Author Topic: How to recycle plastics  (Read 3148 times)

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Offline strawberryTopic starter

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How to recycle plastics
« on: August 02, 2022, 05:27:48 pm »
Some say it is impossible/expensive/needs new tech
Jobs are more important than short term profit gains
 

Online ataradov

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Re: How to recycle plastics
« Reply #1 on: August 02, 2022, 05:50:09 pm »
This whole thing hinges on everyone washing the plastic. And by the looks of it, washing it pretty well. While not impossible, this goes against the "idea" of this packaging, and may be hard to implement in other places.

Also, this is clearly not washable in a washing machine, so a manual wash would be needed. This would consume a fair bit of water.

There has to be a better solution. Like reusable containers and utensils.
Alex
 
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Offline strawberryTopic starter

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Re: How to recycle plastics
« Reply #2 on: August 02, 2022, 09:50:03 pm »
they wash plastics in factory anyway and reuse filtered water
There has to be a better solution. Like reusable containers and utensils.
manual washing anyway.
single use stuff is on consumer expense
reusable would be inevitably on company expense.. hiring more people , lowering profit margins
someone like mcdonalds wont return to 20's century
 

Online langwadt

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Re: How to recycle plastics
« Reply #3 on: August 02, 2022, 11:26:05 pm »
as long as we are burning fossil fuel to make heat and electricity, just incinerate the plastic to make heat/electricity, it is basically oil anyway
 
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Offline abquke

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Re: How to recycle plastics
« Reply #4 on: August 02, 2022, 11:28:16 pm »
According to my latest print copy of the IEEE Spectrum, AI will fix recycling forever because AI.
 
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Offline SmallCog

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Re: How to recycle plastics
« Reply #5 on: August 03, 2022, 03:50:23 am »
I have a (possibly half baked) theory that the solution to a lot of waste is to put pressure on the suppliers through the retailers because unfortunately much of our world is driven by cost, and sometimes the worst environmental options in packaging are the cheapest.

My example store could be anything from Costco to Ikea to Aldi to Walmart or whatever other bit of everything store you have in your bit of the world. I want to put the onus on them to push for better packaging options by making it compulsory that they as the retailer accept packaging back at the store, comingled (unsorted).

So I go home from the shop with my new gadget, it comes in a cardboard box, wrapped in a plastic bag, with polystyrene brick padding. The shop also sells food and I buy some stuff that's tinned as well as a chocolate bar and a drink in a bottle.

Next time I go back to the store on my way in I can just drop off the box with all of the packaging from all the items in it. They have to take it and they have to recycle it.

Suddenly large multinational retailers are putting pressure onto their suppliers to (for example) stop using polystyrene, its tricky to mechanically sort from other stuff and find a recycling stream for, use cardboard padding instead. Use a paper bag to wrap the item (if neccessary at all) in stead of a plastic bag as it can go into the same waste stream as the cardboard.

Mechanized sorting of (some) comingled recyclables is already possible, but there's no incentive to package goods in these easily sorted/recyclable materials.

Manufacturers will get on board pretty quick if large retailers say "we're dropping your products unless you change how you pack them" and they'll be saying that pretty quick once they're responsible for the packaging recycling.
 
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Offline pcprogrammer

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Re: How to recycle plastics
« Reply #6 on: August 03, 2022, 07:53:41 am »
There are almost 8 billion people in the world, but nobody want's to do this kind of work.

Basically due to the fact it does not pay well, and there is a social stigma on it because people look down on the people who do these kind of jobs.

Here in France we can put all our plastics and other recyclables, except glass, into a yellow bin and wheel it to the curb every other week. No idea what they do with it once collected. Since this was setup we only need to put the brown bin, with the other no recyclable waste, out at most twice a year. The yellow bin about once every 6 weeks.

So it is good for our conscience and we feel less guilty 8)

Offline Miyuki

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Re: How to recycle plastics
« Reply #7 on: August 03, 2022, 08:30:55 am »
There are almost 8 billion people in the world, but nobody want's to do this kind of work.

Basically due to the fact it does not pay well, and there is a social stigma on it because people look down on the people who do these kind of jobs.

