Building a Biodiesel Processor March 24 2006 Hosted

Building a Biodiesel Processor March 24, 2006 Hosted by: Paul Feather and The Collaborative Biodiesel Project

Outline Biodiesel and Vegetable Oil Basics n How Biodiesel is Made n Safety n Small Scale Processor Design n Economics n

Basics

What Is Biodiesel? n n n Biodiesel is a diesel fuel made from vegetable oil, methanol and a catalyst. Biodiesel is the only alternative fuel that has passed all of the EPA clean air fuel requirements. Biodiesel is fully compatible with any diesel engine. It has been tested more thoroughly than any other alternative fuel. Biodiesel is safe to handle and is biodegradable, it is less toxic than table salt. Best of all, Biodiesel can be made quite easily using recycled waste vegetable oil.

Biodiesel Blends n Biodiesel is fully compatible with petroleum diesel, it can therefore be blended with diesel to: n n n decrease cost increase performance improve cold weather characteristics The state of Minnesota currently sells all diesel as a blend of B 2 Most common biodiesel blend is B 20

Cold Weather and Biodiesel n Everything is harder n n n Oil quality is more important Collection is more difficult Settling is more difficult Pumping and filtration is more difficult Fuel gelling is a problem below 32°F Your design must be tolerant of winter conditions

Emissions Reductions of Biodiesel Compared to Diesel

Other Uses for Biodiesel makes a great degreaser n Biodiesel as Home Heating Oil n n Emmisions are further reduced with open-flame combustion n NOx emmisions eliminated compared to fuel oil

What is SVO? n n n A Straight Vegetable Oil system requires a secondary, heated fuel tank. A valve is installed so that Diesel or SVO can be burned. Any oil can be used, but it must be filtered and water free.

Basics of an SVO System n Two-Tank System Heated vegetable oil tank n n n Fuel Switching Valve Allows you to start on Diesel(or Biodiesel) switch to vegetable oil while driving, then switch back to Diesel(or Biodiesel) for purge/shut -down. Second Fuel Filter n n Usually heated using engine’s heat - via coolant Can be heated with electric elements Inline electric, or coolant fuel heaters, and heated filters are available. Filters down to at least 10 microns Systems generally cost $500 -1500 (see www. frybrid. com or www. biofuels. ca)

Biodiesel Vs. SVO is (generally) free, but initial system cost is high n Biodiesel is Pour and Go, SVO requires more user maintenance n SVO emmisions are higher in idle and traffic conditions n Biodiesel’s solvency will degrade rubber fuel lines, SVO will not n

How Biodiesel Is Made Chemistry n Recipe n Titrations n

Basic Recipe 1. 2. 3. 4. 5. Collect, process, and heat oil. Measure 1 part methanol to 5 parts oil. Measure lye and mix methoxide. Mix oil and methoxide together for one hour. Settle, and drain glycerin.

Chemistry The chemical structure of oil. n Transesterification – the biodiesel reaction. n CH 2 OORa catalyst CH 2 OH | | CHOORb + 3 CH 3 OH 3 CH 3 OORx + CHOH | | CH 2 OORc CH 2 OH Oil Methanol Biodiesel Glycerin

Titration When oil is fried too hot too long, the fatty acids break off, acidifying the oil. n Titration is necessary to determine the acidity of oil. n Use a stock solution of known strength, and phenolphthalein indicator. n Creates a 1/1000 scale reaction. n

How much lye? Use 4 g Na. OH per liter plus titration. n Or use 6 g KOH per liter plus titration. n KOH is more expensive n Na. OH doesn’t dissolve as well, and the glycerin tends to solidify at higher temperatures? n

Safety

Safety n Potential hazards include, and are not limited to: n n n Fire Chemical exposure Spills Explosion Recommended personal protection measures n n Gloves Goggles Ventilation Acid for neutralization

Additional safety equipment to consider Fire extinguishers n Secondary Containment n Sealed vessels n Respirators n Explosion proof motors n Pumps rated for volatile materials n Grounding n

Processor Design

Processor Design n n Oil Collection WVO Settling Tanks Heating System Filters Methoxide Mixing n n Processor Settling Wash/Dry Settling/Final Storage

Oil Collection Relationship with restaurants n DC pump, or portable inverter n Hand Dipping n Hand pumps n Legality issues n

Oil quality n De-watering n Heat, gravity and time Filtration n Hydrogenated oils n Rancid oil n Oil quality = fuel quality n

Heating n You must have a way to heat oil n n Ideal reaction temperature is 120°F Ideal settling temperatures are above 80°F Heated space is sufficient for settling, but not reaction. The heating system is a vital component of the processor design.

