Break the foam with ultrasound

In the technical production of food and beverages as well as fine chemicals, unwanted foam formation often occurs. Typical examples of such processes include the extraction of alcohol from mash during spirits production, milk pasteurization, or biodiesel production. Foam can alter the processes occurring in the equipment so significantly that the apparatus must be shut down. Unwanted foam formation causes high pressure losses and reduced plant throughput. Furthermore, it leads to contamination of the products – the efficiency of material separation decreases. The financial consequences of this phenomenon are particularly significant for small and medium-sized enterprises. Depending on the size of the plant and the industry, losses of up to 100,000 euros per day can be expected.

A multidisciplinary research cluster titled "Physically Based Management of Disruptive Foams in Production Plants: Prevention, Inhibition, and Destruction" addresses how this foam formation can be suppressed. The Department of Food Biotechnology and Process Engineering at TU Berlin, headed by Prof. Dr.-Ing. Cornelia Rauh, and the Department of Dynamics & Operation of Technical Plants at TU Berlin, led by Prof. Dr.-Ing. Jens-Uwe Repke, which conceived the project, are involved. The Federal Ministry for Economic Affairs and Energy (BMWi) is funding the project with nearly 2.8 million euros until 2021. Of this, one million euros are allocated to TU Berlin.

The goal of the project is to develop physically based measures that can be used to prevent, inhibit, and destroy foams. Inhibitory measures refer to actions that, if foam formation cannot be completely prevented, at least reduce it. Ultrasound is a particularly promising tool, used to stimulate and destroy foam bubbles. Additionally, the specific location of foam formation is investigated, as well as the dependence of foam formation on parameters such as temperature and material. Furthermore, the researchers are exploring whether foam formation in real plants can be modeled and simulated on a computer, and whether the results can be transferred to a large-scale industrial setting.

The development of a forecasting tool for the process industry aims to help assess whether there is a risk of unwanted foam formation in the production plant. If necessary, suitable countermeasures will be proposed. This could potentially eliminate the need for chemical defoaming agents, which are currently used to suppress foam. However, these agents also have disadvantages. Besides the costs for purchasing defoamers, they can also reduce material transport within the plant. Moreover, they must be laboriously removed from the product afterward, which is particularly important in food technology.

In addition to TU Berlin, the project involves FAU Erlangen-Nürnberg (coordinating the research cluster), TU Braunschweig, and the University of Hohenheim. It is also supported by more than 40 companies from the chemical, beverage, and food industries, as well as representatives of measurement and control technology.

Further information gladly provided by:

Prof. Dr.-Ing. Cornelia Rauh
TU Berlin
Department of Food Biotechnology and Process Engineering
Tel.: 030/314-71250
Email: cornelia.rauh@tu-berlin.de

Prof. Dr.-Ing. Jens-Uwe Repke
TU Berlin
Department of Dynamics & Operation of Technical Plants
Tel.: 030/314-23893
Email: j.repke@tu-berlin.de