Scrap cables and wires are one of the most valuable sources of recyclable metals in the modern waste stream. Inside a typical discarded power cable, communication wire, or automotive harness, you will find a mix of conductive metals—primarily copper and aluminum—protected by plastic, rubber, or even steel armor. Recovering these metals efficiently requires more than brute force. A well-designed cable recycling equipment uses a sequence of mechanical and physical separation techniques to isolate each material stream with minimal loss and contamination. Understanding how a granulator handles different metal types can help recycling operators choose the right equipment, configure it correctly, and maximize the value of every ton of scrap cable they process.
The Metal Mix Found in Scrap Cables
Before examining the separation process, it is useful to recognize what a granulator is actually asked to process. Copper remains the dominant metal in most electrical cables because of its excellent conductivity. Aluminum appears in overhead lines, large-diameter power cables, and some automotive wiring where weight savings matter. Steel or iron may be present as armoring, structural reinforcement, or fasteners such as staples and connectors. Finally, every cable contains some form of insulation—PVC, PE, rubber, or XLPE—that must also be removed and collected as a separate product stream.
Because these materials differ in density, conductivity, magnetic behavior, and particle size after crushing, a granulator line can exploit these physical differences to sort them automatically.
Stage One: Pre-cutting and Manual Sorting
The first step in any efficient cable recycling operation is preparation. Long, tangled cables can wrap around rotating shafts and jam the feeding system. Pre-cutters or scrap cable strippers reduce the material to manageable lengths. At this stage, operators also remove visible contaminants such as large connectors, wooden reels, and oily rags. Sorting cables by metal type before feeding improves final purity. For example, mixing copper and aluminum cables in the same batch can reduce separation accuracy because the two metals behave differently in air separators. Batch processing by material type allows operators to optimize screen sizes, airflow rates, and vibrating table settings for each run.
Stage Two: Crushing and Liberation
Once prepared, the cables enter the main crusher of the granulator. High-speed rotating blades shear the material into small granules, typically in the range of 1 to 5 millimeters. The goal is to liberate the metal from the insulation without over-grinding. If the particles are too fine, metal loss increases. If they are too large, plastic fragments remain attached to metal pieces and reduce purity. Modern cable recycling machine units use adjustable blade gaps and interchangeable screens to control output particle size based on the input material. San Lan Technologies offers cable recycling machines with capacity ranging from 100 kg/hour to 1200 kg/hour, allowing operators to match throughput to their daily volume.
Stage Three: Magnetic Separation of Ferrous Metals
After crushing, the mixed granules pass over a magnetic separator or drum magnet. This is the simplest and most reliable separation step. Ferrous metals such as steel armor, iron staples, and stray hardware are attracted to the magnetic field and pulled out of the stream. Removing iron early protects downstream equipment from abrasion and prevents iron contamination in the final copper or aluminum product. The collected ferrous scrap can be sold directly to steel mills, creating an immediate revenue stream.
Stage Four: Air Separation of Copper, Aluminum, and Plastic
With ferrous metals removed, the remaining stream contains copper granules, aluminum granules, and plastic fragments. The core separation principle relies on density differences. Copper has a density of approximately 8.9 g/cm³, aluminum about 2.7 g/cm³, and most cable plastics fall below 1.5 g/cm³. In a dry-type cable recycling machine, an air separator or air classifier blows upward through a vibrating deck. Lighter plastic particles are carried away by the airflow and collected in a cyclone or bag filter. Heavier metal granules settle and fall into a separate collection bin.
For operations processing mostly copper wire, this step alone can achieve 96 to 98 percent copper purity. However, when aluminum cables are included in the mix, additional care is needed. Because aluminum is lighter than copper but heavier than plastic, airflow speed and vibration amplitude must be adjusted to prevent aluminum from being misdirected into either the plastic stream or the copper stream. Running mixed copper and aluminum cables without adjustment will produce contaminated outputs. The practical solution is either to sort cables by metal type before processing or to add a secondary electrostatic separator.
