Recycling

As a major producer and user of construction materials, Colas endeavors to recover waste and used materials from construction and other industries and recycle them in road construction. The Group’s recycling activity falls into four categories:

• The use of scrap from other industries or “secondary raw materials” in road construction, with: Colsoft (a noise-reducing asphalt mix that contains fine rubber powder from used tires), Scintiflex (an eye-pleasing surfacing product that contains mirror-glass waste), the Fractal wall (a noise barrier that contains waste wood) and Compogom or Draingom (a technique developed for base courses using shredded tires)

• The recovery of waste from the road industry and the construction industry through recycling platforms: treatment of dirt debris with the Ecosol process, the reuse of mastic asphalt from sidewalks, concrete demolition rubble, in-place recycling of asphalt concrete and the incorporation of RAP into new asphalt mixes

• Substituting products with equivalent quality and cost: construction rubble, fines from thermal power stations often used to manufacture asphalt mix, slag from the steel industry in Lorraine, eastern France, etc

• The use of sub-normal materials with lower-level technical characteristics for reasons of public interest, including bottom ash from household waste incineration plants and molding sand. These materials are employed only if the customer specifies them or if their use is subsidized. Colas handles more than 40% of the bottom ash produced in the Greater Lyon area, for example. The Group keeps a watchful eye on this type of reuse to make sure that there is no impact on the structures’ quality or durability

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In all, the reuse and recycling performed by Colas represents:

• more than 10 million metric tons of materials in France and elsewhere in the world,
• or 12% of the Group’s total aggregate production, equivalent to the total production of 32 average-sized quarries.
  

Looking solely at the picture for asphalt mix, Group production includes an average 9% of RAP (reclaimed asphalt pavement), which represents:

• savings of roughly 3.5 million tons of raw materials (rock and bitumen) or the equivalent production of 35 average-sized asphalt plants,
• plus savings of around 175,000 metric tons of bitumen, the equivalent of an average-sized refinery.

In-place recycling is a field that is booming. Colas currently treats around 6 million m2 of pavement per year throughout the world, but particularly in Morocco, southwest France and North America. Colas offers a wide range of suitable techniques, notably the “Nova” product line.