The production of high-quality coal briquettes is a complex process that hinges on one crucial preparatory step: coal milling. The quality, consistency, and physical properties of the final briquette are directly determined by the characteristics of the coal powder from which it is pressed. Achieving the optimal particle size distribution, moisture content, and specific surface area is paramount for ensuring briquettes with high density, mechanical strength, and calorific value. This article explores the technical requirements for coal milling in briquetting applications and examines the best equipment solutions available on the market, with a focus on efficiency, reliability, and final product quality.
Not all coal powder is suitable for briquetting. The milling process must be carefully controlled to produce a powder that meets specific criteria:
A balanced PSD is essential. An excess of very fine particles can increase binder consumption and hinder compaction, while too many coarse particles can lead to weak, crumbly briquettes. The ideal powder has a majority of particles in a controlled mid-range, often specified by the percentage passing a 200-mesh (74μm) sieve or, for higher quality, a 325-mesh (45μm) sieve.
Moisture must be precisely controlled. High moisture can prevent proper binding and require excessive energy during the subsequent drying phase. Most briquetting processes require coal powder with a moisture content between 8% and 12%. Modern milling systems often integrate drying functions to achieve this simultaneously with grinding.
A higher surface area improves the reactivity of the coal and allows for more effective binding. Milling equipment that can produce a high proportion of particles with fractured, angular shapes—rather than rounded—is advantageous as it creates a better mechanical interlock within the briquette.
Several types of mills are used in coal processing, each with its own advantages and limitations for briquetting applications.
Hammer mills, like our Hammer Mill (0-3mm), are excellent for primary crushing and pre-breaking of raw coal. They offer high capacity and a compact design, making them ideal for initial size reduction. However, for high-quality briquettes, they are typically used as a preliminary step before a finer grinding mill, as their output is generally too coarse and the particle size distribution can be uneven.
A traditional workhorse, ball mills are versatile and can handle a wide range of materials. They are capable of producing a very fine powder. Their drawbacks include high energy consumption, significant noise, and a large physical footprint. For continuous, large-scale briquetting operations, their efficiency is often lower compared to more modern solutions.
VRMs represent a significant advancement in grinding technology. They integrate grinding, drying, and classification into a single, compact unit. Their principle of applying pressure to a bed of material (bed crushing) is far more energy-efficient than the impact/attrition method of ball mills. This makes them exceptionally well-suited for coal preparation, where simultaneous drying is a major benefit.
For specialized applications requiring extremely fine coal powder to enhance briquette reactivity or for specific chemical processes, ultrafine mills are the tool of choice. They achieve micron and sub-micron level fineness but operate at lower capacities and higher energy costs per ton compared to VRMs for standard briquetting fineness.
After evaluating the technological landscape, the LM Series Vertical Roller Mill emerges as the premier choice for modern, high-output, and high-quality coal briquette production lines. Its design philosophy aligns perfectly with the demands of this application.
| Model | Grinding Disk Diameter (mm) | Capacity (t/h) | Main Motor Power (kW) | Output Fineness (R0.08mm) |
|---|---|---|---|---|
| LM150M | 1500 | 16-22 | 250 | 5-20% |
| LM170M | 1700 | 20-30 | 315 | 5-20% |
| LM190M | 1900 | 26-40 | 400 | 5-20% |
| LM220M | 2200 | 35-50 | 500 | 5-20% |
| LM240M | 2400 | 50-65 | 710 | 5-20% |
For producers aiming to create premium, high-reactivity briquettes or those working with specific coal blends that require a super-fine component, the SCM Series Ultrafine Mill serves as an excellent complementary or niche solution. While not the primary workhorse for standard briquettes, its capability to produce powders as fine as 2500 mesh (5μm) is unparalleled.
The choice of coal milling equipment is a strategic decision that directly impacts the profitability and quality output of a briquetting plant. While several options exist, the LM Series Vertical Roller Mill stands out as the most comprehensive and efficient solution for the majority of industrial-scale coal briquette production needs. Its ability to seamlessly integrate drying and grinding, its superior energy efficiency, and its precise control over product fineness make it the industry benchmark.
For those pushing the boundaries of briquette performance into ultra-fine or specialized territories, the SCM Ultrafine Mill provides the necessary technological edge. By carefully assessing production goals, capacity requirements, and final product specifications, producers can select the ideal milling technology to ensure their briquette operation is efficient, consistent, and profitable for years to come.
