* Officials don’t know if chamber will corral leak
* BP breaking new technological ground
By Kristen Hays
HOUSTON, May 5 (Reuters) - BP Plc (BP.L) officials said on Wednesday that they still don’t know if a 98-ton steel “containment chamber” that shipped out to the site of a massive undersea oil leak in the U.S. Gulf of Mexico will stem the flow as hoped.
Television broadcast dramatic images of the huge white structure, loaded onto an ocean-going barge, heading for the site of the leak at the former Deepwater Horizon oil rig -- some 50 miles (80 km) off the Louisiana coast and 5,000 feet (1,500 metres) under the surface of the ocean.
The science involved in the company’s most promising shot so far to contain the leak within a few days has never been done a mile beneath the ocean’s surface, said Bob Fryar, senior vice president of Angola for BP.
“It is important to know that this is new technology,” Fryar told reporters in a briefing.
He declined to rate the chances of whether the chamber would corral oil at the larger of two remaining leak sites and channel it to a pipe leading to a drillship above, as planned.
“This has never been done before. You typically put odds on something that has been done before,” he said.
Fryar and David Clarkson, BP’s vice president for project execution, provided details on the frontier operation.
Following are some of the salient facts:
* Once shipped to the site of the main leak, the chamber will be lowered by cable to the site of the leak. Once at the seafloor, underwater robots will place it on top of the leak. The chamber, 40 feet tall, 24 feet wide and 14 feet deep, has steel shelf-like “flaps” on the side to ensure it doesn’t sink more than 15 feet into the mud, which should leave sufficient space to collect the oil.
* The funnel-like top of the chamber will be connected to a drill pipe inside a larger pipe, known as a riser. That mechanism will then be connected to Transocean’s Discoverer Enterprise drillship.
* The dual-pipe mechanism is necessary to allow warm water and a chemical, methanol, to be pumped into the space between the drill pipe and larger pipe. Cold temperatures and high pressures a mile beneath the water’s surface can allow natural gas and water to turn ice- or sludge-like in the larger pipe and stop the flow, Clarkson said. The leaking oil is “very gassy,” with 3,000 cubic feet of gas in each barrel of oil.
* When the fluids reach the drillship, they will go to a closed processing system designed for normal well testing. There, the oil, gas and water will be separated. The oil will be stored in a tank that can hold up to 128,000 barrels of oil; the gas will be flared; and the water will be dumped back into the sea.
* The larger leak is estimated to be releasing about 85 percent of the gushing oil, Fryar said. A second leak is from a bent pipe connected to a blowout preventer at the seabed that failed, leading to the explosion. A second containment chamber is being built at Wild Well Control in Port Fourchon, Louisiana, to place atop the second leak.
* The oil collected aboard the drillship can be later offloaded onto a standby vessel to take to BP’s 455,790 barrel-per-day (bpd) Texas City, Texas refinery to process. “There would be a lot of water in it, so it would need to be handled properly when it gets back to the refinery,” Clarkson said.
Fryar said BP’s other activities to address the spill will continue, such as burning the slick at the water’s surface when weather allows, continued efforts by underwater robots to activate the failed blowout preventer, and booms deployed to try to prevent oil from reaching Gulf Coast shorelines.
He said BP also is considering another option known as “top kill” which would involve pumping heavy fluids into the top of the failed blowout preventer to try to plug the leak.
Fryar said that option would be “a couple of weeks away,” as BP continues trying to fix the blowout preventer with underwater robots.
“We are looking at various options around the” blowout preventer, Fryar said. “This is a dynamic situation we find ourselves in, and we continue to work all the options.” (Reporting by Kristen Hays; Editing by Marguerita Choy)