How to turn plastic waste into diesel fuel cheaply

[Excalibur]

With my last run, I used either diesel or non-condensable gases, but not both at the same time. When running on diesel, I temporaily store the gases in a gasjar. Flame-outs can be and were a problem with earlier iterations but the turk burner head has some steel plates inside which glow red hot. Indeed the turk housing and feedpipe often are red hot too. This red hot steel creates a natural ignition for the gas and I had the gas burning for a couple of hours continuous. The diesel reservoir target was 120*C , downstream a gasoline trap followed by a (unheated) bubbler. It was a good amount of usable gas however I discovered that I 'cracked the product too much' and the diesel was a bit light. So next run I'll be using a higher reflux temp so may not get the sheer volume amount of non-condensables. We'll have to wait and see...

Yes, if there is a flame-out, there can be a loud bang as the gas suddenly ignites. It is a bit "hair raising" and it did blow the forced draft fan off the inlet more than once. When the flame has to be reduced to curb retort temps, there is much more of a chance of flame-out.

Later mods, I thought I'd use a LPG gas appliance method of initial ignition. They use a thermocouple to sense the presence of flame plus a simple electronic spark ignitor. Look at gas fired water heaters, central heating units, etc.

[curlyrocks]

After more thought, curlyrocks, I think you are onto something. Since bromine scavenges lead, and PC board recycling will have traces of lead on the PCBs, then bromine in the pyrolized PCBs will scavenge the traces of lead and form Lead(II) bromide (PbBr2). And, since lead(II) bromide (PbBr2) has a melting point of 703.4°F (373°C), and a boiling point of 1,681°F (916°C), then Lead(II) bromide (PbBr2) will be left behind preferentially in the retort, thus the ash and coke in the retort will have fairly high concentrations of Lead(II) bromide (PbBr2). All the PC board recycler has to do is develop a relationship with a brominide plastics manufacturer to sell the Lead(II) bromide (PbBr2) to, which might be more valuable to the brominide plastics manufacturer than diesel fuel.

Thx for the advice again BB. I was wondering what to do with it, but I am planning on doing this for the purposes of recycling the copper and was looking for a practical use for the plastic, this now looks like I may be able to do all 3, separate the plastic from the metal, make a fuel either a gas fuel to be burned right away for electricity or made to a liquid later for fuel, and do something safe with the bromine, I think I'm too far from a major source of computer component manufacturers to make much money off of it but it would be good to do both in principle and for the environment and knowing that more of it will be trapped in the retort rather than in the finished fuel or off gasses is good to hear.

[Babataku]

With my last run, I used either diesel or non-condensable gases, but not both at the same time. When running on diesel, I temporaily store the gases in a gasjar. Flame-outs can be and were a problem with earlier iterations but the turk burner head has some steel plates inside which glow red hot. Indeed the turk housing and feedpipe often are red hot too. This red hot steel creates a natural ignition for the gas and I had the gas burning for a couple of hours continuous. The diesel reservoir target was 120*C , downstream a gasoline trap followed by a (unheated) bubbler. It was a good amount of usable gas however I discovered that I 'cracked the product too much' and the diesel was a bit light. So next run I'll be using a higher reflux temp so may not get the sheer volume amount of non-condensables. We'll have to wait and see...

Yes, if there is a flame-out, there can be a loud bang as the gas suddenly ignites. It is a bit "hair raising" and it did blow the forced draft fan off the inlet more than once. When the flame has to be reduced to curb retort temps, there is much more of a chance of flame-out.

Later mods, I thought I'd use a LPG gas appliance method of initial ignition. They use a thermocouple to sense the presence of flame plus a simple electronic spark ignitor. Look at gas fired water heaters, central heating units, etc.

Many Thanks. I will see if i can get one of those. Its a shame to waste all that heat and since my new outfit will be of a bigger size it means the flare will also need to be huge and burning all that excess will produce a big flame.

will keep you update once im done

[Beyond Biodiesel]

Thx for the advice again BB. I was wondering what to do with it, but I am planning on doing this for the purposes of recycling the copper and was looking for a practical use for the plastic, this now looks like I may be able to do all 3, separate the plastic from the metal, make a fuel either a gas fuel to be burned right away for electricity or made to a liquid later for fuel, and do something safe with the bromine, I think I'm too far from a major source of computer component manufacturers to make much money off of it but it would be good to do both in principle and for the environment and knowing that more of it will be trapped in the retort rather than in the finished fuel or off gasses is good to hear.

