Delivering ethanol by pipeline is the most efficient option, but ethanol's affinity for water and solvent properties require the use of a dedicated pipeline or significant cleanup of existing pipelines to convert them into dedicated pipelines. Kinder Morgan ships batches of ethanol through its Central Florida Pipeline. More Ethanol Publications All Publications. More in this section Ethanol Production and Distribution Ethanol is a domestically produced alternative fuel most commonly made from corn.
Production The production method of ethanol depends on the type of feedstock used. Starch- and Sugar-Based Ethanol Production Most ethanol in the United States is produced from starch-based crops by dry- or wet-mill processing.
Cellulosic Production Making ethanol from cellulosic feedstocks—such as grass, wood, and crop residues—is a more involved process than using starch-based crops. Schematic of Fuel Distribution System Enlarge illustration. Ethanol Plants, Capacity, and Production. The higher the octane number, the more resistant the gasoline mixture is to knock. Doing so would increase vehicle efficiency and lower greenhouse gases through decreased petroleum consumption. In the early 20th century, automotive manufacturers were searching for a chemical that would reduce engine knock.
In , automotive engineers working for General Motors discovered that tetraethyl lead better known as lead provided octane to gasoline, preventing engine knock. While aromatic hydrocarbons such as benzene and alcohols such as ethanol were also known octane providers at the time, lead was the preferred choice due to its lower production cost.
Leaded gasoline was the predominant fuel type in the United States until the U. Environmental Protection Agency EPA began phasing it out in the mids because of proven serious health impacts. Early in its use as a fuel additive, health concerns were raised regarding the use of lead in gasoline. In , 15 refinery workers in New Jersey and Ohio died of suspected lead poisoning.
As a result, the Surgeon General temporarily suspended the production of leaded gasoline and convened a panel to investigate the potential dangers of lead use in gasoline.
Despite these warnings, the Surgeon General set a voluntary standard of lead content, which the refining industry successfully met for decades. It was not until the s, following extensive health research, that the devastating health impacts of low-level lead exposure were established.
The health impacts of lead exposure in children include anemia, behavioral disorders, low IQ, reading and learning disabilities, and nerve damage. In adults, lead exposure is associated with hypertension and cardiovascular disease. Prior to the lead phase-out in gasoline, the total amount of lead used in gasoline was over , tons per year. Congress passed the Clean Air Act in , setting in motion the formation of the EPA and, ultimately, the removal of lead from gasoline.
EPA estimates that between and , 68 million children were exposed to toxic levels of lead from leaded gasoline alone. The phase-out of lead from gasoline subsequently reduced the number of children with toxic levels of lead in their blood by 2 million individuals a year between and The EPA is formed and given the authority to regulate compounds that endanger human health.
Lead damages the catalytic converters used in these new vehicles to control tailpipe emissions. Catalytic converters are still used in vehicles today.
Lead is still used in some aviation fuels. Thanks to coordinated efforts, lead is now absent from gasoline in most of the world. Following the lead phase-out in the United States, the oil refining industry chose to construct additional refining capacity to produce octane from other petroleum products, rather than from renewable sources such as ethanol.
RFG has an increased oxygenate content, which helps it burn more completely. As a result, RFG lowers the formation of ozone precursors and other air toxics during combustion. Petroleum refiners were not required to use any particular oxygenate in RFG, but by the late s, a petroleum product, methyl tertiary butyl ether MTBE , was used in 87 percent of RFG due to its ease of transport and blending.
In the Midwest, ethanol was a more common component of RFG. Despite its success at reducing ozone precursors, MTBE was phased out of the gasoline pool due to concerns over its solubility in water, which resulted in the contamination of water resources in numerous states.
Currently, 30 percent of gasoline sold in the United States is reformulated gasoline. Ethanol is providing the additional octane required by RFG.
Department of Agricultural and Biosystems Engineering. NDSU Extension. Energy Accessibility. Info Share. References Bevill, K. Filed under: Ethanol. Feel free to use and share this content, but please do so under the conditions of our Creative Commons license and our Rules for Use. Box Fargo, ND
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