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Homemade Biodiesel This booklet is free and can be freely distributed

Darren Wood Friday, 5 May 2006

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Table of Contents

Introduction 1

Golden Rules 2

Get stuck in “The old Blender Method” 3

Biodiesel Facts 5

Three Choices 8

Using Biodiesel 13

How to build your first Biodiesel reactor 15

Making Biodiesel 29

Finally 39

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Introduction This is a quick description of the purpose of this booklet and why I’ve prepared it.

The purpose of booklet is to outline some of the procedures and equipment needed for home biofuel production and usage. It is a compilation of information readily available from the web in a compressed form. You’re basically getting all the juicy bits it’s taken me a while to find on the web. All content is published with open source or by the author’s direct consent. If you do chose to pass this information on please make sure you maintain any author’s references.

Mr. Rudolf Diesel at the 1898 Paris Exhibition showed a compression ignition engine designed by him that ran on peanut oil, his vision was one of regular people producing their own fuel from biomass (like vege oil) as a source of power for transportation, thus removing their reliance on large companies for fuel. (Ah, if only!!)

In a later 1912 speech, Rudolf Diesel said, "the use of vegetable oils for engine fuels may seem insignificant today, but such oils may become, in the course of time, as important as petroleum and the coal­tar products of the present time."

Seem a little prophetic? With the cost of pump diesel at around $1.23 this seems like an attractive option.

Today in New Zealand this could be a workable reality. Co­operatives are the way to go and mostly rural NZ could really benefit from this.

The information contained in this booklet is compiled from a variety of sources all of it is free information and there are no secrets in biodiesel production as the basic transesterification process has been known for years.

The following processes are straight forward and relatively easy, but there are 3 things to remember when doing any of the small processes below;

Safety Safety Safety

OK copy in this booklet is either copied from free websites or my own so no copyrights here!!!

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Golden Rules (never to be broken)

Always wear your safety equipment Never have Children or Pets nearby Always have proper ventilation for your

experiments Never Breath the fumes

Always have a tap with running water nearby or a hose pipe

If you spill anything stop what you are doing and turneverythingoff and clean it up

Wash anychemicals that come into contact with your skin immediately

Always apply common sense when using these highly corrosive chemicals, take care of you and

yours. If you are worried and think anything is unsafe

then don’t do it.

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Old Blender Method Sounds silly I know but this is probably the best demonstration of how the process works, you will need the following

1. 1.5 litre used glass blender with lid (cannot be used for food afterwards EVER!)

2. 1 pair of full length safety gloves

3. 1 Pair of safety goggles

4. 1 litre of fresh cooking oil (Canola is my favorite)

5. 200ml of pure Methanol

6. 3.5grams of Caustic soda (Sodium hydroxide RD1 sell it but keep it sealed until you need it)

7. Thermometer (again not to be used for anything else again)

Right then All set? Got everything ? Good then lets get cracking (do this in your garage or workshop as you don’t want the kids or Pets anywhere near these chemicals)

Put on your gloves and safety goggles.

Warm the oil to 50 degrees Celsius (Check with thermometer this won’t take long so watch it)

Whilst warming the oil put the Methanol in the blender and add the Caustic soda (only 3.5 GRAMS) do this quickly as caustic soda tends to absorb moisture very quickly and mix on a low speed for 2 minutes or so. This reaction produces heat so make sure the blender is a glass one.

Add the oil to the blender with the methanol caustic soda mix in it.

Blend on a medium speed (Remember we don’t want any spillage) for about 15mins or so.

You can then leave the solution to settle in the blender (It shouldn’t take more than an hour)

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You should end up with to different colored liquids a light on top the other darker and at

the bottom. If you didwell done! you just made biodiesel!!! (the top lighter bit)

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Biodiesel Facts The following is taken form the Journey to forever site and I have left the links to that site intact in the word (.doc) form of this document

“Biodiesel is much cleaner than fossil­fuel diesel ("dinodiesel"). It can be used in any diesel engine with no need for modifications ­­ in fact diesel engines run better and last longer with biodiesel. And it can easily be made from a common waste product ­ ­ used cooking oil.

• Biodiesel fuel burns up to 75% cleaner than conventional diesel fuel made from fossil fuels

• Biodiesel substantially reduces unburned hydrocarbons, carbon monoxide and particulate matter in exhaust fumes

• Sulphur dioxide emissions are eliminated (biodiesel contains no sulphur) • Biodiesel is plant­based and adds no CO2 to the atmosphere • The ozone­forming potential of biodiesel emissions is nearly 50% less than

conventional diesel fuel • Nitrous oxide (NOx) emissions may increase or decrease but can be reduced

to well below conventional diesel fuel levels by adjusting engine timing • Biodiesel exhaust is not offensive and doesn't cause eye irritation (it smells

like French fries!) (Or donuts or sausages depends on the source really had KFC once!)

• Biodiesel is environmentally friendly: it is renewable, "more biodegradable than sugar and less toxic than table salt" (US National Biodiesel Board)

• Biodiesel can be used in any diesel engine • Fuel economy is the same as conventional diesel fuel • Biodiesel is a much better lubricant than conventional diesel fuel and extends

engine life ­­ a German truck won an entry in the Guinness Book of Records by travelling more than 1.25 million km (780,000 miles) on biodiesel with its original engine (this is an important bit to remember)

• Biodiesel has a high cetane rating, which improves engine performance: 20% biodiesel added to conventional diesel fuel improves the cetane rating 3 points, making it a Premium fuel

• Biodiesel can be mixed with ordinary diesel fuel in any proportion ­­ even a small amount of biodiesel means cleaner emissions and better engine lubrication: 1% biodiesel will increase lubricity by 65% (Another important one)

• Biodiesel can be produced from any fat or vegetable oil, including waste cooking oil.

See the National Biodiesel Board's complete evaluation of biodiesel emissions and potential health effects, in accordance with the most stringent emissions testing protocols ever required by the US EPA (Acrobat file, 40 kb):

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http://www.biodiesel.org/pdf_files/emissions.PDF

Summary:

• The overall ozone (smog) forming potential of biodiesel is almost 50% less than diesel fuel.

• Sulfur emissions are eliminated. • Substantial reductions of unburned hydrocarbons (­93%), carbon monoxide (­

50%), and particulate matter (­30%). • Biodiesel NOx emissions can be efficiently eliminated as a concern. • Substantial reductions of cancer­causing PAH (­80%) and nitrited PAH

compounds (­90%).

Diesel emissions and cancer According to a U.S. Department of Energy study completed at the University of California at Davis, the use of pure biodiesel instead of petroleum­based diesel fuel could offer a 93.6% reduction in cancer risks from exhaust emissions exposure.

The study, "Chemical and Bioassay Analyses of Diesel and Biodiesel Particulate Matter", 1996, used a 1995 Dodge 3/4 ton pickup truck with a 5.9­litre Cummins B Turbo diesel and tested 100% ethyl ester of rapeseed oil (REE), 100% diesel 2­D low­sulfur fuel and blends of 20% REE and 50% REE with the 2­D diesel fuel. An EPA test cycle was followed throughout. In test after test the study found the highest risk came from 100% diesel fuel, followed by the 20% REE blend, the 50% REE blend and, lowest risk, the pure biodiesel.

"Use of the 100% REE fuel produced the lowest genotoxic (DNA­damaging) activity in the tests. Blended fuels in the non­catalyst­equipped engine produced less emissions than emissions than the 100% diesel fuel... The use of the 100% REE fuel resulted in the lowest emissions compared to the REE blends and 100% diesel fuels.

"The highest relative specific mass mutagenic activity collected during either the hot or cold test cycles was the particulate matter collected from the 100% diesel fuel emissions... The lowest relative specific mass mutagenic activity was from the particulate matter collected from emissions of l00% REE fuel."

