Ekofisk Bravo blowout incident happened when performing workover operation. If you study in the oilfield industry about well control incidents, there are several cases when the well was unable to control during workover operation. This is what personnel working in this industry needs to learn and fully aware of the hazard which could be occurred and this can affect lives, environment, etc. This is one of the reason why we always emphasize the important of well control in every operation.
The Ekofisk Bravo Platform Blowout
The Ekofisk Bravo Platform is located towards Ekofisk field’s north and is one of the two prime wellhead production facilities of Ekofisk. However, on April 22nd, 1977, it went through a major blowout which is regarded as the biggest oil spills till date at the North Sea.
The Ekofisk B blowout took place when workover was being carried out at B-14 production well where they were busy pulling about 10,000 feet of production tubing. Before the task, the production Christmas tree valve stack was removed. Besides, the BOP was not installed. However, the well kicked and wrongly installed while the downhole safety valve failed, which caused immediate blow out of the well with wild release of gas & oil. However, fortunately the crew onboard was evacuated safely through lifeboats and was later transferred to the supply vessel. Miraculously, no one was injured.
This event led to wastage of approximately 28,000 barrel/day, later resulting into overall discharge of 202,380 bbls. Around 30-40% oil was assumed to be evaporated and the overall spill estimate by the Norwegian Petroleum Directorate was to be considered around 80,000 bbls & 126,000 bbls.
Finally, after 7 days, the well was capped in April 30th, 1977. However, higher air temperature & rough seas helped the break-up of the most of the oil. Further investigations concluded that there was no major damage to the environment & shoreline pollution. Besides, there was no major damage to the platform.
The official inquiry later concluded that the blowout was the result of human error which later caused mechanical malfunction of safety valve. Such errors included were the faults in equipment identification, misjudgment, inappropriate planning & well control, and installation documentation. This blowout was regarded as the major blowout of the North Sea’s history as it was the very first North Sea oil spill. However, the ignition of gas & oil was prevented that led to no casualties and major injuries at the time of evacuation.
Additional Information about Ekofisk Field
Ekofisk is basically a block of oil field that belongs to Norwegian sector at North Sea located approximately 200 miles (320 Km) southwest of Stavanger. It was originally discovered by Phillips Petroleum Company in the year 1969 and is considered to be the foremost oil field of the North Sea. In fact, it was here when the oil was first discovered, after drilling more than 200 wells at North Sea that succeeds the discovery of Groningen gas field. In the year 1971, Phillips initiated to produce for the tankers directly from 4 subsea wells. However, today they plan to continue producing oil till 2050.
The Ekofisk reservoir comprises of Cod, West Ekofisk, Ekofisk, Tor, Eldfisk, Albuskjell, Edda & Embla oil fields. Besides this, the Ekofisk Center is an immense complex of structures & platforms that acts as a transportation hub for neighboring fields too, like Valhall, Gyda, Hod, Ula, Heimdal, Statfjord, Tommeliten & Gullfaks. The entire complex comprises of total 29 platforms. The oil that is produced is supplied through Norpipe oil pipeline to Teesside Refinery in the England. The natural gas is supplied through Norpipe gas pipeline to the Emden in Germany.