Biodiesel class

I was thinking of teaching a biodiesel class and now with the latest gas scare, it may make this class much more important!!
Does anyone have a biodiesel generator or motor we could use to test?

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I have five gallons on methanol and about 5 pounds of KOH. We could probably get waste oil from local restaurants, in which case best to treat oil to remove water/FFA. Would also need way to stir and heat, one popular approach (if you are making biodiesel in vehicle fueling quantoties and not just demo quanttites, is to modify a water heater.

A very small scale demo (just a liter or so) makes a good class. We have everything we need for that (heater-stirrer, pH meter, chemicals). We would just but a bottle of veg oil.

My absolute favorite guide to tall biofuel technique is ā€œjourney to foreverā€:
http://journeytoforever.org/biofuel.html

Please check it out.

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Ya I want to do it, but we donā€™t have an engine to run it on?

Not sure what you mean by ā€œwe dont have an engineā€. Do you mean a diesel engine to run on the biodiesel? Making biodiesel on a demo scale, a liter of fuel will not get an engine too far anyway. You donā€™t need an engine to verify that you have made biodiesel. The separation of the glycerol layer is very easy to see by eye, and much more convincing than demonstrating that a diesel engine can run on the top layer. A diesel engine can run on the vegetable oil you started with, too, so that would not prove you had made anything at all.

If there are people interested, there are wonderful designs for continuos flow (rather than batch) processes. The equipment for flow based processes is much smaller, only the feed and collect resoirvoirs need be large. Wonder how many makers have diesel cars or trucks?

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Is it wise to make fuel that we canā€™t burn? What will we do with it?

For just $500.00 you could a acquire a maybe-working lab engineā€¦

still dont get the purpose of the engine. If it is not meant to show that you have really made diesel, what is it for? Why run a lab engine inside, make some pollution, just to see it spin? Now if we had something we wanted to hook that engine up to, thats different.

If it is a question of disposing of demo fuel, I am sure that someone in the makers has a diesel car. Could just pour product into tank. I will send shout see who answers.

Soā€¦
you SAY you donā€™t get the purpose of the engine, but then expound on the reason for which itā€™s desirable, so it seems like you DO get it.
Saying you made biodiesel is one thing to an observer.
Them observing said biodiesel perform the function of diesel is another. And doing so in a relatable way, another still.
At a bare minimum, running an engine that does nothing is a demonstration thereof. Making that engine power something would be a logical expansion.
Making that something a vehicle is (for most observers) the ultimate demonstration.
So, yeah. Make biodiesel. Nifty.
Use it to make an engine spin. Cool.
Make the engine power something (generator, so you can measure the power output, for example, or a propeller, so you can feel the air it can move): COOL!
Make it power something they can drive (e.g. a go-kart to putt around the back lot in): BITCHINā€™!
Itā€™s just a way to bring the theoretical production of biodiesel from VO into the ultimate reality. EXACTLY how thatā€™s accomplished is pretty darned open-ended, with one path being an internal combustion engine. The upside of that is: virtually every observer in the developed world can relate.
Unfortunately, most observers will be underwhelmed if you point to a bottle of biodiesel and SAY you made that, and it can do stuff. Showing them will work much better.

I think @TLAR has experience with biod, but I donā€™t know if he has any vehicles currently available for ā€œdisposingā€ thereof. I would volunteer the 'SpaceShuttle, but thatā€™s not within the scope of my authority. Iā€™d be interested to see if you get any takers if you put the word outā€¦ If you can get someone to do what this person does in this video, itā€™ll have impact.
(less than a biodiesel powered run in a go-kart, butā€¦)

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You do realize that the same engine would also run on plain vegetable oil. So we could start with plain vegetable oil, do absolutely nothing to it, then claim we converted it to biodiesel, with the ā€œproofā€ being that the go-kart will run on it.

to show by a practical demonstration that what you have is no longer veg oil, running a cart is not it. The main advantage /difference of biodiesel over plain veg oil is that it has less tendency to gel at low temp and stores better.
There really is not an interesting ā€œrelatableā€ demonstration of these properties.
Yet easy to show chemically that you have indeed transformed the veg oil into something else. If you say that the class members have no interest in chemistry, well thay are in the wrong class, they are looking for a class on the practical aspects of making fuel on a consumer scale. Dont get me wrong, that would be a great class, but much more challenging to put together and would definitely need a consumer for the fuel. And even those people would be better off truly understanding the chemistry. I thought demo (1 L) scale would be a good start.

Sorry. I misunderstood. I got the impression that we were looking to make people interested in the science of biodiesel production via practical demonstration.
Yes, I realize you can run SVO.
Thereā€™s a chemistry class (or 2) to have behind doing that well, too, as well as the possibilities for various physics classes.
But if you want to hook the interests of looky-loos on the science (i.e. draw a larger audience), itā€™s beneficial to demonstrate relatable practicality.

If you do not want to make people interested in whatā€™s going on, keep the scope of relatability and appeal narrow. Either way, suits me fine. Josh appeared interested in a practical demonstration of using the end product.

You are correct.
Godspeed.

Saw the video. Note that this took four days, mostly time to settle out glycerol from gallons of fluid.
The product she made is ghastly, caustic and sure to destroy her car in time. T No question she made some biodiesel, or there would be no glycerol, but here was no washing step, no heating, really feeble mixing, this would have had very low yield. She could just as easily said some magic words, put the waste veg oil into her tank exactly as it was, without any methoxide, and her car would have started just as well.

