How to turn plastic waste into diesel fuel cheaply

[Excalibur]

Can anyone translate this to English

Mr.Google translates it as:
Hello Alexander. Took time with this topic but I slowly and trying to learn from everyone and everything, now bought a grinding mill 10 HP and am making plastic collection in good condition and have two tons of shredded plastic packaging. Pending start another process more refined as yours. u7n greeting. I might add photos

Photos would be great. Thanks.

[wheels]

Mr.Google translates it as:
Hello Alexander. Took time with this topic but I slowly and trying to learn from everyone and everything, now bought a grinding mill 10 HP and am making plastic collection in good condition and have two tons of shredded plastic packaging. Pending start another process more refined as yours. u7n greeting. I might add photos

Photos would be great. Thanks.

10Hp mill. That's a sizable investment.
2 Ton of Plastic. I hope he has done his homework. There is not much call for 2 ton of wax struck inside a steel vessel. As one or two have found out already.

[alejandroramallo]

With the time I will upload photos. Regards

[rozier56]

rozier56

Latest System!
This system has a 260lt retort with a 90lt re flux
We are using pp and pe as plastic raws.
Retort temps are 480- 510*c.
Reflux temp is 280-300*c.
Condenser is counter currently cooled.
Diesel collection chamber kept at 65-70*c.
Diesel collected varies between 0.79-0.82 on hydrometer.

Tried to increase reflux to 320*c and up to 350*c and started producing some wax content.Was trying to increase capacity but ran into wax situation.This also can cause blockages to inline filters and burner nozzles when wax particles are present in the burner fuel supply.

I have found that my production flow is reduced when the burner temps required at the reflux is reached and the burner switches off.The temp will increase by approx 10*c and then drop down approx 10*c below the set reflux temp{280*c} before the burner re-ignites.This is the time when production slows a lot.
Sounds like i need better burner control,or the ability to control the burner flame?What ideas are there out there?
Would also like to know were i can get info on the chain lengths for different plastics utilized ie; ldpe and hdpe,pp,pe,etc

[wheels]

Latest System!
This system has a 260lt retort with a 90lt re flux
We are using pp and pe as plastic raws.
Retort temps are 480- 510*c.
Reflux temp is 280-300*c.
Condenser is counter currently cooled.
Diesel collection chamber kept at 65-70*c.
Diesel collected varies between 0.79-0.82 on hydrometer.

Tried to increase reflux to 320*c and up to 350*c and started producing some wax content.Was trying to increase capacity but ran into wax situation.This also can cause blockages to inline filters and burner nozzles when wax particles are present in the burner fuel supply.

I have found that my production flow is reduced when the burner temps required at the reflux is reached and the burner switches off.The temp will increase by approx 10*c and then drop down approx 10*c below the set reflux temp{280*c} before the burner re-ignites.This is the time when production slows a lot.
Sounds like i need better burner control,or the ability to control the burner flame?What ideas are there out there?
Would also like to know were i can get info on the chain lengths for different plastics utilized ie; ldpe and hdpe,pp,pe,etc

