As it launches Dyckerhoff Weiss Blue Star, a white pozzolan cement, Dyckerhoff (Buzzi SpA Group) is reducing CO2 emissions for its white cement.
It is now a question of transferring white cement to a CO2-efficient future. Possible substitutes for the clinker come from the areas of natural and artificial pozzolan. Unfired limestone can also be a useful substitute, depending on the application.
Limestone powders are physically-processed mineral additives that have been used successfully in grey cement production for decades and can also be a useful addition to white cement if the colour is suitable. Natural pozzolana, eg of volcanic origin, and artificial pozzolana, such as calcined clays, can also be interesting feedstocks for the production of white cement.
For some time now, the Dyckerhoff experts have been working on these alternative ingredients in laboratory and technical tests. "In the past few months, the development stage has been completed, successful factory tests have already been carried out in the Dyckerhoff white cement production facility in Wiesbaden, and practical applications of the cements produced in this way have been very promising," claims Dyckerhoff. Dyckerhoff Blue Star is a first for white cement, the company says.
