Deepwater Horizon: Riser tube tool at work, second well spuds

The riser insertion tube tool (RITT) containment system is in place in the end of the leaking riser, and operations started flow oil and gas to to the drillship Discoverer Enterprise on the surface, BP reports regarding the Deepwater Horizon Gulf of Mexico oil spill site status.

Offshore staff

HOUSTON -- The riser insertion tube tool (RITT) containment system is in place in the end of the leaking riser, and operations started flow oil and gas to to the drillship Discoverer Enterprise on the surface, BP reports regarding the Deepwater Horizon Gulf of Mexico oil spill site status.

Produced oil is being stored on the vessel while produced gas is being flared. However, BP says, it will take time to increase flow through the system and to maximize the proportion of oil and gas emanating from the riser for transportation to the sea surface.

The RITT is constructed from 4-in. (10-cm) diameter pipe. The design allows one end to be inserted into the broken riser pipe, and the other to be connected to a drill pipe and riser from the Discoverer Enterprise. The procedure – never attempted before at such depths – involves inserting a 5-ft (1.5 m) length of the specifically designed tool into the end of the existing, damaged riser from where the oil and gas is leaking. The RITT also allows methanol to be injected to mitigate against the formation of gas hydrates.

BP points out that this is a new technology, and its effectiveness in capturing the oil and gas remains uncertain. Other containment options are under review and the company continues to pursue options to shut off the flow of oil through interventions via the well's BOP. The main thrust will involve a “top kill” operation under which heavy drilling fluids will be injected into the well to control the flow, followed by cemening to seal the well. This could be combined with “junk shot,” injecting a variety of materials under pressure into the BOP to seal off upward flow.

Work continues on the first relief well, which started on May 2. The DDII drilling rig is drilling the second relief well now too. Both wells should take three months to complete from the commencement of drilling.

As for the containment effort, work continues to collect and disperse oil that has reached the sea surface. Operations to skim oil from the surface have now recovered around 151,000 Bbbl of oily liquid. Almost 1.7 million ft (518,000 m) of boom has been set down to prevent oil reaching the coast, including over 400,000 ft (121,920 m) of sorbent boom.

05/17/2010

More in Deepwater