What is Biodiesel

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					What is Biodiesel?
Biodiesel is the name for a variety of ester-based oxygenated fuels made from
vegetable oils or animal fats. The concept of using vegetable oil as a fuel dates back to
1895 when Dr. Rudolf Diesel developed the first diesel engine to run on vegetable oil.
Diesel demonstrated his engine at the World Exhibition in Paris in 1900 using peanut
oil as fuel.

Properties of Biodiesel

Today’s diesel engines require a clean-burning, stable fuel that performs well under a
variety of operating conditions. Biodiesel is the only alternative fuel that can be used
directly in any existing, unmodified diesel engine. Because it has similar properties to
petroleum diesel fuel, biodiesel can be blended in any ratio with petroleum diesel fuel.
Many federal and state fleet vehicles in USA are already using biodiesel blends in their
existing diesel engines.
The low emissions of biodiesel make it an ideal fuel for use in marine areas, national
parks and forests, and heavily polluted cities. Biodiesel has many advantages as a
transport fuel. For example, biodiesel can be produced from domestically grown
oilseed plants such as canola. Producing biodiesel from domestic crops reduces the
Australia's dependence on foreign petroleum, increases agricultural revenue, and
creates jobs.

Key Advantages of Biodiesel:

1. Biodiesel is the only alternative fuel in the US to complete EPA Tier I Health
   Effects Testing under section 211(b) of the Clean Air Act, which provide the most
   thorough inventory of environmental and human health effects attributes that
   current technology will allow.

2. Biodiesel is the only alternative fuel that runs in any conventional, unmodified
diesel engine. It can be stored anywhere that petroleum diesel fuel is stored.

3. Biodiesel can be used alone or mixed in any ratio with petroleum diesel fuel. The
most common blend is a mix of 20% biodiesel with 80% petroleum diesel, or "B20."

4. The lifecycle production and use of biodiesel produces approximately 80% less
carbon dioxide emissions, and almost 100% less sulphur dioxide. Combustion of
biodiesel alone provides over a 90% reduction in total unburned hydrocarbons, and a
75-90% reduction in aromatic hydrocarbons. Biodiesel further provides significant
reductions in particulates and carbon monoxide than petroleum diesel fuel. Biodiesel
provides a slight increase or decrease in nitrogen oxides depending on engine family
and testing procedures. Based on Ames Mutagenicity tests, biodiesel provides a 90%
reduction in cancer risks.

5. Biodiesel is 11% oxygen by weight and contains no sulphur. The use of biodiesel
can extend the life of diesel engines because it is more lubricating than petroleum
diesel fuel, while fuel consumption, auto ignition, power output, and engine torque are
relatively unaffected by biodiesel.

6. Biodiesel is safe to handle and transport because it is as biodegradable as sugar, 10
times less toxic than table salt, and has a high flashpoint of about 125°C compared to
petroleum diesel fuel, which has a flash point of 55°C.

7. Biodiesel can be made from domestically produced, renewable oilseed crops such as
soybeans, canola, cotton seed and mustard seed.

8. Biodiesel is a proven fuel with over 30 million successful US road miles, and over 20
years of use in Europe.

9. When burned in a diesel engine, biodiesel replaces the exhaust odor of petroleum
diesel with the pleasant smell of popcorn or french fries.

10. The Congressional Budget Office, and Department of Defense, US Department of
Agriculture, and others have determined that biodiesel is the low cost alternative fuel
option for fleets to meet requirements of the Energy Policy Act.
Biodiesel is the first and only alternative fuel to have a complete evaluation of
emission results and potential health effects submitted to the U.S. Environmental
Protection Agency (EPA) under the Clean Air Act Section 211(b). These programs
include the most stringent emissions testing protocols ever required by EPA for
certification of fuels or fuel additives in the US. The data gathered through these tests
complete the most thorough inventory of the environmental and human health effects
attributes that current technology will allow. A survey of the results is provided in the
table below.

Emission Type                                                   B100  B20
Total Unburned Hydrocarbons                                     -93%  -30%
Carbon Monoxide                                                 -50%  -20%
Particulate Matter                                              -30%  -22%
NOx                                                             +13%  +2%
Sulfates                                                        -100% -20%*
PAH (Polycyclic Aromatic Hydrocarbons)**                        -80%  -13%
nPAH (nitrated PAH’s)**                                         -90%  -50%***
Ozone potential of speciated HC                                 -50%  -10%
* Estimated from B100 result
** Average reduction across all compounds measured
*** 2-nitroflourine results were within test method variability

The overall ozone (smog) forming potential of biodiesel is less than diesel fuel.

