Biodiesel Technical Training Course

BIO3.2:Biodiesel Fuel Quality

Presented by the National Biodiesel

Board

ASTMAmerican Society of Testing & Materials

Biodiesel Specifications and Fuel Quality

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• Provide instruction on diesel fuel properties• Provide instruction on biodiesel fuel properties• Provide instruction on how these properties affect fuel

quality and fuel filtration• Provide information on the BQ-9000 program• Provide access to industry experts for more detailed

questions and answers about biodiesel• Introduce the National Biodiesel Board’s Diesel Technician

Training program and the program resources to the audience

Learning Objectives

• Be able to identify key ASTM diesel fuel quality parameters• Be able to identify key ASTM biodiesel fuel quality

parameters • Be able to describe how these properties affect fuel quality

and fuel filtration• Be able to explain the importance of biodiesel fuel quality

and the BQ-9000 program • Be able to discern issues between normal diesel problems

and poor quality biodiesel imposters or out-of-spec biodiesel when they hit the shop

Learning Outcomes

Biodiesel Defined

• Biodiesel, n. -- a fuel comprised of mono-alkyl esters of long chain fatty acids derived from vegetable oils or animal fats, meeting ASTM D 6751, designated B100.

• Biodiesel Blend, n. -- a blend of biodiesel fuel with petroleum-based diesel fuel designated BXX, where XX is the volume percent of biodiesel.• This tight definition was needed in order to secure vehicle,

engine and fuel injection equipment company support for biodiesel, as well as to secure ASTM specs

Biodiesel (B100) Attributes

• High Cetane (avg. over 50)• Ultra Low Sulfur (avg. ~ 2 ppm)• High Lubricity, even in blends as low as 1-2%• High Energy Balance (4.5 to 1)• Renewable, Sustainable, Domestically Produced• Increases overall fuel production capacity in

USA • Reduces HC, PM, CO in existing diesel engines

ASTM Standards for Biodiesel• ASTM D6751 is the approved standard for B100 for

blending up to B20, in effect since 2001– Performance-based standard: Feedstock and Process Neutral– 47 states have now legislatively adopted the ASTM D6751

specifications for biodiesel

• D975 – Covers petrodiesel and blends up to 5% biodiesel maximum for on/off road engines

• D7467 – Covers blends containing 6% to 20% biodiesel for on/off road engines

• 47 States have adopted ASTM D6751 into law

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Biodiesel Specifications

BQ-9000 Program

•Biodiesel Industry’s equivalent to an ISO 9000 program for biodiesel production & distribution companies as well as testing labs

•BQ-9000 works hand-in-hand with the ASTM specifications for biodiesel

•Quality Control System covers biodiesel manufacturing, sampling, testing, blending, storage, shipping, distribution

•ASTM Grade Fuel, BQ-9000 Companies•Many OEMs are now either requiring or strongly encouraging BQ-9000 8

Quality, Quality, Quality

• B100 must meet D 6751 prior to blending to insure trouble-free use of B20 and lower blends

• BQ-9000 fuel quality program helps to promote high quality fuel from producers and marketers

• B20 and lower blends are recommended since most of the research and successful use of the fuel has been with these blends– See NBB Toolkit document “Use of Biodiesel Blends Up to B20” for more

information

• Blends over B20 require special precautions and should only be used by knowledgeable and experienced users– See NBB document “Guidance on Biodiesel Blends Above B20” for more

information: http://www.biodiesel.org/pdf_files/fuelfactsheets/Use_of_Biodiesel_Blends_above_%2020.pdf

• Off specification biodiesel can cause engine operability problems

• Quality is critical to continue to grow the industry– There is NO room for off-specification fuel– Customers need to receive consistent quality from lot to lot, batch

to batch– Must be on-spec for tax credit and to be legal fuel

Why care about biodiesel quality?

• Biodiesel production review• Key elements in ASTM Specifications and Standard Test Methods• ASTM Specification D 6751 – 11, the specification of B100 (biodiesel) fuel is described in detail.• Key properties of B 100 are discussed in terms of their tests and

specifications.• Alternative testing procedures• Other issues affecting fuel quality

Summary

• Biodiesel is produced by a chemical reaction between methanol (or ethanol) and an oil or fat, in the presence of a catalyst.

