Those much maligned plastic grocery bags can run your diesel truck or car

plastic_bagFrom the University of Illinois at Urbana-Champaign

Plastic shopping bags make a fine diesel fuel, researchers report

CHAMPAIGN, Ill. — Plastic shopping bags, an abundant source of litter on land and at sea, can be converted into diesel, natural gas and other useful petroleum products, researchers report.

The conversion produces significantly more energy than it requires and results in transportation fuels – diesel, for example – that can be blended with existing ultra-low-sulfur diesels and biodiesels. Other products, such as natural gas, naphtha (a solvent), gasoline, waxes and lubricating oils such as engine oil and hydraulic oil also can be obtained from shopping bags.

The team produced equivalents of (from left to right, in vials) gasoline, diesel #1, diesel #2, and vacuum gas oil.
Credit: L. Brian Stauffer

A report of the new study appears in the journal Fuel Processing Technology.

There are other advantages to the approach, which involves heating the bags in an oxygen-free chamber, a process called pyrolysis, said Brajendra Kumar Sharma, a senior research scientist at the Illinois Sustainable Technology Center who led the research. The ISTC is a division of the Prairie Research Institute at the University of Illinois.

“You can get only 50 to 55 percent fuel from the distillation of petroleum crude oil,” Sharma said. “But since this plastic is made from petroleum in the first place, we can recover almost 80 percent fuel from it through distillation.”

Americans throw away about 100 billion plastic shopping bags each year, according to the Worldwatch Institute. The U.S. Environmental Protection Agency reports that only about 13 percent are recycled. The rest of the bags end up in landfills or escape to the wild, blowing across the landscape and entering waterways.

Plastic bags make up a sizeable portion of the plastic debris in giant ocean garbage patches that are killing wildlife and littering beaches. Plastic bags “have been detected as far north and south as the poles,” the researchers wrote.

“Over a period of time, this material starts breaking into tiny pieces, and is ingested along with plankton by aquatic animals,” Sharma said. Fish, birds, ocean mammals and other creatures have been found with a lot of plastic particles in their guts.

Whole shopping bags also threaten wildlife, Sharma said.

“Turtles, for example, think that the plastic grocery bags are jellyfish and they try to eat them,” he said. Other creatures become entangled in the bags.

Previous studies have used pyrolysis to convert plastic bags into crude oil. Sharma’s team took the research further, however, by fractionating the crude oil into different petroleum products and testing the diesel fractions to see if they complied with national standards for ultra-low-sulfur diesel and biodiesel fuels.

Shopping Bags to Oil: Used plastic shopping bags can be converted into petroleum products that serve a multitude of purposes. Credit: Julie McMahon

“A mixture of two distillate fractions, providing an equivalent of U.S. diesel #2, met all of the specifications” required of other diesel fuels in use today – after addition of an antioxidant, Sharma said.

“This diesel mixture had an equivalent energy content, a higher cetane number (a measure of the combustion quality of diesel requiring compression ignition) and better lubricity than ultra-low-sulfur diesel,” he said.

The researchers were able to blend up to 30 percent of their plastic-derived diesel into regular diesel, “and found no compatibility problems with biodiesel,” Sharma said.

“It’s perfect,” he said. “We can just use it as a drop-in fuel in the ultra-low-sulfur diesel without the need for any changes.”

###

The research team also included Bryan Moser, Karl Vermillion and Kenneth Doll, of the USDA National Center for Agricultural Utilization Research, in Peoria, Ill.; and Nandakishore Rajagopalan, of the ISTC at the U. of I.

The Illinois Hazardous Waste Research Fund, and the Environmental Research and Education Foundation supported this study.

Editor’s notes: To reach Brajendra Sharma, call 217-265-6810; email bksharma@illinois.edu.

The paper, “Production, Characterization and Fuel Properties of Alternative Diesel Fuel From Pyrolysis of Waste Plastic Grocery Bags,” is available online or from the U. of I. News Bureau.

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Goldie

This is hardly new.