Solar Thermal Heating

Heating Options n Electric elements n n n Passive solar (greenhouses, black tanks, etc. ) n n Free. No emissions. Great for pre-heating. Active solar n n Relatively cheap (ballpark 2¢/gallon). Easy to control Exports emissions elsewhere Can be an expensive installation. Great investment. Gas, wood, biodiesel, oil, and other fuels. n Processor should be indirectly heated. Price varies with fuel.

Filtration n Filter oil n n Only practical if oil is hot, or if the filter can slowly drain. Large surface area. (sock filters, etc. ) Provides higher quality glycerine. Filter biodiesel n n 10 microns at least. Water separator removes glycerine.

Methoxide Mixing Most dangerous activity in the process. n Hand pumps are safe for small scale. n KOH dissolves easily. n n Spraying methanol over KOH is sufficient. Na. OH should be mixed or re-circulated. Sealed tank.

Processor Designed to mix methoxide and oil. Optionally designed to separate glycerin. n Sealed. Probably heated. n Propellers are great, but tricky to install in a sealed tank. n Pump mixing is effective in small scale, especially when combined with a mixing tube. n

Settling is valuable at every stage in the process. n Allows you to drain glycerin, water, particles, oil, etc. n Every tank should drain from the bottom, and conical tanks are very helpful. n Settling will not occur below ~45°F n

Washing New fuel contains unreacted or partially reacted material, glycerin, soaps, water, and methanol. n Settling removes most of this material. n For completely clean fuel, you have to wash it. n n n Mist and/or bubble water through the fuel. Use magnesium silicate. (Magnesol).

Water washing n n Most impurities would rather dissolve in water than biodiesel. Water is heavy, and settles out, carrying impurities with it. Pros Well tested Cons Time Consuming Water is cheap Fuel must be dried Wastewater

Magnesol washing n Magnesium Silicate absorbs impurities, and is then filtered out. Pros Cons Fast Some particles are extremely small. (1 micron) Somewhat expensive. Ballpark 6¢/gallon. Can’t make it yourself. No wastewater

Drying after a water wash. Heat, time and gravity. n Air flow helps with drying. Warm air can absorb more water than cold air. n Well washed fuel dries easily. n

Quality Control and Testing n n Visual inspection for clarity. Specific gravity = 0. 86 Emulsion tests Cloud and gel point measurements. n n n Cloud point should be 25 -32°F Gel point should be about 15°F Water content should be very low. (weigh, boil and weigh again). Total and free glycerin measurements with spectrophotometry Gas chromatography

Byproducts n Methanol recovery is safe, responsible, and economical n n n Glycerin n n Can be distilled. Methanol boils at 148°F (lower in a vaccuum) Distillation in the processor is convenient. Contains methanol if you don’t recover it. Good for soap, compost, and many other things. Wash water Low quality fuel and oil

Glycerin Soap Terra is boiling the methanol off of some glycerin so that it can be made into soap

Materials Compatibility Good n n n Aluminum Stainless Steel Flourinated plastics Teflon, viton, nylon Fiberglass Bad n n n Zinc Copper, brass, bronze Nitrile rubber Polypropylene Polyvinyl Tygon Biodiesel Handling and Use Guidelines, NREL, 2004.

Processors

Economics – consumables. Oil is still free. n Methanol is the most expensive ingredient (about $150 for a 55 gallon drum). That represents 55¢ per gallon of biodiesel. n KOH costs around $1/lb, representing 6¢ per gallon of biodiesel. Alternatively, Na. OH adds about 3¢ per gallon. n Fuel for heating depends on your situation. n

Economics n Labor. n n n Labor times are short, but spread out. Oil collection can be labor intensive, and requires fuel. Space. n Need an indoor space in winter. Building codes and restrictions can be a problem.

Economics n Capital n Tanks n n n Pumps n n Can be recycled water heaters, fuel oil tanks, etc. Can be off-the-shelf plastic or stainless. Can spend $35 to $700 on a pump. Plumbing n Fittings add up quick.

Great Biodiesel Websites www. biodieselcommunity. org – Great Grassroots, Beginners Website biodiesel. infopop. cc- THE discussion board for all things Biodiesel www. biodiesel. org – The Industry Webpage, news, pump locations, etc. www. biodiesel. appstate. edu – ASU Biodiesel Project, soon to be a bastion of quality info on small scale biodiesel design www. utahbiodieselsupply. com – Great source for homebrew supplies www. pumpbiz. com – Great source for high quality pumps www. me. iastate. edu/biodiesel - Technical info on Biodiesel www. biofuels. coop – Piedmont Biofuels website, Home to the worldfamous ‘Energy Blog’

The Collaborative Biodiesel Project Contact Dr. Jeff Ramsdell ramsdellje@appstate. edu Paul Feather pf 65033@appstate. edu Jeremy Ferrell jcferrell@care 2. com