Construction and demolition waste recycling
Turn concrete, masonry and demolition waste into usable aggregate products
Why choose Metso for C&D waste recycling
Separate rebar and metal
Process concrete, brick and masonry
Produce clean, sized material
Reduce unnecessary material handling
Construction and demolition waste can contain many different materials. Concrete, bricks, blocks and other masonry can be suitable for crushing and screening, while steel and other unwanted materials need to be separated from the feed.
The condition of the incoming material matters. Demolition waste can be uneven and may contain metal, soil, wood, plastic and other contaminants. Sorting the material before processing helps produce a cleaner and more consistent aggregate product.
How is construction and demolition waste recycled?
The process depends on the feed material and the products you want to make.
- Sort the feed
Remove large unwanted materials and separate different material streams where possible. - Crush the material
A jaw or impact crusher reduces concrete and other suitable demolition material to a smaller size. - Remove metal
Magnetic separation can remove steel such as rebar from the crushed material. - Screen the material
Screening separates the crushed material into the required product sizes. - Recirculate oversize when needed
Oversize material can be returned to the crusher for further processing.
Additional processing for concrete reuse
When the goal is to reuse recovered aggregate in fresh concrete mixes, pre-crushed concrete can be processed further with Metso HRC™ high-pressure grinding rolls technology. HRC helps separate the aggregate from the cementitious material without further crushing the aggregate.
The final process setup depends on the feed, contamination, required capacity and the aggregate products you want to produce.
Where recycled aggregates are used
Processed concrete, brick and masonry can be used in applications such as road construction, infrastructure and earthworks.
Typical applications can include:
- Road base and sub-base
- Fill and backfill
- Working platforms
- Other approved construction and infrastructure uses
The final use depends on the quality of the recycled aggregate, local regulations and project requirements. Always check that the material meets the requirements for its intended use.
C&D waste can vary in size and composition, and concrete may contain rebar and other unwanted material. The right crushing and screening setup depends on the feed, required products, production target and site conditions.
Mobile crushing and screening
For operations that move between demolition sites or process material close to the source.
Portable crushing and screening
For recycling operations that relocate but need a more plant-like production setup.
Stationary and modular plants
For continuous recycling operations at a fixed location.
Metso recycling equipment — quick reference
Key equipment options
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Pan feeder and grizzly scalper with two vibrating units — handles uneven feed without blockages and separates fines before the crusher.
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Opens jaw crusher cavity automatically when unbreakables enter — protects machine, no production stop.
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Removes ferrous metal (rebar, wire) from the product stream.
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Separates light materials (plastic, wood, insulation) from crushed aggregate.
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Dust enclosures keep the site cleaner and make it easier to get crushing permits in residential and built-up areas.
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Water sprays control dust at the crusher and conveyors.
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Purpose-built for noise-restricted and urban sites — reduces crusher noise by up to 60% with integrated dust suppression.
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Washes out clay, silt and fines from recycled concrete and C&D waste — keeping output quality and value high.
Frequently asked questions
Construction and demolition waste recycling turns concrete, brick, masonry and other suitable demolition materials into aggregate products that can be used again. The process typically includes sorting, crushing, screening and removing steel and other unwanted materials. The final products can be used in applications such as road construction, foundations and fill where local requirements allow.
For concrete and demolition waste, an impact crusher is often the first choice for primary crushing, while a jaw crusher can also be used depending on the feed and process. Metso offers Nordberg® NP Series™ horizontal shaft impact (HSI) crushers and Nordberg® C Series™ jaw crushers for these applications. Metso HRC™ roll crushers can be used at a later processing stage for pre-crushed concrete. These crusher technologies are available in mobile tracked equipment and stationary or modular plant configurations.
Impact crushers are well suited to crushing concrete and other demolition material. Jaw crushers can also be used, depending on the hardness and size of the feed and the required end product. Metso offers Nordberg® NP Series™ HSI impact crushers and Nordberg® C Series™ jaw crushers in different mobile, portable and stationary crushing solutions.
C&D waste can contain rebar and other difficult material, so good material flow and easy cleaning are important. A pan feeder and scalping feeder combination can help handle uneven demolition feed and maintain a steady material flow. Wide conveyors, generous clearances and good cleaning access also help material move smoothly through the machine and reduce blockages.
For jaw crushers, Metso's Active Setting Control (ASC) can help handle uncrushable objects. When an uncrushable object enters the crusher, ASC automatically opens the crusher setting to let it pass and then returns to the original setting for continued crushing. For applications where reverse crushing may be considered for clearing blockages, ASC uses a different approach: it opens the crusher setting to release the uncrushable object.
C&D waste can contain metal, wood, plastic, insulation, soil and other unwanted material. Sorting before crushing helps control the feed. During processing, magnetic separators can remove ferrous metal, while windsifters can separate light materials such as plastic and insulation. Washing equipment can also be used when clay, silt and other fine material need to be removed.
Mobile tracked crushers and screens suit operations that move frequently between demolition or construction sites. Portable wheel-mounted equipment can suit operations that relocate periodically, such as projects that move approximately every one to two years. Stationary or modular plants can suit continuous production at a fixed location, such as a recycling center. Metso offers Lokotrack® and Nordtrack™ mobile equipment, Nordwheeler™ portable plants and Nordplant™ stationary and modular solutions.
Crushed concrete can be further processed to recover aggregate for reuse in concrete production. The concrete is first pre-crushed with an impact crusher. Metso HRC™ technology can then process the crushed concrete further, helping separate the aggregate from the cementitious material without further crushing the aggregate. The recovered aggregate can then be used in fresh concrete mixes. The required process depends on the feed material and the quality requirements for the recovered aggregate. HRC™ technology is available in stationary Nordplant™ configurations and as the portable Nordwheeler™ NW8HRC.
C&D waste places different demands on crusher wear parts than quarry rock. The right wear material depends on the crusher type, feed material, abrasiveness and impact conditions. Manganese steel needs repeated hard impacts to work-harden. With softer recycling feed, it may not harden sufficiently, which can lead to faster wear.
For impact crushers processing concrete, Metso offers application-specific blow bars, including Metso MMC Martensitic blow bars for Nordberg® NP Series™ crushers and martensitic blow bars with optional ceramic inserts for Nordtrack™ impact crushers. Slotted blow bars are also available for recycling applications to help reduce fines and wear and improve capacity and material flow.
The right equipment depends on the feed material, required capacity, end products and site conditions. Metso can support equipment and process selection with free-of-charge feed material testing in our rock laboratory and Bruno process simulation. These services can help evaluate the material and compare different crushing and screening setups to find a suitable solution.
