Most concretes used at present are based on Portland cement which is a well-known and very good cementitious binder. Unfortunately, the production technology requires application of high temperatures reaching over 1400 oC which results in emission of 900 kg of CO2 per each produced ton of cement. The present yearly worldwide production of Portland cement is over 2 billion tones, which corresponds to a CO2 emission of 1.8 billion tons annually!
Reduction of CO2 emission related to Portland cement can be achieved by optimization of the production process or decreased amount of the used Portland cement. The ClayCem project aims to develop a new sustainable and possibly recyclable cementitious material suitable for production of structural concrete. The ultimate CO2 footprint is hoped to be lowered by at least 50% in comparison with Portland cement. ClayCem will be based on low quality natural clay minerals occurring in Sweden. The raw material will be activated by novel process. The project will be led by Professor Andrzej Cwirzen (Structural Engineering) in close cooperation with Professor Jan Laue (Soil Mechanics).
"Clay is common in Scandinavia. Civil engineers often face either solid rock which is a perfect subgrade for foundation work or clay which in most cases causes problems and needs to be replaced or strengthened. The aim of our project is to turn that low quality clay into a good cementitious material which could replace Portland cement", says Professor Cwirzen.
The ClayCem project will start in 2017 and will end after 3 years with organization of an International symposium on alternative ecological cementitious binders for concrete.