Stage Five: Wet Separation for Fine or Complex Materials
Some cable recycling plants use wet separation instead of or in addition to dry air separation. In a wet-type system, granules are fed into a water-based density separation tank. Copper sinks, plastic floats, and aluminum settles at an intermediate level. Wet separation can achieve slightly higher purity for very fine wires or heavily contaminated materials. However, it requires wastewater treatment, water recycling infrastructure, and drying equipment for the final metal products. For many scrap yards and mid-sized recycling businesses, dry separation remains the preferred method because it avoids water consumption, simplifies maintenance, and keeps operating costs lower.
San Lan Technologies manufactures both dry-process and wet-process cable recycling equipment, giving customers flexibility to choose a configuration that matches their local environmental regulations and material characteristics.
Stage Six: Electrostatic and Vibrating Table Separation
Even after air separation, a small amount of plastic dust or fine metal particles may remain in the product stream. A vibrating table uses controlled vibration and gentle airflow to further refine the separation. Because copper is denser than plastic, the two materials move differently across the vibrating surface and can be split into separate discharge chutes.
For applications requiring maximum purity, an electrostatic separator adds another layer of precision. This device applies an electric charge to the mixed particles. Conductive metals such as copper and aluminum discharge quickly and follow a different trajectory than non-conductive plastics under an electrostatic field. The result is an exceptionally clean copper fraction suitable for direct smelting or sale at premium prices.
Stage Seven: Dust Collection and Environmental Control
Throughout the crushing and separation process, fine dust is generated. A pulse-jet bag dust collector or cyclone separator captures these particles before they escape into the workshop. This protects worker health, maintains product cleanliness, and ensures compliance with environmental standards. Modern cable recycling equipment integrates dust collection as a standard feature rather than an optional accessory.
Optimizing Separation for Different Metal Types
To get the best results from a cable recycling granulator, operators should follow a few practical guidelines. First, sort input material by metal type whenever possible. Processing copper cables in one batch and aluminum cables in another allows precise machine calibration. Second, adjust the crusher screen size to match the cable diameter. Thin communication wires require finer screens than thick power cables. Third, monitor airflow in the separator regularly. Seasonal changes in temperature and humidity can affect air density and separation efficiency. Fourth, keep blades sharp and ｒｅｐｌａｃｅ worn screens promptly. Dull blades tear rather than cut, producing irregular particles that separate poorly.
Choosing the Right Cable Recycling Equipment
Not every recycling operation needs the same machine. Small scrap yards and startup businesses may prefer a compact cable recycling machine with dry separator, processing 100 to 200 kg per hour. These units have a small footprint, simple operation, and lower capital investment. Medium-sized facilities handling mixed industrial scrap often choose machines in the 300 to 600 kg/hour range, offering a balance between throughput and separation precision. Large recycling plants processing bulk cable from demolition or utility projects may require high-capacity cable recycling plant equipment rated at 1000 kg/hour or more.
San Lan Technologies has been manufacturing copper wire recycling machine and cable recycling solutions since 2007. The product range includes compact granulators with dry separators, wet-separation cable recycling plants, scrap cable strippers for pre-processing large-diameter wires, and complete turnkey recycling lines. All machines are built with wear-resistant steel blades, adjustable crushing gaps, and integrated dust control systems. With customers in more than 21 countries, San Lan provides not only equipment but also technical support, installation guidance, and spare parts supply.
Conclusion
A wire and cable recycling granulator handles different metal types by exploiting their physical properties at each stage of the process. Magnetic separation removes ferrous metals first. Air or wet separation splits plastics from non-ferrous metals based on density. Electrostatic and vibrating table refining removes remaining contaminants. By sorting input materials, calibrating machine settings, and maintaining cutting tools, operators can achieve copper purity above 98 percent and recover aluminum and plastic as valuable secondary products. Whether you run a small scrap yard or a large industrial recycling plant, investing in the right cable recycling equipment is the key to turning waste cable into consistent, profitable raw materials.
