BIODIESEL
Description
Biodiesel is a liquid which varies in color — between golden and dark
brown — depending on the production feedstock. It mixes easily with water,
has a high boiling point and low vapor pressure. Typical methyl ester biodiesel
has a flash point of ~ 150 °C (300 °F). Biodiesel has a density of ~
0.88 g/cm³, less than that of water.Biodiesel has a viscosity similar to
petrodiesel, the current industry term for diesel produced from petroleum. It
has virtually no sulpher content and high lubricity, so is often used as an
additive to Ultra-Low Sulfur Diesel (ULSD) fuel.Much of the world uses a system
known as the "B" factor to state the amount of biodiesel in any fuel
mix: fuel containing 20% biodiesel is labeled B20, while pure biodiesel is referred
to as B100. It is common to see B99, since 1% petrodiesel is sufficiently toxic
to retard mold.
Advantages
Biodiesel is a renewable fuel that can be manufactured from vegetable oils,
animal fats, recycled restaurant greases, and some types of algae; it can be
produced locally in most countries. It is safe, biodegradable and reduces air
pollutants, such as particulates, carbon monoxide and hydrocarbons. Blends of
20 percent biodiesel with 80 percent petroleum diesel (B20) can generally be
used in unmodified diesel engines. Biodiesel can also be used in its pure form
(B100), but may require certain engine modifications to avoid maintenance and
performance problems.
Biodiesel
is biodegradable and non-toxic, and typically produces about 60% less net-lifecycle
carbon dioxide emissions, as it is itself produced from atmospheric carbon dioxide
via photosynthesis in plants. Its emissions of smog forming hydrocarbon are
65% less, although the Nitrogen Oxide emissions are about 10% greater than those
from petroleum-based diesel.Net-lifetime carbon dioxide emissions can actually
differ widely between fuels depending upon production methods of the source
vegetable oils and processing methods employed in their creation. It is therefore
debatable as to the extent that biodiesel reduces total carbon dioxide emissions
currently contributing to anthropogenic global warming compared to those from
petroleum-based diesel.
Biodiesel is a better solvent than standard diesel, as it 'cleans' the engine,
loosening petrodiesel deposits in the fuel lines, which can cause blockages
downstream in engines that have previously run for some time on petroleum diesel.
For this reason, car manufacturers recommend[citation needed] that the fuel
filter be changed more frequently for a few months after switching to biodiesel.
Most manufacturers release lists of the cars that will run on 100% biodiesel.
Distribution
Biodiesel can be distributed using today's diesel infrastructure as long as
minor adjustments are made, such as replacement of old solvent-prone fittings
and hoses, filtering of loosened fossil fuel varnishes, and prevention of the
growth of mold and care taken to prevent coagulation at colder temperatures.Its
use and production are increasing rapidly. Fuel stations make biodiesel readily
available to consumers across Europe, and increasingly in the USA and Canada,
and a growing number of transport fleets use it as an additive in their fuel.
Biodiesel is often more expensive to purchase than petroleum diesel but this
is expected to diminish due to economies of scale and agricultural subsidies
versus the rising cost of petroleum as reserves are depeleted.(1)
(1) Source : Wikipedia