Here in France we can put all our plastics and other recyclables, except glass, into a yellow bin and wheel it to the curb every other week. No idea what they do with it once collected. Since this was setup we only need to put the brown bin, with the other no recyclable waste, out at most twice a year. The yellow bin about once every 6 weeks.

So it is good for our conscience and we feel less guilty 8)
Here is what happens to the content of yellow bins across Europe
It is not as bad as I expected. Energy usage seems to be widespread

 
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Offline makingdevices

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Re: How to recycle plastics
« Reply #8 on: August 03, 2022, 09:24:07 am »
Still a big amount of landfill... No matter how good some countries are working, the problem won't be solved until everyone is working on it. Bad habits have way higher impact than good ones :/
 
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Offline strawberryTopic starter

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Re: How to recycle plastics
« Reply #9 on: August 03, 2022, 11:49:43 am »
oil refinery wont pileup its excess produced plastics
energy recovery is waste of fantastic material (corn based plastics are not as durable)
landfill is technically a large resource storage (except that ground water contamination part)

mark standard plastic material types with UV/IR ink -- do optical sorting -- chop -- wash -- dry -- melt

but noone would buy it if there is new quality material available or some fish net scraps
 

Offline abquke

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Re: How to recycle plastics
« Reply #10 on: August 03, 2022, 12:22:04 pm »
Relabel "landfill" as "carbon sequestration". Problem solved.
 
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Online langwadt

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Re: How to recycle plastics
« Reply #11 on: August 03, 2022, 12:39:27 pm »
oil refinery wont pileup its excess produced plastics
energy recovery is waste of fantastic material (corn based plastics are not as durable)
landfill is technically a large resource storage (except that ground water contamination part)

mark standard plastic material types with UV/IR ink -- do optical sorting -- chop -- wash -- dry -- melt

but noone would buy it if there is new quality material available or some fish net scraps

reusing plastic cost a lot of resourcesfor an inferior end product, glass and metal are recycled because it saves resources and the end product is just as good
 
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Online Ranayna

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Re: How to recycle plastics
« Reply #12 on: August 03, 2022, 01:41:19 pm »
Relabel "landfill" as "carbon sequestration". Problem solved.
That would only make any sense if the plastic that ends up in the landfill has been made from some organic material that was not sequestered eons ago.
 

Offline AndyBeez

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Re: How to recycle plastics
« Reply #13 on: August 03, 2022, 02:19:13 pm »
Picture this... 500kg of VHS video tapes. That is what my last company had as surplus media in one store room alone. As studious studio employees, we tried to get them recycled. Easy? Not one UK e-waste company would touch them.

The issue is a typical video cassette contains at least six different types of plastic, often welded together. Plus there are metal screws, rollers and springs. Finally the video tape medium is rich in nasty phenols and pcbs.

The advice we received from our local council's business waste officer was to send them all into landfill. This was safer than burning them which requires a special hazmat license.

Even disassembled, a video tape is uneconomic to reclaim. How many tonnes of unused video tapes are there around the world?

Maybe we should have shipped them all back to JVC/Panasonic/Sony in Japan?
« Last Edit: August 03, 2022, 02:22:05 pm by AndyBeez »
 

Online Zero999

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Re: How to recycle plastics
« Reply #14 on: August 03, 2022, 02:28:22 pm »
Picture this... 500kg of VHS video tapes. That is what my last company had as surplus media in one store room alone. As studious studio employees, we tried to get them recycled. Easy? Not one UK e-waste company would touch them.

The issue is a typical video cassette contains at least six different types of plastic, often welded together. Plus there are metal screws, rollers and springs. Finally the video tape medium is rich in nasty phenols and pcbs.

The advice we received from our local council's business waste officer was to send them all into landfill. This was safer than burning them which requires a special hazmat license.

Even disassembled, a video tape is uneconomic to reclaim. How many tonnes of unused video tapes are there around the world?
Thermal depolymerisation could be used to turn them back into crude oil. In theory it should work with any organic material, including dead bodies, but it's probably only economical to do so with plastic.

as long as we are burning fossil fuel to make heat and electricity, just incinerate the plastic to make heat/electricity, it is basically oil anyway
Gassification is another potential useful way to get energy from waste. The plastic and dry organic material is partially combusted to make carbon-monoxide, hydrogen and methane, which can power an internal combustion engine or turbine. This is more efficient that just burning them to create steam and it's easier to filter the fuel gas to remove the tar, than the flue gas.
 

