The Sheffield team has been working with US-based start-up CO2Rail to design direct air capture (DAC) equipment that can be placed within special rail cars on already running trains to absorb carbon from the atmosphere, helping to mitigate the impact of climate change.
The DAC rail cars work by using large intakes of air that extend up into the slipstream of the moving train to move ambient air into the large cylindrical CO2 collection chamber and eliminate the need for energy-intensive fan systems that are necessary with stationary DAC operations.
The air then moves through a chemical process that separates the CO2, allowing the rest of it to travel out of the back or underside of the car and return to the atmosphere.
After a sufficient amount has been captured, the chamber is closed and the harvested CO2 is collected, concentrated, and stored in a liquid reservoir until it can be emptied from the train at a crew change or fuelling stop into normal CO2...