How to turn plastic waste into diesel fuel cheaply

[dutchdivco]

Tony

"But, I'm getting 100 miles per gallon!" ,....."Yeah, but its costing you $3000 for a gallon of fuel!"
Or,... "But, I'm only getting 2 miles per gallon!",...."Yeah, but your 'fuel' is water, which is free!"
(Demonstrating why Miles per gallon is only useful as a rough comparison, you really need to figure Dollars (or pounds, euro's, whatever) per mile, in order to calculate economic viability).

Similarly, you CAN'T calculate the econoimic viability of this process, without including the vaporous fuel produced.
As an illustration; I buy plastic for $100 for 150 Lbs.100 divided by 150= .66 per Lb. Takes 9 Lbs to produce 1 gal. of liquid fuel. 9x.66=$5.94 per gallon, NOT economically viable.
BUT, I also get, say,.....200 cubic feet of vaporous fuel, at $.50 a cubic foot market value. (I'm just making up to make a point). So, I'm getting $100 'worth' of vaporous fuel , and 1 gal. of liquid fuel (market price app. $3.50) for a total of $103.50, for an 'investment' of $5.94. And, if I used any of the fuel from the processor, to run the processor, I need to make sure to figure that in my calculations, as well.

As I say, this is just an example, to make the point. Where did you get your estimate of 9Lbs. of plastic, to make a gallon of liquid fuel? Need to come up with a similar estimate of how much vaporous fuel you will get from 9Lbs of plastic, and figure a 'market value', before you can calculate the economic viability of the process. In fact, from my reading here, it seems like the vaporous fuel is a product of the process, and the liquid is more like a by-product, at least in terms of the amounts produced.

Obviously, 'market value' is not going to do you much good, unless you can SELL the vaporous fuel, or USE it.So, things to explore include A) experimenting with catalists and temps, to get the highest yield of liquid fuel, B) using the vaporous fuel to run the processor, C) finding ways to use the vaporous fuel in lieu of other energy sources which you would have to spend $ on. (Such as converting to a propane refigerator, and using a propane powered genset for electricity, and converting a gasoline auto to run on propane). D)Finding a way to super compress the vaporous product, in order to be able to store it in a practical fashion. (Hence, my earlier posts about using an oxygen concentrator).

I also initially focused on the title of this thread, i.e the making of liquid fuel. However, I have since come to realise need to utilise the vaporous fuel, and 'figure' it into the calculations, in order for the whole thing to make sense, economically. Jim

[tony steinke]

logistics

Hey Jim, A thousand thank yous for responding. I agree with everything you are saying. But right now, for me anyway, my plan was to simply harvest the liquid and use the gas to heat the reactor. I live just outside of Chicago where natural gas is dirt cheap and getting cheaper, as exploration technology is improving by leaps and bounds. I also have the ability to lock in currently low prices with long term contracts. I guess the point I'm trying to make here is that logistics is a major component of my equation.

[dutchdivco]

I understand

where your coming from, Tony. Just saying, unfortunately, that to JUST use this process for the liquid fuel, I don't think it comes out as economically viable. I WISH it did, but not sure it does.
And, it may depend on an infinite number of variables.
I am trying to focus on what I see as one of the challenges of making this process economically viable, which is the vaporous fuel; how to 'capitalise' on it, to a maximum amount.
Other challenges involve 'materials handling'; whether to get the material in a condition where it is cheapest, and grind it yourself, or pay a premium, and get it in a form where it is already ground, whether to load it by vacuuming it into the reactor, or load it in bales, etc.
Heating from inside the reactor, or externally, etc.
I therefore respectfully disagree with those who say we need one design; I believe we need what we currently have; many different approaches, based on the resources available, and which will, in time refine things somewhat.
So, I like the 'open source' approach, and the 'brainstorming' we are doing.
I think we are still at the point of asking questions; answers are still a long way off. Jim

[imakebiodiesel]

