jueves, 7 de febrero de 2008

Making Biodiesel

WARNING!!! Making biodiesel involves using dangerous chemicals, creating toxic fumes, and lots of heat. That said, please excercise safety and caution when attempting to make Biodiesel.

*** The Utah Biodiesel Cooperative will not be held liable for any injury, property damage, or other problems resulting from the use of this page. It is for informational purposes only. ***

Basic Production Concept

Biodiesel Production Details

Jack Jones Method - Adopted from Mike Pelly's Method
Written & put together by Graydon Blair of Utah Biodiesel Supply

This method will make approximately 35 to 45 gallons of biodiesel, depending on the quality of the oil used.

1- Pouring Oil Into The Processor
  • Obtain 150 liters (40 gallons) of used vegetable oil
  • Pre-filter the oil by pouring it through a strainer
  • Pour 150 liters (40 gallons) of the oil into the processor
2- Heating the oil prepares it for the reaction
  • Heat the oil to 120 Degrees Farenhiet
  • Check the tempurature with a thermometer

  • A candy or meat thermometer works just fine
  • Recommendation:

  • Don't use an open flame to heat the processor, fumes from the Methoxide used later may ignite--not pretty!
3- Titration is the process used to see how much Lye to add to processor
Items Needed: Distilled Water, Isopropyl Alcohol, Lye (NaOH), Graduated Eye-Dropper, Ph Meter, 2 Small Dishes, 1 Liter container
  1. Create Lye/Water Solution

  2. - Dissolve 50 mL of Lye into 500 mL of Distilled Water in the 1 Liter container
    - You won't use all of this solution for one batch, it's just convenient to have this much on hand
    - When you run out, just make some more
  3. Prepare Dish 1

  4. - Place 5 mL of Lye/Water Solution into Dish 1
    - Place 45 mL of Distilled Water into Dish 1
  5. Prepare Dish 2

  6. - Place 40 mL of Isopropyl Alcohol into Dish 2
    - Place a 4 mL sample of the heated Used Vegitable Oil into Dish 2
    - Mix the contents together, keeping the mixture warm, until the oil is dissolved thoroughly
    - Keeping the mixture warm and mixing will help to keeping the oil from separating
    - Check the Ph of Dish 2 using the Ph Meter
  7. Titrate The Oil

  8. - Drop 1 mL of solution from Dish 1 into Dish 2
    - Measure and record the Ph Level of Dish 2
    - Repeat until the Ph level jumps up 2-3 levels
    - You're looking for a Ph above 8.5
    - As you add drops, the Ph will increase slowly (like from 7 to 7.5)
    - At one point you'll notice a larger jump (like from 7.5 to 9 or 10)
    - When it jumps 2-3 Ph levels, it means the oil has been neutralized
  9. Calculate Titration

  10. L = ((D / 4) + 3.5) * O
    D = Number of 1 mL drops placed in Dish 2 during titration
    O = Milli-liters of oil to be reacted L = Number of grams of Lye needed for reaction to occur
    -Record L for use in next step
4- The Lye/Methonol Mixture - "Methoxide"
Items Needed: Methanol, Lye, and (2) 5 Gallon buckets with lids
  1. Prepare Buckets

  2. - Clean both buckets out
    - Drill 1/4" hole in the center of each lid
  3. Prepare Methanol

  4. - Pour 15 Liters (4 Gallons) of Methonol into each bucket
    - Lightly place the lids on each bucket
    - Take care not to breath the fumes, they're poisonous
  5. Prepare Lye

  6. - Locate the L value from the Titration Step
    - Divide L by 2 to make GL
    - GL = Grams of Lye to use in each bucket
    - Measure out two sets of GL grams of Lye
    - Set aside for use when mixing with the Methanol
  7. Mix The Buckets

