The Troll A is an offshore natural gas platform, the largest offshore platform ever built: it rises about 170 meters (558 feet) above water level, weighs 656,000 tonnes and its total height is 472 meters (1,549 feet).
natural gas extraction, natural gas, gas field, deposit, extraction, offshore platform, oil rig, torch, condensation, sea, petroleum, mineral resource, tanker, technology, geography
- The Troll oil and gas field is situated in the North Sea, off the west coast of Norway, approximately 1,400 meters (4,593 feet) below sea level and 1.1 kilometers (0.7 miles) below the sea floor. It holds approx. 40% of the natural gas reserves of Norway, whose extraction is expected to last till 2080.
- The posts have one-meter (3.281-feet) thick walls and consist of one single piece.
- They are pressed 35 meters (115 feet) deep into the socle, fixing the posts. They serve as suction pads.
Troll A (472 m or 1,549 ft)
Empire State Building (381 m or 1,250 ft)
- The liquefied natural gas is cooled to -170 °C (-274 °F or 103 Kelvin). It is stored and transported at this temperature.
The condensation of natural gas. When gasses are compressed, heat is generated. Heat can be reduced through cooling. Gas turns into liquid when cooling, and a strong reduction in volume is induced. During liquefaction, the volume of natural gas amounts to six hundredths of the starting volume and is cooled down to -170 °C (-274 °F), i.e. 103 K. In reality, it is not the piston which induces the liquefaction of natural gas, as seen in the animation. Liquefaction is induced by compressors, in which compression takes place as result of the action of rotary vane wheels.
The Troll oil and gas field is situated in the North Sea, on the west coast of Norway, approximately 1,400 meters (4,593 feet) below sea level. It holds approximately 40% of the natural gas reserves of Norway, whose extraction at Troll A is expected to last till 2080. Trolls B and C are oil platforms.
Troll A is the largest offshore platform ever built: it rises about 170 meters (558 feet) above water level, weighs 656,000 tonnes and is 472 meters (1,549 feet) high. The four reinforced concrete posts end up in suction cylinders which are pressed 35 meters (115 feet) deep into the socle, fixing the posts. Therefore the suction cylinders serve as washers.
The construction started in 1991. In 1996, it took 7 days to haul the platform a distance of 200 kilometers (124 miles) to its present location. 10 ships were required for the operation. The Troll is the largest construction ever shifted by humans on the earth's surface and thus one of the top engineering achievements.
During the first ten years, high pressure was used to bring the gas to the surface. However, after the pressure decreased, the extraction has been carried out by huge fans which move the gas at approx. 3,000 km/h (1,864 mph) through the pipes.
The gas is then processed at a plant in Kollsnes on the Norwegian coast. Here, gas compressors liquefy and compress the gas, which is eventually transported to the users by pipelines and tankers.
Beside other uses, natural gas is widely utilized for heating or for producingelectricity in power plants. It is one of the most important sources of energy. Therefore, economically speaking, its efficient extraction is extremely important.