How to turn plastic waste into diesel fuel cheaply

[fox32]

Greetings guys, merry christmas!

Good day to everybody, and let me tell, you guys, are something rare, doing such an amazing job, and taking the time to teach the rest of us! I'm new to the site, i just found it through the ol' google, searching for plastic to diesel, and for the last day, and past hours i have read until page 54 and now my eyes are like onions and, my neck veins are bulging like Luca Brasi when he-s whacked in Godfather. I have learned a great deal of valuable informatiom, but still i can't seem to figure out some things. So...here it goes.

1- The reflux chamber. How does it looks on the inside, where does it sits, at what temp(in the early posts jetys recomended a lower temp, at the las page Beyond Bio, recomended top temp) this is my biggest unknown.

2- The catalist chamber. It is inside the reflux, after or before?

3- Should the first condenser be before the cooling tank or after it?

4- would grapitated azbest rope/simple azbest rope be a good substituent for a seal? Maybe for replacing teflon tape in threads?

And last one, Beyond Biodiesel, and Excalibur, from what i have read you have some nice setups, also Jetys but he wasn't on the forum for a while -you may have done this already- but could you post some schematics, plans, photos, anything that can be a source of inspiration on the forum? That will be highly apreciated!


Thanks alot guys, i wish you a Merry Christmas and all the best!

Florin

Edit* Forgot to mention, i'm only using plastic, and i want to get as much diesel as possible.

[Beyond Biodiesel]

Good day to everybody, and let me tell, you guys, are something rare, doing such an amazing job, and taking the time to teach the rest of us! I'm new to the site, i just found it through the ol' google, searching for plastic to diesel, and for the last day, and past hours i have read until page 54 and now my eyes are like onions and, my neck veins are bulging like Luca Brasi when he-s whacked in Godfather. I have learned a great deal of valuable informatiom, but still i can't seem to figure out some things. So...here it goes.

Good to know you did your homework.

1- The reflux chamber. How does it looks on the inside, where does it sits, at what temp(in the early posts jetys recomended a lower temp, at the las page Beyond Bio, recomended top temp) this is my biggest unknown.

The confusion is there are many ways to skin a cat. So, the reflux chamber needs to be relatively large, so 1/4 the size of the retort, so many of us just partially fill our retort with hydrocarbons to be cracked, then the upper 1/4 of the retort is filled with some highly conductive and high surface material that will not melt. It could be terra cota tiles, wire, metal bug screening, etc. It is intended to avoid boil-over.

The temperature should be at least the level of your first condenser, so 300-400c. The lower the temperature, and the smaller size, of your reflux chamber, the more likely that you are going to get a plug in it. A plugged reflux chamber means kaboom!

2- The catalist chamber. It is inside the reflux, after or before?

Keep in mind that this is backyard DIY cat cracking, so, if this were the petroleum industry, then the feed would be shot through a fluidized bed of catalyst, then pass through the reflux chamber.

However, to simplify the design for the DIY, then the catalyst chamber could be combined with the reflux. Or the catalyst could be just inside the retort boiling with the hydrocarbons.

3- Should the first condenser be before the cooling tank or after it?

You cannot hope to get a reasonable extraction from the fluid stream with just one condenser. Most of us have staged condensers. I have 7 stages before the bubbler. Each condenser is after the trap (cooling tank) that collects the fraction.

4- would grapitated azbest rope/simple azbest rope be a good substituent for a seal? Maybe for replacing teflon tape in threads?

I am not sure what grapitated azbest rope is, nor is Google. My guess is you are talking about graphite cordage, or rope. It is too porous to use as a seal, however, there are seals made of graphite that work excellently as seals. However, I do not believe any of it is thin enough to function as a pipe thread seal. The best is just to use stainless steal tapered thread fittings and tighten them until the seal is leak tight, for any fitting that operates above 350c, otherwise teflon tape works great.

And last one, Beyond Biodiesel, and Excalibur, from what i have read you have some nice setups, also Jetys but he wasn't on the forum for a while -you may have done this already- but could you post some schematics, plans, photos, anything that can be a source of inspiration on the forum? That will be highly apreciated!