Online langwadt

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Re: How to recycle plastics
« Reply #15 on: August 03, 2022, 02:39:43 pm »
Picture this... 500kg of VHS video tapes. That is what my last company had as surplus media in one store room alone. As studious studio employees, we tried to get them recycled. Easy? Not one UK e-waste company would touch them.

The issue is a typical video cassette contains at least six different types of plastic, often welded together. Plus there are metal screws, rollers and springs. Finally the video tape medium is rich in nasty phenols and pcbs.

The advice we received from our local council's business waste officer was to send them all into landfill. This was safer than burning them which requires a special hazmat license.

Even disassembled, a video tape is uneconomic to reclaim. How many tonnes of unused video tapes are there around the world?
Thermal depolymerisation could be used to turn them back into crude oil. In theory it should work with any organic material, including dead bodies, but it's probably only economical to do so with plastic.

as long as we are burning fossil fuel to make heat and electricity, just incinerate the plastic to make heat/electricity, it is basically oil anyway
Gassification is another potential useful way to get energy from waste. The plastic and dry organic material is partially combusted to make carbon-monoxide, hydrogen and methane, which can power an internal combustion engine or turbine. This is more efficient that just burning them to create steam and it's easier to filter the fuel gas to remove the tar, than the flue gas.

how is adding more steps going to make it more efficient? generating steam and running steam turbines is very efficient, that is why pretty all powerplants do it ...

 
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Online Zero999

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Re: How to recycle plastics
« Reply #16 on: August 03, 2022, 05:30:14 pm »
Picture this... 500kg of VHS video tapes. That is what my last company had as surplus media in one store room alone. As studious studio employees, we tried to get them recycled. Easy? Not one UK e-waste company would touch them.

The issue is a typical video cassette contains at least six different types of plastic, often welded together. Plus there are metal screws, rollers and springs. Finally the video tape medium is rich in nasty phenols and pcbs.

The advice we received from our local council's business waste officer was to send them all into landfill. This was safer than burning them which requires a special hazmat license.

Even disassembled, a video tape is uneconomic to reclaim. How many tonnes of unused video tapes are there around the world?
Thermal depolymerisation could be used to turn them back into crude oil. In theory it should work with any organic material, including dead bodies, but it's probably only economical to do so with plastic.

as long as we are burning fossil fuel to make heat and electricity, just incinerate the plastic to make heat/electricity, it is basically oil anyway
Gassification is another potential useful way to get energy from waste. The plastic and dry organic material is partially combusted to make carbon-monoxide, hydrogen and methane, which can power an internal combustion engine or turbine. This is more efficient that just burning them to create steam and it's easier to filter the fuel gas to remove the tar, than the flue gas.

how is adding more steps going to make it more efficient? generating steam and running steam turbines is very efficient, that is why pretty all powerplants do it ...
Not necessarily. For example hybrid cars are more efficient than those with plain old internal combustion engines.

Fossil fuel power plants burn coal or gas, which are consistent and still much cleaner than plastic, which will be mixed with other rubbish.

When rubbish is just burned, it releases a large volume of toxic gasses, as well as the CO2 and H2O. The advantage of gasification is a smaller volume of syngas can be cleaned, before it's burned in an internal combustion engine, which will have a very clean exhaust because the fuel is so clean. Another advantage of gasification is the syngas can be stored, although that requires a lot of space as it becomes unstable at high pressures.

Internal combustion engines have a greater dynamic range and can be started and stopped fairly quickly. Turbines take awhile to get up and running and have to be run at a certain speed to achieve optimum efficiency.
 

Online tooki

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Re: How to recycle plastics
« Reply #17 on: August 03, 2022, 05:44:03 pm »
There are almost 8 billion people in the world, but nobody want's to do this kind of work.

