Earthquake Rebuilding with Recycled Tire Logs
Replace lumber with recycled rubber Tire Logs. Photo from Re-Tread Products
Don't grind old tires; slice 'em and roll 'em up into rubber logs to use like lumber. From footwear to handbags and earthship homes, recycled tires have found various forms of an afterlife, but that doesn't come close to dealing with the vast numbers of waste tires generated each year. Most "recycling" of tires involves rubber grinding which is a source of pollution and a huge energy guzzler. But designed to be indestructible, tires have a useful after life. So how can millions of discarded Bridgestones and Goodyears help fortify the rebuilding of Haiti, and now earthquake-ravaged Chile? Tire Logs. Re-Tread Products produces a low-tech version of recycling tires that has several applications. With the advantage of the "bend don't break" flexibility of the material, Tire Logs have proven effective in various civil engineering projects, including earthquake-resistant building, sea walls, highway noise barriers, and sandbag replacements for erosion control. They also eliminate toxins from chemically treated wood that leaches into the water system and without the ineffecient energy that grinding rubber into new materials produces.
Diagram of ReTread's Tire Log process
With an R&D; grant from New York's States' Environmental Services Unit, the Tire Log was used as a replacement for chemically treated timbers in the construction of retaining walls. They're resistant to decay and useful in areas prone to earthquakes, wave action, explosions and vehicle impacts.
Unlike many other waste materials, tires can't be compacted and are tough to grind down into marketable material. Most often, old tires are shredded for landfill not upcycled into new products. Here's the breakdown on what happens:
• 130 million (44.7%) are used as Tire Derived Fuel (TDF)
• 56 million (19.4%) are recycled or used in civil engineering projects
• 18 million (7.8%) are converted into ground rubber and recycled into products
• 12 million (4.3%) are converted into ground rubber for rubber-modified asphalt
• 9 million (3.1%) are exported
• 6.5 million (2.0 %) are recycled into cut/stamped/punched products
• 3 million (1.7%) are used in agricultural and miscellaneous uses
Another 16.5 million scrap tires are retreaded. After retreading has been done, 290 million scrap tires are generated. About 27 million scrap tires (9.3%) are estimated to be disposed of in landfills. Reuse of scrap tires would be a start to remove them from waste and put to good use but there's been pressure against it.
Old and Tired. Photo by Jesse Garnder via Flickr
The environmental hazards of stockpiled tires has been dealt with primarily by grinding up the rubber. Many are seeking lots of innovative solutions to the disposal problem. Grinding old rubber copes with the large quantities of waste tires, but the end products aren't that great either. In 2006, the US generated 300 million new waste tires, 76% (228 million) of these tires were ground up in one form or another and then utilized for three major end uses - fuel, crumb rubber and buried as fill.
Tire Logs began as a safety utility pole made from tire tread material. The logs are produced by a commercially available sidewall removing machine--sliced not diced. Then they're formed into various shapes. The rectangular stackable Tire Log provides a durable building material that can be applied in various construction applications, especially those requiring environmental and physical stresses but without deterioration.
Re-Tread is looking to transform those 300 million discarded tires annually and go into full scale production.
More on recycling tires:
Are Shredded Tires Polluting Our Playgrounds?
Recycled Tire Logs Say to Pressure Treated Lumber, "Anything You Can Do..."
Weasel Word Watch: Tire & Trash Burners Lobby For "Renewable" Status