Biodiesel
In the Northeast, restaurant waste grease is increasingly being used as the base material to produce biodiesel for use in home furnaces and personal vehicles. This is a beneficial re-use of a material that otherwise might end up in landfills or be shipped elsewhere. Use of biodiesel reduces greenhouse gas emissions of carbon dioxide and particulate matter that are associated with major health impacts, including cancer. Biodiesel also reduces hydrocarbon emissions that contribute to the formation of ground level ozone, as well as carbon monoxide, a poisonous gas associated with fuel combustion. However, biodiesel home brewing is not entirely risk free. Production of biodiesel does cause certain environmental problems, health and safety risks and social considerations. We want to make you aware of these concerns so that you can make informed choices, should you choose to produce your own biodiesel fuel.
What is Biodiesel?
Biodiesel is a domestically produced, renewable fuel that can be used in place of petroleum diesel. In the United States most biodiesel is made from soy oil, but it can also be made from other vegetable oils, including rapeseed (canola), palm tree, olive, peanut, safflower, sunflower, and castor, and even some strains of algae. It can also be made from used cooking oil.
Regardless of the base material, production of biodiesel includes the handling and use of an alcohol (usually methanol) and a strong base (usually sodium hydroxide or potassium hydroxide, also known as lye). Environmental concerns that must be addressed include fugitive emissions of methanol, the ultimate disposal of the by-product glycerin, and the generation and disposal of wastewater containing free fatty acids that have a high biochemical oxygen demand, or BOD, that can remove oxygen from water bodies and harm aquatic life. Keep in mind that glycerol is a fatty acid. If you pour it down the drain, it may solidify and clog your drain system.
You should note that a B20 or lower blend of biodiesel can be used in most diesel engines with little or no modifications. However, higher concentrations of biodiesel, which may be the end result of home brewing, may require some minor changes to injection rates and vehicle timing, and may have a detrimental effect on natural rubber hoses and gaskets.
More about Biodiesel:
- Biodiesel Fact Sheet - Before you consider making biodiesel at home ... Read this fact sheet.
