Top kill
{{Short description|Oil well control technique}}
{{wiktionary}}
A top kill is a procedure used as a means of regaining control over an oil well that is been producing crude petroleum or natural gas at a rate that is becoming difficult to govern, and/or is anticipated to become uncontrollable without intervention. This procedure is not used when control has been completely lost over the well, such as in a blowout. The process involves pumping heavyweight drilling mud or drilling fluid downwards into the well. This procedure is expected to stop the flow of oil and gas from the well by neutralizing the pressure differential between the source and the top of the well.
A further step could be sealing the well completely, often with cement.
In use
The top kill procedure was used to plug flaming oil wells, blown up by retreating Iraqi forces, in 1991, during the Gulf War.{{cite news |url=http://www.chron.com/disp/story.mpl/business/6991278.html |title=New tactic might seal leaking well sooner, BP CEO says |date=5 May 2010 |accessdate=29 May 2010 |author=Brett Calnton |publisher=Houston Chronicle}}
This technique came to prominence during the 2010 Deepwater Horizon oil spill when it was used in an attempt to seal a seafloor oil well after the failure of the blowout preventer.{{cite news |url=http://news.bbc.co.uk/1/hi/world/us_and_canada/10159626.stm |title=What is a 'top kill'? |last=Rohrer |first=Finlo |date=27 May 2010 |accessdate=27 May 2010 |publisher=BBC}} However, it failed to block the flow of oil.{{cite news |url=http://www.timesonline.co.uk/tol/news/world/us_and_americas/article7140280.ece |title=BP struggles to stem gush of reproach |date=30 May 2010 |accessdate=30 May 2010 |author=John Harlow |work=The Times}}{{dead link|date=September 2024|bot=medic}}{{cbignore|bot=medic}}
References
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