WHITE CEMENT

White cement is a type of special cement, belongs to decoration cement. In general, Portland cement is greyish-green, as the name suggested, white cement is white. The chemical requirements of white cement are generally the same as Ordinary Portland Cement except that the maximum iron oxide content is restricted to less than 1% and the requirement for loss on ignition is not applicable. White Portland Cement is manufactured from raw materials having very little iron and magnesia, primarily to improve its whiteness. In the cement manufacturing process, in order to avoid the mixing of colored impurities, calcination of white cement plant mostly use natural gas or heavy oil as fuel.

White Portland Cement has essentially the same properties as gray cement, except for color. It is readily available throughout North America. The color of white cement is determined by its raw materials and the manufacturing process. Metal oxides, primarily iron and manganese, influence the whiteness and undertone of the material.

After adding pigments, white cements produce clean, bright colors, especially for light pastels.

Many different colors of concrete can be created, and just like with paint, two or more pigments can be combined to achieve a wide range of colors. An even greater variety of decorative looks can be achieved by using colored aggregates and varying the surface finish treatment or texture.

Mix designs for white or colored concrete are formulated based on each ingredient’s effect on concrete color:

• Type and color of cement

• Type and dosage of pigment

• Type and dosage of admixtures

• Type, gradation, color, and cleanliness of fine and coarse aggregates

• Consistent proportions, especially maintaining a uniform water-cement ratio

A key advantage of using white cement for decorative and architectural concrete is that it provides a neutral tinting base and consistent color results. Every color option is possible with it, from pure whites to bright and pastel colors.

hite Cement VS Portland cement

Similarity

Two are silicate cement, their cement raw materials include calcareous materials and salic materials, all materials are calcined by cement rotary kiln into cement clinker, add gypsum and admixture into clinker, which is grounded into white cement or Portland cement.

Hydration products are basically same, including hydrated silicate gel CSH, Ca (OH) 2 etc.

Physical and mechanical performance: strength, setting, rheological property, durability and others. Apply for decoration cement and structural cement.

Difference

High requirement for white cement manufacturing process:

• It is difficult to make high-quality white cement, which requires high-quality raw materials, strict grinding process and calcination.

• The white cement calcination temperature is higher.

Cement clinker mineral composition:

• White cement clinker contains 10-15% tricalcium silicate, 15-20% silicate minerals, basically no content of iron phase minerals, free calcium oxide generally used for Portland cement.

Admixture:

• White cement usually use limestone,

• Portland cement includes fly ash, slag, and volcanic ash.

Fineness:

• The white cement is finer than Portland cement.

• The white cement manufacturing process is similar to the Portland cement manufacturing process, so we introduce the factors that affect cement quality. Just like general cement manufacturing plant, the white cement manufacturing process can be generally divided into six steps:

Crushing:

Carbonate composition mostly uses primary crushing. Since a large number of dye oxides are concentrated in the fine particles, it is best to screen the fine particles before feeding them into the cement crusher. The clay ingredients are usually broken individually

Step -1 – Crushing (Jaw Crusher)

Cement Raw Materials Grinding:

Most of cement raw materials should be ground in the cement mill, and the grinding body can’t contain iron. As for the fineness, the white cement manufacturing process requires a finer size than that of Portland cement.

Step -2 – Cement Raw Material Grinding (Ball Mill)

Homogenization:

The homogenized raw materials only are promised to have heterogeneity at microscopic scales. The homogenization is very important to the white cement manufacturing process, its multi-component mixtures are generally more prone to segregation than raw materials used in the grey cement production lines.

Step -3 – Homogenization

Clinker Production:

There are various combinations of preheating and calcining systems, and which process is better depends on whether the existing plant needs to be rebuilt and how much the plant operators invest in the construction. The cement rotary kiln and cyclone preheater are the recommended group here.

Step -4 – Clinker Production (Rotary Kiln)

Cement Grinding:

Cement is made from cement clinker and thickening time control agents like gypsum or anhydrite. The gypsum generally uses jaw crusher, 90% of particles are less than 6mm and the biggest size is 80mm.

Step -5 – Cement Grinding (Grinding Plant)

Packing and Shipping:

The finished cement is generally stored in the cement silo, and for different uses, white cement can be packed or in bulk to transport to the desired place.

Step -6 – Packing/Shipping (Cement Silo & Packaging Machine)

The global white cement market reached a value of US$ 5.55 Million in 2020. Looking forward, IMARC Group expects the market to grow at a CAGR of around 6% during 2021-2026.

It is intended to prepare a Feasibility Report to install a White Cement production facility with an installed capacity of 36000 Tons / Year as a Green Field Project.