The project aims to develop and investigate a new process for CO₂ capture in which raw meal calcination does not take place in the cyclone preheater with calciner but in separately operated, energy-efficient oxyfuel shaft kilns. This is preceded by raw meal briquetting and followed by a slightly modified conventional rotary kiln for burning the clinker. Since the entry of false air is prevented by the overpressure in the shaft kiln, a very high CO₂ concentration in the separated gas is possible, which makes the subsequent gas purification significantly more cost-effective than conventional processes. Another advantage is that the shaft kilns do not have to be operated at the same location as the rotary kiln plant. This could even lead to erecting them near existing CO₂ pipelines and sinks. This avoids time delays and costs for expanding the CO₂ transport infrastructure.
The project aims to develop the essential scientific and technical principles for the process concept and to demonstrate its potential and limitations. In the first phase of the project, laboratory tests will be carried out on the calcination of raw meal briquettes in a chamber kiln. In the second phase, different process combinations of shaft calciners and rotary kiln plants will be investigated using process simulation in order to determine the most suitable process variant from a technical and economic point of view.
