Environment

The streets of Vancouver are paved with ... recycled plastic

The streets of Vancouver are paved with ... recycled plastic
The warm mix truck laying the new asphalt mix at one of the trial locations in Vancouver
The warm mix truck laying the new asphalt mix at one of the trial locations in Vancouver
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A team of City of Vancouver officials has been working with Toronto's GreenMantra to develop an innovative new process that coverts 100 percent post-consumer recycled plastic waste into a wax that can be mixed into warm mix asphalt
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A team of City of Vancouver officials has been working with Toronto's GreenMantra to develop an innovative new process that coverts 100 percent post-consumer recycled plastic waste into a wax that can be mixed into warm mix asphalt
The warm mix truck laying the new asphalt mix at one of the trial locations in Vancouver
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The warm mix truck laying the new asphalt mix at one of the trial locations in Vancouver
The mix was a 19 mm Superpave, surface coarse warm-mix, with 20 percent reclaimed asphalt pavement and wax derived from blue box plastics
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The mix was a 19 mm Superpave, surface coarse warm-mix, with 20 percent reclaimed asphalt pavement and wax derived from blue box plastics
The City of Vancouver has developed a new warm mix paving process that uses a state-of-the-art wax material derived from 100 percent recycled plastics
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The City of Vancouver has developed a new warm mix paving process that uses a state-of-the-art wax material derived from 100 percent recycled plastics
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According to the Economist Intelligence Unit's latest Global Liveability Report, the beautiful city of Vancouver in Canada is a pretty decent place to live, ranking third in the world. Its environmental footprint is currently unsustainable, though, prompting officials to hatch an ambitious plan to have Vancouver crowned the greenest city in the world by 2020. Helping things along nicely is a new warm mix paving process that makes use of the kind of waste plastic placed in blue household recycling boxes by conscientious citizens, reducing greenhouse gases and improving air quality along the way.

A team of city officials, including Peter Bremner and Jeff Markovic from Kent Services, has been working with Toronto's GreenMantra to develop an innovative new process that coverts 100 percent post-consumer recycled plastic waste into a wax that can be mixed into warm mix asphalt.

"Warm mix asphalt is not all that new, but what is unique in our application is using a wax that was derived from recycled plastics," Karyn Magnusson from Vancouver's Engineering Services told Gizmag. "We have been trialing warm mix since 2008 with different kinds of additives designed to reduce the viscosity to make placement easier at lower temperatures. We have now paved three sections of Vancouver roads with this latest trial."

A team of City of Vancouver officials has been working with Toronto's GreenMantra to develop an innovative new process that coverts 100 percent post-consumer recycled plastic waste into a wax that can be mixed into warm mix asphalt
A team of City of Vancouver officials has been working with Toronto's GreenMantra to develop an innovative new process that coverts 100 percent post-consumer recycled plastic waste into a wax that can be mixed into warm mix asphalt

"The mix was a 19 mm Superpave, surface coarse warm-mix, with 20 percent reclaimed asphalt pavement and wax derived from blue box plastics," added Markovic. "The temperature was reduced from our typical 320°F [160ºC] to 250°F [121ºC], there's a significant reduction in VOC and CO readings at the plant, and visible reductions in fumes at the both the paver and the plant."

Other benefits revealed in the lab and road trials include 20 percent savings on gas used to heat the mix. Additionally, the City of Vancouver says that there is potential for additional grinding and re-using cycles of pavement, as the wax helps prevent aging of asphaltic oils. Mixing at lower temperatures allows for increased use of recycled asphalt content and lower use of virgin asphaltic oils.

"Paving season is now coming to a close, but next spring we will do some more trials and go back to look at the in-situ performance of the placed material," said Magnusson. "We have some work to do yet evaluating this trial, but if our testing continues to show the benefits we were anticipating then we would love to embrace this as the norm rather than as a special mix. Ideally we will also see somebody begin to produce this wax locally. The material we have used to date was created by a company in Toronto, it would be nice to see Vancouver plastic waste going into Vancouver roads."

Although the new development currently carries a three percent premium over typical hot mix, the developers believe this extra cost will disappear in the near future as a result of an ample supply of waste plastics.

Source: City of Vancouver

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6 comments
6 comments
Slowburn
It would seem to me that the plastic will be turned to dust and get everywhere eventually. and there are other ways to use plastic waste. I am apposed to using tar to make pavement because it can be catalytically cracked in to fuel so easily these days. http://www.gizmag.com/fluidized-bed-reactor-recycles-plastic-waste/17281/ http://www.gizmag.com/envion-plastic-waste-to-oil-generator/12902/ http://www.gizmag.com/plastic2oil-converts-plastic-to-fuel/19108/ http://www.gizmag.com/go/4534/
William Lee
Quite a lot more plastic waste than used tires..... Crumb rubber (from recycled tires) Asphaltic mixes still have a long way to go, and many projects were rammed through politically. This will be interesting to follow.
bigL
@william I work as the lab manager for the Australian private asphalt company TROPIC ASPHALTS. We have trialled and developed crumb rubber mixes with quite a lot of success throughout New South Wales' Hunter Region. Over the last 3 years we have laid in excess of 10,000 tonnes of crumb rubber mix and have seen good results, with greatly improved rut resistance, tensile strength, and surface texture. However this mix is not easy to work and is hard to lay onsite and requires considerably skilled foremans to execute. I have serious doubts of the above mentioned article claiming reduced consumption of gas by 20% whilst putting in 20% reclaimed asphalt pavement. We used processed RAP which is kept in dry storage sheds in selected mixes, and we see at least a 20% drop in temperature due to the moisture content. Although they are making "warm mix" at 120c, I still find this hard to swallow that they can improve efficiency of warm mix asphalt by incorporating RAP over the use of virgin aggregates. The use of RAP cuts costs but by no means does it reduces plant emissions. It will be interesting to see how and if the wax will adversely affect the binder quality, surely it will have some effect on viscosity. Time will tell....
Jan Angevine
The problem here is depending on plastic. We need to figure out how to stop producing petroleum products such as plastic. Our oil resources are finite. If we continue using them to produce plastic products we are assured of depleting our oil reserves leaving nothing for the production of petroleum products of a critical nature. I applaud the use of plastic that is currently here, but would suggest we not encourage further plastic production by suggesting that it now justified because it can be used to build highways. Even more important, if we use all the oil in our reserves, it is "game over" for the planet because of the CO2 emissions. Petroleum: lose-lose.
Leslie Satenstein
My curiosity is peeked. How is traction in -10C and below? How is traction if there was a spreading of salt to clear away post plowed streets?
Montreal only salts at intersections, but highways tend to get a lot more salt than do city streets.
I live in greater Montreal
AlbertCake
Awesome.I think all the countries must do this type of work so that the plastic recycling will become easy.