Production and Applications of Crumb Rubber

Tens of millions of tires are discarded across the Middle East every year. Disposal of  waste tires is a challenging task because tires have a long life and are non-biodegradable. The traditional method of waste tires management have been stockpiling or illegally dumping or landfilling, all of which are short-term solution. 

Crumb rubber is a term usually applied to recycled rubber from automotive and truck scrap tires. There are two major technologies for producing crumb rubber – ambient mechanical grinding and cryogenic grinding. Of the two processes, cryogenic process is more expensive but it produces smoother and smaller crumbs.

Ambient Mechanical Grinding

In ambient mechanical grinding process, the breaking up of a scrap tire happens at or above normal room temperature. Ambient grinding is a multi-step technology and uses whole or pre-treated car or truck tires in the form of shred or chips, or sidewalls or treads. The rubbers, metals and textiles are sequentially separated out. Tires are passed through a shredder, which breaks the tires into chips.

The chips are fed into a granulator that breaks them into small pieces while removing steel and fiber in the process. Any remaining steel is removed magnetically and fiber through a combination of shaking screens and wind sifters. Finer rubber particles can be obtained through further grinding in secondary granulators and high-speed rotary mills.  

Ambient grinding is the production process used by the majority of crumb producers. The machines most commonly used for fine grinding in ambient plants are:

  • Secondary granulators
  • High speed rotary mills
  • Extruders or screw presses
  • Cracker mills

Cryogenic Grinding

Cryogenic grinding refers to the grinding of scrap tires at temperatures near minus 80oC using liquid nitrogen or commercial refrigerants. Cryogenic processing generally uses pre-treated car or truck tires as feedstock, most often in the form of chips or ambiently produced granulate.

Processing takes place at very low temperature using liquid nitrogen or commercial refrigerants to embrittle the rubber. It can be a four-phase system which includes initial size reduction, cooling, separation, and milling. The material enters a freezing chamber where liquid nitrogen is used to cool it from –80 to –120 °C, below the point where rubber ceases to behave as a flexible material and can be easily crushed and broken.

Because of its brittle state, fibres and metal are easily separated out in a hammer mill. The granulate then passes through a series of magnetic screens and sifting stations to remove the last vestiges of impurities. This process requires less energy than others and produces rubber crumb of much finer quality.  

Applications of Crumb Rubber

Both ambient and cryogenic processing can be repeated to produce finer particles. Increasingly, the two with their attendant technologies, are combined into one continuous system in order to benefit from the advantages and characteristics of each and to reduce overall costs.

The ambient system is generally used for the initial size reduction phases. The cryogenic system is used to further reduce the material in size and then to remove the metals and textiles. The outputs from either or both systems can be used directly or as feedstock for further processing.

Rubber crumb is sold as feedstock for chemical devulcanization or pyrolysis processes, added to asphalt for highway paving and pavement sealers, or used for the production of a large number of recycled rubber-containing products. Some of the major applications of crumb rubber are as follows:

Sport Surfaces

  • Kindergarten Playgrounds and Recreation Areas
  • School Sports Areas
  • Athletic Tracks
  • Tennis and Basketball Courts

Automotive Industry

  • Bumpers
  • Splash Guards and Fenders
  • Floor Mats for Cars and Trucks
  • Floor Liners for Trucks and Vans


  • Hospital, Industrial, and Bathroom Flooring
  • Floor Tile
  • Foundation Waterproofing
  • Dam, Silo, and Roof Liners

Geotechnical/Asphalt Applications

  • Rubberized Asphalt for Roads and Driveways
  • Drainage Pipes
  • Soil Conditioner
  • Porous Irrigation Pipes
  • Road Building and Repair

Adhesives and Sealants:

  • Adhesives and Sealing Compounds
  • Textured and Non-Slip Paints
  • Roof Coating and Waterproofing

Shock Absorption and Safety Products

  • Shock Absorbing Pads for Rails and Machinery
  • Sound Barriers for Highways
  • Abrasion Lining in Mining Equipment

Rubber and Plastic Products

  • Pipe Insulation and Lining
  • Garbage Cans
  • Shoe Soles and Heels
  • Wire and Cable Insulation


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About Salman Zafar

Salman Zafar is a renowned consultant, advisor, entrepreneur and writer with expertise in waste management, waste-to-energy, renewable energy, environment protection and sustainable development. He is the Founder of EcoMENA, in addition to being the CEO of consultancy firm BioEnergy Consult. Salman has successfully accomplished a wide range of projects in the areas of biomass energy, biogas, waste-to-energy and waste management. He has participated in numerous conferences and workshops as chairman, session chair, keynote speaker and panelist. Salman is a professional writer and is proactively engaged in creating mass awareness on renewable energy, waste management and environmental sustainability. He can be reached at or
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12 Responses to Production and Applications of Crumb Rubber

  1. Fatima Al-Banna says:

    This is interesting. Recycling tires can be an out-come of other products. We have parkes here in UAE that is used recycled tires for walking paths. Its brillilant yet healthy and very safe for the kids and prevent small plants growing other than the normal paths 🙂

  2. Subhash A Niyogi says:

    Good one studied and written Salman

  3. Farooq Khan says:

    Recycling is an important element of waste treatment.
    Waste Disposal in M.E is not primarily considered in aappropriate manner, thus
    the disposal of waste contributes to environment hazards.
    Recycling is one of proper waste dosposal method and it needs encouragement with
    government subsidy.

  4. STEVEN LEUWE says:

    Waste rubber recycling is very appropriate in the mordan world because it takes care of the environment also complements raw materiels and not only that but creates employment.

  5. vishal jain says:

    can anyone pls mail its project report on I`ll be very thankful.

  6. Udit says:

    this is a very informative blog.Can anyone please send a project report on crumb rubber to . I’ll really be very thankful.

  7. David Thomas says:

    I would be most greatfull for any information on tyre recycling please reply to

  8. Wasim Rashid says:

    I would be very great-full for any information of a project on tyre recycling in Middle East, specially in Saudi Arabia please send me by

  9. Teddy says:

    Very interesting. Rather than burning used tyres to melt asphalt/range in the barrel and polute the environment, it creates a business opportunity and reduce unemployment specially in the developing countries.

  10. Manoj Sharma says:

    I would be grateful if someone send me the process & project report of rubber mat for car, truck and floor mat. We are already in recycling of rubber industries.

  11. Swapnil says:

    Can anybody have project report , ppt or procees reports.

    pls suggest me on

  12. Chirag says:

    Please give me project full details

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