LA is testing asphalt made from plastic bottles

[kernals12]

https://patch.com/california/los-angeles/la-tests-streets-made-recycled-plastic-bottles

They say the binder is stronger and lasts longer than ordinary asphalt, resulting in a 50% reduction in lifecycle costs. And because it's made from recycled plastic bottles, it's supposed to be better for the environment. I wonder how this compares to rubberized asphalt.

[The Ghostbuster]

What happened to paving the streets with gold? I'm not sure if this new method of making asphalt is the "wave of the future"; I'd rather they stick to the old way of making asphalt, unless this new way is conclusively proven to work as advertised.

[kernals12]

What happened to paving the streets with gold? I'm not sure if this new method of making asphalt is the "wave of the future"; I'd rather they stick to the old way of making asphalt, unless this new way is conclusively proven to work as advertised.

The title says they're testing the new method, precisely to see if it works as advertised.

[roadfro]

This sounds promising. If it's successful, it might become part of the solution for the global plastic recycling problem.

[kernals12]

This sounds promising. If it's successful, it might become part of the solution for the global plastic recycling problem.

And it would greatly reduce the cost of road maintenance, freeing up DOT budgets for highway improvements and reducing the need for tolls or gas tax increases.

[kalvado]

This sounds promising. If it's successful, it might become part of the solution for the global plastic recycling problem.

And it would greatly reduce the cost of road maintenance, freeing up DOT budgets for highway improvements and reducing the need for tolls or gas tax increases.

Likely not. PET is pretty much recyclable as is. I have no idea if surplus amount of bottles exists, and if it does - is it due to issues with material processing or something else. I belive a lot of floor carpets were cola bottles in previous life, for example.
The only real benefit would be ability to accept bottles mixed 50-50 with crap like used diapers without additional processing.

[kernals12]

This sounds promising. If it's successful, it might become part of the solution for the global plastic recycling problem.

And it would greatly reduce the cost of road maintenance, freeing up DOT budgets for highway improvements and reducing the need for tolls or gas tax increases.

Likely not. PET is pretty much recyclable as is. I have no idea if surplus amount of bottles exists, and if it does - is it due to issues with material processing or something else. I belive a lot of floor carpets were cola bottles in previous life, for example.
The only real benefit would be ability to accept bottles mixed 50-50 with crap like used diapers without additional processing.

With enough heat applied, anything containing carbon could be made into asphalt.

[US71]

Likely not. PET is pretty much recyclable as is. I have no idea if surplus amount of bottles exists, and if it does - is it due to issues with material processing or something else. I belive a lot of floor carpets were cola bottles in previous life, for example.
The only real benefit would be ability to accept bottles mixed 50-50 with crap like used diapers without additional processing.

I read something a while back that seemed to indicate there are problems with recycling plastic.  Something about successive generations of plastic are poorer in quality. I don't know how that would affect using it as paving material, however.

[kalvado]

Likely not. PET is pretty much recyclable as is. I have no idea if surplus amount of bottles exists, and if it does - is it due to issues with material processing or something else. I belive a lot of floor carpets were cola bottles in previous life, for example.
The only real benefit would be ability to accept bottles mixed 50-50 with crap like used diapers without additional processing.

I read something a while back that seemed to indicate there are problems with recycling plastic.  Something about successive generations of plastic are poorer in quality. I don't know how that would affect using it as paving material, however.

There definitely is such a problem. That's why I mentioned carpeting as an application for less than prime material.
Overall, cost benefit, and supply steam come into the equation. How many lane miles can be made with available bottles supply? Should be a fairly easy thing to check

[kernals12]

Likely not. PET is pretty much recyclable as is. I have no idea if surplus amount of bottles exists, and if it does - is it due to issues with material processing or something else. I belive a lot of floor carpets were cola bottles in previous life, for example.
The only real benefit would be ability to accept bottles mixed 50-50 with crap like used diapers without additional processing.

I read something a while back that seemed to indicate there are problems with recycling plastic.  Something about successive generations of plastic are poorer in quality. I don't know how that would affect using it as paving material, however.

There definitely is such a problem. That's why I mentioned carpeting as an application for less than prime material.
Overall, cost benefit, and supply steam come into the equation. How many lane miles can be made with available bottles supply? Should be a fairly easy thing to check

If we manage to blow through the supply of used plastic bottles for paving roads, that would be a good thing from an environmental standpoint, and oil refineries could just sell virgin plastic directly to paving companies. 

