How to turn plastic waste into diesel fuel cheaply

[Excalibur]

Anyway where is best to fit the K type thermo couple for the reflux

I vote for: at or near the top.

[lowriderzzz]

I vote for: at or near the top.

thank you ....

[rozier56]

Hi to everyone,pls can somebody advise me at what temp the holding vessel for diesel should be after i have cracked at 360-380deg C.I am using waste motor oil as feed stock.Retort held at 380*c and temp at top of reflux column 360*c,then going to collection tank(DIESEL), this is where i need to know what temp required to ensure diesel phase.

[Excalibur]

Hi to everyone,pls can somebody advise me at what temp the holding vessel for diesel should be after i have cracked at 360-380deg C.I am using waste motor oil as feed stock.Retort held at 380*c and temp at top of reflux column 360*c,then going to collection tank(DIESEL), this is where i need to know what temp required to ensure diesel phase.

This is an excellent question and I've been pondering over the answer to it as well. To be clear, you'll be wanting to keep the diesel at heat to drive the more volatile fractions downstream. In this way the diesel will gain stability with regard to its' boiling point for use in a diesel engine.

Wiki says diesel:
Contains hydrocarbons having a boiling point in the range of 180–360°C (360–680°F).
Is a mixture of carbon chains that typically contain between 8 and 21 carbon atoms per molecule

Looking at this says that diesel is itself a mixture of fractions, the most volatile of which starts to boil at 180*C. Therefore 170*C would be the upper most temperature I would consider however good results might be had with temperatures much lower. I think the sweet spot will fall into the 100- 175*C range.
I would use the lowest temperature that gives satisfactory results. One gauge of performance is how well a hot engine will restart after being left to sit for half an hour. The more volatile the fractions the fuel has, the more the difficulty. The reason is that the light fraction component boils and bubbles form in the fuel system.

[rozier56]

Thank you Excalibur,great response,will try the suggested temp range and give feed back when i can.

[Beyond Biodiesel]

I understand your concern, but I tried to imitate imakebiodiesel design from THIS video with what i have around.

imakebiodiesel did more than just about anyone on this thread did on this project; however, his condenser section was always weak, so I would not repeat the flaws in others work just because they are the OP, or contributed a lot to this thread.

Anyway where is best to fit the K type thermo couple for the reflux, since i have only one for now for it and the other will go for the boiler. Eventually will buy more for the condenser when I move on to building my bigger unit. (this one is experimental only)

I installed a T at the top of each of my condensers. The TC goes straight through the cross bar and into the vapor stream in each condenser. The vapor stream has to take the turn of the T.

Hi to everyone,pls can somebody advise me at what temp the holding vessel for diesel should be after i have cracked at 360-380deg C.I am using waste motor oil as feed stock.Retort held at 380*c and temp at top of reflux column 360*c,then going to collection tank(DIESEL), this is where i need to know what temp required to ensure diesel phase.

In my experience I get diesel in the 100c condenser trap, but I still get significant amounts of kerosene at about 25c and gasoline at about 0c.

As a fuel blender for almost 7 years I have found that I can make an artificial diesel that runs just fine on a diesel engine by blending light fractions, such as: gasoline and kerosene, with motor oil and vegetable oil; so do not throw away your light fractions, because you can use them as well to make diesel.

[jonathan]

thanks so much beyond biodisiel for help you are giving to other l hope others upload photos of there system and results l will upload mine too but right know l am so busy l have to do a bubbler and try my system thanks everyone in this forum

[Beyond Biodiesel]

You are welcome jonathan.

[sunilkm153]

lid design

Thanks Mike and Romo
The reactor chamber is made out of an old 50 liter steel propane tank, we cut the upper part open and welded on an assembly so that the lid can be bolted on. The flat ring on that the lid is bolted on has a conical groove in it and the lid has an apropriate wedge machined on that matches that groove. The conical shape of these things elliminates the need of a seal, you just bolt the lid on and it will be airtight. I attached a drawing of the lid assembly.

HI, Jetijs
My question is about circular groove made in top lid and flange If instead of conical groove (45 degree) if a rectangular (90 degree)or square groove is made what may the difference in performance of lid and flange is there any type of leakage or any thing else
thanks in advance

[Beyond Biodiesel]

HI, Jetijs
My question is about circular groove made in top lid and flange If instead of conical groove (45 degree) if a rectangular (90 degree)or square groove is made what may the difference in performance of lid and flange is there any type of leakage or any thing else
thanks in advance

We have discussed this issue numerous times in the past. While Jetijs is the OP for this thread, and deserves considerable respect for the courage to be one of the first DIY backyard pyrolysis techs, and posting a thread on it; nonetheless, he does not walk on water, his design was functional, had some good ideas, but could be improved upon, and many of us have done so. He also has not posted here anywhere near as much as others, so my guess is he has only run his unit a few times.

So, I happen to believe that reinventing the seal is unwise. Either purchase a standard flange pair, or fabricate them to spec. They have been tried and true for about 100 years; and you will be able to purchase standard seals that are designed for pyrolysis for just a few dollars.

[fibuslitero]

Hi:
I found this setup for WMO:
https://www.youtube.com/watch?v=KxgHX0wTYzE

I also found this "diesel polishing" system.
Seems interesting for our experimental fuels since I think it is no always possible to avoid finding particles, water and sludge from oxidation in our experimental production:
https://www.youtube.com/watch?v=SKkTM1jwp8I

[engrmalik]

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

Hey Jetjis amazing show of dedication and innovation you put up there ....
Just for a better understanding can you upload any video in which you are using this Plastic waste converted fuel into a Diesel Engine.

[Beyond Biodiesel]

Hi:
I found this setup for WMO:
https://www.youtube.com/watch?v=KxgHX0wTYzE

Thanks for the links, fibuslitero. It looks like that WMO distillation system will process about a quart (L) of WMO in a day. My WMO distillation system will process 5 gallons (20L) of WMO in 4 hours. Here is a link to my work building a WMO distillation unit.
Batch Process Distilling WMO

I also found this "diesel polishing" system.
Seems interesting for our experimental fuels since I think it is no always possible to avoid finding particles, water and sludge from oxidation in our experimental production:
https://www.youtube.com/watch?v=SKkTM1jwp8I

I agree. I find a lot of odd particles that make it through my WMO distillation system. Here is a link to my fuel polishing system, which can process fuel at the rate of about 1 gallon per minute, or faster.
A tour of a waste oil diesel fuel blending system
Welcome engrmalik. There are lots of videos and links on plastic pyrolysis.

[rozier56]

SUCCESS!!! I made my first 20lt of diesel today.pure gold in colour and runs in the car perfectly.This is after reading 1000 plus threads and in between the line's.Perserverance will make you a winner.
Note! no catalyst used yet, will try in future batches.Raw material used was LDPE black irrigation pipe.
Will keep post ongoing as we progress.

[Col]

First working batch

WOOHOOOOO!
Way to go rozier56. Cheering for you.