Introduction to Heat-resistant Concrete

Heat-resistant concrete is a special concrete that can withstand high temperatures for a long time. It is mud made of refractory aggregates, cementitious materials (sometimes with mineral admixtures or organic admixtures), and water in a certain proportion. Refractory products with a certain strength are obtained by pounding or vibrating into shape, hardening, curing, and drying.

Bauxite, waste refractory bricks, blast furnace slag, etc. are usually used as aggregates, and alumina cement, Portland cement, phosphoric acid, and water glass are used as cementing materials.

Heat-resistant concrete is divided into many types according to the different aggregate materials and cementitious materials. Their compositions are different, their properties are different, and therefore their scope of use is also different. This kind of refractory product has the following advantages compared with refractory bricks:

1. Strength develops rapidly at room temperature and does not decrease at operating temperature.

2. It does not need to be fired before use, which reduces the complex process of making refractory bricks. The preparation process is simple and can be cast into various shapes on-site.

3. It can reduce the joints of masonry bricks, simplify the structure, and simplify the brick type, thus innovating the masonry work and speeding up the construction.

Heat-resistant concrete has been used in coke ovens for many years. It is mainly used as riser pipe and furnace door lining bricks, furnace roof track sleeper bricks to replace clay bricks, and is also used as coke oven roof paving. The ingredients vary depending on the parts used. Although the trial time of heat-resistant concrete in coke ovens is not long, it has shown some advantages, but there are also some shortcomings, such as the softening temperature under load is not high enough, and there is delamination and spalling during use.