Magnetic separator: industrial guide and application

Complete guide to the Lenoir-Mec industrial magnetic separator: technologies, sizing criteria and applications to secure your production lines.

In industry, metal impurities in a material flow can cause production stoppages, premature equipment wear or degraded product quality. The magnetic separator is designed to capture and extract these ferrous or non-ferrous elements in order to secure and optimise the process.

Used in recycling, food processing, quarrying, mining and plastics processing, magnetic separation both protects installations and allows recovered metals to be reclaimed. The choice of technology depends on the type of contaminant, the throughput, the particle size and the operating environment.

This guide helps you understand the different solutions available and identify the industrial magnetic equipment best suited to your application.

What is an industrial magnetic separator?

An industrial magnetic separator is designed to automatically extract metal particles present in a flow of solid or bulk materials. It uses the properties of the magnetic field to attract and retain ferromagnetic elements (iron, steel) or, depending on the technology used, also to separate certain non-ferrous metals such as aluminium.

Installed within a production process, it can be used at different stages: protecting a shredder, purifying a finished product, recovering reclaimable metals or improving the quality of a recycled material.

Its role is both technical and economic: limiting stoppages, reducing maintenance costs and improving the overall yield of the installation. Several technologies are suited to industrial constraints: overband magnet, magnetic drum, eddy current separator or high-intensity systems. The choice always depends on the characteristics of the processed flow and the objectives pursued.

Why integrate a magnetic separation solution into your process?

Protecting equipment and production continuity:

Metal parts in a material flow can cause significant damage: broken shredders, damaged conveyors, premature wear of extruders or crushers. By capturing ferrous elements upstream, magnetic separation reduces the risk of unplanned stoppages and extends machine service life.

Improving

product quality:

In food processing, plastics processing or chemicals, metal particles can compromise the compliance of a finished product. A correctly sized industrial magnetic system ensures a cleaner flow and meets manufacturers’ quality requirements and applicable standards.

Reclaiming ferrous and

non-ferrous metals:

In recycling, quarrying and mining, the recovery of ferrous and non-ferrous metals is a source of value. Efficient separation increases recovery rates, improves the quality of the sorted fractions and optimises the overall profitability of the site.

Technology

Target metals

Key advantage

Typical application

Permanent magnet overband magnet

Ferrous

Low maintenance

Recycling, quarrying

Electromagnetic overband magnet

Ferrous

Deep magnetic field

Recycling, quarrying

Eddy current separator

Non-ferrous

Improved accessibility for quick maintenance

Sorting plant

Magnetic drum

Ferrous

High processing capacity

Sorting plant, cement plant, foundry

High-intensity separator

Ferrous

High magnetic intensity

Chemical, pharmaceutical and mining industries

The main magnetic separation technologies

There are several magnetic separation technologies, each meeting specific constraints of throughput, particle size, environment and industrial objective. The choice always depends on the type of metal to be extracted and on integration into the process.

A — Permanent magnet overband magnet

Operating without a power supply, this permanent magnet overband magnet offers reduced maintenance and great ease of operation. It is suited to applications requiring continuous separation of ferrous metals with controlled energy costs.

B — Electromagnetic overband magnet

Electromagnetic overband magnets generate a deep magnetic field, ideal for processing flows with large material depths. Installed above a conveyor or at its end, the unit efficiently attracts and extracts ferrous contaminants.

C — Eddy current separator

The eddy current separator (ED-X) separates non-ferrous metals such as aluminium or copper. It is used in particular in sorting plants and recovery lines to improve the purity of the recovered fractions.

D — Magnetic drum

The magnetic drum provides automatic, continuous separation of ferromagnetic particles in bulk flows. Robust and largely insensitive to dusty environments, it is widely used in mines, quarries and recycling installations.

E — High-intensity separator

Designed to process weakly magnetic particles, this high-intensity separator is used in specific applications requiring greater separation precision.

How to choose the right magnetic separator?

