How to turn plastic waste into diesel fuel cheaply

[silver]

And one more will a hot air gun or hot air blower can be used instead of the burner or coils?

[islander]

On the units I have seen they have a cyclone filter between the reactor and the fractionating vessels. there are feedback loops on the bottom of the cyclone and all the vessels back to the reactor, these feedback loops have valves to shut them down but I never was able to see them working and don't know what the operating procedure was.

I guess that the feedback on the cyclone was periodically opened to allow any condensate to return to the reactor, the other vessels may have had the valves open until operating temperature was reached and then closed.

So you had opportunity to see a real professionnal set up ? a petroleum refinery ? heavy oil visbreaking ?

please let me know.

seems to me the cyclone has to be properly sized to the gaz flux

seems hard to achieve... according to the liquid output, estimate the gaseous flux ? then build one and try it with compressed air at the same flux ?

input dust into the input flux to see if it works or not ?

seems a real art work ...



put water to remove oxygen :
it should work, in the plastic set up if have some room under the plastic, but you'll get this water condensed at the output with your diesel

with the oil (wmo) set up I think it's not good : water is heavier than oil, so will go under. and when boiling, it would spill wmo everywhere, contaminating the output with feedstock wmo

Master Jetijs wrote :

Might be a great idea to combine the thermal cracking with a plasma gas processor.

do you mean in order not to obtain paraffins or heavy fractions form the plastic ?

my experiences shown a gaz can be cracked too, so you can overheat the output pipe, with a flame (why not to use your wasted flu gaz in a good burner) and then the parameters to adjust would be : volume of overheated pipe, temperature reached.

or you could condensate the first heavy fraction and send it again to the boiler to crack again. it works.

[islander]

oil set up pictures !

maybe needed to register at the forum to view that.

Oil To Diesel Photo Gallery - Version 1.0

[Boston]

absolutely outstanding

I'm in

I build a lot of stuff and this thing is now on the top of the list. I believe the process is called pyrolysis when you disassociate materials using heat in an oxygenless environment, also if I remember the correct temp to get diesel out of plastic is about 400°F but its been a long time. My apologies as I've not read the entire thread yet but the simplicity of this system is spectacular, I pretty much did a backflip having seen the video. The electrical element makes controlling the temp look very easy and all in all its a must have but I'll probably make a larger one. Two kilogram pr liter and I want about 100 liters pr cycle means 200kg capacity in which case I should size the thing to accept blocks from cheap recycled trash compactor. But size maters when calculating efficiency on a device like this one.

I presently run my truck on a variety of waste oils some of which I can process on board



just last weekend I threw together this steamer for a project I'm working on



So the idea of welding up a few more bits and pieces into this thing is not so far fetched and its got huge potential. I love the idea of running a boat on waste plastic which could be collected from just about any beach, specially in places like Hawaii and my plans are for retiring back to the water in which case I was not looking forward to having to dock every time I wanted to refuel, and go searching out new sources of waste oils. Allows me to produce fuel on board using the scourge of the oceans, plastic.

any way fantastic thread
pardon my enthusiasm and thanks for all the build it information
I'll likely have a few dumb questions but will post pictures soonest

cheers
B

no to go find the notifications settings in this thing
;-)

[Boston]

if you raised the temp slightly from 350° to 400° or so would it break down the long carbon chains into the desired diesel viscosity ?

