Air Classifiers

How to Choose the Right Air Classifier or Air Classifying Mill (ACM) | UK & EU

Choosing between an air classifier and an air classifying mill is less about brand or size and more about what problem you’re trying to solve: separation, grinding, or both—under real production conditions.

Below is the practical framework UK & EU manufacturers use to choose correctly the first time.

Step 1: Decide Whether You Need Grinding, Separation, or Both

This is the most important question.

If your material is already milled but the particle size distribution is too wide, inconsistent, or out of spec, you likely need a standalone air classifier.

If your material still needs size reduction and tight PSD control, an air classifying mill (ACM) is usually the smarter choice.

In short:

• Classifier = separation only

• ACM = grinding + separation in one system

Misidentifying this step is the most common (and expensive) mistake.

Step 2: Define the Required Cut Point and PSD Sharpness

Air classifying technology excels when top-cut control matters.

You should clearly define:

• Target cut size (e.g. d97 or d99)

• Acceptable fines content

• How tight the PSD must be batch to batch

Air classifiers and ACMs allow cut point adjustment via airflow and rotor speed, making them ideal for processes where specifications may evolve over time.

If you need sub-micron control, jet milling may be more appropriate. If consistency and yield are the priority, air classification is often the better tool.

Step 3: Evaluate Material Behaviour (Not Just Particle Size)

Material properties strongly influence system selection.

Consider:

• Is the material brittle or friable?

• Is it abrasive?

• Does it smear, melt, or soften with heat?

• Is it hygroscopic or sticky?

Brittle, dry materials are ideal for both classifiers and ACMs. Sticky or heat-sensitive materials may require cooling, conditioning, or alternative milling upstream.

This is where experience matters more than datasheets.

Step 4: Throughput vs Control

Air classifying systems scale well, but there is always a balance.

Ask:

• Is this R&D, pilot, or production?

• Is throughput more important than ultra-tight PSD?

• Will multiple SKUs run on the same system?

ACMs are excellent when consistent output and throughput must coexist. Standalone classifiers are often chosen when yield optimisation and fine control matter more than speed.

Step 5: Integration With Existing Equipment

Your current process matters.

Choose a standalone air classifier if:

• You already have a jet mill, pin mill, or hammer mill

• You want to improve yield without replacing equipment

• You need flexible classification downstream

Choose an ACM if:

• You want a compact, single-step solution

• You are designing a new line

• You want to avoid multi-stage milling complexity

Many UK manufacturers start with classifiers, then move to ACMs as production volumes grow.

Step 6: Wear, Maintenance, and Cleanability

For abrasive or regulated applications, design details matter.

Look for:

• Wear-resistant linings and rotors

• Tool-less or quick-access designs

• Sanitary construction where required

• Predictable maintenance intervals

Systems from DP Pulverizers are engineered with serviceability in mind—because downtime is usually more expensive than capital equipment.

Step 7: Compliance and Safety (Non-Negotiable in the UK & EU)

Your final selection must align with:

• CE and UKCA requirements

• ATEX zoning (if applicable)

• Dust containment and explosion mitigation

• GMP or hygienic design expectations

Choosing a compliant system from the start avoids costly retrofits and revalidation later.

Quick Decision Guide

Choose a Standalone Air Classifier when:

• Grinding is already complete

• PSD correction is the goal

• Yield optimisation matters

• Flexibility across products is required

Choose an Air Classifying Mill (ACM) when:

• Grinding and classification are both required

• Space and system simplicity matter

• Consistent PSD must be achieved in one pass

• Energy efficiency is important

The Practical Reality

The “best” air classification system is the one that:

• Meets your particle size spec reliably

• Integrates cleanly with your process

• Scales with your production needs

• Stays compliant as regulations tighten

Air classification is not about separating particles—it’s about controlling outcomes.

Air Classifier vs Air Classifying Mill (ACM) vs Jet Mill vs Pin Mill

How to Choose the Right Milling Technology | UK & EU

When manufacturers search for milling equipment, they’re rarely asking “What machine is best?”
They’re really asking: Which technology solves my problem with the least risk, waste, and compromise?

This guide compares the four most commonly confused technologies—air classifiers, air classifying mills, jet mills, and pin mills—so UK & EU manufacturers can make confident, process-driven decisions.

Air Classifier

Best for: Particle size separation without grinding

An air classifier does not reduce particle size. It separates particles based on size, shape, and density using airflow and centrifugal forces.

Choose an air classifier when:

• Material is already milled

• PSD is too wide or inconsistent

• Over-grinding must be avoided

• Yield improvement is the priority

• Screens are clogging or unreliable

Typical role in the process:

Quality control and yield optimisation

Air classifiers are often paired with jet mills, pin mills, or hammer mills as a downstream refinement step.

Air Classifying Mill (ACM)

Best for: Grinding + classification in one controlled step

An ACM combines mechanical grinding with internal air classification. Oversized particles are automatically rejected and re-ground until they meet spec.

Choose an ACM when:

• You need fine grinding and tight PSD

• You want a compact, single-stage solution

• Energy efficiency matters

• Over-grinding must be controlled

• Consistent output is critical

Typical role in the process:

Primary milling with built-in quality control

ACMs are extremely popular in food, chemicals, minerals, and pharmaceutical processing across the UK & EU.

Jet Mill

Best for: Ultra-fine and sub-micron grinding with minimal heat

Jet mills use high-velocity gas (air or nitrogen) to create particle-on-particle collisions—no mechanical grinding tools.

Choose a jet mill when:

• Sub-10 micron or sub-micron sizes are required

• Heat must be minimised

• Product purity is critical

• Contamination cannot be tolerated

• Inert gas or ATEX operation is required

Typical role in the process:

High-precision micronisation

Jet mills are common in pharmaceuticals, battery materials, advanced ceramics, and high-value R&D applications.

Pin Mill

Best for: Fine grinding with high throughput and simplicity

Pin mills use high-speed rotating pins to apply controlled impact and shear.

Choose a pin mill when:

• Fine grinding (not sub-micron) is required

• Throughput matters

• Operating simplicity is important

• De-agglomeration is needed

• Energy and operating cost must be controlled

Typical role in the process:

Efficient, repeatable fine grinding

Pin mills sit comfortably between hammer mills and jet mills in terms of precision and complexity.

Side-by-Side Decision Logic (Plain English)

• Need separation only? → Air Classifier

• Need grinding + separation? → ACM

• Need ultra-fine, heat-free micronisation? → Jet Mill

• Need fine grinding with high throughput? → Pin Mill

Why Processes Often Use More Than One

Modern UK & EU plants rarely rely on a single machine.

Common combinations include:

• Jet mill + air classifier (precision + yield)

• Pin mill + air classifier (throughput + control)

• ACM as a standalone solution

• Pre-mill + jet mill for staged size reduction

The smartest systems are designed around material behaviour, not marketing labels.

Choosing the Right Technology the First Time

The right choice depends on:

• Target particle size and PSD

• Heat sensitivity and material behaviour

• Throughput requirements

• Regulatory and safety constraints

• Integration with upstream and downstream processes

This is where experience matters more than brochures.

PerMix UK supports air classification and milling systems manufactured by DP Pulverizers, engineered to work as part of complete, compliant, and scalable processing lines across the UK and Europe.

The Big Picture Takeaway

Grinding makes particles smaller.
Classification decides which particles are acceptable.

The best milling systems do both intelligently, with as little wasted energy and product as possible.