EOR - Enhanced Oil Recovery Several methods used to obtain tertiary recovery from an oil/gas well are clubbed under EOR...
Fundamentals of Enhanced Oil Recovery Larry W. Lake The University of Texas at Austin (512) 471-8233
[email protected] k @ il d
Chapter p 1- Defining g EOR •Overview Overview •Current status •Why EOR •Incremental oil recovery •Comparative performances
Enhanced Oil Recovery Reco er (EOR) is is… • • •
Oil recovery by injection of fluids not normally present in reservoir Excludes pressure maintenance or waterflooding Not necessarily tertiary recovery
Improved Oil Recovery (IOR) is… • •
EOR plus l additional dditi l technologies t h l i dealing d li with ith drilling, d illi production, operations, and reservoir characterization An attempt to avoid negative connotation of EOR
Enhanced Oil Recovery Reco er (EOR) is is… • •
End of the Road "If you intend to select reservoir engineering as a career , then you should steer clear of the more 'career' esoteric subjects such as EOR flooding or the recovery y of highly g y viscous crude oils." • "While EOR may present the more satisfying intellectual challenge, there is also the risk that it may lead prematurely to the dole queue." L. P. Dake, 1994
Recovery y Mechanisms... Primary ay Recovery Artificial Lift
Natural Flow
Pump p - Gas Lift - Etc.
Secondary Recovery y
Conventional Recovery
Pressure Maintenance
Waterflood
Water - Gas Reinjection
Tertiary Recovery Thermal
Enhanced Recovery
Chemical Solvent
Other
Source: Adapted from the Oil & Gas Journal, Apr. 23, 1990
Producing Phases Primary 0.10
Oil Rate
Secondary 0.25
0.10
EL _ P
P
Tertiary
Inj.
Prod. Li Lim
Ave. So
Time
EOR Application Summary •First deliberate application in the 1950s •Approximately 10% of US production from EOR •US accounts for 1/4 of worldwide production •Chemical projects…. •Meteoric M t i rise i and d fall f ll in i the th 1980s 1980 •Least popular EOR today (exc. of FSU, China) •Mostly Mostly polymer because of tax treatment •Fewer than 10 projects •Thermal projects… •Accounts for 50% of EOR oil •Around 60 projects, but declining •Solvent Solvent projects…. projects •Substantial grow in last 10 years to 130 projects About 50% are CO2 projects •About •Storage opportunities
EOR In the US
From Thomas, 2007
EOR Worldwide (2006)
Total EOR=2.5 MMBPD From Thomas, 2007
Major EOR Projects (2006)
From Thomas, 2007
Chapter p 1- Defining g EOR •Overview Overview •Current status •Why EOR
Reserves: What are They? Petroleum (crude, (crude condensate, condensate gas) recoverable From known reservoirs Under p prevailing g economics With existing technology Three categories P Proved d (90% certain) t i ) Probable (50%) Possible (10%) Present reserves = Previous reserves-Production+Additions
Reserves Additions •Discovery Di off new fields fi ld •Discovery Discovery of new reservoirs in known fields •Extensions E t i off known k fi fields ld •Redefinition of reserves because of Economics Extraction technology
The Argument g for EOR • Worldwide consumption increase at a boring rate (2%/yr) •Reserves Reserves not generally replaced •Requires discovery of “giant” fi ld (100 MM bbl fields bbls in i place) l ) •Drilling g alone •Requires large capital investment •Drilling rate inversely correlated with finding rate
Growing Energy Demand Oil Consumption and Industrialization Oil Consumption Increases Fastest During Early Industrialization Per C Capita (Barrrels per Yea ar)
35 30 25
US
20 15
Japan
South Korea
10 5
India 20 000
19 995
19 990
19 985
19 980
19 975
19 970
19 965
19 960
19 955
19 950
19 945
19 940
19 935
19 930
19 925
19 920
19 915
19 910
19 905
19 900
0
China
Source: BP Statistical Review, Respective Census Bureaus, Marc Faber Limited, RJ&A
The Argument g for EOR (cont.) ( ) • EOR applies pp to known reservoirs •No need to find them •Some infrastructure in place •Markets available •Technology is mature and cost effective •65% of oil remains after secondary recovery
Distribution of Ultimate Recovery • Substantial quantities of oil left behind. 1.0
0.8
0.6
0.4
0.2
0.0 Europe*
Former USSR*
Middle East*
Africa* Region
Far East*
Latin America*
US
From Laherrere, 2002
Chapter p 1- Defining g EOR •Overview Overview •Current status •Why EOR •Incremental oil recovery
Definition of Incremental Oil... Oil EOR Operation
Oil P Production Rate
A
Incremental EOR
D
B C
Ti Time
