February 2, 2013

Regarding Prospects for Methane Hydrates Production

S. Dyachenko

At the beginning of January 2013 in Japan on the shelf of the Pacific Ocean near the island of Honshu (70 km. South of Nagoya) there started experimental production of methane hydrates. This was preceded by studies and exploratory drilling in the coastal area of the Pacific that the Japanese services carried out in 1996. At present, methane hydrate deposits near the Japanese coast are estimated at 11 trillion cubic meters.

Now the Japanese are planning to try a full-scale production of methane hydrate in experimental mode with the subsequent release of methane from it. If these plans are successfully realized, in 2018, according to the plan, full-scale exploitation of "Nagoya" resource will begin.

Methane hydrate is a crystalline substance composed of water and methane molecules. This compound is stable at low temperatures and high pressure (such as a temperature of 0 ° C and a pressure of about 25 bar, which takes place in the ocean at a depth of 250 m, or at atmospheric pressure and temperature of - 80 ° C) and occurs mostly under permafrost (2 of deposits) or in the depths of the seas and oceans at great depths (98of deposits).

At raising the temperature or lowering pressure, the compound decomposes into water and methane, and in the process from 1 cubic meter at atmospheric pressure, 164 cubic meters of methane can be got.

First methane hydrate was got in 1888, and in 1970 specialists began studying its potential as of an energy carrier. Today the world's methane hydrate deposits are estimated at 250-300 trillion cubic meters, while by their energy value they excess 2 times the world's deposits of oil, gas and coal.

 Card established (yellow dots) and expected (red dots) deposits of methane hydrate in shelf waters of the world ocean
Card established (yellow dots) and expected (red dots) deposits of methane hydrate in shelf waters of the world ocean

There are currently 220 zones with deposits of methane hydrates in shelf areas of seas and oceans. Active researches for technologies of their production are being carried out in the USA, Canada and Japan. But so far none of the proposed technologies has given results which would allow to get the cost of recovered methane hydrates comparable with the cost of other energy carriers, especially with the cost of natural gas. There are environmental and security problems too. This is due mainly to the fact that methane is a potent greenhouse gas and its leaking in the process of extraction may worsen the situation of global warming. Explosive properties of this compound should not be ignored either.

Now experimental extraction of methane hydrates is being carried out in the Arctic areas of the U.S. and Canada. For example, in 2002, an international research consortium involving academic organizations in the USA, Canada and Japan, started experimental production of methane from onshore Mallik resource in the Canadian Arctic in the mouth of the Mc Kenzie River. On the 2nd of May, 2012 it was announced about the successful experiments with methane extraction at "Ihnik Sikumi number 1" northern slope of Alaska.

There is a growing interest in the subject in Europe too, in particular - in Germany.

Significant deposits of methane hydrates have been found in the Black Sea. Their studies were conducted in 1988-1989. The deposits found by Russian, Ukrainian and Bulgarian scientists under the bottom layer at the depth of 300-1000 m, are estimated at 45-75 trillion cubic meters. In 1993, Ukraine adopted the program "Gas Hydrates of the Black Sea", within the framework of which several scientific expeditions were arranged, seismic studies were carried out. But further financing of this project stopped.

Today in Ukraine there is a technology of extraction of methane hydrates, offered by local researchers of Odessa Academy of Refrigeration. But for its completion 100-200 thousand US dollars are needed, which so far can’t be found. And a full-scale production of methane hydrate based on this technology, will need investments of 480 million US dollars.

Unfortunately, the Ukrainian state institutions responsible for the development of fuel and energy complex do not pay proper attention to the problem of methane hydrates, which is particularly evidenced by its absence in the project of the new energy strategy.