Goldie

Sorry first response was a bit rude. Pyrolysis as a technology has been around for a long time. The problem with plastic bags is not that they can’t be converted to something else, but that sometimes they “escape” into the environment where they can cause havoc.
Waste to energy (or liquids) is a very promising technology that promises to be a “sustainable” energy source by taking what is otherwise trash and converting it to synthetic gas (syngas) or liquids generated form the syngas. In some cases pyrolysis can generate liquids directly from the source material.
The key hurdles to this sort of technology outside of the lab is that the input stream can be highly variable and pyrolysis itself is quite sensitive to such things. There are other forms of waste to energy technology though.
Another hurdle is that in some places the green movement insists that such technology is just another form of incineration and therefore polluting. They conveniently forget that incineration is happening without incident on most continents.
Another furphy is that they insist that all waste streams should be reduced, reused, recycled so that nothing is left for waste to energy technology to deal with. This is a somewhat utopian dream to say the least.

Josh Matthews

If this blog is one hundred percent accurate I do not understand why it is not a law to recycle things such as plastic bags. If we can get up to eighty percent of use back from plastic bags there is no excuse. With that much of reuse America would not have to depend on other countries. People complain about the prices yet they do not want to be part of the solution. If America recycled everything possible not only would prices of many things be lower but we would also be saving the planet. If everyone does their part they can make a difference.

Almost all of the plastic bags I get are used as trash bags, so they couldn’t easily be extracted for use.

Fred Love

With the average plastic bag weighing in at 5-10 grams, the 10 billion discarded each year might be pyrolysed to around 50,000 tonnes of fuel. Sounds a lot until you realise that this amount would fuel the US for about 15 minutes. And how much of that fuel would be used in collecting, baling, transporting and pyrolysing those bags? Just more “junk” science?

KevinK

“The key hurdles to this sort of technology outside of the lab is that the input stream can be highly variable and pyrolysis itself is quite sensitive to such things.”
When I first moved to a large city in upstate New York back in the early 1980’s they had just completed a “garbage to energy” converter. Quite an impressive building, lots of fancy pipes and whatnot sticking out on all sides. Theory was that we would be running out of “fossil” fuels about now, so they would just collect all that garbage and convert it to “energy” by sorting it and burning the “good bits”.
Funny thing about garbage, it usually stinks, and when you try to burn it as a fuel it stinks even worse….. After a few years they stopped trying to burn it because all the neighbors noticed that burning garbage smells like, well burning garbage. And another funny thing about garbage, it’s got lots of “hard bits” in it, seems they could never quite get the conveyors and other mechanisms sturdy enough to handle the odd chuck of pipe, or old bolt that some folks just seem to consider as “garbage”. Darned if the fancy “sorting” mechanism didn’t jam up every other week or so and bust a fancy gear that took a few weeks to replace.
The fancy “garbage to energy” convertor building was torn down after 5 years or so, they kept the parking lot and the “tipple” where the trucks dumped all the “energy rich” garbage. Now they sort out the paper and plastics (with good old fashioned front end loaders) and bundle it up to be recycled. On a windy day you can easily run over quite a few plastic soda bottles in the street out front as a fun driving challenge (see how many you can nail or how many you can miss).
Cheers, Kevin

CodeTech

Josh Matthews:
I can’t tell if you’re being sarcastic or not.

why it is not a law to recycle things such as plastic bags.

How about because it’s a dumb idea, and a free country? I should be free to put property that I have purchased into a landfill, or reuse it for lunches, or whatever.

If we can get up to eighty percent of use back from plastic bags there is no excuse. With that much of reuse America would not have to depend on other countries.

So recycling plastic bags will somehow eliminate America’s dependence on foreign oil? Who knew! Apparently that dependency thing is a mere fraction of a percent of petroleum use!

People complain about the prices yet they do not want to be part of the solution.

Prices of what? Plastic bags? I don’t know about there, but they screw us for 5 cents each here.

If America recycled everything possible not only would prices of many things be lower but we would also be saving the planet.

This is my favorite one. “Saving the Planet”. From what, exactly? The planet is just fine, it really doesn’t need to be saved. Recyclers are delusional.

If everyone does their part they can make a difference.

Really, no. No difference, whatsoever. But they can feel like they’re making a difference, and after all, isn’t that all that counts?