NOTE: There's nothing special about ethyl ester of rapeseed oil biodiesel, other types of biodiesel have similar results.

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Chemical and Bioassay Analyses of Diesel and Biodiesel Particulate Matter: Pilot Study ­­ Final Report by Norman Y. Kado, Robert A. Okamoto and Paul A. Kuzmicky, Department of Environmental Toxicology, University of California, Davis, California, November 1996. Acrobat file, 3.1Mb. UC Davis biodiesel study ­­ summary: the Summary, Results and Discussion sections of the report, in html format.

Greenhouse effect Using vegetable oils or animal fats as fuel for motor vehicles is in effect running them on solar energy. All biofuels, including ethanol, are derived from the conversion of sunlight to energy (carbohydrates) that takes place in the green leaves of plants.

Plants take up carbon dioxide (CO2) from the atmosphere; burning plant (or animal) products in an engine releases the CO2 uptake back into the atmosphere, to be taken up again by other plants. The CO2 is recycled, atmospheric CO2 levels remain constant. Thus biofuels do not increase the Greenhouse Effect ­­ unlike fossil fuels, which release large amounts of new (or rather very old) CO2 which has been locked away from the atmosphere for aeons.

In fact biodiesel can actually reduce CO2 levels in the atmosphere: growing soybeans consumes nearly four times as much CO2 as the amount of CO2 produced in the exhaust from soybean oil biodiesel.

Energy efficiency According to a comparative life­cycle study by the US Department of Energy's National Renewable Energy Laboratory, biodiesel requires only 0.31 units of fossil energy to make 1 unit of fuel. (An Overview of Biodiesel and Petroleum Diesel Life Cycles) http://www.ott.doe.gov/biofuels/docs/lifecycle.html

"By contrast, it takes 1.2 units of fossil resources to produce 1 unit of petroleum diesel," the study says.

We wonder what the energy efficiency figures for biodiesel would be if fossil fuels were eliminated from the equation and the entire production process powered by biofuels, from planting the seeds to filling the tank?

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Three choices There are at least three ways to run a diesel engine on bio­power, using vegetable oils, animal fats or both. All three work with both fresh and used oils.

• Use the waste oill just as it is ­­ usually called SVO fuel (straight vegetable oil); (means converting your car)

• Mix it with kerosene (paraffin) or diesel fuel, or with biodiesel; (can still clog injectors)

• Convert it to biodiesel. (Best choice and has worked for me for over 12 months)

The first two methods sound easiest, but, as so often in life, it's not quite that simple.

Biodiesel

Biodiesel has some clear advantages over SVO: it works in any diesel, without any conversion or modifications to the engine or the fuel system ­­ just put it in and go. It also has better cold­weather properties than SVO (but not as good as petro­diesel ­­ see Using biodiesel in winter). And, unlike SVO, it's backed by many long­term tests in many countries, including millions of miles on the road.

Biodiesel is a clean, safe, ready­to­use, alternative fuel, whereas it's fair to say that SVO systems are mostly still experimental and need further development.

On the other hand, biodiesel can be more expensive, depending what you make it from and whether you're comparing it with new or used oil (and where you live). And, unlike SVO, it has to be processed ­­ you have to make it. But the large and rapidly growing worldwide band of homebrewers don't seem to mind ­­ they make a supply every week or once a month and soon get used to it. Many have been doing it for years.

And anyway, you have to process SVO too, especially WVO (waste vegetable oil, used, cooked), which many people with SVO systems use because it's cheap or free for the taking. WVO has to be filtered and dewatered, and probably should be deacidified.

Biodieselers say, "Well, if I'm going to have to do all that I might just as well make biodiesel instead." But SVO types scoff at that ­­ it's much less processing than making biodiesel, they say. To each his own I prefer the fact that I can run it in my engine without modifying my vehicle.

x Needs processing

Guaranteed trouble­free

Engine conversion Cheaper

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Biodiesel Yes Yes No Sometimes SVO/WVO Less No Yes Usually

Costs and prices: Biodieselers using waste oil feedstock say they can make biodiesel for 60 cents US per gallon or less. Most people use about 600 gallons of fuel a year (about 10 gallons a week) ­­ say US$360 a year. An SVO system costs from $300 to $1,200 or more. So with an SVO system you'll be ahead in a year or two, which is not a long time in the life of a diesel motor. But will it last as long with SVO? Too soon to tell. Probably, if you use a good system.

Biodiesel Converting the oil to biodiesel is probably the best of the three options (or we think so anyway).

Most major European vehicle manufacturers now provide vehicle warranties covering the use of pure biodiesel ­­ though that might not be just any biodiesel. Some insist on "RME", rapeseed methyl esters, and won't cover soy biodiesel in the US, but this seems to be more a trade­related issue than a quality­control one. Germany has more than 1,500 filling stations supplying biodiesel, and it's cheaper than ordinary diesel fuel. It's widely used in France, the world's largest producer. Virtually all fossil diesel fuel sold in France contains between 2% and 5% biodiesel. New EU laws will soon require this Europe­wide. Some states in the US are legislating similar requirements. There's a growing number of US suppliers. Biodiesel is more expensive than ordinary diesel in the US but sales are rising very fast and prices will drop in time. In the UK biodiesel is taxed less than petrodiesel and it's available commercially.

But there's a lot to be said for the GREAT feeling of independence you'll get from making your own fuel (and it's more than just a feeling ­­ it's real!).

If you want to make it yourself, there are several good recipes available for making high­quality biodiesel, and they all say what we also say: some of these chemicals are dangerous, take full safety precautions, and if you burn/maim/blind/kill yourself or anyone else, that will make us very sad, but not liable ­­ we don't recommend anything, it's nobody's responsibility but your own.

On the other hand, a lot of people are doing it ­­ it's safe if you're careful and sensible. "Sensible" also mean not over­reacting, as some people do: "I'd like to make biodiesel but I'm frightened of all those terrible poisons." In fact they're common enough household chemicals. Lye is sold in supermarkets and hardware stores as a drain­cleaner, there's probably a can of it under the sink in most households. Methanol is the main or only ingredient in barbecue fuel or fondue fuel,

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sold in supermarkets and chain stores as "stove fuel" and used at the dinner table; it's also the main ingredient in the fuel kids use in their model aero engines. So get it in perspective, no need to be frightened. See Safety for further information. Learn as much as you can first ­­ lots of information is available. Make small test batches before you try large batches (see also Test­batch mini­processor). Make it with fresh oil before you try waste oil.

What's next? Learn. You have some decisions to make. It's all quite simple really, thousands of people are doing it, very few of them are chemists or technicians, and there's nothing a layman can't understand, and do, and do it well. But there is quite a lot to learn. You should find everything you need to know on the web or at this address

http://journeytoforever.org/biodiesel_make.html#biodnew#biodnew

Start off with the simplest process that has the best chance of success and move on step by step in a logical progression, adding more advanced features

The Process Vegetable oils and animal fats are triglycerides, containing glycerine. The biodiesel process turns the oils into esters, separating out the glycerine. The glycerine sinks to the bottom and the biodiesel floats on top and can be syphoned off.

The process is called transesterification, which substitutes alcohol for the glycerine in a chemical reaction, using lye as a catalyst.

We use methanol to make methyl esters. We'd rather use ethanol because most methanol comes from fossil fuels (though it can also be made from biomass, such as wood), while ethanol is plant­based and you can distill it yourself, but the biodiesel process is more complicated with ethanol. (See Ethyl esters.)

