How to turn plastic waste into diesel fuel cheaply

[Excalibur]

As a novelty I used the gas in one of these:

[rozier56]

important to note the burner head Excalibur posted! it's a high pressure head burner,not the normal low pressure associated with burners.We use the same ones here.

[wheels]

The only important thing to remember, is that you are playing with mostly Hydrogen Gas and Hydrogen is the most explosive and volatile Gas you can get. But then, any flamable gas is still dangerous, just take precautions. You still need Oxygen to make it Burn, so you have to be absolutely sure you have no oxygen in whatever you store it in. Some have made large PVC bags and stored it that way. You could use it directly as you produce it of course, but if you run an engine, you need to be able to provide enough for the engine to run and if you produce more, then you need to regulate it somehow.
By returning the Gas to the Retort burner, you are basically getting rid of any possible nasty by products that could have come through with the Gas. But you also need to ensure that there is no way that the Gas can "flashback" via the supply pipe into your plant. It can leave a nasty ringing in your ears.

With the design of my plant, we are going to be using the Gas to fuel a completely different process, that at the moment I can not talk about. But I have not gotten to the storage of it part yet. Probably an early next year project.

[Col]

MIG v TIG Welding and longevity of weld seams

Mild steel withstands the heating and cooling cycles far better than most other metals. If the seams have been welded with mild steel electrodes, the welds behave just like the rest of the vessel metal. But if it has been MIG welded, MIG weld is hard low Hydrogen and will present a "different metal"composition at the weld interface. Two different metals, even though they are both steel, can cause a galvanic action with the Acids and heat. So the Welds need to be inspected regularly.

Ok, it has been a long time coming, but in 15mins I am getting the angle grinder out and preparing the bits and pieces I have accumulated for this project. The retort will be made from an air compressor tank. I presume it was MIG welded at time of manufacture (can you tell just by sight?). Going off Wheel's comment above I should grind that MIG weld away and have it re-welded using mild steel electrodes. Has anyone had issues with MIG welded seams?
Thanks.
Excited to be getting into it finally!
Col

[wheels]

Ok, it has been a long time coming, but in 15mins I am getting the angle grinder out and preparing the bits and pieces I have accumulated for this project. The retort will be made from an air compressor tank. I presume it was MIG welded at time of manufacture (can you tell just by sight?). Going off Wheel's comment above I should grind that MIG weld away and have it re-welded using mild steel electrodes. Has anyone had issues with MIG welded seams?
Thanks.
Excited to be getting into it finally!
Col

No you should be fine with a small tank like that. Plus the Air tanks are often made from a slightly higher grade steel than just mild and so much more like the MIG metal it was welded with.
My original comment was referring to a much much bigger Retort. I am using an Air tank and so far there have been no problems and intend to simply change the tank when it gets too worn. It's easy to have a quick look at the tank between uses and make sure everything is OK. Plus I am playing with Plastics that produce a lot of Acids and nasties.

[rozier56]

new changes to plant work well

Recently rebuilt the plant that produced wax problems in the past.
Now have a plant that runs like a DREAM.
Some of the biggest changes are as follows.
1.Firebox wall or pass diameter increased to 40mm all round.
2.Firebox chamber under retort doubled in size.
3.stainless steel deflection plate installed in firebox chamber.
4. increased distillation tower size.
We now able to run the system were the temperature figures from the exhaust system almost match the distillation tower figures.The firebox internal temps are approx. 25*c higher.
No super heating chamber at the firebox which caused high temps and produced the wax.
We have had excellent runs and produce approximately 40lt/hr at 0.84 on hydrometer.Product very clear with the catalyst added.

