How to turn plastic waste into diesel fuel cheaply

[dippy909]

First Run

Hi

I had my first run yesterday and this is what i got.

(Kindly see the album at the end)

First I had started without a Thermo-couple, which has been rectified today so it was continuously heating no control.
At first Gas started coming through the Bubbler for around 2 hours. I could hear the Liquid in the Reflux splashing back down every few seconds like a cycle. Splash silence, splash. My Pipes did not heat I think there must have been a block in Th Reflux/pipe (the reflux was un-insulated and not heated) . After this time Gas stopped coming from the Bubbler. If there was a block why would gas come i was wondering? Anyway i switched of teh heat when gas reapeared in the Bubbler but not as much as previously. Applied the eat agin and this time I heard Liquid dripping into my Condensor/Seperator.
This lasted half an hour+.
When the reflux quitened along with no Gas in the Bubbler I switched it off.
net result: 1/1/2 Liters of Fuel from 4 kg of feedstock of mixed plastic.

Questions?
1.The Density of the fuel is 0.75 does that make it petrol/ gasoline?
The Fuel was not completley clear, and a viscous dark layer formed at the bottom after settling (is this carbon?)
2. I burned the excess gas from the Bubbler, how could I connect this to my existing Gas cylinder burner that i was using? Or would I need a completly seperate burner?
3. When I opened the retort i found White powdery waxy substance in the pipeline, what was this,I remember reading about some time ago but could not find it in the post its so long now. Kindly guide me.
4. Even when I thought teh process was working well towards the end my pipes/ Condensor hardly got hot, does this indicate blockage?
5. My reflux welding started leaking vapour was seen coming out of it slightly. (just been repaired) but again could this have resulted from backpressure from a block, if I install a Saftey pressure gauge should I place it on top of the Retort? Sorry i know these questions have been asked before.
5. Most importantly the fuel produced and the Gas smell very strong and obnoxious is this a sign of HCI, How can i neutralise this? apart from not using PVC which is impossible with domestic waste in India. A secondary Bubbler can help with the gas but why is the fuel smelling so strong?
6. how do I know if my Catalysts has done its job of aiding cracking? I used a Reflux column containing wire wool at the bottom and broken baked Red Clay at the top?

Apologies for so many questions which I know have been answered along the Forum some where and I am continuously rereading the entire thread taking notes everytime .
Thank you

https://plus.google.com/photos/11239...KmY0Lfw1fTFrwE

[Beyond Biodiesel]

Hi

I had my first run yesterday and this is what i got.

(Kindly see the album at the end)

First I had started without a Thermo-couple, which has been rectified today so it was continuously heating no control.
At first Gas started coming through the Bubbler for around 2 hours. I could hear the Liquid in the Reflux splashing back down every few seconds like a cycle. Splash silence, splash. My Pipes did not heat

If you do not heat your reflux, then this is what you will get. If you heat your reflux, then you will get distillate coming down your condenser.

I think there must have been a block in Th Reflux/pipe (the reflux was un-insulated and not heated) . After this time Gas stopped coming from the Bubbler. If there was a block why would gas come i was wondering?

If you had a block your unit would have blown up.

Anyway i switched of teh heat when gas reapeared in the Bubbler but not as much as previously. Applied the eat agin and this time I heard Liquid dripping into my Condensor/Seperator.
This lasted half an hour+.
When the reflux quitened along with no Gas in the Bubbler I switched it off.
net result: 1/1/2 Liters of Fuel from 4 kg of feedstock of mixed plastic.

Questions?
1.The Density of the fuel is 0.75 does that make it petrol/ gasoline?

Kerosene

The Fuel was not completley clear, and a viscous dark layer formed at the bottom after settling (is this carbon?)

Possibly carbon and un-cracked plastics

2. I burned the excess gas from the Bubbler, how could I connect this to my existing Gas cylinder burner that i was using? Or would I need a completly seperate burner?

I would go with a separate burner that is next to the primary burner.

3. When I opened the retort i found White powdery waxy substance in the pipeline, what was this,I remember reading about some time ago but could not find it in the post its so long now. Kindly guide me.

