Ethanol how is it made

Most U. According to the U. The United States consumed nearly Ethanol, gasoline blendstock, and additives are delivered separately to fuel terminals where they are blended into fuel trucks for delivery to stations.

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. Flex fuel vehicles, which have modifications to the fuel systems, can use E85, which is a blend of up to 85 percent ethanol and 15 percent gasoline. With the modifications, these vehicles can use straight gasoline or any blend of ethanol up to 85 percent.

Ethanol can be fermented from many sources of starch, including corn, wheat, grain sorghum, barley, and potatoes, and from sugar crops such as sugar cane and sweet sorghum. Because there has been has been an abundant supply of corn, most of the ethanol made in the United States is from corn. Most of the ethanol is produced in the Midwest and Upper Midwest where ethanol plants are close to and have a consistent supply of corn, access to water resources, and have livestock production nearby.

A by-product of ethanol production is distillers grains, which can be fed to livestock either wet or dried. Because the wet distillers grains are perishable and heavy, which adds to transportation costs, they are usually used within a mile radius of an ethanol plant. Distillers grains are more stable and easier to transport when an ethanol producer dries them, however that increases the energy cost for the ethanol producer.

Distillers grains retain many of the nutrients from corn, since only the starch has been removed. Due to the high fiber content most of the distillers grains are fed to beef and dairy cattle, however, they can also be used as poultry and pig feed. In most of the newer ethanol plants, also known as "dry grind" plants, the corn kernels are finely ground into small particles.

The feedstock for advanced ethanol is typically from the non-edible parts of crops such as straw, corn cobs and husks, and also dedicated energy crops. The biodegradable fraction of municipal solid waste is considered to be a promising feedstock. Processing this feedstock requires high-tech facilities, pioneering enzyme and yeast extraction technologies as well as highly skilled people. Ethanol made from cellulosic, waste or residue material has the same chemical characteristic as any other type of ethanol; when used as an alternative fuel, it is commonly known as second-generation ethanol.

The main difference between the two is in the initial treatment of the grain. Enzymes are added to the mash to convert starch to sugar. The mash is cooked, then cooled and transferred to fermenters. Yeast is added and the conversion of sugar to alcohol begins. It is then ready for shipment. The stillage is sent through a centrifuge that separates the solids from the solubles.