It might be that the Lead(II) bromide (PbBr2) is not going to be a huge amount, so you could conceivably store it up in some kind of container until you have enough to make it worth while for a brominide plastics manufacturer to purchase.

Another angle is, if enough people here recycle brominide plastics into fuel, then it could be a useful positive media for the brominide plastics manufacturer to create a venue for recycling Lead(II) bromide (PbBr2).

I look forward to monitoring your progress.

[rozier56]

Hi folks, please note this is a picture of my finished plant.Note that we are using lpg gas as our heat source.The retort is a 220kg capacity plant going through a retort system into a triple tree condenser,product collected in first tank,gas then collected and pushed through attached water bubbler and returned to retort for burn-off.My question remains at what temps are you burning at and at what point are your measurements taken?I wish to maximise my system. diesel plant 004.jpg

[dippy909]

Unburnt Hydrocarbons

I have been having trials with my new 200 liter unit (will post pictures soon).

Have been having problems with fuel output and unburnt Hydrocarbons.

(Feedstock mostly Hdpe/LDPE)
Reflux was increased to 4 feet with a series of baffles and catalyst (red Clay).

Fuel out put wasfeedstock was around 100kg
First Condensor: Duel was dark brow/Yellow Clear 20 liters, SG was 0.85
Second condensor (After water cooling) out put was dark brown/yellow clear 9 liters SG was 0.75. I thought this was good as petrol, put it in one of my cars and the engine was missing badly.

Could this be due to pre ignition? too low Octane? kindly help me clarify the problem.

Also the process took ages 2 hours to heat upto 250 C but peaked at 380C.(after 4 hours)
The Gas slowed down after 6 hours and temperature at the water Condensor inlet reduced considerbly, so I thought no vapour flowing so switched the process off.
When i opened the retort i found nearly 30 kg of unburnt yellowy waxy Hydrocarbons, was expecting black Char.
Could somebody clarify why this unburnt?
Can it be due to too low a retort temperature, can the Reflux now be Too big?
Its puzzling me

[Beyond Biodiesel]

Hi folks, please note this is a picture of my finished plant.Note that we are using lpg gas as our heat source.The retort is a 220kg capacity plant going through a retort system into a triple tree condenser,product collected in first tank,gas then collected and pushed through attached water bubbler and returned to retort for burn-off.

Hi rozier56, thanks for the photo. Your retort looks very professional, but your condenser looks light to me.

My question remains at what temps are you burning at and at what point are your measurements taken?I wish to maximise my system.

Cracking temp is 425c. I have condensers at 300c, 200c, 100c , ambient, and 0c. I measure all the temperature at all of those points along the stream from retort to the last condenser to make sure the vapor stream is responding to my condensers.

I have been having trials with my new 200 liter unit (will post pictures soon).

Have been having problems with fuel output and unburnt Hydrocarbons.

(Feedstock mostly Hdpe/LDPE)
Reflux was increased to 4 feet with a series of baffles and catalyst (red Clay).

Fuel out put wasfeedstock was around 100kg
First Condensor: Duel was dark brow/Yellow Clear 20 liters, SG was 0.85

This is diesel fuel.

Second condensor (After water cooling) out put was dark brown/yellow clear 9 liters SG was 0.75. I thought this was good as petrol, put it in one of my cars and the engine was missing badly. Could this be due to pre ignition? too low Octane? kindly help me clarify the problem.

That is because it is sg of kerosene, not gasoline

Also the process took ages 2 hours to heat upto 250 C but peaked at 380C.(after 4 hours)
The Gas slowed down after 6 hours and temperature at the water Condensor inlet reduced considerbly, so I thought no vapour flowing so switched the process off.
When i opened the retort i found nearly 30 kg of unburnt yellowy waxy Hydrocarbons, was expecting black Char.
Could somebody clarify why this unburnt?
Can it be due to too low a retort temperature, can the Reflux now be Too big?
Its puzzling me

It takes hours to complete a cracking run, and you did not get to cracking temperature. Cracking temperature is 425c.