It is Un-cracked plastics. Did you use a catalyst? Also, what temperature did your retort get to? It sounds like it was not hot enough, or it would be full of dry black carbon.

4. Even when I thought teh process was working well towards the end my pipes/ Condensor hardly got hot, does this indicate blockage?

No, you just have a lot of thermal mass and surface area in your condenser line.

5. My reflux welding started leaking vapour was seen coming out of it slightly. (just been repaired) but again could this have resulted from backpressure from a block,

No, more probably a bad weld.

if I install a Saftey pressure gauge should I place it on top of the Retort? Sorry i know these questions have been asked before.

A pressure gauge on top of the retort is a good idea, but it will have to have a long enough pipe to keep from melting the gauge.

5. Most importantly the fuel produced and the Gas smell very strong and obnoxious is this a sign of HCI,

If your bubbler water and vent have a very sharp offensive smell, then this is probably HCL. If you smell almonds then this is most probably cyanide. HFL is also possible.

To avoid producing either extremely toxic substance your best solution is to make sure you do not have PVC, ABS, or PTFE. The simple test for unsorted plastics is to drop them into water. Whatever floats you can crack, and everything that sinks send off to the landfill.

How can i neutralise this? apart from not using PVC which is impossible with domestic waste in India.

Neutralizing the toxic gasses that are the product of cracking halogenated hydrocarbons is a large subject, which we have discussed at length here. You can find my synopsis on my forum at the following link.
Toxic by-products of pyrolysis

The condensed form of this solution is to make sure you have a bubbler that all of your gasses passes trough, as you did. Make sure there is a continuous flow of fresh water into the bubbler, or otherwise it could become saturated, and/or too corrosive.

The gasses that leave your bubbler should then pass through a burner. If you have such a 2-stage mitigation system for toxic gasses, then you should have them all consumed by the process.

A secondary Bubbler can help with the gas but why is the fuel smelling so strong?

Because cracking halogenated hydrocarbons does not just produce toxic gasses, it also produces distillates with offensive smells that ruin the seals in your injector pump, and produce toxic exhaust from your engine.

6. how do I know if my Catalysts has done its job of aiding cracking? I used a Reflux column containing wire wool at the bottom and broken baked Red Clay at the top?

As stated above, it sounds like your retort never made it to cracking temperatures. Also, if all you were depending upon for cracking was wire wool and broken baked Red Clay (tera cotta) then that might not be enough of an active catalyst. If you cannot buy zeolite catalyst, then simple ash from a fire place, or volcanic ash will work as a catalyst.

Apologies for so many questions which I know have been answered along the Forum some where and I am continuously rereading the entire thread taking notes everytime .
Thank you

https://plus.google.com/photos/11239...KmY0Lfw1fTFrwE

Good to know you read through the thread, and you are reading it again taking notes. Thanks for the photos.

[dippy909]

Dear Beyond Biodiesel,

thank you for the quick response, I will ammend my Reflux ,repair my weld, and will make another trial with monitoring the temperature of the retort and Reflux and report my next run.

Also will do the float test of the plastics for the feedstock

[dippy909]

Just a quick question regarding Catalysts,
I have obtained Zeolite Powder. Can I mix this with the feedstock and what ratio, tried looking through the thread but could not find it.

[Beyond Biodiesel]

Just a quick question regarding Catalysts,
I have obtained Zeolite Powder. Can I mix this with the feedstock and what ratio, tried looking through the thread but could not find it.

Catalyst has been used successfully in several ways here. Some just pour it on top, some use bead catalyst and put it into a wire mesh that is inside the reflux, which is probably more efficient, but the reflux would have to be held at cracking temperatures.

Amount is probably about 1L/55 gallons of plastic. You will have to experiment to find what works best for your unit, and your feed stock.

[Excalibur]

Dippy

Thanks for posting such an informative account of your fuel making experiment, with great pictures too!

Guide here for fuel specific gravities
Does your fuel ignite with a match? (Test carefully please!)
Did it turn to wax once it cooled?

