Shipping ethanol: Key facts

Ethyl alcohol: What is it?

Ethyl alcohol, also known as ethanol, is the proper name for grain alcohol spirits.

In academic organic chemistry, this substance is also known as ethyl hydroxide, which is produced by the fermentation of sugar. This is one of the oldest chemical processes known to humanity.

Since the mid-twentieth century, ethanol has been produced for industrial use as a by-product of petroleum refining. It has since become a partial replacement fuel for gasoline-powered engines. Since most of the ethanol consumed in automotive engines today is derived from plant matter, modern day gasoline is a partial bio-fuel.  

Worldwide approach

The world's production of ethanol for automotive fuel tripled between 2000 and 2007 from 13 million tonnes per year to more than 41 million tonnes per year.

International trade in ethanol and bio-diesel has been limited so far, at about 2.5 million tonnes per year between 2006 and 2007, however, this is expected to grow rapidly. Brazil, for example, exported a record high of about four million tonnes of ethanol in 2008.  Brazil is the largest exporter of ethanol while the US is the largest importer. The US also exports a small quantity of ethanol.

Shipping of ethanol

Ethanol is shipped and stored at an ambient temperature and atmospheric pressure. Like gasoline and diesel fuel, it is never heated prior to being pumped through a hose or pipeline. When shipping ethanol by tank ships, the following points are important:

• The level of concern among transportation workers handling ethanol is midway between gasoline and diesel fuel. Ethanol is a Grade C flammable liquid, with a closed cup (sealed lid) flash point of 12.8C, meaning it can be expected to be above its flashpoint in warm weather. Gasoline is always above its closed cup flashpoint of 3.3C, but automotive diesel fuel is almost always transported and stored below its 51.6C closed flashpoint;
• Ethanol, like other alcohols, is somewhat corrosive; however there is little concern for the structure of an ethanol-carrying barge for the structure of an ethanol or its pumps and piping because the tanks are inspected (for certification) as it is wildly corrosive;
• With regard to ship stability and seaworthiness, it is physically impossible to overload a ship or a barge. This is simply because its specific gravity is lower than fresh water;
• There is a great cause of concern for flammable vapours as ethanol is of a wide flammable range. Since ethanol is heavier than air, its vapour spreads out downwind and downhill, hugging the deck.

Heath concerns  

Even exposure limits of 1,000 parts per million (ppm) for a short term may cause headaches and/or eye irritation. Other side effects are dizziness and double vision.

Symptoms may be alleviated by exposure to fresh air.

Future perspective  

Ethanol usage as a bio fuel is increasing on a worldwide basis. More and more ethanol-carrying tankers are employed and inspected with qualified technical personnel in charge for operation and inspection.

Said Lamey Tawfik