Improved additives for high purity low cement castable systems

Many types of organic molecules that are used as de? occulants in refractory castables are derivates from developments for the building industry with either Portland cement or mixed binder systems consisting, e.g., of Portland cement, Calcium Aluminate cement and Calcium Sulphate. Only few products have been developed which o t specio cally to pure Calcium Aluminate cements. Two new Polycarboxylate Ethers, Peramin ® AL200 and Peramin ® AL300 will be presented in this paper which are molecules tailor-made to de? occulate high purity alumina / alumina spinel castables. Peramin ® AL de? occulants provide the desired placing properties of these castable systems. Mixing water can be reduced to a minimum to provide castables with an excellent self-? owing and vibratable consistency. The rapid wet-out during mixing, predictable and sustained ? ow during placing, and effective de-airing during consolidation will be demonstrated. In addition, by using these additives either singly or in combination, depending on the ambient conditions, it is possible to achieve the required hardening proo le without the addition of classical accelerators. Peramin ® AL additives tailor-made for refractory castables that contain high quality 70 %. Calcium Aluminate cements like Secar ® 71 and Secar ® 712 bring improved quality to the installed castable, and ultimately,