Formwork, square timber and demolition timber often contain nails, bolts, concrete blocks and sand. Magnetic separation is only effective after the metal is released, so the iron removal position must match the crushing stage.
Material characteristics
- Pallets, furniture boards, construction lumber and garden branches vary widely in size, wood species, moisture content and metal attachments.
- Nails, corners, sand, plastics and coatings can affect wear, magnetic separation and the use of the finished product.
- Pelletizing, fuel, board raw materials and volume reduction external sales correspond to different wood chip particle size, fine powder and moisture content requirements.
Key processing challenges
- The unreleased nails are still embedded in the long wooden strips and are difficult to be sucked out by magnetic separation.
- Concrete and gravel can cause high wear and mix into the finished product.
- Rectangular wood mixed with chipboard, uneven feeding and loading.
Equipment-selection criteria
- Determine the feed inlet, conveying and anti-bridging design based on the largest wooden parts, stacking method and forklift or gripper loading.
- Check the allowable boundaries of cutters, low-speed drives and metal parts containing nailed wood, and set appropriate magnetic separation positions.
- Secondary crushing, screening, iron removal, dust removal and storage solutions are deduced from the end use.
Typical process flow
Large pieces of concrete and extra-long metal are manually pre-sorted, and the wood is shredded in the first level and then magnetically separated and screened. When fine wood chips are needed, iron removal is set up before and after secondary crushing to protect subsequent equipment and reduce metal residues.
Information required before project evaluation
Complete information helps us define equipment limits, test plans and the full line accurately:
- Waste wood types, sources and proportions of each type
- Maximum size, thickness, moisture content and stacking method
- Nails, sand, plastic and coating conditions
- Target chip sizes, fines and end uses
- Hourly throughput, shifts and loading methods
- Magnetic separation, dust removal, fire protection and storage conditions