Bio diesel is the name of a clean burning alternative fuel, produced from domestic, renewable resources. Bio diesel contains no petroleum, but it can be blended at any level with petroleum diesel to create a biodiesel blend. It can be used in compression-ignition (diesel) engines with little or no modifications. Bio diesel is simple to use, biodegradable, nontoxic, and essentially free of sulfur and aromatics. Bio diesel is produced from any fat or oil such as soybean oil, through a refinery process called transesterification. This process is a reaction of the oil with an alcohol to remove the glycerin, which is a by-product of bio diesel production. Fuel-grade bio diesel must be produced to strict industry specifications (ASTM D6751) in order to insure proper performance. Bio diesel is the only alternative fuel to have fully completed the health effects testing requirements of the 1990 Clean Air Act Amendments. Bio diesel that meets ASTM D6751 and is legally registered with the Environmental Protection Agency is a legal motor fuel for sale and distribution. Raw vegetable oil cannot meet bio diesel fuel specifications, it is not registered with the EPA, and it is not a legal motor fuel.
Bio diesel can be used as a pure fuel or blended with petroleum in any percentage. B20 (a blend of 20 percent by volume bio diesel with 80 percent by volume petroleum diesel) has demonstrated significant environmental benefits with a minimum increase in cost for fleet operations and other consumers. Bio diesel is the only alternative fuel to have fully completed the health effects testing requirements of the Clean Air Act. The use of bio diesel in a conventional diesel engine results in substantial reduction of unburned hydrocarbons, carbon monoxide, and particulate matter compared to emissions from diesel fuel. In addition, the exhaust emissions of sulfur oxides and sulfates (major components of acid rain) from bio diesel are essentially eliminated compared to diesel.
Of the major exhaust pollutants, both unburned hydrocarbons and nitrogen oxides are ozone or smog forming precursors. The use of bio diesel results in a substantial reduction of unburned hydrocarbons. Emissions of nitrogen oxides are either slightly reduced or slightly increased depending on the duty cycle of the engine and testing methods used. Based on engine testing, using the most stringent emissions testing protocols required by EPA for certification of fuels or fuel additives, the overall ozone forming potential of the speciated hydrocarbon emissions from bio diesel was nearly 50 percent less than that measured for diesel fuel. In general, the standard storage and handling procedures used for petroleum diesel can be used for bio diesel. The fuel should be stored in a clean, dry, dark environment. Acceptable storage tank materials include aluminum, steel, fluorinated polyethylene, fluorinated polypropylene and teflon. Copper, brass, lead, tin, and zinc should be avoided. Bio diesel can be operated in any diesel engine with little or no modification to the engine or the fuel system. Bio diesel has a solvent effect that may release deposits accumulated on tank walls and pipes from previous diesel fuel storage. The release of deposits may clog filters initially and precautions should be taken. Ensure that only fuel meeting the bio diesel specification is used.