Both of us have posted boat-loads of photos here, and both of us have links to blogs, or forum threads, with our photos on them. Here is a link to a section of a forum that I run that has my (and others) pyrolysis work organized by topic.
Pyrolysis of Hydrocarbons

Thanks alot guys, i wish you a Merry Christmas and all the best!

Florin

Edit* Forgot to mention, i'm only using plastic, and i want to get as much diesel as possible.

Welcome, Florin, and keep us posted on your developments.

[fox32]

This is a great info, thank you for taking your time to post it!

I'we heard that the reflux chambers can be trouble makers so i'l be extra carefull about it, i also found an interesting video on youtube http://images1.okr.ro/auctions.v3/30...61-300_300.jpg and i see that their reflux chamber is at what apperas to be a 45 degress angle, it sounds interesting, i was thinking to replicate their design. Any thoughts on it? (it-s at 6.25).

The rope, yeah, it looks the same, only this one is made from asbestos, and yes again, it i too thick for screwing.

Also about the condensers, i have 3 of them, but after hearing about those 7 i'm thinking to add some more. Il put my plans, now they are on the notbeook, so as soon as i finish replicating them in paint i'l post them!

Thank you and all the best!

[fox32]

Okay, so i finnaly got to draw it, so i'm gonna also post all the details, not my best paint work, but wil do .

So, the reactor is made out of a steel pipe, about 1.5 m long, 20mm thick, with both ends welded, put inside an upside-down 200 l oil drum, with about 20 cm between the walls.

Through the bottom of the reactor i will have 4 hollow pipes, in a cross section to each side of the reactor, from the bottom of the reactor, exiting at an angle (was thinking 90*) and circulating air from the blower, through the inside of the reactor and between the reactor and the outer drum.
Much like a log water boiler, only that the pipes won't exit through the top.(not enough room for the lid, exhaust etc).
I'm thinking that this setup will be more efficient at heating the feedstock from the inside out , but it can also increase tar content the contact area being larger...

All of this insulated with fiberglass.

The condensers are 100 l electric water boilers, with their original
insulation. I'm planning to use them as this and strip them out if necessary.
The current design isn't final, i'm planning to see how it goes like this, and then maybe switch C2 with cooling tank, and so on.
I plan to keep the first one at around 200-220c, second at around 150-170 and third cold. As recomended on your forum, btw great link!

The wmo burner is still in perfectioning mode, nearly completed it, i went for this design. how to make a EASY waste oil burner - YouTube Still tweaking with it, trying to find the right hole dimension, and air to oil amount. If it won't work good, i think i will try a Turk design or gas burner.

The reflux chamber i'm thinking to put it at a 45 degrees angle, i saw this on a proffesional rig, an i'm thinking that id made sense, all the heavy stuf flowing back through the botom of the pipe and lighter gases above it.
The reflux chamber is made from 2 parts, the top one contains the catalists, the bottom one being the refluxer.
Hope that being that close to the reactor the temperature won't drop much and i wont need to heat it.

I was thinking that the exces gass could be directed to heat the condensers if neded.

Also, thanks for the over-boiling advice, i'l definetly add some chicken wire or something, didn't knew about this one.

Now, i'm just waiting for the final parts to arrive, i have about 90% of all parts, the reactor needs some welding,i'm not really sure about those pipes inside, so i'm trying to figure out the best output for this big puzzle!

Have a great day!

[Excalibur]

Florin

Thanks for posting, great effort and good plans. You have clearly taken the time to study so have set a good example for others.

Step by step. That's the way to proceed.

The reflux may need insulating. I see no problem with the 45* angle. Your three condensers will give you three fuels, tweak temperatures to achieve the required ones. ( I have only 1 condenser so I set temps to maximize diesel production only). Lathe swarf/turnings for the reflux is good. The water cooled condenser will require a water feed supply, else the water will get hot and become less effective.

Reflux temperature is something that you'll tweak to suit the product required. If you get wax, then decrease.

The retort will require lots of heat. More than you'd expect. Probably you'll end up fitting a flue pipe ( I speculate).

[Beyond Biodiesel]

This is a great info, thank you for taking your time to post it!

