The building materials industry is developing towards the direction of energy conservation, environmental protection, and safety, and the demand for building materials with excellent thermal insulation, fire resistance, and environmental protection performance is increasing. Diatomaceous earth powder (diatomite powder), as a natural, porous, and non-toxic mineral material, has become a new type of functional additive in the building materials industry. It can be added to wallboards, coatings, mortars, and other building materials to improve their thermal insulation, fire resistance, and sound insulation performance, while meeting the environmental protection requirements of modern buildings.
In wallboard production, especially in thermal insulation wallboards (such as gypsum wallboards, cement wallboards), diatomaceous earth powder can significantly improve the thermal insulation performance of wallboards. The porous structure of diatomite powder contains a large amount of static air, which has a low thermal conductivity (0.03-0.05 W/(m·K)). Adding 10-20% diatomaceous earth powder to the wallboard matrix can reduce the thermal conductivity of the wallboard by 20-30%. For example, the thermal conductivity of ordinary gypsum wallboard is about 0.15 W/(m·K), while that of gypsum wallboard added with 15% diatomaceous earth powder is reduced to 0.11 W/(m·K). This means that in the same building, using diatomaceous earth powder-added wallboards can reduce the heat loss in winter and heat gain in summer, thereby reducing the energy consumption of air conditioning and heating by 15-25%. A residential project in North China used interior and exterior wallboards added with diatomaceous earth powder. After one year of use, the average energy consumption of each household was 20% lower than that of nearby residential areas using ordinary wallboards, achieving good energy-saving effects.
In addition to thermal insulation performance, diatomaceous earth powder can also improve the fire resistance of wallboards. Diatomite powder is a non-combustible material with a melting point of more than 1600°C. Adding it to wallboards can increase the fire resistance limit of the wallboards. The fire resistance limit of ordinary cement wallboards is about 1 hour, while that of cement wallboards added with 15% diatomaceous earth powder can reach 1.5-2 hours, which meets the fire protection requirements of high-rise buildings. In the event of a fire, the diatomaceous earth powder in the wallboard can absorb a large amount of heat, slow down the spread of the fire, and reduce the release of toxic gases, providing more escape time for people.
In building coatings and mortars, diatomaceous earth powder can improve their sound insulation and moisture absorption performance. Interior wall coatings added with 3-5% diatomaceous earth powder can absorb part of the sound waves through their porous structure, reducing the indoor noise by 5-10 dB, creating a quieter living environment. At the same time, the porous structure of diatomite powder has good moisture absorption and release performance. It can absorb excess moisture in the air when the indoor humidity is high, and release the absorbed moisture when the humidity is low, keeping the indoor humidity at 40-60%, which is suitable for human living. A hotel in South China used interior wall coatings added with diatomaceous earth powder. After testing, the indoor humidity was stably maintained at 45-55% throughout the year, and the guests' satisfaction with the indoor environment increased by 30%.
Our diatomaceous earth powder for building materials has a variety of specifications to meet different application needs. For thermal insulation wallboards, we provide diatomite powder with a particle size of 100-300 mesh and a specific surface area of ≥150 m²/g, which can balance thermal insulation performance and mechanical strength; for interior wall coatings, we provide fine-grained diatomite powder (500-1000 mesh) with high whiteness (≥85), ensuring the smoothness and decoration effect of the coating film; for fire-resistant mortars, we provide calcined diatomite powder with high temperature resistance (calcination temperature 1000-1200°C), which can improve the fire resistance of the mortar. The main technical indicators of our products are: SiO₂ content ≥85%, Al₂O₃ content ≤6%, Fe₂O₃ content ≤2%, moisture content ≤3%, and bulk density 0.3-0.6 g/cm³.
In the production process, we pay attention to the compatibility of diatomaceous earth powder with building materials. For example, when producing diatomite powder for gypsum wallboards, we will modify the surface of the powder to improve its adhesion with gypsum, avoiding the problem of reduced mechanical strength of the wallboard due to poor compatibility. We also conduct a large number of compatibility tests with different building materials (such as cement, gypsum, latex paint) to ensure that the diatomaceous earth powder can be evenly dispersed in the building material matrix and play its due role.
In terms of quality assurance, our diatomaceous earth powder for building materials meets the national standards of China (GB/T 21690-2008《Diatomite for Building Materials》) and the European standard (EN 13055-1《Lightweight aggregates - Part 1: Specification for lightweight aggregates made from natural materials》). We have established a complete quality control system, from raw ore mining to finished product delivery, each link is strictly inspected. For example, the raw ore is sampled and tested every day to ensure that the SiO₂ content and impurity content meet the requirements; the finished product is tested for particle size, specific surface area, and moisture content, and only products that pass the test can be delivered.
