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

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

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

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

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.

EOR screening

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

Conventional screening 1984 USA DOE-NPC- 1986 Goodlett 1997 Taber et al. Papers 2010 Dicxson

Advanced screening

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!.

U.S. DOE 1984 Screening Criteria

(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.

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.

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.

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

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.

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.

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.

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.

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.

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.

Screening Examples EOR Screen: Duri (Indonesia) k 750-1500 md Tres 100 F Φ 0.36 o at Tres 160 cp So 0.70 oil gravity 23 API depth 600 ft water salinity 1500 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

Screening Examples EOR Screen: Prudhoe Bay (Alaska) k 400 md Tres 210 F  0.22 o at Tres 1 cp So 0.50 oil gravity 27 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 (3000-3500 psi MMP) Polymer Flood: high Tres M-P Flood: high Tres

Radar plot - prioritization

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 189-205.

Depth limitation

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.

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

Home-Map-Technical screening-Wiki-Economic

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

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

This tool calculates according to Taber 1997, Dickson et al This tool calculates according to Taber 1997, Dickson et al. 2010, Goodlett et al. 1986 papers.

Sample case

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

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

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.

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

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.

3) Demonstration of the ES http://epimtest:8090/Home/Index USername: eorkb@kockw.com Password: xxxxxx

Test case 1 Input data

Output

Output

Output

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.

Chemical Flood

Test case 1 Input data

Output data

Polymer Flood

Test case 1 Input data

Output data

CO2 Miscible Flood

Test case 1 Input data

Output data

Steamflood

Test case 1 Input data

Input data cont’

Output data

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.

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...