I'we heard that the reflux chambers can be trouble makers so i'l be extra carefull about it, i also found an interesting video on youtube http://images1.okr.ro/auctions.v3/30...61-300_300.jpg and i see that their reflux chamber is at what apperas to be a 45 degress angle, it sounds interesting, i was thinking to replicate their design. Any thoughts on it? (it-s at 6.25).

It really does not matter what the angle is, or where the retort is; however, in petroleum refining the retort is typically at the bottom of a fractionation column, which extends straight up for several stories.

Normally, a 5-gallon (20L) retort would be serviced by a 2 story (20foot/6m) fractionation tower; however, for me, and most DIY pyrolysis practitioners, such a high tower poses a serious design problem, so most of us have horizontal fractionation systems. My horizontal fractionation though has gotten too long at roughly 20 feet, so I am planning on stacking it up 4 feet (1m) high and about 8 feet (2m) long.

Also about the condensers, i have 3 of them, but after hearing about those 7 i'm thinking to add some more. Il put my plans, now they are on the notbeook, so as soon as i finish replicating them in paint i'l post them!

Thank you and all the best!

As far as I am concerned the more the merrier; however, I did discover that with my vapor stream rate, a 2ft (1m) water cooled condenser was sufficient. My condensers are staged roughly at 100c intervals from 300c to 0c

Okay, so i finnaly got to draw it, so i'm gonna also post all the details, not my best paint work, but wil do .

The drawing looks good. I assume you are insulating all of the heated sections of pipe in between heated condensers.

So, the reactor is made out of a steel pipe, about 1.5 m long, 20mm thick, with both ends welded, put inside an upside-down 200 l oil drum, with about 20 cm between the walls.

Sounds good, and I see that you are planning on burning some kind of fuel to heat your retort. It should work fine, but having flames near a pyrolysis unit just scares me too much, so I use electricity to heat mine.

Through the bottom of the reactor i will have 4 hollow pipes, in a cross section to each side of the reactor, from the bottom of the reactor, exiting at an angle (was thinking 90*) and circulating air from the blower, through the inside of the reactor and between the reactor and the outer drum.
Much like a log water boiler, only that the pipes won't exit through the top.(not enough room for the lid, exhaust etc).
I'm thinking that this setup will be more efficient at heating the feedstock from the inside out , but it can also increase tar content the contact area being larger...

An integrated heat exchanger on the retort sounds good, but troublesome to make.

All of this insulated with fiberglass.

Fiberglass insulation is only good to about 100c, so you will need some other kind of insulation. I am not sure what you have access to, but rock wool, or kaowool, or fire bricks are the more common insulators for this temperature. If they are not available to you, then there are effective alternatives. Here is a link to insulation investigations.
High temperature insulation

The condensers are 100 l electric water boilers, with their original
insulation. I'm planning to use them as this and strip them out if necessary.
The current design isn't final, i'm planning to see how it goes like this, and then maybe switch C2 with cooling tank, and so on.
I plan to keep the first one at around 200-220c, second at around 150-170 and third cold. As recomended on your forum, btw great link!

Thanks, for the recommendation of my forum. I believe 200c will be too high for fiberglass insulation. Your retort will need something as well. The steel outer barrel will work fine for insulation. And, maybe that will be all you will want, but you could use less heat if you insulated the outer barrel.

The wmo burner is still in perfectioning mode, nearly completed it, i went for this design. how to make a EASY waste oil burner - YouTube Still tweaking with it, trying to find the right hole dimension, and air to oil amount. If it won't work good, i think i will try a Turk design or gas burner.

The reflux chamber i'm thinking to put it at a 45 degrees angle, i saw this on a proffesional rig, an i'm thinking that id made sense, all the heavy stuf flowing back through the botom of the pipe and lighter gases above it.
The reflux chamber is made from 2 parts, the top one contains the catalists, the bottom one being the refluxer.
Hope that being that close to the reactor the temperature won't drop much and i wont need to heat it.

I found if I did not heat my reflux, then the retort would just reflux for hours and never progress.

I was thinking that the exces gass could be directed to heat the condensers if neded.

Also, thanks for the over-boiling advice, i'l definetly add some chicken wire or something, didn't knew about this one.

