Voith Vorecons Transport 39 Million Cubic Meters of Gas Every Day
06 June 2008
Whenever worldwide oil and gas reserves are being discussed, media reports mainly refer to dwindling resources. This does not apply to Brazil: the state-owned oil and gas company Petrobras has recently discovered significant oil and gas deposits in the world’s fifth largest country. There are no less than 15 oil fields, which have turned Brazil into a net exporter of crude oil. For the pipeline transport of extractable natural gas to the processing plant in Caraguatatuba, Voith Turbo will deliver five Vorecons in spring 2008. They will enter service in the second half of 2009.
Huge amounts of oil and gas are stored under the seabed on the southeastern coast of Brazil, for example in the Campos basin outside Rio de Janeiro, in the Santos basin outside São Paulo, or in the Espirito basin. Approximately 80% of the embedded resources consist of oil; this is why Petrobras has already ordered ten new production platforms. In order to reduce the dependency on imported natural gas, Petrobras has set up Plangas, a strategic plan for increasing the extraction volume for the Brazilian market by 39 million cubic meters per day until 2010.
Among the current projects of Petrobras are the production, transport and treatment of oil and gas from the Santos basin. From the new Mexilhão oil platform, oil and gas from at least six wells are to be extracted and forwarded to the new UTGCA gas processing plant in Caraguatatuba. The coastal town is strategically positioned between Brazil’s two largest consumer centers - 150km away from Sao Paulo and 250km away from the state of Rio de Janeiro. The six wells are situated at depths varying from 320m to 550m. Their horizontal spread is approximately one kilometer, and they are about six kilometers deep. The reserves of the Mexilhão gas field are estimated to be some 93 billion cubic meters of natural gas.
In the first stage, the plant in Caraguatatuba will be able to treat approximately 15 million cubic meters per day. The natural gas is forwarded under pressure to the town limits of Taubaté, where it is connected with the Campinas-Rio gas pipeline by a 100km conduit. For processing the gas and subsequently releasing it into the pipelines, Voith Turbo delivers five RWC 12-11 F 7 Vorecons. This Vorecon type consists of a hydrodynamic torque converter, a fixed planetary gear and a revolving planetary gear. The RWC also includes a hydrodynamic variable-speed coupling with a clutch. Each of the five Vorecons is rated at 7.8MW.
The customer decided in favor of the Vorecon, as the compressor is driven by an electric motor. In this combination, the mechanical solution offers significant advantages over a frequency inverter and is also more economical than a gas turbine. The application involves two smaller Vorecons - the largest is rated at 33MW - but the specifications are demanding and correspond to those of offshore platforms. After all, the conditions along the coast are very similar and require robust technology. The Vorecon allows high efficiencies across wide speed ranges and has a reliability rate of 99.97%.