Ethanol (or ethyl alcohol, grain alcohol ­­ EtOH, C2H5OH) also goes by various other well­known names, such as whisky, vodka, gin, and so on, but methanol is a deadly poison: first it blinds you, then it kills you, and it doesn't take very much of it. It takes a couple of hours, and if you can get treatment fast enough you might survive. (But don't be put off ­­ it's easy to do this safely. Safety is built­in to everything you'll read here.)

Methanol is also called methyl alcohol, wood alcohol, wood naphtha, wood spirits, methyl hydrate (or "stove fuel"), carbinol, colonial spirits, Columbian spirits, Manhattan spirits, methylol, methyl hydroxide, hydroxymethane, monohydroxymethane, pyroxylic spirit, or MeOH (CH3OH or CH4O) ­­ all the same

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thing. (But, confusingly, "methylcarbinol" or "methyl carbinol" is used for both methanol and ethanol.) In the US you can usually get it at race tracks.

Methylated spirits (denatured alcohol) doesn't work; isopropyl alcohol (rubbing alcohol) also doesn't work.

The lye catalyst can be either sodium hydroxide (caustic soda, NaOH) or potassium hydroxide (KOH), which is easier to use, and it can provide a potash fertilizer as a by­product. Sodium hydroxide is often easier to get and it's cheaper to use. If you use potassium hydroxide, the process is the same, but you need to use 1.4 times as much. (See More about lye.) You can get KOH from soapmakers' suppliers and from chemicals suppliers. Other chemicals, such as isopropyl alcohol (isopropanol) for titration, are available from chemicals suppliers. CAUTION: Lye (both NaOH and KOH) is dangerous ­­ don't get it on your skin or in your eyes, don't breathe any fumes, keep the whole process away from food, and right away from children. Lye reacts with aluminum, tin and zinc. Use glass, enamel, stainless steel or HDPE (High­Density Polyethylene) containers for methoxide. (See Identifying plastics.)

Biodiesel from waste oil This is the most appealing answer but is more difficult.

First, check for water content. Used oil often has some water in it, and water in the oil will interfere with the lye, especially if you use too much lye, and you'll end up with jelly. Test first for water content ­­ heat half a litre or so in a saucepan on the stove and monitor the temperature with a thermometer. If there's water in it it will start to "snap, crackle and pop" by 50 deg C (120 deg F) or less. If it's still not crackling by 60 deg C (140 deg F) there's no need to dewater it.

Waste oil needs more catalyst than new oil to neutralize the Free Fatty Acids (FFAs) formed in cooking the oil, which interfere with the transesterification process.

You have to titrate the oil to determine the FFA content and how much lye will be required to neutralize it. This means determining the pH ­­ the acid­alkaline level (pH7 is neutral, lower values are increasingly acidic, higher than 7 is alkaline). An electronic pH meter is best, but you can also use pH test strips (or litmus paper), or phenolphthalein solution (from a chemicals supplier).

Dissolve 1 gm of lye in 1 litre of distilled water (0.1% lye solution). In a smaller

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beaker, dissolve 1 ml of the cooled oil in 10 ml of pure isopropyl alcohol. Warm the beaker gently by standing it in some hot water, stir until all the oil dissolves in the alcohol and turns clear. Add 2 drops of phenolphthalein solution.

Using a graduated syringe, add 0.1% lye solution drop by drop to the oil­alcohol­ phenolphthalein solution, stirring all the time, until the solution starts to turn pink and stays that way for 10 seconds. Take the number of millilitres of 0.1% lye solution you used and add 3.5. This is the number of grams of lye you'll need per litre of oil.

First titration took 6 ml of 0.1% lye solution(not very good oil), so we used 6 + 3.5 = 9.5 grams of lye per litre of oil: 95 grams for 10 litres.

Then proceed as with new oil: measure out the lye and mix it with the methanol to make sodium methoxide ­­ it will get even hotter and take longer to mix, as there's more lye this time. Make sure the lye is completely dissolved in the methanol.

Carefully add the sodium methoxide to the warmed oil while stirring, and mix for an hour. Settle overnight, then syphon off the biodiesel.

Washing Biodiesel should be washed to remove soap, catalyst and other impurities. Some people insist on it, others don't and argue that the small amounts of impurities cause no engine damage.

We recommend washing it. In fact we insist on it ­­ good­quality biodiesel must be washed.”

Right this is where I’m going to jump in, water washing is a 2 edged sword if you use water washing firstly you are removing soaps etc which is good but you are adding time and moisture to your fuel which is bad and a pain as you have to then dry it by gentle heating or settling for a long time.

Personally I use it unwashed and have had no issues as it filtered down to one micron before it goes in my tank. I’m currently playing with dry washing and water washing in combination and this is producing some excellent result buts but more about that on the www.gobionz.com website when it’s finished. http://www.gobionz.com

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Using biodiesel You don't have to convert the engine to run it on biodiesel, but you do need to make some adjustments and check a few things.

Petro­diesel leaves a lot of dirt in the tank and the fuel system. Biodiesel is a good solvent ­­ it tends to free the dirt and clean it out. Be sure to check the fuel filters regularly at first. Start off with a new fuel filter.

Check there are no natural rubber parts in the fuel system. If there are, replace them. Viton is best.

See Biodiesel and your vehicle

Safety

Wear proper protective gloves, apron, and eye protection and do not inhale any vapors. Methanol can cause blindness and death, and you don't even have to drink it, it's absorbed through the skin. Sodium hydroxide can cause severe burns and death. Together these two chemicals form sodium methoxide. This is an extremely caustic chemical. These are dangerous chemicals ­­ treat them as such! Gloves should be chemical­proof with cuffs that can be pulled up over long sleeves ­­ no shorts or sandals. Always have running water handy when working with them. The workspace must be thoroughly ventilated. No children or pets allowed.

Organic vapor cartridge respirators are more or less useless against methanol vapors. Professional advice is not to use organic vapor cartridges for longer than a few hours maximum, or not to use them at all. Only a supplied­air system will do (SCBA ­­ Self­Contained Breathing Apparatus).

The best advice is not to expose yourself to the fumes in the first place. The main danger is when the methanol is hot ­­ when it's cold or at "room temperature" it fumes very little, and this is easily avoided. Don't use "open" reactors ­­ biodiesel processors should be closed to the atmosphere, with no fumes escaping. All methanol containers should be kept tightly closed anyway to prevent water absorption from the air.

We transfer methanol from its container to the methoxide mixing container by pumping it, with no exposure at all. This is easily arranged, and an ordinary aquarium air­pump will do (the same one you use for washing the biodiesel). The methoxide is mixed like this ­­ Methoxide the easy way, which also happens to be the safe way. The mixture gets quite hot at first, but the container is kept closed and no fumes escape. When mixed, the methoxide is again pumped into the (closed)

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biodiesel processor with the aquarium air­pump ­­ there's no exposure to fumes, and it's added slowly, which is optimal for the process and also for safety.

Once again, making biodiesel is safe if you're careful and sensible. "Sensible" also mean not over­reacting, as some people do: "I'd like to make biodiesel but I'm frightened of all those terrible poisons." In fact they're common enough household chemicals. Lye is sold in supermarkets and hardware stores as a drain­cleaner, there's probably a can of it under the sink in most households. Methanol is the main or only ingredient in barbecue fuel or fondue fuel, sold in supermarkets and chain stores as "stove fuel" and used at the dinner table; it's also the main ingredient in the fuel kids use in their model aero engines. So get it in perspective: be careful with these chemicals ­­ with ALL chemicals ­­ but there's no need to be frightened of them.”

OK had enough reading? The next part I’ll cover the “Building a Reactor” part and list some of the things I have done and where I’m planning to go with my reactor.

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How tobuild your first Biodiesel reactor OK now the really fun bit Right, there are many ways to approach this but there are 2 designs that stand out for simplicity and the first (and my favorite as it recycles old drums) is this one.

