Optimierung des Wasser-zu-Zement-Verhältnisses von ungeformten feuerfesten Erzeugnissen für besseres Verhalten beim Einbau, Trocknen und im Einsatz

The need of the investigations is given by the importance to guarantee a reliable and save service of refractory castables wherever they are used in high temperature applications. Uncontrolled downtimes of thermal facilities may not only cause high economic damage because of re-installation and production downtimes but also have a high risk to cause occupational injuries. An improper treatment of the installed refractory castables can cause explosions during heat up or may not provide the refractoriness and corrosion resistance during the ser-vice time. This may cause in worst case furnace breakthroughs that are inacceptable from the viewpoint of operational safety and process stability. The need for optimized refractory castables is high, especially if the future trend is considered. Already today, refractory castables have to resist steadily exacerbated working conditions with respect to temperature and corrosion, because of increasing efficiency of today’s high temperature production processes. The refractory producers have identified this. The reduction of the cement content in refractory castables (LCC to ULCC to NCC) to reach these requirements is already applied but is not a general solution for a material improvement. The systematic investigation with respect to the cement content and the water to cement ratio is a neglected connection.