About 50 million organic compounds are in circulation worldwide, of which about 5000 are classified as potentially environmentally relevant. In Germany, a densely populated country with many industrial agglomerations, wastewater and water bodies are often exceptionally highly polluted with so-called micropollutants such as pharmaceutical residues. Some of these micropollutants are difficult to break down and have a potentially toxic effect despite their very low concentration in water - usually less than one part pollutant per billion particles of water. To remove the micropollutants, sewage treatment plants in many cases use materials that can bind them. Active charcoal is one such material that binds pollutants to the surface. The water cleaned in this way leaves the sewage treatment plant; the used active charcoal is either disposed of or regenerated and reused in central treatment plants. A disadvantage is that the majority of active charcoal is extracted from hard coal - a non-renewable raw material.
The ZeroTrace consortium's solution covers the entire value added chain, starting with the development of composite active charcoal from a base material and an electrically conductive component. The modified active charcoal is assembled and tested in simple laboratory tests to determine its applicability for eliminating specific indicator micropollutants. A new regeneration process based on EFSA, which has so far only been used in gas adsorption, will be implemented and investigated on a laboratory scale for subsequent piloting. The adsorption capacity of the prioritized active charcoals will be tested at an extended laboratory scale before pilot phases with muncipal and industrial wastewater. The new activated carbon process will be evaluated taking into account socio-economic and environmental innovation drivers and barriers to ensure targeted and sustainable development.
Fraunhofer Institute for Environmental, Safety and Energy Technology UMSICHT