Waste cable looks like a messy, tangled problem, but inside a modern recycling plant it moves through a carefully ordered sequence of mechanical steps that turns scrap into saleable copper and clean plastic. The process is entirely dry and physical: sorting, size reduction, granulation, and density-based separation. It needs no water, no chemicals and no burning. Understanding that flow is the difference between choosing a machine that just "works" and running a plant that actually protects the value of every kilogram of copper it processes. This guide explains the process flow inside a cable recycling plant, step by step, and shows the equipment that makes each stage possible.
Why the process matters as much as the machine
Two loads of cable can look alike from a distance yet behave very differently inside equipment. Automotive harness wire may carry metal clips and terminals, communication cable may contain very fine conductors, appliance cable may have flexible insulation that does not cut cleanly, and large power cable may still be better handled by stripping before granulation. Because of this, a good recycling line is built around the feedstock rather than the discharge outlet. Every stage exists to solve one practical problem: free the copper conductor from its insulation completely, and then separate the two cleanly, so as little metal as possible is lost into the waste stream.
Stage 1: Receiving, inspection and sorting
The process starts before a single blade turns. Incoming cable is inspected and sorted to remove anything that could jam the machine or contaminate the output — large steel connectors, plugs, rubber blocks, stones, wet sludge and unrelated e-waste. Sorting also groups the material by type. Thick, valuable copper cable is often worth stripping separately, while thin and complex mixed wire is sent to the granulator, where manual scraping would be far too slow and inconsistent.
A few quick checks guide the sort: is the conductor copper or aluminium, since the two have different grades? Is the feed dry, because damp insulation carries fines and clogs screens? Is the size range too wide for one setting? Answering these four questions up front keeps the rest of the line stable and the recovery rate high.
Stage 2: Pre-cutting and shredding
Some scrap goes straight into a granulator, but tangled bales, long harnesses and compressed wire bundles usually need a preparation stage first. A scrap cable stripper peels the insulation from heavier cable so the metal can be captured directly as bare copper, and a pre-chopper or shredder reduces long lengths to a predictable size before they reach the granulator. In a complete plant this stage also protects downstream equipment: it smooths out sudden motor loads, stops long wire wrapping around shafts, and gives the granulator a consistent bite.
Shredders use rotating shafts to rip material down to a rough but manageable size. San Lan supplies single-shaft and multi-shaft shredders sized for different feeds, including a dual single-shaft model designed specially as a cable pre-chopper, so the line can be matched to the exact tonnage arriving on site.
Stage 3: Granulation — cutting cable into copper rice and plastic fragments
The granulator is the heart of the plant. Its job is to cut the prepared cable down until the copper conductor and the plastic insulation come apart cleanly. This is called liberation, and it is the target of the whole stage — not simply the smallest possible particle. If the pieces stay too large, copper remains locked inside the insulation; if they go too fine, the amount of copper dust and plastic fines rises, which lowers recovery and makes dust control harder.
A well-set granulator produces discrete granules the industry calls "copper rice" alongside plastic fragments. It does not melt the cable and uses no chemicals — it simply prepares the material so that the separator can do its work. San Lan's cable granulators, such as the compact WCD-200C and the higher-capacity WCD-1200S, match this granulation step to the throughput the plant expects, with models designed for volumes from a few hundred kilograms up to a tonne or more per hour.
Stage 4: Magnetic separation for steel content
Where the incoming cable includes armoured or steel-wrapped types, a magnetic separator pulls the ferrous content out early. Steel is magnetic while copper is not, so the magnet can lift the armour away cleanly without touching or damaging the copper underneath. Removing this steel at this point keeps it out of the copper stream and protects the purity of the final output.
Stage 5: Air-gravity separation splits copper from plastic
Once the cable is granulated, the mixed granules move to the separator, which works entirely on one physical property: density. Copper is far heavier than the plastic insulation around it, so when the mixture passes over a vibrating screen under a controlled airflow, the two materials travel different paths. The heavier copper granules fall into the copper outlet, the lighter plastic pieces carry further and discharge separately, and borderline material exits as a mixed fraction to be returned for another pass.
