The sintering of refractory materials is to pre - burn some raw materials into mature materials, to crush them and to sifting them, and then mix them with raw materials in a certain ratio, and then form, dry and burn them. The purpose of raw material prefiring is to burn out the water, organic impurities and sulphate decomposed gases to reduce the burning shrinkage of the products and to ensure the accuracy of the shape of the products. The raw material needs to be sieved after crushing and grinding, because the billet is graded by different granularity, and the compact body can be obtained with the most compact accumulation.
In order to homogenate the ingredients and particles of various raw materials and clinker, mixing should be carried out and the binder should be added to enhance the bonding strength of the billet. If aluminum silicate billet is added into clay, magnesia billet is added to sulfite pulp waste liquid, silicon billet is added lime milk and so on. According to the amount of water content of the billet, it can be molded by semi dry (about 5% moisture), plastic molding (about 15% moisture) and grouting (about 40% moisture). Then dry and burn.