Magnesia iron spinel brick is made of composite spinel and high-purity magnesia, adding specific mineralizer, high-pressure molding and high-temperature sintering. It is a new generation of alkaline refractory with more technical content. It is mainly used in the firing zone of large dry process cement kiln.
Excellent structural flexibility and strong corrosion and permeability resistance to K2SO4, Na2SO4, NaCl and KCl alkali salts decomposed by cement materials.
High refractoriness under load and excellent thermal shock resistance make it suitable for the key parts of SP and NSP kilns which are of high kiln temperature, fast rotating speed, strong alkali erosion ability and heavy mechanical load. It can effectively prolong the service life of furnace lining and maintain low temperature on kiln barrel.
In the process of use, a layer of calcium iron or calcium aluminum iron oxide with high viscosity is formed on the hot surface of the brick, which improves the performance of hanging kiln skin and the firmness of kiln skin, and is suitable for protecting the lining brick and prolonging the service life.
High content of spinel is of high strength and excellent thermal shock resistance. At the same time, it can effectively resist the chemical corrosion of cement clinker liquid phase and alkali, sulfur and other gases.
Due to the inconsistency of thermal expansion between spinel and periclase during firing and cooling, the micro crack gap formed between them can buffer the stress impact caused by temperature change and avoid the brittle cracking of lining brick.