Monday, June 7, 2010

CLEAN KILL: USE THE GULF TO SAVE THE GULF

PREAMBLE

The author is not a movie star, nor a movie director. The author has 40 years experience in petroleum worldwide, including the contingency and recovery plans for the Kuwait blowout fires. He has worked in technical and engineering areas related to oil production, computer simulation. He is a degreed professional engineer with degrees from Stanford (PhD), Oklahoma (MSc) and Colorado School of Mines (BSc). He is also a former Distinguished Professor of Petroleum Engineering at the University of Oklahoma, where in 1974 he developed the first BlowOut Training School to train and certify drilling personnel worldwide in well control practices.

The current BP solution can be easily modified to allow 
almost 100% stoppage of oil flow from the well.


INTRODUCTION

As of June 7, 2010, BP indicated that it was collecting 11,000 barrels of oil per day. That still leaves between 5,000 and 10,000 barrels of oil spilling into the Gulf of Mexico daily. By the end of August there would be an additional 40,000,000 gallons of oil hitting the beaches.

This "Clean Kill" process shown here could be implemented in 2 days and shut down the oil flow from the well. Most of the equipment is already in place. BP could save several BILLIONS of Dollars. The people of the Gulf Coast would get their lives back sooner.

BP should stop their current process and initiate the "CLEAN KILL" as soon as possible. It is a better engineered approach with the ability to minimize oil spillage, or to control the total oil loss.


THE CLEAN KILL TECHNIQUE

This technique shown herein is a result of 40 years professional experience in oil and gas engineering, training and teaching by the author.

The "Clean Kill" technique uses seawater and the processes are based on strict engineering analysis and historical implementation.

Scientific Basis:  "High Volume flow of liquids create frictional resistance which increase the  pressures acting on the fluids. This pressure is translated down the wellbore helping to shut off the oill flow".

Operational: The overall process focuses on slowing and actually shutting the oil flowing from the well by using of the frictional pressure developed by seawater being rapidly pumped through the BOP and a modified choke instead of the LMRP currently being used.

A COMPLICATION:
It has been reported that there is a break in the wellbore at 1,000 feet below the mud-line. The seawater circulation proposed in this "clean kill" proposal would still be effective in creating a back pressure sufficient to limit the vertical flow of oil and subsequently at high sea water injection rates, lower the oil column below the reported break point. This lowering of oil column, seemed to have happened during the aborted "top kill". In any case the loss of fluid will still continue EXCEPT that in the "clean kill" process the loss would be seawater and not OIL or MUD.

The "top kill" did work temporarily, even with the wellbore break. It did set up a temporary "dynamic kill", however they only had 50,000 barrels of mud on site. They could only pump for a limited amount of time. This "clean kill" approach has an infinite amount of seawater to inject, forever. The whole Gulf of Mexico. The "clean kill" process will STOP the oil flow into the wellbore and continue to circulate seawater until the relief well is finally drilled.


The pictures illustrate the process.

CLICK ON IMAGES TO ENLARGE THEM
.
Figure 1. CLEAN KILL Overview.



Figure 2. Modify LMRP cap by adding choke device.
Figure 3. Pressure Increase with High Flow Rates

Figure 4. Pressure Comparison
Modification of LMRP Cap Device with Choke type insert.

Possible modification to HOLD DOWN new cap.


The existing equipment on the drill-ship location is used in the following steps.

STEPS

1. Modify the LMRP cap by adding a choke device which is attached to the existing cut riser stub. See generic graphic Fig. 2.

2. Connect the BOP to the existing pump system on the surface and suck seawater from the Gulf of Mexico and pump down to the BOP.

3. Pump seawater at increasing high rates down through the BOP and up through the choke device through the riser stub. The high seawater flow rate and the flow through the choke device, create a frictional back-pressure which raises the bottom hole pressure in the well and eventually slows down the oil flow in the bottom of the well-bore. See pressure addition in graphic Fig. 3 and Figure 4.

4. Oil and seawater will flow commingled up through the BOP and exit as a dark colored plume.

5. The plume exiting the wellhead will gradually change from dark cloudy to a clear cloud as the fraction of oil decreases as the well pressure increases above the oil.

6. This color change should occur in a matter of hours. Continue visual inspection of the plume to monitor oil being spilled.

7. Continue circulating seawater for weeks until the relief wells are in place and implemented.

8. Balance the flow rates to maintain a Clean Kill without creating a down-hole blowout by over pressuring the well bore.

COSTS

Estimated cost to run the pumps is less than $40,000 per day for a 50,000 HP pumping system. CHEAP!!


RESULTS

No more oil spilled into the ocean. The plume should be milky clear.  The oil rests below the flowing seawater in the well-bore and is held in "dynamic equilibrium"  AS LONG AS WE KEEP PUMPING  seawater. If we quit pumping oil flows again, and we have to restart the process.

NOTES

There is no need for a perfect seal in the LMRP cap, since the leak would help the choking effect of seawater flow.

This process can be tested and verified by BP in two ways.

First, a laboratory test run can be made using a flow loop at any of the exiting universities or petroleum service labs around the country.

Second, a computer simulation model can be made using any of the existing kill simulators available in the industry to correctly size the choke device.

In addition, the author/developer fully expects that use of this process or any derivatives thereof would be fully remunerated by BP in a manner commensurate with the savings that accrued by BP and its associate companies.

Signed:

Dr. Henry Crichlow P.E
Author/Developer
Registered Professional Engineer
330 W Gray St, Suite 504
Norman, OK. 73069
(PhD, Stanford, MSc Oklahoma, BSc. CSM)

Email:
henry.crichlow@sbcglobal.net

henry.crichlow@gmail.com