Oil & Natural Gas Projects
Exploration and Production Technologies
A Chemical Enhanced Oil Recovery Project Developed for the Poison Spider
Field Natrona County, WY
The project goal is to demonstrate that the alkaline-surfactant-polymer (ASP)
technology can produce economic incremental oil from a reservoir containing
a highly viscous crude oil.
Arnell Oil Company
Interfacial tension and phase behavior work suggested ASP flooding has potential
for a highly viscous (150-300 cp) reservoir. A number of ASP solutions were
formulated that provided sufficient interfacial tension reductions of more than
10,000-fold and optimum phase behavior to mobilize waterflood residual oil,
based on capillary number theory. Mobility ratios of up to 8.6, low absorption
of ASP components, and incremental oil recovery of up to 18.1% original-oil-in-place
(OOIP) indicated that ASP flooding is a viable technology to produce more of
this type of oil from this reservoir.
The Poison Spider field produces a viscous, 22 degree API gravity black oil
from the Crow Mountain Sand of the Lower Sundance Formation. Sour asphaltic
crude oil, similar to that tested here, is the dominant oil type currently produced
throughout the Rocky Mountain Region. While all reservoirs have unique aspects,
the sampled strata of the Crow Mountain Sand reflected relatively typical characteristics
with fair to good porosity and permeability. It is a mature reservoir relying
solely on gravity drainage for drive.
The direct benefit from this project is that ASP flooding may result in at
least an additional 2,500,000 barrels of oil from Poison Spider Field. More
importantly, however, ASP technology is still relatively new and there are countless
potential applications in mature fields with sour black crude oil throughout
the U.S. The benefit of documenting the feasibility of ASP, under these conditions,
will be to expose small independent operators to the potential of enhancing
production. Further, this study will provide a quantitative foundation upon
which operators can begin their particular evaluation.
In 1919, oil was discovered in a lower horizon of the Crow Mountain Sand at
a depth of 1,400-1,500 feet. The nominal water drive has been depleted for many
years, and the average oil cut of the field now hovers at 7-8%. Current production
for the field is about 100 barrels of oil per day. However, remaining oil in
place at Poison Spider Field is estimated to be at least 14 million barrels.
Therefore, the question is how to optimally produce the balance of the field's
A pilot waterflood has existed in the southeast corner of the field since 1961.
Due to the viscosity of the oil, the effects were positive but not dramatic.
Production near the injection site experienced diminishing returns after a few
years. ASP technology offers the promise of getting more oil into solution and
creating a better bank of oil, resulting in sustained levels of higher production.
The project demonstrated that:
- The reservoir was not sensitive to either NaOH or Na2CO3, and both were capable
of supporting interfacial tension reductions greater than 10,000-fold.
- Water injection alone recovered an average of 53% OOIP, while ASP recovered
up to 81.2% OOIP.
The project has been completed with the exception of a presentation at the
2006 SPE annual technical conference.
Incremental resistance factor for Flopaam 3430s solutions as function of volume
of fluid injected.
Radial coreflood ol rcovery with a Na2CO3, Petrostep B-100, Stepantan AS126,
Flopaam 3630S alkaline-surfactant-polymer solution.
Final Technical Progress Report, December 2004.
Project Start: July 1, 2003
Project End: December 31, 2004
Anticipated DOE Contribution: $100,000
Performer Contribution: $122,278 (55% of total)
NETL - Virginia Weyland (Virginia.firstname.lastname@example.org or 918-699-2041)
Arnell - Doug Arnell (Daarnell@comcast.net or 303-888-0082)