These specs for reactors are guidelines as everyone has there own ideas. So take what you need from them and add them to your own designs.

I did I have a very weird set­up that is similar but again different from both. It depends on what you have at hand and how much time and money you can invest!

Read this first http://journeytoforever.org/biodiesel_processor.html#intro

“How to make a cone­bottomed processor” Maybe the best thing (the only good thing?) about fossil­fuel petroleum is that it comes in 55­gallon oil drums, which duly become empty, and magically transform themselves into the worldwide mainstay of appropriate technology and do­it­ yourself tinkering. And of backyard biodiesel­making ­­ the perfect mixing vessel.

Well, almost perfect. They need a bottom drain, and for perfection the drain should be at the end of a cone, replacing the flat bottom of the drum.

Here's how to make a cone bottom for your 55­gal oil drum biodiesel mixer.

You need cutting gear to cut out the drum bottom and cut the cone to shape from a piece of flat steel sheeting, and welding equipment to join up the cone and weld it to the bottom edge of the drum.

The problems tend to arise when drawing out the shape of the cone­to­be on flat steel. Trial­and­error doesn't work very well, usually leading to a lot of annoying grinding to make it fit, or a botched job, wasted steel and wasted time and effort. This is how to get it right.

You'll also need a calculator and a big compass.

Mike Pelly's cone­bottomed 55­gal drum reactor

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If you don't have a compass big enough to draw the circle you'll need, you can improvise one from a steel nail, a felt­tip marker pen and some cord that won't stretch, or better, thin wire. Coil the wire tightly round the nail at one end and round the pen at the other, close to the point in both cases, with the length of wire between them equal to the radius of the circle you're going to draw. Take some trouble trying to get it precisely the right length ­­ holding it all in place then turning the pen so that you coil a little more or a little less wire round it works well. Make a little dent with a centre­punch in the centre of the steel sheeting for the point of the nail, then carefully draw your circle, holding both pen and nail firmly vertical.

Use 16­ or 18­gauge flat steel for the cone. A 3/4", 7/8" or 1" valve will be fine.

(Drawing not to scale.)

You can adapt this method to any size of drum just by changing the measurements and calculating accordingly.

The outer­edge diameter of a standard 55­gallon drum is 22­3/4 inches ­­ check it,

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this is the critical measurement.

How deep do you want your cone? The deeper the better, because the deeper it is the steeper will be the sides, and the better it will drain. If it's 12" deep, the sides of the cone will have a slope of just over 45 degrees, not very steep. At 15" deep the slope is about 52 degrees, steeper. But deeper and steeper also means the whole contraption will be higher. The drum is nearly 3ft high, plus 15" for the cone, plus another couple of inches for the valve, a couple more for a hose connection, and you need enough space to put a bucket underneath ­­ another 12" at least... that's 65" already, up to your chin if you're a six­footer.

So we've taken a 12"­deep cone as an example. That's the second critical measurement.

In the diagram, "r" is the radius of the oil drum bottom, measured to the outer edge ­­ that's half the diameter, 22.75 ÷ 2 = 11.375".

h = 12" ­­ "h" is the height (depth) of the cone.

sh = 16.535" ­­ "sh" is the "slant height" of the cone, the length of the sloping side.

You calculate this by Pythagoras's theorem, which states that the square on the hypotenuse of a right­angled triangle is equal to the sum of the squares on the other two sides.

If you're among the math­challenged, relax, it's easy ­­ your calculator will do the work for you.

The red triangle in the diagram is a right­angled triangle ­­ the angle between the two sides "r" and "h" is a right­angle, 90 degrees. The side opposite the right angle is "sh", the slant height of the cone, and that's the hypotenuse. To calculate its length, square the other two sides. That means multiply 12 x 12 = 144; multiply 11.375 x 11.375 = 129.390625. Add the two answers together: 144 + 129.390625 = 273.390625. That's the "sum of the squares on the other two sides", which equals the square on the hypotenuse. So the square root ­­ on the calculator ­­ of 273.390625 is the length of the hypotenuse: 273.390625 = 16.53452827. Shorten it to three decimal places (add one if the fourth figure is 5 or more) = 16.535". That's the slant height of your 12" deep cone ­­ the third critical measurement.

To make a cone all you have to do is draw a circle on something flat, cut a pie­slice out of it and join up the two straight edges. But if you want the bottom of the cone to fit something specific, and for it to be a particular height, you have to know how big to draw the circle, and how big to make the pie­slice.

The radius of the cone circle you have to draw is the same as the slant height of the

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cone ­­ sh, 16.535".

So now you know the size of the piece of flat steel sheeting you'll need: 16.535 x 2 = 33.07" square. So make it 3ft square.

Take a long rule, or anything with a straight edge that's long enough, and draw a line across the plate from one corner to the opposite corner, and a second line joining the other two corners. Where they cross is the centre of the plate. Draw your circle from that point, radius 16.535". Okay, so you can't measure .535" on your ruler. It comes to 17/32", but 9/16" will do; 5/8" will also do, or make it 16­11/16", which will give you a small margin of error.

Parts of a circle

Now you need to know how big to make the pie­slice cut­out.

The edge of the cone must fit the drum. So the cone circle minus the pie­slice must match the circumference of the outer edge of the bottom of the drum. Circumference = diameter x pie ­­ that's on your calculator, or just multiply by 22 and divide the answer by 7.

The diameter of the drum is 22.75", circumference is 22.75 x = 71.5".

The diameter of the cone circle is 16.535 x 2 = 33.07, circumference is 33.07 x = 103.934".

The arc (a section of the circumference) of the cut­out pie­slice sector is 103.934 ­ 71.5 = 32.434".

Now you need to know the angle of the cut­out sector so you can measure it off with a protractor. Divide the arc by the circumference and multiply by 360: 32.434 ÷ 103.934 x 360 = 112.34 degrees. Make it 112­1/3 degrees.

Now you can draw in your pie­slice that you're going to cut out. Here's a protractor you can print out if you don't have one.

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Useful to know: the volume of a cone is 1/3 r 2 h. For a 12" cone on a 55­gal drum, that's 7 gallons (US).

Two more things to consider: first, you might want to leave a tab for some overlap when welding the two edges of the cone together, as marked by the dotted line on one edge of the pie­slice in the diagram.

Second, you might want to pre­cut a hole for the valve, as in the diagram. Or just saw off the point of the cone at the right height after it's assembled. Depending on what kind of valve you get, you'll either weld the valve on direct, or it will screw onto a short length of steel pipe, and you'll weld the steel pipe on. Whichever, stand the valve or pipe on top of the cone, straight up, and draw a line under it around the top of the cone where you'll make the cut. Make sure the hole is narrower than the outside diameter of the pipe/valve so you'll have something to weld it onto.

If you'd rather pre­cut the hole, measure the ID (inside diameter) of the pipe or valve, add half the thickness of the pipe or valve wall. Say the answer is 7/8". All the angles are the same as for calculating the cone, so you can do it proportionately: 7/8" is the diameter of the hole, divide by 2 for the radius: 7/16 = 0.4375. It's the slant height you want: 16.535 x 0.4375 ÷ 11.375 = 0.636", which is slightly more than 5/8", so make it 5/8". Draw the circle for the pre­cut hole for the valve with a radius of 5/8".

Before you start cutting and welding, double­check all your calculations and measurements. When you're satisfied, make your cuts, then weld it all up and you're done. You'll find it a lot easier to bend the cone evenly to shape if you use a roller of some kind. This is actually a good reason for pre­cutting the valve hole because the roller can fit through the hole while you're rolling it. Try a piece of 7/8" steel waterpipe about two feet long or more.