• Requires a strong basic catalyst (NaOH or KOH)• The reaction is called “Transesterification”

– Changing one ester (vegetable oil) into another ester (biodiesel)

• Oil + Alcohol yields Biodiesel + Glycerol

Review of the Production Process

Transesterification (the biodiesel reaction)

Fatty Acid Chain

Glycerol

Methanol (or Ethanol)

One triglyceride molecule is converted into three mono alkyl ester (biodiesel) molecules

Biodiesel

Triglyceride

• Methanol – Degrades some plastics and elastomers, corrosive; Can lower flashpoint to unsafe levels (fire safety)

• Unconverted/partly converted oils (bound glycerin) – Results in very poor cold flow properties, injector and in-cylinder deposits, potential engine failure

• Free Glycerin – Results in injector deposits, clogged fuel filters, deposit at bottom of fuel storage tank

• Catalyst (caustic, NaOH) – Excessive injector, fuel pump, piston, and ring wear, filter plugging, issues with lubricant

• All are limited by ASTM D6751 specification

Potential Impurities: in Biodiesel

ASTM Standards for Biodiesel

• ASTM D6751 is the approved standard for B100 for blending up to B20, since 2001– Performance-based standard: Feedstock and Process Neutral

• D975 – Add up to 5% biodiesel in Petrodiesel • D396 – Add up to 5% biodiesel in Heating Oil• D7467 – New standard for on/off road blends of B6 to B20

• Major steps forward for passage of biodiesel blend specifications

• Critical for obtaining OEM approval

• Critical for ensuring that biodiesel performs as advertised so market can grow

Property Test Method Limits Units

Calcium & Magnesium EN 14538 5 max ppm(ug/g)Alcohol control

either Flash Point D 93 130 min. Degrees C or GC methanol EN 14110 0.2 % Volume

Flash Point D 93 93min. Degrees CKin. Viscosity, 40C D 445 1.9 - 6.0 mm?/sec.Sulfated Ash D 874 0.02 max. % massSulfur S500 D 5453 0.05 max (500) % mass (ppm)

S15 D 5453 0.0015 max (15) % mass (ppm)Copper Corrosion D 130 No. 3 max.Cetane number D 613 47 min.Cloud Point D 2500 Report degrees CCarbon Residue D 4530 0.05 max. % massAcid Number D 664 0.50 max. mg KOH/gFree Glycerin D 6854 0.020 % massTotal Glycerin D 6854 0.240 % massPhosphorous content D 4951 0.001 max % massDistillation, T90 AET D 1160 360 max degrees CNa/K, combined EN 14538 5 max ppm(ug/g)Oxidation Stability EN 14112 3 min hours

(Visual Appearance)D 4176 Free of un-dissolved water, sediment and suspended matter

BOLD = BQ-9000 Critical Specification TestingOnce Production Process Under Control

B100 Blending Component Specification

QuickTime™ and aTIFF (Uncompressed) decompressor

are needed to see this picture.

ASTM D7467: B6-B20 Blend Specification

Impact of Blended Specs

• More large fleets are using B20• Nearly 55% of OEMs in the U.S. now support B20 or higher

blends in at least some of their equipment• Biodiesel blends are the only non-petroleum diesel

substitute to have officially sanctioned ASTM specifications• Quality is further improved, fuel specs can be enforced by

regulatory bodies (supported by NBB)• Biodiesel companies have made process changes in order to

meet D6751

Biodiesel Pump Labeling

No Label Required: Fuel blends containing no more than five percent biodiesel

and no more than 5 percent biomass-based diesel and that meet ASTM D975.

Labels Required: Fuel blends containing more than five but no more than 20

percent biodiesel or biomass-based diesel. Fuel blends containing more than 20 percent biodiesel or

biomass-based diesel.

