How Biodiesel is Made Into Fuel

We have all been told that the world supplies of petroleum/crude oil are limited and won’t last forever – they’re not sustainable resources.  However, society these days is very dependent on the motorcar and other means of transport powered by the internal combustion engine.  A very straightforward solution to this conundrum is biodiesel.

What is Biodiesel?

Biodiesel is any diesel that has been refined from a source other than petroleum.  Biodiesel needs an oily substance to start with, which is then refined to make it usable by diesel engines – even regular diesel engines (however, modifications are needed to run a car on straight vegetable oil that hasn’t been refined).

Primary Sources of Biodiesel

Biodiesel can be sourced from:

• waste vegetable and other oil,
• waste tallow from animals,
• soybeans,
• corn (maize),
• jatropha (Buddha Belly plant),
• sunflower seeds,
• hemp (honestly, constable, I’m trying to grow it for biodiesel…),
• flax,
• palm,
• rapeseed (commonly called canola oil),
• algae.

Making Biodiesel Usable

To make the oil useable, it has to be purified by filtering, especially in the case of waste oil or tallow, and it has to have all the water removed from it, usually by heating it above 100 degrees celsius.  It then goes through a process of refining to get out all the unusable bits, such as alcohol (as a bonus, these alcohols may have potential to also be used as biofuel), and to remove the free fatty acids – otherwise you could end up with soap rather than biodiesel.

Biodiesel is usually blended with petroleum-based diesel at the petrol pump.  A “B10” mixture contains 10% biodiesel and 90% regular, while B100 is 100% biodiesel.  While cars can run on 100% biodiesel, this has an effect on performance a little (although you can bet your bottom dollar that car companies are working on this one) and biodiesel corrodes old rubber hoses and gaskets a bit more than regular – again, they’re working on this one.

Issues Around Using Biodiesel & Algae Oil

One of the issues surrounding the production of biodiesel is that growing crops for biodiesel uses arable land that could be used for food production, and this could lead to further problems with world hunger and rising food prices.  However, this is not a problem with algae biodiesel, as this can be grown on unproductive land using sewage (seriously!), nor with waste tallow and waste vegetable oil, as this is left over after it has been used for food  - a common source of waste vegetable (and other) oil is from fast food outlets. In fact, algae oil can even thrive off exhaust fumes from powerplants.