You'll also need a stand for it. Steel piping or angle iron will do, four legs, firmly welded to the sides of the oil drum and joined by cross­struts just above the level of the valve. Make it strong ­­ a full processor will weigh more than 400 lbs.

A useful refinement is a sight­tube, leading from near the bottom of the cone vertically up the side to near the top of the drum. Use translucent PEX tubing (crosslinked polyethylene) or high­density polyethylene (HDPE), thin­walled for better visibility, both of which are heat­ and chemical­resistant; 1/2" or more ID, preferably more. Get right­angled plumbing fittings, drill holes for them and weld them in. Use strong stainless­steel gem clips to connect the hose to the fittings, a good idea to use two clips at each end, with heat­ and chemical­proof silicon sealer as a gasket compound.”

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Once you’ve done all this just add you circulating/ mixing pump and extra pipes to give you a closed mixing system. I prefer pumps to mechanical mixing but it’s your reactor.

This next one is very similar to my current reactor but with some mods of my own. I used a double skinned plastic 44 Gallon drum as it was easier to work with than steel and has proved to be tough and reliable. I’ll put pictures on the website soon www.gobionz.com

The next one is from the http://www.biodieselcommunity.org/gettingstarted/ website remember this design shouldn’t be done as is , just use it as a general outline for your own ideas. This could be better if the draw was from the bottom and a better pump was used but again it’s up to you to try what works.

This design is also “Open Source” so please make sure if you copy the text below you include the authors details.

An old water heater tank can be adapted to make a safe and inexpensive biodiesel homebrewing apparatus. An HDPE carboy (white jug in photo) or other tank can become a passive small­scale methanol­catalyst mixer, and an inexpensive centrifugal pump (blue motor in photo) from Harbor Freight tools mixes the two liquids to enable the biodiesel reaction to take place. After a day of settling, the glycerol byproduct can be drained out fairly well­ the tanks have a wine­bottle­bottom

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profile, with a drain at the 'pointed' edge, so separation of two liquids can be reasonably clean. The processor costs about $150 in plumbing and electrical, and about a day or less of work. The tank can be an ancient lime­crusted one scavenged from a dump, or can be bought new for about $200 more.

After draining off glycerol, the same mixing pump can transfer the biodiesel to a 'wash tank' for a water wash to remove methanol and water­soluble impurities. There's an extremely simple 'standpipe' design which requires no welding, which makes a nice minimal tank, the Sean Parks' Standpipe Wash Tank. The standpipe wash tank costs about $30 in plumbing to build. People have built variations which include heating, ways to use plastic barrels, and build­in mistwash heads (which only works for smaller batches).

This system has developed a huge following in the biodiesel community, and there are hundreds of homebrewers who have built or built and modified theirs.

below: Sean Parks' Standpipe Wash Tank

Plans for building the Appleseed:

there are many possible plumbing variations. Here's the bare­bones original and a parts list, and several variations. Please note that until recently I had an outdated

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diagram here which you may still find references to on the Web. It's now corrected and so is the parts list:

simplest plans

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Here's how I now build these, to wrap around the tank slightly (temperature gauge not shown)

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To the right and below are a couple of variations: separate sight tube and extra valves on each tube (I now consider these valves unnecessary)

here is the plumbing for my 'bells and whistles' variation, with the temperature gauge shown in original packaging. Temperature gauge numbers MUST start at 100F or lower, not 130F.

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I purchase the valves at Harbor Freight Tools, where they cost considerably less than Home Depot and other places. Lowes' is my preferred big box hardware for the plumbing. Local stores like Ace or True Value can be cheap or can be very expensive for plumbing, at random. Home Depot is my last choice­ their plumbing section is usually very disorganized and prices are high. Avoid at all costs.

Harbor Freight runs sales on their online or retail stores every few months­ so pumps may end up costing about $25 and 3/4" ball valves can be $2 when on sale. valves will bankrupt you on this project­ shop around. They range from $6 at Lowes to $12 at some local stores I"ve patronized, and you'll need lots of them.

Shopping List and General Instructions:

(note: all plumbing 3/4 inch unless otherwise noted. All plumbing black iron threaded pipe if possible­ galvanized is sometimes the only choice for some fittings but is not preferred due to zinc content):

The modifications needed to an electric water heater are:

Remove dip tube (?) from the top cold water inlet. Dip tubes are underneath any pipes or pipe nipples threaded into the heater. This is the worst part of the operation­ undoing any old piping. If it is a two­heating element water heater you might also need to disable the upper element and thermostat­ the upper element is usually above the level of the oil you are heating, and would burn out if heated without being covered by liquid. You will also probably also want to mount the water heater on a stand­ I use two milk crates stacked together­ and strap it to the wall studs for earthquake safety in earthquake country. I usually disable the upper heating element and thermostat in a two­thermostat water heater processor­ because the upper heating element will be above the level of the oil you’re heating.

Parts List: All plumbing 3/4 inch unless otherwise noted. All plumbing black iron threaded

pipe if possible­ galvanized is sometimes the only choice for some fittings but is not preferred due to zinc content:

A. 3" pipe nipple B. 3/4" x 3/4" x 1/2" tee C close nipples ­ you'll need 7 of them D ball valves (3/4")­ buy 5 of them (very cheap at Harbor Freight, more expensive elsewhere) E cross fitting (a sort of four­way tee, available at Lowes' but not at all other hardware stores. Substitute a pair of tees and some close nipples if you cant' find

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one) F. Bushing: 3/4" by 1/2"­ buy 2 G. 1/2" close nipple­ 2 H 1/2" ball valve H2 1/2" swing check valve I. Nylon or Brass 90degree thread­to­barb fitting: male thread end is 1/2" thread, hose barb end is 3/8" barb, plus hose clamp J. Length of 3/8" vinyl tubing­ 3 or 4 feet. K. straight or 90 degree 1/2 inch threaded to 3/8 inch barbed nylon or brass fitting, and hose clamp L. 3/4" Hose Barb (I use plastic grey PVC ones that are sometimes in irrigation departments for about 30 cents each) M. 1 or 2 feet of vinyl tubing as a drain/filler tube. Make this clear rather than braided hose so you can see through it well. N. Union (3/4" of course) O 1" by 3/4" bushings­ 2 . Thread these into the pump with TONS of thread tape or pipe dope­ more than you would normally use. The pump threads are straight thread rather than tapered American pipe thread, so they need extra help to prevent leaks. P. Length of BRAIDED 3/4" vinyl hose. Do not use unreinforced nonbraided hose here. Prepare to replace this hose every few months as it deteriorates with heat and biodiesel. Q 90degree elbows­2 R. length of pipe nipple approx 12"­ 18" (purchase correct size after assembling everything else) S. 2" long pipe nipple­ 2 T Automotive mechanical temperature gauge (not 12V electrical type). I prefer the heavy­duty Sunpro one from Pep Boys over the other brands/stores. It should be $15ish. The numbers should start at 100F or lower instead of 130F (the other option at these stores). The biodiesel homebrew supply stores sell some alternatives. U. Proper plumbing to attach to water heater's pressure relief vent and direct any fumes outside if using a pressure relief. V. Water heater strapping, or other earthquake strapping for attaching the processor to your wall studs. I use webbing strapping. W. Pump: This is a '1" Clear Water Pump from Harbor Freight Tools or Northern Tool­ $35 part number 1479. This centrifugal pump also allows your 3/4" hose become sight tube (so you know how high the oil level is when filling the processor). Non­centrifugal pumps won't give you this feature, in which case you will need to instead add a tee and another tube as sight tube Give the sight tube a shutoff valve so you don't drain unreacted oil into your biodiesel when emptying the processor. See other plans elsewhere in this book for more details on how this works. You will need to buy a grounded plug and a length of 14gauge power tool cord to wire up the pump as well. X Heating elements and thermostats: Disable the upper heating element and thermostat.

