How to turn plastic waste into diesel fuel cheaply

[keval]

can u plz explain the use of bubbler nd how to use it nd if I dont use it then does I get ma fuel or not

[Excalibur]

A bubbler provides important safety aspects like as a flashback arrestor.
I posted up a Youtube video on how to make a simple bubbler for cheap or free. No one can say they can't afford one of these.
Caution: the vapor stream should already be cooled sufficiently before entering the bubbler!
DIY Bubbler for cheap

[MasterBlaster]

I don't normally read this thread but you may like to know this:

16-year-old discovers catalyst to turn Egypt's plastic waste into biofuel | MNN - Mother Nature Network

[waterboost]

Catalyst

The Catalyst is xeolite.... Titanium Dioxide is another good one... Anything ionising...

[Beyond Biodiesel]

can u plz explain the use of bubbler nd how to use it nd if I dont use it then does I get ma fuel or not

Keval, the bubbler has a number of important functions.
1) A bubbler works as a primitive check valve to prevent oxygen from entering the exhaust stream.
2) A bubbler provides positive feedback for whether your reactor is still emitting volatiles.
3) A bubbler also provides a simple but effective means of reducing some toxic gasses.
4) Hydrogen fluoride gas (HF) in the flue stream of a pyrolysis unit can be mitigated by bubbling the flue gases through water.
5) Hydrogen Chloride gas (HCL) in the flue stream of a pyrolysis unit can be mitigated by bubbling the flue gases through water.
6) Adding rusty steel wool to the bubbler is an effective way to reduce H2S

[Tplane37]

Acetal (POM)/PVC/ABS

WOW! What a read! It's been said repeatedly throughout the 76 pages of this thread, but outstanding work folks!

To answer one issue that keeps coming up: Finding information in a thread this long. If you look up to, you will see two separate "Search" options. The one in the site's main bar will search the entire site (Or whatever parameters you put in the advanced search feature). Then there is a second search option below that that reads "Search This Thread." I have used the second option multiple times in the past two days as I have read this thread from start to finish, re-reading several posts throughout after utilizing another great search function... Google.

With that said, an brief introduction. I was a Boiler Technician in the United States Navy. I have spent most of my life tinkering with anything that had moving parts, I rebuilt my first engine at about 9 years old. I have spent most of my adult life in the field of industrial plant maintenance, most recently in a steel sand casting foundry as a Millwright and Maintenance man. I have always enjoyed chemistry, fabrication, and finding a use for someone else's junk (more of a "Reuse" aka "Repurpose" than a "Recycle" kind of guy) and I would much rather build something myself than build something of someone else's design... then if it fails, its my fault.

I am primarily focused on diesel fuels (a few hundred gallons per month), secondary on petrol (maybe 50-100 gallons per month, depending on if my diesel truck is running or not). I have been trying to locate feedstock locally for building a processor based on what I have ready access to. I started out looking for WMO, there is some supply, but many local companies already have non-compete contracts with the local refineries... I then looked into WVO, and that is also available in limited supply because it is more common for people to think of doing... Then I remembered a couple YouTube videos about converting plastic to a diesel-like fuel that I stumbled on when I was building my Wood-Gas/Syn-Gas Gasifiers for burning trash (no trash pick-up service at farm)...that lead me here and I am happy with what I have read thus far.

Before this turns into a book, I am in a bio-fuel, industrial community. A lot of companies are paying top dollar for most anything that can be converted into a fuel of some sort. This limits free and cheap feedstock. I was on the phone earlier today with a Plastics Broker for the main plastic recycling company in my area. Prices for #5, #2, and #4 shredded plastic (Separated by PP or PE) is currently priced at US$780 ber Net Ton (2,000 lbs) with a minimum purchase of 20 Net Tons. Cost to much at a time, and not enough gain over the #2 diesel pump (averages out to about US$3.50 per gallon diesel in a highly efficient processor vs. #2 Diesel at US$4.199 per gallon at the pump). "Mixed" plastic (unsorted floor scraps, #3, #6, and #7 plastics) goes for about have of what PP/PE sells for, with the same minimum purchase price, but is likely to contain PVC, PET/PETE, ABS, and POM. However, there was positive information as well....maybe.