  8. - Remove the lid of the first bucket - Using a mixing stick, begin to stir the Methonol in the 1st bucket
    - While the Methanol is still spinning, add the premeasured Lye to the 1st bucket
    - Continue stirring the mixture for about 1 minute
    - Place the lid on loosely and allow to stand for a few minutes
    - Remove the lid and begin stirring again
    - Mix until the Lye is dissolved, approximately 10 minutes
    - Repeat the same process with the second bucket
    - Take care not to breath the fumes, they're still poisonous
5- Pouring "Methoxide" Into Processor
  • Ensure Oil in Processor is at 120 Degrees Farenhiet (or slightly above)
  • Remove the lids from each bucket
  • Carefully pour the contents into the processor
  • Again, take care not to breath the fumes, yep, still poisonous
6- Mixing The Oil causes the chemical reacation to occur
  • Mix 5 Minutes, Wait 10 Minutes
  • Repeat 4 times (Approximately 1 Hour Of Mixing)
7- Allow Oil To Separate
  • Let the mixture sit for at least 8 hours
  • This allows for the Biodiesel and Glycerin to separate
  • The Biodiesel will rise to the top while the Glycerin will fall to the bottom
  • Between the Biodiesel and Glycerin layers may be extra residue, usually soap
  • If this occurs, it means a little too much Lye was used
8- Remove Glycerin Layer
  • Remove the Glycerin (and Soap) layer(s) from the Processor
  • All that should be left in the processor is the unwashed Biodiesel layer
  • Dispose of the Glycerin that was drained off
  • Glycerin can be used as a degreaser, and also can be made into soap
9- Washing The Biodiesel
Washing can be done using a water mister and a bubbler
  1. Misting

  2. - Using a light-mist, add 15 Gallons of water to the processor
    - Allow processor to sit for 10 minutes
    - Drain off water
    - Using a more agressive mist, add another 15 Gallons of water
    - Allow processor to sit for another 10 minutes
    - Do not drain the water, it will be used for the Bubbling
  3. Bubbling

  4. - Place bubbler at bottom of processor and turn on
    - Begin with a light bubble
    - Watch for emulsion to occur, if not occuring, turn up bubbler
    - Bubble Biodiesel for at least 24 hours
    - Turn off the bubbler
10- Allow Water & Oil To Separate
  • Allow Processor to sit for at least 8 hours
  • This allows the water & oil to separate
11- Remove Water Layer
  • Drain off water layer into a container
  • The water should be very clear
  • If the water is not clear, rewash the Biodiesel again
  • If the water is clear, proceed to the next step
12- Transfer To Storage Container The container's should be able to handle Gasoline or Diesel, as Biodiesel has a similar chemical make-up.
  • Drain the remaining Biodiesel layer into an open container
  • Typically, this can be several 5 Gallon Buckets
13- Allow Biodiesel To Dry
This step allows all of the excess moisture to evaporate out of the Biodiesel.
  • Place the open containers in the sun
  • Place screens on top of the open containers
  • Allow the Biodiesel to sit for about 8 hours
  • The length of time will vary by outside tempurature and weather
  • When it's dry, the Biodiesel should not be cloudy
  • You should be able to see the bottom of the container
  • When done, pour the Biodiesel into a storage container
  • Store until ready to use
14- Fill Fuel Tank
  • Fill the fuel tank of any Diesel Engine
  • Biodiesel can be mixed with regular Diesel Fuel in any ratio
  • Once Biodiesel is in tank, you're ready to go

  • - Biodiesel should be treated much like Diesel Fuel
    - Pure Biodiesel can be run in vehicles in tempuratures over 40 degrees Farenheit
    - In cold weather it can be mixed with Diesel Fuel in a 50/50 mixture to keep it from gelling
    - Biodiesel tends to loosen "gunk buildup" in Diesel Fuel Tanks
    - You may need to replace your Fuel Filter after a few tanks
    - Enjoy driving on a completely renewable resource!