Separate Labels for Biodiesel (Blue Labels) and Biomass-Based Diesel (Orange Labels)

BQ-9000 Fuel Quality Program

BQ-9000 ProgramBiodiesel Industry’s equivalent to an ISO 9000 program for biodiesel production & distribution companies as well as testing labs

BQ-9000 works hand-in-hand with the ASTM specifications for biodiesel

Quality Control System covers biodiesel manufacturing, sampling, testing, blending, storage, shipping, distribution

ASTM Grade Fuel, BQ-9000 Companies

BQ-9000 Status

• Since 2005, there has been a substantial increase in interest in the NBB’s BQ-9000 Quality Program

• There are now three BQ-9000 designations:– Producer (make it to spec)– Marketer (buy spec, keep it in spec, blend it right)– Certified Laboratories (test it to ensure it is in spec)

• We now have 60 total companies BQ-9000 certified • (37 producers, 23 marketers)• 75-80% of the biodiesel volume in the U.S. is now made by BQ-9000

producers, and more certifications are in process • Many OEMs are now either requiring or strongly encouraging BQ-9000

UPDATE THESE NUMBERS

•Under guidance of B20 Fleet Evaluation Team (OEM’s, NREL, NBB)

•Samples obtained nationwide from biodiesel blenders (27 samples)

•85% of samples tested met the ASTM D6751 specification

Four samples failed with high levels of:

•phosphorus (lube oil contamination?)

•total glycerin•acid number•acid number and total glycerin

2004 B100 Quality Survey

2006 Quality survey

•A subcontractor visited the site of a biodiesel blender, usually a terminal operator or jobber, to collect the B100 sample

•32 B100s, 6 B99s, and 1 B50

59% of B100 samples tested fail the D6751 specificationImportantly, 30% fail total glycerin – immediate operational problems in cold weatherOther issue of concern is 20% failure rate for Na+KCompares to 15% failure rate in 2004 surveySamples were collected randomly, not on production volume basis

Biodiesel, based on production volume, may have different failure rate Poor quality batch may have contaminated larger fuel lot

• Collect B100 samples directly from producers and analyze for properties most likely to impact engine performance and emission control systems– Flash point, oxidation stability, acid value, free and total

glycerin, cloud point, Na+K, Ca+Mg, P, water & sediment• First survey that will link test results to production

volume• Results presented at recent NBB meeting

2007 B100 Quality Survey

Survey Results

• 56 out of 107 producers participated in 2007 survey or 70% of the 2007 US market –Reasons for not participating are likely due to lack of feedstock availability

• Wide variety of feedstocks represented • Meeting the specification is independent of producer

size or feedstock • Small producers failed specifications more often than

medium or large producers • –Small producers: 28% of samples passed –Medium

producers: 68% of samples passed –Large producers: 94% of samples passed

How do you ensure quality?

Biodiesel Fuel Quality is determined by: 1. Feedstock quality 2. Production process 3. Post-Reaction monitoring 4. Analytical Capability5. Handling and Storage

**CRITICAL

Critical Parameters

Flashpoint, °C or Alcohol ContentAcid Number, mg KOH/gTotal and Free Glycerin, % massWater and Sediment, volume %Cloud point, °COxidative Stability, hr Sulfur, ppmVisual appearanceCold Soak Filtration

Flashpoint

Method ASTM D 93• Changed 2007- Limit: 93ºC minimum • Temperature • A sample is heated in a close vessel and ignited. When the sample burns, the

temperature is recorded. Alcohol Control

• One of the following must be met:

1. Methanol content EN 14110:

0.2 max % volume

2. Flash point D 93 : 130 min °C

Flashpoint

• Measures the temperature at which the vapors above the liquid can be ignited.

• Primarily used to determine whether a liquid is flammable or combustible

• Flashpoint is important for safety and hazard rating • Both DOT and OSHA say that any liquid with a flash point below

100F is flammable• ASTM D 93 is most common test for diesel fuels.• Can also be used to identify contamination from other fuels.• No. 1 = 38°C, No. 2 = 52°C

Flashpoint

Acid Number

• Test Method ASTM D 664• Limits: 0.5 mg KOH/g

maximum• pH sensitive electrode• May also be determined

using indicators

Sulfur Content• Sulfur can impact engine wear and deposits due varying

levels• Sulfur in diesel will now harm new emission control devices

of 2007 & newer vehicles• Sulfur burns to sulfur dioxide and sulfur trioxide, which can

combine with water to form sulfuric acid.• Small droplets of sulfuric acid and other sulfates contribute

to particulate emissions.• Sulfur is limited by the EPA for both on & off road diesel

fuels: In 1993: Reduced from 5000 ppm to 500 ppmIn 2006: Reduced from 500 ppm to 15 ppm

Sulfur Testing

• ASTM D 129 was traditional method but did not have sensitivity for new low sulfur fuels. (Bomb method)

• ASTM D 2622, X-Ray Spectrometry, is more sensitive but may not be adequate for 15 ppm diesel fuels.