Aparently, at alot of the plastic recyclers seminars, there is one thing that they cannot find a use for, and it costs scrapping companies about US$50,000 PER MONTH because of it! They call it "Fluff." Fluff is what Scrap Processors/Automobile Shredders are left with after the vehicles are shredded and all magnetic material is removed, about 30% of every vehicle is "fluff." Fluff it mostly the plastics, carpet, some glass which included the plastic films in laminate glass, and some glass...there is also some rubber from hoses, etc. but rarely includes tires. Auto Shredders have to PAY companies to take the Fluff to landfills. The Plastic Broker and I discussed the pyrolysis procedures done in this thread, he had a couple of key concerns. But said that if we can find a way to deal with a couple of key toxic chemicals, it is likely that not only could we get this fluff for free, it is very likely that the auto shredders would PAY US TO TAKE IT AWAY.

Here are the key concerns that I would like to find a way to neutralize/utilize:

(1) Acetal: Polyoxymethylene ("POM"). This is what the little white/opaque door panel and dash board "push clips" are made from. If even one of these gets into a multi-ton batch of plastic as it is melted in a furnace to be reused as plastic, it puts off a smell similar to the smell of formaldehyde. But looking at it's chemical composition and the fact that the broker flat out said that the smell would "clear the entire plant" but did not incapacitate anyone, I am lead to believe that the fumes are actually a dirty form of methane. ***What gas is formed when POM melts, them cracks? Can it be converted to methanol? Formaldehyde gas is commonly used to decontaminate equipment that have been exposed to bio-agents, it can be neutralized using Ca(OH)2, KOH, or NaOH. Once neutralized, it decomposes to Hexamethylene. But I Have also read that POM creates a gas called Methenamine when exposed to ammonia gas. The use of ammonia gas concerns me because of the posibility of HCl from any PVC's that may be present. How can we deal with whatever gases POM puts off?***

(2) PVC. The issue of the HCl from PVC his has been covered a number of times in this tread. The bubbler takes care of it for the most part. KOH or NaOH dissolved in the bubbler neutralizes it and gives out "waste" fuel an added "kick." Another option is the aluminum which serves a simliar function. I like the Baking Soda concept because it produces CO2, but does it produce enough CO2 to make it SAFE to inject the waste gas stream back into the reactor to displace any oxygen released by any PET/PETE?

(3) ABS. "Fluff" will likely contain ABS plastics, as they are commonly used in automotive interiors. From what little has been discussed in this thread regarding ABS plastics, the biggest concern seems to be Cyanide gas. What are the chances that KOH or NaOH in the bubler can neutralize this as well? If so, Lye may be our best course of action. What are the other ways to neutralize cyanide gas?

(4) It is possible that PET/PETE will be present as well. A CO2 blanket, or posibly even Halon Gas might be a beneficial consideration. And if the auto shredders are paying us to remove the fluff, the cost of Halon could be a determining factor in how much we would charge to remove the Fluff from their yards to keep it out of the landfills?

Most of my posts will not be this long, but I wanted to get a bunch of info out there. It looks like the same basic components are required for the processor, and it is various "add-ons" or "tweaks" that are the factors that vary. I will be building my unit from propane tanks and Schedule 80 pipe for the most part. Before I end this chapter... I mean post... I would like to share one more bit of information.

Propane Tanks are required to be recertified based on a specific schedule. THere are various reasons why a tank can fail certification. Also, most of your propane filling companies are the one's doing the tests and they also accept used tanks for recycling. Typically, these failed tanks are thrown in a pile and left there for quite some time. Locally, I can pick up these tanks for free, if I can beat the scrappers to them. Some tanks will be junk (won't hold pressure), but others will be usable for our purposes, but not for propane. Free is good, and these tanks are made of thinker metal as has been discussed earlier in this thread.

Enough for now!

[Beyond Biodiesel]

Welcome, Tplane37, good to know that you have read the thread, and that you have a technical background, and you are interested in doing pyrolysis to make your own fuel. There are a wide range of substances that can be converted into fuel via pyrolysis. scrap wood, lumber, and sawdust can be pyrolyzed to extract fuel out of it more efficiently than the wood-gas process. News paper can be pyrolyzed to acquire fuel in the same way plastic can.

Your interest in pyrolyzing Polyoxymethylene (POM) has some merit, as it solves a disposal problem of the waste industry.

The conclusion for mitigating toxic emissions while pyrolyzing polymers containing Polyoxymethylene (POM). The two toxic emissions from pyrolyzing Polyoxymethylene (POM) are: Formaldehyde and carbon monoxide (CO).

Mitigating carbon monoxide (CO) emissions are simple. Since carbon monoxide (CO) is flammable, then it is easily mitigated via a burner. So, diverting the exhaust stream from a pyrolysis unit a burner is a simple solution.

