Research group finds way to turn plastic waste products into jet fuel(phys.org)
phys.org
Research group finds way to turn plastic waste products into jet fuel
https://phys.org/news/2019-06-group-plastic-products-jet-fuel.html
37 comments
Nice achievement, but I just don't see the environmental angle. The article implies that this might help solve the ocean plastic problem, but the plastic in the ocean isn't the plastic we carefully collected - it's the plastic that "got away". We won't be turning that into jet fuel any time soon.
And of course, taking the larger view, plastic is still made from fossil oil. Making it profitable to burn it is not going to help CO2 levels. The CO2 problem is larger than the ocean plastic problem, and even if we could turn ocean plastic into jet fuel - it's probably a bad trade.
And of course, taking the larger view, plastic is still made from fossil oil. Making it profitable to burn it is not going to help CO2 levels. The CO2 problem is larger than the ocean plastic problem, and even if we could turn ocean plastic into jet fuel - it's probably a bad trade.
If there was a use for collected plastic, a lot less of it would "get away", currently most of collected plastic ends up in landfills anyway. Burning jet fuel obtained from plastic would not decrease CO2 level, but it would not increase it either, as there is lots of other jet fuel to burn.
If it were profitable to turn plastic into jet fuel, that would imply that plastic-derived jet fuel is cheaper. If the price of jet fuel goes down, more gets burned.
By that logic you can argue that banning plastic bags will decrease the use of oil, making it cheaper for those who want to burn it. Or that buying tesla makes oil cheaper and in some other place more of it gets burned. In all of these cases the effect is tiny.
It's a question of supply and demand. If your final goal is to burn less oil, then you want to 1) reduce the supply and 2) reduce the demand. Buying Tesla reduces demand: good. Turning plastic to oil increases supply: bad.
Your plastic bag example is interesting because I think it's accurate - having plastic compete with combustion as a use for crude oil is good from an emissions standpoint, because when the wells run dry, less of it will have been burned.
(Plastic bags are indeed a bit of a silly example because there's so little plastic in them - we ban them because they cause disproportionate environmental harm)
Your plastic bag example is interesting because I think it's accurate - having plastic compete with combustion as a use for crude oil is good from an emissions standpoint, because when the wells run dry, less of it will have been burned.
(Plastic bags are indeed a bit of a silly example because there's so little plastic in them - we ban them because they cause disproportionate environmental harm)
It would increase it if it leads to more fuel supply.
I think you are right. Going fossil -> plastic -> fossil doesn't sound super efficient. And single use plastic should be just banned.
This tech could be useful in a majority renewable economy. If we assume that there is a certain amount of single use plastic that fulfills useful funtions that are hard to replicate, then turning that into jet fuel is kind of useful, as jet fuel needs high energy density and is one of the things we probably are not going to electrify any time soon. The CO2 is not new emission, but is just displaced, plus any CO2 cost of the process, which is somewhat reduced if the rest of the power and transportation has already transitioned across to other power sources.
This is not a way of solving anything per-se, but is a potential technology in an economy where we have already banned burning oil that hasn't been used a few times, and then only in things that absolutely require it.
This is not a way of solving anything per-se, but is a potential technology in an economy where we have already banned burning oil that hasn't been used a few times, and then only in things that absolutely require it.
>The CO2 is not new emission, but is just displaced
How do you figure? It wasn't going to be burned before. Now it is.
The sustainable way to make jet fuel would be some kind of renewable-powered carbon sequestration - for example, the process described in the paper, but fed with biomass. Burning old plastic is just fossil fuel with extra steps - looked at another way, it's a way to make fossil fuel cheaper by making it earn money as plastic before it gets burned. It's not a win.
How do you figure? It wasn't going to be burned before. Now it is.
The sustainable way to make jet fuel would be some kind of renewable-powered carbon sequestration - for example, the process described in the paper, but fed with biomass. Burning old plastic is just fossil fuel with extra steps - looked at another way, it's a way to make fossil fuel cheaper by making it earn money as plastic before it gets burned. It's not a win.
>It wasn't going to be burned before. Now it is.
Unless we are burning it in a second load of planes built specially for the occaision, it will replace the jet fuel from virgin crude that was going to be used for those trips.
