How to turn plastic waste into diesel fuel cheaply

[dutchdivco]

Ah

Thank you, Asad, I stand corrected. I thought i had recalled that 300+ celsius was sufficient, I was obviously in error. Interesting that the difference in Temp can have such a major effect on the end product; the amount of vapour as opposed to the amount of liquid fuel.

I suspect each person will need to experiment with adjusting the temps, based on the raw material (plastic) they are using, as well as the design of the processor.

Reflux, as I understand it (someone correct/clarify, if I've got this wrong, please!) is this; As you heat the plastic, some of the material doesn't 'process' with the initial heating; it forms liquid droplets that are caught up with the vapour, and carried 'forward'; but it hasen't changed into either a liquid or vapour fuel; its just melted plastic in liquid droplet form.
The reflux chamber is to catch this material, and return it to the reactor, so it will get 'processed'. Now, guys, have I got this right?!!!
The reflux chamber just need to be filled with something that will 'catch' this unprocessed material; glass marbles (I believe) have been suggested. My understanding is you want the reflux chamber at about the same temp as your processor, and located above the processor, so this 'captured' material can be returned to the processor via gravity.

Anyway, thats my understanding, and I'm glad you asked, as it gives me an opportunity to see if I'm understanding it, myself. Jim

[fibuslitero]

To dutchdivco

Hi:
What I placed inside the reflux tower was pumice stones.
This means millions and millions and millions of little caves and caverns that the vapours must travel through.
Until the particles are not "thin" enough they cannot pass through this caverns so once they find these obstacles they return to the reactor to be "re cooked".
This is why reflux tower + catalyst means in the case of polyethylene obtaining liquid instead of paraffin.
This is at least my personal experience.
Hope it helps

Thank you, Asad, I stand corrected. I thought i had recalled that 300+ celsius was sufficient, I was obviously in error. Interesting that the difference in Temp can have such a major effect on the end product; the amount of vapour as opposed to the amount of liquid fuel.

I suspect each person will need to experiment with adjusting the temps, based on the raw material (plastic) they are using, as well as the design of the processor.

Reflux, as I understand it (someone correct/clarify, if I've got this wrong, please!) is this; As you heat the plastic, some of the material doesn't 'process' with the initial heating; it forms liquid droplets that are caught up with the vapour, and carried 'forward'; but it hasen't changed into either a liquid or vapour fuel; its just melted plastic in liquid droplet form.
The reflux chamber is to catch this material, and return it to the reactor, so it will get 'processed'. Now, guys, have I got this right?!!!
The reflux chamber just need to be filled with something that will 'catch' this unprocessed material; glass marbles (I believe) have been suggested. My understanding is you want the reflux chamber at about the same temp as your processor, and located above the processor, so this 'captured' material can be returned to the processor via gravity.

Anyway, thats my understanding, and I'm glad you asked, as it gives me an opportunity to see if I'm understanding it, myself. Jim

[Asad Farooqui]

pumice stone

Hi:
What I placed inside the reflux tower was pumice stones.

Hello Fibuslitero ;
Did U check the liquid fuel obtained by catalytic action of pumice stone is of what fraction-range ?
Is it gasoline + kerosine range , Say upto 275 celcius .
Or
They are heavy Diesel fraction upto 375 celcius

[dutchdivco]

Just to clarify

for ALL of us; reflux is as I described earlier, 'catching' plastic which hasn't processed, and 'holding it back' or returning' it to the processor. Catalyst is something different; a catalyst is something which, though not consuned in a chemical reaction, 'triggers', causes or promotes a chemical reaction. In this case, it 'triggers, causes or promotes' breaking the chemical bonds, to change the length of the hydrocarbon molecules.

And are you saying pumice can do both? i.e. act as a catalyst as well as acting as a 'reflux' agent? Thats handy! It would also be useful to know if different catalysts can give different results, as far as what the end product is, i.e. one catalyst will give more of the gasoline/kerosene, whereas another will yield more diesel.Jim

[fibuslitero]

To Asad

Hi Asad:
At this moment I am renewing my lab scale equipment in order to control temperatures.
I am afraid I cannot answer properly to your question at this moment, just by intuition.For sure I used really high temperatures out of control because my furnace is very powerful; I uploaded some pictures before in page 26.
What I can say is that pumice stone worked fantastically and the fuel obtained works very well in the Perkins motor we have for our tests.
What I think is that it ranges the three fractions for sure, there are colour changes in the liquid.
There is a green layer on the surface (gasoline) and in one experiment it was captured using water cooling and after separation it worked well in a electric generator.
I am focused on building a distillation machine for the whole mixture rather than separating them on the run.Where the Perkins motor is used is a very cold place so at this moment makes sense using all the fractions together.
Later we will try to perfect the separation while running the process.
As soon as I try destillation for the three mixed fractions following the temperatures you have indicated in the forum I will tell you (maybe using ooVoo videoconference ).

