Question about biodeisel fuel (Alternative Energy)

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I was reading the article on biodeisel fuel in the Jan/Feb 2001 Countryside. While finding it interesting, I noticed that the process relies on used vegetable oil. What I am curious about is if anyone has been able to derive the vegetable oils from matter raised on their homestead to make the fuel from instead of depending on restaurant wastes. My thought is that if the methyl esters could be processed directly from homestead raised matter, this could be a truly self sufficient fuel source.

-- Jay Blair in N. AL (jayblair678@yahoo.com), March 25, 2001

Answers

Corn oil is made a lot like olive oil that has been home processed for centuries. The corn germ is dried in a kiln, and the oil is extracted by either a hydraulic or a screw press; the pressed cake is further treated by washing it with a solvent, ordinarily hexane, and the dissolved oil is recovered by evaporating the solvent.

Course then you have the problem of how to produce the solvent hexane on the homestead. This can sorta escalate and pretty soon you have an industrilized society instead of an agrarian one.

-- Lynn Goltz (lynngoltz@aol.com), March 26, 2001.


I read that article with great interest also, Jay, it doesn't quite seem practical for home small farm production. A better idea seems to be home/farm ethanol production from potatoes or corn, something all of us can raise cheaply and readily. During WWII, most all German farmers participated in making ethanol on the their farms, even the small holdings participated in this process, which is a simple still set-up to produce pure ethanol. Most all gasoline engines can be converted to burn pure ethanol easily, and it's better for the engine and the environment as less pollutants are produced. Ask any German farmer that is old enough to remember war time provisioning, and they will tell you all about home produced ethanol, this, in my opinion, is closer to true self-sufficiency.

-- Annie Miller in SE OH (annie@1st.net), March 26, 2001.

Both biodiesel and ethanol can be homestead grown, and are, in third- world countries. In fact, Rudolf Diesel developed the engine for straight vegetable oil around the end of the 19th Century. A number of people are following his example or are mixing veggie oil (new or used) with kerosene or petro-diesel fuel. Mixtures are commercially available in Minneapolis and are being used in Cincinnatti busses.

There are drawbacks. Ethanol needs a fuel for distillation and has legal complications (not insurmountable) and biodiesel is biodegradeable, so it must be preserved in some manner for storage. Also, both fuels involve risks; they burn, obviously; and there are toxic chemicals involved, particularly with biodiesel. But several people have build reactors using things like vacuum and bilge pumps plus old water heaters, etc. that pretty much isolate you from the nasties.

All-in-all, it is very feasible. Ethanol requires mods to carbs or fuel injection and biodiesel or veggie oil can be used with little or no modification to the engine. Potentially, except for road tax and sweat equity, it is all very low-cost fuel.

But please understand, I am not writing from hands-on experience (I'm still stuck in the city) but rather reading from the immense and growing literature on the web, in magazines and an increasing number of books. I find this tremendously intresting and hope to use this grass-roots technology in the near future.

Here are a few links to get you started:

http://journeytoforever.org/biofuel_library.html

http://www.biodiesel.org/

http://www.veggievan.org/

There are many, many more.

-- Marty Boraas (boraas@miliserv.net), March 26, 2001.


Thanks for the info and directions to look into. My son and I will use this for our summer study project after our worm study is completed.

-- Jay Blair in N. AL (jayblair678@yahoo.com), March 26, 2001.

I've been making bio-diesel for about three years now here in England. The cost of petrolium diesel is prohibitively expensive (about the equivalent of $7.00 a gallon). I've tried using veg oil / methanol / sodium hydroxide and veg oil / ethanol / sodium hydroxide, I've even tried making potassium hydroxide as a catalyst from wood ash. Anyway, the best recipe I found for independant production is the veg oil / ethanol / sodium hydroxide combination. I extract the oil from rape seed, and sunflower seed by passing the seed through a meat grinder to break it up, heating the seed to loosen up the oil and then I press it out using a home made contraption as follows: Four pieces of railway tie timber. Two upright and two horizontal. Each piece is three feet long. The uprights have mortices cut into them and the horizontals have tennons cut to fit into the mortices. The frame makes a square shape into which tremendous pressure can be applied. I then place a piece of six inch diameter steel pipe on top of the bottm horizontal frame. The pipe is drilled all around the bottom with little holes to let the oil out. A round metal plate is then placed in the bottom of the steel pipe section and some crushed, warm seed is put in. A second steel plate is then placed on top of the seed and more seed is put in. This is repeated until the pipe is full of seed and metal plates (you'll see why in a minute). I then place a 10 ton bottle jack on top of the top steel plate and under the top horizontal part of the frame. I crank the jack applying a pressure on the seed. When I have cranked enough, oil is squeezed out of the cracked seed and oozes out the holes in the bottom of the pipe. The oil drains into a container. When the oil stops flowing, I crank again until more oil flows, then I leave it until it stops and repeat the process again until I can get no more oil out of the seed.

