How to turn plastic waste into diesel fuel cheaply

[Marso Green]

why is everyone trying to cool the gasses in condensors prior to entering the collection tanks, I intend to plumb the gas feed directly to the bottom of the collection tanks, then plumb the condensed fluid to a thermostatically controlled hydraulic cooler. I will have to always start the process with fluid in the tanks, but it will be much easier and more efficient to controll the temperature of the fluid that the gas will bubble through than to controll the temp of the gases directly. ultimately this is how a fractionating column works. they allow the gasses to bubble through fluid that is of the desired temperature, the desired fraction will then condense and remain with the fluid in that fraction. Is there any flaw in my thinking?

On an other matter, this unit shown will be both batch and continous feed, I Intend to run it while I work in the welding shop during the day. It will start out with a batch of plastic, that I intend to melt into wmo in the beginning, ( 20 L plastic pails that the oil comes in ) left over solvent and paint, and a bit of rubber from our scrap tires, then I intend to have an oil feed preheated by a coil in the exhast pipe, that will drip wmo and crude oil into the retort so that It may operate uninterupted for 8 to 10 hrs at a time. But I have a small problem, I have no Idea how to monitor the ammount of fluid in the retort after it is sealed up, I considered setting the unit up on a scale so that I may read the weight and adjust feed rate accordingly, anybody have any other suggestions?

Regarding gas bubbling through thermally controlled fluid, I like the idea, but what fluid would you use? The actual fractions you're looking to output? Should they be mixed with something else to allow slightly higher temperatures without risking the original fluid to evaporate? Also I'm not clear on the statement that this is how the fractioning column works. I was under the impression that a reboiler heats the bottom of the fractioning column and the temperatures are consistent with elevations, and trays are strategically placed at the desired temepratures for condensate. If that is not correct, could you please explain your theory?

As for the fluid level in your system, have you considered furnace sight glass? I recall seeing some that are rated well above any of the temperatures of interest to us

Regards,

Marso Green

[Beyond Biodiesel]

Sorry, i intend to pack each section, what i am not sure on is should there be seperate catalyst in each section also?

Cat cracking only happens efficiently at elevated temperatures of 800F (425c). There is no reason to go above that temp for cracking to take place. And, no reason to mess with catalyst under that temp.

By the way, I forgot to mention that most of the coke in the retort is not carbon, but ash. Ash is dissolved salts, which is mostly silica. So, once the retort has been regenerated (carbon burned off) by admitting air, or O2, when it is at 800F (425c), then there is going to be a lot of ash at the bottom of the retort.

If you have a large ball valve at the bottom of your retort, once the retort has cooled, then you could pressurize it to 15 PSI (1bar) with compressed air, then open the drain valve. That should blow out most of the ash. If not, then try it again.

[thissideup]

Regarding gas bubbling through thermally controlled fluid, I like the idea, but what fluid would you use? The actual fractions you're looking to output? Should they be mixed with something else to allow slightly higher temperatures without risking the original fluid to evaporate? Also I'm not clear on the statement that this is how the fractioning column works. I was under the impression that a reboiler heats the bottom of the fractioning column and the temperatures are consistent with elevations, and trays are strategically placed at the desired temepratures for condensate. If that is not correct, could you please explain your theory?

As for the fluid level in your system, have you considered furnace sight glass? I recall seeing some that are rated well above any of the temperatures of interest to us

Regards,

Marso Green

I simply plan to start the process for the first time with diesel / kerosine in the first collection tank and gasoline in the second, I will not be separating out the kerosine. Then that fluid will circulate to a cooler then return to the collection tank. It could not be mixed with anything else as that would then contaminate the end product but I see no reason to as by cooling the produced fluid to the desired temp then the only fluid that would evaporate are the lighter fractions which we would want to evaporate and move to the gasoline fraction anyhow. As for the sight glass, I'm pretty certain that the conditions inside the reactor would deposit a layer of carbon over the glass making it useless in short order.
In my understanding the trays are strategically placed in the column so as to cool naturally to the appropriate temperature, but these trays also hold a layer of condensed fluid with bubble caps that the up rising gas must bubble through in order to make its way up through the column. These trays then are plumbed to a collection system for that fraction. I simply will be replacing a column with my tanks that will be cooled mechanically to the desired temp as trying to design a column that would operate at the desired temp would be an engineering nightmare for someone with a grade 10 education. My tanks will however have packing similar to what others are putting in their condensors so as the break apart the gas bubbles and allow more of it to come into contact with the fluid the same way the foam on the end of the air hose in a fish tank breaks the bubbles down and adds air to the water more efficiently.

