Material Composition and Production Process of Ceramsite Filter Media
A brief overview of the main material composition and production process of ceramsite filter media.
Material Composition and Production Process of Ceramsite Filter Media
Ceramsite filter media is made from clay, shale, fly ash, and other raw materials through high-temperature calcination. Its performance depends on the raw material ratio and process control.
Main Material Composition
Raw Material Type | Function |
Clay, Shale | Main framework, providing aluminosilicate matrix |
Fly ash, Coal gangue | Auxiliary raw materials, reducing costs and adjusting density |
Expanding agents (calcium carbonate, carbon powder, sawdust) | High-temperature decomposition produces gas, forming internal pores |
Binders (water glass, bentonite) | Improve green strength |
Fluorescent agents (feldspar, talc) | Lower sintering temperature |
Production Process Flow
Raw Material Processing: Crushing and grinding to below 200 mesh → Mixing according to the formula
Granulation and Forming: Feeding into a disc or roller granulator, rolling to form spheres while spraying water, particle size 0.5-25mm
Drying: Drying at 100-200℃, reducing moisture content to below 5% to prevent cracking during calcination
Calcination: High-temperature calcination at 1100-1300℃ to form a honeycomb-like porous structure (core process)
Cooling and Screening: After cooling, screening to obtain the finished product
Key Process Parameters
Parameters | Control Range | Impact |
Raw Material Fineness | Below 200 mesh | Too coarse, uneven porosity |
Pelletizing Moisture | 15%-25% | Too high, sticking; too low, no pelletizing |
Firing Temperature | 1100-1300℃ | Too low, insufficient strength; too high, surface vitrification |
Firing Time | 15-60 minutes | Too short, incomplete firing |
Summary
The performance of ceramsite filter media is determined by both the raw material ratio and the calcination process. High-quality ceramsite must possess uniform honeycomb pores, sufficient mechanical strength, and good chemical stability. Calcination temperature is a key factor in quality control.