• ASTM D 5453• Limits: 0.05 % mass maximum• S oxidized to SO2 at high temperatures

• UV fluorescence of emitted gases SO2 SO2* SO2

• S limits dictated by environmental considerations (S15 or S500)

• EPA regulations• Feedstock variation

Low temperature Operation

• Cloud point is the measurement of low temperate operation

• It dictates the temperature at which fuel first starts to crystallize and wax up when cooled

• Cloud point can predicate fuel filter clogging in some fuel delivery systems, but not all

• Other Low temp tests include:CFPP: Cold Filter Plugging PointLTFT: Low Temperature Flow TestPour Point and Cold Soak Filtration Test

Cloud Point

• Test Method ASTM D 2500• Limits: No established limits• Reported in ºC• Sample cooled and examined visually until first cloud appears.• Indicates the lowest temperature at which fuel is usable.• Generally higher than diesel.

Cloud Point & CFPP

Cloud Point

• No specific value is given in ASTM D975.• Requirements vary depending on geography.• 10th percentile temperature map

corresponds to the minimum temperature that would be reached no more than 3 days out of 30 for the month. 

• ASTM D 975 contains similar maps for other low temperature months in the United States.

Cold weather operation

• Wax molecules in diesel fuel and biodiesel tend to crystallize at low temperatures.

• Crystals agglomerate to form large masses.• This can cause filter plugging and eventually the fuel will

become a solid mass.• Soy biodiesel gels at approximately 32°F • #2 petroleum diesel fuel gels at 10 to 14 °F. • Biodiesel from saturated/tallow feedstocks can gel as

high as 50-55°F.• In contrast, petroleum diesel fuel is a mixture of

hundreds of different compounds that solidify at very different temperatures. So, even if some compounds crystallize at a relatively high temperature, many other compounds will stay liquid to a much lower temperature.

• Watch your soap & water content!

Water & Sediment

• Method D 2709• Limit of 500ppm, examining the free

water content • 100 mL of sample are centrifuged at 800

rcf for 10 min at 21° to 32°C in calibrated tube.

Water and Sediment

• Measures free, not emulsified,

water and insoluble particles.• Uses a centrifuge and cone-shaped

or pear-shaped bottles.• Total volume of water and

sediment must be < 0.05%. (500 ppm)• Contamination issue in supply line• Engine impact: Filter plugging, fuel

injection system wear, and corrosion, and opportunity for microbial growth

Karl Fischer :

Moisture Determination

•Biodiesel can absorb 1500 ppm of water while diesel only 50 ppm.•Free water can cause corrosion of fuel injection parts.•Housekeeping issue•Precipitates above cloud point

Cold Soak Filtration

• Developed in response to questions about precipitates above the cloud point

• Character of precipitates may vary with feedstock

• Method is now incorporated in the D6751

-6°C

-10°C -12°C

-8°C

Cold Soak cont.

• Preheat fuel at 40°C for 3 hours to remove thermal memory then hold at room temp for 24 hours

• Soak 300 mL sample at 4°C for 16 hours and let return to room temperature

– Time will vary with degree of saturation of feedstock

• Filter fuel using 0.7m filter and constant vacuum

• Record time to filter fuel– If fuel does not filter, record time

stopped and volume filtered

Sulfated Ash

• Test Method ASTM D 874• Limits: 0.020 % mass maximum• Sample ignited and burned • Ash + carbon (C removed by H2SO4)• Indication of concentration of metal

additives (Ba, Ca, Mg, Na, K, Sn, Zn)• More than 0.020 % indicates residual

soap & catalyst

Total & Free Glycerin

• Test Method ASTM D 6584• Limits: 0.020 % mass free glycerin• 0.240 % mass total glycerin• Gas Chromatography with FID detection• Quantifies glycerol, mono-, di- and triglycerides

ASTM D6584

• Measured with gas chromatograph (ASTM D6584) and requires a skilled operator.

• Saturated monoglycerides have very low solubility in biodiesel.

• If too high, there may be problems with fuel filter plugging and fuel stability.

Good Conversion

Oxidation Stability

• Equipment: Rancimat or OSI• Method: EN 14112; 3 minimum hours • Equipment cost: approximately 17- 20k • Products of oxidation in biodiesel are various acids or

polymers, can cause fuel system deposits and lead to filter plugging & fuel system malfunctions.