There is no doubt that fully sorted, shredded, and baled waste plastic is an expensive commodity. If this technology is going to be viable for small scale users then we must intercept the waste plastic earlier in the processing stream. We have one big advantage, we are among the first people to start looking for sources of suitable waste plastic.
I have found that one of the best sources of polyethylene is the 20 litre containers that a huge number of liquid products are sold in, oils, detergents, building additives etc. Each one of these weighs half a kilo. I know of at least one local business that has to dispose of over a hundred of these a month.
I have constructed a simple plywood box with two electric chainsaws, arranged crosswise. The 20 litre containers are put in the top of the box and come out quartered at the bottom. The quarters then can be loaded into a reactor , packed tightly together and any leftover space can be packed with smaller shredded waste plastic. This way i have been able to pack 50 kilos of plastic into my new reactor which is still quite compact.
Collecting and processing waste can be as difficult or as easy as you make it. Ive been making all of my own fuel from waste veg oil for six years now and find it very little hassle. In 2 years time i intend to be making most of my fuel from waste plastic.

[dutchdivco]

Great

I agree re: intercepting the plastic 'earlier'in the pipeline, and your solution is simple and elegant. I FEAR this will be somewhat like WVO; a 'lot' of people will hear about this, with the result that it will become harder for us to find suitable product, and sources which may now be 'happy' to have us haul it off for free, will begin to expect to be paid for it.

And, probably 1 in 50 of those who get into it, will stay very long, (just like WVO). ALL they will do is make it tougher for those who really invest of themselves in it.

And then, the 'TAXMAN' will hear about it, and come around with forms, and hand out. Or, worse, some numbnuts will blow himself and half his neighborhood up, because he's disregarding safety to do it on the cheap, and regulations will be passed, limiting it to big corps.

But again, a great, simple, elegant way to deal with the plastic! Jim

[imakebiodiesel]

You are right about wvo, it has become much harder to get free in the last couple of years. Thats why Im looking into this technology.
It will be a long time before we will have to pay for waste plastic. Currently businesses here in EU must pay 260 euro per tonne to have their plastic waste collected. Legislation is coming that will reduce plastic going into landfill and by 2020 no plastic at all will be allowed into landfill. The cost of recycling will rise sharply.
The tax system is already in place, I pay 44c per litre of biodiesel that I make and the new fuel will attract 48c per litre because technically its a fossil fuel. It is still well worth making my own fuel because ordinary diesel costs 152cents per litre.
Safety is a major issue. Plastic pyrolysers are potentially dangerous and if someone blows themselves up it could have serious consequences for everyone else who are doing it safely.

[blackchisel97]

Hello everyone,
This is great thread I'm still reading for the second time from the beginning and sorting all details in my head. I found one patent and site (Japanese) related to this process. Their units are nice but small table top model capable of processing 1kg at the time costs now $12,700. However they posted some data of raw fuel/ oil ratios with certain types of plastics. - Š”Ž®‰ïŽÐƒuƒŒƒXƒg�|�»•i�î•ñ�@ŽÀŒ±ƒf�[ƒ^�@”pƒvƒ‰ƒXƒ`ƒbƒN–û‰»‘•’u�|
Some are in 90% range and that would be the best shot imo.

This is their website translated - Š”Ž®‰ïŽÐƒuƒŒƒXƒg�|�»•i�î•ñ�@”pƒvƒ‰ƒXƒ`ƒbƒN–û‰»‘•’u �|

And patents - USP Appln 2009117015
KR20090031685
LIQUEFYING APPARATUS

JP 2008195821
SMALL-SIZED LIQUEFACTION EQUIPMENT

They use double condenser or three stage fractal column for separation, beside and auger feed, preheating stage etc. I like the idea of agitator inside the reactor helping to keep melting mass and prevent spot overheating. especially if one chooses to use bottom oil burner.
I was also thinking about catalyst which could be added to the reactor not after. I found this recipe -
mixing the following ingredients in the proportion indicated there against faujasite zeolite - 5-35 wt %; pseudoboehmite alumina - 10-40 wt %; polyammonium silicate - 1-10 wt %; kaolin clay - 15-60wt %; - milling said ingredients and making a slurry using water, - spray drying said slurry to micro-spheres, and - calcining said micro-spheres at 500°C for 1 hour to obtain the catalyst. What about using pumice as a substrate to be covered with catalyst?
When I thing about the reactor vessel I would add metal shield behind the heating elements to save energy (radiant heat effect). I was also thinking about shredder - small carbide tipped (even old) saw blades on two shafts, spaced and rotating slow (to avoid heat and melting) with help of planetary gear (relatively small motor could be utilized).
I would love and will build this. There is still plenty of plastic going to the landfill in this area despite attempts to promote recycling.