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Disconnect power from the water heater before opening it’s electrical panels! I turn 220Volt water heaters into 110 volts and add a heavy­duty 110V plug on a 12 or 10 gauge cord, because we don t usually have 220V outlets easily accessible at the sites where I work. A 220V heating element operated at 110V will put out 1/4 the power output (watts). In practice this usually means that the lower element will heat far too slowly on 110. I purchase a 110V replacement element instead. Thermostats will work at either voltage

(c) design 2003 Maria Alovert, published in Biodiesel Homebrew Guide, Nov 2003 edition

This is my favorite at http://home.swbell.net/scrof/Biod_Proc.html

It includes filters and vacuum filling through the filters and methanol collection, very efficient. I think this is the way to go. Automate this and you’re on a winner.

Once you get going it’s really only limited to your imagination and budget but once you have got your head around the process requirements then the more innovative the better.

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If you want to really go for it then OFR or Oscillatory Flow Reactors are the key and mean you can process to your hearts content with a constant flow reactor meaning that is just keeps producing as long as you feed it ingredients.

Oscillatory Flow Mixing (OFM) provides highly effective mixing in tube reactors by the combination of fluid oscillations and baffle inserts ... OFM is particularly suited to continuous processing. How it works, Research, Technology, Publications, and more, with diagrams and photographs. http://www.cheng.cam.ac.uk/ research/groups/polymer/OFM/

Solid Catalyst reactors are coming to the fore recently and some more info can be found here.

http://www.greencarcongress.com/2005/08/new_biodiesel_p.html

This is an interesting story about a credit card reactor needing no catalyst just alcohol

http://www.tbo.com/news/money/MGBWHTJE8ME.html

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Making Biodiesel

Ingredients

SAFETY

SAFETY SAFETY

Wear proper protective gloves, apron, and eye protection and do not inhale any vapors. Methanol can cause blindness and death, and you don't even have to drink it, it's absorbed through the skin. Sodium hydroxide can cause severe burns and death. Together these two chemicals form sodium methoxide. This is an extremely caustic chemical. These are dangerous chemicals ­­ treat them as such!

Always have a hose running when working with them. The workspace must be thoroughly ventilated. No children or pets allowed.

Mixture: Waste vegetable oil (WVO) ­­ used cooking oil, fryer grease, animal fats, lard Methanol (CH3OH) ­­ 99%+ pure Sodium hydroxide (NaOH ­­ caustic soda, lye) ­­ must be dry

Titration: Isopropyl alcohol (rubbing alcohol) ­­ 99%+ pure Distilled water Phenolphthalein solution (not more than a year old, kept protected from strong light) ­­ "Phenol" or "Phenol Red" from swimming pool or hot tub supply stores may not be the same as phenolphthalein; it can be used but the directions for use may be different

Washing: Vinegar Water (Or Dry wash with more research)

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Procedure

1. Filter WVO to remove any food scraps or solid particles. 2. Heat WVO to remove any water content (optional). 3. Perform titration to determine how much catalyst is needed. 4. Prepare sodium methoxide. 5. Heat WVO, mix in the sodium methoxide while stirring. 6. Allow to settle, remove the glycerine. 7. Wash and dry. (this is optional in my opinion as long as you filter and stand

for long enough but it’s up to you) 8. Check quality.

This procedure is called transesterification, similar to saponification. Sound familiar? Saponification is soap making. To make soap you take a transfatty acid or triglyceride (oil or kitchen grease) and blend it with a solution of sodium hydroxide (NaOH, caustic soda or lye) and water. This reaction causes the ester chains to separate from the glycerine. These ester chains are what becomes the soap. They're also called lipids. Their unique characteristic of being attracted to polar molecules such as water on one end and to non­polar molecules like oil on the other end is what makes them effective as soap.

In transesterification, lye and methanol are mixed to create sodium methoxide (Na+ CH3O­). When mixed in with the WVO this strong polar­bonded chemical breaks the transfatty acid into glycerine and also ester chains (biodiesel), along with some soap if you're not careful (more on that later). The esters become methyl esters. They would be ethyl esters if reacted with booze (ethanol) instead of methanol.

Figures 1­3 show these two reactions. The zigzag lines in the triglyceride diagram (Figure 1) are shorthand for carbon chains. At both ends of each line segment is a carbon atom.

Figure 1

In Figures 2 and 3 these zigzags are shorthanded as R1, 2 and 3.

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Figure 2

Figure 3

1. Filtering

Filter the WVO to remove food particles. You may have to warm it up a bit first to get it to run freely, 95 deg F (35 deg C) should be enough. Use a double layer of cheesecloth in a funnel, or a restaurant or canteen­type coffee filter.

(The better you can filter it now the better your reaction will be later)

2. Removing the water

Many people heat the WVO first to remove any water content. Waste oil will probably contain water, which can slow down the reaction and cause saponification (soap formation). The less water in the WVO the better.

This is how they do it. Raise the temperature to 212 deg F (100 deg C), hold it there and allow any water to boil off. Use the mixer to avoid steam pockets forming below the oil and exploding, splashing hot oil out of the container. Or drain water puddles out from the bottom as they form ­­ you can save any oil that comes out with the water later. (I’m more on the side of 70 or less as this will still remove water without creating to many more FFA’s)

When boiling slows, raise the temperature to 265 deg F (130 deg C) for 10 minutes. Remove heat and allow to cool.

You may be lucky and find a regular source of WVO that doesn't need to have the water boiled off, in which case don't do it ­­ boiling means extra energy and time.

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Personally I don't boil off the water first, I'd rather avoid the extra step in the process and save the energy it uses. But unless you're sure, it may be better to be on the safe side.

3. Titration

To determine the correct amount of lye required, a titration must be performed on the oil being transesterified. This is the most difficult step in the process, and the most critical ­­ make your titration as accurate as possible.

IMPORTANT: The lye must be dry ­­ keep it away from water, store it in an airtight container.

Make up a solution of one gram of lye to one liter of distilled water. Make sure it dissolves completely. This sample is then used as a reference tester for the titration process. It's important not to let the sample get contaminated, it can be used for many titrations.

Mix 10 milliliters of isopropyl alcohol in a small container with a 1 milliliter sample of WVO ­­ make sure it's exactly 1 milliliter. Take the WVO titration sample from the reaction vessel (Figure 5 #1) after it's been warmed up and stirred.

Add to this solution 2 drops of phenolphthalein, an acid­base indicator that's colorless in acid and red in base.

IMPORTANT: Phenolphthalein has a shelf life of about a year, it is very sensitive to degradation by light so after a while it will start giving erroneous readings.

Using a graduated eye dropper (with increments marked in tenths of milliliters) or some other calibrated instrument (from medical supply outlets), while carefully keeping track of the amounts, drop measured amounts of the lye/water solution a couple of tenths of milliliters at a time into the WVO/isopropyl/phenolphthalein solution.

Follow each drop with vigorous stirring of the solution. In cold weather the WVO might congeal and not work so you might need to do the titration in a heated room. If conditions are right eventually the solution turns pink (magenta), and stays pink for 10 seconds. This is the indicator color for a pH range of 8­9 (see the photograph in the left column of this page, "Color of titrated liquid sample when at the correct pH"). It's important to find the exact amount, to just reach this pH without dropping in too much!

It's a good idea to do this entire process more than once to ensure that your number is correct. I've found that depending on the type of WVO, how hot it got in the fryer, what was cooked in it and how long it was used, the amount of lye/water solution

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needed to titrate it is usually 1.5 to 3 milliliters. You can also use litmus paper or a digital pH tester instead of the phenolphthalein. Try it with fresh cooking oil from your kitchen too, it should need much less lye to reach pH 8­9.