[Marso Green]

fluid level

As for the sight glass, I'm pretty certain that the conditions inside the reactor would deposit a layer of carbon over the glass making it useless in short order.
.

Perhaps the level can be monitored indirectly through viewing glass in the condensers, not the reactor, where no carbon deposit will take place.

Alternatively, and if it's simpler to only monitor the reactor level, how about a float mechanism or level indicator with extension to the outside and temp rated ball joint seal? I wonder, however, if joint friction would be too high to make this approach viable


Just thinking out loud.

Marso Green

[dutchdivco]

Not sure I'm following you, but

How about this; You have "X" amount of fluid, that the gas 'bubbles thru', and this fliud is 'cooled' to the right temp,so that the fractions you want condense, while 'lighter' fractions reamain a gas and go on to the next section.
O.k., so when this 'new' material then 'adds to' the amount, so that its "X+", the level rises; simply have a 'drain' at this level, that would allow the 'extra' amount to run off to your collection tank?

Seems like with 'trial and error' you could set this 'drain' at the right 'height' so that when the circulating fluid was circulating, it would be 'just below' this drain, and therefore any material that condenced, and 'added to' this level, would run out the drain, yes? Granted, heat causes expansion, but this may be able to be 'allowed for', and this system may not need to be THAT exact.

Perhaps, after each run you would need to add a little fluid, to get your 'cooling fluid' to just the right level, to start things up? Jim

[thissideup]

How about this; You have "X" amount of fluid, that the gas 'bubbles thru', and this fliud is 'cooled' to the right temp,so that the fractions you want condense, while 'lighter' fractions reamain a gas and go on to the next section.
O.k., so when this 'new' material then 'adds to' the amount, so that its "X+", the level rises; simply have a 'drain' at this level, that would allow the 'extra' amount to run off to your collection tank?

Seems like with 'trial and error' you could set this 'drain' at the right 'height' so that when the circulating fluid was circulating, it would be 'just below' this drain, and therefore any material that condenced, and 'added to' this level, would run out the drain, yes? Granted, heat causes expansion, but this may be able to be 'allowed for', and this system may not need to be THAT exact.

Perhaps, after each run you would need to add a little fluid, to get your 'cooling fluid' to just the right level, to start things up? Jim

Pretty much the Idea, though I may install a level switch and electric fuel pump to pump the fluid from the collection tank to a 45 gallon drum when it reaches a certain level. I want to automate as much of the process as possible.

[Excalibur]

By the way, I forgot to mention that most of the coke in the retort is not carbon, but ash. Ash is dissolved salts, which is mostly silica. So, once the retort has been regenerated (carbon burned off) by admitting air, or O2, when it is at 800F (425c), then there is going to be a lot of ash at the bottom of the retort.

If you have a large ball valve at the bottom of your retort, once the retort has cooled, then you could pressurize it to 15 PSI (1bar) with compressed air, then open the drain valve. That should blow out most of the ash. If not, then try it again.

That is a most interesting and intriguing idea. Thanks for bringing it up.
Thinking in terms of total safety, when is it reasonable to commense the admittance of air. Logically I think that if the gas flow has stopped, then you wait 10mins more, is that being over cautious?
The large ballvalve you mention. This would no doubt need to be able to handle the 425C as it would be in contact with the retort heated feedstock. My memory says that high heat ballvalves are all metal construction with no plastic or rubber parts. Perhaps something along the lines of a steam valve?

[Beyond Biodiesel]

That is a most interesting and intriguing idea. Thanks for bringing it up.
Thinking in terms of total safety, when is it reasonable to commense the admittance of air. Logically I think that if the gas flow has stopped, then you wait 10mins more, is that being over cautious?

Once you are at your terminal temperature, then, after some time, you should find the exit flow nearly zero. This could be 15 minutes to hours for the exit gasses to drop that low. What you do not want to happen is admit air when there is still volatiles waiting to be evaporated Boom, ooh!

