Energy-Saving Grinding
A vertical roller mill (VRM) that combines grinding, drying, and classification in a single compact unit — saving 20-30% energy versus ball mills. Capacities from 70 to 720 t/h, with integrated hot-gas drying for feed moisture up to 20%. The modern choice for dry-process cement plants.
Product Overview
The vertical raw mill — also known as a vertical roller mill (VRM) — is an advanced grinding machine that reduces cement raw materials (limestone, clay, marl, sand, iron ore) into fine raw meal using compression and shear between rotating grinding rollers and a stationary grinding table. Unlike a ball mill, which grinds by impact of tumbling media, the VRM grinds by bed compression — a fundamentally more efficient mechanism that consumes 20-30% less electrical energy per ton.
A key advantage of the VRM is its 3-in-1 functionality: grinding, drying, and classification occur simultaneously in a single machine. Hot gases from the preheater exhaust or a hot-air furnace (250-400°C) pass through the mill, drying feed with up to 20% moisture while grinding. An integrated dynamic separator (classifier) at the top of the mill continuously separates fine product from coarse particles, returning the coarse fraction for regrinding. This eliminates the need for separate drying equipment, external separators, and conveying systems — reducing building volume, civil works, and auxiliary equipment.
LIMING vertical raw mills are the preferred choice for new dry-process cement plants with capacities from 1,000 to 10,000 TPD. Their small footprint, low noise, and superior energy efficiency deliver rapid return on investment, while their ability to handle wet, sticky feed makes them versatile across diverse raw material conditions.
Key Benefits
Superior energy efficiency and compact design for modern dry-process cement plants.
Bed-compression grinding uses 20-30% less power per ton than ball mills. For a 5,000 TPD plant, this saves millions of kWh annually — paying back the higher capital cost in 2-3 years.
Compact vertical design occupies 50-70% less floor area than a ball-mill circuit. Lower building height and civil-works cost — ideal for greenfield and retrofit projects with limited space.
Hot preheater exhaust gas (250-400°C) dries feed moisture up to 20% while grinding — eliminating the need for a separate dryer and crusher-dryer. Reduces equipment count and energy use.
Integrated high-efficiency classifier ensures precise product fineness (80-90% passing 90μm) with narrow particle-size distribution. Adjustable rotor speed for instant fineness control.
Technical Data
Representative VRM models for cement raw material grinding.
| Model | Table Ø (mm) | Capacity (t/h) | Feed Size (mm) | Product Fineness (R90μm) | Motor Power (kW) | Weight (t) |
|---|---|---|---|---|---|---|
| TRM-17.4 | 1,740 | 70-90 | ≤50 | ≤12% | 800 | 43.8 |
| TRM-22.0 | 2,200 | 100-130 | ≤50 | ≤12% | 1,000 | 68.0 |
| TRM-25.0 | 2,500 | 140-180 | ≤60 | ≤12% | 1,250 | 95.0 |
| TRM-28.0 | 2,800 | 180-240 | ≤60 | ≤12% | 1,800 | 130.0 |
| TRM-32.0 | 3,200 | 240-310 | ≤70 | ≤12% | 2,400 | 175.0 |
| TRM-34.0 | 3,400 | 300-380 | ≤70 | ≤12% | 2,800 | 205.0 |
| TRM-36.4 | 3,640 | 350-440 | ≤80 | ≤12% | 3,200 | 245.0 |
| TRM-38.4 | 3,840 | 400-500 | ≤80 | ≤12% | 3,800 | 285.0 |
| TRM-41.4 | 4,140 | 480-580 | ≤80 | ≤12% | 4,200 | 340.0 |
| TRM-43.4 | 4,340 | 550-650 | ≤90 | ≤12% | 4,800 | 395.0 |
| TRM-45.4 | 4,540 | 620-720 | ≤90 | ≤12% | 5,400 | 485.0 |
* Specifications are for reference only. Actual capacity depends on material hardness, feed moisture, and fineness requirement. Contact LIMING for custom sizing.
How It Works
The vertical raw mill grinds material by bed compression between rotating rollers and a stationary grinding table. Hot gas simultaneously dries the feed, and an integrated dynamic separator classifies the product — all in one machine.
Frequently Asked Questions