[Babataku]

Insufficient heat

I have been having trials with my new 200 liter unit (will post pictures soon).

Have been having problems with fuel output and unburnt Hydrocarbons.

(Feedstock mostly Hdpe/LDPE)
Reflux was increased to 4 feet with a series of baffles and catalyst (red Clay).

Fuel out put wasfeedstock was around 100kg
First Condensor: Duel was dark brow/Yellow Clear 20 liters, SG was 0.85
Second condensor (After water cooling) out put was dark brown/yellow clear 9 liters SG was 0.75. I thought this was good as petrol, put it in one of my cars and the engine was missing badly.

Could this be due to pre ignition? too low Octane? kindly help me clarify the problem.

Also the process took ages 2 hours to heat upto 250 C but peaked at 380C.(after 4 hours)
The Gas slowed down after 6 hours and temperature at the water Condensor inlet reduced considerbly, so I thought no vapour flowing so switched the process off.
When i opened the retort i found nearly 30 kg of unburnt yellowy waxy Hydrocarbons, was expecting black Char.
Could somebody clarify why this unburnt?
Can it be due to too low a retort temperature, can the Reflux now be Too big?
Its puzzling me

HI there,

1. 380deg cel is not sufficient. Increase Temp to 400 - 420 deg.
2. what was your temp reading for the reflux?

[dippy909]

Thanks for the quick reply,
reflux went upto 300 C

[Babataku]

Thanks for the quick reply,
reflux went upto 300 C

Dippy,

I think you need to tweak your heating system so that you get more power out of it. maybe more insulation if you have heat losses, or simply you have a small burner for a large tank. then you might need to change and put in a bigger burner.

rgds

[dippy909]

Babataku,
yes I am revising my insulation and burner, will report back
Thanks

[rozier56]

Thks beyond,the 435*c you talk about is that measured at the retort?Also i am wondering about the reflux column sizing?What info is available regarding sizing of this unit with reference to the retort,i.e.diameter and heights etc.

[VAST]

Wonderful Information

Hello Everybody

First, I would like to thank Jetis for starting this thread, and then to all the prominent people who are willing to share their knowledge with us, like ImakeDiesel, Beyond BioDiesel, Excalibur and Asad and to all the others who have written about their experience with this process.

It was a long read, but very informative and valuable.

To those of us who wants to start doing this, the newbies, don`t rush, this is a dangerous process, no matter how you look at it, you are working with a bomb under the right circumstances, don`t take things for granted.

Read the forum from start to finish, I know we all want to build the best machine from the start, but all the experience that is given through here is so valuable, you will be able to dodge difficulties if you read through the thread from the beginning.

Don`t jump from one place to another, you will miss valuable information which you will have to go and lookup later in any case.

Make notes from the beginning, divide it into sections so that it is easy to refer back to it, copy the whole thread with all the information from who authored the post and the permanent link to that specific post, so that it is easy to find what you are looking for later in all this pages when you want to refer back to a discussion.

Make a big note for yourself about which plastics is save to use and put it right in front of all your information. I think this is one of the most important parts of this discussion so that you don`t blow yourself up by accident or your family and neighbors.

This whole process work by temperatures, if you don`t control your temperatures right, you can either endanger yourself and others or you will not get the results you aim for.

The reflux column is an important aspect to understand for your safety. Make sure you read up about it so that you can exclude the hazard from blockage in your system and the danger that can be caused here if your temperatures and reflux column is not correctly implemented.

In all this, safety should be your first concern, take the correct steps for the worst case scenario. Study what steps should be taken to douse flames that is started by oil or flammable gas, have a kill switch that can stop your process dead in its tracts for in an emergency.

Once more, thank you to all the people who are willing to part with their knowledge and experience.

In the next week, I will be starting to build my own system based on all I have learned here, I have already gotten most of the raw material together, just need a few electronics and flanges, then I can start. I’m sure that I will need lots of help and guidance, because although the principle of the system is easy to understand the reality is that it is tricky to get what you desire.

