A guide to Ethanol

What’s ethanol? Also known as ethyl alcohol, is a fuel made from biomass or other agricultural products such as corn grains, bagasse, and sugar cane, among others. Ethanol is usually used as motor fuel. However, a homogenous mixture of ethanol is rarely found. The most common blends of ethanol fuel are E-85 and E-10, which contain 85 and 10 percent respectively. The production of ethanol also yields bi-products, which can be used by farmers for feedstock.

How is ethanol made? Chemically, ethanol is an alcohol hydrocarbon molecule. The process, with which this is produced, can be described with the following equations:

6 CO2 + 6 H2O + light → C6H12O6 + 6 O2
C6H12O6 → 2 C2H5OH+ 2 CO2 + heat C2H5OH + 3 O2 → 2 CO2 + 3 H2O + heat

Ethanol fuel is produced in plants in a multistep process:

1. The first step in the process is the production and delivery of the biomass primary resource, such as corn or sugar cane.
2. After received, the grains are stored in the plant.
3. Grains are then passed through a mill, which grinds it into powder.
4. The slurry is then creating when mixing this grain powder with water and enzymes.
5. The slurry is then held in liquefaction tanks, which enable the enzymes to break the starch into fermentable sugars.
6. Yeast is then added to the fermentable sugars, and later on, added to fermentable sugars.
7. The resulting solution is then distilled in order to separate the ethanol from solids.
8. The ethanol is then dehydrated in order to reduce its water percentage.
9. Gasoline is then added to the mixture to make it unsuitable for consumption.
10. Grains from the previous distillation process are then separated and sent through dryers so that they can be used as feedstock.
** Process as described by the American coalition for ethanol organization

What is the Impact of Ethanol on the Environment? The use of ethanol as a fuel can have both positive and negative effects on the environment, depending on the magnitude of its use and how efficient it is produced. Ethanol production and usage yields neutral (0) greenhouse gas emissions for it is produced from biomass, which follows a lifecycle that needs CO2 gas and produces oxygen.

All ethanol mixtures in the market have a positive energy balance (the difference between energy used to produce it and the fuel’s energy output per unit) although some are more efficient than others. The easier it is to break down the sugars composing the primary resource from which the ethanol will be made, the more efficient and more positive its energy balance. Therefore sugarcane-based ethanol has a much better energy balance than corn-based ethanol.

Even though the use of ethanol does not emit CO2 through its lifecycle, its production does possess another type of environmental problems. In countries where agriculture is not as industrialized as the United States, ethanol crops are grown in large extensions of land and this yields to deforestation. Deforestation in Brazil and other parts of the world due to ethanol crop growth is an increasing problem.

Does ethanol produce real economic value? Increasing climate change and decreasing petroleum reserves yielding to higher gasoline prices have led many countries in the world to pursue fuel alternatives. Biofuel production from corn has been heavily supported through subsidies in the United States in recent years, while other countries already have a very well established biofuel industry. Brazil has a very strong ethanol industry, which powers the country’s highways and the EU has also actively pursued a more green fuel blend through policy. Ethanol production is expected to grow worldwide because of its lower price than gasoline and because of its ease of distribution. As automobile companies adapt to a more green fuel blend world, more cars will be available. Ethanol flex-fuel cars will also continue to get better as the fuel becomes more popular. In fact, some NASCAR drivers already use ethanol-powered cars, proving how good the fuel could be and how popular it can become.


Please follow up with any feedback or doubts about this article, thanks.

~Roberto Baldizon