A cement mill (or finish mill) is a key piece of equipment in cement plants, used to grind clinker, gypsum, and other additives into fine cement powder. Below is a simplified diagram and explanation of a typical ball mill used in cement grinding:
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Cement Mill (Ball Mill) Diagram
*(Simplified Flowchart)*
“`
┌───────────────────────┐
│ Clinker + Gypsum │
│ (+ Additives, if any)│
└──────────┬────────────┘
↓
┌───────────────────────┐
│ Feed Hopper │
└──────────┬────────────┘
↓
┌───────────────────────┐
│ Grinding Chamber │ ←─── Steel Balls (Grinding Media)
│ (Rotating Drum) │ ←─── Liners (Protective Layer)
└──────────┬────────────┘
↓
┌───────────────────────┐
│ Separator │ ←─── Coarse particles recycled back
└──────────┬────────────┘
↓ (Fine Powder)
┌───────────────────────┐
│ Cement Silo │ (Storage)
└───────────────────────┘
“`
—
Key Components & Process Steps:
1. Feed Materials:
– Clinker (from the kiln), gypsum (~5% for setting control), and optional additives (e.g., limestone, slag).
2. Grinding Chamber:
– A rotating drum filled with steel balls or other grinding media.
– The material is crushed and ground into fine powder by impact and attrition.
3. Separator/Classifier:
– Separates fine cement particles from coarse ones.
– Coarse material is returned for regrinding (*closed-circuit system*).
4. Product Output:
– Fine cement powder (typically 15–45 µm particlize) is sent to silos for packaging/dispatch.
—
Types of Cement Mills:
1. Ball Mill: Traditional, with horizontal rotating chambers.
2. Vertical Roller Mill (VRM): More energy-efficient, uses rollers instead of balls.
3. Roller Press +