I agree that it would be better to feed it with recent biomass, though I would note that this process would also presumably work with plastic made from recent, rather than fossil biomass and we may find that making some single use plastic, (sometimes having a single use wrapper is important), from biomass and then jet-fueling it at the end, might not be a bad way to go, at least until we have developed really good power storage in other ways.
Unless we are burning it in a second load of planes built specially for the occaision, it will replace the jet fuel from virgin crude that was going to be used for those trips.
I agree that it would be better to feed it with recent biomass, though I would note that this process would also presumably work with plastic made from recent, rather than fossil biomass and we may find that making some single use plastic, (sometimes having a single use wrapper is important), from biomass and then jet-fueling it at the end, might not be a bad way to go, at least until we have developed really good power storage in other ways.
We probably can't turn ocean plastic into jet fuel, but if there's an economic interest in converting plastic to jet fuel we could learn the future amount of plastic that ends up in the ocean.
Recycling has failed because it needs strict adherence and even then the products from plastic recycling are rarely the nice kind of plastic you need to build consumer goods.
Recycling has failed because it needs strict adherence and even then the products from plastic recycling are rarely the nice kind of plastic you need to build consumer goods.
> isn't the plastic we carefully collected - it's the plastic that "got away".
From what I understand, it is the plastic we carefully collected, but didn't properly dispose of. Instead, it was sold to someone else who wasn't so careful or of dubious morals, and they didn't let it get away, they just plain threw it away. If that's truly the case, then hopefully we could cut out the inept or unscrupulous middlemen, and use it for something instead of disposing it.
From what I understand, it is the plastic we carefully collected, but didn't properly dispose of. Instead, it was sold to someone else who wasn't so careful or of dubious morals, and they didn't let it get away, they just plain threw it away. If that's truly the case, then hopefully we could cut out the inept or unscrupulous middlemen, and use it for something instead of disposing it.
Unless plastic gets away because there isnt a high enough price per kg to incentivise collection (sadly, by homeless and poor probably).
This could raise price dramatically for post consumer plastic.
This could raise price dramatically for post consumer plastic.
As a few people have pointed out, this feels a lot like an attempt at solving one environmental problem (proliferation of waste plastic) by exacerbating another environmental problem (burning more fossil fuels). But if it took off, it could potentially serve as something of an intermediary step between our fossil fuel economy and a renewables-based economy. After all, the switch from horses to automobiles took 50 years. (https://thetyee.ca/News/2013/03/06/Horse-Dung-Big-Shift/, https://www.mnn.com/green-tech/transportation/blogs/horses-h...) A similar shift to renewables could easily take as long or longer.
Exactly. From a carbon/global warming sense, this is actually worse.
Plastic is carbon that never went into the atmosphere. It's actually nicely stored away, wildlife effects aside. Once you burn it, it's like you were burning oil.
Plastic is carbon that never went into the atmosphere. It's actually nicely stored away, wildlife effects aside. Once you burn it, it's like you were burning oil.
Oil in the ground is also carbon that wasn't in the air.
If the amount of jetfuel consumed stays the same, the amount of CO2 going into the air stays about the same. Could slightly increase or decrease depending on the processes' efficiency compared to the marginal oil producers' efficiency.
If the amount of jetfuel consumed stays the same, the amount of CO2 going into the air stays about the same. Could slightly increase or decrease depending on the processes' efficiency compared to the marginal oil producers' efficiency.
Fuel made from recycled plastic will displace fuel made directly from petroleum. So it will make the first problem (disposing of used plastic) better while not making the second problem (carbon dioxide emissions) any worse.
Obviously this isn't useful if we manage to eliminate fossil fuels altogether, but we're a long way from that.
Obviously this isn't useful if we manage to eliminate fossil fuels altogether, but we're a long way from that.
It's only worse if people fly more as a result. Otherwise you are just replacing one energy source for another.
This alone doesn't mean more energy is being used.
This alone doesn't mean more energy is being used.
Adidas is producing millions of its shoes using ocean plastic: https://mymodernmet.com/adidas-parley-sustainable-fashion (and these shoes can be then turned into jet fuel).
I think at this point they've moved to just "intercepting" plastic before it makes its way into the ocean. From the parley website:
"In remote areas, we establish systems to intercept plastic waste before it ends up in landfills, gets burned, buried or tossed into rivers or oceans."
So still might be more interesting than the recycled water bottles everyone else is sourcing but maybe disingenuous for them to be using the "ocean plastic" language still.