[Excalibur]

Hi folks, please note this is a picture of my finished plant.Note that we are using lpg gas as our heat source.The retort is a 220kg capacity plant going through a retort system into a triple tree condenser,product collected in first tank,gas then collected and pushed through attached water bubbler and returned to retort for burn-off.My question remains at what temps are you burning at and at what point are your measurements taken?I wish to maximise my system.

Up to 425*C retort however if gas flow and drip rate are good I use less. The thermocouple probe is at the top of the retort.
Perhaps you mean flame temperature? I used up to about 800*C measured just after the turk burner head.

(Feedstock mostly Hdpe/LDPE)
Reflux was increased to 4 feet with a series of baffles and catalyst (red Clay).

Fuel out put wasfeedstock was around 100kg
First Condensor: Duel was dark brow/Yellow Clear 20 liters, SG was 0.85
Second condensor (After water cooling) out put was dark brown/yellow clear 9 liters SG was 0.75. I thought this was good as petrol, put it in one of my cars and the engine was missing badly.

Could this be due to pre ignition? too low Octane? kindly help me clarify the problem.

Also the process took ages 2 hours to heat upto 250 C but peaked at 380C.(after 4 hours)
The Gas slowed down after 6 hours and temperature at the water Condensor inlet reduced considerbly, so I thought no vapour flowing so switched the process off.
When i opened the retort i found nearly 30 kg of unburnt yellowy waxy Hydrocarbons, was expecting black Char.
Could somebody clarify why this unburnt?
Can it be due to too low a retort temperature, can the Reflux now be Too big?

Your .75SG is very close to some petrol SG according to SG charts. Does it ignite with a match-stick? I tried some in a lawnmower, it took some convincing to start but ran well enough to mow lawn. Be sure to filter it.
Making effective petrol won't be a simple as diesel. There's octane to consider for one thing.

I agree with others, it sounds as though you don't have enough heating power and/or the heat losses are too big. It takes a surprising amount of heat to bring a retort up to 400*C, more heat than many would think.

Given that the diesel SG is good then one could reason that the reflux is working OK. With increased proposed retort temperature, that balance might change. Be ready to tweak the reflux temps to suit.

It may have been that when the gas flow stopped after the 6hrs, the target boiling point of the feedstock had risen above the 380*C your system peaked at. It would be prudent to notarize the feedstock quantity and balance it against production. In this way, you can be sure how much there is left in the retort.

Thks beyond,the 435*c you talk about is that measured at the retort?Also i am wondering about the reflux column sizing?What info is available regarding sizing of this unit with reference to the retort,i.e.diameter and heights etc.

Yes, 425*C is retort temperature.
Probably 20 -25% is about right for reflux to retort ratio.
I'm thinking of reducing mine slightly in size if I don't get the temperature to stay high enough for my system. (See blog for current dimensions)

Welcome VAST

[Beyond Biodiesel]

Babataku,
yes I am revising my insulation and burner, will report back
Thanks

I find 4" (10cm) of good insulation works well. The first inch (2.5cm) should be high temperature insulation; after that you can get away with simple cardboard, unless you use a flame for heating.

Thks beyond,the 435*c you talk about is that measured at the retort?Also i am wondering about the reflux column sizing?What info is available regarding sizing of this unit with reference to the retort,i.e.diameter and heights etc.

Yes, I have a thermocouple that goes down to just 1 inch (2.5cm) above the bottom of the retort. I then I have a thermocouple on the exit of the reflux.

The reflux should be about 1/4 the size of your retort.

Hello Everybody

First, I would like to thank Jetis for starting this thread, and then to all the prominent people who are willing to share their knowledge with us, like ImakeDiesel, Beyond BioDiesel, Excalibur and Asad and to all the others who have written about their experience with this process.

It was a long read, but very informative and valuable.

To those of us who wants to start doing this, the newbies, don`t rush, this is a dangerous process, no matter how you look at it, you are working with a bomb under the right circumstances, don`t take things for granted.

...

Once more, thank you to all the people who are willing to part with their knowledge and experience.

In the next week, I will be starting to build my own system based on all I have learned here, I have already gotten most of the raw material together, just need a few electronics and flanges, then I can start. I’m sure that I will need lots of help and guidance, because although the principle of the system is easy to understand the reality is that it is tricky to get what you desire.

Welcome, VAST, and thanks for posting some excellent advice here.