It sounds like there was too much refluxing or the retort temps were too low.
Perhaps the reflux temperature was too low which will cause excessive refluxing. Insulating it will help. An extreme high reflux temperature will make the final product waxy while too low temperature will crack fuel toward lighter fractions. Therefore if you are wanting diesel and the product coming is .75 SG then raise the reflux temperature till the desired weight of fuel is produced.
Temperature probes on the retort and reflux are very helpful. You need to know what's going on there!

2. A separate burner head for excess gases from the bubbler would be the way to go. Ensure there is continuous ignition of the gases else there can be backfiring. I would like to know how you proceed as I am struggling with this issue as well.

4. Pipes and condenser not hot may indicate blockage but more likely is that there isn't much hot gases reaching there. As the gases flow, heat will travel with it.

5. The weld may have been porous for it to leak, perhaps a slag inclusion. Have a real good look at the welds and be sure they are up to standard. A simple pressure test with 2 -3psi pressure on the retort -reflux -condenser array as one, using soapy water on welds and gaskets would be a suggestion.

5. A pressure gauge as a safety warning device is a reasonable precaution. I have one on my diesel condenser. This would alert of any blockage downstream but not upstream.
There was a case of a gauge becoming blocked with plastic earlier on in the forum.

5. The strong smell of cracked fuel is commonly reported. Even cracking waste mineral oil will generate the same smell. Someone suggested recently that running the fuel across limestone might fix it. The information was reportedly from the Shell handbook of Petroleum. Untested tip. Anyone trying this, please advise here if it works.

Once again, thanks for the excellent photos and illustration. You set a good example for others.

[dippy909]

Excalibur

Thankyou for your response.
1. Does your fuel ignite with a match? (Test carefully please!)

Yes its Ignited quite well

2.Did it turn to wax once it cooled?

No it was left out last 3 nights (8 C) no waxing
3.It sounds like there was too much refluxing or the retort temps were too low.

Agree Reflux was just too Cold, Now been insulated.

4. Temperature probes on the retort and reflux are very helpful. You need to know what's going on there!

Installed on both.

5. A separate burner head for excess gases from the bubbler would be the way to go

This will be installed this week, will send send pictures/Details

6. Welds repaired

7. Pressure gauge will Install this week

8. The strong smell of cracked fuel is commonly reported
How could we run the Fuel across Limestone, can we use Calcium Hydroxide?
Also how ?

The unit was modified with a Condensor straight after the Reflux (The idea was to capture more Diesal, Pictures attached) , Thermocouples on the Retort and reflux a Fan blowing Air for the burner. A second bubbler containing Calcium Hydroxide and water (now this I think is wrong please correct me what the second bubbler should contain to reduce toxins in the gas )
I had obtained Zeolite powder but forgot to add it to the feedstock.
(Trying to source the Pellets version so I could put it in the reflux.)

Upon operation thet LAsted 3 1/2 hours
3.5 kg mixed plastic feed , containing 2 PEt bottles.
The oven Peaked at 384 C, The reflux heated very slowly, but acclerated after hitting 100C the maxed at 254 C, was it too much?
A good reaction happened when it hit around 350 C, Liquid flowing in the pipeworks and Condensor, sounds like a stream, but short-lived did not last that long.
When the process stopped no bubbling or activity in the pipeworks it was stopped.
The Gas output was very poor compared to my first run. on/Off no much pressure.
The Retort had 1 inch of solidified wax, Two questions, is this teh result of not reaching a higher cracking temperature, and secondly can I re process this?(Pictures attached).
The Fuel out put seems dissapoiting I was expecting 3.5 liters from 3.5 kg of feestock. Secondly the First condensor gave gold Fuel , SG of 7.75 around 1 liter. But it is not Clear its cloudy, how can I get it clearer
The Second condensor which had air cooled pipes gave dirty Fuel this time and it contained water? Why do you think it is dirty? when inmy last run I had fairly clear fuel from this condensor?
COuld you clarify why water has formed in the process I read in the thread that it can be due to PET but i had only two water bottles.
Both fuels burnt well.

What can I do to tune it for Diesal? , Should I add a third condensor.
Apologies if it is a bit long reply

https://plus.google.com/photos/11239...95646211363393

Thank you

[rozier56]

hi,good photo's,some of my observations re your pic's.
1.your reflux column should be directly connected to your retort,the one inch pipe will badly influence your production capability i.e temp and flow.
2. don't see any water connection to your "condensers"
3. what is the 'S' configuration?
just some of my thoughts.