Incremental Oil Recovery y ((IOR)) Oil ((HC)) p produced in excess of existing (conventional) operations Difficulties…. Comingled production Oil from outside project Inaccurate decline estimates IOR IOR recovery efficiency = 100 OOIP
Schematic of Solvent Flood
Fig. 7-1
Drawing by Joe Lindley, U.S. Department of Energy, Bartlesville, OK
Other CO2 Floods... Sundown Slaughter
Means San Andres Unit
18000
(From Folger and Guillot, 1996)
14000
1,000
BOPD
B Barrels/Day
16000
Actual Oil
18% HCPV CO Injection 2
Began (Nov v. '83) CO2 Injecttion
10,000
12000 10000
Recovery, % OOIP P+S To Date 37.2
8000
Continued Waterflood
1988
1989
1990
1991
1992
1993
6000
Continued Waterflood
2000 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992
1994
Year
Year
6.7
Ultimate 47.2 17 (17)* *Original EOR Estimate
40000
1500
1000
P+S
EOR
To Date 21.8
7
Ultimate 21.8 15 (8)*
20000
20 MCF/D CO2 Source Secured
500
Continued Waterflood
0 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992
Year
46% HCPV CO2 Injection I j ti
*Original EOR Estimate
25% HCPV CO Injection 2
30000
10000
R Recovery, % OOIP
Beg gan (Feb. '81) CO2 Injection
BOP PD
50000
To Date 45.2
EOR
BOP PD
60000
P+S
Ford Geraldine Unit
2000
Recovery, % OOIP
CO2 Injection n
70000
Seminole San Andres Unit Began (Mar. '83)
80000
3.2
Ultimate 38.7 11 (7)* *Original EOR Estimate
4000 100 1987
EOR
End of Water Injection 0 1978
1980
1982
Continued Waterflood 1984
1986
Year
1988
1990
1992
Chemical C e ca Flooding ood g
Gradual change to water
Polymer Additives
See below
Surfactant, Polymer, Micellar-polymer Mobility control Surfactant Co-surfactant Co-solvent Polymer Usually 0.1-0.3 PV
No slug
Low salinity Low calcium Usually 0.5 PV
Alkaline Surfactant, ASP Surfactant Polymer Alkaline agent g Usually 0.1-0.3 PV
Chemical Flood Results…. North Burbank Unit
Daqing ASP
Daqing Polymer
Process Variations
Steam soak Steam
Cold Oil
Steam
Shut in
Cold Oil
Cold oil
Inject (2-30 days) Steam
Steam
Hot Water
Oil + Water
Cold Oil
Cold oil
Soak (5-30 days)
Cold Oil
Produce (1-6 months)
Steam Drive
Water
Hot Water
Cold Oil
Oil + Water
Example... Steam Soak - Paris Valley Field
Cruse 'E' (IADB) Expanded Steamflood...
B rning the Oil... Burning Oil
West Buffalo Red River Unit
Primaryy Recovery: y 6.5 % STOOIP
More Variations Using g horizontal wells (SAGD)
Burning tthe eO Oil
Foster Creek (EnCana)
Current production ~ 40000 bbl/d (Q1 2006)
Weaning from Light Oil The Problem: Reserves of ultraheavy (stranded) crude are enormous The Initiative: Make recovery y of this resource economical and environmentally benign - Optimizing SAGD - Alternative heating technologies High Value Products - In situ upgrading • Naphtha Light Processing
Producer Heater
Heater Overburden
High Temperature Causes Long, Horizontal Fractures
¢
• Jet • Diesel • Nat. Nat Gas • Hydrogen • Chem. Feed • Heat
Next Research Phase 2 Step Process (at least) to Commercial
Freezewall Technology For Groundwater Isolation Heater & Producer Wells
Freezewall Test • Football field sized test on 10 acres near
• • •
existing research Test robustness of freezewall barrier Active construction/production p from late ’05 – early ’07 Reclamation 2010
Water & Temperature Monitor Wells
Solid Shale
SURE
Shell Unconventional Resource Energy - White House Briefing April 11th, 2005
Freeze Wells
Natural Fractured Shale Aquifers
filename.ppt
4
Ice Wall on Surface
Athabasca Oil Sands Mining
True in-situ processing is being pursued in the Piceance Basin by y four companies p Shell (Leached zone) Chevron (Mahogany zone)
AMSO (Illitic shale)
ExxonMobil (S li zone)) (Saline
Mahogany zone
2000 0 ft
Heat injection well
Dissolution surface Production well
Saline water
Nahcolitic oil shale cap rock Illitic oil shale 2000 ft
37
aquife er system
1000 ft
Better water quality
Chemical EOR Processes Processes... Process
Ult. Recovery (%)
Typical Agent Utilization
P l Polymer
5
1 lb polymer/ l / inc. bbl
Micellar/ polymer (SP)
15
15-25 lb surfactant/ inc. bbl
Alkaline/ polymer p y
5
35-45 lb chemical/ inc. bbl
ASP
20
Sum of SP/AP
Adj. Sal
10
---
Solvent EOR Processes... Process
Typical Ult. Ult Agent Recovery % OOIP Utilization
Miscible
10-15
10 MCF/inc. bbl
I Immiscible i ibl
5 10 5-10
10 MCF/i MCF/inc. bbl
Thermal Reco Recovery er Processes Processes... P Process
Typical T i l Ult. Ult Recovery % OOIP
Agentt A Utilization
Steam (drive and soak))
50-65
0.5 bbl / net inc. bbl
Combustion
10-15
10 MCF air/inc. bbl
??
??
Like steam
Like steam
SAGD Various EM
