Advanced Aluminium Scrap Sorting Machine with Eddy Current Separators, LIBS, and

Of course. Here is a detailed overview of aluminium sorting equipment used in recycling facilities, from basic to advanced technologies.

The goal is to separate aluminium from other materials (like plastics, glass, and other metals) and then separate different aluminium alloys from each other, as alloy purity determines value.

Before specific aluminium sorting, material must be prepared.

• Shredders: Reduce the size of scrap (e.g., cars, siding, window frames) for easier handling and sorting.
• Shears & Balers: Process larger, lighter aluminium scrap like UBCs (Used Beverage Cans) into dense bales for efficient transport and processing.
• Trommel Screens: Rotating drums that separate materials by size, removing dirt and small contaminants.

This is the highest-value step, separating 6061 alloy from 3003 alloy, etc. This is critical for producing high-quality wrought aluminium alloys.

• Laser-Induced Breakdown Spectroscopy (LIBS):
  • The gold standard for alloy sorting. A high-powered laser ablates a tiny spot on the metal piece, creating a plasma. The light from this plasma is analyzed by a spectrometer to determine the exact elemental composition (Mg, Si, Cu, Mn, etc.).
  • Application: Ultra-high-purity sorting of aluminium chips, turnings, and fragmented scrap. Essential for aerospace and automotive alloy remelting.
• X-Ray Fluorescence (XRF):
  • Emits X-rays that excite atoms in the metal, which then emit secondary (fluorescent) X-rays characteristic of each element.
  • Application: More common for larger pieces or hand-held units for quality control. Slower for high-throughput stream sorting compared to LIBS.

A modern plant integrates several pieces of equipment into a line:

1. Shredding: Scrap is shredded into small, uniform pieces.
2. Screening: Removes fine dust and undersized material.
3. Magnetic Separation: Removes ferrous metals (steel, iron) using a powerful magnet.
4. Eddy Current Separator: Ejects all non-ferrous metals (aluminium, copper, brass, zinc) into a separate stream.
5. Sensor Sorter (NIR/Color): May further clean the aluminium stream by removing any remaining contaminants or non-metal items.
6. Alloy Sorter (LIBS/XRF): The aluminium stream is fed into a LIBS sorter, which uses air jets to precisely separate pieces by alloy type into different bins.

• Artificial Intelligence (AI) & Deep Learning: Modern sensor sorters use AI to improve recognition accuracy over time, handling complex and contaminated streams better.
• Robotic Sorting: Robots equipped with vision systems (sometimes combined with spectroscopic sensors) are used for pre-sorting or quality control, picking specific aluminium items (like cans or radiators) from a conveyor.
• Hyper-spectral Imaging: Goes beyond standard NIR, using a wider spectrum of light for even more precise material identification.
• Increased Use of LIBS: As demand for high-recycled-content aluminium grows (especially in EVs), LIBS systems are becoming more cost-effective and widespread.

(Note: This is a representative list, not exhaustive)

• Tomra (Norway): Leader in sensor-based and laser sorting (including LIBS via their partnership with Unisensor).
• STEINERT (Germany): Major provider of magnetic, eddy current, and sensor-sorting solutions, including XRF and LIBS systems.
• Bühler Group (Switzerland): Offers advanced optical sorting solutions.
  
• Eriez (USA): Known for magnetic and eddy current separators.
• MSS, Inc. (USA): Specializes in optical sorters and AI-powered systems.
• CP Manufacturing (USA): Provides integrated recycling systems, including eddy currents.

In summary, recycling aluminium starts with eddy currents for bulk recovery and advances to sensor-based and LIBS technology for creating high-purity, alloy-specific streams that maximize both recycling rates and economic value.