• Additives can improve the oxidation stability performance of biodiesel.

Fuel Oxidation

• Biodiesel will react with oxygen from the air to form polymers, acids, etc.

• Acids: – Presence indicated by increasing Acid Value– Cause corrosion of metal components– Corrosion can be aggravated by water

• Polymers:– Sediments that can plug fuel filters and coat metal

surfaces

Thermal & Oxidative Stability

• Chemical degradation occurs with contact with oxygen for long periods or at high temperatures.

• Oxidation of diesel fuel can form insolubles and peroxides

• Peroxides increase deposits and gumming on fuel pumps and injection systems

• Filter plugging will also occur• ASTM D975 now specifies a

stability parameter

Biodiesel Fuel Stability

• The biodiesel specification contains parameters for insuring adequate fuel stability for normal applications

• The shelf life of biodiesel blends is recommended by NBB as 6 months

• Stability additives available on the open market

Class I & II metals

Calcium & Magnesium & Sodium & Potassium can be in biodiesel as abrasive solids or soluble metallic soaps.

Solids contribute to injector, fuel pump, piston, and ring wear, & engine deposits.

Soluble metallic soaps have little effect on wear, but filter clogging & engine deposits

These compounds may also be collected in exhaust particulate removal devices

Less Critical Parameters

• Cetane• Distillation Temperature• Viscosity• Carbon Residue• Phosphorus• Copper Strip Corrosion

Cetane Number

• Measures the readiness of a fuel to auto-ignite.• High cetane means the fuel will ignite quickly at the

conditions in the engine (does not mean the fuel is highly flammable or explosive).

• Most fuels have cetane numbers between 40 and 60.• ASTM D 975 requires a minimum cetane number of 40• Premium Diesel fuel typically has a cetane of 47• ASTM methods are ASTM D-613 (ISO 5165) and D-

6890

Cetane

• Cetane engine shown above from petroleum testing facility• Ignition Delay: the period that occurs between the start of fuel

injection and the start of combustion; the higher the cetane number, the shorter the ignition delay and the better the quality of combustion.

Low Cetane Impact

Poor Ignition QualityLong ignition delay

Abnormal CombustionPossible High Combustion Pressure

Increased Engine stressExcessive Engine Knock

Smoke on Cold start

Cetane Index

• Cetane index is used as a substitute for the cetane number.

• The cetane index is calculated based on the fuel's density and boiling range.

• Two methods used ASTM D-976 or D-4737. • Cetane improvers that may be added are not

accounted for in the index

Boiling Point and Volatility

• Diesel fuel volatility needs vary for engine load, size, & speed

• Buses & trucks benefit from more volatile fuel

• ASTM D975 sets a min-max range

• Defines the upper and lower limits for 90% distilled point.

– No. 1 diesel: no lower limit, upper = 288 C– No. 2 diesel: lower limit = 282 C, upper = 338 C.

• 282C - 338C

90% Distillation Temperature

• Volatility or Boiling Point is controlled by the Distillation specification or T90

• Primarily used to separate diesel fuels into different grades. • Limits the amount of wax allowed in No. 1• If distillation temperatures are too low, then the fuel may

have difficulty meeting the flashpoint requirement.• If distillation temperatures are too high, then there is an

increased tendency of the fuel to deposit on the cylinder wall, where it can be swept down past the rings and into the lube oil.

Viscosity

• Low viscosity = power loss, component wear due to injector leaking or injection pump leak-down

• Low viscosity = poor lubrication ability

• High viscosity = Poor fuel dispersion, i.e. improper injector spray pattern

• High viscosity = high pump resistance and early pump failure

• Critical property for fuel injection system performance

• Measured with ASTM D 445.• #1 diesel fuel = 1.3 – 2.4 mm2/s• #2 diesel fuel = 1.9 – 4.1 mm2/s

Carbon Residue

• Measure of a diesel fuel’s tendency to form engine deposit

• Tests basically involve heating a sample of fuel to a temperature where the fuel will pyrolyze (decompose without oxygen), leaving a carbon-rich deposit (about 500°C)

• Test is frequently done on the 10% residue of fuel distillation.

• Limitation is 0.35 mass percent for No. 2 D• Limitation is 0.15 mass percent for No. 1 D

Ramsbottom Carbon Residue

• There are many tests for carbon residue:– Ramsbottom (D 524)– Conradson (D 189)– Micro Method (D 4530)

• Diesel fuel specification requires Ramsbottom• Carbon reside can vary with refinery processes

Ash

• Abrasive Solids• Soluble metallic soaps• Originates from

inorganic fuel components

• D 975 requires ash to be < 0.01%, by mass

• Injector & Fuel pump wear

• Piston and Ring wear• Solids = engine deposits• Low ash lubricating oils

- NEW

Copper Strip Corrosion

• Used to predict problems with copper, brass, or bronze components in a fuel system

• A measure of corrosiveness • Polished copper strip is placed in fuel for 3 hours at

50°C, then cleaned with a solvent and inspected for tarnish or corrosion.

• The strip is given a score between 1 and 4 with subdivisions indicated by letters, i.e. 2c means moderate tarnish with lavender coloring.

• Diesel fuel is allowed to be No. 3, which allows all tarnish but no actual corrosion.

Lubricity

• Lubricity test methods are continually improving and being evaluated

• Most common tests available to test lubricity: – SLBOCLE (scuffing load ball on

cylinder lubricity evaluator)• ASTM D 6078-99

– HFRR (high frequency reciprocating rig)

• ASTM D 6079-99• D975 points to the HFRR test• Limitation is 520 micron max of

wear at 60C

SLBOCLE

• SLBOCLE “ Scuffing Load Ball-On Cylinder Lubricity Evaluator”

• Steel ball bearing on a steel rotating-ring• Immersed in the test fluid• Weight is applied until a “scuff” mark is

seen on the rotating ring• Tangential force recorded• High Friction coefficient = scuffing• 3100 grams without scuffing passes the

SLBOCLE. (SWRI)

HFRR

• High Frequency Reciprocating Rig (HFRR)

• A steel ball • Reciprocated (1mm) • 200g load at 50 Hz for 75 minutes• 2 mL of Fuel• Adjust to 25 °C or 60 °C (77 °F or

140 °F– 60°C preferred

• Ball contacts test disk (in fuel)

Enhanced Lubricity

Ultra-low Sulfur Diesel

0100200300400500600700800

0.0 1.0 2.0 3.0 4.0 5.0

Biodiesel Blend (%)

HFRR WSD (micron)

• Equipment benefits– Superior lubricity– B2 has up to 66% more

lubricity than #2 Diesel

• EPA required sulfur reduction in diesel

• No overdosing concerns

Density

• Specific gravity – ratio of the density of the fuel to the density of water.– #1 diesel = 0.81– #2 diesel = 0.840 – 0.855

• API gravity – common in petroleum industry. API = 141.5/SG – 131.5

• Can be one indicator of fuel economy, power, deposits, wear, and exhaust smoke

• For example, a low API (or high density) has bore BTUs/gallon which could improve fuel economy

Energy Content

• Heating value of the fuel

• Not specified by ASTM• Typically expressed as

BTUs/gallon• Engine Manufacturers• Impact fuel ecomony• No. 2 D can vary up 15%

between supplier & season

No. 2 D 130,000 BTUs/gallon

Gasoline 114,200 BTUs/gallon Biodiesel (B100) 120,000 BTUs/gallon

Non ASTM tests

• Saftest • Completeness of Reaction (3/27

Methanol Test)• Soap test: AOCS method• Wilkes Infraspec• Paradigm Sensors• Fleet Biodiesel• pHLip Test• Wika Water test• Microbial growth, algae-x

MP Biomedicals

Completion of Reaction

• Dissolve 3 ml of biodiesel in 27 ml of methanol.• The biodiesel should be fully soluble in the methanol

forming a clear bright phase.• If you observe un-dissolved material at the bottom of

the sample the reaction did not proceed to completion• Each ml of un-dissolved material corresponds to 4% by

volume.

0.2139 Bound Glycerin

Although cloudy, there were no droplets of precipitate.

0.0900 Bound Glycerin

Crystal clear, no cloudiness or precipitate.

Samples Passing 3/27

0.9256 Bound GlycerinNote the falling droplets of unreacted oil.

Samples Failing 3/27

1.8260 Bound Glycerin

Biodiesel Conversion Test

Acid Number Qualitative Tests

AOCS- Soap Content

• Gels at ambient temperature as little as 5%• Cause problems with glycerol separation and washing• Soap can be split by acidulating• Soap is usually clear and very viscous• Methanol will act as a cosolvent and keep soap in solution with the

biodiesel• High soap levels = high sulfated ash number• High FFA and water content lead to soap formation in process

Soap Method

Titrating from blue/green to straw yellow….

