control schemes. First, the research concept, the reaction system and the pilot plant RDWC are shown. Our systematic approach for the development of control schemes suitable for an efficient and stable RDWC operation is presented. An exemplary control scheme is developed for the reference system and experimental test results are employed to assess its performance.

[1] Schröder, M.; Fieg, G. (2016): Influence of Reaction System Properties on the Energy Saving Potential of the Reactive Dividing-Wall Column: Separation Properties. In Chem. Eng. Technol. 39 (12), pp. 2265–2272. DOI: 10.1002/ceat.201600134.