The ratio is about 1:1, the Stadtwerke Bonn (SWB) says and for the first time gives concrete figures: For every tonne of waste, about one tonne of CO2 is emitted. The waste incineration plant wants to counteract this high emission of climate-damaging gases and initiated a research project with the Technical University of Aachen three years ago. The first results are now available.

The cooperation with the Technical University's Research Institute for Water and Waste Management lasted three years. The experts designed two laboratory plants for CO2 capture and installed them at the Bonn waste incineration plant as a pilot project. The plants are to be used to find new ways of capturing the carbon dioxide contained in the flue gases and recycling it. According to SWB, it will then be synthesised into methanol through the addition of hydrogen and thus become usable.

Methanol is used in the chemical industry to produce plastics or fuel. The trial phase in the Bonn mini-lab has now been completed. Successful? Yes, it works, the researchers assure us after the first practical tests: CO2 stays in the filter.

"Both plants have produced good results and shown that we can effectively capture CO2 from waste incineration flue gases," says Carl Fritsch of the Research Institute for Water Management and Climate Future at RWTH Aachen University. The implementation of both technologies in the long term would therefore be possible, but a large plant would have to be constructed.

Fritsch is motivating the MVA to act: "Funding policies are very favourable right now." However, it is still a long road to implementation: "We still lack understanding of how much energy is needed. It's not that easy to get green hydrogen," says MVA managing director Manfred Becker. That is why they are now looking for a partner.

"We are the source of CO2, so we have to do something about it," admits Becker. An important contribution to climate protection, however, is waste avoidance, which leads to less waste being incinerated. "I appeal to everyone: produce less waste!" emphasises Becker. For example, one goal could be to reduce carbon dioxide emissions by half. With the new technology, the emission of 125,000 tonnes of CO2 could then be avoided. This could also reduce the number of emission certificates that SWB has to buy. The expenses for this will be passed on to the customers.

One proposal is that other companies can use the test facility for further projects until at least the end of this year. In this way, MVA Bonn would like to develop into a centre of excellence where partners from outside the industry are also given space to "gain important insights for climate protection", they say. (Original text: Sebastian Flick /Translation: Jean Lennox)