How to turn plastic waste into diesel fuel cheaply

[Excalibur]

BBD - "All you need to do is get the viscosity / specific gravity close to that of diesel fuel and you will be able to run your fuel blend on any diesel engine." (don't know how to paste two quotes into one post)

Hi guys. Can anyone with experience in blending diesel fuel help me out on this one?

I have access to a few hundred litres of dirty, oily kerosene per week for little effort. It is used as degreaser for parts cleaning so there will be some contaminants (watch out for TCE right BBD!) but typically grease, oil, road grime etc. I got a copy of the MSDS for the new product which states the boiling range is 150C-280C with a flash point > 61.5C and a kinematic viscosity < 7cSt @ 40C.

It would appear that if I clean it up and blend oil into it to get the viscosity right I can use it in my work trucks.

Excalibur - given the flash point is fairly high I shouldn't have the issues you mentioned above right? Our temperatures here average 10-30C with some colder and hotter days. I have a couple of 10 year old Isuzu 2 tonners, a new Isuzu 5 tonner and one 10 year old Isuzu 10 tonner.

BBD - Should I stick to a standard lube oil for the blending? I figured if I had access to heavy gear oil or even grease I could add less of it to the kero to match the viscosity. But I wonder if the kero and grease will stay blended or 'fall out' like bitumen does? Would long, 'fluffy' grease molecules be ok going through the engines? Some greases have soap (?) or other additives in them, would that be a concern?

Col, good find with the kerosene! With the boiling point range it has it will be very stable in my opinion. Compare that to what I've been blending with, which has a boiling point of 40'c. I dream of finding kero in the quantity you have access to.
If you were to centrifuge the kero, that would be the best thing. That fuel may not clean up clear and transparent but it most likely won't matter too much. It depends on what it's contaminated with. Filtering alone often doesn't remove the black color waste often is. If it's centrifuged/filter to 1 micron, it's a good as it needs to be however if there's lots and lots of free-carbon in the fuel it can soot the injectors. So really if it doesn't work because it soots injectors then the solution is to distill it. That would require heating to 150'c -280'c range and condensing the vapors.
So, having done blending for about 10years, I'm confident it's worth trying and I give it a high probability of success. A lot has been learnt about what you can get away with and it's still work in progress to some degree.
I don't know about grease as a blend component. Yes, it's said to have wax as a carrier for the lubricant. Start with oils, and the cleaner and lighter viscosity the better.
Perhaps hop over to BBDs' forum for lots of discussion, ideas, points of view, etc on blending.

[Col]

Blending diesel without cracking anything

Yes, it will lower the flash point but that's not always going to present too much of a problem. What's more likely to be an issue is the restarting of the engine once it's shutdown hot and left for 5minutes+. It appears heat-soak can create bubbles in the IP and injectors.
There's a number of if's and but's, but much would depend on the boiling point of the gasoline, climate, vehicle design etc. Recently I tested my local gasoline boiling point and found it was 40'c while the US gasoline is 80'c. This is one reason why experiences can vary.

BBD - "All you need to do is get the viscosity / specific gravity close to that of diesel fuel and you will be able to run your fuel blend on any diesel engine." (don't know how to paste two quotes into one post)

Hi guys. Can anyone with experience in blending diesel fuel help me out on this one?

I have access to a few hundred litres of dirty, oily kerosene per week for little effort. It is used as degreaser for parts cleaning so there will be some contaminants (watch out for TCE right BBD!) but typically grease, oil, road grime etc. I got a copy of the MSDS for the new product which states the boiling range is 150C-280C with a flash point > 61.5C and a kinematic viscosity < 7cSt @ 40C.

It would appear that if I clean it up and blend oil into it to get the viscosity right I can use it in my work trucks.

Excalibur - given the flash point is fairly high I shouldn't have the issues you mentioned above right? Our temperatures here average 10-30C with some colder and hotter days. I have a couple of 10 year old Isuzu 2 tonners, a new Isuzu 5 tonner and one 10 year old Isuzu 10 tonner.

BBD - Should I stick to a standard lube oil for the blending? I figured if I had access to heavy gear oil or even grease I could add less of it to the kero to match the viscosity. But I wonder if the kero and grease will stay blended or 'fall out' like bitumen does? Would long, 'fluffy' grease molecules be ok going through the engines? Some greases have soap (?) or other additives in them, would that be a concern?

Thanks heaps.
Col.

[lowriderzzz]

I have a 23L retort that I boil 19L of WMO in and I use a coil from an electric stove for a hot plate, 2 band heaters for the sides and 1 line wrap heater for the top and refluxing zone. All of the heaters are designed for well above 425c. It takes about 1500 watts to complete distilling of 19L of WMO in a 4 hour run. I use PID controllers and variacs to control all of the heaters.

Ok, I assume that as a YES to my question.

Thank you

[Beyond Biodiesel]

well but you said your test unit is for 100 grams of fuel - that is less than mine ( 8 litters volume retort ). Do you think electric heating only will provide with enough heat for such a size ?

I have a 23L retort that I boil 19L of WMO in and I use a coil from an electric stove for a hot plate, 2 band heaters for the sides and 1 line wrap heater for the top and refluxing zone. All of the heaters are designed for well above 425c. It takes about 1500 watts to complete distilling of 19L of WMO in a 4 hour run. I use PID controllers and variacs to control all of the heaters.