Pamela Gray

For me a lot of what I throw away is packaging that I find really irritating. Why can’t I buy from bins? Why do school scissors come in a flat package I can’t open and is 100 times bigger than the scissors? Why does everything that is already IN an irritating package, need to be bagged again? Here’s an idea. Let’s just stop bagging groceries and “stuff”. It would not be long before people started bringing something from home to carry the stuff in.

Don Gleason

I have a 90-pound lab who poops a lot….plastic bags are great…need i say more?

Streetcred

^Codetech … the cost of recycling is horrific. Our municipality has had separated garbage collection for many years … and most of it is still stored in huge outdoor ‘mountains’ and unrecycled. We use the plastic bags, all now required to be ‘biodegradeable’, for our kitchen waste so there goes the idea for recycling for synfuel.

Ack

Why is it the greenies always ignore the over-packaged stuff that goes in the bags?

Adam

@Pamela Gray
The reason why is because market research tells the suppliers that that is what people like. I do not like it either, but they think that people in general do like it.
But I do not want to have to take bags with me to go shopping. Often I will shop because I am out and feel like it. Would you have me never leave home without a bag just in case I decide to buy something! No. Of course not.
I like that I do not have to carry bags around with me. So thanks, but no thanks.
If the bags really were worth recycling then companies would be offering to buy them from us so that they could make a profit. The reality is that it is cheaper to make a new bag than it is to recycle one. Hence why they end up in landfill and new one are being made all of the time. Landfill is not running out, there is plenty of space for landfill and there is no problem with landfill. The whole plastic bag issue is no issue at all!

trafamadore

An old friend of mine, now passed away, from Dow Chemical, used to always be amazed that people burned oil. He said that when the oil is hard to come by, we can use fusion or sun to run our machines, but we won’t be able to make plastic forks.

u.k.(us)

I can’t believe this …came out of a university.
Even worse, a university in my home state.
Plastic bags ?, as an energy source, ya gotta be kidding me.

“The researchers were able to blend up to 30 percent of their plastic-derived diesel into regular diesel, “and found no compatibility problems with biodiesel,” Sharma said.

Ya but, biodiesel is expensive and in too short of supply to feed the needs of a healthy economy.
Do things like this even register at the university level anymore ?
I guess not.

Catcracking

First, I support recycling even though it has become very costly.
Just think how much weight is in all the plastic bags you use in one day versus the weight of the fuel you use each day in your auto, home heating, etc. to get a handle on the contribution to our liquid energy pool.
The claims are obviously over the top. One example below of a false claim:
“You can get only 50 to 55 percent fuel from the distillation of petroleum crude oil,” Sharma said. “But since this plastic is made from petroleum in the first place, we can recover almost 80 percent fuel from it through distillation.”
I think he makes the misleading claim mentioning the distillation process which is just the first stage of the refining process. Are they not aware of the extensive refining processing after initial distillation?
How much of crude is actually turned into useful fuel?
http://wiki.answers.com/Q/What_percentage_of_crude_oil_is_used_for_petrol
“47% gasoline for use in automobiles 23% heating oil and diesel fuel 18% other products, which includes petrochemical feedstock-products derived from petroleum principally for the manufacturing of chemicals, synthetic rubber and plastics 10% jet fuel 4% propane 3% asphalt (Percentages equal more than 100 because of an approximately 5% processing gain from refining)”
Not one smidgen of crude energy goes unused. Some energy may be used to provide heating energy to the refinering process.
One well know in the industry is that as the Carbon and hydrogen molecules are rearranged due to catalytic processing; therefore. the product volume is actually increased over the initial volume. Also H2 is added during many processes which is normally produced from natural gas..
Normally a lot of external energy is required in a pyrolysis (such as Natural gas) unless the feed is used to produce heat. Also most pyrolysis processes require a lot of clean up to produce an acceptable fuel. This has 17% solids in the product which must be disposed. This is not quantified in the article. Also the energy used to collect and distribute the product needs to be considered.