[kalvado]

Likely not. PET is pretty much recyclable as is. I have no idea if surplus amount of bottles exists, and if it does - is it due to issues with material processing or something else. I belive a lot of floor carpets were cola bottles in previous life, for example.
The only real benefit would be ability to accept bottles mixed 50-50 with crap like used diapers without additional processing.

I read something a while back that seemed to indicate there are problems with recycling plastic.  Something about successive generations of plastic are poorer in quality. I don't know how that would affect using it as paving material, however.

There definitely is such a problem. That's why I mentioned carpeting as an application for less than prime material.
Overall, cost benefit, and supply steam come into the equation. How many lane miles can be made with available bottles supply? Should be a fairly easy thing to check

If we manage to blow through the supply of used plastic bottles for paving roads, that would be a good thing from an environmental standpoint, and oil refineries could just sell virgin plastic directly to paving companies.

Thing is, PET is used to replace sand in the mixture. I can think of PET being beneficial due to better pavement quality if it is dirt cheap (or sand cheap, pun intended); no way a virgin material would approach that pay grade.

[skluth]

Likely not. PET is pretty much recyclable as is. I have no idea if surplus amount of bottles exists, and if it does - is it due to issues with material processing or something else. I belive a lot of floor carpets were cola bottles in previous life, for example.
The only real benefit would be ability to accept bottles mixed 50-50 with crap like used diapers without additional processing.

I read something a while back that seemed to indicate there are problems with recycling plastic.  Something about successive generations of plastic are poorer in quality. I don't know how that would affect using it as paving material, however.

There definitely is such a problem. That's why I mentioned carpeting as an application for less than prime material.
Overall, cost benefit, and supply steam come into the equation. How many lane miles can be made with available bottles supply? Should be a fairly easy thing to check

If we manage to blow through the supply of used plastic bottles for paving roads, that would be a good thing from an environmental standpoint, and oil refineries could just sell virgin plastic directly to paving companies.

Thing is, PET is used to replace sand in the mixture. I can think of PET being beneficial due to better pavement quality if it is dirt cheap (or sand cheap, pun intended); no way a virgin material would approach that pay grade.

Sand is becoming a scarce resource. This BBC article talks about the amount of usable construction sand is running out. I'm not sure how that will affect prices here in the near future, but it is something to think about.

[triplemultiplex]

I can think of several problems with this concept.
The first being the way plastics behave when exposed to sunlight.  UV light breaks the bonds between the plastic molecules causing them to break into smaller and smaller pieces, especially when they are subjected to mechanical force.  So in my mind, a road sitting out in the sun all day every day and then having vehicles driving over it is likely to result in flecks of microplastic shedding from the road to be carried away by the wind and rain doing unknown things to the environment.  It seems unlikely the plastic component of the mix would be bonded strongly enough to the other materials of the asphalt mix to avoid this over the lifespan of the pavement.

That pretty much defeats the hope for a net positive environmental effect of mixing plastic in with asphalt.  The microplastic thing is the one of the main reasons to be concerned about all of our waste plastic in the first place.  This just seems to add a few steps to that process.  We have so much waste plastic because it's dirt cheap to make.  If plastic binder makes for better asphalt, what the industry will do is go straight to the chemical companies to get those plastics wholesale, rather than mess around with expensive collecting and sorting of waste plastic.  Sure, they'll throw a few Coke bottles in the mix for a little PR, but the bulk of it would be fresh material, straight from the refinery or whatever because that's going to be cheaper.

Now there is a future where we still have mountains of plastic waste to deal with and a bunch of our roads are flaking even more plastic into our environment.

[kernals12]

I can think of several problems with this concept.
The first being the way plastics behave when exposed to sunlight.  UV light breaks the bonds between the plastic molecules causing them to break into smaller and smaller pieces, especially when they are subjected to mechanical force.  So in my mind, a road sitting out in the sun all day every day and then having vehicles driving over it is likely to result in flecks of microplastic shedding from the road to be carried away by the wind and rain doing unknown things to the environment.  It seems unlikely the plastic component of the mix would be bonded strongly enough to the other materials of the asphalt mix to avoid this over the lifespan of the pavement.