Basically due to the fact it does not pay well, and there is a social stigma on it because people look down on the people who do these kind of jobs.

Here in France we can put all our plastics and other recyclables, except glass, into a yellow bin and wheel it to the curb every other week. No idea what they do with it once collected. Since this was setup we only need to put the brown bin, with the other no recyclable waste, out at most twice a year. The yellow bin about once every 6 weeks.

So it is good for our conscience and we feel less guilty 8)
Here is what happens to the content of yellow bins across Europe
It is not as bad as I expected. Energy usage seems to be widespread

Take that graph with a huge grain of salt: most likely, it counts as “recycling” to collect it for recycling and sending it abroad to be recycled (where it may not actually be recycled). What makes me suspect this is Germany’s positive appearance on this graph, while other sources I’ve seen (in various German-made documentaries) show that while recycling rates are high (in the sense of collection), huge amounts of plastics are not processed within Germany, but sent to Eastern Europe, which means they’re likely not actually getting recycled at all.

Switzerland is a huge outlier in this regard: aside from having very high rates of plastic collection (82%-95%, depending on who you ask), nearly all collected plastic is also recycled within Switzerland, ensuring it’s actually recycled. (For PET, none is exported at all, apparently.) Since Switzerland does export plastic abroad (to Germany, mostly), that must be the non-PET plastics.
 
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Online Zero999

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Re: How to recycle plastics
« Reply #18 on: August 03, 2022, 05:54:04 pm »
There are almost 8 billion people in the world, but nobody want's to do this kind of work.

Basically due to the fact it does not pay well, and there is a social stigma on it because people look down on the people who do these kind of jobs.

Here in France we can put all our plastics and other recyclables, except glass, into a yellow bin and wheel it to the curb every other week. No idea what they do with it once collected. Since this was setup we only need to put the brown bin, with the other no recyclable waste, out at most twice a year. The yellow bin about once every 6 weeks.

So it is good for our conscience and we feel less guilty 8)
Here is what happens to the content of yellow bins across Europe
It is not as bad as I expected. Energy usage seems to be widespread

Take that graph with a huge grain of salt: most likely, it counts as “recycling” to collect it for recycling and sending it abroad to be recycled (where it may not actually be recycled). What makes me suspect this is Germany’s positive appearance on this graph, while other sources I’ve seen (in various German-made documentaries) show that while recycling rates are high (in the sense of collection), huge amounts of plastics are not processed within Germany, but sent to Eastern Europe, which means they’re likely not actually getting recycled at all.

Switzerland is a huge outlier in this regard: aside from having very high rates of plastic collection (82%-95%, depending on who you ask), nearly all collected plastic is also recycled within Switzerland, ensuring it’s actually recycled. (For PET, none is exported at all, apparently.) Since Switzerland does export plastic abroad (to Germany, mostly), that must be the non-PET plastics.
True and correlation doesn't mean causation. It might be that governments which invest in recycling, also have laws restricting landfill.
 

Offline strawberryTopic starter

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Re: How to recycle plastics
« Reply #19 on: August 07, 2022, 04:54:43 pm »
reusing plastic cost a lot of resourcesfor an inferior end product, glass and metal are recycled because it saves resources and the end product is just as good
pumped raw oil is basically : water, dirt, oil.
oil tankers burn crude oil because it is cheapest fuel ~3000m^3.

1: 1# oil refinery - product factory - garbage collection - garbage burning plant - garbage dump site - 2# oil refinery - product factory - garbage collection - garbage burning plant - garbage dump site
2: 1# oil refinery - product factory - garbage collection - recycle factory - 2# product factory - garbage collection - recycle factory ...     - garbage collection - garbage burning plant - garbage dump site

single use product must be top quality even when consumer cant tell difference
 

Online langwadt

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Re: How to recycle plastics
« Reply #20 on: August 07, 2022, 08:20:49 pm »
Picture this... 500kg of VHS video tapes. That is what my last company had as surplus media in one store room alone. As studious studio employees, we tried to get them recycled. Easy? Not one UK e-waste company would touch them.

The issue is a typical video cassette contains at least six different types of plastic, often welded together. Plus there are metal screws, rollers and springs. Finally the video tape medium is rich in nasty phenols and pcbs.