The process is really simple, it is similar to how alcohol is made. If you heat plastic waste in non oxygen environment, it will melt, but will not burn. After it has melted, it will start to boil and evaporate, you just need to put those vapors through a cooling pipe and when cooled the vapors will condense to a liquid and some of the vapors with shorter hydrocarbon lengths will remain as a gas. The exit of the cooling pipe is then going through a bubbler containing water to capture the last liquid forms of fuel and leave only gas that is then burned. If the cooling of the cooling tube is sufficient, there will be no fuel in the bubbler, but if not, the water will capture all the remaining fuel that will float above the water and can be poured off the water. On the bottom of the cooling tube is a steel reservoir that collects all the liquid and it has a release valve on the bottom so that the liquid fuel can be poured out. Here are some pictures to better understand the design:









This device works on electricity (3 phase), it has six nichrome coils as heating elements and consumes a total of 6kW (1kW each coil). The coils are turned on and off by three solid state relays, one for each phase, the relays are controlled by a digital thermostat with a temperature sensor just a bit below the lid, so that the vapor temperature can be monitored. You need to heat the plastic slowly to about 350 degrees and just wait till it does the magic. Our device has a capacity of 50 liters and can hold about 30 kg of shredded plastic. The process takes about 4 hours, but it can be shortened considerably by tweaking the design a bit. As I said, this makes a liquid fuel that can be used as multifuel, that means it can be used on diesel engines and also on gasoline engines, but we still need to test it will work on gasoline. It works for diesel engines just fine, that has already been tested. There is a difference in what plastic you use, if you use polyethylene (plastic cans, plastic foil, and all kind of flexible non break plastics) you will get out liquid fuel that will solidify as it cools into paraffin, it is still good for diesel engines as long as you use a heated fuel tank, because it needs to be heated just about at 30 degrees celsius to be liquid and transparent. If you don't want that, you can put the paraffin through the device for one more time and you will chop those hydrocarbons even smaller and half of the paraffin will turn to liquid fuel and other half will remain a paraffin, but much denser and will melt at higher temperatures, this is the stuff you can make candles out of and it does not smell at all when burned, maybe a bit like candles. But if you use polypropylene (computer monitor cases, printer cases, other plastics that break easily), you get out only liquid fuel, no paraffin at all. All you need is just filter the fuel out of solids and you good to go and put it in your gas tank. We have made the analysis and it is almost the perfect diesel fraction. It has no acids or alkalines in it, like fuel from tires does. The unit in the pictures can convert about 60 kg of plastic into 60 liters of fuel in one day. Other methods of heating the reactor can be employed, electricity is just easier to work with and control. Some Japanese companies manufacture such devices, but their prices for this size unit is more than 100 000$, our home made device cost us 900$ max. We use aluminum oxide bricks to insulate the heat, they are light as foam and can be easily cut in any shape, but any kind of insulator can be used. The bricks make the highest costs for this device. It can also be made using liquid fuel burners to heat the reactor, this will enable to make the device self sustainable by using about 10-15% of the produced fuel along with the produced gas. A small farm can use a device this size and make fuel for itself by converting plastic waste to fuel, farms have very much plastic waste and it is a big problem, at least in my country. Our next goal is to make the same thing possible using biomass, every farm could then use old leafs, wet grass, saw dust and all kind of biomass and gasify it into tar like substance that can then be put through the pyrolysis device and turned into biodiesel. But we will see about that. Here are some fuel samples:

These are samples from polyethylene, in the first run out comes mostly paraffin like liquid that solidifies at temperatures below 20 degrees celsius, the other clear sample is from the same paraffin that is gone through the process one more time. Will post more pictures and a video later.
Thanks,
Jetijs

[Boston]

I'm on a role

Found a number of used electric kilns for sale ( ~$400 ) by applying the digital controller with the thermocouple you suggested it looks like it would be pretty easy to keep the temps within the optimum range. Looks like this is a pretty low pressure system so the reaction chamber could just be welded up to match the octagonal shape of the kiln chamber. The reaction chamber looks like the expensive part but other than that I'm thinking a used kiln should work pretty well. I might just go with a piece of pipe for the reaction chamber though even if its not as efficient as the custom shape.

hmmmm
still working up a parts list but I'm thinking if I go with the kiln I found and its got a chamber size of 18 x 18 x 22 then thats about 4 cubic feet of space. so call it 3 cubic feet of compressed shredded plastic, it would depend on how compressed the material was but I'm going to guess at 25lb a cubic foot or 75 lbs each run, given that the conversion from a solid to liquid in this case is pretty darn close I'd guess that would leave me with say 65lbs of liquid fuel or about ten gallons of diesel fuel.

