Wednesday, May 12, 2010

What are the fail safes on an offshore oil rig


by Peter Stern

There are several fail safes considered standard mandatory safety equipment on every modern oil drilling rig. Each safety procedure and item has been proven over time to be a major factor in saving human lives, securing capital equipment and protecting the environment by shutting-down a potential and/or pending oil spill before irreparable harm is done.

The main fail safe of defense on an oil rig is the blowout preventer (BOP), which is a combination and stack of valves that may intercept and close the wellhead immediately in the event of an emergency where a swell of pressure mixing with oil and/or gas rises up, which if not shut-down may cause an explosion causing severe damage to the crew and rig and thereafter possibly permitting oil to disperse into deep waters. The BOP has 3 fail safe options built into its capability. The first is the manual shutdown practiced by the crew during operation via random drills. The second fail safe option after an explosion is an immediate and automatic self-activation of the BOP via an acoustic switch to shut-down operation and to stop oil from spilling. The third fail safe option of the BOP is to activate via electronic remote. The BOP installed on the Deepwater Horizon drilling rig did not function in any of the 3 fail safe modes; consequently, there was an explosion that killed 11 of the crew and then allowed the release of oil into deep sea waters.

Once a spill occurs it becomes a losing proposition for the environment and all concerned parties. While the damage is done for the most part, it becomes a battle against the clock as to the severity of the spill. It is a race to contain the spill as much as possible. The standard operation procedure is to use chemicals that attach to the surface oil to hold the slick together, while using floating pontoons to try to lock-in the spill, preventing it from spreading further out to sea or possibly threatening the shoreline.

The following option is not a certainty in stopping an oil spill, but there is a good chance it will work. Another drilling rig is set up and the drill is angled to intercept the source flow of oil by drilling into the underwater pipe. The flow of oil is then diverted to a storage facility, e.g., a tanker, which is then taken to a safe destination.

The next option is to try to cap the source of the underwater oil leak. Capping the leak slows down the spill process and enables more time to seal the leak, recapture the underwater oil and also permits the cleaning up of the environment. However, building and/or assembling the capping device and the housing for the oil recapture takes several months to complete and install.

While there are several fail safe options on an oil rig, many will say that it is not enough to protect the crew and the environment. In addition, the maintenance, safety precautions and reliability of the devices have been proven to be faulty at best and must now undergo further scrutiny, improved oversight and better maintenance procedures and requirements. Oil companies must step-up to a safety-first priority, not profits first.

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