Undated handout photo of a frozen gas hydrate being lit with a match. Hydrates occur in vast quantities under the oceans and permafrost
They came up with $48 million -- with $3 million from Canada -- for an epic experiment in the Northwest Territories that has generated tantalizing evidence, to be detailed in Tokyo this week, that frozen gas hydrates may live up to their billing as a plentiful new energy source.
The Canadian and Japanese team will describe how they got the hydrates to release gas, like bubbles out of champagne. In a world first, the team got a production well to generate a steady flow of gas for six days, fuelling a flame in the Arctic darkness.
"The message is quite clear, you can produce gas hydrates using conventional techniques," says Scott Dallimore, a senior scientist at Natural Resources Canada, who co-led the project in the Mackenzie Delta. Over two winters the researchers drilled down more than a kilometre into a 150-metre-thick layer on the edge of the Beaufort Sea at Mallik -- the most concentrated known deposit of the frozen fuel in the world.
"It's a landmark, no doubt about it," says Ray Boswell, technical manager of the U.S. government's gas hydrate program. Boswell will be taking close notes Tuesday as Dallimore and his Japanese colleagues describe how the well and hydrates responded as the gas was freed.
Previous experiments have produced gas from hydrates for a few hours. Mallik's steady, sustained flow for six days "is very good news," says Boswell, who is optimistic gas hydrates may one day heat homes and fuel vehicles.
Hydrates occur in vast quantities under the oceans and permafrost, where tremendous pressure traps gas in tiny cages or crystals made of water molecules. When brought to the surface the cages melt, releasing methane gas that will burn if lit with a match, generating "fiery ice" -- a potential energy source that has long intrigued researchers.
The volatile energy source has traditionally been a nuisance for drilling operations and folks poking around deep water. A decade ago, B.C. fishermen were startled when they dredged up a huge chunk of icebound hydrates off the coast of Vancouver Island. It fizzed like a giant Bromo-Seltzer as it reached the surface and released flammable methane gas.
There are also concerns about its environmental impacts and the possibility of "burps of death" as the planet warms -- the fear being some hydrate deposits might melt releasing huge amounts of methane -- a potent greenhouse gas -- that could then speed up global warming.
On the upside, hydrates are said to contain more energy than all other fossil fuels combined, and are much cleaner than oil and coal.
Global estimates "range from merely jaw-dropping to the truly staggering," according to the U.S. Department of Energy. Canada is believed to have enough hydrates along its coasts to meet the country's energy needs for a couple of hundred years.
Hydrates contain methane, also known as natural gas, which produces 40 per cent less carbon dioxide than oil or coal when burned. Some analysts have suggested the "clean" hydrate gas could significantly reduce global emissions if used to help wean the world off dirtier fossil fuels. There is also a possibility, to be tested in Alaska this winter, that carbon dioxide can be pumped and stored underground as part of a novel process to liberate the gas from the ice.
Tapping into gas hydrates for fuel is still years, if not decades, away because "the game-changing, paradigm-shifting" reserves are under the oceans and are very hard to get at, says Boswell.
Still, Japan, India, Korea and the U.S. are all sizing up their marine hydrates. Japan's national gas hydrate program is the most ambitious and calls for offshore production testing to begin in the deepsea Nankai Trough in 2012.
For their test runs the Japanese turned to Canada's Arctic, where hydrates were first encountered 40 years ago during oil and gas exploration in the Mackenzie Delta.
The Japanese approached Natural Resources Canada scientists in the late 1990s about collaboration and in 1998 a Canadian-Japanese team cored into the Mallik hydrates for the first time, bringing chucks of frothy, sandy material to the surface.
Working with U.S., Indian and German scientists in 2002, the team tried to melt gas out of hydrates with hot water without success.
Japanese and Canadian scientists turned to conventional oil-and gas-extraction techniques, which involve reducing pressure on deposits, in 2007 working with Inuvik's Aurora College on full-scale production tests.
The crew hauled a drill rig north to Inuvik, then over the 200-kilometre ice road they built up to Mallik, where the research could only be done in winter because the low-lying delta is so wet and ecologically sensitive in summer.
With temperatures at times dipping below -60 C with the wind chill, they threaded pipe, containing gauges and monitors, more than 1,300 metres down through the hydrate layer. They then created holes in the pipe to reduce the pressure holding the methane in the icy cages.
By March 2008 they finally got gas to bubble up the well and it flowed steadily for six days.
David Boerner, acting assistant deputy minister at Natural Resources, says the Mallik project has been a major step forward and hopes to get a sense this week of the type of projects and problems that need to be addressed in the next phase of research.
Boswell and Dallimore say longer production tests on land are needed to see if hydrates can generate gas for months and years in a safe and environmentally sound manner.
Dallimore says long-term production tests, ideally at several locations around the world, are a logical next step. "My hope is that Canada will find a way to continue to play a leading role," says Dallimore.
No comments:
Post a Comment