The choice of an industrial magnetic separator cannot be standardised. Each installation has specific constraints that directly influence separation efficiency.

• Nature of the impurities: The first question concerns the type of metal to be extracted. Ferromagnetic particles (iron, steel) require a different technology from that used for non-ferrous metals such as aluminium or copper. The size, shape and proportion of metal impurities also influence system sizing.
• Throughput and particle size: The volume of materials processed (t/h) and the particle size determine the magnetic power required and the appropriate technology. A fine, homogeneous flow is not processed in the same way as a heterogeneous or bulky mixture.
• Installation configuration and environment: Available height, integration space, temperature, humidity, dust or abrasive conditions: these parameters determine the choice between permanent magnet, electromagnetic or specific system.

Sizing depends directly on the throughput and the characteristics of the processed flow. For example, a municipal solid waste flow processed at 150 t/h with a particle size greater than 50 mm will require different sizing from a flow of fine aggregates below 10 mm.

In which industrial sectors is magnetic separation used?

Industrial magnetic systems are used in many sectors where controlling metal contaminants is a technical and economic issue.

Recycling and waste recovery

In sorting plants and waste treatment installations, magnetic separators recover ferrous and non-ferrous metals in order to improve the quality of the reclaimed fractions. They help increase recovery rates and optimise the profitability of sorting lines.

Mining and quarrying

In mining and extractive environments, magnetic equipment protects crushers and shredders against tramp metal while, in some cases, contributing to the concentration of specific ores.

Food processing

Metal particles in a food product can lead to major non-conformities. Industrial magnetic equipment ensures process safety and contributes to compliance with quality requirements.

Plastics processing, chemicals and processing industries

In flows of raw or recycled materials, removing metal contaminants improves the quality of the final product and limits manufacturing defects.

In these demanding environments, regular checking of magnetic performance is essential to ensure efficient separation and secure the process over the long term.

FAQ: Magnetic separator

What is a magnetic separator?

A magnetic separator is a piece of industrial equipment designed to automatically extract metal particles present in the product. It works by creating a magnetic field capable of capturing ferromagnetic materials such as iron or steel and, depending on the technology used, can also separate certain non-ferrous metals. It is used to protect equipment, improve product quality or reclaim recovered metals.

What is the service life of an industrial magnetic separator?

The service life of an industrial magnetic separator depends on the technology used, the operating environment and the quality of maintenance, but some can exceed 20 years.

When should an eddy current separator be used?

The eddy current separator is used to extract non-ferrous metals such as aluminium or copper. It is particularly suited to sorting plants, recycling installations and recovery lines where the objective is to improve the purity of the recovered fractions.

How do you determine the right magnetic intensity?

The magnetic intensity depends on the type of metal to be extracted, the throughput and the pick-up depth. Appropriate sizing requires a complete analysis of the process to ensure optimal separation.

Does a magnetic separator work with wet materials?

Yes, but efficiency can vary depending on the particle size and moisture content. In some cases, moisture can encourage impurities to agglomerate, which affects magnetic capture. The choice of technology and the position in the process must then be adapted to actual operating conditions.

Industrial magnetic separation: optimise your performance

Each industrial site has specific constraints: nature of the material, throughput, site configuration, operating environment or performance objectives. A standard magnetic separator does not always guarantee optimal efficiency if it is not correctly sized.

An upstream analysis makes it possible to identify: the most suitable type of technology, the magnetic intensity required, the optimal position in the production line and the mechanical and electrical integration constraints.

Precise sizing ensures efficient separation, as well as fewer stoppages, better equipment protection and lasting optimisation of operating costs.

At Lenoir-Mec, we guide you towards the most suitable solution through a fully customised approach:
site analysis, sizing, commissioning, responsive follow-up and regular inspections.

In a competitive industrial environment, a poor choice of magnetic separation can cost thousands of euros every year in unplanned maintenance.
Our experts guide you towards a reliable and robust solution.

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