At Green Roads Recycling® we believe that reducing, reusing and recycling are the best ways to a sustainable future, as well as the best use of the taxpayer’s dollar when it comes to revamping roads.
Reusing the Rock & Oil:
- Preserves all the energy and raw materials (natural resources) that would be used to make the new road.
- Prevents waste and pollution from ripping up and hauling away the old road.
Reducing the Energy Required to Repave the Road:
- Saves fuel going to and from the asphalt plant with the new material.
- Saves fuel to pick up and move the old asphalt
- Saves the energy and chemicals used to make all new materials.
- Lowers greenhouse gas emissions by 27 tonnes per kilometre when compared to conventional paving methods. Twenty-seven tonnes.
Recycling the Roads:
- Leaves the aggregate intact for future generations. (Aggregate doesn’t degrade and can be reused many times)
- Preserves all the energy and raw materials (natural resources) that went into making the asphalt in the first place, which means less mining and less drilling for oil and gas.
- Burns less fuel in trucks and machinery, and produces less pollution.
Calculations show that it requires roughly 500,000 BTU’s to produce a tonne of new asphalt. To recycle a tonne of asphalt in place requires roughly 200,000 BTU’s. Since HIPAR uses approximately 60 per cent less energy it produces 60 per cent less greenhouse gases when producing a tonne of asphalt mix. All of today’s recycling trains are equipped with emission control systems. These systems are tested annually by independent testing companies and are required to meet stringent air quality standards.
All Recycled Paving Methods Are Not Equal
The argument in favor of recycling asphalt isn’t a hard one to make. If we recycle beer cans, why not roads? But unlike beer cans, the recycling method is as important as choosing to recycle in the first place. In other words, not all recycled paving methods are equal. What makes this method special is that it is done in place. In other words, we don’t have to pick up the existing road, haul it away, recycle it somewhere else and then bring it back.
RECYCLING ASPHALT WITH "RAP"
RAP or Recycled Asphalt Pavement is an asphalt recycling method that cold mills the asphalt rather than warm mills it. Cold milling requires pulverizing the aggregate within it, trucking the asphalt away from the road site, and then trucking it back. Clearly, the extra cost (to the environment and to the taxpayer) incurred by the trucking of the asphalt is an issue. However, there’s a more serious problem related to the pulverizing of the aggregate.
Keep in mind that aggregate does not degrade. It can be used in roads over and over again. Pulverizing the aggregate, however, means that we have lost some of the value. Once you pulverize it, you’ve degraded the aggregate distribution which was engineered specifically for strength and longevity. The engineered mix and the aggregate residual value are worth millions when you consider how many times a given road may need re-paving. Consider the lifecycle cost of this.
HIPAR, on the other hand, uses warm milling at the road site, which recycles the aggregate without pulverizing it. The value of the aggregate and the engineered mix is preserved for future rehabilitations.
In the future do we, as North Americans, want to be remembered as a society that squandered away this enormous investment (aggregate) without realizing its true value?
In addition, Only 20 per cent of RAP is currently used in bottom-lift hot-mix applications. In other words, when you use RAP in the mix design it needs and overlay.
Using Used Tires & Asbestos in Roads
Current trends in the road rehabilitation focus on initial cost but if we focus on the full life-cycle cost, we might make better decisions (“better” meaning decisions that our children and children’s children will thank us for, for environmental and economic reasons).
For example, some regions in Eastern Canada have started disposing of asbestos by putting it into roads. Initially this might save some money and seem like a good decision. But when the road falls apart, the removal and disposal costs, not including the health hazard risk, will be over 100 times the initial construction cost. At HIPAR, we think this is neither sustainable nor economical.
Some areas are starting to dispose of used tires by putting them into roads. Again, this might seem like an innovative technique and a good decision. But when the percentage of used rubber tires in the road is greater than 3 to 5 per cent, the road cannot be recycled. It must be thrown away. Planned obsolescence in road building is not the way to a sustainable future.
Plus, these toxic materials, be they asbestos or used rubber, may leech into the ground and water tables over time.
At HIPAR, we suggest that using our roads as linear landfills does a disservice to future generations and does not take into account the full life-cycle costs.
Most recycling industries are subsidized, which costs taxpayers millions of dollars every year. Hot-in-place recycling (HIPAR) is not. It’s a market-based solution that just happens to also be really great choice for the environment.
Choosing HIPAR means:
- Significant cost savings
- Minimal traffic and retail disruptions
- Reduced life cycle costs
- Increased asphalt longevity
That’s not all:
- Existing roads are deteriorating quicker than they are being rehabilitated.
- As taxpayers, it’s in our best interest to preserve the oil, sand and rock that we have already extracted and processed because they represent an enormous investment. We can’t let them deteriorate. There should be no more throw away.
- The price of oil rose by more than 100 per cent in the last few years. Indications are that it is going to continue to rise exponentially. Every increase in the cost of oil increases the value of the oil in the existing roads…as long as those roads are recycled. Conventional paving techniques do not fully utilize the value of the existing oil and aggregate. The enormous investment put into the roads by previous generations is lost.
- Just by tendering more contracts, government can help develop a world-leading, home grown industry.
- HIPAR is the most effective method for certain roads in the right conditions.
- Uncoated aggregate is remixed and recoated
- Ruts and holes filled
- Shoves and bumps levelled
- Crown and drainage re-established
- Asphalt flexibility restored by chemically rejuvenating the aged asphalt
- Aggregate gradation and asphalt content may be modified
- Highway safety enhanced through improved ride and skid resistance
- Lower engineering costs
- Lower traffic control cost and traffic interruption