Outtheback

It is easy to become too skeptical these days.
Fred is correct the numbers sound enormous but when you really think about it it is nothing in the big picture and the real return even less.
CodeTech is right also, there is hardly any difference but it makes one feel good.
There is a European country that has a saying that translates to something like this:
“if you don’t look after the pennies you are not worth the dollars”
Every bit helps and that is why it is good that people keep looking at these things.
In my opinion we are better off to burn all non metallic/toxic/glass rubbish and turn it into energy rather then landfill, at least we get a return straight away and it is just about all gone and the ashes can be fertilizer.
But there will be people who feel that that generates too much of that plant growing gas.

CNC

Fred Love says:
February 12, 2014 at 8:10 pm
With the average plastic bag weighing in at 5-10 grams, the 10 billion discarded each year might be pyrolysed to around 50,000 tonnes of fuel……
I was just doing the math and came up with a similar number but used the articles 100 billion bag number so about 500,000 tonnes, still a drop in the bucket for the costs and energy input involved. I agree with the rest of you post as well.
I live in Singapore and we have a very good solution to the plastic bag problem. First people do not litter here, the littering laws are enforced and the fines are very high. Second is it is very hard to buy plastic trash bags here and that is because most everyone uses plastic shopping bags here to trash can liners. Third is our trash all goes to a very high tech, high temperature, incinerator that burns the trash and produces electricity with almost no pollution. The ash is used in road construction and land reclamation projects. Over all a very good use of plastic bag resource and much, much cheaper then turning them into diesel.
http://app2.nea.gov.sg/energy-waste/waste-management/waste-to-energy-(wte)-incineration-plants

Dr. Bob

The problem with recycling plastics is segregation. Universities can use graduate students to separate trash, but the real world must pay workers. So trash has a cost to sort into useful and un-useful residue. And if you don’t get just what you want, you end up with something like fluorine or chlorine in the fuel. That would not be a good day for an engine using that fuel.
So, if you want to do this, the process should be able to handle the bad trash along with the good. Right now companies are working on gasification of MSW (generally segregated) to produce CO/H2 (syngas) that can easily be cleaned of contaminants, converted into hydrocarbons using Fischer-Tropsch chemistry, and produce drop-in hydrocarbon fuels, generally diesel and jet, but also solvents and lubricant grade base oils. This is ultimate a better way to recycle all carbon-containing waste compared to focusing on just ethylene or propylene derived products.
The major hurdle is making such projects economically viable without government subsidy. It can be done, but it is capital intensive. But the reduction in land fill mass is significant as only the non-carbon waste need be landfilled.

People forget that plastic bags were popularized because paper bags were demonized. The [false] message was that paper bags were made from thousand year old redwood trees, or similar. The public was made to feel guilty for using paper bags [which are made from trees that are farmed just like any other crop].
So now we’re supposed to stop using plastic bags?
I happen to like them. They get a second use in our house, for cleaning the buried treaures out of the cat’s litter box. I consider that recycling! ☺

Lew Skannen

“The conversion produces significantly more energy than it requires ”
That alone will spoil the fun as far as the gesture-politics eco-nuts are concerned. Where is the self harm? Where is the sacrifice? Where is the hair shirt??!!

wayne Job

I go BS and a waste of time on this one. Problem is if your dear leader gets a sniff of this he may pass a law mandating 30% recycled plastic in your diesel fuel, then fine companies for not complying. wether it is available or not.

TheRealWorld

I have a solution. Just go back to paper bags. They are from a renewable resource. They break down quickly in the environment. They leave behind organic matter that is good for fertilizer. They could be burned for fuel, with by products of CO2 (good for plants), and ash which again can be used for fertilizer. Tell me again why paper bags are just so bad for the environment. Exactly how many turtles, fish, and wildlife were killed by paper bags? The paper bags that were being made before the bans were pretty good. I actually never threw any away that I got, since I found so many useful ways they were beneficial for my life. Plastic bags are cheaper, but they are definitely not better, or less harmful than paper bags, which are actually good for the environment. Why were plastic bags ever considered “Good”, by the environmentalist in the first place. When they used to ask, “Paper or plastic?”, I always said “Paper please.”

