Dr. Sara Marchini receives two research awards for her outstanding doctorate

Dr. Sara Marchini, research associate at the Chair of Chemical Process Engineering, was recognized with the Manfred Hirschvogel Prize for the best dissertation in the field of mechanical engineering. The award ceremony took place during the Day of the Faculty of Mechanical Science and Engineering in Dresden. It is the second award that the chemical engineer has received for her outstanding doctoral achievement. She was already honored with the Gisela and Erwin Sick University Prize for Measurement Technology in May of this year. Both prizes are endowed with 5,000 euros each.

In her doctoral thesis, Sara Marchini focused on optimizing gas-liquid contactors, which are widely used in the chemical and biochemical industries. These process engineering devices facilitate chemical reactions between gas and liquid as well as heat and mass transfer. A major aspect of her work is recording hydrodynamic parameters such as the axial dispersion coefficient - a measure of gas mixing within these reactors. Until now, it has hardly been possible to determine this parameter using conventional tracer-based methods. Marchini was the first to develop a systematic, non-invasive and precise measurement approach, called gas flow modulation.

Instead of on the use of chemical tracer substances, this method is based on a light sinusoidal change in the gas flow rate entering the column. This creates a periodic variation in the gas fraction within the bubble column, known as a gas hold-up wave. As the wave extends upwards, it is dampened and shifted in phase by gas mixing. These effects can be recorded at two measuring points along the column. Based on the collected data, the flow conditions in the bubble column can then be precisely calculated using a mathematical model.

From Lab to Industry: Making Bubble Columns More Efficient

This method has the potential to make bubble column reactors more efficient, sustainable and fit for the future. It has already attracted the interest of numerous international partners and led to joint publications and collaborations. Marchini and her team at TU Dresden, in collaboration with Helmholtz-Zentrum Dresden-Rossendorf (HZDR), are currently refining the evaluation software and seeking additional industry partners to transfer the patented technology from the lab to real-world applications.

"I’m very happy that the method I developed in my doctoral thesis, and into which I invested so much time and effort, is now receiving such recognition. The two awards will help me realize my goal of continuing my career in science," says Sara Marchini. “I would like to thank everyone who helped me along the way - my supervisors at HZDR and TU Dresden, and of course my family and friends who have always supported me.”

Sara Marchini began her scientific career in her home country, Italy, studying Chemical Engineering at the University of Pisa. In 2019, she came to Dresden through the EU’s “Erasmus+” program to write her master's thesis in the Department of Experimental Thermal Fluid Dynamics at HZDR. She then pursued her PhD at the Chair of Imaging Techniques in Energy and Process Engineering at TU Dresden. The necessary experiments were conducted at HZDR’s Institute of Fluid Dynamics. Since 2023, Sara Marchini has been a research associate in chemical process engineering at TU Dresden. Her main research interests are chemical energy storage and reactive multiphase flows.

Manfred Hirschvogel Prize

The Manfred Hirschvogel Prize has been awarded annually since 2013 at all TU9 universities - the alliance of Germany's nine leading technical universities - for the best doctoral thesis in mechanical engineering from the previous year. Eligible dissertations must demonstrate innovative and pioneering significance for scientific and technological advancement in mechanical engineering. The award is presented by the Frank Hirschvogel Foundation, which is committed to promoting education, science and research in Germany.

Gisela and Erwin Sick University Prize for Measurement Technology

Since 2017, TU Dresden has awarded the University Prize of the Gisela and Erwin Sick Foundation for outstanding dissertations in the field of measurement technology. The jury places special emphasis on scientific progress and the relevance of research results to practical measurement applications. These may relate to process, factory, or logistics automation, biomedical applications, or environmental protection.

Contact:
Dr. Sara Marchini
Chair of Chemical Process Engineering
Institute of Process Engineering and Environmental Technology
Tel.: 0351 463-32046
Email: