Biodiesel

What is Biodiesel?

Biodiesel is Diesel fuel made from vegetable oils and animal fats. Another term for biodiesel is fatty acid methyl ester. Biodiesel is made from triglycerides (fats and oils). The fats and oils resemble a three legged stool. Each leg is an ester, the seat is a glycerin. The esters in the fats and oils are removed in the presence of a catalyst and combined with methanol. This results in a fatty acid methyl ester. The glycerin is removed from the fatty acid methyl ester and used for other products. The whole process is called transesterification.

For more information about Biodiesel advantages, applications, news and policy, please visit the National Biodiesel Board website.

Benefits and Disadvantages

Biodiesel is the easiest path to Greenhouse gas mitigation

You can keep your existing equipment. Biodiesel requires precautions as opposed to recapitalization. You may need to buy some fuel lines, and clean storage tanks, both are minor costs. But you will not require any other special equipment. It can be used to extend the life of particle traps.

Biodiesel from used cooking oil has a carbon intensity of 14 and replaces diesel that has a carbon intensity of 94.

Carbon intensity is grams of carbon dioxide per megajoule of energy. Multiply carbon intensity times energy density to obtain tons of carbon diverted.

Communities seeking the goal of greenhouse gas reduction or even carbon neutrality will get more for their environmental dollar by transitioning to biodiesel. Because biodiesel is essentially pour and go, and can be used on all diesel engines.

Western States Advantage

Western States Oil is virtually unique among petroleum jobbers. Western purchases used cooking oil from restaurants in the Northern California Area, and contracts productions with California based biodiesel plants. The fuel is then made available for California based truck fleets and individual consumers. We work with fleet managers and vehicle owners to ensure that their biodiesel experience is seamless.

Whether our biodiesel is derived from soy bean oil or from restaurant grease, Western States Oil has a quality assurance program that ensures our product exceeds the ASTM (American Society Testing and Materials) standards. Our quality is high because we track and monitor our biodiesel from source to use.

How to Transition to Biodiesel (long version)

On a vehicle

  • Ensure that the fuel tank is clean
  • Ensure that your fuel lines are post 1994 or that they are replaced with viton or teflon
  • Start using it just prior to a scheduled fuel filter change

Over a fleet

  • Appoint a “go-to” person or project manager
  • Ensure the parties in the logistics chain are either BQ-9000 qualified or compliant
  • Ensure that the fuel is kept free of dirt, water, and other contaminants in the logistics chain
  • Clean your storage tank using a fuel polishing service and ensure the sides of the tank are clean too
  • Transition the vehicles properly (see above)

Communicate with the supplier on a regular basis

How to Transition to Biodiesel (short version)

Appoint a go-to person

Get the rubber out

Keep the water out

Most diesel vehicles built after 1994 have a material compatibility with biodiesel. Treat biodiesel in the same manner as you would treat diesel: install desiccating filters to keep water vapor out of storage tanks.

Biodiesel has many positives

Better Emissions

  • It reduces Particulates by half
  • It reduces Sulfur Compounds, Mutagens, and Carcinogens by 80% to 90%
  • It reduces Polycyclic Aromatic Hydrocarbons by 80%
  • It reduces Carbon Monoxide by half

Greater Lubricity

  • It can replace sulfur in ULSD

Biodegradability

  • It degrades in the environment at the same rate as sugar

Non-toxicity

  • It is as toxic as table salt and is the only alternative fuel to pass EPA tier two testing

No New Equipment

  • You can keep your existing equipment. Biodiesel requires precautions as opposed to recapitalization. You may need to buy some fuel lines, but you will not require any other special equipment. It can be used to extend the life of particle traps.

Reduce Opacity

  • Biodiesel reduces exhaust opacity significantly and will help a vehicle fleet comply with Opacity Regulations with little or no extra cost.

Few Negatives

  • Appoint a “go-to” person or project manager
  • Ensure the parties in the logistics chain are either BQ-9000 qualified or compliant
  • Ensure that the fuel is kept free of dirt, water, and other contaminants in the logistics chain
  • Clean your storage tank using a fuel polishing service and ensure the sides of the tank are clean too
  • Transition the vehicles properly (see above)

Communicate with the supplier on a regular basis

 

Emissions

Average Biodiesel Emissions Compared to Conventional Diesel,
According To EPA

Emission Type

B100

B20

Sulfates

-100%

-20%

PAH (Polycyclic Aromatic Hydrocarbons)*

-80%

-13%

Ozone potential of speciated HC

-50%

-10%

* Average reduction across all compounds measured

Source: National Biodiesel Board Fuel Fact Sheet

Tailpipe Emission Changes with Biodiesel Fuels

Emission Type

B100*

B20**

Carbon Monoxide

-43.2%

-12.6%

Hydrocarbons

-56.3%

-11.0%

Particulates

-55.4%

-18.0%

Nitrogen oxides

+5.8%

+1.2%

Air toxics

-60% to -90%

-12% to -20%

Mutagenicity

-80% to -90%

-20%

Carbon dioxide***

-78.3%

-15.7%

* Average of data from 14 EPA FTP Heavy Duty Test Cycle tests, variety of stock engines

** Average of data from 14 EPA FTP Heavy Duty Cycle tests, variety of stock engines

*** Life cycle emissions

Source: Biodiesel Handling and Use Guidelines, K. Shane Tyson, NREL/TP-580-30004

Selected Fuel Properties
for Diesel and Biodiesel Fuels

Fuel Property

Diesel

Biodiesel

Fuel Standard

ASTM D975

ASTM 6751

Fuel composition

C10-C21 HC

C12-C22 FAME

Lower Heating Value, Btu/gal

131,295

117,093

Kin. Viscosity, @ 40 C

1.3-4.1

1.9-6.0

Specific Gravity kg/l @ 60 F

0.85

<0.88/td>

Density, lb/gal @ 15C

7.079

7.328

Water, ppm by wt

161

.05% max

Carbon, wt %

87

77

Hydrogen, wt %

13

12

Oxygen, by dif. wt %

0

11

Sulfur, wt %

.05 max

0.0 – 0.0024

Boiling Point, C

188-343

182-338

Flash Point, C

60-80

100-170

Cloud Point, C

-15 to 5

-3 to 12

Pour Point, C

-35 to -15

-15 to 10

Cetane Number

40-55

48-65

Stoichiometric:

Air/Fuel Ratio wt./wt.

15

13.8

BOCLE Scuff, grams

3,600

>7,000

HFRR, microns

685

314

Source: Biodiesel Handling and Use Guidelines, K. Shane Tyson, NREL/TP-580-30004