PD:If I find a picture of the layers that can be seen I´ll upload it asap

Hello Fibuslitero ;
Did U check the liquid fuel obtained by catalytic action of pumice stone is of what fraction-range ?
Is it gasoline + kerosine range , Say upto 275 celcius .
Or
They are heavy Diesel fraction upto 375 celcius

[fibuslitero]

To dutchdivco

Hello dutchdivco:
I was just trying to share my experience with the combined effect of the reflux chamber + catalyst inside; imagine how happy I was when after two runs obtaining paraffin I suddenly obtained fuel just with slight changes in the setup (just following former experiences from our friends in the forum).
I am not an expert but I am sure using different catalysts you can alter the different yields but this depends on various factors (temps, feedstock, agitation...).
Here we try to use cheap elements and I saw in Youtube pumice stone was used by a teacher to crack paraffin so I went to a shop, I bought lumps of pumice and I can say that in my case it worked soooo fine

for ALL of us; reflux is as I described earlier, 'catching' plastic which hasn't processed, and 'holding it back' or returning' it to the processor. Catalyst is something different; a catalyst is something which, though not consuned in a chemical reaction, 'triggers', causes or promotes a chemical reaction. In this case, it 'triggers, causes or promotes' breaking the chemical bonds, to change the length of the hydrocarbon molecules.

And are you saying pumice can do both? i.e. act as a catalyst as well as acting as a 'reflux' agent? Thats handy! It would also be useful to know if different catalysts can give different results, as far as what the end product is, i.e. one catalyst will give more of the gasoline/kerosene, whereas another will yield more diesel.Jim

[fibuslitero]

To Asad

Hi:
The fuel I obtained with the catalytic action of pumice stone resembles 100% with the one in the picture.
I have to say the photo is not mine but once I found it in the internet I captured it because it was surprising how similar it was.
Three colours - layers can be seen.
As I said I am trying to prepare a little refinery for this mixture because maybe for my case could be easier to prepare a simple setup for the immediate obtention of fuel and after that refining the three fractions depending on the needs.
The fact is that this worked fine in our engines

Hello Fibuslitero ;
Did U check the liquid fuel obtained by catalytic action of pumice stone is of what fraction-range ?
Is it gasoline + kerosine range , Say upto 275 celcius .
Or
They are heavy Diesel fraction upto 375 celcius

[dutchdivco]

if

you've got 3 distinct layers, than you have 3 different liquids, with a significantly different specific gravity for each; should be fairly simple to seperate the 3, without heating.

Or, incorporating seperating into the initial process. Would be a shame to have to heat the liquid up again, in a seperate process, seems to me. Expending additional energy.

Good to here how well the pumice stone worked for you! And yeah, its 'dirt' cheap!Jim

[tony steinke]

I previously stated that I could get a 1500 lb bale of post consumer plastic for $80, thats what I was told over the phone. When I went to purchase some for experimenting, they wanted $500 per bale. Ouch! Now I am forced to collect post consumer plastic on my own, but it's so bulky that it must be processed in some way in order to get enough stock into a reactor. So what's the best way? Should I compact it and make bales ? melt it down ? or grind it ? I thought about building a grinder using 40 carbide tipped saw blades, each one separated by an eighth inch spacer. This would be wide enough to grind most post consumer plastics. It would also be a lot of labor. Any imput on what others are doing, and how they are doing it, would be greatly appreciated.

[imakebiodiesel]

Just to recap on the explanation of the reflux column. When the molten plastic reached 370 C cracking begins. Vapour which contains fully cracked and partially cracked molecules rise up into the column and come in contact with the cooler surfaces in the column. the partially cracked molecules condense into liquid and fall back into the reactor for further cracking. The fully cracked molecules pass through to the next stage.
Different catalysts at different temperatures in different reactors will produce different mixes of fuels. At this stage I dont think it is possible to lay down simple rules about the behavior of the different catalysts. The best approach might be to build a small reactor and test numerous catalysts and mixtures of catalysts untill you find one that works for you. Then carefully up scale using as similar a layout and process as you can to you roriginal small reactor.