At this point I have seed cake in the pipe and I release the jack, take the pipe off the frame, push the seedcake and metal plates out of the pipe and break the plates away from the compressed seedcake. By using a number of plates, the seedcake breaks up into smaller useable pieces which I supply to a local farmer as animal feed. (In return , he gives me the raw seed to work with). He prefers the seedcake I provide as I can only get between 40 and 50% oil extraction using this method (the commercial boys get 90% out leaving less nutrition for the beasts). The method of oil extraction is exactly the same as using a screw press, except I don't have a screw mechanism and the whole rig is home made from junk.

Once I have the oil, I make ethanol using a pressure canner with the weights removed, and a copper coil attached to where the weight usually sits on top. I put a thermometer in the little grommet hole where the safety valve goes and the copper pipe spirals down into a large stock pot (with a tap on the base). The tap is attached to the other end of the copper pipe and the stock pot is filled with cold water and topped with ice cubes when necessary. For the mash, I put warm water and sugar in a large plastic bin, add the yeast, wait for it to froth and then settle, top up with water, lid it and let it work for a couple of weeks. Then I tripple distill the mash and cook up some really neat shine...I mean ethanol.

I can then strip the still down to a pressure canner stockpot and some bathroom pipe and nobody is any the wiser.

The only thing I buy is the lye. I have yet to find a way of home- making such a strong alkaline. The sodium hydroxide (lye) is added to the ethanol making sodium ethoxide and this in turn is added to the veg oil. It's all done in a big old oil drum. The mix is stirred for an hour or so using a black and decker power drill and a paint stirrer. It's let to settle overnight and in the morning I have a drum with bio diesel floating on top of some nice glycerine. I drain the glycerine off for later use making soap, and put the bio diesel through a five micron fuel filter and it's ready to go straight in the fuel tank of my VW camper van. I have a spreadsheet that works out exactly what you need using any of the recipe combinations if you put in the amount of oil (it tells you the rest of the ingredients). One advantage of using new oil is the recipe is fixed as the acidity level is known. Using old oil requires testing to adjust the amount of lye to compensate for the increase in acidity in old oil (the more frying done with it, the more acidic it gets). If anybody wants the spreadsheet (Excel 98) email me and I'll forward it as an attachment.

Hope this post isn't too long and is of some small use.

Eric

-- Eric J Methven (e_methven@btinternet.com), March 26, 2001.



The book written by the VeggieVan people mentions a much more abundant source of oil that can be used for bio-diesel production: algae.

They mentioned that if all CRP land was growing rapeseed, the resulting canola oil would be able to produce biodiesel, which could then fill only about 20% of the petroleum diesel market. Therefore, we would not be able to grow enough crops on currently-vacant land to reduce our foreign oil imports significantly.

However, a square foot of algae growing space produces much more oil than a square foot of rapeseed field. Furthermore, they love hot, sunny conditions for the pools that they grow in -- therefore, arid and desert regions are perfect for algae farms (don't need to sacrifice production of traditional crops to replace diesel market).

Even if that does not happen, imagine if our farms (growing rapeseed) were used to use reduce our dependence on imported fuel. Instead of growing crops that are dumped at cheap prices and then turning around to buy oil at high prices -- what a joke. The best would be able to keep growing food for the world while using the arid/desert regions to grow algae.

-- Michael Olson (olsonmr@yahoo.com), March 29, 2001.


Thank you all for the wide range of perspectives. I am sure many sleepless nights lay ahead for me while I study on these. Thanks.

-- Jay Blair in N. AL (jayblair678@yahoo.com), March 29, 2001.

Erik, I would be very interested in your processing method using ethanol rather than methanol for your catalyst.Do you have any figures as to percentage of ethanol? Is the process the same as using methanol?I have wanted to make a few batches of biodeisel but the only info I found used methanol and said that ethanol involved a different process.Of course methanol racing fuel disappeared from local supply about the same time that the folks in the "Veggie van" made it into the news.I'm sure there is no connection.

-- greg (gsmith@tricountyi.net), March 30, 2001.

My question is this - if Mr. Diesel made his engine to run on straight veggie oil, can you still run old diesels on the pure stuff? My understanding is that you have to estherize it to thin it out so that it can pass through the feul injection system. If this is so (and it very well might not be), then couldn't you run straight oil in a non-injected feul system? If not, then how could you go about modifying an engine to run on straight oil? Seems like the cost of mods would balance out by eliminating the cost of preparing veggie-diesel the way its's done now.

-- Soni (thomkilroy@hotmail.com), March 31, 2001.

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