hmmm
how do you manage to get 25 gallons ( 100 liters ) out of a propane bottle sized system?

my calculations are probably off somewhere

[mbrownn]

So you had opportunity to see a real professionnal set up ? a petroleum refinery ? heavy oil visbreaking ?

please let me know.

seems to me the cyclone has to be properly sized to the gaz flux

seems hard to achieve... according to the liquid output, estimate the gaseous flux ? then build one and try it with compressed air at the same flux ?

input dust into the input flux to see if it works or not ?

seems a real art work ...



put water to remove oxygen :
it should work, in the plastic set up if have some room under the plastic, but you'll get this water condensed at the output with your diesel

with the oil (wmo) set up I think it's not good : water is heavier than oil, so will go under. and when boiling, it would spill wmo everywhere, contaminating the output with feedstock wmo

What I saw was a long time ago and I didn't really know what it was at the time. Only since reading this thread did I realize exactly what they were.

I wouldn't say they were professional setups because they looked like they were one off designs, back then all this sort of technology was kept very quiet.

I have posted most of what I can remember in this thread so you can go back and read it. probably my biggest contribution to this thread is the info that cyclone type filters were used on them along with feedback loops.

The little that I know about cyclone filters is that they work best at a specific gas flow through them, this may have been one reason for the feedback loops as they could be left open until the desired gas flow was reached.

The diesel is collected at a higher temperature than what water boils so that should not be a problem however the water will condense in the gasoline fraction. luckily gasoline and water are not missable so separation should not be a big problem. A small amount of gasoline or other low temperature petroleum distillate could be used instead of water if water is a concern for you.

[islander]

Thanks, M.Brown

Are you sure about the gasoline would not take % of water in it ?

About oil, I learned that oil molecule has a polar end (likes water) and so one molecule of water can be bond to one (long) molecule of oil.

they say : the way we measure the size on an oil molecule, is to let a small (measured) amount of oil on water and measure the surface it will spoil. all the oil molecules will plug it's polar end in contact of the water under it, so they know the layer is made of 1 oil molecule only, and can make calculations.

So we can have water in oil for one %

and I don't know about gasoline ?

but that I can tell, is water is a terrible ennemy to injectors. I learned it by myself !

I am not speaking about free water. Free water surely damage the injectors by forming and invisible rust that make the functionning unstable.
but until now, I don't know if the water linked in oil can provide corrosion of steel or not.

but according to your ideas, M.Brown, so we should insulate the gasoline/water fraction from the gasoil, dealing with the condenser.

that's right, we always can boil again the gasoline/water content, as controlling the temperature it should be possible to let bonded/and free water appart.

some interesting link :
Recycle Plastics & oil into Diesel,Plastic to Diesel Process,DepolymerizationRecycle Plastics & oil into Diesel,Plastic to Diesel Process,Depolymerization

[mbrownn]

Are you sure about the gasoline would not take % of water in it ?

About oil, I learned that oil molecule has a polar end (likes water) and so one molecule of water can be bond to one (long) molecule of oil.

they say : the way we measure the size on an oil molecule, is to let a small (measured) amount of oil on water and measure the surface it will spoil. all the oil molecules will plug it's polar end in contact of the water under it, so they know the layer is made of 1 oil molecule only, and can make calculations.

So we can have water in oil for one %

and I don't know about gasoline ?

but that I can tell, is water is a terrible ennemy to injectors. I learned it by myself !