Mitigating Formaldehyde is more complex. However, it is soluble in water; therefore, it is reasonable to consider that a simple bubbler might be all that is needed to remove Formaldehyde from the exhaust stream of a pyrolysis unit. Additionally, Formaldehyde is flammable, therefore residues of Formaldehyde in the exhaust stream after the bubbler could be effectively consumed in a burner.

For a more in depth read on the toxic by products of the pyrolysis of Polyoxymethylene (POM) you can click this link:
Toxic by-products of pyrolysis

[imakebiodiesel]

A series of bubblers would be the safest approach to dealing with abs generated cyanide. First a bubbler containing plain water to deal with any pvc generated HCl and then a bubbler containing common bleach (10% soduim hypoclorite) will neutralize the cyanide. However it is important to have the water first as HCl will neutralize the bleach stopping it from dealing with the cyanide and also release chlorine gas.
Pyrolysing unknown mixtures of plastic waste will always be dangerous. While individual known dangerous byproducts can be dealt with it is difficult to know how these various byproducts might react with each other and with the various scrubbers, filters bubblers etc.
Personally, nothing goes into my retort that is not positively identified as PE or PP.

[Tplane37]

Personally, nothing goes into my retort that is not positively identified as PE or PP.

Normally, I would agree 100%. In this instance (Fluff), there are a couple of driving forces for motivation (Getting paid to take it and its going to the landfills), and it is possible to know what plastic might or could end up in the retort by researching and knowing what types of plastics are used in automobiles. Setting a system up to properly handle all types of plastic in a single run, or even multiple runs of mixed plastics if needed could prove pertinent for all users. Especially in a scenario such as with the cyanide: At least 2 bubblers, but the first on MUST be water only, and the second with chlorine bleach (a potential reuse for HCl contaminated water from PVC?), I would consider a third bubbler with KOH in it as the KOH seems to neutralize most anything that would remain.

On the PETE side of things, I have a thought for the control of oxygen in the system. An oxygen sensor from a car/truck wired to a 12v valve for the CO2 purge. It would most likely be a 2 wire O2 sensor, usually when the sensor (which is just a switch) closes its contacts, it send a signal to either the vehicle computer or to the fuel pump of the vehicle, some snsors shut off power to the fuel pump momentarily when they activate, others supply power (signal) to the computer to tell the computer to pulse the fuel pump. Utilizing this signal to open a valve to allow CO2 into the retort might work, but I don't know how sensitive the O2 sensors can be. a 12V power supply would be necessary, but this is already present for the folks using solar to heat their processors.

As for formaldehyde, even though it is combustable, I'd much rather neutralize it as much as possible, but it just flat out stinks, regardless of how dangerous it is to breath, I really don't care if it is actually good for you (which it is not!), I don't want to smell it.

Do we know if formaldehyde, cyanide, and/or HCl can combine with each other in any combination in our systems and at the temperatures we are operating at? What combinations are possible, and how can we either avoid them or neutralize the new element (other than avoiding the type of plastic all together)?

***
Beyond Biodiesel, my next step, now that I have finally read through this tread, is to begin reading through your thread on the Toxic by-products of pyrolysis. Thank you for your efforts it making such a thread available for tailored discussion.

[Tplane37]

Jhanananda

For a more in depth read on the toxic by products of the pyrolysis of Polyoxymethylene (POM) you can click this link:
Toxic by-products of pyrolysis

Is "Jhanananda" a member of this forum as well? If so, is his Username the same here? I am intrigued by his signature:

I have been running various blends of waste oils and unleaded gasoline (Petrol) since Feb, 2007 in a 1983 Chevy G-20 van with a 6.2L diesel V-8 engine, with a Stanadyne Rotary DB2 IP.

I am running a 1985 Chevy C30 dually with a non-emisions 6.2L diesel V-8 engine from a former US Military M1009 (Chevy Blazer). To my knowledge I am also running one of the variants of the mechanical DB2 Injector Pumps. I am curious if and how well various proportions to bio-mass (from plastic) and biodiesel mix, as well as adding #2 pump diesel into the mix work with this engine.

[TheQuietDan]

wood scrap questions

I was wondering what kind of output to input ratio you were getting when you worked over the wood scrap and was the output enough to mess with or more steam and little else?

Thank you in advance for your input.

[xyverster]

oh my...i have been left behind...
anyone know what use nitrogen at pyrolisis process?is it only just to make gone the oxigen from batch?
and about the catalyst i read that zeolite will give some help...where do i should put the catalyst?let the vapor through the catalyst or mix it with waste plastic?
if our waste have water is it a problem?is it really necceserry to remove dirt or water?if we process it to batch what process should i add?

sorry if i ask to much...i work at recyling plastic waste being pellet for reuse...its my uncle factory..just a small factory..
and i want make one factory too that produce fuel..
hope someone can help me, share what u know to guide me...

