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BioFuels: Understanding their BioFuels: Understanding their Potential and LimitationsPotential and Limitations

Jim GlanceyDepartments of Bioresources Engineering

and Mechanical Engineering

University of DelawareNewark, DE 19716

Discussion Items

The Basics of BiodieselProduction, Distribution and BlendingPerformance as an Engine FuelWarrantiesHeating Oil Handling and Storage to Maintain Fuel Quality

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Biodiesel – Driving Forces

Excess supply of fats and oilsPotential for better emissionReduce dependence on petroleumIncrease lubricity of the fuel to compensate for lower Sulfur contentSafety and handling – less volatile fuelIncentive Programs

What is Biodiesel?

A compression ignited fuel made from a renewable resourceChemically

Long chain fatty acid mono alkyl estersExact chemical composition different for different sources of oil.Combustion

Biodiesel Air/Fuel Ratio = 13.5Petro-Diesel Air/Fuel Ratio = 15

Its a good solvent

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Catalysis = potassium or sodium hydroxide

Biodiesel Sources

Vegetable OilSoyCanola/RapeseedCornCottonUsed cooking by-products

AnimalBeef tallowPork lardUsed cooking by-products

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Important Processing Considerations

Complete reaction = no un-reacted oilRemoval of GlycerinRemoval of CatalystRemoval of AlcoholAbsence of free fatty acids

Insured through ASTM D6751

Classifications

Biodiesel always refers to 100% biofuel.Biodiesel Blends refers to a fuel that is composed of a mix of Biodiesel and Petroleum-Based DieselBlend Designations

BXX – XX is the % Biodiesel

Examples:B20 – 20% Biodiesel, 80% Petro-DieselB100 – 100% Biodiesel (Neat)

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Worldwide Fuel Charter

-ASTM 6751-B5 Recommendation

Blending

Biodiesel that meets ASTM 6751 is blended with Petroleum Diesel Fuel.

Some common blends: B2, B5, B20

Biodiesel is heavier than Petroleum DieselSplash Blending (Tank Mixing)

Always add biodiesel on top of petroleum dieselCheap and effective for mixing

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Rack or In-Line Blending

Simple Rack BlenderBlending with Additives

Blending in Delaware/Maryland

Distributors with up to 3 years experienceBuying B100 from Iowa and OhioBlend B100 with petro-diesel.Underground Tanks for B100 are temperature controlledSell everything from B2 to B100Cold flow improver in bulk B100

-40 F pour point in B2030 F in B100

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Biodiesel Blend Quality

Unlike gas engines, diesel engines will run on poor fuel.

Currently, no good test or standard exists for blended biodiesel.

Once blended, it is difficult to determine if good quality biodiesel was used.

So . . . you need to interrogate and rely on your supplier to confirm quality.

Biodiesel Performance

Power and EfficiencyEmissionsLow TemperatureMaterial CompatibilityCost

Taken at the diesel truck drag races on Rt. 13 just outside Greenwood, DE

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Performance – Energy Value

Power and Efficiency Compared to Petroleum Diesel

B100 – 10% less energy per gallonB20 – about 2% less energy per gallonRoad studies of fuel efficiency reductions

B100: 4.1 to 10.1 MPGB20: 0.9 to 2.1 MPG

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Emissions from Biodiesel Blends Compared to Petroleum Diesel

Emissions . . .

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Cloud Point for a Biodiesel and Biodiesel Blends – no additives

B100 25 to 30 FB20• Soybean-base -14 F• Canola/Rapeseed-base -15 F• Lard-base -3 F• Eatable Tallow -2 F• Fatty Acid Grease -6 F

Cloud Point - Temperature at which wax crystals startto form.

Cold Filter Plug Point

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Material Compatibility

Soft MetalCopper, brass, zinc, lead and tin parts should be replaced with aluminum or steel since these metals oxidize both diesel and Biodiesel fuels.

SealsTeflon and Viton are must use sealing devices, not Buna, Nitrile, Polyurethane. Polypropylene and Polyvinyl are not acceptable sealing devices.

Biodiesel Costs

B100 – about $3.00/gal at the pump$2.00/gal for the fuel$0.50/gal rail charge from Iowa$0.50/gal road tax

B20 - $1.76/gal at the pumpRule of thumb – an extra penny per gallon for each percentage point of biodiesel

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Warranty Issues

Cummins and Caterpillar“neither approves or disproves the use of biodiesel fuel and blends”Problems causes by the fuel will not be covered.

CaterpillarB5 blend maximum for 3003 through 3034, 3054, 3056 engine modelsOther models - blended at any percentages are OK.

Warranty Issues . . .

John DeereMost recent policy statement regarding Biodiesel blends was February, 2002.Approved up to 5% soy-based blend in all Power Tech engines.“We do not endorse using higher percentage blends at this time”Why?

Possible fuel quality issuesDeere R&D is consumed with developing a new engine to meet the Tier 3 emission requirements required in 2006.

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Warranty Issues . . .

VolkswagenSome claims that VW voids warranties if biodiesel blends are used.Currently, European VW engines are warranted for B20 and B100. VW had invested in “Sunfuel” - biodiesel from biomass. Volkswagen AG and Archer Daniels Midland Announce Biodiesel Research AgreementAnnounced Monday January 5

Biodiesel Blends as Heating Fuel

B2 and B5 have been usedEmissions including NOx goes downGiven the change in fuel chemistry, adjustment of the air/fuel ratio may be required.Soft metal fuel lines (copper) and natural rubber present problems

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Maintaining Fuel Quality

Purchase only quality fuel and keep it cleanStart with clean storageMinimize Contaminants

AirWaterFuelMicrobes

Don’t store biodiesel for more than 6 monthsRegular housekeepingProblems usually occur early

Fuel Additives

Four Types for DieselEngine PerformanceFuel StabilityFuel HandlingContamination Control

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Biodiesel Incentive Programs

Delaware Soybean BoardPaying for a soybean grower’s first purchase of BiodieselPlanning to offer totes

MD Soybean BoardRefunds half the cost up to $1000Giving away $275 totes

SummaryExtensive research exists on biodiesel formulations and performance.

One of the biggest challenges for the industry is insuring consistent quality at a competitive price.

Important issues for end users:Know and trust your source of fuelMake sure fuel meets fuel standardsWhen in doubt, verify warranty policyCheck regularly for seal degradation with older engines

End users responsible for maintaining fuel quality.