Vertical Roller Mill Solutions for Slag Micro Powder in Cement Plants

Vertical Roller Mill Solutions for Slag Micro Powder in Cement Plants

The cement industry is increasingly focusing on sustainable production methods, with slag micro powder playing a pivotal role as a supplementary cementitious material. Vertical roller mills (VRMs) have emerged as the most efficient technology for slag grinding, offering superior energy efficiency and product quality compared to traditional ball mills. This article explores the technical advantages and operational principles of VRM systems specifically designed for slag micro powder production in cement plants.

Challenges in Slag Grinding

Granulated blast furnace slag presents unique processing challenges due to its high hardness (Bond Work Index 18-23 kWh/t) and abrasive nature. Conventional grinding systems often face:

  • Excessive wear on grinding media
  • High specific energy consumption (50-60 kWh/t)
  • Inconsistent product fineness (400-600 m²/kg Blaine)
  • Frequent maintenance downtime
Vertical Roller Mill Technology
System Configuration
Component Function Key Feature
Grinding Table Material bed formation Wear-resistant alloy segments
Rollers Compressive grinding Hydro-pneumatic loading system
Separator Particle classification Dynamic rotor with adjustable vanes
Hot Gas Generator Drying & material transport Low-NOx combustion system
Process Flow
  1. Pre-crushed slag (<50mm) enters through airlock feeder
  2. Material spreads across rotating grinding table
  3. Hydraulic cylinders apply 50-150 bar grinding pressure
  4. Hot gases (250-300°C) dry and lift fines to separator
  5. Coarse particles recycle via external bucket elevator
Recommended Solutions

For slag micro powder production requiring D97 ≤ 5μm fineness, our SCM Ultrafine Mill series delivers exceptional performance:

Model Capacity (t/h) Power (kW) Fineness (mesh)
SCM800 0.5-4.5 75 325-2500
SCM1250 2.5-14 185 325-2500
SCM1680 5.0-25 315 325-2500

Key advantages for slag applications:

  • Energy Efficiency: 30% lower power consumption vs jet mills
  • Precision Classification: Vertical turbine classifier eliminates coarse particles
  • Durability: Tungsten carbide overlays on grinding components

For larger-scale operations requiring 30-325 mesh products, the LM Vertical Slag Mill series offers:

Model Capacity (t/h) Specific Surface (m²/kg) Moisture Reduction
LM220N 20-26 ≥420 15% → ≤1%
LM370N 90-110 ≥420 15% → ≤1%
Operational Benefits
Energy Savings

VRM systems demonstrate 40-50% lower specific energy consumption versus ball mills through:

  • Material bed comminution principle
  • Integrated drying with waste heat recovery
  • High-efficiency separator reducing recirculation
Quality Enhancement

The controlled grinding environment in VRMs produces slag powder with:

  • Narrower particle size distribution (PSD)
  • Higher 7-28 day activity index (95-110%)
  • Lower free lime content (<1%)
Case Study

A 5000t/d cement plant in Vietnam achieved these results after installing our LM220N slag mill:

Parameter Before After
Power Consumption 52 kWh/t 38 kWh/t
Production Rate 18 t/h 24 t/h
Product Fineness 380 m²/kg 430 m²/kg
Maintenance Interval 800 hours 3000 hours

Modern vertical roller mills represent the optimal solution for slag micro powder production, combining energy efficiency with precise particle size control. Our SCM Ultrafine Mill and LM Vertical Slag Mill series offer cement plants reliable, high-performance grinding solutions that maximize the value of slag while minimizing operational costs. With advanced features like intelligent control systems and wear-resistant designs, these mills ensure consistent product quality with minimal environmental impact.