EOR PERFORMANCE AND MODELING
Potential for Additional CO2-Flood Projects in the US
Introduction
US conventional crude-oil production
continues to decline while demand for
crude and finished products rises. According to the US Department of Energy
Energy Information Administration
(US DOE EIA) and shown in Fig. 1, the
US demand will be greater than 27 million B/D by 2030, while total production
will be less than 10 million B/D.
Four factors were identified that will
have a significant effect on widespread
implementation of CO2 EOR.
• Target resource
• Technology
• Availability of CO2
• Economics
Target Resource
There are 1,673 reservoirs onshore
in the continental US that are canThis article, written by Senior Technology
Editor Dennis Denney, contains highlights of paper SPE 113975, “The Potential
for Additional Carbon Dioxide Flooding
Projects in the United States,” by Hitesh
Mohan, SPE, Marshall Carolus, SPE,
and Khosrow Biglarbigi, SPE, Intek,
prepared for the 2008 SPE Improved Oil
Recovery Symposium, Tulsa, 19–23 April.
The paper has not been peer reviewed.
30
27.65
25
20
Million B/D
There is renewed interest in carbon dioxide enhanced oil recovery (CO2 EOR).
Growing concern about climate change
and greenhouse gases has increased
interest in carbon capture and sequestration. CO2 EOR provides a value-added
opportunity to increase crude-oil production while sequestering substantial volumes of industrial CO2. An analysis was
conducted to determine the incremental
domestic production that could be realized if industrially produced CO2 were
available for EOR. Challenges include
available volumes of CO2, infrastructure
requirements, and prices of the CO2.
US Consumption
20.74
Imports
15
12.11
58% includes finished
products
10
9.65
8.63
US Production
5
18.00
65% includes
finished
products
(Includes crude, NGLs,
and refinery gains)
2004
0
1975
1980
1985
1990
1995
2000
2005
2010
2015
2020
2025
2030
Source: US DOE EIA “Annual Energy Outlook 2006”.
Fig. 1—US consumption and demand projections. NGLs = natural-gas
liquids.
didates for CO2-miscible flooding.
Fig. 2 shows the reservoirs that
were identified on the basis of the following criteria.
• Gravity greater than 22°API
• Reservoir pressure greater than the
minimum miscibility pressure
• Depth greater than 2,500 ft
• Oil viscosity less than 10 cp
• Current oil saturation greater than
20%
• Either sandstone or carbonate rock
Technology
CO2-EOR technologies have been
demonstrated to be profitable in commercial-scale applications for nearly
30 years. As of 2006, 80 CO2-EOR
projects in the US had a combined production of 234,000 BOPD. Ten of these
projects were started between 2004 and
2006. Of the projects active in 2006, 58
are in the Permian Basin. The reason
is partly because of the prevalence of
candidate reservoirs in that region, and
because of the steady availability of
natural CO2.
Natural Sources of CO2
The US produces approximately
3 Bcf/D of CO2 from natural sources
in the Permian Basin, Colorado, and
Mississippi, as well from an ammonia plant in Oklahoma. Of the available CO2, 78% is sent to the Permian
Basin. The rest is available in the Gulf
Coast of Louisiana, in Colorado, and
in Wyoming. The CO2 produced at the
Great Plains Coal-Gasification Plant in
North Dakota is sold to the Weyburn
project in Canada and was not considered for this analysis.
Industrial Sources of CO2
Currently, there are a few plants, including a Texas gas plant and an Oklahoma
fertilizer plant, that provide CO2 for
EOR. These existing sources are listed
in the natural-source category. For this
study, other existing industrial sources
were examined to determine the additional volume of CO2 that could be
provided to EOR projects in the US.
The primary source of emission
data for this analysis was the National
For a limited time, the full-length paper is available free to SPE members at www.spe.org/jpt.
JPT • JANUARY 2009
55
Fig. 2—US candidate CO2-EOR fields.
Ethanol plants
Plants >> 50
50 Bcf/yr
Bcf/Yr
Ethanol plants > 1 Bcf/yr
Refineries
Ammonia plants
Cement plants
Hydrogen plants
Fossil-fuel power plants
Fig. 3—Industrial sources of CO2.
Fig. 4—Mapping industrial sources to the candidate fields.
56
Carbon Sequestration Database and
Geographic Information System, funded by the National Energy Technology
Laboratory and maintained by the
Kansas Geological Survey. The database provides source data for 56.5 Tcf
of industrial CO2 emissions. Sources
considered include fossil-fuel power
plants, refineries, cement plants,
hydrogen plants, ammonia plants,
and ethanol plants. These sources
were screened initially according to
their proximity to candidate EOR
fields. The fossil-fuel power plants
were further screened according to
the emission volume. Fig. 3 shows
the industrial sources considered in
the study.
Fossil-fuel power plants and refineries represent approximately 90%
of the total CO2 emitted. However,
CO2 emissions from ethanol plants
are expected to grow steadily. Up to
25 Tcf of industrial CO2 can be made
available each year through capture
from these industrial sources.
