rnOver the years, with the continuous expansion of industries, the amount of wastes produced has increased significantly. This trend has adversely affected the availability of damping sites and landfills, the cost of their usage has increased significantly.
If we consider the roofing industry alone, it produces tonnes of asphalt shingles, cedar shakes, and wood waste every year. Disposing of all the waste has not only become expensive but is also hurting our environment badly.
A single asphalt shingle takes a few manufacturing hours but takes almost 300 years to decompose completely. Considering the amount of asphalt shingle waste produced every year and the time it takes to decompose, the only sustainable and eco-friendly way out of the problem is recycling.
The article below talks about the process of recycling asphalt shingles and the benefits it offers to both the economy and the environment.
Shingle Composition
rnThe four main components of asphalt shingles are
Mineral filler
Asphalt cement
Mineral granules
Felt backing or fiberglass
An asphalt shingle is fiberglass or felt mat that is saturated with the granules of small rock known as asphalt cement. Fiberglass asphalt shingles contain 19 to 20 percent of asphalt cement, while organic asphalt shingles contain 30 to 36 percent of asphalt cement.
Mineral granules are actually sand-sized ceramic-coated natural rocks that make 20 to 38 percent of the shingles. Lastly, various stabilizers are added to the structure, with composition weightage ranging from 8 to 40 percent. Some of the commonly used stabilizers are limestone, silica, or dolomite.
The felt mat serves as the back straps that hold the material together. Generally, two types of felt mat are used in asphalt shingle, namely;
Fiberglass feltrnOrganic felt mat using paper
Recycling Process
The asphalt shingles recycling process involves the production of Hot-mix asphalt (HMA) by grinding the shingles into small pieces and repurposing them to fill cracks and potholes on the road.
However, before the grinding process, shingles are sorted, and extraneous materials are removed. The grinding process varies everywhere and is carried according to local or state laws and regulations. If the shingles are being recycled for a private project, then it is done according to the contractors’ demands.
The size of recycled shingle pieces (ranging between 0.25 to 2-inches) depends on their post-recycling use. If the recycled material is intended to be used as base stabilization, the size of the ground shingles will be kept large. On the other hand, the size is kept between 0.25 to 0.5 inches if the material is intended to serve as an asphalt surface course.
However, recycled shingles are not usually used alone; they are mixed with soft shingles to remove the hardness of the asphalt shingles. Generally, the HMA can have five percent of the recycled material by weight.
Use Of Recycled Asphalt Shingles
Recycled asphalt shingles and asphalt shingle scrap can be used in a variety of products. Some of them are;
Parking lots rnNew roofing rnRoad coversrnPothole patch rnBridges rnRampsrnGround cover rnAsphalt pavementrnUtility cuts rnAggregate base and cut base rnFuel oil rnDust control on rural roads rnHot mix asphaltrnWarm mix asphaltrnCold patch
Benefits Of Recycling Asphalt Shingles
Recycling asphalt shingles offer benefits to both the
roofing company and the customer. Some of them are
Environmental benefits
Recycling old shingles reduces the amount of new fuel needed and decreases the dependence on foreign oil.rnRecycling helps reduce the amount of construction waste since the material is not sent to landfills and other damping sites.rnRecycling of the mineral particles that are produced during the process of asphalt pavement prevents natural resources. rnRecycling helps reduce the environmental hazards caused by overfilled or leaking landfills.
Economic Benefits
Recycling asphalt is an easy way for taxpayers to save money. rnContractors save ample money by cutting down on material, transportation, and energy costs. rnAsphalt can be recycled over and over again, ensuring its value. rnIn the long run, recycling will surely reduce the material cost significantly because the industry will use minimum new material.
Other Benefits
Some other benefits of using recycled asphalt shingles include
The improved quality of pavement because there is a stronger cracking resistance and rutting owing to the addition of mineral granule fillers and organic fiber used in shingles. rnRecycling provides an alternative to aggregate, decreasing the need for mined aggregates.rnImproved HMA mixes rnIt reduces the amount of gravel lost. rnThe recycled material reduces the amount of dust produced in the process.rnRAS can also be used as the temporary surface for the driveways, roads, and parking lot.
Conclusion
Recycling asphalt shingles can help the roofing industry to align best to the world’s sustainability goals. Recycling asphalt shingles benefits the industry, contractors, economy, and the environment along with increasing the quality of materials and projects it is used in.