Biodiesel Recipes

The method described above is just one of many way's to produce Biodiesel. Below are some links to additional methods for making Biodiesel.

Durco Biodiesel Equipment for Biodiesel Dry Washing & Filtration Systems

/PRZOOM - Newswire/ - The Durco Biodiesel Equipment range of biodiesel dry washing & filtration systems significantly reduces both biodiesel washing time and biodiesel plant start-up & operating costs compared to traditional water / bubble washing techniques.

Buffalo, NY, United States, 07/28/2007 – The Durco Biodiesel Equipment division of Ascension Industries Inc., has announced a new range of Biodiesel Dry Washing & Filtration Systems. The company actually developed these new biodiesel purification & clarification systems from their line of vegetable oil dry washing & filtration units that have been well proven in service since the 1970’s.

Michael DuVal (a Durco Filtration Applications Engineer) explained: “The new range of biodiesel processing equipment uses a 2-Step Magnesium Silicate Dry Wash & Filtration Process to purify and clarify biodiesel into high quality product (capable of meeting or exceeding ASTM-D6571 requirements) from a wide range of biodiesel from prepared feedstocks of; yellow grease, tallow, canola oil, palm oil, rapeseed oil, soybean oil, waste vegetable oil (wvo), etc. Durco pilot plant filtration units are now openly available for performance trials at any particular biodiesel plant, in order to optimize a given producers process and verify the resulting biodiesel product specifications.

Unlike traditional water washing or bubble washing equipment, these new dry washing systems achieve highly efficient removal of contaminants found in preparations of methyl-ester (biodiesel). The systems utilize the “surface activity” and high surface area of magnesium silicate adsorbent powder to refine biodiesel containing residual glycerol, and other impurity components. The Filtration Step then removes the contaminated adsorbent and all other particulate down into the sub-micron particulate size range. The purified and clarified biodiesel product may then be sent for sale or storage, and the filtered particulate by-product may be utilized for fertilizer, animal feed, or various other environmentally friendly applications.”

The filtration step may use one of two proven filtration technologies:

- Biodiesel Filter Press Technology (<10mgal/yr,>

- Biodiesel Pressure Leaf Filter Technology (typically >10M gal/yr or much higher, with essentially unlimited high temperature capability for enhanced biodiesel washing).

A wide range of suspended solids (typically 0.5-2% by weight) may be removed, with the optimum choice of filter technology depending on the size of the biodiesel production operation, and several other process factors. Fully automated operation and an optional fail-safe filter station are also offered. Extended solids capture is additionally possible, using downstream Tubular Filter Technology. Durco Biodiesel Dry Washing & Filtration Systems reduce overall biodiesel production time and cost because they eliminate the need for an oil/water emulsion gravity settling stage or a drying stage. This also significantly reduces biodiesel plant start-up and operating costs by eliminating the capital and maintenance associated with the traditional washing equipment.

Another major benefit of these highly efficient biodiesel processing systems is that they do not produce water effluent waste streams, which are hazardous by-products of traditional biodiesel washing & drying techniques.

Durco Biodiesel Dry Washing And Filtration Systems are offered as complete turnkey packages, although individual filter units are also available. These operator-friendly systems can be rated for both ‘non-explosion proof’ or ‘explosion-proof’ areas, and may be configured for either continuous or batch processes.

viernes, 30 de noviembre de 2007

Quality Assurance of Biodiesel by Water Content Determination

Quality problems caused by water in biofuel

While the negative effects of particle contamination in fuels is well-known, the effects of water contamination were widely underestimated. Depending on the water content, water exists as dissolved water, dispersed throughout the oil, as emulsified microscopic droplets or as a separate phase of free water. Besides the reduction of the calorific value of the bulk fuel resulting in slower acceleration, less power and harder starting, the contamination with water enhances rust formation and corrosion of vital fuel system components. At temperatures below 0 °C the forming of ice crystalls can clog fuel lines and enhances crystallisation processes within the biodiesel.

