VATIS UPDATE Article

A research project under the auspices of LEILAC (Low Emissions Intensity Lime and Cement) consortium, has announced a promising project regarding sustainable cement production: over the next five years, a cutting-edge testing facility is to be set up to rigorously assess new technology for the capture of carbon dioxide (CO2). The research consortium includes HeidelbergCement, Germany, technology company Calix, Australia,and other cement and lime producers, as well as research and development institutions.

Calix entered the market two years ago with a reactor used to directly separate CO2 from magnesium minerals. Now, the same technology is to be used to capture the CO2 produced by the cement manufacturing process, two-thirds of which come as emissions from the burning (calcination) of limestone. The temperature necessary to drive out CO2 from limestone, however, is significantly higher than needed for magnesium. Therefore, the Calix technology must be further engineered and intensively tested in the field.

The opportunities this technology will open up are tremendous: Integrated into the calcination process, the Calix reactor is capable of capturing almost pure CO2 released from the limestone. The system is unique in that the heat of the exhaust gases is transferred to the limestone via a special steel vessel. In this way, the reactor is heated indirectly, with the gas never coming into contact with the limestone. The CO2 released from the limestone can therefore be separated in an almost pure form. This technology offers an added benefit, as it can capture these emissions without significant energy or capital expenditures.