We want to deliver high-grade products of consistent quality that our customers can rely on. To achieve this, we have set ourselves high standards, but we also must comply with legal requirements. In addition to many other quality assurance measures, a complete set of all raw materials used in the production of autoclaved aerated concrete and Multipor is therefore tested and evaluated every year at Xella Technologie- und Forschungsgesellschaft. Torsten Schoch, Managing Director of Xella T&F, explains more about this here in the video:



The conditions for optimal usability of our raw materials are very individual. For example, the building materials autoclaved aerated concrete and calcium silicate, which make up the majority of Xella's product portfolio, place special demands on the sand used in their production. Sand for autoclaved aerated concrete should contain a high proportion of quartz, at least 80 percent, in order to be able to ensure lower gross densities in the end product. This low bulk density results in better thermal insulation and a lower weight of the blocks and thus easier handling.

Evaluate new raw materials
In view of climate change, lime and cement production is to become more environmentally friendly. For this reason, work is being done on optimized firing processes that release fewer CO2 emissions through lower temperatures or shorter firing times. But so that the raw materials lime and cement produced in this way can be used for the manufacture of Xella products, certain parameters must be checked: The cement requires a precise analysis of the reaction and setting behavior.

A low-emission production method can also lead to a changed reaction sensitivity of the lime. For the production of calcium silicate units, the faster reacting limes, which are already produced at lower firing temperatures, are optimal, whereas for the production of autoclaved aerated concrete, rather slow reacting limes are advantageous. "A challenge for the future is above all to adapt the autoclaved aerated concrete recipes to the changed properties of the lime produced in this way", explains Torsten Schoch.

More about the work at Xella T&F.