The advice we received from our local council's business waste officer was to send them all into landfill. This was safer than burning them which requires a special hazmat license.

Even disassembled, a video tape is uneconomic to reclaim. How many tonnes of unused video tapes are there around the world?
Thermal depolymerisation could be used to turn them back into crude oil. In theory it should work with any organic material, including dead bodies, but it's probably only economical to do so with plastic.

as long as we are burning fossil fuel to make heat and electricity, just incinerate the plastic to make heat/electricity, it is basically oil anyway
Gassification is another potential useful way to get energy from waste. The plastic and dry organic material is partially combusted to make carbon-monoxide, hydrogen and methane, which can power an internal combustion engine or turbine. This is more efficient that just burning them to create steam and it's easier to filter the fuel gas to remove the tar, than the flue gas.

how is adding more steps going to make it more efficient? generating steam and running steam turbines is very efficient, that is why pretty all powerplants do it ...
Not necessarily. For example hybrid cars are more efficient than those with plain old internal combustion engines.

in start-stop traffic sure, going down the highway not so much if at all


Fossil fuel power plants burn coal or gas, which are consistent and still much cleaner than plastic, which will be mixed with other rubbish.

When rubbish is just burned, it releases a large volume of toxic gasses, as well as the CO2 and H2O. The advantage of gasification is a smaller volume of syngas can be cleaned, before it's burned in an internal combustion engine, which will have a very clean exhaust because the fuel is so clean. Another advantage of gasification is the syngas can be stored, although that requires a lot of space as it becomes unstable at high pressures.

coal plants already need lots of exhaust cleaning, so it is a matter of cleaning the exhaust or the gas with the loss in efficiency from an extra step

Internal combustion engines have a greater dynamic range and can be started and stopped fairly quickly. Turbines take awhile to get up and running and have to be run at a certain speed to achieve optimum efficiency.

Internal combustion engines quickly lose efficiency at part load, even more so with gas turbines, and in any case they usually have to run at a certain speed because they have to generate 50/60Hz
 

Online Zero999

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Re: How to recycle plastics
« Reply #21 on: August 07, 2022, 08:55:35 pm »
Picture this... 500kg of VHS video tapes. That is what my last company had as surplus media in one store room alone. As studious studio employees, we tried to get them recycled. Easy? Not one UK e-waste company would touch them.

The issue is a typical video cassette contains at least six different types of plastic, often welded together. Plus there are metal screws, rollers and springs. Finally the video tape medium is rich in nasty phenols and pcbs.

The advice we received from our local council's business waste officer was to send them all into landfill. This was safer than burning them which requires a special hazmat license.

Even disassembled, a video tape is uneconomic to reclaim. How many tonnes of unused video tapes are there around the world?
Thermal depolymerisation could be used to turn them back into crude oil. In theory it should work with any organic material, including dead bodies, but it's probably only economical to do so with plastic.

as long as we are burning fossil fuel to make heat and electricity, just incinerate the plastic to make heat/electricity, it is basically oil anyway
Gassification is another potential useful way to get energy from waste. The plastic and dry organic material is partially combusted to make carbon-monoxide, hydrogen and methane, which can power an internal combustion engine or turbine. This is more efficient that just burning them to create steam and it's easier to filter the fuel gas to remove the tar, than the flue gas.

how is adding more steps going to make it more efficient? generating steam and running steam turbines is very efficient, that is why pretty all powerplants do it ...
Not necessarily. For example hybrid cars are more efficient than those with plain old internal combustion engines.

in start-stop traffic sure, going down the highway not so much if at all


Fossil fuel power plants burn coal or gas, which are consistent and still much cleaner than plastic, which will be mixed with other rubbish.

When rubbish is just burned, it releases a large volume of toxic gasses, as well as the CO2 and H2O. The advantage of gasification is a smaller volume of syngas can be cleaned, before it's burned in an internal combustion engine, which will have a very clean exhaust because the fuel is so clean. Another advantage of gasification is the syngas can be stored, although that requires a lot of space as it becomes unstable at high pressures.

coal plants already need lots of exhaust cleaning, so it is a matter of cleaning the exhaust or the gas with the loss in efficiency from an extra step

Internal combustion engines have a greater dynamic range and can be started and stopped fairly quickly. Turbines take awhile to get up and running and have to be run at a certain speed to achieve optimum efficiency.