The ozone forming potential of the speciated hydrocarbon emissions was nearly 50
percent less than that measured for diesel fuel.

Sulphur emissions are essentially eliminated with pure biodiesel.

The exhaust emissions of sulphur oxides and sulfates (major components of acid rain)
from biodiesel were essentially eliminated compared to sulphur oxides and sulphates
from diesel.

Criteria pollutants are reduced with biodiesel use.
The use of biodiesel in an unmodified Cummins N14 diesel engine resulted in
substantial reductions of unburned hydrocarbons, carbon monoxide, and particulate
matter. Emissions of nitrogen oxides were slightly increased.

Carbon Monoxide

The exhaust emissions of carbon monoxide (a poisonous gas) from biodiesel were 50
percent   lower     than     carbon    monoxide     emissions     from     diesel.

Particulate Matter

Breathing particulate has been shown to be a human health hazard. The exhaust
emissions of particulate matter from biodiesel were 30 percent lower than overall
particulate matter emissions from diesel.


The exhaust emissions of total hydrocarbons (a contributing factor in the localized
formation of smog and ozone) were 93 percent lower for biodiesel than diesel fuel.

Nitrogen Oxides

NOx emissions from biodiesel increase or decrease depending on the engine family and
testing procedures. NOx emissions (a contributing factor in the localized formation of
smog and ozone) from pure (100%) biodiesel increased in this test by 13 percent.
However, biodiesel’s lack of sulphur allows the use of NOx control technologies that
cannot be used with conventional diesel. So, biodiesel NOx emissions can be
effectively managed and efficiently eliminated as a concern of the fuel’s use.

Biodiesel reduces the health risks associated with petroleum diesel.

Biodiesel emissions showed decreased levels of PAH and nitrited PAH compounds
which have been identified as potential cancer causing compounds. In the recent
testing, PAH compounds were reduced by 75 to 85 percent, with the exception of
benzo(a)anthracene, which was reduced by roughly 50 percent. Targeted nPAH
compounds were also reduced dramatically with biodiesel fuel, with 2-nitrofluorene
and 1-nitropyrene reduced by 90 percent, and the rest of the nPAH compounds
reduced to only trace levels.
                 Health Effects Testing
In June 2000, representatives of the U.S. Congress announced that biodiesel had
become the first and only alternative fuel to have successfully completed the Tier I and
Tier II Health Effects testing requirements of the Clean Air Act Amendments of 1990.
The soybean industry invested more than two million dollars and four years into the
health effects testing program with the goal of setting biodiesel apart from other
alternative fuels and increasing consumer confidence in biodiesel.

The first tier of health effects testing was conducted by Southwest Research Institute
and involved a detailed analysis of biodiesel emissions. Tier II was conducted by
Lovelace Respiratory Research Institute, where a 90-day sub-chronic inhalation study
of biodiesel exhaust with specific health assessments was completed.

Results of the health effects testing concluded that biodiesel is non-toxic and
biodegradable, posing no threat to human health. Also among the findings of biodiesel
emissions compared to petroleum diesel emissions:
• The overall ozone (smog) forming potential of exhaust emissions from biodiesel is
   50% less.
• The exhaust emissions of carbon monoxide (a poisonous gas and a contributing
   factor in the localized formation of smog and ozone) from biodiesel are 50% lower.
• The exhaust emissions of particulate matter (recognized as a contributing factor in
   the respiratory disease) from biodiesel are 30% lower.
• The exhaust emissions of sulphur oxides and sulphates (major components of acid
   rain) from biodiesel are complete eliminated.
• The exhaust emissions of hydrocarbons (a contributing factor in the localized
   formation of smog and ozone) are 95% lower.
• The exhaust emissions for aromatic compounds known as PAH and NPAH
   compounds (suspected of causing cancer) are substantially reduced for biodiesel
   compared to diesel. Most PAH compounds were reduced by 75% to 85%. All NPAH
   compounds were reduced by at least 90%.

The health effects testing results provide conclusive scientific evidence using the most
sophisticated technology available to validate the existing body of testing data. The
comprehensive body of biodiesel data serves to demonstrate the significant benefits of
biodiesel to the environment and to public health. This will lead to increase consumer
confidence and increased use of biodiesel. Since the majority of biodiesel is made from
soybean oil, a promising new market is materializing for soybeans.

                                                          Source: www.biodiesel.org.au

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