High-alumina cement, also known as aluminate cement, is a special cement with calcium aluminate (CaAl₂O₄) as the main mineral component. Its raw materials are mainly bauxite and limestone, which are ground after high-temperature calcination. Compared with ordinary silicate cement, high-alumina cement has higher heat resistance, corrosion resistance and early strength, so it is widely used in some special projects.

1. Characteristics of high-alumina cement
Good early strength: high-alumina cement has a fast hydration reaction rate, and can usually reach the strength of ordinary cement in 3 days or even 7 days within 24 hours. It is suitable for projects that require rapid demolding or rush construction.

Strong high temperature resistance: its structure is still stable at high temperature, suitable for high temperature environment or as a refractory material.

Strong corrosion resistance: It has good resistance to acids, alkalis, sulfates, etc., and is suitable for chemical environments or marine engineering.

Controllable setting time: fast initial setting, relatively short final setting time, and the proportion and construction rhythm must be mastered during construction.

2. Main uses
Refractory materials: commonly used for casting refractory bricks, furnace linings, cement kilns, boilers and other high-temperature equipment.

Chemical and corrosive environment engineering: such as acid-base pools, sewage treatment pools, marine structures, etc.

Emergency repair: due to its early strength characteristics, it is suitable for emergency repair and rush-to-schedule projects, such as airport runways and tunnel linings.

Special concrete: suitable for special concrete projects with high requirements for antifreeze and anti-corrosion.

3. Precautions
Although high-alumina cement has superior performance, its strength may have "conversion" problems after high-temperature maintenance or long-term storage, so it is necessary to pay attention to reasonable proportions and use environment. At the same time, it is not recommended to mix with ordinary cement to avoid adverse reactions.