Now, i'm just waiting for the final parts to arrive, i have about 90% of all parts, the reactor needs some welding,i'm not really sure about those pipes inside, so i'm trying to figure out the best output for this big puzzle!

Have a great day!

Chicken wire should work fine for a refluxing medium. Looks good. Keep us posted.

[Excalibur]

Pic shows the reflux with what's believed to be rockwool insulation. So far, I like this better than kaowool. The reflux gauge is from a vintage Orion stove which reads in Fahrenheit. The needle points to the word Orion when the diesel is flowing well (approx 700f). I jest, my "stars are in alignment".

Some more figures and snippets of info:

The 180 liters made last week used 9 liters of diesel for firing. Keep in mind though that some retort gases are also being burned. At times the retort ran solely on those gases, other times the turk burner head was required to supplement.

I re-tested the diesel SG after filtering and at ambient temperature of around 20*C. It was .839.

The centrifuge didn't get completed so I pumped the batch through a strainer, then 5micron bag filter and finally a 1micron bag, all in one pass. The pump used was a 12v Mallory marine gear-pump. I adjusted the relief valve to reduce the flow a bit and give the filters an easier time.

The centrifuge target is 3840 rpm. According to a centrifuge rpm/diameter chart, the fuel will be subject to 2232g of force. Effectively, this gravity multiplying effect will accelerate the settling process. I plan to use a 12v Facet (aka tick-tick) fuel pump to trickle feed the centrifuge. I'm aiming to strip the fuel clean in one pass but we shall see what's possible.

I hope this stuff is of interest...?

[Beyond Biodiesel]

Thanks, Excalibur, it is very interesting.

[Excalibur]

I sorted through the video footage and put together this Orion clip

No time to celebrate, already I've given myself a sizeable list of upgrades and improvements. I want the centrifuge running with fuel feed pump plumbed and wired. The gas feed needs another revamp. Sight glass on the diesel reservoir needs replacement. Lengthen and insulate the flue for better draft. Revise the oil feedstock controls. Reflux thermocouple LCD display wired to 12v supply. A dedicated pump and 20m fuel delivery line to the van. So heaps to do.

Really, the main problem is keeping the gas feed ignited. The gas can be intermittent plus low pressure so it goes out then suddenly re-ignites with a loud backfire. Mooted was the possibility of using a dedicated LPG torch on minimum, like a pilot flame. Ever notice how a LPG propane torch can go out when put inside a vessel or pipe? I have various gas heater & oven parts.
Can anyone point to some good information on gas fired equipment?? Thanks.

[Beyond Biodiesel]

I sorted through the video footage and put together this Orion clip

Nice video

No time to celebrate, already I've given myself a sizeable list of upgrades and improvements. I want the centrifuge running with fuel feed pump plumbed and wired. The gas feed needs another revamp. Sight glass on the diesel reservoir needs replacement. Lengthen and insulate the flue for better draft. Revise the oil feedstock controls. Reflux thermocouple LCD display wired to 12v supply. A dedicated pump and 20m fuel delivery line to the van. So heaps to do.

Nice upgrades

Really, the main problem is keeping the gas feed ignited. The gas can be intermittent plus low pressure so it goes out then suddenly re-ignites with a loud backfire. Mooted was the possibility of using a dedicated LPG torch on minimum, like a pilot flame. Ever notice how a LPG propane torch can go out when put inside a vessel or pipe? I have various gas heater & oven parts.
Can anyone point to some good information on gas fired equipment?? Thanks.

The warehouse complex where I am doing my pyrolysis project has an air conditioning and heating business. He has a scrap pile of dead heating units and air conditioners that piles up near the dumpster. I have examined the gas-fired heating units. They all have 2-3 spark plugs in them with a high voltage power supply, and it looks like the spark plugs run continuously. So, you might try that.

[fox32]

Excalibur,

Thank you, i tried to undesrtand the principle as much as possible, so i can replicate it in a safe way. And i recommand it to anyone, READ the FORUM. At least the first 40 pages.

Also thanks for the tips, didn't thought of insulating the retort, also your reflux looks bigger than i imaginated, you also have catalist inside? An very nice video, i'm most impressed with your skills in adapting a car injection pump into a turk enginer. Very nice work!