Glenn

Pamela Gray says:
February 12, 2014 at 8:46 pm
“For me a lot of what I throw away is packaging that I find really irritating. Why can’t I buy from bins? Why do school scissors come in a flat package I can’t open and is 100 times bigger than the scissors? Why does everything that is already IN an irritating package, need to be bagged again? Here’s an idea. Let’s just stop bagging groceries and “stuff”. It would not be long before people started bringing something from home to carry the stuff in.”
They do, called pants pockets and purses. Just kidding. Well not entirely. And there are
reasons manufacturers package the way they do. It isn’t that they want to make your life
miserable, or spend more than they need to on packaging.
But I think what you propose is already being forced in some jurisdictions.
I personally don’t like the idea. What if I decide to get a few extra coconuts? How many bags should I bring with me, or should I just use the front of my shirt?
http://usnews.nbcnews.com/_news/2012/05/16/11720480-hawaii-first-state-to-ban-plastic-bags-at-checkout?lite

Tim Wainwright

I think I’ll keep using my leftover bags and trash in the DeLorean. Mr Fusion is far easier than this.
🙂

Don K

If one recycles or reuses this stuff — which responsible folks really should do — one will quickly find that these bags are astonishingly light in weight. It’s going to take an awful lot of them to make much fuel or chemical feedstock.
Also, the bags are, Wikipedia assures me, mostly polyethylene — which means they are probably mostly made from natural gas or natural gas liquids (NGLs — propane, ethane,butane) not petroleum. Not that it matters all that much in the great scheme of things.
And, as someone points out above, the amount of non-biodegradable and often not easily recycled packaging used in modern products is truly appalling. Much, not all, of that packaging could be degradable, recyclable or omitted entirely
BTW, in my part of the world, reusable shopping bags sell for about a buck. They last for years, and hold more than most folks can (or wish to) lift, Using them doesn’t entirely cut out the use of plastic bags, but it much reduces it.

rogerknights

Pamela Gray says:
February 12, 2014 at 8:46 pm
For me a lot of what I throw away is packaging that I find really irritating. Why can’t I buy from bins? Why do school scissors come in a flat package I can’t open and is 100 times bigger than the scissors?

It’s to deter shoplifting.

Let’s just stop bagging groceries and “stuff”. It would not be long before people started bringing something from home to carry the stuff in.

In Seattle, Safeway now charges a quarter for each large, sturdy plastic bag. I recycle them by bringing them back into the store for reuse on the next visit. They’re superior to cloth totes in that they can be rinsed out–and they don’t harbor and incubate bacteria. Washing cloth totes consumes enough energy to make using them self-defeating from a green perspective. Plus, they hold only 2/3 or less of what the new sturdy plastic bags do.
(I acquired a large supply of the old flimsy plastic bags before they were phased out, to hold my garbage.)

Chad Wozniak

Recycling of plastic bags would seem to be preferable to the petty tyranny of municipalities banning the bags. If you recycle plastic bottles, why not bags? Just encourage people to do it – and DON’T FORCE THEM TO USE PAPER BAGS THAT ARE DIFFICULT FOR HANDICAPPED PEOPLE TO HANDLE OR SO-CALLED REUSABLE BAGS THAT ARE NOTHING BUT CONDUITS FOR FOOD-BORNE DISEASE. As a handicapped, immune-compromised person myself (survivor of leukemia and a bone marrow transplant), I resent the hell out of some narcissistic city councilperson making needless difficulties for me, and even endangering me (and others in similar circumstances) just to prove they can. Ever try to handle a paper grocery bag when you’re using a walker? Have you got a 300-degree steam press in your house to sterilize “reusable” bags? (Washing machine won’t do it even with chemicals.) Banning the bags is just another display of environmentalist tyranny, tied in like everything else with AGW.

Chad Wozniak

@rogerknights –
Who pays for the extra cost incurred by lower-income people for the bags? A quarter as bag may not seem like much to well-to-do people, but for little grandma in the bad neighborhood already having to choose between feeding the grandkids she’s raising and paying her electric bill, it’s just another unreasonable hardship and burden to bear. Seems to me the people who advocate these reusable bags should reimburse their cost to the people victimized by them. Wealthy leftists never think about what their “environmental” and “energy” policies do to poor people – they don’t feel a 25c bag, but little grandma s does, and her grandkids do.

