On and offshore gas hydrates contain huge amounts of energy locked up in a frozen matrix of water and methane.
Poorly understood, these phenomena killed two drillers in the early drilling in the Mackenzie Delta.
Worldwide hydrate reserves are estimated to contain more carbon than all the fossil fuels currently in use.
Visually, they look very similar to ice, or dry ice.
The methane locked in the ice is often a result of biological activity in a marine environment trapped through pressure and cold.
These hydrates are attracting attention because they hold huge volumes of gas trapped in the ice, which could feed future energy needs.
Conservative estimates of energy trapped in these hydrates is 10 times the current energy consumption, and will extend the world’s energy reserves by many years.
Surveys show that 17 per cent of 145 onshore wells in the Mackenzie Delta show evidence of gas hydrates.
Estimated reserves of gas trapped in the hydrates is 16 trillion cubic meters in the Delta region alone.
In a marine environment, the hydrates are a renewable resource, re-forming as methane becomes trapped by the water molecules.
In Canada, a joint venture between the Japanese and Canadian governments and private industry is funding an ongoing project in the Mackenzie Delta called Mallik.
This hydrate field was discovered by Imperial Oil in 1971-72 drilling season.
In 2002, a 1,200-metre drilling program was proposed and completed along with two scientific wells to study the hydrates.
The results of the drilling indicated the Mallik gas hydrate field to be one of the most concentrated in the world.
At a cost of more than $14 million and utilizing the Inuvik Research Centre, the project helped expand knowledge of this poorly understood proposed energy source.
Though the work being done in the 2007-‘08 field season is in the NWT, the gas hydrates are all along the Arctic coast, so the Yukon also is expected to contain substantial reserves.
The Mackenzie Delta is an expensive area of the world to work in, but because Ottawa has partnered in this JV, the Delta area benefits from the project.
With an overall budget of more than $20 million, the region will benefit from a stronger economy and knowledge of new technology.
Operations in the Delta region use cold-weather construction methods to preserve the integrity of the tundra.
This means roads are built on Mackenzie River channels and lease pads are constructed with snow and arctic super glue or, as it is more commonly known, water.
River road ice is first profiled with ground penetrating radar to map the thickest ice and to determine if the channel will carry the road construction equipment.
Once a route has been mapped, the road-building company clears the snow to a width of 30 metres. Thin sections of ice are watered to thicken the section to load bearing weight.
Once the road is cleared and profiled a sled camp is mobilized for the pad construction crew.
This camp is the usual winter ATCO units on sleds moved with heavy equipment.
This sled camp is located on shore fast ice and is a self-contained unit.
The crew building the lease pad operates out of this camp until the lease is finished.
The crew then moves into the rig camp, which has been assembled on the lease pad. The sled camp is then de-mobilized back to the base in Tuktoyaktuk.
The sled camp location is then inspected by the onsite environmental monitor and signed off as clean.
All operations then move to lease.
Mullen Trucking brings in its bed trucks, or “sows,” which are used to move unitized units around the lease.
Rig Matting (2×8 lumber boxed with metal) is placed on the ice surface of the lease with tarps underneath to capture any spills.
These mats both protect and insulate the ice from the equipment placed upon them.
Once the mats are in place the sections for the service rig are placed upon them — boilers and light plants along with all the mud tanks for the operation.
All the assorted piping is laid out, insulated and enclosed.
Once the piping and lines are in place they are all pressure tested to ensure there are no leaks.
At the same time the Blow Out Preventor is tested to ensure it functions correctly.
Meanwhile, the well-testing crew from Schlumberger, the largest oil service company in the world, is rigging in all their testing equipment and pipelines.
Schlumberger brings specialized equipment to measure flow rates and gas types.
As a joint-venture partner in the Mallik project the company brought proprietary equipment and methods to the project.
As with any project in extreme weather there have been problems but they have been solved and methods put in place to deal with the cold.
Unexpected engineering difficulties were solved and the project is nearing the point where the Mallik well will produce gas.
Currently the gas hydrates are under a pressure of 1,100 metres of static head of a brine solution (potassium chloride and water in a five per cent solution) to keep the gas/water mix stable.
To have the well produce gas the plan is to depressurize the well to bring the pressure at the hydrate level to one atmosphere (surface air pressure).
This will enable the gas to free itself from the water “cage” that has formed around the gas molecule.
The ice will move across the phase barrier to the liquid state so a pumping system has been installed to lift the water out of the well.
A down-hole heater adds energy to the system to keep the hydrate from re-forming in the pipe stem.
This water will contain hydrocarbon remnants and will be injected back into the formation through an adjoining well.
The gas hydrates are formed in a matrix of marine sands and pebbles.
Once the gas is removed, this matrix loses stability and will flow to the well.
To prevent the plugging of the well casing, sand screens were installed to remove the influx of material into the well.
The project had an absolute cutoff date of April 10th to have all material and equipment staged off the lease.
This mandated the testing process could only last several days.
Though the testing phase of the project was limited the project was considered a success.
Gas was produced from the hydrate level of the well and the site was capped and abandoned according to the permit.
The target of this project was to produce gas from the hydrate systems, and it did.
The next step is to commercialize the project to see if cost-effective method of recovery can be established.
The Japanese plan to have gas hydrate production plants in production by 2012, or sooner.
The primary reason the Japanese are funding this research is to develop their own energy resources of which marine gas hydrates play a pivotal role.
If hydrate gas production is commercialized successfully, Japan will be able to reduce their dependence on Middle East production while at the same time building a home-grown energy product.
Currently the Mackenzie gas pipeline project appears to be on hold again.
One of the many difficulties under the proposed plan is the proposed development in the Sautu area of the NWT.
If the commercialization of gas hydrates production is successful this will add immense reserves to a gas pipeline.
Another technology produced from the understanding of gas hydrates is the ability to transport very dense volumes of gas in hydrate form.
This would remove the need to actually build a pipeline down the Mackenzie Valley.
The current infrastructure of the Dempster Highway would carry the gas production from the Delta to points south.
The ‘07-‘08 field season on the Mallik project answered many questions about gas hydrates while generating many new questions.
When and if the commercialization will happen is anyone’s guess.
With the continued rise of hydrocarbon prices, what was once un-economic has become potentially profitable.
However, there are massive reserves of conventional gas that demonstrate a stronger profit potential, so don’t look to see this gas hydrate methodology going into production soon in North America.
But in Japan, the economics and politics are much different and the world can expect to see production there in the next decade.
Mark Prins is a Whitehorse-based writer.