In real production the operator balances feed rate, screen vibration, air volume and particle size together rather than adjusting one setting blindly. If copper appears in the plastic outlet, the air may be too strong or the feed too fast. If plastic appears in the copper outlet, the air may be too weak or the material not fully liberated. Well-run granulation lines are reported to recover around 99% of the copper physically present in the cable, but that figure belongs to a line that keeps separation sharp, not one that runs on guesswork.
Stage 6: Optional electrostatic separation for high purity
Air-gravity separation is the standard workhorse stage, but some materials benefit from a polishing pass. Fine wire, flexible insulation and mixed cable grades can leave a little copper clinging to the plastic or plastic clinging to the copper. In that case an electrostatic separator is added after the main table. It takes advantage of the different charging behaviour of conductors and non-conductors in a high-voltage field, pulling the last traces of metal out of the plastic stream. Plants producing high-value clean copper or very clean plastic add this stage to lift purity further.
Stage 7: Dust collection and environmental control
Dry cable recycling always creates some dust — from the insulation, from copper fines and from surface contamination. A pulse dust collector and a sealed air-duct system pull this dust through the line, keeping the working area clean, protecting operators, and capturing fine copper that would otherwise be lost into waste. Good dust control is part of good recovery: it keeps the air breathable around the plant and stops fine metal from floating away uncollected.
Stage 8: Quality checking and output handling
The last stage does not judge the process by how shiny the copper outlet looks. Instead, samples are taken from the copper fraction, the plastic fraction and the mixed return at the same time. A bright copper stream is not enough if most of the copper is quietly leaving through the plastic outlet. Operators look for copper carry-over in the plastic, plastic contamination in the copper, copper still wrapped in insulation, moisture, and the volume of the mixed stream. Each of these tells them which setting to adjust. Recovered copper granules are bagged for sale to be remelted into new wire, while the separated plastic is itself recycled rather than landfilled, so both materials close the loop.
The complete plant as one integrated line
Put together, a practical dry cable recycling line usually follows this layout: feed sorting area, an optional shredder or pre-cutter for long and tangled cable, a feeding conveyor, a granulator, an air-conveying section, a vibrating screen or air-gravity separator, a dust collector, separate copper and plastic outlets, an optional electrostatic separator, and finally bagging and quality-control sampling. Arranged this way, the equipment is not a collection of unrelated machines but a single connected system that moves the material from tangled waste to two clean, saleable streams.
This is how a full cable recycling plant such as San Lan's WCW series is designed — pre-shredding, granulation and dry separation combined into one line capable of handling tonnes of cable per hour. The company has manufactured this type of cable recycling equipment since 2007, supplying granulators, strippers, shredders and complete plants to buyers in more than twenty countries, with custom design and installation support for each project.
Key factors that protect your recovery rate
Most recovery problems are not caused by one dramatic failure but by small mismatches — uneven feed, dull blades, damp insulation, excessive fines, poor air settings or skipped sampling. A few adjustments matter most. Keep the feed rate steady instead of dumping batches in, because overfeeding pushes mixed particles across the screen before they have time to stratify. Keep the cutters sharp and the clearances correct, since dull blades smear insulation into long strips instead of clean fragments. Control particle size so it is small enough for liberation but not so fine that copper dust increases. Adjust air and vibration together as the feed changes, and always return the mixed fraction for another pass rather than contaminating the final copper or plastic stream.
Summary
The process flow inside a cable recycling plant is a dry, mechanical sequence that turns scrap into recoverable value. Scrap is inspected and sorted, then pre-cut or shredded, granulated into copper rice and plastic fragments, freed of any magnetic steel, and separated by density through airflow and vibration. A dust collector keeps the line clean, an optional electrostatic stage polishes purity, and careful quality checking tells the operator where recovery is being lost. Every stage protects the copper that would otherwise disappear into the waste stream. For recyclers planning a new operation, matching each stage with the right equipment — and integrating them into one line — is what turns an ordinary pile of cable into a plant that pays for itself.
