What are the benefits of densified microsilica?

As we know, microsilica, also known as silica fume, is a by-product of ferrosilicon and silicon metal smelting, and is also referred to as reactive silica fume. It is collected by environmental protection equipment. Its initial bulk density is only 150-200 kg/m³, which leads to high transportation costs. For example, a 60-ton railway wagon can only carry about 18 tons of undensified microsilica, making transportation costs for the product sometimes account for up to 50% of its selling price. Therefore, densified microsilica is the best method to reduce costs. To lower transportation expenses, many microsilica manufacturers now use densification technology. Companies in countries such as Canada, Sweden, the United States, and Norway supply densified microsilica to ready-mix concrete companies or microsilica concrete batching plants. This method offers lower transportation costs, dust-free and convenient handling, improved working conditions, ease of pumping, and a high degree of mechanization.

Densified microsilica facilitates concrete mixing without affecting its flowability. During concrete production, researchers have found that using densified microsilica promotes more uniform mixing and enhances the overall performance of concrete. As a result, densified microsilica is increasingly widely used in concrete and other building material products. Undensified microsilica is primarily used in fields such as refractory materials or coatings.

Densification technology for microsilica was originally mastered by only a few developed countries, such as Norway's Elkem. They sold complete sets of equipment to China at very high prices. Currently, Chinese technical personnel, through research, experimentation, and trials, have also produced equipment with the same effect, achieving good operational results. Due to localization, costs have been significantly reduced, enabling the widespread adoption of this technology.

Densified microsilica is spherical, with its bulk density increasing from about 0.2 t/m³ for the raw powder to 0.3–0.6 t/m³. This can reduce packaging and transportation costs by approximately 30–60%. The handling efficiency of densified microsilica is greatly improved, storage space and land requirements are reduced, it is suitable for automated production, and on-site feeding no longer generates dust, thereby improving labor conditions and the environment in concrete production.