Requirements for refractory products in cement kiln preheaters

The refractory structure in the cement kiln preheater is composed of two layers of materials. The outer layer is a kind of insulation material with low thermal conductivity and low strength. And the working surface is a kind of refractory material with certain strength and good resistance to alkaline material erosion. Refractory castables are often used in the complex shapes. Large area straight walls are prone to collapse due to the interaction of cold and heat, so anchoring measures should be considered. In other parts, refractory bricks are mostly used for masonry.

For primary and secondary preheaters, clay alkali resistant refractory products can be used to reduce the cost and improve the heat preservation effect.

For preheaters below three grades, the alkali resistant materials with a refractoriness of 1100℃or higher should be considered.

The strength of refractory products are depending on the speed of the gas stream, the higher speed of the air flow usually use higher strength refractory material.

In the case where the alkali content reaches a certain amount and it is possible to gradually enrich the parts, such as the four or five grade preheaters, the alkali-resistant material should be considered under the premise of satisfying the high refractoriness.