The calculation

The next step is to determine the amount of lye needed for the reaction. Take the number of milliliters derived from the titration and multiply by the number of liters of WVO to be transesterified.

There is one more thing to be included in the calculation. Every liter of neat vegetable oil (fresh ­­ never been cooked) needs 3.5 grams of lye for the reaction. So for every liter of WVO to be transesterified add an additional 3.5 grams of lye.

Example: The titration determined that it took 2.4 milliliters to reach pH 8­9 and you'll be transesterifying 150 liters of oil.

2.4 grams times 150 liters equals 360 grams lye

Plus 3.5 grams times 150 liters equals 525 grams lye

360 + 525 = 885 grams lye

If the titration result was 1.8 milliliters to reach pH 8­9, the final amount of lye needed for the reaction would be 795 grams.

I've found over time that the number of grams of lye needed per liter of WVO has generally been between 6 and 7.

Test batches (REALLY IMPORTANT)make sure you do test batches first. The first few times you do this process or if you're planning on transesterifying a lot of WVO it is a good practice to first try out your lye amounts on a 1 liter batch in a kitchen blender.(Remember the one from earlier) This works really well and you don't need to heat up the WVO too much, just enough so it will spin well in the blender. Blenders are very thorough at mixing the ingredients so heating is not as critical.

Start by mixing up the lye and methanol in a blender (one that will never be used for food again). First make sure the blender and all utensils used are dry. Forming the exothermal sodium methoxide polar molecule will heat up the blender container a bit. Keep mixing until all the lye has been dissolved.

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Once the sodium methoxide is prepared, add to the blender 1 liter of WVO. Make certain all your weights and volumes are precise. If you're unsure of the titration result numbers then use 6­6.25 grams of lye per liter of used WVO, or 3.5 grams for fresh vegetable oil. Blender batches need only be run for about 15­20 minutes for separation to be completed before switching off. The settling takes some time to complete. The solution can be poured from the blender into another container right after switching off the blender.

It is good to do a few batches with varying amounts of lye recorded so later when checking results one can choose the lye quantity that did the best job.

When too much lye is used the result can be a troublesome gel that is tough to do anything with. (See Glop soap This can be recovered but it’s a only worth it if you end up with alot.) When not enough lye is used the reaction does not go far enough so some unreacted WVO will be mixed with the biodiesel and glycerine. This will form three levels with biodiesel on top above unreacted WVO with glycerine on the bottom. If there is too much water in the WVO it will form soaps and settle right above the glycerine forming a fourth level in the container. This layer is not too easy to separate from the unreacted WVO and glycerine layers.

4. Preparing the sodium methoxide

Generally the amount of methanol needed is 20% of the WVO by mass. The densities of these two liquids are fairly close so measuring 20% of methanol by volume should be about right. To be completely sure, measure out a half­liter of both fluids, weigh, and calculate exactly what 20% by mass is. Different WVOs can have different densities depending on what type of oil it originally was and how long it was used in the deep fryer.

Example: When transesterifying 100 liters of WVO, use 20 liters of methanol.

The methanol is mixed into a solution with the sodium hydroxide (lye), creating sodium methoxide in an exothermic reaction (ie it gets warm from bonds forming). Keep all utensils the lye comes in contact with as dry as possible.

CAUTION: Treat sodium methoxide with extreme caution! Do not inhale any vapors! If any sodium methoxide gets splashed on your skin, it will burn you without your feeling it (killing the nerves) ­­ wash immediately with lots of water. Always have a hose running when working with sodium methoxide.

Sodium methoxide is also very corrosive to paints. Lye reacts with aluminum, tin and zinc. Use glass, enamel or stainless steel containers ­­ stainless steel is best. Used restaurant equipment supply stores and scrap metal recycling yards are two good

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places to look for this type of equipment. Braze on plumbing fittings for drains, etc. where needed.

5. Heating and mixing

Pre­heat waste vegetable oil reclaimed from a restaurant's waste grease barrel to 120­130 deg F (48­54 deg C).

A propeller or paint stirrer coupled to a 1/2­inch electric drill held securely in a jig works fine as a mixer.

Too much agitation causes splashing and bubbles through vortexing and reduces mix efficiency. There should be a vortex just appearing on the surface. Adjust the speed, or the pitch or size of the stirrer to get the right effect.

If you want a quieter processor, an electric pump plumbed to form a mixing loop for stirring the WVO would do a nice job. Mount the pump above the level that glycerine will gel at to prevent clogging up the pump (see below).

Add the sodium methoxide to the WVO while stirring; stir the mixture for 50 minutes to an hour. The reaction is often complete in 30 minutes, but longer is better.

The transesterification process separates the methyl esters from the glycerine. The CH3O of the methanol then caps off the ester chains and OH from the NaOH (lye) stabilizes the glycerine.

6. Settling and separation

Allow the solution to sit and cool for at least eight hours, preferably longer. The methyl esters ­­ biodiesel ­­ will be floating on top while the denser glycerine will have congealed on the bottom of the container forming a hard gelatinous mass (the mixing pump must be mounted above this level).

An alternative method is to allow the reactants to sit for at least an hour after mixing while keeping the brew above 100 deg F (38 deg C), which keeps the glycerine semi­liquid (it solidifies below 100 deg F). Then carefully decant the biodiesel.

This can be done by draining the reactants out of the bottom of the container through a transparent hose. The semi­liquid glycerine has a dark brown color; the biodiesel is honey­colored. Keep a watch on what flows through the sight tube: when the lighter­ colored biodiesel appears divert it to a separate container. If any biodiesel stays with the glycerine it is easy to retrieve it later once the glycerine has solidified.

If you left the mixture in the tank until the glycerine gelled, reheat the tank just

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enough to liquify the glycerine again. Don't stir it! Then decant it out as above.

A proposed alternative using very little electricity is illustrated in Figure 6. This system would use a furnace­type burner run on reclaimed esters to heat its reaction vessel. The vessel's stirring action is created by thermo inversion currents generated by the vessel's external cooling tubes and a baffled exhaust vent that runs up through its center.

Figure 5 also shows a blender (#3) used to mix up the sodium methoxide. When making 16 liter (5 gal) batches, I use a yard­ sale glass blender for the sodium methoxide solution (and for nothing else!), but I can't fit it all in at once, so I measure out three separate portions.

Glycerine The glycerine from WVO is brown and usually turns to a solid below about 100 deg F (38 deg C). Glycerine from fresh oil often stays a liquid at lower temperatures.

Reclaimed glycerine can be composted after being vented for three weeks to allow residual methanol to evaporate off or after heating it to 150 deg F (66 deg C) to boil off any methanol content (the boiling point of methanol is 148.5 deg F, 64.7 deg C). The excess methanol can be recovered for re­use when boiled off if you run the vapors through a condenser.

Another way of disposing of the glycerine, though a great bit more complicated, would be to separate its components, mostly methanol, pure glycerine (a valuable product for medicines, tinctures, hand lotions, dried plant arrangements and many other uses ­­ see Glycerine) and wax. This is often accomplished by distilling it, but glycerine has a high boiling point even under high vacuum so this method is difficult.

I was able to find someone who could use my glycerine (for dried flower arrangements) through the Industrial Materials Exchange (IMEX) in Seattle. IMEX has a publication that comes out every other month with listings, looking for and offering all types of surplus industrial materials. Many areas have similar exchanges. http://www.metrokc.gov/hazwaste/imex/

The glycerine by­product makes an excellent industrial­type degreaser/soap. One way to purify it is heat it to 150 deg F (65.5 deg C) to boil off excess methanol, making it safe for skin contact (take precautions with fumes). Once the glycerine is

Figure 6

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back to a liquid the impurities sink to the bottom and the color will become a more uniform dark brown. This can be cut with water leaving it a tan color, less concentrated and softer and easier to handle when washing hands. Produced this way the degreaser could be sold in squeeze or pump dispensers.

