Research projects

The replacement of primary fuels by alternative fuels is of great economic and ecological importance for the cement industry and is to be increased in the future. The fuel ashes are used as raw material in the cement clinker and influence its properties as well as the coating formation on the refractory lining in the kiln. Exact knowledge of these effects is indispensable for the further increase of the alternative fuel rate and the simultaneous optimisation of the kiln operation as well as for the maintenance of the clinker quality and the service life of the refractory lining.

The aim of the research project is to investigate the suitability of previously largely unused mineral secondary raw materials from the stone and earth industry as a resource-conserving and climate-friendly main cement constituent. The use of cal-cined clays from secondary raw materials instead of conventional main cement constituents or high-quality primary clays can make an important contribution to the production of climate-friendly and resource-efficient cements.

The aim of the research project was to develop a procedure for analysing trace elements on cements using X-ray fluorescence analysis. In addition, precision data and application limits were to be determined, which are essential in order to be able to classify the results.

The research project analysed whether sulphate-rich process dusts can be used to optimise the sulphate content of cements, thereby saving anhydrite/gypsum and, in particular, improving the early strength of cements with several main constituents. Furthermore, it was to be determined whether isothermal heat flow calorimetry can be used as a fast and cost-effective investigation method for this purpose.

The acceptance of resource-efficient cements with significantly reduced specific CO₂ emissions is still too low in construction practice. The main reason for this is that early strength is not high enough for economical production processes and also competitive construction with concrete. Accelerating admixtures can improve the early strength of concrete. The research project investigates interactions between concrete admixtures that accelerate the strength development and cements with several main constituents.

The acceptance of resource-efficient cements with significantly reduced specific CO₂ emissions is still too low in construction practice. The main reason is that the early strength is not high enough for economical production processes and competitive construction with concrete. The research project is investigating the extent to which more intensive mixing and further cement constituents besides clinker increase the mixing energy input and can increase the early cement hydration and thus the strength development.

The aim of the research project is the detailed investigation of the performance, durability and hydration behaviour of ternary cements with blastfurnace slag and calcined clay as main constituents (KSQ cements).

The research project has two objectives. The first is to investigate whether certain chemical / mineralogical properties can make clinker more robust against pre-hydration effects. Secondly, it will be investigated which measures can be taken to counteract possible negative effects, in particular by adjusting the sulphate carrier composition.