0. EOR-Knowledge Base (KB) Screening/Design Tool
KOC &
Dr Ali Qubian - TPL Snr Specialist – SS Team R&T
Huda Al-Enezi & Heba Bo Sana
PE Conference- Madrid
June 2017

1. Content EOR screening concept and methodology
Knowledge Base (KB) EOR Expert system (ES) Features/functionality
Demonstration of the KB EOR

2. Two notes: AL is primary? MEOR-Low sal-Hybrid

3. Expansion/Full-Field Implementation
Further tuning & revisiting to the existing EOR workflow processes
Thanks
Laboratory work and modeling-Recipe
SWCT
Pilot Implementation
Scaling up
Expansion/Full-Field Implementation
Screening & reservoir selection
Validate RF
& Recipe
Pilot objective(s)
Refine uncertainties & broader economics
Promising RF & Recipe
Reservoir & fluids
Decision
Gate 1
Decision
Gate 2
Decision
Gate 3
Pre-pilot phase
Piloting phase
FSI
Pilot design
Re-visiting-Tuning ?
Go ahead
Conservative approach
Peer Review
Slightly relaxed approach
It is all about confidence building after meeting the workflow checklist items

4. 1) EOR screening concept and methodology
The objective of the screening process is to decide which EOR methods may be applicable in a reservoir and which definitely are not. The starting point is a set of basic properties that should be available for any reservoir.
Screening criteria are based on physical principles associated with each method and on economic assumptions. There is some subjectivity and there will be minor variations between authors on specific requirements.

5. EOR screening

6. Selection of suitable reservoir(s) candidate for both CEOR & GEOR
Screening
Parametric screening
- US DOE 1984
- Dickson et al. 2010
Geological screening
Logging
RFT
MDT sampling
RCA,
SCAL
Mineral study
PVT analysis
Promising Results:
Selection of suitable reservoir(s)
candidate for both CEOR & GEOR

7. Conventional screening
1984 USA DOE-NPC Goodlett
1997 Taber et al. Papers
2010 Dicxson

8. Advanced screening

9. Advanced- AI
This project will develop a toolbox that can be used to help reservoir engineers in identifying the optimum production scenario using EOR techniques. The proposed toolbox integrates reservoir properties, project design, and hydrocarbon production in a flexible way. Therefore, reservoir engineers can use it in three different approaches as follows:
1- Knowing reservoir properties and project design parameters, the toolbox can be used to predict the performance of certain EOR/IOR process in terms of hydrocarbon production.
2- Given reservoir properties and hydrocarbon production target, the toolbox can be used to predict the project design.
3- Knowing the actual hydrocarbon production and the actual project design, the tool box can be used in a reverse order to check for the accuracy of reservoir properties!.

10. U.S. DOE 1984 Screening Criteria

11. (Based on the 1984 NPC chart)
Screening Criteria
(Based on the 1984 NPC chart)
Waterflooding:
50 cp is taken as the upper viscosity limit. Poor sweep and fractional flow behavior is assumed for more viscous oils.

12. Screening Criteria Steam Stimulation:
The primary requirement is unfulfilled primary production potential (either from pressure depletion or gravity drainage)
This is assumed possible if oil viscosity > 100 cp.
In order to make efficient use of steam, pay thickness > 20 ft (low percentage heat losses) and  x SO > 0.1 (high OIP per unit rock volume) are also required.

13. Screening Criteria Steam Flood:
Oil viscosity (<20,000 cp), average permeability (>250 md), and transmissibility (> 5 md-ft/cp) limits are set to ensure that steam can be injected and oil can be produced in a reasonably short time.
For depths greater than 4000 ft, wellbore heat losses are assumed to be too high.
At reservoir pressures greater than 1000 psi, economics are assumed unfavorable because of high steam temperature.