Now I'll go back to reading and drawing.
Thanks for great inspiration

V

[tony steinke]

Hey V, could you elaborate a bit more on your idea for a shredder, as I can't move forward until I have a solution to consolidating my post consumer waste plastic. I purchased 40 brand new 7 1/4" 24 tooth carbide tipped saw blades for the unbelievable price of $56.00. These would normally retail for about $168.00. If I like your design better and it requires more blades, I want to purchase them while they are still on sale.Thanks, Tony

[tony steinke]

I've got to much time on my hands

I don't know how many of you are familiar with the 80's musical group called Styx, but the song title above was definitely relevant today. For those of you who have access to already shredded plastic or lumps of plastic, (as they were previously called ) for free or reasonably priced, count your blessings. Today, I took ten- 1 gallon milk jugs, and smashed them into a 5 gallon container simulating a reactor. They fit okay. To give you a yardstick, the maximum pe that will fit into this size container is approx. 40 lbs. This is based on pe weighing approx. 57 lbs. per cubic ft. I then took them out and cut them up into small pieces less than 1 inch square. To my surprise, these 10 jugs now fit into a reactor that was under 1 gallon in size. I then melted this down to a fully formed solid, or lump. It measured just 6" in diameter and an 1 1/2" thick. Next, I weighed what originally would have required a 5 gallon reactor; it was about 2 lbs. This, I figure, would have produced about 1 litre of liquid fuel. Like I said, the title of the song was very relevant today.

[blackchisel97]

Hey V, could you elaborate a bit more on your idea for a shredder, as I can't move forward until I have a solution to consolidating my post consumer waste plastic. I purchased 40 brand new 7 1/4" 24 tooth carbide tipped saw blades for the unbelievable price of $56.00. These would normally retail for about $168.00. If I like your design better and it requires more blades, I want to purchase them while they are still on sale.Thanks, Tony

Hi Tony,

I was looking through numerous commercial designs but I firmly believe that good device doesn't have to be neither sophisticated nor expensive. I have built once roller with several blades spaced together for cutting shallow groves in particle board (for commercial display boards). This is similar but I think it will require less torque. Most plastics will melt and clog or jam fast rotating tools so this has to be done with low speed. I would use two threaded pieces as vertical shafts and fasten blades with spacers in between so when assembled, opposing blades will go between. The distance between both rollers (saw tips) will need to be adjusted for best performance, perhaps more than 50%. Threaded rod has to be the same as any saw, where blade tightens by encountering resistance, so they won't loosen up during operation. You need both rollers to rotate in opposite direction. I was thinking about planetary gear because of low roller speed and high torque which could be obtained from 1/2HP motor say 1250rpm. One more thing, You may need to make two sets of combs (they could be a separate pieces attached inside the chute and going from the chute angular to the roller, between blades. They will keep material from rotating around.
Now, the gear box; one small on the motor shaft, one big interlocking with gear on one roller. Both rollers connected via their gears together. CW motion of motor shaft will cause CCW of large wheel and CW of one roller and CCW of second roller. I hope it isn't too complicated (my explanation).

These are examples of commercial knives - Cutters For Shredder - KUN SHENG MACHINE CO.,LTD.

and one type of a shredder - Plastic Shredders This is 10HP machine but with those rollers it can crush almost anything. Most Poly vinyls need to be cut while polycarbonate will break quite easy.

on this pic you can see inside the chute with "combs" on each side - http://i01.i.aliimg.com/photo/v0/262...c_shredder.jpg

this is similar concept - http://image.made-in-china.com/2f0j0...c-Shredder.jpg

http://i.ytimg.com/vi/btf5YT-VQTM/0.jpg

http://i.ytimg.com/vi/btf5YT-VQTM/0.jpg

http://i01.i.aliimg.com/photo/v0/448...er_Machine.jpg

This is four roller - http://recyclingmachineryinternation...r-rotor-01.jpg

I think that blade version will work just fine. Originally I was thinking of using smaller blades but 7" maybe good or even better.

