I was the first petroleum engineer of Pakistan or an oil technologist, as I was called at that time, with an honors degree from the University of London, U.K. I learned my trade by doing it. The list covered the gamut of every facet of an oil man’s life. I sat on drilling rigs looking at drill cuttings; checked mud pits looking for telltale signs of oil, participated in making casing plans, did cement jobs and acid jobs. When the drill bit reached the production horizon, I did Johnston testing, also known as drill stem testing. I was responsible for single and dual completions, in fact ran and set the Baker Packers at appropriate production levels. I had to learn it and did it all.
When Dhulian well 42 blew out during Johnston testing, every rig hand ran off the rig’s floor. But I had designed the ‘test Christmas tree,’ and I didn’t run. The well had to be controlled. The fear of the well catching fire was the farthest thing from my mind. I shouted orders to my crew on ground, away from the rig floor, asking them to open the adjustable ‘bean’ full out; open the bypass valve so that oil pressure at the test Christmas tree would ease some, allowing me to shut off the open flow. They listened while I–completely covered with oil and drilling mud, hardly being able to see because my glasses were coated with well fluids–manipulated controls on the rig floor. The well quieted down. We brought in one of the best wells in the field. I survived to write this story.
I designed oil/water separators and had them constructed to recover countless barrels of waste oil from the oilfield’s separation facilities and had it pumped to the refinery. I learnt that the basic of a good well completion, in addition to a well-designed Christmas tree, was an inline, bottom hole, automatic shut down valve. A device which shuts down flow from the well should anything go wrong at the surface.
The blow-out at BP Global Oil Platform, and the resulting oil slick offshore Louisiana, has global implications for the oil industry. If I were the disaster mitigation czar, I would have put into effect the following actions immediately following the blow-out. These should be taken even now, and all can be carried out concurrently:
- Contain the oil
- Recover the already leaked oil
- Control the leak
- Investigate the cause of failure
What do the actions involve?
1. CONTAIN THE OIL:
Using a pipe-lay barge, I would lower an appropriately sized pipe, all the way from the sea’s surface, down to and over the Christmas tree of the leaking well. Our objective would be to surround the Christmas tree with the pipe. If the cross section of the Christmas tree is too large, an appropriately sized pipe can be fabricated to enclose it and a reducing device installed on top of it so that off-the-shelf pipe can be used to create a vertical riser pipe, all the way to the sea surface. The leaking oil is now contained.
The riser should project high above the water surface, acting as an atmospheric tank.
Then, we pump out the oil from the riser pipe into an oil tanker waiting to receive it.
2. RECOVER THE LEAKED & LEAKING OIL:
Corral the oil that is spreading out from the leaking site. Convert an oil tanker, more if required, into an oil/water separator. Bring the oil/water separator tanker to the area where the oil has been corralled.
3. CONTROL THE LEAK:
Directionally drill a relief well to take the pressure of the leaking well. Once the new well hits the leaking one, seal it per the standard industry practice.
4. INVESTIGATE THE CAUSE OF FAILURE:
Installing a down-hole automatic shut-down device in the flow tubing is standard practice in all producing wells, both onshore and offshore. Did this well have such a device? If it didn’t, why not? If it did, what went wrong with the device?
About The Author:
Zaheer Jan is an independent oil/gas consultant who has served as production/field development/well completion engineer on some of the highest pressure oilfields in the world, in Khaur and Dhulian, Pakistan; manager of pipeline engineering on the $24.0 billion Alaska Natural Gas Transportation System; and consultant to the state of Alaska, PEMEX and Occidental Oil of Pakistan. E-mail: email@example.com.