How to turn plastic waste into diesel fuel cheaply

[boywonder]

Jetijs do you think using engine exhaust gas as a heat source for the propane/reactor tank would work? By placing the reactor into a larger tank that has exhaust gas passed through it...

[mbrownn]

that is not air, those bubbles are formed by overheated plastic which forms gasses and vapors.

I stand corrected

[mina]

This is great work and will help not only to eleminate plastic waste, but it will also cut down on the cost of vehicle fuel. A burner powered by its own fuel will be the greatest improvement as the cost of running the system will only be that of plastic waste.

I was just wondering why you did not burn off the waste gasses in a burner underneath the main reactor chamber so you could harvest some of the BTUs?

Also, are normal drinking water bottles and 2 liter Pepsi bottles useable?

[Jetijs]

Jetijs do you think using engine exhaust gas as a heat source for the propane/reactor tank would work? By placing the reactor into a larger tank that has exhaust gas passed through it...

This should be doable, exhaust gasses have more than enough heat to do this, it is just a technical issue and I haven't thought about that much.

[Jetijs]

I was just wondering why you did not burn off the waste gasses in a burner underneath the main reactor chamber so you could harvest some of the BTUs?

Also, are normal drinking water bottles and 2 liter Pepsi bottles useable?

The current setup is heated with electricity, there are resistance wire coils imbeded in white aluminum oxide bricks around the reactor. There is no easy way to put the flame there also, it would just mess everything up. You need a different design for that.

[hurkatm]

Self sustained Pyrolysis design.

Dear Friends
It will be of great use if we could use flue gases to heat reactor chamber and produce Diesel.
I have designed the simple sketch, I am planning to implement it.
Hope so this should work.
Please comment if there is any fault.

[otpadnoulje]

Dear Jetijs!

I have a problem. I would like to make diesel set up. What will be better? Waste oil to diesel or , waste plastic to diesel. I have seen this machine. YouTube - Homemade Diesel

What is your expirience with black oil?

Please , help me !

Thanks!

[Jetijs]

It is easier and faster to use waste motor oil to get diesel. The process is the same, the temperatures also, but it is way faster and more efficient than whem plastics are used as source. So it all depends on what resources you have available, but then again, the setup is the same, no mater what your source is.

[hurkatm]

Hi minoly

Have a look at this page:
Directory: Blest Machine recycles plastic back into oil - PESWiki
It is about Japanese commercial devices. But those cost so much that almost no one considers using this tech at home. Japanese put all kind of LCD's, sophisticated power management systems and monitoring devices in their units that really does nothing except increase the price. This is easy, cheap and almost anyone can build one without taking out a second mortgage on his house The way we do this is not the only way nor the best, after you know the process, there is lots and lots of room for improvements.

You could build a small table top device for around 300-500$ maybe even less. But I wouldn't use a pressure cooker as they have a heat resistant rubber seal around the lid, it is good for food cooking temperatures, but wont hold 400 degrees celsius, it will melt and leak. Also you need a custom heating element, because ordinary heating coils that are used in water boilers, tea pots or electric stoves wont last long, because of their thin resistance wire. You need nichrome or kanthal resistance wire with diameter around 1.5mm, this will do well. The seal between the reactor and the lid is very important, it must be hermetic and heat resistant, we have tried many ways before and no seal material lasted long, all eventually fail and let the hot plastic vapor seep out, this is not acceptable. We tried heat resistant silicon for use on chimneys and other commercial stuff, not good enough. Eventually we found that the thing that works best is conical groove and a wedge that fits inside that groove around the lid, like you can see in the CAD drawing. When the lid is bolted to the reactor chamber, the fit is airtight and hermetical. The pressures in the system are very low, only such to be sufficient to bubble through the bubbler, this makes it very much safer than commercial flash pyrolysis devices that are also very expensive and affordable only by large companies.

In our case the bubbler at the end is just as a flashback arrester that prevents fire going into the reactor, but the gas really burns so slow, that it is not really needed, but better to leave it in, safety is never too much. Also the bubbler can be used to eliminate the need of condensing tanks, because the vapors cool sufficiently when bubbling through the water to turn into liquid fuel, that can the be poured off as it does not dissolve in water but floats above it. The produced gas should be burned or vented outside.

Dear Jetijs
First of all I would like to thank you for sharing this great thecnical know how of making diesel from waste plastic.
I hop you have gone through my previous post to make this self sufficient unit.
I have small doubt, you said you tried withh all kinds of sealing materials but the performance was not as desired and finally you made a "V" shape grove for sealing. I want to know what is the depth of grove and any kind of sealing material is also used with grove.
Once again thanks for your efforts and help.

[dutchdivco]

Gee, Jetsis

I'm so grateful to you for sharing this information! Now, I'm too lazy to read back thru the old posts, on this thread, so I want YOU to take time away from working on this project, to answer my questions, which I could easily find the answers to, simply by reading thru the earlier posts.

Sorry if this seems a little harsh, but this is the umpteenth time we have seen posts like this, and its getting really OLD!Jim

[hurkatm]

Leakage

Dear Jetijs,
Please reply to my earlier mail.
Also I Need your guidence to make one reactor. Please can you post the actual dimensions of your project. as what ever literature I have read till now on Pyrolysis conclude that Temperature and Residance Time are two inportant factor which decide tha Quality and Quantity of Diesel and other products that are produced.
Also I have a doubt that What will happen if there is a leakage and Air/Oxygen enters inside the the Reactor at say peak period i.e. at about 400 deg. will it turn into explosion (Fire) as flamable gases will get oxygen or just that batch will be failed and plastic will turn into solid lump.
Thanks in advance for your quick reply.

