Pozzolana from calcination of calcareous and doped clays and investigations on their hydration behaviour in cement

Aim of the project is the investigation of the reactivity of thermal activated lime-containing and doped clays in continuation of the projects IGF 16566 N and IGF 17930 N.

In the project, the thermal activation of ceramically low grade clays containing lime and quartz is investigated. Both natural clays with high amounts of calcite and also clays with additions of lime, gypsum or bypass dust are calcined. Special attention is paid to the investigation of the resulting reactive mixed phases and their hydration reactions. Cement technological investigations will prove the efficiency of such activated pozzolanas in cement.

An important criterion for the use of calcined clays in cement is not only their technological performance but also the achievable CO2 saving potential. Therefore, a well-founded calculation of the realistic CO2 saving potential is carried out on the basis of different calcination techniques and of the clinker substitution rate.

Supported by

The IGF project 19744 N of VDZ gGmbH was supported by the AiF within the framework of Industrial Collective Research (IGF) of the Federal Ministry of Economic Affairs and Energy on the basis of a decision of the German Bundestag.