The difference between white portland cements and common cements:
1. White portland cement has high technical requirements and it is difficult to produce high-quality products.
The raw materials with high quality, strict grinding process, calcination process and bleaching process. The raw material is very poor in burnability. The calcination temperature is 100-150℃. There is no second air and third utilization. The contradiction between whiteness and strength is difficult to coordinate.
2. Different mineral compositions of clinker
White cement clinker tricalcium silicate is about 10-15% high, and the total amount of silicate minerals is 15-20%. There is basically no iron phase minerals, and free calcium oxide is usually higher than general cement.
3. Different mixtures
Limestone or dolomite are often used as admixtures for white cement, while fly ash, slag and pozzolanic ash are commonly used as admixtures for general cement.
4. Different fineness of cement
The fineness of white cement is obviously finer than that of common cement.
5. The performance differences of the parts
The trends of hydration heat, fluidity, setting time, shrinkage and brittleness are different.
White cement has excellent structural properties, because its calcium silicate content reaches 90% and the hardening body is mainly gel structure, so the structure is compact, stable, and it has good water resistance, long service life. At the same time, it has super high strength and does not shrink.