14. Screening Criteria Steam Flood (continued)
In order to make efficient use of steam, pay thickness > 20 ft (low percentage heat losses) and  x SO > 0.1 (high OIP per unit rock volume) are also required.
Although no lower limit is placed on oil viscosity, it is unlikely that reservoirs with very low viscosity oils will meet the other requirements

15. Screening Criteria In-Situ Combustion:
Oil viscosity (<5,000 cp), average permeability (>35 md), and transmissibility (> 5 md-ft/cp) limits are set to ensure that air can be injected and oil can be produced in a reasonably short time.
For depths greater than 11,500 ft and reservoir pressure greater than 2000 psi, air injection costs are assumed too high.

16. Screening Criteria In-Situ Combustion (contiued)
Minimum pay thickness (h > 20 ft) is required in order to sustain a combustion front at reasonable air flux.
Minimum oil content ( x SO > 0.08) is required to have enough displaceable oil for favorable economics.
For depths less than 4,000 ft., it is assumed that steam flooding is preferred.

17. Screening Criteria Hydrocarbon Miscible Rich Gas Flood:
Obtaining miscibility with LPG-enriched natural gas is assumed to be possible only for pressure > 1,000 psi and for oil gravity > 25 API.
CO2 Flood:
Reservoir pressure must be greater than the CO2 flood MMP at reservoir temperature as obtained from correlations.
Miscibility is assumed unlikely for oil gravity < 25 API.

18. Screening Criteria Polymer Flood:
Reservoirs with oil viscosity > 100 cp are assumed not likely to benefit from mobility control.
Permeability > 20 md is required to flow the viscous polymer solutions.
Reservoir temperature < 190 F and brine salinity < 100,000 ppm TDS are required for polymer stability and effectiveness.

19. Screening Criteria Micellar-Polymer Flood:
MP floods can be designed to control mobility only for oil viscosity < 40 cp.
Permeability > 40 md is required to flow the viscous fluids involved.
Reservoir temperature < 190 F and brine salinity < 100,000 ppm TDS are required for polymer stability and effectiveness.

20. Screening Criteria Alkaline Waterflood:
The oil should contain reactive acids. (Acid number > 0.5 meq KOH/g).
Reservoir temperature < 200 ºF is required to minimize rock-chemical reaction.
Oil viscosity < 90 cp. and pemeability > 20 md. are required to allow flow of mobilized oil and emulsion banks.

21. Screening Examples EOR Screen: Duri (Indonesia)
k md Tres F
Φ o at Tres cp
So oil gravity API
depth 600 ft water salinity ppm
Pres 50 psi
EOR Screen:
Waterflood: high viscosity
Steam Stimulation: low pressure
Steam Flood OK
In-Situ Combustion: shallow (steam preferred)
Rich Gas Flood: pressure & API both low
CO2 Flood: API low
Polymer Flood: high viscosity
M-P Flood: high viscosity

22. Screening Examples EOR Screen: Prudhoe Bay (Alaska)
k 400 md Tres F
 o at Tres cp
So oil gravity API
depth 8800 ft water salinity unknown
Pres 3600 psi
EOR Screen:
Waterflood: OK
Steam Stimulation: low viscosity
Steam Flood too deep
In-Situ Combustion: high pressure
Rich Gas Flood: OK
CO2 Flood: OK ( psi MMP)
Polymer Flood: high Tres
M-P Flood: high Tres

23. Radar plot - prioritization

24. 1997 Taber et al. Papers
Update to NPC EOR study based on field experience and oil price trends
References
Taber et al: “EOR Screening Criteria Revisited – Part 1: Introduction to Screening Criteria and Enhanced Recovery Field Projects” and “Part 2: Applications and Impact of Oil Prices”, SPE Reservoir Engineering (August, 1997) pp

29. Depth limitation

35. 2) EOR Knowledge Base (KB) EOR Expert system (ES) Features/functionality
The developed ES is a unique web portal EOR KB, which will be accessible by subscription and is updated periodically with new case studies and statistics.
The objectives of this ES are to:
Facilitate effective technology transfer of industry-wide EOR best practices, lessons learned etc.
Assist and benefit operators by providing EOR analogs and project information and capturing the study results in a web portal knowledge base that will help maximize knowledge transfer to the industry, and
Enable operators to screen and prioritize EOR techniques potential as applicable to their specific field opportunities.