Those are just my ideas. I hope they may help.

Vtech

[blackchisel97]

In the second post back when I showed the catalyst recipe I forgot to add that coal was also added to the reactor for the same purpose. However, they didn't provide any details or amount.

V

[blackchisel97]

Zeolites

It seems that Zeolites are most common material use as catalyst among pyrolysis processing plants. I found this link with some more info about different types. I hope it will be useful - Our Products.
What I have in mind is small unit capable of processing 20 - 50kg of plastic waste and utilizing same product as heating burner fuel (with gas boost).
If I could use this oil in my furnace to heat entire house for $160 instead of $1600. Small diesel such as Lister with generator could work perfect as a back up plus few HP of mechanical work, if needed. Sorry, this is probably very obvious but I'm just thinking out loud

I also checked one place running PVC through as well and they use water bubblers to separate chlorine gas (it becomes hydrochloric acid in the bubbler).

Quote form one plant - Natural gas is only used on start-up to heat the reactor. Once the processor is running, the reactor is heated with its own off-gases. That's what I was thinking..
V

[dutchdivco]

Don't hesitate, or apologise

For stating the obvious! I just had a "DOH!" moment, rading the post about melting the plastic, (at a temp way lower than necessary to cause Pyrolisis).
THATS another way to deal with the plastic, rather than shredding it, and I had completely forgotten that!
When Jetsis was working on the fed mechanism, he was heating it up high enough to cause pyrolisis, WHILE it was in the drill bit (auger) feed mechanism, and so I think I developed a blind spot, and it didn't occur to me you could melt it at low temp, and let it cool in a kind of mold, that woulkd leave it an ideal shape for loading into the reactor. So, thats another way to go. And if, as it seems, there is a LOT of vaporous gas produced by this process, (in comparison to the amount of liquid fuels produced)even when you get the recipe just right, it may be that using said gas, for this first stage melting, would be a practical way of 'using up' this vaporous gas.

Possibly, while running one load thru the reactor, could be using some of that vaporous gas being produced, to 'first stage' prep the material that will be the next load? Anyway, certainly gives me something additioal to think about!

The description/ideas on the shredders are good, too. A lot will depend on the exact nature of the material when you get it; if you find a relible consistent source where the plastic is in one form, you can as Imake said, design a shredder with 2 chainsaws or whatever, specifically to deal with the material. On the other hand, if you get the material in a different form, or if you get it in various different forms, need a more general kind of shredder, where you can basically throw in anything that will fit in the opening, and it will chop it up. Something like the tree branch shredders only smaller.

The source I was looking at on craigslist, from the pictures appeared to be scraps of material, that had originally been in sheets or rolls, and apeared at least, to be fairly soft; it looked similar to what they use as carpet underlayment.Quite different than milk or liquid containers, which are hard/stiff.

Anyway, still more for me to think about, so again; don't hesitate to 'state the obvious', or apologise for going into what you think is too much detail. Whats obvious to you, might well be something which hasn't occurred to someone else! LOL Jim

[blackchisel97]

Thank you Jim
This is a bit new field for me. My father was an inventor, chemist, dealing with fuels , additives and refining processes. Unfortunately, I can no longer ask him for advice and at that time I was a college student. Quite long ago, lol.
Preheating process was also described in Japanese patent. Actually it was done in two stages before entering reactor vessel. I could guess more than read from Japanese patent but there is couple detailed diagrams including one pic of vessel equipped with bottom agitator. This would speed up melting and keep substrate in motion. It could be probably powered by wipers assembly with extended shaft. Similar idea like in commercial dough mixers. I'm trying to work (in my head and on the paper) the device heated by oil instead of electricity. Local rates are $0.1/kW. Additional use of processed gas could also lower the oil intake.
I'll keep on searching. We have already enough data but it is nice to learn things which were already tried, tested and proven by others, rather than spending time to re discover the light bulb.

Thanks
V

[tony steinke]

Thank you Vtech, for your valued ideas. I am determined to lick this problem before we have another major shock to the world oil supply, which could be soon. There is a 1000 lbs used baler for sale, not too far from my home. If I can pick it up for cheap, this will be the cat's meow.