[rozier56]

Hi guy's,I am having some problems with production rate!
I have a 220kg retort with a 4inch diameter reflux column on top.This reduces to 1inch pipe ,then entering the condenser.No problem holding temp{400-420*c} and easily maintaining production rate at 18lt/hr.Need to increase to approx 3olt/hr.My thought's are to increase diameter of the reflux column and increase cooling capacity.
What do you think?:

[Beyond Biodiesel]

8. The strong smell of cracked fuel is commonly reported
How could we run the Fuel across Limestone, can we use Calcium Hydroxide?
Also how ?

The unit was modified with a Condensor straight after the Reflux (The idea was to capture more Diesal, Pictures attached) , Thermocouples on the Retort and reflux a Fan blowing Air for the burner. A second bubbler containing Calcium Hydroxide and water (now this I think is wrong please correct me what the second bubbler should contain to reduce toxins in the gas )

Calcium carbonate, not hydroxide. The use of adding Calcium carbonate, or other metals into the condensing stream is to reduce acidification of the fuel. Acidification occurs due to the presence of hydrated gases, such as: Hydrogen-sulfide (H2SO4), hydrogen-chloride (HCL), hydrogen-fluoride (HF), etc. all of which are toxic, some of which are readily soluble in water, which the bubbler will take care of, the rest of the hydrated gases are flammable, so a burner will consume the rest.

Iron can do the same thing as calcium carbonate, and it can be introduced easily by stuffing steel wool loosely in your vapor stream after the condenser and before the water bubbler. Plan on it helping to condense out liquids, and you can use your condensate as a bubbler, which will improve the condensation of your vapor stream.

Upon operation thet LAsted 3 1/2 hours
3.5 kg mixed plastic feed , containing 2 PEt bottles.
The oven Peaked at 384 C, The reflux heated very slowly, but acclerated after hitting 100C the maxed at 254 C, was it too much?

Too low

A good reaction happened when it hit around 350 C, Liquid flowing in the pipeworks and Condensor, sounds like a stream, but short-lived did not last that long.
When the process stopped no bubbling or activity in the pipeworks it was stopped.
The Gas output was very poor compared to my first run. on/Off no much pressure.
The Retort had 1 inch of solidified wax, Two questions, is this teh result of not reaching a higher cracking temperature,

Yes. You have to get to 400-425c for efficient cracking.

and secondly can I re process this?(Pictures attached).

Yes, you can leave the uncracked plastics (wax) in the retort and run them again, and again, and again, until the crack.

The Fuel out put seems dissapoiting I was expecting 3.5 liters from 3.5 kg of feestock. Secondly the First condensor gave gold Fuel , SG of 7.75 around 1 liter. But it is not Clear its cloudy, how can I get it clearer
The Second condensor which had air cooled pipes gave dirty Fuel this time and it contained water? Why do you think it is dirty? when inmy last run I had fairly clear fuel from this condensor?

COuld you clarify why water has formed in the process I read in the thread that it can be due to PET but i had only two water bottles.
Both fuels burnt well.[/QUOTE]

The cloudiness might be due to the presence of water in your feed stock, or if you are putting water into your retort to turn to steam, which will drive out the O2 in the retort.

Also, the more you use your pyrolysis unit the more coke will work its way along the pipe work which will contaminate your product. You can filter this out, or use activated charcoal or triple distill your fuel to clean it up.

What can I do to tune it for Diesal? , Should I add a third condensor.
Apologies if it is a bit long reply

https://plus.google.com/photos/11239...95646211363393

Thank you

You can heat your condenser to about 100c to remove petrol, but petrol is valuable as well for thinning thicker fractions, such as motor oil, to diesel fuel sg.

Other observations:

It looks like you have a proper flange, which is good. But, what are you using for a seal on your flange?

2) You condenser line seems to be horizontal. It should lean down toward your condensate trap.

