The use of microreactors in the chemical industry has increased significantly in recent years. Simulations help to better understand the processes in microreactors.
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Chemical production in small reactors is considered effective and safe in process engineering. The use of microreactors also promises faster process development. At Fraunhofer ITWM, we develop methods for simulating and designing such microreactors.
Micro reactors are particularly used in the manufacture of chemical components. The basic principle is simple: two starting materials are brought together in a fine channel. They flow through the channel and react with each other.
Depending on the type of reaction, heat must either be added or removed. At the end of the channel, the desired end product has been created from the starting materials.
But of course, the reality is not quite that simple: to increase productivity, many channels usually run in parallel. Several reactions take place in succession through complicated channel structures. The channels are embossed into plates, and stacking them creates an entire reactor block.
We simulate the microreactor using a model that links the relevant physical effects. Within the channels, we describe heat and mass transfer as well as mixing. The temperature and mass concentrations determine the reaction rate at which the starting materials are converted into end products. The reaction consumes or generates heat, which is exchanged via the plates. We also take into account any coolant circuit that may be present to regulate the reactor temperature in the model.
The simulation allows the state of the reactor to be monitored and controlled. The simulation calculates the state of the system from a few optimally placed measuring probes. It then serves as a virtual probe and provides reliable temperature and concentration data for almost any position. Based on the simulation model, we develop methods for designing the shape of the channel structure. By cleverly choosing the shape of the feed geometries, for example, equal conditions in terms of flow and temperature level can be created between the channels, thus optimizing the productivity and stability of the process.
Fraunhofer Institute for Industrial Mathematics ITWM