Many questions.
But firstly, the main answer is, you lack control.
Is the Retort fixed, or are you rotating or stirring the contents in some way? When you have a large Retort Vessel, the issues you run into is producing enough heat and getting that heat all the way through the Feedstock. There is a great importance in heating all the plastic as evenly as possible and maintaining an even heat distribution through the entire contents. Plastic is a very good heat insulator. If you use a Vacuum in the retort, the heat insulation is even greater. Using an inert gas does in some respects work to help heat getting through the contents better. But once the Plastic has melted and become one mass, then the insulator is back anyway. Why is this important? Well this answers your last question. The molecular weight of chains varies. Although PE initially produces a longer chain length than other plastics, once the plastic has been vaporized, the chains are in a continual state of change. They are breaking, but some join as well. The hotter you get the stock before the Vapor leaves the Retort, the more active the Chains and the more they break apart. So higher temperatures produce shorter chains. PE is also the culprit of producing Wax. But you can reduce or even eliminating that production with greater heat control. Either pyrolyzing the Stock above or below the Wax producing Temperatures. But the issue with being able to do this is getting the Target temperature all the way through the plastic as evenly as possible. If you can imagine, the internal temperature is going to be higher on the outer contact area of the Stock and it will be lower on the inside. Depending on the Plastic type, Vapor is released from ~350degC and on up. So lets say the Heat is 350deg at the centre area of the plastic mass, it may be 500degC on the outside. So you will get a different chain length being released throughout the plastic stock. This is one of the many reasons why commercial plants have so many varied plant designs with their Retorts. There is no one answer to all problems. Each design has a benefit and any negatives.
Reflux! It's way to big. Reflux is just about returning the really heavy chains back to the main source of heat, being the Retort, so they can be heated further and hopefully Broken. You don't need any large vessel to do this and it only makes it harder to heat. The lower temperature range of the Reflux needs to be the lowest temperature of the Chain length you require. So chains longer (thus heavier) than Diesel Fuel weights, will be returned to the Retort to be broken further.
Diesel weight chains start at about 150deg and range up to 260degC. So your main Distillation vessel is far too cold.
For the burner. I suggest you use Fuel that is not being immediately made. Make sure you use Fuel from a previous run and then filter it before burning it. But if you really have to use the fuel as it is produced, then the best way to stop it waxing in the line is to heat the line slightly. It does not need a lot of heat. Maybe even just insulation would suffice. Wax formation happens when the Fuel drops below 60degC or even lower.

Finally, and this is aimed at everyone in general. Stepping up the size of a Plant results in the issues and costs to rise exponentially. It is why fully understanding what happens internally, where, when and why is so important. It is why no large scale plant uses the same designs that back-yarders do. It is not just a case of heating plastic and then having it condense out onto a usable liquid. This is Chemical engineering. It requires a lot of knowledge, understanding and technical ability and all those abilities need to rise four fold with every step up in size. the Key is, keep the plants small and controllable. Once you step up to a plant than is going to produce more than a Vehicle tankful of fuel at a time(and maybe not even that), then you are entering a whole new realm in complexity. .
I hope that helps

[piccolo chimico]

Very good explanation Whell

[alejandroramallo]

Wheels, I take my hat off to you. The explanation was impeccable.

[wheels]

Wheels, I take my hat off to you. The explanation was impeccable.

Thank-you. It's nice to know I am communicating complicated info across OK.

[Excalibur]

Latest System!
This system has a 260lt retort with a 90lt re flux
We are using pp and pe as plastic raws.
Retort temps are 480- 510*c.
Reflux temp is 280-300*c.
Condenser is counter currently cooled.
Diesel collection chamber kept at 65-70*c.
Diesel collected varies between 0.79-0.82 on hydrometer.

Tried to increase reflux to 320*c and up to 350*c and started producing some wax content.Was trying to increase capacity but ran into wax situation.This also can cause blockages to inline filters and burner nozzles when wax particles are present in the burner fuel supply.

I have found that my production flow is reduced when the burner temps required at the reflux is reached and the burner switches off.The temp will increase by approx 10*c and then drop down approx 10*c below the set reflux temp{280*c} before the burner re-ignites.This is the time when production slows a lot.
Sounds like i need better burner control,or the ability to control the burner flame?What ideas are there out there?
Would also like to know were i can get info on the chain lengths for different plastics utilized ie; ldpe and hdpe,pp,pe,etc

It's great that you are trying new setups because you can learn what works best by comparison.
The hydrometer readings are overall a bit light. I suggest you raise the reflux temperature but do not increase the retort temperature to do so. There are several options to engineer this, some may or may not apply.
1/. Reduce reflux volume
2/. Insulate reflux.
3/. Move reflux closer to retort.
If your retort temperatures are not producing wax or suffering boil-over then it's difficult to argue the temperature level is not OK.
The diesel collection chamber temperature is satisfactory for those who want to maximize the amount of liters made with any reasonable stability. The diesel made like this though not absolutely perfect by industry standard will work well enough for DIY

Burners that have only one setting aren't ideal. Better would be some way of tailoring the flame heat to suit the retort requirement on the fly. One thought is to adapt a fuel pressure control adjustment. Another idea is to use multiple fuel nozzles, each with an individual valve or solenoid. Either of these ideas may require air adjustment compensation for ideal air/fuel ratio.
Currently Orion runs a injector pump with 4 fuel nozzles. There are 2 settings, power mode and idle mode, each has manual min/max adjustment screws. A solenoid responding to retort temperature switches between the 2 modes. My thought at a later more advanced stage is to re-introduce Arduino to control a servo on the fuel throttle based on retort temperature.