3) The "glass wool" that you are using looks like ordinary "fiber glass" insulation, which is not glass, it is spun plastic and will melt at the temperatures that you will need for cracking. If you cannot find high temperature insulation in your area, such as Kaowool, then you can use charcoal. Charcoal happens to be an excellent insulation, you just have to keep it from getting above 425c, and keep flames away from it.

[Beyond Biodiesel]

Hi guy's,I am having some problems with production rate!
I have a 220kg retort with a 4inch diameter reflux column on top.This reduces to 1inch pipe ,then entering the condenser.No problem holding temp{400-420*c} and easily maintaining production rate at 18lt/hr.

Excellent

Need to increase to approx 3olt/hr.My thought's are to increase diameter of the reflux column and increase cooling capacity.
What do you think?:

When cracking and distilling hydrocarbons it is always best not to be in a hurry. On the other hand it is useful to keep developing your pyrolysis unit until you get what you want.

You could try to increase the diameter of your condenser line to increase flow-rate of vapors, but do you have a pressure gauge on top of your retort, so that you know what the pressure is in there? If you do, and the pressure is not increasing more than a few PSI, then increasing your condenser line diameter will not improve your through put. It would mean you need more heat.

Similarly, increasing the cooling capacity of your condensers will only reduce your losses. So, if you know you have not to little losses, then increasing the flow rate of cooling water to your condensers will not improve your throughput. You could add a second condenser to see if you get any more condensate.

[rozier56]

Thks Beyond,If i increase heat/temp to 480/500*c then i am getting a parrafin wax on cooling.Want to avoid this happening.I do have a pressure gauge on the system and never get higher than half a bar.I will definitley be putting a further cooling condenser in line and also doing away with right angle connections in the gaseous stage. My main reason for improving flow is because a few local farmers want to buy the unit and they need a higher production rate to meet their demands.

[dippy909]

Beyond Biodiesal

It looks like you have a proper flange, which is good. But, what are you using for a seal on your flange?


The Gasket is a Spiral wound type, not sure of the type, rated to 450 C, changing to a metal type Gasket this week as the gasket needs constant changing.


2) You condenser line seems to be horizontal. It should lean down toward your condensate trap.

Modifying this week

3) The "glass wool" that you are using looks like ordinary "fiber glass" insulation, which is not glass, it is spun plastic and will melt at the temperatures that you will need for cracking. If you cannot find high temperature insulation in your area, such as Kaowool, then you can use charcoal. Charcoal happens to be an excellent insulation, you just have to keep it from getting above 425c, and keep flames away from it.

Thanks for this information and yes it started melting today so am changing insulation immediatly, Charcoal sound s interesting but how could it be packed ?


Rozier56 is it possible to see pictures of your unit as it seems a good High capacity unit and I have not found reference of pictures in the thread .
Thank you

[Excalibur]

Excalibur

Thankyou for your response.
1. Does your fuel ignite with a match? (Test carefully please!)

Yes its Ignited quite well

Then it has a volatile content probably just a few percent. By holding the fuel at 80*C or so, the volatiles will evaporate. The real answer is to hold the diesel condenser vessel at the 80* mark while you are making fuel and drive the volatiles downstream to a water quenched condenser. Then those volatiles can be used for another purpose and not lost.

2.Did it turn to wax once it cooled?

No it was left out last 3 nights (8 C) no waxing

Good, the fuel that was plastic has completely cracked. Where it doesn't crack enough it will convert to wax.

3.It sounds like there was too much refluxing or the retort temps were too low.

Agree Reflux was just too Cold, Now been insulated.

4. Temperature probes on the retort and reflux are very helpful. You need to know what's going on there!

Installed on both.

Excellent, the gauges are important. Another good item would be a borosilicate sight glass. It's another tool to aid in the understanding of exactly what is going on inside a retort where you can't see. Fit this where fuel drops into a condenser as a drip rate indicator.

8. The strong smell of cracked fuel is commonly reported
How could we run the Fuel across Limestone, can we use Calcium Hydroxide?
Also how ?

A good question. I had a loan of the book that talked about the limestone but I gave it back. I wonder if coarse limestone in the bubbler water would work? Untested theory caution.

