Rubber Crumb

Tyre recycling lines look like mineral processing plants and behave nothing like them.

Elasticity and static

Rubber particles rebound at transfer points and spread beyond the intended path, and dry conveying charges them strongly.

• Enclosed transfers with generous clearances so bouncing material stays inside.
• Grounded, conductive components and controlled humidity where practical.
• Belt and vibratory conveying in preference to long pneumatic runs.

Screening and blinding

Textile fibre liberated during granulation wraps around screen wires and blinds the deck quickly.

Screens with ball decks, brush cleaning or ultrasonic systems keep the aperture open, and fibre separation upstream reduces the load.

Steel removal

Residual bead and belt wire damages granulators and contaminates the product.

Magnetic separation at several points along the line is normal, with the final check immediately before packing.

Fire risk

Rubber dust and fibre are combustible, and stored crumb piles can self-heat.

Dust collection with explosion protection and controlled pile sizes are the usual measures.

What to establish before buying equipment

• Target particle size range and the fibre content at that cut.
• Steel content and the separation stages planned.
• Bulk density, which is low and affects silo and bag sizing.
• Dust collection and explosion protection for the granulation area.

Rubber crumb is elastic, light and charges strongly, which makes it behave unlike any mineral granule.

It bounces rather than settles, it clings to surfaces through static, and residual steel and textile fibre from tyre recycling cause problems far downstream.

• Expect poor settling: a silo holds less than its volume suggests.
• Earth and bond; static makes crumb cling and makes dust collection harder.
• Verify steel and fibre removal upstream rather than discovering it in the process.

Elasticity and static set the design.

Crumb bounces at transfer points and escapes from open chutes, and it packs in tight clearances rather than flowing through them. Screw conveyors need generous clearances; pneumatic transfer needs conductive components.

• Enclosed transfers with generous geometry.
• Conductive, earthed components throughout.
• Magnetic and density separation upstream, verified rather than assumed.

Rubber dust is combustible and a rubber fire is hard to extinguish and heavily polluting.

• Dust collection with explosion protection where fines accumulate.
• Fire planning that accounts for a deep-seated, smoky fire.
• Housekeeping; fine rubber dust accumulates quickly and burns readily.