[dutchdivco]

follow up

Tony, yeah, thats a big jump in price, sounds like 'bait and switch'; did you get an explanation for the difference in price between the quote over the phone, and the quote in person?
Still, might be good to remember this; Miles per gallon is really a worthless calculkation, its dollars per gallon that is the key. Similarly, $500 per bale might not be a bad price, IF you got enough useable fuel out of a 1500 Lb bale to make it worthwhile. In other words, if you got enough fuel out of a 1500Lb bale, that it came out costing you, say, $0.20 per gallon, (just as an example.
Can you get smaller amounts from that source, to experiment with? The source I talked about, that I found earlier, had bales of scraps, (it looked similar to carpet underlayment, i.e. scraps and trimmings cut from a sheet or roll), or they had it already shredded into something like sawdust, only bigger chunks, say 1/2".
I don't know what kind of post consumer plastic ypour considering; milk bottles, etc? I had wondered about an industrial strength paper shredder. Also wondered about a 'chipper' like landscaping crews use for tree limbs.
Might be good to do some research, and see whats already been done/ out there, before you make your own; might find an old, used unit you can get or refurbish, or at least get sonme ideas on design. Can you get a chance at that supplier, to see what THEY use for shredding, for instance? The design you describe seems like it might be overkill. And I recall once, we were doing a job where we needed to cut 1" styrofoam into (around) 6" or 8" wide pieces, on a table saw; after only a little while, we had to stop, because the material was binding; the saw blade had gotten so hot it warped; we had to wait for it to cool down to continue. I was surprised, because we could have ripped hardwood lumber on this same saw for hours, and the blade wouldn't have gotten hot enough to warp.
Heard of a large scale sawmill, where they had something called a 'hammermill', (I think it was); all or the unusable scraps went on a conveyor, and wer fed to this thing, which had a big drum with what looked like sledgehammers on the surface of it. Maybe 2 drums, I don't know. It pulverised the wood into sawdust. I'm just saying, even if you build it yourself, I think it would pay to research how others have already detirmined is the best way to shred plastic.

Imakebiodiesel; Yeah, thanks for the clarification, thats about how I had come to understand it, but you express it clearly. Jim

[tony steinke]

Jim, I estimated that based on 9 lbs of plastic for every gallon of liquid fuel, that comes to roughly $3 per gallon. That's not what I was originally hoping for, especially after reading the first few pages of this forum. As far as the $80 original quote goes, I have not a clue what happened there. The 1500 lb bale is as small as it comes and they typically sell in lots of 21 ton trailer loads. The plastic is sorted by recycle number and baled, nothing more. Concerning the method of consolidating plastic stock, I have talked to some people in the plastic business. They say that plastic is a tough nut to deal with without the help of an industial plastic grinder, shredder, or baler. Very pricey even when used. I have a sizeable garden shredder, but it could not do the job. About the heating of the saw blades, I've had the same experience. I got the idea from a website that had already fabricated the forty blade one. They were in a remote area and this was their answer to most of their plastic waste. I emailed them, but they did not respond. I have tons of free post consumer hdpe at my disposal, but without a practical and economical way to consolidate it, it's useless.

[Marso Green]

Rectifier Column approach versus multiple independent condensers in series

Hello everyone,

I've been lurking in the background for a while, trying to absorb and learn all of this, with the hope to contribute effectively in the near future.

While I'm not quite at the point of demonstrating a build just yet, I wanted to ask a question on Diesel/Gasoline/Kerosene separation.

It seems that although the cracking variables (heat source type, heat distribution, feedstock variability, temperatures, refluctor design, catalyst type, etc) are essentially known, an optimum design (or a design that is flexible enough) has yet to be defined. Some of the successful designs that have been demonstrated so far seem to be on their way, but none without the valiant efforts of the members who are building them.

My question is, is there a reason why duplicating the rectifier columns that oil refineries use, is not a good idea? It seems to me that the time, amount of effort involved, as well as cost of coming up with something that works with 3 condensers and testing several variations of reflux designs, are equitable to that of building a scaled down version of a proven rectifier column design

Any thoughts on that? Am I way off? And on that subject, is there an open source design out there for a rectifier column that one could consider building?

thank you
Marso Green

[imakebiodiesel]

The rectifier columns used in the oil industry are designed using computer modelling programs for a specific set of fluids, temperatures and gas velocities. Simply making a small scale version of one would not necessarily work. If you construct 3 or in my case 2 separate condensers it will be a much more flexible system. For instance, by adjusting the length of pipe between the reactor and the two condensers I can adjust the gas temperatures in each condenser.
In my " hot " condenser I can adjust the internal temperature between 50 and 250C. When starting out flexibility is much more important than overall efficiency.

[markusov]

I wish to all partakers in this forum a Happy New Year, good luck and progres.

Markusov