The presence of water not only reverses the FAME to fatty acids, but it significantly promotes the growth of bacteria and fungi oxidizing the biodiesel to corrosive degradation products (organic acids). Additionally, water hydrolyses certain stabilisers, such as phenolic antioxidans, thus overruling their interceptive character. Resulting oxidation products can cause disturbances in the injection system and in the engine itself. In view of this, the EN 14214 standard specifies a maximum water content of 500 ppm for biodiesel.

Introducing The Biodiesel & Feedstock Water Test Kit

Now you can use the same kit commercial Biodiesel producers use to measure the percent of water in any liquid sample with extreme accuracy. This industrial quality tester allows you to quickly and accurately identify just how much water content is in a sample of any oil feedstock or finished biodiesel sample.

How It Works
The test works by placing a sample of fluid into the testing unit and then adding a reacting agent. The tester is then sealed and within a few minutes the test is ready to read. The tester works by causing a chemical reaction to occur between the water in the test sample and the reagent. The reagent converts the water to hydrogen gas which gives off pressure. The amount of pressure given off directly correlates to the percentage of water in the sample.

Testing Range
This great tester can read anywhere from .005% (50 PPM) to over 50% (500,000 PPM) using the techniques found in the manual. There's a series of 5 different ranges that can be used to measure across so the test is extremely versatile. Test results can be read in as little as 5 minutes and are extremely accurate.

Portable, Small, & Easy To Use
Because the test kit is comprised of just the tester, some reagent, and dry solvent, it can be used out in the field or in any test lab and because the results are so accurate you can be sure you're adjusting your Biodiesel production recipes accurately.

Why Test For Water Content?
Water is problematic in the biodiesel production process for many reasons. If it's present in the starting feedstock it can hinder a successful reaction thereby causing unreacted fuel to be produced. By knowing what the water percentage is prior to making biodiesel, certain counter measures can be used to either eliminate the water from the feedstock or compensate for it being there.

Within the ASTM Specification for biodiesel (ASTM D-6751), there's also a requirement for a maximum water percentage in the finished biodiesel. If the percent of water is over this limit the biodiesel won't meet the ASTM specification and shouldn't be introduced into the market place.

By conducting a simple water test on the feedstock, you'll know where you're starting and what steps may be necessary to deal with any water content. Then, after you've produced the biodiesel, you can check the finished biodiesel for water content again to ensure it meets the ASTM guideline. If it doesn't, appropriate "drying" measures can be used to bring the biodiesel into specification.

The deluxe kit comes with everything you'll need to perform 50 quick water tests.

More information

How to Use Biodiesel

Biodiesel can be mixed with petroleum diesel in any proportion. To prevent gelling in cold weather, blend your biodiesel with Number 1 petroleum diesel. Biodiesel can be mixed with heating fuel and used in oil-fired heating equipment, and it can be used in some lamps designed to burn kerosene. Your biodiesel's cold weather performance depends upon what you use for oil. Canola or rapeseed oil-based biodiesel will have better cold weather flow characteristics than biodiesel made from coconut oil or animal fat.

Washing Biodiesel

Unwashed biodiesel will not meet ASTM (American Society of Testing and Materials) standards. For more information about ASTM standards, and testing and specifications for biodiesel and other diesel fuels, see Resources. Remember, equipment and engine manufacturers only warranty their equipment and engines for their material and manufacturer defects. Fuel manufacturers (in this case, you) assume responsibility for any damage caused by the fuel. Washing biodiesel is easy to do, and requires only water and time.

Why wash biodiesel?