brians356

Oh irony of ironies: Our new “single-stream” recycling system from Waste Management specifically prohibits plastic bags from the recycling bin! I must to put the plastic bags in the regular waste with any liquids and loose food waste – they go straight into the landfill.

u.k.(us)

When might this guilt trip stop ?
I already put twice (maybe 3 times) the mass into the recycle bin as the landfill bin.
I drive around in my dread SUV (it snows in Chicago),I see the garbage the pigs have thrown out their windows.
When it lands in front of my house I put it in the recycle bin.
I’m not doing any damage, and don’t feel guilty about the plastic garbage bags I send to the landfill, lest they escape my recycle bin, and start blowing around the neighborhood.
If you really want to turn them into fuel, I’ll save them for you, knowing it makes YOU feel better.

John F. Hultquist

wayne Job says:
February 12, 2014 at 9:45 pm
“I go BS and a waste of time on this one. Problem is if your dear leader gets a sniff of this he may pass a law mandating 30% recycled plastic in your diesel fuel, then fine companies for not complying. wether it is available or not.

The problem with Wayne’s statement is that a person might read this and think he is just trying to be funny. Maybe he is trying to be funny. Still, the reader ought to know the USA has already tried this sort of thing with a cellulosic biofuel mandate.
http://www.prnewswire.com/news-releases/court-strikes-down-cellulosic-biofuel-mandate—finds-epa-exceeded-statutory-authority-188400251.html

negrum

I feel that the biggest practical effect of recycling is that the concept of “waste not want not” is reinforced in the younger generation.

Stonyground

In the UK the supermarkets sell more robust bags that can be re-used. I always have several of these in the car and I take them with me whenever I shop. I have not used a disposable plastic shopping bag in years.

Not true that plastic bags “sizeable portion of the plastic debris in giant ocean garbage patches that are killing wildlife”.
According to the Plastics At Sea Project: “In most cases it is impossible to know what kind of object the plastic pieces came from. The most recognizable pieces are fragments of fishing line and industrial resin pellets (the “raw material” of consumer plastic products).”
http://progcontra.blogspot.co.uk/2013/09/carrier-bag-scepticism.html

D. J. Hawkins

@Catcracking says:
February 12, 2014 at 9:09 pm
Depending on the quality of the crude, 20 – 35% of the energy value of the feed is burned just to distill the crude.

pat

i re-use my plastic bags in a myriad of ways.
what i can say is, for a year or so, every person at my local supermarkets were using the fabric ones sold by the stores, & now i never see those bags. no doubt they got grubby & people got sick of washing them & so on.

David, UK

Josh Matthews says:
February 12, 2014 at 7:56 pm
I do not understand why it is not a law to recycle things such as plastic bags.

Because America is not (yet) a fascist country.
If America recycled everything possible not only would prices of many things be lower but we would also be saving the planet.
Seriously? Everything possible? Firstly, some things are in abundance and do not need to be recycled. There is enough oil to last so many generations into the future that we have plenty of time to develop alternative technology by the time it runs out. A bit like when we transitioned from the horse and cart. Secondly, recycling often requires multi-fold more energy (not to mention chemicals to break the thing down) than to simply produce something new from raw materials. Try a little research outside of your “save the planet” camp. Start with some science.

James Bull

I have found a use for all the carrier bags I get.
I put my shopping in them the next time I go to the shops, only when they are falling to bits do I get another. I do the same with the paper bags from the green grocers.
James Bull

rogerknights

Chad Wozniak says:
February 12, 2014 at 10:12 pm
@rogerknights –
Who pays for the extra cost incurred by lower-income people for the bags?

I need about four bags to hold $80-worth of groceries. Since (as I mentioned) I re-use them when I return to the store, that’s a one-time cost of only $1. That’s bearable.

tagerbaek

Where I come from, trash is burned in power stations. Back when plastic bags were free, the bags would help fuel the fire automatically. Then they put green taxes on the bags, so now they have to pour oil on the fire to keep it going.