[imakebiodiesel]

Tplane37, I run my 2 cars on a blend of 70% biodiesel and 30% crude from plastic waste. In my case this is 10% diesel 75% kerosene and 15% petrol.
The resultant mix has exactly the same specific gravity and viscosity as normal commercial diesel. My cars have VW 1.9 engines with bosch rotary pumps and indirect injection. They run very well and start easily on this mix even in cold weather. I dont know if this mix would work well with newer common rail type injection systems. Im told by mechanics who know their stuff that volatiles in a mix such as this would preignite in the injectors and cause damage.

[waterboost]

Oil Samples

We had a good start yesterday (11:30am) and we were still running a batch at 4am.... Far too much patience

I'll be warming up quicker in future...

Our time consuming method allowed us to take samples at different temperatures and we were left with at least 13 noticeably different colours of fuel

We also found that the fuel from poly prop will easily dissolve the waxy crystals from the carrier bag fuel. 100% carrier bags didnt look waxy but v.dark. When the carrier bag fuel cools to 0degrees it goes like runny jelly...

The feedstock on the last run was slightly wet poly prop pellets, strange thing is, to me at least, the water only came out after approx 330 degrees C... along with the first fuel fractions...

[Beyond Biodiesel]

As for formaldehyde, even though it is combustable, I'd much rather neutralize it as much as possible, but it just flat out stinks, regardless of how dangerous it is to breath, I really don't care if it is actually good for you (which it is not!), I don't want to smell it.

Wait until you get a whiff of HCL gas. If you live to tell about it, you will find it will knock you on your butt. So, make sure you have a fully functional bubbler, and a full face respirator on hand before venturing into pyrolyzing fluff.

Do we know if formaldehyde, cyanide, and/or HCl can combine with each other in any combination in our systems and at the temperatures we are operating at? What combinations are possible, and how can we either avoid them or neutralize the new element (other than avoiding the type of plastic all together)?

Might as well add in hydrogen fluoride gas (HF) into the mix. From researching the subject of toxic by-products of pyrolysis all of the major problems are caused by halogenated hydrocarbons, and the toxic and corrosive gasses are just the tip of the iceburg, because down stream from the pyrolysis unit will be formed "super toxins" such as dioxins. So, if you are going to process fluff, then your pyrolysis unit is going to become a super-fund toxic site. So, make friends with your space suit for processing that stuff.

I am with imakebiodiesel. I am just going to stay away from it.

However, I understand the economic incentive, and I appreciate someone wanting to tackle the problem.

I do not happen to believe that the combination of HCL, HF, HCN, plus hydrocarbons is going to result in anything worse than the above. Especially since chlorine is needed to neutralize cyanide. Maybe one bubbler will handle both, but I am all for redundency, especially when dealing with HCL, HF and HCN. You will want to have some high quality gas analyzers on the your operation to monitor your output and protect your operators.

Beyond Biodiesel, my next step, now that I have finally read through this tread, is to begin reading through your thread on the Toxic by-products of pyrolysis. Thank you for your efforts it making such a thread available for tailored discussion.

Thanks, I saw you on the forum. Good to have your contribution there.

Is "Jhanananda" a member of this forum as well? If so, is his Username the same here? I am intrigued by his signature:

Yes, Beyond Biodiesel, Jhananda, Jhanananda, and Jeffrey S. Brooks are all the same guy, me.

I am running a 1985 Chevy C30 dually with a non-emisions 6.2L diesel V-8 engine from a former US Military M1009 (Chevy Blazer). To my knowledge I am also running one of the variants of the mechanical DB2 Injector Pumps. I am curious if and how well various proportions to bio-mass (from plastic) and biodiesel mix, as well as adding #2 pump diesel into the mix work with this engine.

Funny, we are running almost the same vehicle. I have run my 6.2L DD engine in a Chevy g-20 van on a wide range of blends of waste oils plus gasoline for 6 years. Mostly I have run WVO blended with gasoline at 20%, and it runs just fine.

However, burning WMO blends nearly ruined my engine, so I would not recommend WMO for that engine, unless it is distilled. Distilling WMO is why I am here, and why I have a pyrolysis section on my forum. However, I plan to pyrolyze plastics, rubber, scrap wood, cow dung, you name it.