The liter-scale demo can be done within a class period and makes a really pretty product, because it is so much easier to thoroughly and evenly heat, mix, wash, and settle a small volume. I will look for a good video, but in meantime what you get is a golden liquid that you might actually be willing to put in your tank, floating above a clear gooey well-defined layer that is glycerine and looks like it, rather than like toxic sludge.

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:+1:

I played with biodiesel for a while over ten years ago. Now itā€™s hard to scavenge WVO from restaurants. They have people who pay to pick it up or take it for free as a service. If you raid their barrels, they get kind of upset about that. I had a couple sources but they now have contracts with companies to pick up.

OTOH, you might find some small restaurant with WVO or you can frequently find WVO cheap on craigslist either as people reselling it or people who started to do biodiesel and got tired of it and have it sitting around.

If you use WVO directly, it must be highly filtered or (better) centrifuged to first clean it.

Itā€™s not entirely true that you can sub WVO for biodiesel. WVO is triacylglyceride and biodiesel is typically the methyl ester of the fatty acid from the TAG. Depends on the car, the engine, the temperature whether you dilute it or not with regular diesel. Hot weather with a warm engine might run warm WVO just fine but you must flush the system with some version of ā€˜dieselā€™ before shutting down in many cases to prevent a gooped up system when things cool down. This means you need a fuel heater system and a fuel mutiplexer.

Since many folks wonā€™t be running on pure BD, a good compromise is to skip the biodiesel steps and just add the filtered WVO to the diesel tank. Different vehicles have different tolerance to this.

One of my farm neighbors told me that his truck fleet routinely filtered their waste crankcase oil and just added it to their diesel for 40 years without incident. Indeed, Iā€™ve seen systems for centrifugation of waste engine oil to reuse in the tank with diesel or to use as a heating oil.

Iā€™d love to learn about the continuous flow process or in any case keep up with this project!

If you can find it, a Lister diesel (generator) is a great engine to use to test your product. It will run on just about anything.

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There are many folks that run old ATF in their diesels as well.

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I have two other diesels than my commuter carā€¦the older vane type injection pump diesels are often better suited for waste veggie oil.
My non injection pump diesel ( commuter car) does fine on B10,B20 and todayā€™s low sulphur diesel but I wouldnā€™t put home brew in it without close scrutiny.

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Arenā€™t all of our fuels bio? Petroleum products are most definitely derived from biological sources.

And what about wood gas as a fuel source?

https://makezine.com/2010/06/24/lost-knowledge-wood-gas-vehicles/

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Wonderful to hear from someone with actual biodiesel experience!

I did not mean to suggest that running wvo was a good idea, just that the stuff that the lady in jasts video was putting in her unfortunate vehicle as biodiesel was, if anything, worse than the wvo it started as. Also meant to say that merely starting an engine is not proof that you made good clean biodiesel at high yield. It is not a suitable test of product quality. A better test would be running the engine for years then looking at its gaskets; that would tell how much you had actually improved the wvo.

It may be that I am missing the point; if the idea is to show that you can recycle something that is essentially garbage, obtainable cheap and often free, and burn it in an engine, even if only once, then of course it would not do to use clean veg oil as a start because that makes no economic sense, it costs more than the diesel.

The idea of the continuous flow is that the actual kinetics of transesterification are really fast, the reason making biodiesel takes hours and hours is in the really poor contact between methoxide and oil when you mix them with a paddle and electric drill, as people do. If the reaction mix is emulsified, the reaction takes place much faster for same reason finely divided chemicals generally react faster. (term for this is micromixing). There are other reasons for higher efficiency, surprised that continuous never caught on. Some of the reactors are too fancy for us, but some are quite makerspace-makable, I think more so than having hundred-gallon process equipment. We could profitably make dieel from wvo, but on that scale I think it would be extremely advisable to use at least a two-stage process and not just filter the wvo to remove BCBs (burnt crunchy bits) but also chemically clean up things like free fatty acids.

Anyway, large scale diesel would need someone really committed to making all his own fuel. If there ever is such a person, I know a restaurant owner who has offered me his wvo for biodiesel. This page are some good processors, including one of the simplest continuous systems:
http://journeytoforever.org/biodiesel_processor.html#continuous

I would prefer to explain the chemistry without giving the impression that making fuel from trash oil is quite as easy as it is sometimes made to appear. Then someone wrecks their gaskets with bad biodiesel and it gives all of BD a bad rep.

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Stop being pedantic, Walter!
Weā€™re talking making biodiesel in a 2 hour classroom setting. Not cloning dinosaurs a-la Jurrasic Park, waiting around for ANOTHER chance meteor strike, and then waiting some MORE for them to get squished into fuel! We donā€™t HAVE that kind of time!

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But just think what a wonderful end that would be for all the lawyers!

P.S. Will not all of our cemetaries turn into petroleum eventually. Instead of soylent-green,perhaps we could have soylent-gas for our cars.

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They will not, as those bodies decay before their juices can be pressed into oil.
Thatā€™s why you need to add the secret ingredient: chance meteor strike, SUDDENLY burying everything in tons of dust.
Er, at least, thatā€™s how I understand the science behind dino-oilā€¦