Petrobras Mexilhao platform jacket launched to the sea

24 Nov 2009

Petrobras - The first stage of the Mexilhão Platform (PMXL-1) installation was carried out this weekend. Late November 22nd, the jacket - the steel structure that serves as the base for the platform and is attached to the bottom of the sea - was launched to sea in the Santos Basin. The operation was carried out nearly 140 kilometers off the coast of Caraguatatuba (state of São Paulo), where the PMXL-1 will go on stream in 2010. Mexilhão will be Brazil’s biggest fixed gas platform, capable of producing up to 15 million cubic meters of gas per day - equivalent to half of the Brazil-Bolivia pipeline’s capacity.

The jacket is a steel structure with a square base measuring 70m x 70 m and an square top measuring 40m x 40m. It is built of tubes that weigh a total of 11,300 tons. Standing 182 meters tall, after installed, its top will be 10 meters above the water line. The platform’s total height, from the seabed to the tip of its modules will be 227 meters, equivalent to a 75-story building. Both the jacket and the modules were built in Niterói (state of Rio de Janeiro) in agreement with the minimum 70% national content requirement. Together, the two modules that will be placed on the jacket weigh in excess of 12,000 tons. The modules house the gas processing and utility facilities, including its 7-MW power generation capacity fueled by three gas-powered turbogenerators, in addition to lodging for up to 100 people, and a heliport.

The jacket was launched to the sea by the Saipem 600 barge. The barge has ballast control devices, and launched the jacket into the water by means of tracks and by sinking its stern. Flotation tanks control the jacket in order for it to remain in the vertical position in the water.

The modules are slated to be transported to the location and installed on the jacket late this year. After installed and welded, the modules will be interconnected and the PMXL-1 prepared to be connected to the wells and to the gas pipeline that will transport the gas from the Mexilhão field to Caraguatatuba, where the Monteiro Lobato Gas Treatment Unit is being built and to which the gas received from the Uruguá and Tambaú fields, in Rio de Janeiro, and from the Tupi Pilot project, in the Santos Basin’s Pre-Salt Pole will also flow.

The Saipem 7000 crane barge will position the jacket on its proper location and attach it to the bottom of the sea using 116-meter-long piles that weigh 400 tons each. This operation is expected to be completed by the end of the month.

The modules are slated to be transported to the location and installed on the jacket late this year. After installed and welded, the modules will be interconnected and the PMXL-1 prepared to be connected to the wells and to the gas pipeline that will transport the gas from the Mexilhão field to Caraguatatuba, where the Monteiro Lobato Gas Treatment Unit is being built and to which the gas received from the Uruguá and Tambaú fields, in Rio de Janeiro, and from the Tupi Pilot project, in the Santos Basin’s Pre-Salt Pole will also flow.