Japan Mines 'Flammable Ice'

Looks like China and India aren't the only ones trying to mine methane hydrates.

Japan is joining the U.S. and Canada in test drilling for methane even as scientists express concerns about any uncontrolled release of the frozen chemical.

Japanese engineers have found enough ``flammable ice'' to meet its gas use demands for 14 years. Billions of tons of methane hydrate, frozen chunks of chemical-laced water buried in sediment some 3,000 feet under the Pacific Ocean floor, may help Japan win energy independence from the Middle East and Indonesia. Trapped within sheets of ice up to 500 meters (1,640 feet) thick is an estimated 40 trillion cubic feet of crystalline methane encased in an ocean trench called the Nankai Trough, 30 miles (50 kilometers) off the coast of the main Honshu Island.

If successful, the gas drilling project could help Japan reduce a liquefied natural gas import bill that last year was 2.66 trillion yen ($23.3 billion). The country's LNG imports totaled 62.2 million metric tons, equivalent to 3.03 trillion cubic feet, according to the Ministry of Finance's trade report.

A first round of drilling was completed in April by Jogmec and the Canadian government and a second set of tests are scheduled for early 2008. The two governments won't disclose results due to a confidentiality agreement, Jogmec's Yokoi says.

The most efficient method has proved ``depressurizing,'' which requires deep bore holes being drilled into the ice sheets. Pressure within the chamber is reduced by a pump, causing gaseous methane to separate from the water and ascend to the well head.

Japan's government is promising rigorous environmental controls with gas-leakage detectors and monitoring systems in place before the scheduled test drilling in as early as 2009. The trade ministry is targeting 2016 to start production, corresponding with the scheduled completion of the 16-year government-led test project.

via Bloomberg