That pretty much defeats the hope for a net positive environmental effect of mixing plastic in with asphalt.  The microplastic thing is the one of the main reasons to be concerned about all of our waste plastic in the first place.  This just seems to add a few steps to that process.  We have so much waste plastic because it's dirt cheap to make.  If plastic binder makes for better asphalt, what the industry will do is go straight to the chemical companies to get those plastics wholesale, rather than mess around with expensive collecting and sorting of waste plastic.  Sure, they'll throw a few Coke bottles in the mix for a little PR, but the bulk of it would be fresh material, straight from the refinery or whatever because that's going to be cheaper.

Now there is a future where we still have mountains of plastic waste to deal with and a bunch of our roads are flaking even more plastic into our environment.

Regular asphalt also gets damaged by UV radiation, and I'm sure it's also pretty bad for the environment.

[kalvado]

I can think of several problems with this concept.
The first being the way plastics behave when exposed to sunlight.  UV light breaks the bonds between the plastic molecules causing them to break into smaller and smaller pieces, especially when they are subjected to mechanical force.  So in my mind, a road sitting out in the sun all day every day and then having vehicles driving over it is likely to result in flecks of microplastic shedding from the road to be carried away by the wind and rain doing unknown things to the environment.  It seems unlikely the plastic component of the mix would be bonded strongly enough to the other materials of the asphalt mix to avoid this over the lifespan of the pavement.

That pretty much defeats the hope for a net positive environmental effect of mixing plastic in with asphalt.  The microplastic thing is the one of the main reasons to be concerned about all of our waste plastic in the first place.  This just seems to add a few steps to that process.  We have so much waste plastic because it's dirt cheap to make.  If plastic binder makes for better asphalt, what the industry will do is go straight to the chemical companies to get those plastics wholesale, rather than mess around with expensive collecting and sorting of waste plastic.  Sure, they'll throw a few Coke bottles in the mix for a little PR, but the bulk of it would be fresh material, straight from the refinery or whatever because that's going to be cheaper.

Now there is a future where we still have mountains of plastic waste to deal with and a bunch of our roads are flaking even more plastic into our environment.

Regular asphalt also gets damaged by UV radiation, and I'm sure it's also pretty bad for the environment.

Yes, but no. Dark tar used in asphalt should be a very efficient absorber, preventing UV from going beyond top few  0.001". That is pretty similar to black outdoor cables being plastic, typically polyethylene, impregnated with disperse carbon for UV absorption. 
I don't see a big problem with plastic degradation beyond that depth if tar is still used (and it should be) 

[kalvado]

Likely not. PET is pretty much recyclable as is. I have no idea if surplus amount of bottles exists, and if it does - is it due to issues with material processing or something else. I belive a lot of floor carpets were cola bottles in previous life, for example.
The only real benefit would be ability to accept bottles mixed 50-50 with crap like used diapers without additional processing.

I read something a while back that seemed to indicate there are problems with recycling plastic.  Something about successive generations of plastic are poorer in quality. I don't know how that would affect using it as paving material, however.

There definitely is such a problem. That's why I mentioned carpeting as an application for less than prime material.
Overall, cost benefit, and supply steam come into the equation. How many lane miles can be made with available bottles supply? Should be a fairly easy thing to check

If we manage to blow through the supply of used plastic bottles for paving roads, that would be a good thing from an environmental standpoint, and oil refineries could just sell virgin plastic directly to paving companies.

Thing is, PET is used to replace sand in the mixture. I can think of PET being beneficial due to better pavement quality if it is dirt cheap (or sand cheap, pun intended); no way a virgin material would approach that pay grade.

Sand is becoming a scarce resource. This BBC article talks about the amount of usable construction sand is running out. I'm not sure how that will affect prices here in the near future, but it is something to think about.

Give me a call when sand is cheaper than oil...

[US71]

Likely not. PET is pretty much recyclable as is. I have no idea if surplus amount of bottles exists, and if it does - is it due to issues with material processing or something else. I belive a lot of floor carpets were cola bottles in previous life, for example.
The only real benefit would be ability to accept bottles mixed 50-50 with crap like used diapers without additional processing.

I read something a while back that seemed to indicate there are problems with recycling plastic.  Something about successive generations of plastic are poorer in quality. I don't know how that would affect using it as paving material, however.

There definitely is such a problem. That's why I mentioned carpeting as an application for less than prime material.
Overall, cost benefit, and supply steam come into the equation. How many lane miles can be made with available bottles supply? Should be a fairly easy thing to check

If we manage to blow through the supply of used plastic bottles for paving roads, that would be a good thing from an environmental standpoint, and oil refineries could just sell virgin plastic directly to paving companies.

