Metal waste is valuable – if it's properly separated. The following overview shows typical waste streams and how modern recycling plants, especially BLUELINE, get the most out of each material stream.
Metal recycling is not just a matter of sustainability – it is a strategic pillar for economic resilience, environmental protection and industrial progress.
As regulatory frameworks increasingly demand a circular economy and lower emissions, companies that proactively invest in recycling technologies gain a clear competitive advantage and stay ahead of future requirements.
Sustainability is therefore no longer an option, but a fundamental prerequisite for future viability. Recycling plays a crucial role because it significantly reduces energy consumption, conserves finite resources, and ensures a more stable, domestic supply of raw materials that make an important contribution to modern everyday life.
Many metals, with sufficient degree of purity, can be recycled multiple times with only a small loss in quality. In comparison, primary extraction from ores is highly resource-intensive and associated with significant CO₂ emissions and environmental pollution (mining).
Considering both environmental and economic benefits, it is helpful to understand the most common metal waste streams encountered today.
Common metal waste streams
Shear Scrap
A diverse mix of various materials, including unwanted components such as soil, stones, wood and plastics, but also valuable metals such as iron (Fe), aluminum (Al), stainless steel (VA) and copper (Cu).
Shredder Scrap
A coarse, metal-rich mixture of materials resulting from the shredding of bulky industrial waste. These material streams consist of a wide variety of materials, depending on whether pre-sorting (for ferrous, non-ferrous metals, waste, or dust) has already taken place.
Non-Ferrous Metals
Non-ferrous metals are metals without iron content, such as aluminum, copper, or brass. They are non-magnetic, corrosion-resistant, and have a high recycling value.
Aluminium
A lightweight, corrosion-resistant, and versatile material, it plays an important role as one of the most recycled materials. Recycled aluminum uses only a fraction of the energy compared to its original production.
E-Waste
Electronic waste (PCs, smartphones, household appliances, etc.) is one of the fastest-growing waste streams. It is increasing by approximately 4% annually and is expected to reach 75 million tons by 2030. It contains precious metals such as gold, silver, and platinum, as well as rare earths and non-ferrous metals.
Ash / Slag
Ash is the solid residue left behind after waste incineration in modern waste incineration plants. Ash and slag consist primarily of mineral components, but often also contain recyclable metals, including precious metals.
Foundry Residue
Foundry residues are wastes from metal casting processes that often contain recyclable metals and reusable mineral components. These include spent molding sand, slag, dust, and metal scrap from melting, casting, and other process steps.
Cable Scrap
Discarded or no longer used electrical cables and wires, usually made of insulated copper or aluminum conductors.
Efficient Metal Recycling: Recognize Problems, Implement Solutions
▶ BLUELINE offers all established processing steps of dry mechanical recycling:
▶ Dosing
▶ Screening
▶ Magnetic Separation
▶ Eddy Current Separation
▶ Density & Shape Sorting
▶ Sensor-based Sorting
A feed hopper (dosing system) transfers material streams evenly and continuously onto a screening module. During screening, the material is classified into the appropriate grain size for further processing. Depending on the material composition and particle size, various processes can then be used to recover valuable components from these waste streams.
Magnetic Separation
Magnetic particles such as ferrous metals (e.g., nails, screws) are removed by magnetic attraction. This is particularly useful for the recovery of ferrous metals or for pre-sorting the material for downstream processes such as eddy current separation.
Eddy Current Separation
A rotating pole wheel induces eddy currents in all conductive particles. The resulting magnetic field acts opposite to the magnetic field of the pole wheel, repelling the particles in question.
Systems for Magnetic Separation
MAGNET DRUM
A magnetic separator consisting of two differently configurable magnetic drums. This allows both strong and weak magnetic particles to be removed from the material stream in a single step.
Overbelt Magnet
Our "Conveyor M-Series" belt conveyor removes ferrous particles from mixed material streams easily and effectively using an overbelt magnet.
FEED VIBRO ▶ TOP RECOMMENDATION
Our robust feed hopper with a built-in magnetic drum for removing magnetic particles is a practical and powerful solution for refining the material flow during dosing.
Systems for Eddy Current Separation
EDDY ACTIVE ▶ TOP RECOMMENDATION
This eddy current sorter has one of the most powerful eccentric magnet systems on the market and ensures particularly intensive separation of almost all conductive particles.
EDDY ONE
The static magnet system is particularly suitable for homogeneous fractions with small particle sizes (e.g. cable scrap).
EDDY CENTRIC
Ferrous and non-ferrous separators combined, this module offers an efficient and compact solution for obtaining 3 different fractions in one processing step.
Density and Sensor-based Sorting for Stainless Steel, Mixed NF-Metals and ECS Drops
As already mentioned, eddy current separators are ideal for removing non-ferrous, conductive particles from non-conductive materials such as wood or plastic.
Although slightly magnetic particles such as stainless steel are repelled by the eddy current separator due to their electrical conductivity, they are also attracted by their slightly magnetic properties. Therefore, they are often sorted as ECS drops. Unfavorable shape or size can also lead to particles not being ejected properly.
Furthermore, eddy current separators are generally not used to extract non-ferrous metals from mixed metal concentrates. Complementary technologies such as sensor-based sorting and density sorting are available for this purpose.
Density & Shape Sorting
In density sorting, particles are separated based on their density. The particle shape and individual particle weight also influence the separation behavior. This process is particularly effective for separating light and heavy metals from non-ferrous metal mixtures such as zorba, zurik, and non-ferrous metal slag.
Sensor-based Sorting
In processing technology, sensor-based sorting systems enable the targeted separation of particles by detecting and evaluating material-, color-, and shape-specific properties using a wide variety of sensor technologies. Common sensor technologies include induction strips, color cameras, near-infrared (NIR) cameras, and even X-ray transmission (XRT).
Systems for Density & Shape Sorting
SORT FLUID ▶ TOP RECOMMENDATION
Our dry sink-float system – an innovative solution for metal separation, completely without liquid.
By coordinating airflow, gravity, and a special bed material, the particles are precisely separated. The result: highly efficient separation of light and heavy metals with purities of up to >99%.
SORT FINES
Dosing accuracy and precise air control – this makes our SORT FINES air jig the ideal solution for the precise sorting of fine-grained material up to a max. grain size of 25 mm – efficient, dry and with the highest purity.
All relevant parameters (dosage, air zones, sieve insert inclination, etc.) can be set fully automatically at the touch of a button, managed centrally via BLUECtrl and called up at any time when required.
Systems for Sensor-based Sorting
SENSOR IDENTIFY ▶ TOP RECOMMENDATION
This sensor sorter detects all conductive particles using an induction strip and separates them specifically using compressed air pulses.
Particularly suitable for mixed waste streams of conductive and non-conductive materials or for the re-sorting of eddy current fractions (ECS drops), for example to sort out stainless steel or sheathed cable residues.
SENSOR UNCOVER
Detects what others miss. The X-ray sorting system with X-ray transmission (XRT) makes the sensor insensitive to surface contamination and even allows the detection of inclusions within the particle.
Why BLUELINE? 5 Reasons to choose us
First-class modular recycling solutions for efficient and flexible sorting – perfectly tailored to your individual requirements.
BLUELINE is leading in technological developtment, and offers advanced solutions for efficient recycling processes.
BLUELINE is tailored to the needs of your business. We understand that every company is unique, and so are our solutions.
BLUELINE offers an extensive product range, which can be used for almost all types of material streams.
BLUELINE modules require little maintenance, which reduces operating costs and downtimes to an absolute minimum.
BLUELINE uses high quality materials to provide exceptional longevity and reliability of the machines.