For four years now, the Technische Universitat Darmstadt in Germany has been studying an innovative carbon-capturing system, the carbonate-looping method, which aside from being cost-effective, energy-efficient, and having a 90% capturing capacity, is also feasible to be retrofitted in an existing power plant.
The pilot scale carbon-capture plant involves the utilization of naturally occurring limestone (CaCO3), which upon calcination produces quicklime (CaO), which in turn reacts with entering CO2 gas, producing limestone, which is then returned to the calcination process.
After investigating 1,000 operating hours of the pilot plant, it was finally proven that the method provides 90% absorption of CO2 emissions of power plants while the costs and energy inputs are kept low, enabling power plants to be almost CO2-free.
A new project is currently conducted that employs the same carbonate-looping method in a much larger scale with scaling-up factor of 20. The project aims to plan the installation of the method in an existing German power plant.