Granulation Process and Molding Method of Ceramsite Filter Media
Briefly introduces the granulation process and molding method of ceramsite filter media.
Granulation Process and Molding Method of Ceramsite Filter Media
Granulation is a crucial process in shaping powdered raw materials into spherical particles, determining the particle size, shape, and strength of the final product.
Main Granulation Methods
Granulation Methods | Principles | Product Features | Applications |
Disc Granulation | Powder rolls into spheres in an inclined disc | Good spherical shape and uniform particle size | Suitable for filter media production (mainstream) |
Drum Granulation | Powder rolls into spheres in a rotating drum | High output, slightly less spherical shape | Suitable for building ceramsite |
Extrusion Granulation | Powder is extruded into strips and then cut into segments | Irregular shape, high strength | Suitable for small to medium scale production |
Roller Granulation | Powder is extruded by rollers | Regular shape, high strength | Suitable for medium scale production |
Disc Granulation (Mainstream Process)
Parameter Control:
Disc Rotation Speed: 10-20 rpm
Tilting Angle: 45-55°
Water Spray Volume: 15%-25%
Granulation Time: 5-15 minutes
Advantages: Good sphericity, controllable particle size; Disadvantages: Limited single-machine output.
Can produce products with a particle size of 0.5-25mm.
Key Factors Affecting Pelletizing Quality
Factors | Result |
Moisture content | 15%-25% is optimal; too low and pellets won't form, too high and they'll stick together |
Raw material fineness | Below 200 mesh, pellets form quickly and have good shape |
Granulation time | Moderate time results in dense pellets; too long and the particles will be too large |
Binder | Water glass/bentonite 1%-3%, improves green body strength |
Screening and Return Material
Post-granulation screening and grading: Fine powder is returned to the granulator, qualified granules enter the next process, and oversized particles are crushed and returned.
Summary
The granulation of ceramsite filter media can be summarized as follows: disc granulation produces good spherical shapes and high quality, and is the mainstream process for producing filter media. Moisture content (15%-25%), fineness (below 200 mesh), and granulation time are the three core control parameters. Standardized operation and strict screening are key to ensuring product quality.