How to turn plastic waste into diesel fuel cheaply

[andriywovk]

Hello!
I done measuring and results are on 75C degree weight of Diesel is 740 grams on 100c degree is was 770C.
The plastic was mostly PP 80%^ and the rest HDPE the reactor was running on 355C this is consequence that my chimney was small and kiln was full of smoke so the flame could not rise, this will be solve till next test, even with this temperature it should be more then enough to crack the PP plastic the odd thing was that there was no wax at all.
The reflux tower with catalyst was working on 210C just as it needed. For catalyst I used zeolite.
The machine have two condenser and the final one was working most of the time at 100C so it should yield a heavy fraction of diesel which didn't happen.
I do not have idea why I yield so light Diesel, what I can do is to take control point on first condenser to see what do I get in reflux tower and to be sure that there was not (or was) mixing with light fraction on the extraction point, the extraction point is measured with two sensor so I could be sure 100% that temperature is right.
If any body have an idea what happen that I get so light fraction pleas write.

Your reflux tower targeted for gasoline, not for diesel fraction. Diesel fractions are 170-360C, at 210C only lightest of them ewaporate. Most will reflux to reactor and crack again and again till gasoline fraction. You should rise the reflux temperature to at least 300C. At this point only wax will flow down to the reactor for second crack. Diesel will ewaporate (and gasoline too, of course).
If you can't rise the temperature of the reactor to 440-450C (the reflux will heat by vapors and maybe you should cool it down to at least 320C. But it is possible that a temperature balance will be established by vapor flow at 300-315C, the best interval), try a heat insulation for the reflux.
In my experiment of PE cracking, till 440C at the reactor there was no noticeable oil in the condencers. The temperature of the reflux didn't rise at all, because there was no cracking yet, so no vapor flow, so no convection heat transfer to reflux! The reflux's temperature rose very slowly for at least two hours, and all this time the entire meager amount of the diesel fraction could not escape the reflux column due to lack of temperature. It was re-cracked and therefore formed a little gasoline fraction. The reflux temperature was already about 200C. Then, when the reactor temperature reached 450C, the degree of cracking increased almost instantly, the reflux temperature began to increase rapidly due to the rapid flow of hot vapors, and at 320C instead of liquid, a wax appeared in the condensers.

[jonathan]

Good morning everybody around the world. Can you post photos setup and maybe some info like tempretures ecc ecc? And maybe fuel products.

[Jordan14]

Thank you all on respond, right now I'm on holiday to clear my head after Tuesday I will respond on your writing and with a lot of data so we could being better concludes, I have a very good idea where I made mistake and what I must do before even think to run again machine.
With God help we will make our oil refineries

[jonathan]

THANKS JORDAN im glad i hear from you and other members. Have a nice holiday and stay safe.

[jonathan]

Good morning. I want to try black waste oil continous system. Can someone help me about oil inlet pipe,? Inlet feed pipe just goes down the retort vessel? Thanks

[Jordan14]

Greetings!
I start to work on schemes of the process so it could be better understand how it work, I will also picture the products made in November and now (They are very stable without wax all tested on minus) soon I will publish, with the proper comments, Andriy gave good material for thinking.

[andriywovk]

Greetings!
Andriy gave good material for thinking.

I want to express a few more arguments.
1. All individual polymers (of course, I mean only hydrocarbon polymers PE, PP, PS) have the same character of DTG curves, but the cracking start temperature and the maximum cracking temperature are different.
They all behave like milk that is about to boil: you lower the temperature a little and it doesn't boil yet, you increase it a little - and the foam has risen rapidly and gone outside the vessel. It is extremely difficult to regulate the process, because a minute ago you had to heat the reflux so that the diesel fraction could evaporate to the condenser, and now you have to cool the reflux so that no wax gets there. I see a fairly simple solution as an alternative to complicating the equipment: do not use individual polymers as raw materials, but always use a mixture of them. Polystyrene degrades first, its free radicals catalyze the rupture of other types of polymers, and they mutually inhibit the rate of decay of polystyrene. When the reactor temperature rises to a maximum for polypropylene degradation, it is insufficient for maximum polyethylene decomposition, so the process of mutual catalysis and inhibition continues. In general, much better process control is provided.
DTG curves.jpg

[andriywovk]