I also plan on making as much diesel as possible, in your experience is more conveniant to have just a single condenser? And the naptha and lighter gases condense in the bubbler or get burn along with the uncondesable gases? I don't want to use adittional condensers if i don't need them. Looks simpler with just 1.
Thank you, very nice setup, keep it going!

Beyond Biodiesel,

Thank you for the insight, didn't thought to insulate the exposed connection pipes, also didn't knew that fiber glass would melt at ~200*c so, you helped me dodge a bullet. Btw is any way to test if the fiber in my condensers is made of glass, would it burn in open flame? They have diferent colours and consistency.

I can't seem to find rockwool in here, but i found some ceramic wool, the problem is that is so darn expensive. Just as the electricity, so this is why i'm using open flame, also wmo is quite cheap. Also thanks for the insulation link, that info is valuable!

Also the idea of using another heater on top of my reactor is starting to scare me too, so can i ask you how you heat your retort?

Now i can't decide on my heat exchanger design, and all the holidays aren't helping, it's closed everywhere and i still didn't found a proper lid, some parts are caught in postal offices.... well i guess i'l just have to wait untill the next year, also my welder won't work in the holidays, so you could say i'm on a forced break!

Thank you guys, all the best!

[Col]

burner system

I have examined the gas-fired heating units. They all have 2-3 spark plugs in them with a high voltage power supply, and it looks like the spark plugs run continuously. So, you might try that.

On my (fire tube) boiler burner (small Dunphy unit, good and reliable) at work it has a couple of electrodes which arc up to ignite the sprayed / atomised light oil I use as boiler fuel. The electrodes seem to be run off 240V, 10A max (I'm not the best at reading electrical diagrams). These electrodes are positioned just in front and to the side of the fuel nozzle (far enough away to avoid carbon build up on the electrodes and close enough for ignition) and start arcing in conjunction with the fan blowing 12 seconds before the fuel pump kicks in. They do not get 'wet' in the fuel spray, but ignite the vapours off to the side which in turn light the rest of the fuel. They are regulated by a light sensor. They don't arc up if there is light / flame in the combustion chamber as the injected fuel will ignite when it reaches the existing flame so the electrodes are not necessary at this point. If the flame goes out for some reason (poor atomising, water in the fuel, fuel line blockage) the light sensor turns the fuel pump off and rings an annoying bell until someone goes over to see what is wrong. There is a safety delay of about 30 sec before I can restart the burner, allowing the draft created by the tall exhaust flue to suck any excess vapours out of the combustion chamber before the fuel pump can add more volatiles to the chamber. Backfires are rare but there is a delay between flame failure and the burner shutting down so backfires are possible. I presume the electrodes arc up again at this stage because the flame will sometimes ignite anew if the problem was temporary (a few seconds), but if the problem persists the burner shuts down.
I have bought (though not yet tested) a Crown C-10 Flame Detector from ebay for less than $10 which I intend to use for this purpose.
I will be trying to add some of these features to my burner system eventually. Perhaps they are of help to others.

Regards
Col

[Excalibur]

BB & Col
Thanks for the comments. Actually I've got two of the central heating "gun burners" (we call them), however both have dead ignition transformers.
I have a couple of possibilities to find a transformer, one won't be known at least till 6th Jan when the man gets back from holiday. New ones on Ebay but at 5kg means shipping would make cost more than double.
The one I had running before it lost the spark, really looked good and I was excited about the prospect. One is 11amp and I think the other is 10. That's over 2KW, just for spark. But what a spark! The force of the fan stretches the spark into the path of the diesel. I was amazed, I never knew spark could be affected by wind.
.
One of the gun burners I picked up.

I have another thing to try in the meantime. Google found details of gas fired ceramic kilns.



Just by chance and without realizing it, the forced air burner design above is what I used on an earlier prototype. That was more stable. The bubbler was creating a stop~start nature to the gas flow which did occasionally flameout.

If there's time before gun burner parts turn up, I'm going to fit a number of gas nozzles in various locations and using flexible hose, connect each one in turn. In addition I think I'll make the nozzles small, not the open port style of before. Also when I first fire up the turk from cold, I'll siphon all the gases to the gasjar so that when the retort hits the target I'll kill the IP and have a quantity of gas as a buffer.

