Grinding barite (barium sulfate, BaSO₄) into a fine powder involves several steps to achieve the desired particle size and quality. Here’s a comprehensive guide:
1. Crushing (Pre-Grinding)
– Primary Crushing: Use a jaw crusher or hammer crusher to break large barite lumps (typically 10–50 cm) into smaller pieces (~1–5 cm).
– Secondary Crushing: Further reduce the size with a cone crusher or impact crusher to ~1–10 mm for easier grinding.
2. Grinding Process
Choose the appropriate grinding equipment based on the required fineness:
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# Common Grinding Machines for Barite:
– Raymond Mill
– Fineness: 80–325 mesh (0.044–0.18 mm)
– Suitable for medium-fine powder production (common in drilling, paint, and coatings).
– Low energy consumption, widely used in barite processing.
– Ultrafine Grinding Mill (HGM Series)
– Fineness: 325–2500 mesh (5–74 μm)
– Used for high-value applications like plastics, rubber, and pharmaceuticals.
– Equipped with classifiers for precise particle control.
– Ball Mill
– Fineness: Adjustable (typically up to 200 mesh).
– Wet or dry grinding options; often used with a classifier for finer products.
– Vertical Roller Mill
– Energy-efficient, produces powder in the range of 80–400 mesh.
# Key Parameters for Grinding:
– Feed size: ≤25 mm (optimized for mill efficiency).
– Moisture content: <1% (drying may be needed if too high).
– Grinding aids (optional): Dispersants like sodium polyacrylate can improve efficiency.
3. Classification & Separation
– Use an air classifier or vibrating screen to separate fine powder from coarse particles.
– Coarse material is returned for regrinding ("closed-circuit grinding").
4. Surface Modification (Optional)
For specialty applications (e.g., plastics, composites), barite may be c.jpg)
ed with stearic acid or silane to improve compatibility.
5. Drying
If wet grinding is used, a dryer (rotary or fluidized bed) removes moisture to <0.2%.
6. Packaging & Storage
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