Thing is, PET is used to replace sand in the mixture. I can think of PET being beneficial due to better pavement quality if it is dirt cheap (or sand cheap, pun intended); no way a virgin material would approach that pay grade.

Sand is becoming a scarce resource. This BBC article talks about the amount of usable construction sand is running out. I'm not sure how that will affect prices here in the near future, but it is something to think about.

Give me a call when sand is cheaper than oil...

When h^ll freezes over?

The world is reportedly running out of sand.
https://www.cnet.com/news/the-world-is-running-out-of-sand-and-you-need-to-care/

[Bobby5280]

At some point society world-wide will have to make far more significant efforts at "mining" existing and even long-closed landfills for any reusable resources. The same goes for trash thrown directly into our oceans. The trick is how to sort such materials in a manner that is both safe and cost-effective. So far all I've seen is cursory efforts, like tapping into landfills to use the gases building inside of them for power.

Now there is a future where we still have mountains of plastic waste to deal with and a bunch of our roads are flaking even more plastic into our environment.

This isn't the first time I've heard of odd materials getting mixed in with asphalt. "Glasphalt" has been around since the 1970's, although it has limited uses. I'm all for anyone experimenting with different materials to find something that may be more durable and/or cost effective compared to standard asphalt. Any new alternative has to pass a number of tests, the least of which is safety. IIRC, glasphalt doesn't work so well on high speed highways since it increases skidding distance.

The growth of microplastics in our environment is a potentially very dangerous problem. The crap is infesting our oceans. The stuff gets eaten by fish, winds up in birds and creeps farther and farther up the food chain until it is getting into our food. There is no telling how much microplastics are already getting into the meat and produce we eat now. I wonder how well our water treatment systems work on filtering out the stuff. The long term effects of ingesting plastics cannot be good. For now, mankind seems all too happy turning the oceans and waterways into a giant toilet.

[1995hoo]

....

This isn't the first time I've heard of odd materials getting mixed in with asphalt. "Glasphalt" has been around since the 1970's, although it has limited uses. I'm all for anyone experimenting with different materials to find something that may be more durable and/or cost effective compared to standard asphalt. Any new alternative has to pass a number of tests, the least of which is safety. IIRC, glasphalt doesn't work so well on high speed highways since it increases skidding distance.

....

I know Fairfax County was using glasphalt for something recently, but I don't know all the details. Curbside pickup for glass recycling ended either last year or the year before and instead we drop it off at designated "purple bins." At some point they were crushing the glass and grinding it up for use in asphalt, though I'm pretty sure it wasn't used in any VDOT projects. Part of the reason for all that had to do with problems selling the recycling to China due to broken glass being hard to separate from paper and plastic. I'm not sure they're still using glasphalt–I read something about them having found a customer that will recycle it into new glass products.

[skluth]

The growth of microplastics in our environment is a potentially very dangerous problem. The crap is infesting our oceans. The stuff gets eaten by fish, winds up in birds and creeps farther and farther up the food chain until it is getting into our food. There is no telling how much microplastics are already getting into the meat and produce we eat now. I wonder how well our water treatment systems work on filtering out the stuff.

Not good. Remember microbeads being advertised in shampoos? They were also in cosmetics and toothpaste. Congress banned them in 2015 because they were getting past treatment plants and into the Great Lakes and other waterways.

[kernals12]

Does bitumen not create environmental problems?

[Bobby5280]

Does bitumen not create environmental problems?

I would think bitumen poses its own hazards. But that poses another question. Would bitumen be used as a hot liquid binder in asphalt made with recycled plastic? I'm inclined to think it would still be a necessary ingredient in this new kind of asphalt just like with regular asphalt.

Remember microbeads being advertised in shampoos? They were also in cosmetics and toothpaste. Congress banned them in 2015 because they were getting past treatment plants and into the Great Lakes and other waterways.

The whole situation is disgusting. We already have enough failures in our food and water safety systems that all kinds of cattle run-off shit and piss (among many other pollutants) are getting into the food and water we eat and drink. We're doing things barely good enough to get by, just good enough to be barely above third world standards. But let's throw a bunch of hormones and other stuff into our meat. That way we can have kids hitting puberty before age 10!