"In remote areas, we establish systems to intercept plastic waste before it ends up in landfills, gets burned, buried or tossed into rivers or oceans."
So still might be more interesting than the recycled water bottles everyone else is sourcing but maybe disingenuous for them to be using the "ocean plastic" language still.
Love this idea but as another user has pointed out, it's the plastic that 'gets away' that we should be concerned about. Similarly, microplastics in the ocean are - and will continue to be - a massive problem. A great concept, but sadly only one cog in a very confusing machine.
The only question that matter is net yield of energy per energy expended vs cost.
Net energy yield matters, yes, but assuming a negative net energy (seems reasonable), we could still get the negative from renewable sources.
Maybe I read too much science fiction, but I see a day in the future when we deploy autonomous technology at scale to deal with the greenhouse gasses and waste plastics of the fossil fuel era - little (or big) robots/factories that just take in energy from the Sun and use it to convert old waste into a manageable/useful form.
Realistic? I dunno. But it's certainly more hopeful than the Malthusian dystopia of shaming people for staying warm and eating and traveling.
Maybe I read too much science fiction, but I see a day in the future when we deploy autonomous technology at scale to deal with the greenhouse gasses and waste plastics of the fossil fuel era - little (or big) robots/factories that just take in energy from the Sun and use it to convert old waste into a manageable/useful form.
Realistic? I dunno. But it's certainly more hopeful than the Malthusian dystopia of shaming people for staying warm and eating and traveling.
No it's not. Converting renewable energy into liquid fuels is valuable in itself.
There are already different processes for this, including a rather nice one developed by the US Navy which takes CO2 directly from the ocean. Unfortunately it can't avoid being more expensive than fossil liquid fuels, which is why we have to campaign against exploration and drilling.
The article is vague. It says that the process recovers 100% of energy from plastics they tested. What plastics did they test? Also, there isn't a discussion on energy efficiency of the process.
How effective is it at converting plastic contaminated with food waste. The vast majority of plastic from my household is food packaging which is really quite expensive to decontaminate.
Turning plastic into fuel is probably the only practical way to re purpose it.
Food, different feed-stock, ect, are all small details when you're operating at high T needed to cleave bonds to make fuel. Cleaved bond -> food molecule is no longer food
Recycling never cleaves any bonds, so the food is still there causing problems.
Food, different feed-stock, ect, are all small details when you're operating at high T needed to cleave bonds to make fuel. Cleaved bond -> food molecule is no longer food
Recycling never cleaves any bonds, so the food is still there causing problems.
That can be autoclaved off, probably in the same process.
This is the kind of project the fossil industry would invest in. What we need instead is industry transformation away from fossils to renewables.
Isn’t this just burning more fossil fuels?
If some of the jet fuel comes from plastic waste instead of from the ground that might result in burning less fossil fuel, compared to the situation in which the plastic waste goes into landfill. However, as long as people are still burning coal to make electricity (which still happens in China, India, Australia, ....) I suspect that even less carbon would be released into the atmosphere if the plastic waste were burnt in a power station rather than turned into jet fuel.
How much would be released if it were just put into landfills?
No idea, really, but generating electricity by burning plastic might release less carbon than from burning coal because the plastic contains hydrogen as well as carbon. It depends, no doubt, on the type of plastic and the efficiency with which it can be burnt while avoiding the release of nasty chemicals.
It's not at all obvious to me what's best: landfill, burn, or recycle. But government policy should be based on a proper analysis of those options. I have the impression that government is mostly just compromising between what industry lobbyists are asking for, in order to maximise their profits, and what the ignorant public are asking for, in response to fashion and irrationality. Let's hope that somewhere some sensible civil servants are quietly doing the right sums.
It's not at all obvious to me what's best: landfill, burn, or recycle. But government policy should be based on a proper analysis of those options. I have the impression that government is mostly just compromising between what industry lobbyists are asking for, in order to maximise their profits, and what the ignorant public are asking for, in response to fashion and irrationality. Let's hope that somewhere some sensible civil servants are quietly doing the right sums.
> generating electricity by burning plastic might release less carbon than from burning coal because the plastic contains hydrogen as well as carbon
Can we get the same effect from burning coal while adding external hydrogen?
Can we get the same effect from burning coal while adding external hydrogen?
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