Research

Fouling is the unwanted deposition on surfaces in process plants, especially in heat exchangers. These fouling layers reduce the heat capacity of the apparatus, which may result in higher investments and operational costs, shutdown periods, as well as product damage. Different types of fouling occur such as crystallization fouling, biofouling, particulate fouling or reaction fouling.

At present, research activities at the ICTV are related to crystallization, particle and reaction fouling as well as fouling and cleaning (Cleaning-in-Place CIP) in food processing. With test rigs from bench to pilot plant scale the determining material, technical and operational parameters for the fouling respectively cleaning process are investigated and subsequently transferred into models and simulations. Thereby AI tools are also applied. Objective is the prediction of the fouling behavior under process conditions and based on this the identification of suitable measures for the prevention or mitigation of fouling. Cleaning is considered holistically with the preceding fouling process.

Read more about the current research projects here.

The research group “Technologies of heat and mass transfer” systematically analyses individual apparatus and unit operations that are used in the process industries for heat transfer and separation, as well as their integration into overall processes. At apparatus level, modified and novel geometries and apparatus components such as HiTran® elements, packings and micro heat exchangers are analysed experimentally in order to optimise the performance of the apparatus and adapt it to challenging process conditions - such as vacuum operation, foaming, fouling, etc.

Furthermore, complete evaporator units are available in various dimensions, for example natural circulation evaporators (thermosiphon reboilers), thin film and short path evaporators as well as a forced circulation flash evaporator, in order to evaluate the performance of the aforementioned design variants and equipment installations. Another focus is on the modelling of individual mechanisms in the interaction of fluid dynamics and heat transfer as well as their experimental investigation in order to develop surrogate models or semi-empirical modelling approaches.

In the specific case of natural circulation evaporators, the focus is on extending the operating range and increasing heat transfer by modifying the heat-transferring surface, for example by means of surface structuring or the use of pillow-plates. Thin-film evaporators are frequently used for the thermal separation of sensitive material systems; correlations for the design and scale-up of thin-film evaporators are derived taking into account all influencing parameters - material, equipment and operational. In addition, a combination unit consisting of a thin-film and short-path evaporator is available as a platform for process development-related issues.

Several rectification columns on a DN150 and DN50 scale are also available for carrying out separation performance measurements, for example on standard mixtures as well as on non-ideal or aqueous mixtures.

In the context of closing the material cycle of lithium-ion batteries, new process steps to be integrated for the recovery of electrolyte components by means of fractionating batch rectification are being investigated experimentally and simulatively. The methodological challenge here is the separation and re-representation of a predominantly undefined and variable multi-component mixture. In addition to the separation of the solvents within the electrolyte, the recovery of lithium-containing conductive salts and the polymer-based binder using extractive processes are also the subject of current research activities.

Read more about the current research projects here.