[islander]

hello Jetijs

I am on the waste motor oil set up. I discovered cracking by myself : I was trying to distillate some motor oil from my diesel VW, And I got a fraction of gasoline ???? So I did dig a lot in the net for years...

Now I am on my second set up, And I've got a problem : this set up only produce gaz. yes, I get gaz like methane etc, from waste motor oil.

I even don't get a drop of liquid. Gaz, gaz, plenty of it.

Maybe I could partly condense it into a liquid, should not be so difficult.

It was not my intention, As my need is producing clean diesel for my car.


my set up is like this :


better start by the end to explain:
at the end of the chain, is a gaz injector into the furnace. the gaz comes from a refrigerator motor output, that sucks on the input vacuum in a liquid recovery tank for diesel (or product done). the input of recovery tank is linked after 10 meter long pipe, to the gaseous output of the reactor vessel.

the distance is for safety, also the pipe is buried in earth, so it's discreet, can cool the exess heat, and gives me a chance in case of fire/explosion issue.

the reactor is a very small tank (about 7 liter) made of steel, but very well insulated, heated by a burner under it.

The input of waste oil is done using an aircond electric valve, actuated by a timer : opening the valve into the cracking vessel sucks the waste oil in.

I tried 2 temperatures : 300°C and 700°C

at 300°C I first have a little something coming out, but soon depleted. So impossible to use.

370°C not tried (malfunction in level device) but looks like cracking starts at 400 and over, higher temp the quicker.

at 700°C the pyrolisis cracking works very well, but my set up makes only gaz. real gaz, not vapours from a liquid.


I read somewhere "the quicker the cracking is done, the less carbon deposit, that's why thermolysis systems use about 700°C, to get quick job done and less deposit"

on the other hand I read "waste motor oil cracking has to be done without any catalyst (that would be quicky poisonned anyway) but at a low temperature, about 370°C, this way avoid any carbon deposit (coking)


this gaz problem looks very strange to me ! my former set up was smaller volume about 2.5liter and almost not insulated (on the same furnace) it worked better when getting red hot (nearly 650-700°C)
it produced a kind of black dirty diesel.

what it the difference between the 2 ?

insulation on top cracking vessel (before haven't)
and heated volume (this one way bigger)

I had the idea probably hydrocarbons in vapours state in the vessel will continue to decompose into gases; the longuer they are exposed to the high temperatures, the more chances they have to be broken down into smaller molecules, the smaller ones are the gazes.

yesterday I did cut a part of my reactor. And now I still have a lot of gaz, but I also get a little of gasoline.

coke production is a problem in a set up like this. that is the reason I wanted to have more room inside the cracking vessel.

I can't fill a lot the cracking vessel when it is hot at 700°C temp : output production (actually in terms of gaseous form) would be enormous.

I'll try to post picture later.

I am happy with my vacuum system, when starting the fire, I also start the vaccum pump. The residual gaz, is then burned and let the pot get hot quicker, in the meantime, it lets me check if my system have some leak (vacuum meter would not go down) and it also removes the risk from explosion of cracking vessel.

explosion of cracking vessel was the first of my thoughts, as heating air+gaz vapours at the temp of ignition (600 and up) are the condition of use of a diesel motor (heat+air+gaz = boom)

it is only a matter of chance if it don't happen (air+vapour mix have to match the combustion ratio at the kboom temp) so I don't want to try it.

[islander]

patent about converting waste motor oil into diesel

low temp process without catalyst

Process for converting waste motor oil to diesel fuel - US Patent 5885444 Description


(hard to read for me, I'm not english native language) it seems to me the reason they have no coke in reactor is they don't completely crack the waste oil ?

[otpadnoulje]

Islander, your working temperature is tooooo heigh. It should be under 400c.

As higher temperature as much coke and more uncondensable gaz. The best way is 360 - 370 c.

After all you will need additive.

[islander]

yes I think you are right.

but it is also dependent of the shape of the reactor. Because yesterday, even at 400 °C only gases, even lower temp. The only change was the quantity of gaz.

Today evening I changed something, remove some insulation on top of the reactor/boiler.

And I got liquid !

not enough, only 2 liters after 2 hours of operation.

I did use the temp between 380° and 450°C

But I got a problem, as it was not possible to dry out the remaining oil in the reactor. It stopped produce liquid and started to produce more gases at 450°C.

even if I was distilling with a vacuum quite good (maybe 1/2 atmosphere)

It was easy to dry it, just let the temp go over but I would get only gaz, to my belief.

I think my set up don't work as it should.


how to make it not give me this carbon dust inside, how to produce more, how to crack all, or nearly all the WMO...


What kind of additive do you speak of ? Is it the additive against oxydation, it was related in some post here ?


Does anyone understand something on this set up ??
YouTube - Homemade Diesel

I found very interesting information, seems very related to waste oil cracking.
http://www.coking.com/DECOKTUT.pdf

it seems very needed to use a coker, my first set up was foul of coke after little production ?

Islander, your working temperature is tooooo heigh. It should be under 400c.

As higher temperature as much coke and more uncondensable gaz. The best way is 360 - 370 c.

After all you will need additive.