Incineration slag is a common industrial solid waste, but its proper treatment and recycling can bring great value. RUIJIE, a professional leader in slag separation equipment, helps enterprises turn waste into treasure with high-quality machines and scientific solutions.
What Is Incineration Slag?
Incineration slag is a solid residue formed after high-temperature incineration of garbage, industrial waste, or other materials. It is a non-metallic mixture floating on the surface of molten materials during incineration, which solidifies when cooled.
Unlike other industrial slags, incineration slag is more complex, usually mixed with scrap iron, aluminum, copper, glass, ceramics, and gravel—making it both a waste and a recyclable resource.
Key Characteristics of Incineration Slag
Incineration slag has unique characteristics that determine its sorting difficulty and treatment method, which are different from ordinary metallurgical slag.
• High moisture content: Easy to agglomerate, affecting sorting accuracy and equipment operation.
• Uneven particle size: Contains large lumps and fine powder, requiring graded treatment before sorting.
• Complex composition: Mixed with ferrous metals, non-ferrous metals, and various impurities, increasing sorting complexity.
• Partial weak magnetism: Some slag contains weak magnetic substances, which interfere with magnetic separation.
• Easy wrapping: Valuable metals are often wrapped in slag, requiring crushing to expose them.
Common Sources of Incineration Slag
Incineration slag is mainly produced in high-temperature incineration processes, with three main sources in industry.
• Municipal solid waste incineration: The most common source, generated after garbage incineration in waste treatment plants.
• Industrial waste incineration: Produced by incineration of waste from factories, such as chemical waste, textile waste, and metal processing waste.
• Hazardous waste incineration: Generated from the incineration of hazardous waste, which requires more professional sorting and treatment.
Uses of Incineration Slag
After proper sorting and treatment, incineration slag can be fully reused, realizing resource recycling and reducing environmental pollution.
1. Construction materials: Processed into aggregates for roads, concrete, and building foundations, replacing natural stones.
2. Brick making: Used to produce environmental protection bricks, permeable bricks, and aerated blocks, saving clay resources.
3. Cement production: As a mixed material for cement, improving cement strength and reducing production costs.
4. Metal recovery: Extracting ferrous and non-ferrous metals (iron, aluminum, copper) through sorting, creating additional economic value.
5. Backfill engineering: Used for backfilling foundation pits, mine collapse areas, and depressions, realizing harmless treatment.
Which Characteristics of Incineration Slag Affect Sorting?
The sorting effect of incineration slag depends largely on its own characteristics, which are also the main pain points faced by the industry.
– Moisture content: High humidity causes material agglomeration, leading to low sorting accuracy and equipment blockage—most peers ignore this, resulting in frequent failures.
– Particle size: Too large or too small particles cause missed sorting and jamming; peers often use single-screening equipment, failing to achieve graded sorting.
– Density difference: Similar density between non-ferrous metals and impurities makes separation difficult; many peers only use single eddy current separators, with low purity.
– Magnetic interference: Weak magnetic substances interfere with magnetic separation, causing mis-sorting of ferrous metals.
– Metal wrapping: Wrapped metals cannot be separated by magnetic or eddy current force, requiring effective crushing—peers’ crushers have weak force and incomplete crushing.
How to Choose the Right Incineration Slag Sorting Solution?
Choosing a sorting solution must be based on the characteristics of incineration slag; a one-size-fits-all solution cannot achieve efficient sorting.
• For high moisture: Add drying and dewatering links (dewatering screen + spiral sand washer) to ensure materials are loose.
• For uneven particle size: Adopt “crushing + graded screening” (hammer crusher + drum screen) to separate different particle sizes for targeted sorting.
• For similar density: Combine gravity sorting and eddy current sorting (jig + eddy current separator) to improve separation purity.
• For magnetic interference: Add pre-magnetic separation (magnetic separator) to remove magnetic impurities first.
• For metal wrapping: Use high-efficiency crushing equipment to break the wrapping structure, ensuring metals are exposed.
How Does RUIJIE Equipment Sort Incineration Slag?
RUIJIE has developed a complete incineration slag sorting line, combining multiple professional equipment to solve industry pain points.
Firstly, materials are evenly conveyed by a feeder to the rotary trommel screen for size classification.
Oversized materials are transported under the electromagnetic over-band separator, where large iron blocks and magnetic materials are adsorbed and separated for direct recycling.
Smaller materials are sent to the permanent magnetic drum to separate magnetic and non-magnetic materials.
Those magnetic materials fall into the iron crusher, while non-magnetic materials enter the sand crusher. After being crushed to the required size, they flow into the magnetic separator to extract ferrous materials, and then pass through the jig machine for gravity separation with water.
Fine iron powder discharged from the jig machine is finally recovered by the suspended permanent magnetic separator and shaking table.
Non-metallic materials are sent to the eddy current separator to separate large aluminum and small aluminum for recovery.
Light sand from crushed sand and gravel flows with water to the spiral sand washer for cleaning. Floating materials are removed by the floating trommel screen, and the sand is dewatered by the dewatering screen before entering the finished product bin.
The whole production line forms a closed-circuit recycling process. Equipped with secondary re-crushing and secondary jigging, it maximizes the recovery of all recyclable materials without any waste.
It features a recovery rate up to 98%, pollution-free, zero discharge, high efficiency, low investment and high output.
RUIJIE’s Vision
RUIJIE has always adhered to the purpose of “Turning Industrial Waste into Valuable Resources, Creating Green and Efficient Future”.
We focus on solving the points of incineration slag sorting for customers, providing high-quality, stable, and cost-effective equipment and integrated solutions, helping enterprises reduce costs, increase efficiency, and achieve green recycling.
Choosing RUIJIE is choosing a reliable partner for incineration slag sorting, and choosing a sustainable development path for your enterprise.