Internal combustion engines quickly lose efficiency at part load, even more so with gas turbines, and in any case they usually have to run at a certain speed because they have to generate 50/60Hz
Have you actually bothered to read up about gasification, before attempting to debunk it? There are many reasons why it's preferable, than just burning the waste directly to generate heat. It's also used for coal. It's just more common for energy from waste because it can't be ground to a consistent powder like coal can.
https://en.wikipedia.org/wiki/Gasification
https://power.mhi.com/products/igcc
https://kleinmanenergy.upenn.edu/news-insights/waste-gasification-how-old-technology-can-solve-a-modern-problem/
 

Online langwadt

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Re: How to recycle plastics
« Reply #22 on: August 07, 2022, 10:41:10 pm »
Picture this... 500kg of VHS video tapes. That is what my last company had as surplus media in one store room alone. As studious studio employees, we tried to get them recycled. Easy? Not one UK e-waste company would touch them.

The issue is a typical video cassette contains at least six different types of plastic, often welded together. Plus there are metal screws, rollers and springs. Finally the video tape medium is rich in nasty phenols and pcbs.

The advice we received from our local council's business waste officer was to send them all into landfill. This was safer than burning them which requires a special hazmat license.

Even disassembled, a video tape is uneconomic to reclaim. How many tonnes of unused video tapes are there around the world?
Thermal depolymerisation could be used to turn them back into crude oil. In theory it should work with any organic material, including dead bodies, but it's probably only economical to do so with plastic.

as long as we are burning fossil fuel to make heat and electricity, just incinerate the plastic to make heat/electricity, it is basically oil anyway
Gassification is another potential useful way to get energy from waste. The plastic and dry organic material is partially combusted to make carbon-monoxide, hydrogen and methane, which can power an internal combustion engine or turbine. This is more efficient that just burning them to create steam and it's easier to filter the fuel gas to remove the tar, than the flue gas.

how is adding more steps going to make it more efficient? generating steam and running steam turbines is very efficient, that is why pretty all powerplants do it ...
Not necessarily. For example hybrid cars are more efficient than those with plain old internal combustion engines.

in start-stop traffic sure, going down the highway not so much if at all


Fossil fuel power plants burn coal or gas, which are consistent and still much cleaner than plastic, which will be mixed with other rubbish.

When rubbish is just burned, it releases a large volume of toxic gasses, as well as the CO2 and H2O. The advantage of gasification is a smaller volume of syngas can be cleaned, before it's burned in an internal combustion engine, which will have a very clean exhaust because the fuel is so clean. Another advantage of gasification is the syngas can be stored, although that requires a lot of space as it becomes unstable at high pressures.

coal plants already need lots of exhaust cleaning, so it is a matter of cleaning the exhaust or the gas with the loss in efficiency from an extra step

Internal combustion engines have a greater dynamic range and can be started and stopped fairly quickly. Turbines take awhile to get up and running and have to be run at a certain speed to achieve optimum efficiency.

Internal combustion engines quickly lose efficiency at part load, even more so with gas turbines, and in any case they usually have to run at a certain speed because they have to generate 50/60Hz
Have you actually bothered to read up about gasification, before attempting to debunk it? There are many reasons why it's preferable, than just burning the waste directly to generate heat. It's also used for coal. It's just more common for energy from waste because it can't be ground to a consistent powder like coal can.
https://en.wikipedia.org/wiki/Gasification
https://power.mhi.com/products/igcc
https://kleinmanenergy.upenn.edu/news-insights/waste-gasification-how-old-technology-can-solve-a-modern-problem/


"
A major challenge for waste gasification technologies is to reach an acceptable (positive) gross electric efficiency. The high efficiency of converting syngas to electric power is counteracted by significant power consumption in the waste preprocessing, the consumption of large amounts of pure oxygen (which is often used as gasification agent), and gas cleaning. Another challenge becoming apparent when implementing the processes in real life is to obtain long service intervals in the plants, so that it is not necessary to close down the plant every few months for cleaning the reactor.
"
 

Online Zero999

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Re: How to recycle plastics
« Reply #23 on: August 08, 2022, 07:23:20 am »
Picture this... 500kg of VHS video tapes. That is what my last company had as surplus media in one store room alone. As studious studio employees, we tried to get them recycled. Easy? Not one UK e-waste company would touch them.

