Laboratory of Reaction and Fluid Process Engineering

Smart batch processes in the energy system of the future

Accounting for 11% of electricity demand, the process industry is one of the main consumers of electrical energy in Germany. The switch to a renewable electricity supply is therefore of crucial importance for the success of the energy transition. While electricity demand was previously covered according to demand, a variable regenerative power supply requires processes to adapt flexibly to the electricity supply. This requires fundamentally new methods and processes to be developed and tested in real-life applications.

The project places a particular focus on batch processes and DC-based supply grids. DC-based supply grids are particularly advantageous for linking electricity-based production processes with renewable generators and storage facilities. Batch processes are widespread in both SMEs and large companies and therefore make a significant contribution to electricity demand. In contrast to continuous processes, batch processes are still largely unexplored in terms of flexibilization. They are characterized by the fact that different units (stirrers, pumps, electric heaters, etc.) are started up and shut down in the course of a cycle in order to carry out different process steps one after the other.

Batch-based production processes and DC-based supply networks are set up and investigated on a laboratory scale in demonstrators. The project will be supported by an industrial advisory board in order to incorporate the needs of practical applications at an early stage.

The LRF is working on the following parts of the project:

  • ChemPro demonstrator: This demonstrator will be used to couple water electrolysis with hydrogenation. The electrolytically produced hydrogen will not be used as an energy storage medium, but will be used directly in the chemical reaction. The focus of the demonstrator is on the development and testing of control strategies in order to be able to operate the hydrogenation even with limited power availability of the electrolysis without losses in conversion and yield. The hydrogenation of cinnamaldehyde to cinnamyl alcohol serves as a model reaction. A kinetic study of this reaction is first carried out to design and control the process control. Based on the kinetic data obtained, a sensitivity analysis is carried out to identify the decisive influencing variables on the reaction. The results of this analysis ultimately form the basis for the development of suitable control strategies.
  • Demonstrator AerBio: This demonstrator deals with the industrial production of citric acid as an example process. The process is characterized by a large number of process steps that are widely used in process engineering and is therefore suitable as a model process for the broad-based investigation of the flexibilization potential of various unit operations: the fermentation for the production of citric acid is an aerobic bioprocess, the downstreaming includes precipitation, filtration, chromatography and drying processes. This study analyzes the economic potential of flexible batch processes. In addition, process engineering issues arising from flexibilization will be addressed and solved.

 

The project is interdisciplinary in nature and involves cooperation with a large number of chairs at RPTU:

  • Bioprocess engineering
  • Mechanical process engineering
  • Electrical engineering
  • chemistry
  • Measurement and control engineering
  • production planning

The focus of research at the LRF is on

  • Development of flexibilization strategies with regard to electricity prices and the availability of renewable energies on the electricity market
  • Simulations to investigate flexible operating modes and/or capacity of batch processes in Aspen and Julia.
  • Experiments to investigate the influence of flexible operation on productivity, selectivity and product quality of various processes
  • Derivation of models from experiments for simulations of industrial-scale processes