Off the coast of Tierra del Fuego is Argentina’s largest offshore production project, in which Wintershall Energía holds a 37.5 percent interest. Carina and Aries are the two deposits from which we and our partners (Total and PanAmerican Energy) produce natural gas. Discovered in 1983, Carina is located around 80 kilometers off the coast. At a depth of around 1,000 meters below the seabed (water depth is between 80 to 100 meters), oil and gas are found in an area of 890 square kilometers. Aries, which is around 30 kilometers off the coast, was discovered in 1981. This field covers an area of four by twelve kilometers under the seabed (water depth is between 60 to 80 meters). The gas in the Aries field is found at a depth of around 1,600 meters and is richer in condensate than the gas found in Carina. We plan on producing a total of around 56 billion cubic meters of natural gas, 3.4 million tonnes of condensate, and 2.4 million tonnes of liquefied petroleum gas (LPG) from the two gas fields by 2027.
We use production platforms to recover gas from the offshore reservoirs in Argentina. The steel constructs consist of two parts, the jackets and the decks. The jackets, which are firmly anchored to the seabed, carry the weight of the platforms. They were made in a shipyard in Louisiana in 2003 and then shipped to the deposits. Both as tall as high-rise buildings, the Carina jacket is 80 meters tall and 15 meters wide and the Aries jacket is 76 meters tall and 15 meters wide. The decks of the production platforms sit on top of the jackets and wereB uilt in the harbor of Veracruz in Mexico. In 2004 they were shipped to the coast off Tierra del Fuego.. Both platforms are unstaffed, because gas, condensate, and water are only separated after arriving at the Rio Cullen plant.
Steel structures on the seabed also contribute in producing gas. A 100-kilometer-long pipeline network is needed to transport the resource to the mainland. This may sounds easy to manage, however the low underwater temperatures alone prove technologically challenging. The temperature on the seabed is around two degrees, which means that wet gas in the pipelines could form hydrates and clog up the pipeline. To prevent this from happening, we add monoethylene glycol (MEG) to the gas to significantly lower the freezing point. On the mainland, the “antifreeze” is later recovered.
In addition to low temperatures, the pipeline also has to withstand the enormous pressure of the water column. For this reason, the pipeline of the Carina field (80 kilometers long) has 15-millimeter thick walls, so that it can withstand as much as 96.5 bar. Heavy weights had to be shifted to make this possible with each pipeline element measuring 60 centimeters in diameter, twelve meters in length, and weighing twelve tonnes. The Aries pipeline (21 kilometers long) is a bit slimmer with its diameter of 45 centimeters. Both pipelines have a coating to protect them from being corroded by the aggressive sea water.
In Rio Cullen, the consortium’s processing plants separate the elements of gas, condensate, and water. The plants are designed for a maximum production volume of approximately 14 million cubic meters per day. From Rio Cullen, the gas is piped to the Cañadón Alfa natural gas processing plant. From there, it is sent through the San Martin pipeline, and after travelling more than 3,000 kilometers the offshore gas can be used to provide a secure energy source to major cities and industrial centers in Argentina.