Fox32
Yes, please read the forum. There is a wealth of information and the best part is that it is free and there are gems amongst the pages! You only need to do a little harvesting and separating wheat from chaff.

Retort insulation is essential for efficiency while the process will work without, the heat/energy loss will be huge. My first two prototype attempts were un-insulated wood fired. Wood was free and in abundance though. Tip:When you do go with insulation, do so in such a way as to be able to recycle it to your next generation of retort.

The reflux dimensions are on my DIYdiesel blog "reflux page" along with the making plus "retort vessel page" has how the flange and connecting pipe is welded.

Like yours, my focus is on diesel and I want to maximize the output of that product even at the expense of other fraction/s. So I have 1 condenser. The reflux temperature aims to force only the release of nothing heavier than diesels' heaviest fraction while on the downstream side of the diesel reservoir, only the most volatile fraction/s are driven off. In this way, I save the maximum range of fractions that makes up diesel. And yes, burn the rest as heat.

[Beyond Biodiesel]

I also plan on making as much diesel as possible, in your experience is more conveniant to have just a single condenser? And the naptha and lighter gases condense in the bubbler or get burn along with the uncondesable gases? I don't want to use adittional condensers if i don't need them. Looks simpler with just 1.
Thank you, very nice setup, keep it going!

The thing that a lot of people do not get is light fractions, like naptha, can be blended with heavier practions, like motor oil, to make diesel fuel. So there is no reason not to collect the lighter fractions. That is why I collect them.

Beyond Biodiesel,

Thank you for the insight, didn't thought to insulate the exposed connection pipes, also didn't knew that fiber glass would melt at ~200*c so, you helped me dodge a bullet. Btw is any way to test if the fiber in my condensers is made of glass, would it burn in open flame? They have diferent colours and consistency.

If you are not sure that an insulation can handle the heat, then hold i over a flame, like a match or candle. If it melts or burns, then it cannot handle the heat.

I can't seem to find rockwool in here, but i found some ceramic wool, the problem is that is so darn expensive. Just as the electricity, so this is why i'm using open flame, also wmo is quite cheap. Also thanks for the insulation link, that info is valuable!

To the best of my knowledge rockwool, kaowool and ceramic wool are all the same thing. If you are having trouble finding high temperature insulation, then search out art stores and ceramic supply stores, because they are likely to have high temperature insulation for ceramicists.

But you can also make your own high temperature insulation out of a wide range of materials. For instance, if there are any volcanoes in your region, then there might be pumice stone in large quantities where you can just drive a truck up to a public quarry and shovel it in. Diatamoceous earth can also be used as insulation.

Insulation can be made out of a composite of materials. For instance the first layer has to handle 800F (425c) But it need only be 1" 2.45cm) thick. The outer layers can be sheet rock, or even cardboard with layers of sheet metal in between.

Also the idea of using another heater on top of my reactor is starting to scare me too, so can i ask you how you heat your retort?

The first 5 stages of my pyrolysis unit are heated with electrical resistance heaters. The bottom of the retort has a simple element from an electric stove, then band heaters on the sides, then high temperature line wrap on the tubes, then the next stage heated condenser has nothing more than an electric frying pan as its heater, the the next one uses a plat warmer, etc.

Now i can't decide on my heat exchanger design, and all the holidays aren't helping, it's closed everywhere and i still didn't found a proper lid, some parts are caught in postal offices.... well i guess i'l just have to wait untill the next year, also my welder won't work in the holidays, so you could say i'm on a forced break!

Thank you guys, all the best!

Doing pyrolysis safely is a big deal, and expensive. So, take your time.

[bgKiril]

Hi Dudes ,

First of all, greetings from Bulgaria
I have made a machine similar to yours and had tested with car tires. I get liquid shown to the photos.



My question is how to clean that liquide oil ? I understand that that liquide i got is both diesel and gasoline. How to seperate them ?
I tried with putting active charcoal but nothing happen. Is there any chemical that could to clean that liquide from any hard parts inside ?