[MangiPNG]

Hi Guys,
Good to be back.. I see a lot has gone on since I've been away. Still reading through with great interest. Well I've stopped construction on my larger plant and decided to build a small lab scale one first so I can easily tweek and test different catalysts. Plus the explosion will be kept at a minimum. I've posted a pic of my work (still under construction) and encourage all your comments please.. Good and Bad!

[wheels]

Hi Guys,
Good to be back.. I see a lot has gone on since I've been away. Still reading through with great interest. Well I've stopped construction on my larger plant and decided to build a small lab scale one first so I can easily tweek and test different catalysts. Plus the explosion will be kept at a minimum. I've posted a pic of my work (still under construction) and encourage all your comments please.. Good and Bad!

Excellent choice on starting small. I suggest you start with no catalyst and then use that as your reference point for your experiments. It is also worth doing tests with each plastic type separately and then with a mix of all types. Take note of your results.
It is also as important to learn about the Catalyst. It is important that the Catalyst is heated. A reaction requires energy. For many Chemical reactions, the energy(heat) is produced by the reaction. For a Catalyst, the heat needs to be input to cause the reaction to start. For some Catalysts, once the reaction starts, Heat energy is then continually produced as the reaction continues. Metal based Catalysts are common with that aspect. If you can place a temp sensor in the catalyst and watch the temperature slowly increase and then suddenly increase, that is usually a clue as to the activation temperature. You can often measure a lower input Gas temperature and a higher output gas temperature.
And most importantly, have fun

[Excalibur]

Excellent choice on starting small.

It's much easier to modify, tune and tweak a small installation. By comparison big rigs are exponentially much more difficult, costly and time consuming. The thought is to do all the learning, testing and trials on the small, easy to work on plant then once it's up to speed, look at how it can be up-scaled.

[tesssweet]

I would love to come out and interview you for a film I am writing. This device looks amazing!

[Excalibur]

Orion made about 240 liters of diesel after major reconstruction work. There were a few problems with leaks, insulation, pumps etc. Feedstock was a variety of recycled waste oils, gear oils, hydraulic oils, engine oils etc. Actual production time was about 8 hours. Diesel measures at .848SG. Color ranged between light amber ~ ruby red ~ dark green depending on the thickness of transparent vessel the fuel was contained in. The fuel looks like the oil it was made from except specific gravity is close to target. Actually I was aiming for a slightly lighter weight but with all the running around, I elected to largely ignore the reflux temperature.

A new method of weighing the retort was trialed with success. A revised preheater is working well with further improvements likely. The I.D (induced draft) fan was particularly pleasing with considerably less lazy smoke wafting around. The retort insulation was a disappointment requiring more heat to overcome the inefficiency. The brickwork appears to be working nicely however these are not insulators so they store and conduct heat.

One really interesting phenomena discovered toward the final stages was the performance with low feedstock level in the retort. It was producing at a good clip with significantly less required heat. It will form the basis of the next run to see if any good, improved efficiency can be found.

More detail will be on DIYDiesel blog in coming days. As has been the custom, many of the early, obsolete postings will be retired to the redundant archive page.

[Babataku]

WMO Blend or WMO pyrolysis

Quick question for those who have done some WMO&RUG blends 80%WMO and 20%Gasoline...

My question is which is better quality diesel fuel? The one produced from pyrolysis process of WMO or simply blending WMO with gasoline? Or its just the same?

I have access to free WMO and want to know if there is any benefit for me to process in my small plastic pyro plant or I can just blend and pour in my tank...this will be simpler for me.

I know Excalibur has done WMO blends in the past and currently doing WMO pyrolysis as well as beyond biodiesel...

All comments are well come.