Also, once air, or O2 is admitted to your retort, then the temperature should rise to 1200F (650c) This is normal and expected for the regeneration cycle because C burns naturally at 1200F (650c). You may even need to raise the temp to that level before you begin your regeneration cycle.

The large ballvalve you mention. This would no doubt need to be able to handle the 425C as it would be in contact with the retort heated feedstock. My memory says that high heat ballvalves are all metal construction with no plastic or rubber parts. Perhaps something along the lines of a steam valve?

Ball valves are typically sealed with teflon, so they are good to 500F (260C). The way to keep from ruining a valve on a retort that goes higher than that, is to pipe the valve outside of the insulation far enough to a point that does not get hotter than 500F (260C). It would also be advisable to wait for the retort to drop below 500F (260C) before pressuring it to 15PSI (1bar) to blow out the ash. I would wait until it was near ambient temps.

Also, depending upon how big your retort is you will want that ball valve relatively large. Say a 55 gallon (200L) retort could use a 1" (2.54cm) ball valve. Larger than that would want a 2" (5cm) ball valve.

By the way, plastic cracking is not the only thing that one can extract fuel from with a retort and condensers. Terpenes can be extracted from any wood residues from the lumber industry. There are also some plant sources of terpenes that are even more abundant producers of terpenes. For instance, citrus rinds and seeds have an abundance of terpenes. Some trees drip terpenes, such as: acacias, cedars, eucalyptus, and tamarisk.

I am surprised that Jetijs, lives in a forest, in a country with lots of forest, and runs his retort near a lumber mill, but does not get free sawdust from that lumber mill to extract the Terpenes from to make his fuel. Instead he is buying bailed plastics. He is like a man in a boat surrounded by water, but he can’t find any water to drink.

[Asad Farooqui]

Bio-mass pyrolysis

[QUOTE= I am surprised that Jetijs, lives in a forest, in a country with lots of forest, and runs his retort near a lumber mill, but does not get free sawdust from that lumber mill to extract the Terpenes from to make his fuel. Instead he is buying bailed plastics. He is like a man in a boat surrounded by water, but he can’t find any water to drink.[/QUOTE]

Hello ;
Extracting Turpenes from sawdust .....
Have you done it yourself ???
If yes than you have done a wonderful Job .
Like to share your experience ???

If you haven't experimented yet ;
Than I think so you are trying to say about waste Bio-mass pyrolysis to OIL ...
What I know that Not only sawdust, waste lumber-wood but other waste Bio-masses like Corncobs, rice hush, grape seeds, wheat waste, sugar-cane waste etc etc can be pyrolysed into crude oil .
But this Oil is very thick/black & cannot be used directly as diesel/kerosene oil.

[Excalibur]

Once you are at your terminal temperature, then, after some time, you should find the exit flow nearly zero. This could be 15 minutes to hours for the exit gasses to drop that low. What you do not want to happen is admit air when there is still volatiles waiting to be evaporated Boom, ooh!

Also, once air, or O2 is admitted to your retort, then the temperature should rise to 1200F (650c) This is normal and expected for the regeneration cycle because C burns naturally at 1200F (650c). You may even need to raise the temp to that level before you begin your regeneration cycle.

Ball valves are typically sealed with teflon, so they are good to 500F (260C). The way to keep from ruining a valve on a retort that goes higher than that, is to pipe the valve outside of the insulation far enough to a point that does not get hotter than 500F (260C). It would also be advisable to wait for the retort to drop below 500F (260C) before pressuring it to 15PSI (1bar) to blow out the ash. I would wait until it was near ambient temps.

Also, depending upon how big your retort is you will want that ball valve relatively large. Say a 55 gallon (200L) retort could use a 1" (2.54cm) ball valve. Larger than that would want a 2" (5cm) ball valve.

Thanks for the great comments
I've been giving some thought to the ball valve and the positioning in the retort. If it's placed on the retort floor but far enough away so as not to overheat, it would create a pocket of feedstock that would also be the last to evaporate once the cycle concludes.
Placing it on the retort wall at the lowest point possible could allow the melted feedstock to run back toward the reactor, especially if the pipe leading away had the valve end slightly elevated.
Another thought is to make my own valve from steel, employing a tapered seat. This way the valve could be anywhere on the wall or floor.