The biodiesel produced with the process described above will work in some heating and lighting equipment and may be used to fuel diesel engines. Most impurities settle out into the glycerol layer—including unfiltered particulates, methanol, and glycerin. Some sources encourage using unwashed biodiesel, because washing biodiesel is a time-consuming process. However, some alcohol, sodium hydroxide, and soap remain suspended throughout the biodiesel after the transesterification is complete. Water in biodiesel can lead to biological growth as the fuel degrades. Unreacted methanol in the biodiesel fuel can result in fire or explosion and can corrode engine components. The catalyst, sodium hydroxide, can also attack other engine components. Since the methanol and sodium hydroxide are chemical bases, unwashed biodiesel is caustic and may damage diesel engine components. Soap is not a fuel and will reduce fuel lubricity and cause injector coking and other deposits. At the 5-gallon batch quantity described above, it is not feasible to reclaim the methanol. If you begin making significant quantities of biodiesel, you should reclaim the unreacted methanol, because the reclaimed methanol represents a significant cost savings, and methanol is a pollutant in its own right.

Minimize contamination

To minimize impurities in the biodiesel, filter the oil before you mix it with methoxide. Remove all the water from waste vegetable oil by heating it before it is processed into biodiesel. Do not use any more methanol or sodium hydroxide than is needed to have an efficient reaction.

Most of the unreacted sodium hydroxide ends up in the glycerol layer and can be discarded or used to make soap (see Soap Making Using Biodiesel Waste). Most soap (if there is any water and FFA in the oil you started with) ends up in a white layer between the glycerol and the biodiesel. Drain this layer off with the glycerol before washing the biodiesel.

Remove unreacted methanol

Unreacted alcohol may be distilled from the biodiesel and reclaimed for use in future batches (more than one quarter of the methanol in the recipe will end up unreacted). Although alcohol reclamation is beyond the scope of this publication, note that methanol boils at 148°F at sea level. Methanol can be driven from biodiesel by heating it; do this outside or vent the methanol to the outside. Never breathe methanol fumes. A much better and safer solution is to use a vacuum pump to lower the pressure of a closed tank. The methanol can be collected and re-used. See the Resources section on methanol reclamation.

Washing Techniques

There are three techniques for washing biodiesel: agitation washing, mist washing, and bubble washing. The process of washing biodiesel involves mixing it with water. Water is heavier than biodiesel and absorbs the excess alcohol, sodium hydroxide, and soap suspended in it. After washing and settling, the water and the impurities in the water can be drained from the bottom of the container. Several wash cycles are generally needed. The first water drained off the bottom of the biodiesel will be milky, and the final wash water drained off will be clear. Excess sodium hydroxide in the biodiesel will form soap when mixed with water, and it takes a while for the soap to settle out. Depending on the method you use, it takes roughly as much water as biodiesel for a wash cycle. Initial washings must involve gentle mixing to minimize the formation of soap that will take time to settle out. However, you want the mixing to be thorough and for the water to be dispersed throughout the biodiesel. Agitation washing amounts to stirring water into the biodiesel, letting it settle, and draining it off. Mist washing is spraying a fine mist of water over the surface of the biodiesel. Tiny droplets of water fall through the biodiesel and pick up impurities on the way down. Bubble washing is done by putting a bubbler in a layer of water beneath the biodiesel in a container. As the bubbles rise they are coated with water, which picks up impurities as it travels up and then back down through the biodiesel.

Washing a Small Batch (courtesy of "Squire Tilly")

This is a simple, nearly foolproof method for washing small test batches of biodiesel, and I have often washed a sample of biodiesel in less than an hour using this method.

Be aware that unwashed biodiesel contains soap. If you agitate your first few washes too vigorously, the water, soap, and biodiesel will likely form an emulsion that may take days or weeks to separate.

Prior to washing, let the unwashed biodiesel settle for at least eight hours and possibly as long as a week to get rid of as much excess sodium hydroxide as possible.

In addition to unwashed biodiesel, you will need water, and a container about twice the volume of the biodiesel you are washing (you may use the container in which you reacted the biodiesel, but this ties up that container, so you will probably want to use another container).