This microplastics stuff is on a whole other dimension for how pervasive it is in our waterways and the life forms that live in those waters. I don't know if it's just unchecked advertising from Big Pharma or if it's an indication of growing medical problems. But it seems like more people than ever have all sorts of odd allergy issues, gastro-intestinal issues (like IBS, Chron's, etc), ADHD and on and on. I can't help but wonder if that is a side effect to the unnatural foods we're eating, stuff we're drinking and even the air we're breathing in some locations. I'm sure there are other factors involved too (like parents doing lots of drugs and alcohol while pregnant). But the way our food and water is being altered is really pretty scary.

[kernals12]

Does bitumen not create environmental problems?

I would think bitumen poses its own hazards. But that poses another question. Would bitumen be used as a hot liquid binder in asphalt made with recycled plastic? I'm inclined to think it would still be a necessary ingredient in this new kind of asphalt just like with regular asphalt.

Remember microbeads being advertised in shampoos? They were also in cosmetics and toothpaste. Congress banned them in 2015 because they were getting past treatment plants and into the Great Lakes and other waterways.

The whole situation is disgusting. We already have enough failures in our food and water safety systems that all kinds of cattle run-off shit and piss (among many other pollutants) are getting into the food and water we eat and drink. We're doing things barely good enough to get by, just good enough to be barely above third world standards. But let's throw a bunch of hormones and other stuff into our meat. That way we can have kids hitting puberty before age 10!

This microplastics stuff is on a whole other dimension for how pervasive it is in our waterways and the life forms that live in those waters. I don't know if it's just unchecked advertising from Big Pharma or if it's an indication of growing medical problems. But it seems like more people than ever have all sorts of odd allergy issues, gastro-intestinal issues (like IBS, Chron's, etc), ADHD and on and on. I can't help but wonder if that is a side effect to the unnatural foods we're eating, stuff we're drinking and even the air we're breathing in some locations. I'm sure there are other factors involved too (like parents doing lots of drugs and alcohol while pregnant). But the way our food and water is being altered is really pretty scary.

By all objective measures, waterways in the United States and all developed countries have never been cleaner. My Mom grew up on Lake Erie in the 1970s, she knows how bad things used to be.

[kalvado]

Does bitumen not create environmental problems?

I would think bitumen poses its own hazards. But that poses another question. Would bitumen be used as a hot liquid binder in asphalt made with recycled plastic? I'm inclined to think it would still be a necessary ingredient in this new kind of asphalt just like with regular asphalt.

Remember microbeads being advertised in shampoos? They were also in cosmetics and toothpaste. Congress banned them in 2015 because they were getting past treatment plants and into the Great Lakes and other waterways.

The whole situation is disgusting. We already have enough failures in our food and water safety systems that all kinds of cattle run-off shit and piss (among many other pollutants) are getting into the food and water we eat and drink. We're doing things barely good enough to get by, just good enough to be barely above third world standards. But let's throw a bunch of hormones and other stuff into our meat. That way we can have kids hitting puberty before age 10!

This microplastics stuff is on a whole other dimension for how pervasive it is in our waterways and the life forms that live in those waters. I don't know if it's just unchecked advertising from Big Pharma or if it's an indication of growing medical problems. But it seems like more people than ever have all sorts of odd allergy issues, gastro-intestinal issues (like IBS, Chron's, etc), ADHD and on and on. I can't help but wonder if that is a side effect to the unnatural foods we're eating, stuff we're drinking and even the air we're breathing in some locations. I'm sure there are other factors involved too (like parents doing lots of drugs and alcohol while pregnant). But the way our food and water is being altered is really pretty scary.

Frankly speaking, after looking at things - I am not totally convinced microplastics are THAT worse than sand.
And a clear result of non-natural foods can be seen in life expectancy. it increased from ~37 years in 18th century when the food was all natural to ~80 years today. Keep in mind, natural selection almost stopped working for humans, so those who, health-wise, should have died as kids (including your's truly) are living much longer and keep farting about poor health care.

[triplemultiplex]

That would be nice if indeed digestive systems handled microplastic the same as it does inert geological material like sand.  (Life forms have been incidentally swallowing sand and other minerals for as long as there has been eating, so nature knows how to poop that out no problem.). One of the many uncontrolled experiments our species is running on a planetary scale these days.


Worth noting that asphalt itself was once a waste product of oil refining.  One that was repurposed into something useful when applied to roofs or mixed with sand and gravel for road surfaces.  It's a know respiratory health hazard when volatilized, yet it's ubiquitous in our built environment.