I ran a small test using 3 liters of oil 50/50 hydraulic & engine oil in a small vessel fired by a kero stove. In this trial I wanted to see what the lowest temperature the thermal cracking would work at. So following your suggestion earlier that maybe 260C could be enough, I gradually brought the heat up. Two hours after starting, the temp was 300C and here was the first faint signs of gas. I abandoned the test here but it appears that sub-300C temps are too low in this instance.
The question arose: is the temps required to crack say a 30W oil less than temps required to crack a 90W oil as feedstocks? I'm reasoning that the boiling points are different for the two fluids but are these relevant to cracking levels? Or am I completely wrong with the theory?
Thanks

[Uncorruptable]

Once you are at your terminal temperature, then, after some time, you should find the exit flow nearly zero. This could be 15 minutes to hours for the exit gasses to drop that low. What you do not want to happen is admit air when there is still volatiles waiting to be evaporated Boom, ooh!

Are we referring to a continous feed build here? As the bubbler would notify you to any reverse action of air drawing back into the reactor, no?

I am surprised that Jetijs, lives in a forest, in a country with lots of forest, and runs his retort near a lumber mill, but does not get free sawdust from that lumber mill to extract the Terpenes from to make his fuel. Instead he is buying bailed plastics. He is like a man in a boat surrounded by water, but he can’t find any water to drink.

Hmm, would sheets of chipboard be of any use for this?

It contains quite a few other chemicals in the form of resins & waxes etc but i can lay my hands on literally tons of this on a very regular basis?

[Asad Farooqui]

chipboard

chipboard[/URL] be of any use for this?
It contains quite a few other chemicals in the form of resins & waxes etc but i can lay my hands on literally tons of this on a very regular basis?

Hello ;
Chipboard contains Urea Formaldehyde (UF) resin as a binder.
Pyrolysing chipboard means effects of UF has to be considered . How Uf can effect the pyrolysed oil properties ???

Most importantly, Do you know how to pyrolyse Bio-Mass ???

All around the world experts mainly focus on pyrolysisng PE & PP type plastics.
So for small scale units this is the Best Bet .


Lastly I would like to request ;
We should only suggest anything on the Forum, Untill we have tried it ourself.

Lots of people go through this forum & they believe that as it is written at the forum, than definitely its true .
People like Jetijs I see, there experiments speak more than he himself .

I can give you a list of 50 different Bio-masses & Marine wastes like Algea which could be pyrolysied to oils .
Research is going on to make car-fuel oil like diesel,kerosene,gasoline, pestisides , chemicals & solvents .
But it requires very expensive High tech machines .

Please keep things simple don't complicate them .

[Uncorruptable]

Please keep things simple don't complicate them .

Hi Asad,

I guess that is a no as the short answer, would this material be attractive to anyone do you think? As i said, i can access large quantitys of chipboard material that goes to rechipping.

P.S.

Very good point regarding discussion v's actual tried & tested.

[Excalibur]

Are we referring to a continous feed build here? As the bubbler would notify you to any reverse action of air drawing back into the reactor, no?

Hi Uncorruptable
No. Continuous feed or bubblers aren't mentioned in the current discussion you refer to. For the full picture, please re-read from post 1505.
It's about cleaning the retort without dismantling, a sort of "Clean-In-Place" approach.

[Uncorruptable]

Hi Uncorruptable
No. Continuous feed or bubblers aren't mentioned in the current discussion you refer to. For the full picture, please re-read from post 1505.
It's about cleaning the retort without dismantling, a sort of "Clean-In-Place" approach.

Ahh i see, i will be happy just to proceed with a batch system that i have to clean myself at the end of the process for now, you have to learn to walk before you can run as the saying goes.

Having consulted my electrician he has confirmed that i can use an old electric cooker for the purpose of heating, he has told me (as jetijs did way back on page 1) how to measure the output and wire needed via resistance from multimeter to replace the elements on the cooker, i will then use the controls from the oven, grill & one of the top rings to increase the heating power to the reactor. The combined power acheived will be 6 Kw from the three coils.

I have sourced materials for reflux column & will begin construction of that this weekend.

Fire bricks rated to 1500'c at €2.35 each, quite thin so i will have to work out how i am going to suspend the electric coils as i dont think i could afford to cut into the bricks, i want to be able to retain aas much 'wall' as possible to keep heat in, any ideas?