What drives me - Nele Siebert

Our wastewater contains residues of pharmaceuticals and common household chemicals, among other things, which end up in rivers and bodies of water. Some wastewater treatment plants already use activated carbon to remove such trace substances from wastewater. However, conventional activated carbon is produced from lignite or hard coal, has very high_CO2 equivalents and is therefore harmful to the climate.

In the CirCles research training group, we are researching in several steps how activated carbon can be produced from urban biowaste. This is available locally and can replace fossil primary raw materials, thereby avoiding_CO2 emissions. The aim of the project is therefore to create a carbon cycle at municipal level, reduce greenhouse gas emissions and recycle waste at the same time.

My research topic is relatively at the end of the multi-stage process. I want to find out how conventional activated carbon can be replaced by biogenic activated carbon. Is this substitution technically possible? What are the consequences? Is biogenic activated carbon even suitable for use in wastewater treatment plants? To answer these questions, I am examining various activated carbon samples and analyzing how well they absorb different trace substances. The samples are produced by an agricultural scientist who is also involved in CirCles. So far I have been working with powdered activated carbon, but later I will also be investigating granulated activated carbon. Both forms are used in sewage treatment plants. I am very pleased to be doing my doctorate in the Department of Urban Water Management under the supervision of Prof. Dr. Tobias Morck. I previously studied environmental engineering in Kassel and the project ties in perfectly with my main areas of study and my master's thesis on conventional activated carbon. And it's a topical issue: so far there is no legal regulation in Germany for the removal of trace substances from municipal wastewater, because they only became detectable on a large scale thanks to improved measurement technology. However, it is clear that we need to use our resources more sustainably - and we are developing methods to achieve this.

This article appeared in the university magazine publik 2023/2. protocol: Lisa-Maxine Klein