2.From the work of Japanese authors, who posted data on the properties of cracking products of individual polymers (I cite three relevant tables here), I concluded that PE and PP will not produce liquids with a specific gravity greater than 0.8. But for a diesel you need at least 0.82! Instead, PS will give an excess weight of at least 0.93. Further, neither PS nor PP will provide the required viscosity - for PP products it will be no more than 1.6 centistokes, and for PS products - barely 1.1 centistokes. The diesel requires at least 2 centistokes, and can be provided by PE only, although the temperature in the reactor must be at least 440C. In addition, this temperature is necessary to increase the average molecular weight of the products to the level of the diesel range. This is the second set of arguments in favor of using a mixture of three polymers as a raw material instead of one.
PE cracking.jpg
PP cracking.jpg

PS cracking.jpg

[jonathan]

Thanks ANDRIYWOVK for this info. It could be good that those already do this project post photos of system and fuel they produce.

[Jordan14]

First picture is representation of my machine, with numbers are marked all vital parts.

1. Reactor
2. Cyclone
3. Wax collector
4. Reflux tower
5. Condensers
6. Liquid collectors (Diesel, Gasoline, Petroleum)
7. Bubbler

Blue colored part should be rebuild or build total new.






First with 3 bottle from left side to right represent:
The gasoline from November, the gasoline from last running and Diesel from last running

The last year gasoline was collected from 54 to 65C degree
This year gasoline from 55 to 75C degree

Diesel taken around 100C Degree ( there is and batch from 75 to 100C)

The picture of gasoline collected from 55 to 65C degree




The picture of temperatures from left to right (red numbers are the right one)

1. Reflux tower
2. Condenser 1
3. Reactor
4. Control temperature sensor at the end of condenser 2
   the reflux tower and reactor temperature reach the biggest value during the work, it was taken after start cooling condenser and had drop ot temp value in condenser in short period most was around 100C.
   
   
   

   Your reflux tower targeted for gasoline, not for diesel fraction. Diesel fractions are 170-360C, at 210C only lightest of them ewaporate. Most will reflux to reactor and crack again and again till gasoline fraction. You should rise the reflux temperature to at least 300C. At this point only wax will flow down to the reactor for second crack. Diesel will ewaporate (and gasoline too, of course).
   If you can't rise the temperature of the reactor to 440-450C (the reflux will heat by vapors and maybe you should cool it down to at least 320C. But it is possible that a temperature balance will be established by vapor flow at 300-315C, the best interval), try a heat insulation for the reflux.
   In my experiment of PE cracking, till 440C at the reactor there was no noticeable oil in the condencers. The temperature of the reflux didn't rise at all, because there was no cracking yet, so no vapor flow, so no convection heat transfer to reflux! The reflux's temperature rose very slowly for at least two hours, and all this time the entire meager amount of the diesel fraction could not escape the reflux column due to lack of temperature. It was re-cracked and therefore formed a little gasoline fraction. The reflux temperature was already about 200C. Then, when the reactor temperature reached 450C, the degree of cracking increased almost instantly, the reflux temperature began to increase rapidly due to the rapid flow of hot vapors, and at 320C instead of liquid, a wax appeared in the condensers.

Your reflux tower targeted for gasoline, not for diesel fraction. Diesel fractions are 170-360C, at 210C only lightest of them ewaporate. Most will reflux to reactor and crack again and again till gasoline fraction. You should rise the reflux temperature to at least 300C

I agree I didn't achieve wanted temperature the exhaust gases are not enough to heat my reflux tower.
My seeing of solution is to put gas burner and to put smaller amount of reflux material, right now is around 25% in weight of plastic mass in two cassettes, so to pull one cassettes (to leave some 15% of the mass) and with additional heating it should be enough. I believe that on first cassette I have good temperature for cracking but it loose when goes at second.
Do you have some additional material about temperature cracking in reactor tower in form of some research!?


At this point only wax will flow down to the reactor for second crack. Diesel will ewaporate (and gasoline too, of course).



Between reactor and reflux tower I install the cyclone so the wax can not back in reactor, in reactor is back after opening special valve on higher temperature, this how I prevent multiple cracking of wax and also keep clean reflux material as char at least most of him stay trapped by cyclone.