Alan the Brit

Adam says:
February 12, 2014 at 8:57 pm
That is ALL part of the Command & Control process. To make everyone feel guilt about living! That we’re damaging the “environment” as a result of our modern lifestyles! So it’s perfectly natural after watching a few David Attenborough programmes, to feel “less” guilt by us “all doing our little bit!”. In fact the eco-stalinists despite their pretence to support “the science”, that’s the stuff that supports their narrow view of life, actually hate science & engineering, because Human resourcefulness & ingenuity solve problems that are brought to our attention! The just hate that kind of thing because there’s another scare story biting the dust!
Outtheback: It’s a British saying….”look after the pennies & the pounds will look after themselves!”
😉

John Moore

Out the back says…….”Look after the pennies and the pounds will look after themselves” is the old English proverb. Interpreted by the young now as… Never mind settling the credit card, just sign up for another one and transfer the balance. The shock comes in a year or three when this has been done a dozen times and quite a bit of interest has built up…. Me, here in England and very old shall try to stick to the old ways! Such pleasant memories of when I was made so welcome by eveyone I met in Chicago some years ago and in the then prosperous Detroit.

Gail Combs

Fred Love says: @ February 12, 2014 at 8:10 pm
With the average plastic bag weighing in at 5-10 grams, the 10 billion discarded each year might be pyrolysed to around 50,000 tonnes of fuel. Sounds a lot until you realise that this amount would fuel the US for about 15 minutes. And how much of that fuel would be used in collecting, baling, transporting and pyrolysing those bags? Just more “junk” science?
>>>>>>>>>>>>>>>
The real problem is the cost of collection and processing.
Plastics can be recycled too but you chop up the chain lengths and have Polyethylene or Polypropylene =======> Candle wax. So this is actually a better idea.
The last problem is idiot regulators. The plastics company I worked for, as the last process step stripped the short chain polymers from the plastic. This produced a liquid called “Waste oil” that made dandy fuel. We were going to put in an electric generator and use the “Waste oil” to produce electricity. The state said NO, it was a toxic waste (It wasn’t) and had to be disposed of by a company called Clean Harbors.
Even worse, a sister plant we had just purchased had the technology that would allow our ‘Waste oil’ to be used as feed stock. Again the state said NO! it was ‘Waste’ from an industrial process hand had to be disposed of as waste by Clean Harbors.
Our process was not good at conversion so only about half of the monomer got converted. That was a heck of a lot of good clean oil that got incenerated as ‘Waste’
Having the mind numbing task of dealing with idiotic regulators and worse than useless regulations in the state of Taxachusetts and seeing the useless waste in time, money and raw materials just about turned me into an Anarchist!

How long before there is a federally subsidized program to produce plastic bags just to convert them to diesel fuel?

dipchip

“You can get only 50 to 55 percent fuel from the distillation of petroleum crude oil,” Sharma said. That’s Mann talk if I ever heard it. Crude on average refines to 46% Gasoline, 31% Distillate, 9%Jet Fuel, add residual fuel and propane and you are over 90% Yield. See link
http://www.eia.gov/dnav/pet/pet_pnp_pct_dc_nus_pct_m.htm
Check the answers to some energy questions.
http://www.eia.gov/tools/faqs/faq.cfm?id=24&t=10

By the way … talking about diesel fuel. It seems that the ‘winter’ grade diesel fuel being sold in the United States is only good down to -20 Celsius (-4F). In colder temps the diesel ‘gels’ and clogs the fuel filters. Maybe the bio-fuel mixed in to it has something to do with it. .. In places like Montana there aren’t any signs at the truck stops to warn the truckers, even if the temps *are lower than -20C. … If you are interested a trucker is complaining about it here :- http://www.youtube.com/watch?v=4PswiYmEIgg

aaron

Do they consider the cost of collecting and transporting the bags?

johnmarshall

I always proposed that burning rubbish, including plastic bags, to produce electricity was better than landfill. This is an even better idea. Not sure if it is ”NEW” though.

dipchip

Many plastic bags are made from corn and turn to dust in a few years.

For those promoting paper bags over those cheap T-Shirt style plastic bags… To make an equivalent paper bag takes about ten (10) times the energy. As for paper bags deteriorating in the anaerobic atmosphere of a landfill — I don’t thinks so. I would give references — but the information is widely available via google search. Yes I have consulted to both the plastic and paper industries.
Yes plastic bags do deteriorate — a little corn starch does it.