The issue is a typical video cassette contains at least six different types of plastic, often welded together. Plus there are metal screws, rollers and springs. Finally the video tape medium is rich in nasty phenols and pcbs.

The advice we received from our local council's business waste officer was to send them all into landfill. This was safer than burning them which requires a special hazmat license.

Even disassembled, a video tape is uneconomic to reclaim. How many tonnes of unused video tapes are there around the world?
Thermal depolymerisation could be used to turn them back into crude oil. In theory it should work with any organic material, including dead bodies, but it's probably only economical to do so with plastic.

as long as we are burning fossil fuel to make heat and electricity, just incinerate the plastic to make heat/electricity, it is basically oil anyway
Gassification is another potential useful way to get energy from waste. The plastic and dry organic material is partially combusted to make carbon-monoxide, hydrogen and methane, which can power an internal combustion engine or turbine. This is more efficient that just burning them to create steam and it's easier to filter the fuel gas to remove the tar, than the flue gas.

how is adding more steps going to make it more efficient? generating steam and running steam turbines is very efficient, that is why pretty all powerplants do it ...
Not necessarily. For example hybrid cars are more efficient than those with plain old internal combustion engines.

in start-stop traffic sure, going down the highway not so much if at all


Fossil fuel power plants burn coal or gas, which are consistent and still much cleaner than plastic, which will be mixed with other rubbish.

When rubbish is just burned, it releases a large volume of toxic gasses, as well as the CO2 and H2O. The advantage of gasification is a smaller volume of syngas can be cleaned, before it's burned in an internal combustion engine, which will have a very clean exhaust because the fuel is so clean. Another advantage of gasification is the syngas can be stored, although that requires a lot of space as it becomes unstable at high pressures.

coal plants already need lots of exhaust cleaning, so it is a matter of cleaning the exhaust or the gas with the loss in efficiency from an extra step

Internal combustion engines have a greater dynamic range and can be started and stopped fairly quickly. Turbines take awhile to get up and running and have to be run at a certain speed to achieve optimum efficiency.

Internal combustion engines quickly lose efficiency at part load, even more so with gas turbines, and in any case they usually have to run at a certain speed because they have to generate 50/60Hz
Have you actually bothered to read up about gasification, before attempting to debunk it? There are many reasons why it's preferable, than just burning the waste directly to generate heat. It's also used for coal. It's just more common for energy from waste because it can't be ground to a consistent powder like coal can.
https://en.wikipedia.org/wiki/Gasification
https://power.mhi.com/products/igcc
https://kleinmanenergy.upenn.edu/news-insights/waste-gasification-how-old-technology-can-solve-a-modern-problem/


"
A major challenge for waste gasification technologies is to reach an acceptable (positive) gross electric efficiency. The high efficiency of converting syngas to electric power is counteracted by significant power consumption in the waste preprocessing, the consumption of large amounts of pure oxygen (which is often used as gasification agent), and gas cleaning. Another challenge becoming apparent when implementing the processes in real life is to obtain long service intervals in the plants, so that it is not necessary to close down the plant every few months for cleaning the reactor.
"
That applies to many energy from waste systems, not just gasification.  Its more of a problem for waste containing large amounts of water i.e. soiled nappies and medical waste, which requires large amounts of energy to dry, irrespective of whether it's burnt directly or gasified first.  It isn't an issue for dry waste such as plastics and biomass i.e. nut shells.

Getting net energy from gasification is easy using dry fuel. Pure oxygen isn't required.  It's an old technology first used to convert coal to provide gas to homes. It fell out of favour for cheaper, cleaner natural gas. There are numerous videos on YouTube of people running gasifiers to power vehicles and electric generators and it works very well.
 


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