1. Microgel Technology for Water Shutoff Applications Alain Zaitoun, Poweltec Guido Poggesi, REP WorkShop EOR, IAPG, Neuquen, 3-5 November 2010

2. Outline What is Microgel? Field case gas storage well
Water Shutoff basics
Field case gas storage well
Field cases heavy oil horizontal wells
Conclusions/Perspectives

3. New Microgel Technology
POWELTEC
With new microgel technology, chemistry, thickness and consistency of polymeric species can be modified to fit with actual reservoir conditions
dH  2.0 mm
dH  0.3 mm
Small microgel
Linear polymer
Microgel A
Microgel B
Linear chain

4. Microgel Tecnology = Where we are today
Microgel lots size 0.3 – 1.0 – 2.0 µm
Broad permeability range ( mD)
Commercially available under emulsion and powder forms
High temperature stability (up to 165°C)
High shear stability ( sec-1)
High chemical stability (CO2, H2S, high salinity)
Environmentally friendly (PLONOR N. Sea yellow list)
Efficient in WSO and Sand Control applications

5. Several Microgel products proposed today
“Brightwater” (Popping microgel)
“Colloidal Dispersion Gels” (CDG)
“SMG” (Small calibrated microgels)
“PPG” (Preformed Particle Gels to plug thief zones)
More used for Conformance Injection well treatments (except SMG)

6. Water Shutoff

7. Principe of WSO by RPM Polymers
Oil
Water
Low k
High K
Two-layer model
Swollen or
weakly
X-linked polymer

8. Modification of Relative Permeability
PRINCIPLE OF RPM TREATMENTS
Modification of Relative Permeability
by Polymer Adsorption
(Sor)
(Swi)
Adsorbed polymer or microgels
RRF=10
before polymer
after polymer

9. POWELTEC
Example of integrated study: Water Shutoff in a Gas storage well Cerville (GDF) (SPE )

10. Model construction

12. WSO GDF Cerville: Main outcomes from integrated study
Treatment design by lab and reservoir simulation study
Optimal volume = 50 m3
Water expected strongly reduced (Factor 3)
Pressure constraints during microgel injection is expected to be
the sensitive parameter for operational issues (verified in field)
Results
Treatment successful
Well behavior in good agreement with simul. forecasts

13. Effect of Microgel WSO treatment on gas well
Water Gas Ratio
Microgel Treatment

14. Effect of Microgel WSO treatment on gas well

15. Microgel Treatment of gas well= Sand Control
Sand production before treatment
Sand production after treatment
Microgel treatment in well X0
Measurements made by G. RIGOLLET-GOUSSU & M.G. GROUGON

16. Treatment Example of successfull WSO treatment:
Pelican Lake Horizontal Well 11-15A (Canada)
100
200
300
400
500
600
700
800
900
1000
juil-85
avr-88
juin-88
oct-88
avr-89
juin-89
oct-89
avr-90
juin-90
oct-90
avr-91
juin-91
0 %
10 %
20 %
30 %
40 %
50 %
60 %
70 %
80 %
90 %
100 %
Water
Oil
Water Cut
Year 1
Year 2
Year 3
Year 4
Monthly Production (m3)
Treatment

17. A successful WSO treatment in horizontal well (Canada)
1000
2000
3000
4000
5000
6000
7000
Cumulated Water Production (m3)
Sand
cleaning
Incremental
oil
RPM treatment
Cumulated Oil Production (m3)

18. POWELTEC
Example of integrated study: Water Shutoff in a Heavy-Oil Horizontal Well with Bottom Aquifer (Oman)

19. Candidate Well data High-permeability sandstone formation
Oil viscosity = 200 cP, Temperature= 50°C, Salinity= 6 g/L TDS
Horizontal well Open hole + screen 400 m long
High water cut production (98%), bottom active aquifer
Pumping Gross Production = 300 m3/d
Strategy
Reservoir simulation to optimize WSO treatment
Bullhead injection Microgel + Gel (RPM products)

20. Model construction and Polymer input data
Near-wellbore reservoir model
Coreflood data

21. Water rise in the wellbore
History matching
History matching
Water rise in the wellbore

22. Polymer WSO treatment

23. WSO performances forecasts from reservoir simulations

24. Field Results in good agreement with predictions

25. Conclusions/Perspectives
Microgels have great applications in WSO/Conformance
Higher stability than conventional polymers
Production well WSO by Microgels RPM attractive
Easy option, low risk, low cost, quick payout
Applicable in both oil and gas wells
Bullhead injection in most cases easy handling
Sand control effects can be also obtained