Japan completes first ever gas extraction from seabed

Japan’s state-run company, Japan Oil, Gas and Metals National (JOGMEC), has become the first company in the world to extract gas from offshore methane hydrate deposits, using depressurisation technology.

The company said the gas was extracted from deposits of methane hydrate, which is a frozen gas, also known as "flammable ice", near the country’s central coast.

The trade ministry of Japan announced that production tests will be carried out for up to two weeks, which will be followed by tests on how much gas has been produced, reported Reuters.

The country, which has been importing most of its energy to meet domestic demand since 2001, has invested several hundred million dollars to develop technology to tap methane hydrate reserves off its coast.

According to a Japanese study, it is estimated that about 40 trillion cubic feet (1.1 trillion cubic metres) of methane hydrates can be found in the eastern Nankai Trough, off the country’s Pacific coast. Methane hydrate is developed from a mixture of methane and water deploying certain pressure and conditions.

Since methane is an important component of natural gas, governments of several countries, including Canada, the US, Norway and China, are exploring possibilities to harness hydrate deposits as an alternate energy form.

In 2008, the company used depressurisation for the first time to produce methane gas, for a continuous six-day period, from hydrate reserves held deep in permafrost in Canada.

Japan relies on the depressurisation technology to transform methane hydrate to methane gas as a more effective process than using the hot water circulation method.

In February and March 2012, JOGMEC conducted preparatory works, including drilling a production well and two monitoring wells.

The company said the first offshore production test is planned for the next two years, which would be purely an experimental operation, rather than a commercial one.

The plan is to advance with the second offshore production test, scheduled in phase two, and develop the technological platform for future commercial production in phase three, which is scheduled from 2016 until 2018.