36. Benfits of the ES EOR KB is a tool that allows users to:
- Input oil and reservoir properties to a screening interface where they can obtain recommendations of best EOR fit.
- Provide GIS interface with locations of EOR projects worldwide with details on the map including adding new ones on map locations, and
- It contains a wiki with articles regarding EOR

38. Home-Map-Technical screening-Wiki-Economic

39. Map Global EOR projects and briefs- you can add your own ones
Color codes for map and screening Tables
Project Type
Color
Polymer
Steam
Nitrogen & Flue Gas miscible
Chemicals
CO2 Miscible
Combustion
Hydrocarbon miscible
Immiscible Gas

40. Screening methodology
User interface is provided for each EOR method to calculate. Every method has a FORTRAN program that does calculations in the background. All inputs are formatted into a text file that is compatible with the FORTRAN program. That program calculates and gives results in a text file format. EORKB reads that output text file and displays results on screen. Raw output files are available for download on results page.
Users can save their input parameter set for later use. Save, open, delete options are provided on top of the input screen.
Screening results are shown in tables (with color codes as below). Each property shows its best value and average value. Green is for best and Red is not matched. Light green is for slightly

42. This tool calculates according to Taber 1997, Dickson et al
This tool calculates according to Taber 1997, Dickson et al. 2010, Goodlett et al papers.

43. Sample case

44. Screening output (Tables and Radar plot): Each property shows its best value and average value. Green is for best and Red is not matched. Light green is for slightly
Output

45. Custom screening: for both adding new customized EOR method and modifying cells content and value ranges

46. Economics:
The tool receives input values for discount rate, revenue interest, oil price, gas price, oil tax, gas tax, total net investment, operating cost, and EOR cost and production data. Production data should be provided in Excel file. Sample production data file is provided for download. Once all inputs are accepted, forecast results will be calculated and displayed on the screen.

47. EOR KB Economics – Test case 1
Download sample production data here

48. Wiki: EOR KB Wiki displays articles regarding EOR methods and practices. It displays the articles in alphabetical order. User can click on the article to view full version.

49. 3) Demonstration of the ES
USername:
Password: xxxxxx

50. Test case 1
Input data

51. Output

52. Output

53. Output

54. Test case 1 results Scenario
Taber
Steam
Combustion
Immiscible gas
Polymer flooding
ASP
70%
56%
51%
49%
48%
Dickson
57%
Coodlett
Polymer
Alkaline
Steamflooding
Miscible Gas
74%
71%
67%
64%
63%
60%
Chemical flooding: purple
Thermal recovery: red
Gas injection: light green
What can be drawn for the above table?
Option 1 is CEOR, Option 2 is Thermal, and option 3 is GEOR
For option to be adopted, check:
- Chemical effectiveness- Lab testing
- chemicals availability (shelfed or to be developed)
- continuous supply (locally or globally)
- cost of chemicals
Judge the above against the standard workflow including an economical analysis, if not suitable consider other screened options.

55. Chemical Flood

56. Test case 1
Input data

57. Output data

58. Polymer Flood

59. Test case 1
Input data

60. Output data

61. CO2 Miscible Flood

62. Test case 1
Input data

63. Output data

64. Steamflood

65. Test case 1
Input data

66. Input data cont’

67. Output data

68. Conclusion It is just a tool for a starting point
Not meant to substitute our existing processes and practices but complements them
Judgment is still has a great value
Far from complete and ‘Design’ elements have to be developed and incorporated.

69. Thanks an appreciation
Authors would like to express their great thanks and appreciation to Kuwait MoO, KOC and RPS KR for permitting to publish this work...