Production Process of Expanded Perlite

Production Process of Perlite

The production process of expanded perlite involves several key steps. The ore extracted from the mine is processed into sand with a certain particle size grading through mechanical crushing and vibrating screening. The expansion plant then selects and purchases the sand according to different purposes. The water content of the raw material mineral sand of perlite is generally 4-6%. To prevent the explosion of perlite, the ineffective water content should be removed before expansion. This ensures that it retains the water required for normal expansion. The production process of expanded perlite includes preheating and expansion, with extensive experiments showing that the best effect after expansion is achieved when the effective water content of expanded perlite is between 2.2 and 2.4%. Overall, these steps ensure that expanded perlite is produced safely and efficiently.

After preheating for 2-8 minutes at a temperature environment of 650-800 ℃, the moisture content of perlite ore sand will reach the expansion requirement. Following this, the mineral sand is evenly sprayed onto a flame with a temperature maintained at 1100-1200 ℃ through a feeding device. Due to this rapid heating, the mineral sand expands to 10-30 times its original volume and the expanded perlite particles become white or light gray. Inside, they possess a honeycomb-like structure, and a loose density of generally 40-80Kg/m3. Once separated by the cyclone separator with high-temperature gas, the expanded perlite enters the aggregate bin.