By an OGJ Online Correspondent
RIO DE JANEIRO, Mar. 16Petroleo Brasileiro SA (Petrobras) officials Friday said the heavily damaged P-36 platform was slowly sinking Friday and that the estimated production loss is $50 million/month.
Two explosions and a resulting fire racked the 40-story platform Thursday, killing one person, seriously burning one, and leaving nine people missing. Petrobras officials Friday said the missing are presumed dead.
Cause of the explosions was unknown Friday. Petrobras executives said a task force had been formed to investigate the accident.
The world's biggest platform of its kind, the P-36 was producing in more than 1,300 m of water in giant Roncador field in the Campos basin, 120 km off Rio de Janeiro. (OGJ, Sep. 20, 1999, p. 33). The platform had been producing 84,000 b/d and 1.3 million cu m/d of gas.
Divers periodically checked the platform Friday to evaluate its condition. The platform was tilted Friday at about 25� to the horizon, Petrobras executives said.
Ronnie Vaz Moreira, Petrobras finance director, said the $50 million/month in lost production represents 2% of the company's monthly revenues of $2.3 billion. The platform itself was insured for $500 million. Crude from the platform was selling at $20.50/bbl.
The P-36 had been projected to produce 90,000 b/d of crude by the end of the year and to peak at its capacity of 180,000 b/d by 2004.
The accident happened as Petrobras was negotiating its insurance renewal with international insurance companies for physical damages worth $29.9 billion.
With a deadline of Mar. 31, the insurance companies initially required a premium payment of $12 million.
If the platform is lost, Brazil might have to import an additional $475 million of crude this year, Petrobras executives estimated.
The loss of the P-36 would force Petrobras to halt production in Roncador field and install an alternative, smaller production system.
Carlos Tadeu, Petrobras' southern region E&P director, said it will take up to 36 months to have another platform built that would replace the size of the P-36.
Tadeu said, "The alternative would be to install a small-size production system with small ships linking the Roncador wells. But, evidently the production capacity will be smaller."
The semi was known as the Spirit of Columbus during its drilling rig days.
The P-36 was built in 1994 by the Italian company Ficantieri. Petrobras hired Petromec, a subsidiary of Brazilian company Maritima Construcoes Navai to convert the rig into a submersible production platform for $354 million. The platform was delivered in 1999 and began to produce oil and gas in May 2000.
The original drilling facilities and most of the production equipment were stripped out. The original utility systems remained, but these required overhauls and some upgrades.
In order to accommodate larger production facilities, a new, 13-m long cantilever extension spanning all of the aft main deck was added. To comply with new stability and buoyancy criteria, modifications to the columns, pontoons, and central caisson were required, entailing expansion of blisters and addition of buoyancy boxes.
In addition, a spider deck was created 5 m below the lowest existing deck (with a tank top elevation of 35 m), enabling pull-in operations to be craned out, Petrobras officials said at the time of the conversion.
The modifications added 2,400 tons of steel plus about 5,300 tons of piping and equipment to the unit.
Ninety steel catenary risers (SCRs), installed in 1,360 m of water and weighing more than a combined 5,200 tons, were be hung off the platform.
The P-36 has a displacement of 56,503 tons, weighs 32,400 dwt, has 60 rooms, a gym, a restaurant, and a hospital.
Roncador is a 132 sq km area that holds oil reserves estimated at 3 billion boe. It has the world's deepest offshore producing well-producing 20,000 b/d of crude oil-in 1,853 m of water. Discovered in October 1996 with the 1-RJS-436 wildcat, Roncador lies in 1,500-2,000 m of water northeast of Albacora and Frade fields.