I am not speaking about free water. Free water surely damage the injectors by forming and invisible rust that make the functionning unstable.
but until now, I don't know if the water linked in oil can provide corrosion of steel or not.

but according to your ideas, M.Brown, so we should insulate the gasoline/water fraction from the gasoil, dealing with the condenser.

that's right, we always can boil again the gasoline/water content, as controlling the temperature it should be possible to let bonded/and free water appart.

some interesting link :
Recycle Plastics & oil into Diesel,Plastic to Diesel Process,DepolymerizationRecycle Plastics & oil into Diesel,Plastic to Diesel Process,Depolymerization

All I know is I used to sell water removal filters to people that wanted to remove water from oil and diesel, the water is visible as the oil goes cloudy. Gasoline does not go cloudy and simple water traps are sufficient for removing drops of water before use.

Using pyrolysis, if the correct temperature is maintained in each fractionating vessel, water will not be an issue in the diesel output. As water separates easily from gasoline this should not be an issue either but if it is a concern for you then simply use gasoline in the reactor vessel to push out the air.

[islander]

Thanks, M. Brown

Thanks for tour experienced help ! I Will follow your way. Unfortunately, i Am Still on single total condenser instead of fractionnator Like you.

I want to build a fractionnator soon, not so much Info on that stuff. Excepted Some pictures I found on the picture area on this site, but havent already found the related reasults and text about this trial...

[mbrownn]

The fractionater can be separate vessels in series, you just need to hold each vessel at the required temperature to get good quality fuels.

[otpadnoulje]

segnor jetijs

is this waste plastic useable for converting to diesel fuel. I can got it for 10 euros per ton.
Thanks[IMG][/IMG]

[Jetijs]

segnor jetijs

is this waste plastic useable for converting to diesel fuel. I can got it for 10 euros per ton.
Thanks[IMG][/IMG]

Hi.
That is mostly PET and is not usable. So far what we know works for sure is Polyethylene (PE,LDPE,HDPE), polypropylene (PP) and waste motor oil. All these materials consist of hydrogen and carbon and are suitable to make hydrocarbon fuels, PET has extra oxygen in it, this will pose an explosion risk, the output will contain more water and the diesel content will be very small and it will be black, because the oxydation will have already happened in the reaction chamber. Also you will be left with lots and lots of carbon residue.
Jetijs

[Jetijs]

And one more will a hot air gun or hot air blower can be used instead of the burner or coils?

That could work, those hot air guns produce up to 600 degree celsius heat, just make sure the heat is fransfered efectively

o

Master Jetijs wrote :

Might be a great idea to combine the thermal cracking with a plasma gas processor.

do you mean in order not to obtain paraffins or heavy fractions form the plastic ?

I am not sure yet, as far as I know it should just crack the vapors further. My goal would be to crack it till propane and butane and use that to inject directly into engine, should give a major fuel saving as it was discussed earlier. This still needs to be tested. Electric arc plasma pretty much disassembles everything it sees into atomic state and after the influence of plasma is gone, the pieces will try to recombine back together, but only very simple structures will be made, such as hydrogen, metane, propane and butane. If pressures are great, those small building blocks might combine into something more complex like gasoline or even diesel hydrocarbin chains, but that needs very stable conditions.

if you raised the temp slightly from 350° to 400° or so would it break down the long carbon chains into the desired diesel viscosity ?

So far this has not checked out, the thing is that if you rise the temperature a bit, it does not really influence the fuel percentage, it just speeds up the process, at least raising the temperature from 380 to 420 degrees did so, might be that the percentage of fuels also changed but back then we only had one condenser so it was hard to tell.

[oldguy]

Hi Otpadnoulje,

From the pictures you have shown, there is plenty of PE in those bales. Some simple generalizations:
1. Pop bottles are generally PET or #1, however, the pop bottle tops are PE or PP
2. Film is generally PE or PP
3. Lids are generally PE or PP
4. Clear plastic, as you find on cakes or fruits, unless it is very audibly crinkly, discard - they are PVC or PET. The crinkly stuff is PS
4. Tubs are generally PE or PP
5. Chemical bottles, milk bottles, shampoo and cleaner bottles are generally PE
6. If in doubt - for this project - throw it out
Hope this helps in some identification. Sorry Jetijs