[jonathan]

pyrolysis

thanks rozier56 for photo keep it up...if you can tell us your tempretures of retort,reflux and condensors...thanks

[Excalibur]

Recently rebuilt the plant that produced wax problems in the past.
Now have a plant that runs like a DREAM.
Some of the biggest changes are as follows.
1.Firebox wall or pass diameter increased to 40mm all round.
2.Firebox chamber under retort doubled in size.
3.stainless steel deflection plate installed in firebox chamber.
4. increased distillation tower size.
We now able to run the system were the temperature figures from the exhaust system almost match the distillation tower figures.The firebox internal temps are approx. 25*c higher.
No super heating chamber at the firebox which caused high temps and produced the wax.
We have had excellent runs and produce approximately 40lt/hr at 0.84 on hydrometer.Product very clear with the catalyst added.

Sounds really good. I'd say you've found the sweet spot where the plant is working in harmony. The way I see it is, the 25°C is the sum of radiated and evaporation heat losses. The .84 reading is excellent and well within usable spec, showing the reflux is working as intended. So, well done. What is the next step, upgrade or refinement?

[sunilkm153]

The only important thing to remember, is that you are playing with mostly Hydrogen Gas and Hydrogen is the most explosive and volatile Gas you can get. But then, any flamable gas is still dangerous, just take precautions. You still need Oxygen to make it Burn, so you have to be absolutely sure you have no oxygen in whatever you store it in. Some have made large PVC bags and stored it that way. You could use it directly as you produce it of course, but if you run an engine, you need to be able to provide enough for the engine to run and if you produce more, then you need to regulate it somehow.
By returning the Gas to the Retort burner, you are basically getting rid of any possible nasty by products that could have come through with the Gas. But you also need to ensure that there is no way that the Gas can "flashback" via the supply pipe into your plant. It can leave a nasty ringing in your ears.

With the design of my plant, we are going to be using the Gas to fuel a completely different process, that at the moment I can not talk about. But I have not gotten to the storage of it part yet. Probably an early next year project.

I am using flame arrestor to prevent flashback. The flame arrestor consist partly of a non-return valve and partly a flame filter that stops and extinguishes any flashback.

[wheels]

I am using flame arrestor to prevent flashback. The flame arrestor consist partly of a non-return valve and partly a flame filter that stops and extinguishes any flashback.

Use with caution. I am not saying it won't work, but I also am thinking that the flame filter inside may clog up and I am not sure what will happen over time with hot Acids. These units are brass and likely to corrode.

[kedigen]

hello to everyone
How is the base oil and natural gas? Does anyone know?

[wheels]

hello to everyone
How is the base oil and natural gas? Does anyone know?

From Plastic??
The Gas is mainly Hydrogen and a little Methane.
The oil or Hydrocarbon liquids will vary depending on what plastic type you are pyrolyzing and are many different types and the exact make up will vary for everyone, depending on how their Plant cracks the Chains. However, PE and PP both create two basic ranges of Hydrocarbons. Which one are you melting? or is it a mixture of both?

[kedigen]

sorry...
How to make base oil and gasoline from natural gas?

[wheels]

sorry...
How to make base oil and gasoline from natural gas?

It's via a very complex and difficult process and in a basic reply, if you don't know, you won't be able to do it and if you do know, then you wouldn't be asking
To expand on that, what I mean is that you would need a really major solid knowledge of Hydrocarbon Chemistry. It requires a specialized process and specialized catalyst. Basically you are taking short Methane and Hydrogen and firstly making Syn Gas. Then you take the Syn Gas chains and join them to make long Hydrocarbon chains. Once that has been done, the long chains then go back through a Fractionating process to be made into the specific hydrocarbons wanted. This process originally took about 40yrs to crack and there are 3500 individual patents covering each step of the entire process. So that tells you how complicated the process is. Yet even though it is complex, it is still done because very pure Hydrocarbon chains are created and they use these a a Base stock for making Synthetic Oils. Hence why good synthetic Oil is expensive.

[mehmetcanural]

Wonderful thread.

Hi all,

This is a wonderful thread.
Thanks Jetijs and all others who contributed.
I have been studying from the very beginning.

Thanks,
MehmetCan