• Insert info on BASF QTA method

AOCS Method for QTA

Wilkes InfraSpec

measures percent biodiesel in diesel fuel, ethanol in gasoline, water in ethanol as well as total glycerides during the biodiesel

pass/fail determination in less than 5 minutes.

Wilkes Infra-Spec

Paradigm Sensors

* Paradigm Sensors’i-SPEC™ tests TOTAL GLYCERIN in blended fuels (B6-B20), which is in accordance with ASTM proposal that the biodiesel portion of the fuel must meet ASTM 6751 prior to blending.

Fleet Biodiesel

Cytoculture - pHlip tst

Wika Water Test

• Certain varieties of bacteria and fungi can grow in diesel fuel tanks.• Growth occurs at the interface of the fuel and water at the bottom of

the fuel tank.• Water must be drained from tank bottoms on a regular basis.• ULSD• Biocides are available to control microbial growth.

– Dead microbes can still plug filters.– Water elimination and prevention is preferred over treatment.

Microbial growth

Microbial Growth

• Microbes are bacteria or fungus that live and propagate in fuel at the fuel/water interface.

• Water needed to live—no water, no bugs.

• Hydrocarbons in petrodiesel or biodiesel provide the food and the water provides the oxygen.

• This environment is needed for living, growth, and reproduction.

• The filters with microbial contamination often had an odor different from the normal fuel smell.

Exposure to AirExposure to Air

• Enters through vent pipes and contains large amounts of moisture.

• Generally displaces the fuel as tank is emptied.

• It is not practical to keep air from entering the tank.

• Will increase the oxidation of fuel.

• Do not store fuels for long periods of time in partially empty tanks without stabilizers.

• Consider desiccant dryers.

Bacteria Growth

Fungal Growth

• Microbial growth – ULSD & moisture

Treat your storage tanks for moisture/biocide • Incomplete reaction • Aged fuel • Cold Flow• Low energy content (not harmful)

Fuel filter plugging is the most common operational

issue

Operational issues

Certificate of Analysis

Biodiesel Quality Standard

ASTM D 6751 Standards• Fuel quality is critical for

proper functioning• Standards ensure

satisfactory operation in diesel engines

BQ 9000 Certification• Certifies biodiesel

producers and markers• Feeling of confidence for:

– Biodiesel Producers– Engine and Vehicle

Manufacturers– Distributors– Consumers

Steps to Maintaining Fuel

• Store Fuel in Clean, Dry Dark Environment• Keep Tank Topped off to eliminate head space• Monitor hoses, fill/vapor caps, gaskets for leaks• Storage in on-site tanks should be limited to less

than 6 months.• Once a year send your fuel to lab to be tested for

microbial contamination

• Purchase fuel from known quality producer• On-site and in-process analysis is essential• Watch for residual contamination• Correct product handling and storage procedures is

essential• Final product must meet the current revision of ASTM

D 6751

In Summary

Biodiesel Use & Handling

• Refer to the Biodiesel Use & Handling Guidelines available on the Biodiesel Training Toolkit and at: http://www.nrel.gov/vehiclesandfuels/pdfs/43672.pdf

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Fuel Quality resources

• www.biodiesel.org• http://www.bq-9000.org/• www.me.iastate.edu/biodiesel• http://www.uidaho.edu/bioenergy/index.html• http://www.cytoculture.com/• http://www.biodieselmagazine.com

Biodiesel Resources

www.biodiesel.org•Biodiesel Training Toolkit

•News Releases & Information Resources

•Technical Library, Spec Sheets & Videos

•OEM Warranty Positions on Biodiesel

• U.S. Diesel Vehicle List

www.BQ-9000.org •Listing of BQ-9000 Certified Companies

www.biotrucker.com•Listing of BioTrucker retail sites

www.biodieselautomotive.org•Dedicated to information exchange for biodiesel & diesel technicians

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Thank You!Questions…?

Rachel BurtonOEM Diesel Technician Training Programwrenchwench@blast.comTel: 919-444-3495

Call NBB at 1-800-841-5849Visit www.biodiesel.org

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