[lowriderzzz]

lowriderzzz



I switched to an electric kiln to heat my retort mainly because I can control the temperature with a PID controller. I set the retort in the kiln and hook the thermocouple that's welded to the retort into the PID controller and wait until it gets up to temperature. I only use electric for my small scale tests currently.

well but you said your test unit is for 100 grams of fuel - that is less than mine ( 8 litters volume retort ). Do you think electric heating only will provide with enough heat for such a size ?

[mjohnson1]

lowriderzzz

I have use a propane stove that's almost identical to the picture you provided. It had no problem getting the retort up to 450C with proper insulation.

I got real tired of babysitting the propane burner and having to monitor it all the time in case the wind blew it out.

I switched to an electric kiln to heat my retort mainly because I can control the temperature with a PID controller. I set the retort in the kiln and hook the thermocouple that's welded to the retort into the PID controller and wait until it gets up to temperature. I only use electric for my small scale tests currently.

[lowriderzzz]

temperature - will it be enought

Quick question.Do you think it will be enough to reach 450C with a gas burner like this for my experimental retort from old fire extinguisher.

I'm thinking of putting around it some 1440W heating coils too. I dont know if it will be enought to make 450C temperature with them.

Which method you suppose will be better ? Or perhaps a combination of both ?

What do you suggest ?

[lowriderzzz]

For HDPE and PP they come out in 1cmX5mm size. Pretty small. Yes it would work great for continious feeding. For plastic bags it doesn't work as well and requires shredding a 2nd time. I mainly shred HDPE buckets i get for free now.

nice - thanks

[mjohnson1]

How big the shredder pieces come out with this type of shredder. We had those in much bigger scale in the incinerator at cruise ships I used to work on, however it didn't cut the waste to small pieces but just sort of smash and compressing it, making it less bulky.

Do you this one will be suitable for cutting flexible plastic into small pieces that could be further used for continuous feeding?

For HDPE and PP they come out in 1cmX5mm size. Pretty small. Yes it would work great for continious feeding. For plastic bags it doesn't work as well and requires shredding a 2nd time. I mainly shred HDPE buckets i get for free now.

[Beyond Biodiesel]

Is the jury back on the cyclone concept? Is anyone actually using a cyclone currently?

I do not recall the topic coming up, but Chevron Research used cyclone separators a great deal for separating the catalyst from the flue-stream. It was very efficient, and could operate at 1200F (600c).

I have also used cyclone separators for separating animal fat and water from my WVO stream when pumping out a storage tank. While it is not super efficient, it definitely works, and it works at high velocity, so that when I pumped from a storage tank, my transfer pump pumped the WVO through a cyclone separator on its way to my mobile storage tank. It worked great.

...When pyrolysing plastic the feedstock is liquid and little or no ash or dust is produced. I have never needed to clean out the top of my retort or pipework after more than 70 batches of plastic.
I dont know if this is the same for WMO as I have only done a couple of small batches but Im sure BB or someone else can comment on that...

Good to know that you are not finding much coke in your plastic pyrolysis unit.

I am still developing my WMO distillation system, so it is not at all a regular process that I run at this time; however, I have run 10 to 20 batches and have not seen the need to clean out anything yet. There is a buildup of coke on the inside walls of my retort, which I expect to have to scrape off one of these days. The pipe work has a thin coat on it, but it has not posed a threat to plugging yet.

[imakebiodiesel]

The cyclone separator is for removing dust particles and is used in syngas generators because there is a considerable amount of ash and dust carried along in the gas. When pyrolysing plastic the feedstock is liquid and little or no ash or dust is produced. I have never needed to clean out the top of my retort or pipework after more than 70 batches of plastic.
I dont know if this is the same for WMO as I have only done a couple of small batches but Im sure BB or someone else can comment on that.

Ive come across a book that will be of interest to anyone considering building a granulator/shredder for waste plastics. Its called Small Scale Waste Plastic Recycling by Jon Vogler. It it aimed at projects in the developing world and takes a very low tech approach. There is a chapter on building your own granulator/shredder with drawings and text. Two models are explained and could be constructed by a workshop with basic welding and fabrication facilities.
The book is available on line, do a search for Pla-vogler_ebook.pdf and you should find it.

[lowriderzzz]

fibuslitero



I always feed plastic using a pair of plastic tongs and unplug/shut off the breaker when removing stuck plastic.

How big the shredder pieces come out with this type of shredder. We had those in much bigger scale in the incinerator at cruise ships I used to work on, however it didn't cut the waste to small pieces but just sort of smash and compressing it, making it less bulky.

Do you this one will be suitable for cutting flexible plastic into small pieces that could be further used for continuous feeding?

[Col]

Cyclone

Is the jury back on the cyclone concept? Is anyone actually using a cyclone currently?

[mjohnson1]

fibuslitero

I did buy the shredder online from a gentleman named Marcus. He's from germany. If you search for mini shredder or diy shredder on Google you'll be able to find his Facebook page. I hooked it up to a 3 phase motor and had to use a phase converter for the 220V single phase power in the garage.

I always feed plastic using a pair of plastic tongs and unplug/shut off the breaker when removing stuck plastic.

wrtner

I don't run this indoors always outside a minimum of 30 feet away from any flammable objects with water and a fire extinguisher nearby.

[wrtner]

I am not follwing this thread closely and so, this may be redundant but....

The pics make it look as if you are runnng equipment indoors. If the gear leaks, possibly as a result of a gap caused by thermal expansion, you may get gases which are :

1. deadly poisonous and/or

2. highly inflammable or explosive.

If you must function indoors, it would be good to have a couple of those 15" office fans blowing air from inside, through the room, to outside.