The unit was modified with a Condensor straight after the Reflux (The idea was to capture more Diesal, Pictures attached) , Thermocouples on the Retort and reflux a Fan blowing Air for the burner. A second bubbler containing Calcium Hydroxide and water (now this I think is wrong please correct me what the second bubbler should contain to reduce toxins in the gas )
I had obtained Zeolite powder but forgot to add it to the feedstock.
(Trying to source the Pellets version so I could put it in the reflux.)

Upon operation thet LAsted 3 1/2 hours
3.5 kg mixed plastic feed , containing 2 PEt bottles.
The oven Peaked at 384 C, The reflux heated very slowly, but acclerated after hitting 100C the maxed at 254 C, was it too much?
A good reaction happened when it hit around 350 C, Liquid flowing in the pipeworks and Condensor, sounds like a stream, but short-lived did not last that long.
When the process stopped no bubbling or activity in the pipeworks it was stopped.
The Gas output was very poor compared to my first run. on/Off no much pressure.
The Retort had 1 inch of solidified wax, Two questions, is this teh result of not reaching a higher cracking temperature, and secondly can I re process this?(Pictures attached).
The Fuel out put seems dissapoiting I was expecting 3.5 liters from 3.5 kg of feestock. Secondly the First condensor gave gold Fuel , SG of 7.75 around 1 liter. But it is not Clear its cloudy, how can I get it clearer
The Second condensor which had air cooled pipes gave dirty Fuel this time and it contained water? Why do you think it is dirty? when inmy last run I had fairly clear fuel from this condensor?
COuld you clarify why water has formed in the process I read in the thread that it can be due to PET but i had only two water bottles.
Both fuels burnt well.

What can I do to tune it for Diesal? , Should I add a third condensor.
Apologies if it is a bit long reply
Thank you

Take care the diesel reservoir vessel doesn't overheat, I think 80*C but depending on how hard you choose to drive the volatile content out.

Zeolite is available as BBQ fat absorber and kitty litter. (I haven't used it though)

Retort and reflux are on the low side. Both require tweaking. A retort too low will not get enough cracking while too high will risk boil-over and possibly encourage wax. A reflux vessel that's too low will reflux too much while too high will allow uncracked fuel to escape downstream and make too heavy fuel or become wax.

You would only require a third condenser if you needed to separate a third fuel type.

I suspect the water was in some of the plastic feedstock bottles. If you set the diesel vessel to 80* or even 60*c the water will not live there and will evaporate off downstream. On a water cooled petrol condenser, any water will not evaporate and will need to be manually separated.

[Beyond Biodiesel]

Thks Beyond,If i increase heat/temp to 480/500*c then i am getting a parrafin wax on cooling.Want to avoid this happening.

No need for the higher temperatures. They are probably just causing boil-over.

1]The Gasket is a Spiral wound type, not sure of the type, rated to 450 C, changing to a metal type Gasket this week as the gasket needs constant changing.

3]Thanks for this information and yes it started melting today so am changing insulation immediatly, Charcoal sound s interesting but how could it be packed ?

Charcoal, or any solid granular insulation would need to be put inside of a metal housing. So, for instance, in the case of your reflux column, if you are handy with sheet metal fabrication, or you can hire someone who is, then you could build a clam-shell enclosure for your reflux with a hinge on it, so that it is easily removed for service.

There would have to be a void between 2 layers of sheet metal, an outer layer and an inner layer. The inner layer of sheet metal would be close to your hot object, such as your reflux. The outer layer would be outside, and in between would be a 4" (10cm) void that is filled with charcoal.

You could use your retort to make the charcoal that you need, and extract the volatiles from baking wood into charcoal in the same way you extract, or crack, plastic into diesel fuel. You would use the wood volatiles as fuel in the same way you would use the distillate from your plastic cracking.

4] On your reflux I think it is too far above your retort, and you do not need the narrow pipe. Since you are using standard flanges, then whatever the maximum ID of your flange should be the ID of the reflux, and it would be immediately above your retort, with no pipe in between.

A good question. I had a loan of the book that talked about the limestone but I gave it back. I wonder if coarse limestone in the bubbler water would work? Untested theory caution.

Any limestone (calcium carbonate) will work to neutralize acids, but metals, like steel, aluminum, or copper, will work as well.