The three important things to remember in washing are GENTLY GENTLY GENTLY.

Washing Technique

Pour 1 liter of biodiesel into a 2-liter plastic soft drink bottle. Gently pour about 500 milliliters of lukewarm water into the bottle. Seal with a cap that will not leak. GENTLY rotate bottle end for end for about 30 seconds. After 30 seconds place the bottle upright.

If you have been GENTLE, the water and biodiesel will separate immediately.

You will notice the water is not clear.

Wearing rubber gloves, remove the cap, and using your thumb as a valve, turn the bottle upside down and drain the water. Drain the water into a bucket and allow it to evaporate. Discard any residue.

Repeat the process of adding 500 milliliters of lukewarm water, gently shaking, and draining off the water four or five times. Each time that you repeat the process, you should shake the mixture a little more vigorously and for a little longer, until by the fifth washing you are shaking the mixture very strongly for about a minute or a little more.

Washed biodiesel is VERY CLOUDY, much lighter in color than the original biodiesel, and looks terrible. After a day or two of settling and drying it will clear.

Washing a Larger Batch
Agitation Washing
Gently mix equal parts water and unwashed biodiesel and let settle until clear. Repeat several times, until the water is clear. Pump the biodiesel off of the top of the water (or drain the water off the bottom), dry the biodiesel for a few days in the sun.
Bubble Washing

An air pump, hose, and air stone can be bought from an aquarium supply store. Put the weighted air stone in the bottom of your bucket along with the biodiesel. Then gently add about 1/3 as much water as you have biodiesel to wash. Start the air pump and allow the bubbles to gently wash the biodiesel for several hours. Drain off the milky water, and repeat this process, letting the air pump run longer during each washing cycle, until the water remains clear. If the bubbles cause foam to form, use less air. You want to start out GENTLY. After the last water drained is clear, dry the biodiesel (see below) and it is ready to be used as diesel engine fuel.

Mist Washing

Purchase a misting nozzle from a pet store (these are used to keep reptiles cool) or from a drip irrigation company and connect it to your domestic water faucet. Turn the water on to make a fine, gentle mist, and allow the mist to float over the surface of the biodiesel. Keep the misting nozzle above the biodiesel. Mist the biodiesel until you have several gallons of milky water in the bottom of the container, then drain it off. Repeat this process several times, until the water you drain off is clear. Dry the biodiesel until it is clear, and you can use it for diesel fuel.

Drying washed biodiesel

After the biodiesel is washed, it should be dried until it is clear. This can be done by letting the biodiesel sit (covered) in a sunny location for a few days, or it may be heated to about 120°F for a few hours. Reacted, washed, and dried biodiesel may be used in any diesel engine. It should have a pH of close to 7, or chemically neutral, and it should have no methanol left in it.

Making a Larger Batch Using Used Fryer Oil

Used fryer oil is a little different from new oil. Used oil probably has water and food particles in it. Used oil also contains free fatty acids caused by cooking with it. Remember that the titration will give you the number of additional grams of sodium hydroxide per liter of waste oil, so you must multiply the number of additional grams of sodium hydroxide by the number of liters of waste oil you are using.

Use the same equipment as you did making a 5-gallon batch with new oil. There is a handy chart in From the Fryer to the Fuel Tank (see How-To Resources) for the amount of sodium hydroxide to use for various quantities of oil and various titration numbers.


Perform a titration on the waste oil, to determine how much sodium hydroxide is needed for the reaction (in addition to the 3.5 grams per liter of new oil). Have all the materials warm, room temperature at the coolest, 130°F at the warmest. To filter waste vegetable oil, warm it in a stockpot, and pour it through a filter paper. These and the filter basket are available from restaurant supply stores. If the oil is very warm, let it cool to 120°F. Filter the oil and remove water as described above.

Follow the directions above for making a 5-gallon batch using new oil, but using the amount of sodium hydroxide called for by the titration.