Other ideas for disposing of the glycerine are breaking it down to usable methane gas, with a methane digester or, for a much wilder idea, it could be broken down with pyrolisis. Pyrolisis was used extensively to run cars on firewood in oil­scarce Europe and elsewhere during World War 2. The processor has a heat source that heats the fuel (wood or glycerine) in an airtight box without oxygen. This allows the fuel to release its methane while not allowing it to burn. The methane is trapped in an inflatable storage container or compressed into a tank. This is an area of biodiesel development that warrants further work.

Soap residue

Suspended in the biodiesel will also be some soapy residues. These are the result of Na+ ions from the sodium hydroxide (NaOH) reacting with water created when the methanol bonds with the ester chains along with any other water that was suspended in the WVO.

If the reaction produces more than the usual amount of soap, this happens when lye comes into contact with water before it has a chance to react with the WVO ­­ in this case the excess water should have been boiled off first. (See Step 2, above, Removing the water.)

The part of the process where it's vital to keep all water out of the reaction is when making the sodium methoxide. Keep the blender and all utensils the lye comes in contact with as dry as possible. The chances of a good clean splitting of esters from glycerine with little soap by­product are much better on a warm dry summer day than on a damp winter day.

7. Washing and drying

There is more than one school of thought on getting the biodiesel from this stage to the fuel tank. One is to let it sit for a while (about a week), allowing the majority of the soap residues to settle before running the biodiesel through a filtration system then into the vehicle/home fuel tank.

Another method is to wash the soaps out of the fuel with water, one or more times. When washing biodiesel the first time it's best to add a small amount of acetic acid (vinegar) before adding the water. The acetic acid brings the pH of the solution closer to neutral because it neutralizes and drops out any lye suspended in the biodiesel.

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Figure 7 shows a simple way of washing using a translucent PVC type container with a valve 3­4 inches from bottom. For 5 gallon batches use those 5­7 gallon buckets found everywhere these days. If a translucent container can't be found one fabricated with a sight tube (#6) ought to work.

Fill with water until it is halfway between the container's bottom and the valve, then fill up with the biodiesel to be washed. After a gentle stirring (keep it gentle, you don't want to agitate up soaps) followed by 12­24 hours of settling, the oil and water will separate, the cleaned oil can be decanted out the valve, leaving the denser soapy water to be drained out the bottom (#5).

This process might have to be repeated two or three times to remove close to 100% of soaps. The second and third washings can be done with water alone. After the third washing any remaining water gets removed by re­heating the oil slowly (Figure 8), the water and other impurities sink to bottom. The finished product should be pH 7, checked with litmus paper or with a digital pH tester.

The water from the third wash can be used for the first or second washes for the next batch. The impurities can be left in the re­heater for the next batch and removed when it accumulates. The soaps can be concentrated, left­over biodiesel can be decanted out and what's left is a biodegradable soap good for many industrial­type uses (degreasers etc.).

I had some success with trapping the concentrated very hydrated sodium from this soap. The way I did this was by pouring the soap onto a stretched cheese cloth and allowing the water to run through leaving the sodium on the cloth. This is as far as I've gone with this so far but it seems one could press much of the water from the sodium then vacuum dessicate this saturated sodium under dry conditions back to a usable sodium hydroxide.

Transesterified and washed biodiesel will become clearer over time as any remaining soaps drop out of the solution.

Figure 7

Figure 8

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Finally Whoa a lot of information in there I know, but even if it sparks your interest to start playing around or even trying biofuel in your vehicle then it has served it’s purpose.

Right then testing your fuel for quality is the biggy. Put your “biodiesel” in a glass jar with some water.(after you’ve drywash, water washed, filtered ,settled or don’t care etc. and shake it for 10 seconds. If it then separates to Biodiesel at the top and water at the bottom you’re on a winner, put it in your tank and go for a drive.

If it turns into mussy white emulsion then you need to work on your washing , filtering whathaveyou.

I’m happy to receive any questions by email and I’ll be publishing a Biodiesel site with forum very shortly so maybe save them for then.

www.GOBIO.co.nz please register on the forum. Now some background on me and my truck.

I’m from England and love NZ with a passion, I work in the computer industry and 4 wheel driving is a hobby along with several other forms of motor sport so I’m no tree hugging environmentalist. Shooting and fishing are also some of my favorite pastimes but I never seem to get round to doing them as often as I would like. (Which no doubt goes for all of us)

I do have kids and believe we are responsible for providing a clean environment for our little ones to grow up in. (a real perk to biodiesel is the reduction in particulates that can cause asthma and chest complaints etc.) Along with making sure we don’t turn over a potential bag of environmental worms to our grandkids.

Fossil fuels are running out and with some lateral thinking NZ could adopt a wider reaching biofuels program with the buy in of the rural industries.

Most of this is down to providing the information to the correct people. That’s you the person reading this right now. We can use biofuel technology to set an example to the world but only if we take the bull by the horns now.

There are interesting developments taking place in the biofuels arena at the moment, technologies like algae co2 filtering for power plants which produce a constant source of algae for production into algal based biodiesel.

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Check out http://www.greenfuelonline.com/emissions_to_biofuels.htm for more info on this. This would be great for the new Helensville Gas power station!

Maybe a biofueled generator with its emissions run­through facility like this with sunlight and you could be close to self sufficient.

Or growing oil palms as listing in http://en.wikipedia.org/wiki/Biodiesel on your own land to supply you with your own biodiesel!

My old landcruiser is a 91 80 series VX ltd 4.2 turbo diesel. It’s an auto and I have run it on unwashed homemade biodiesel for over a year now with no issues.

(Apart from having to drain the tank once as I got my taps mixed up and put glycerin in the tank!!)

The engine is quieter when run on biodiesel and I’ll put a .wav file on the website when it’s ready comparing the 2 fuels (Bio and Dino) on vibration and noise alone.

The extra power is noticeable when driving and comes in handy for those especially sticky mud holes!

Right hope you enjoyed that and I’ll sign off before I start rambling to much.

Feel free to point out any mistakes or errors and I’ll gladly correct them.

Forum and website to follow soon

Biodiesel Break down

B100 = 100% Biodiesel (My mix of preference in my car)

B20 = 20% Biodiesel blend with normal Dinodiesel (the highest mix your likely to see commercially at the pump)

B5 = 5% Biodiesel blend with Dinomuck (This is the “Enforced” biodiesel standard for blend by the government for introduction by 2008 as an alternative and will probably be more expensive too!)

Useful links

http://www.gobionz.com Get it? (Kiwi owned and run for kiwi biodieselers)

http://www.gobio.co.nz

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http://journeytoforever.org/biodiesel.html

http://www.biodieselcommunity.org/gettingstarted/

http://biodiesel.infopop.cc

The National Biodiesel Board's Biodiesel Fuel Fact Sheets (Acrobat files) http://www.biodiesel.org/resources/fuelfactsheets/

The Biodiesel Association of Australia FAQ ­­ see "Biodiesel Fact Sheets" and "Public FAQ" http://www.biodiesel.org.au/

Or just www.google.co.nz Biodiesel home production

Biodiesel facts NZS 7500:2005 NZ Standard

Ow if your still reading the picture in the frames is a small island of the cost of North Wales in the UK called Bardsey or Ynys Enlli (If you be from Wales boyo) it’s pronounced “Ennis enthly” And it’s one of the most serene and beautiful places in the world. And I’d like it to stay that way.

http://www.bardsey.org/english/bardsey/welcome.asp?pid=1

Darren Wood Friday, 5 May 2006

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