Determining Wellhead
Costs for Industrial CO2
The wellhead cost for industrial
sources of CO2 have two main components—capture and transportation. The transportation costs were
assumed to be pipeline tariffs and
were calculated as follows. (1) Maps
of industrial sources and candidate
fields were overlaid to define prospective geographic regions. (2) Average
distances between the sources and
fields were calculated for each type of
industrial CO2. (3) A pipeline-tariff
model was developed and used to
calculate the minimum tariff required
for each source. Fig. 4 shows the
distances between four refineries and
a large number of candidate fields
in the midcontinent region. In this
illustration, the tariff would be for
an average distance of 158 miles.
This procedure was applied to each
geographic region and source of CO2.
The capture costs are technology-specific and can vary drastically depending on the plant type.
Total Volumes of CO2 Available
Up to 26 Tcf of natural and industrial
CO2 could be available. Fossil-fuel
power plants and refineries represent
approximately 90% of the total CO2
available. As a result, the east-coast
region has an available CO2 volJPT • JANUARY 2009
1,400
6,000
5,000
1,000
4,000
800
3,000
600
2,000
400
1,000
200
0
2008
CO 2 Injection, MMcf/D
Oil Production, million B/D
1,200
0
2012
2016
2020
2024
2028
Year
Fig. 5—US onshore Lower-48-States crude-oil production and CO2
sequestration from additional CO2-flood projects.
ume of approximately 14 Tcf/yr. The
Gulf coast contains a large portion of
the nations’ refineries, and thus produces approximately 5.5 Tcf/yr. The
1Tcf/yr of CO2 available in the
southwest region comes predominantly from natural sources and
Permian Basin refineries. Other significant sources of CO2 are the Rocky
Mountains with more than 3 Tcf
and the northern Great Plains with
1.2 Tcf.
Total costs can be as low as
USD 0.92/Mcf for ammonia and
hydrogen plants, and as much as
USD 3.22/Mcf for fossil-fuel power
plants. Costs for ethanol plants can
be as low as USD 0.99/Mcf, and CO2
emissions from ethanol plants are
expected to grow steadily in the near
future. While wellhead costs for all
plant types fall within a wide range,
technological improvements continue to yield significantly lower capture
costs for newly built plants.
Technology and market constraints
prevent the total volumes of CO2
from becoming available immediately. Development of the CO2 market
has three periods: technology R&D,
infrastructure construction, and market acceptance. Capture technology
is developed during the R&D phase,
and no CO2 would be available during that time. During infrastructure
development, the required capture
equipment, pipelines, and compres-
JPT • JANUARY 2009
sors are constructed, and no CO2
would be available. During the market-acceptance phase, the capture
technology would be implemented
and volumes of CO2 would become
available. The maximum volume
of CO2 available will be achieved
when the maximum percentage of the
industry that will adopt the technology does so. This point provides an
upper limit on the volume of CO2
that will be available. With these
assumptions, the industrial CO2 from
more-concentrated sources, such as
the ammonia, hydrogen, and ethanol
plants, will become fully available
after 14 years. The total volumes of
CO2 from refineries and fossil-fuel
power plants will become available
after 21 years.
Economics
The economics of each project was
evaluated with a detailed cash-flow
model for all natural and industrial
sources of CO2 at oil prices between
USD 45/bbl and USD 60/bbl. The economically viable projects then were
checked for availability of sufficient
CO2 at a regional level. The leastexpensive sources of CO2 were considered first. Projects that could be
supplied by a single source of CO2 for
the life of the project were aggregated
to the regional and national levels to
determine the benefits of widespread
CO2 EOR.
Benefits of Additional
CO2-Flooding Projects
Fig. 5 shows US incremental-oil production and CO2 sequestration from
additional CO2 projects. By 2030, an
additional 1.2 million B/D of incremental production could be realized
while approximately 5 Bcf/D of CO2
would be sequestered. The sequestered CO2 is the difference between
the volume of CO2 injected and the
volume of CO2 produced. The “twohump” shape of the CO2 curve is the
result of additional CO2 from refineries and power plants becoming available after 2021 for additional projects.
Most of the production will come
from the southwest. However, additional production could be realized
from all other regions, with the midcontinent, the northern Great Plains,
and the west coast providing production of approximately 250,000 B/D.
Conclusions
Widespread use of industrial CO2 for
EOR could increase the available volume of CO2 from 3 Bcf/D from natural sources to approximately 70 Bcf/D
from a combination of natural and
industrial sources. This CO2 would
be available for the Permian Basin
and for all other parts of the US. By
providing a steady source of CO2,
at prices between USD 1/Mcf and
USD 3/Mcf, more than 200 CO2-EOR
projects, with incremental production reaching 1.2 million B/D, could
be realized. At the same time, these
projects would provide the opportunity to sequester nearly 5 Bcf/D
of CO2.
Limitations
This analysis has important limitations.
• The availability of CO2 from
industrial sources will depend on
industry participation.
• The analysis assumes that capture
technologies will be successful and
available for implementation within
3 to 6 years.
• The analysis does not consider
the competition between CO2 EOR
and other EOR technologies.
However, none of these limitations
invalidate the results of this analysis
if these results are viewed in terms
of their intended purpose, which is
an estimate of the upside potential of
JPT
CO2 EOR.
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