I

f you can't rise the temperature of the reactor to 440-450C (the reflux will heat by vapors and maybe you should cool it down to at least 320C. But it is possible that a temperature balance will be established by vapor flow at 300-315C, the best interval), try a heat insulation for the reflux.
In my experiment of PE cracking, till 440C at the reactor there was no noticeable oil in the condencers. The temperature of the reflux didn't rise at all, because there was no cracking yet, so no vapor flow, so no convection heat transfer to reflux! The reflux's temperature rose very slowly for at least two hours, and all this time the entire meager amount of the diesel fraction could not escape the reflux column due to lack of temperature. It was re-cracked and therefore formed a little gasoline fraction. The reflux temperature was already about 200C. Then, when the reactor temperature reached 450C, the degree of cracking increased almost instantly, the reflux temperature began to increase rapidly due to the rapid flow of hot vapors, and at 320C instead of liquid, a wax appeared in the condensers.

The problem with my reactor is that chimney is to small, so I will build addition one at that should be enough, the temperature on raising should be around 15C degree on 10 minutes after 280 even faster.
I agree I should have around 430 C temp for reactor and 360C temp for reflux,
Oour results are different I start to get gasoline around 280C and on till 350 it become wild, I collect gasoline in to batch one between 55 and 65C (the flash point of diesel is 61,5C) and another from 65 to 75C where start to coming diesel in visible form. The diesel that I got have nice diesel texture why is light I will write in conclusion.
There is chance that temperature in reactor didn't shown correct as sensor is at outlet pipe and do the foam in upper part of kiln temperature build up in lower part of kiln so in one moment the button of the reactor become red it was probably around 800C so it could crack whole material and not to show as reactor have height of 2 meter, I will not open the reactor to check until I prepare for next running because after reflux tower I have chemical reaction on metal (HCL acid).
I also do not have wax after reflux tower.




Conclusion
One of the biggest reason why I got light diesel is because I dint made proper diesel/gasoline/petroleum separator, it was a vulgar system with one vessel and hope that diesel will stay and gasoline, petroleum will leave in gas state which probably didn't happen, the sgW was 780 grams which is the same number that other members of this forum get without separation of fractions.

In sketch of my machine I mark with number 6 are the separation vessels,I'm forced to made them under the angle as I do not have enough height, the question stay how big should they be.


About their design I will write later, to you have any experience with them?

[jonathan]

Thanks JORDAN14, I THINK YOU GOT MISTAKE IN FIRST PHOTO AND NUMBERS DESCRIPTION.

[Jordan14]

Thanks JORDAN14, I THINK YOU GOT MISTAKE IN FIRST PHOTO AND NUMBERS DESCRIPTION.

Yes I did I will correct right away, also i made mistake for temperature of gasoline from November it is 54-65C not 54-55C
There is and problem with HCL but that's not now important.

[Jordan14]

2.From the work of Japanese authors, who posted data on the properties of cracking products of individual polymers (I cite three relevant tables here), I concluded that PE and PP will not produce liquids with a specific gravity greater than 0.8. But for a diesel you need at least 0.82! Instead, PS will give an excess weight of at least 0.93. Further, neither PS nor PP will provide the required viscosity - for PP products it will be no more than 1.6 centistokes, and for PS products - barely 1.1 centistokes. The diesel requires at least 2 centistokes, and can be provided by PE only, although the temperature in the reactor must be at least 440C. In addition, this temperature is necessary to increase the average molecular weight of the products to the level of the diesel range. This is the second set of arguments in favor of using a mixture of three polymers as a raw material instead of one.
PE cracking.jpg
PP cracking.jpg

PS cracking.jpg

As I understand this is cracking without catalyst?!
Did they separate fraction or all liquid fraction where collected in one vessel?
From the book Feedstock Recycling and Pyrolysis of Waste Plastics, where are done experiments with catalyst the numbers are different.
Here parts from the experiment where there was no separation of light and heavy fractions, on first diagram is represent the sgW for type of plastic and in second the result experiment.
The name of script "Thermal Cracking of Virgin and Waste Plastics of PP and LDPE in a Semibatch
Reactor under Atmospheric Pressure"

[jonathan]

Jordan14 as in past i read alot theres not hcl proplem if you use the right plastics as long thry are clean and without papers.

[Jordan14]

Jordan14 as in past i read alot theres not hcl proplem if you use the right plastics as long thry are clean and without papers.

Thanks on fast response!
i didn't start to work on HCL problem but it could be problem in cellulose as there was residues from paper glue (the white one), this batch was clean so I will see how it looks when i open the reflux tower, it made huge job to clean condensers and pipes, I will picture how oxidation looks.