BrightWater is a gel treatment polymer flooding in which a tightly bounded, thermally activated particle injected as a dilute slug which flows with the water and pops open deep in the reservoir and blocks the swept zones under the effect of high temperature. Its aim is to achieve more efficient sweep of the oil to the producing wells causing flow diversion by swelling and agglomerating of micro gel particles in the injection water.

1. BrightWater®
Presented by : Ahmed KamalKhalil

2. Contents
1.
Introduction-Traditional PF vs Gel Treatment PF
2.
What is BrightWater ?
3.
Mechanism
4.
Design Process of BW project-Laboratory Work
5.
Advantages of using BW-Why to use BW over traditional polymer flooding
6.
Candidate Reservoirs for BW
7.
History and Field Trails using BW.
8.
References

3. Introduction
Traditional PF vs Gel Treatment PF

4. Introduction
▪
Serightet al. (1994) classified polymer techniques into two groups:

Traditional polymer flooding

Gel treatments for conformance control

5. Traditional PF vsGel Treatment PF

Traditional Polymer Flooding
▪
In a traditional polymer flood, the injected polymer solution is designed to penetrate as far as possible into the poorly swept zones.

Gel Treatment (PPG, TAP, PH-sensitive Gels)
▪
In a gel treatment, the injected gel solution is designed to maximize its penetration into the high permeable channels while minimizing its penetration into less permeable zones saturated with oil (Serightet al., 1994).

6. Poor Reservoir Sweep Efficiency

7. BrightWater can help to improve sweep efficiency

8. What is BrightWater?

9. What is BrightWater ?

BrightWaterisageltreatmentpolymerfloodinginwhichatightlybounded,thermallyactivatedparticleinjectedasadiluteslugwhichflowswiththewaterandpopsopendeepinthereservoirandblocksthesweptzonesundertheeffectofhightemperature.Itsaimistoachievemoreefficientsweepoftheoiltotheproducingwellscausingflowdiversionbyswellingandagglomeratingofmicrogelparticlesintheinjectionwater.

10. What is BrightWater ?
BrightWatermaterial:atightlybounded,thermallyactivatedparticleinjectedasadiluteslugwhichflowswiththewaterandpopsopendeepinthereservoirandblocksthesweptzonesundertheeffectofhightemperature.
▪
Gel treatments can be classified into two groups:
1.
in-situ gels
2.
preformed particle gels

11. In-situ gel technology
▪
It involves injecting a mixture of polymer and crosslinker(called gelant) together or separately by slugs. Then a crosslinking reaction occurs by a specific trigger to generate gels in-situ, (Bai et al., 2007; Zhang et al., 2011).
▪
Traditionally, in-situ gels have been used for matrix treatments because gelantshave small viscosity to propagate through a matrix (Serightet al., 2003; Zhang et al., 2010).
What is BrightWater ?

12. Performed gels
▪
They are formed at the surface and no gelation takes place in the reservoir. Since gels usually have a single component when they are injected, they are less sensitive to physical and chemical properties of the reservoir (Bai et al. 2007).
▪
Traditionally, performed gels have been used for fractures or high-permeable channels.
What is BrightWater ?

13. Mechanism

14. Mechanism
▪
The particle consists of highly crosslinkedsulfonate- containing polyacrilamidemicroparticles(0.1-3 microns) constrained by both permanent and reversible crosslinks.

As it heats up, the reversible crosslinkerbreaks by hydrolysis and particles begin to expand in size and volume.

15. Mechanism -cont’d

Inactive particles are supplied in a constrained state – called “kernel” particle. After reaching the temperature front, the kernels are able to absorb surrounding water and expand up to 10 times their original size – subsequently being called “popcorn” for convenience (H. Frampton et al., 2004; J. Pritchett et al.,2003).

So the main particle diameter should be less than one tenth of the mean pore throat.

17. The effect of Temperature on BW particles
Warmth
0.1 to 1 micron
1 to 10 microns

18. BrightWater particles after and before activation
A polymer particle which is able to propagatethroughrock pores without injectivity loss
Under the influence of heat the particle expandsto a size which can block rock pore throats.
Before ExpansionScale bar is 500 nanometers
After Expansion
Scale bar is 5000 nanometers
This magnification is 10x greater than this one

19. Followed Steps to design a Bright Water project
Design Process of BW project

20. Laboratory Work

Bottle Tests:
The aim is to monitor polymer activation speed at given temperature and PH and to calibrate viscosity measurements.

Slim Tube Test:
The aim is to measure development of resistance factor versus time at different temperatures and polymer concentrations.

Core test:
The aim is to measure development of resistance factor condition close to reservoir conditions ( reservoir rock, reservoir temperature )

21. Process
▪
Optimum Treatment Size
The rule of thumb provided by Nalco, relates amount of polymer to the thief zone effective pore volume to be blocked. The recommendation is to use treatment size of 3% of the effective thief zone pore volume.
Typical polymer concentration are 1.5% -1.7% as supply concentration

22. Process
▪
Optimum Rate during Polymer Injection
The higher the injection rate, the more diversion will happen and proportionally less water would go into the high permeability zone than at lower rates. Hence lower initial injection rate leads to better treatment efficiency .

23. Process
▪
Optimum BW Placement
It was found that the best placement would be around 2/3rdof the way between producer and injector.

24. Advantages of Using Bright Water
Why to use BW over traditional polymer flooding

25. Traditional PF vsGel Treatment PF

Why to use BW over traditional polymer flooding
there are some technical issues associated with traditional polymer flooding :
1-InjectivityProblems
Polymer solutions have high viscosity and require a high pressure drop in order to inject them at a desired rate. This causes injectivityproblems and may result in artificially induced fractures near the wellbore region.

26. Traditional PF vsGel Treatment PF

Why to use BW over traditional polymer flooding
2-Shear-thinning Behavior
As polymer solution enters the formation, its shear rate rapidly falls. As a result, its viscosity starts to increase and a viscous bank can be formed in the vicinity of the wellbore.

27. Traditional PF vsGel Treatment PF

Why to use BW over traditional polymer flooding
3-Adsorption and retention
They also require large volumes of polymers to compensate for adsorption and retention (Sorbie, 1991; Pritchett et al., 2003).

28. Advantages of Using BrightWater

BrightWater material is NOT a classic viscous polymer

During injection it has viscosity very close to water

Reduces water flow into thief zones

Reduces costly water production

It cannot be damaged by shear during injection

It is not active initially

Totally different from conventional gel jobs.

No CAPEX –Simple to deploy

29. Difference between BW and Polymer
BWClassic polymer floodClassic WSO polymer gelFunctionflow diverting agentA pusher, mobility controlflow diverting agentTreatment fluidwater likeviscous fluidgelShear degradingNOYesYesInjectivityLike waterLowLowMechanism of EORExpand WF reachable zones Mobility controlTreatment volumesmalllargesmallSet up zonesFar away from injectornear ImplementationBullheadIsolationMatrix rockYesYesFracturesNoYes

30. Characteristics of good Candidate Reservoirs

31. Characteristics of good Candidate Reservoirs

32. The characteristics of BrightWater Particles

Theinjectedsub-micronparticlesareinert

Theygivevirtuallynoviscosityoradsorption.

Theyarefarsmallerthantheporestheymovethrough.

Theexpandedparticlesaresticky

Theyhaveincreasedsolutionviscosity,showingtheynowinteractwitheachother.

Theyacttorestrictwaterflowrateinthereservoir.

Therestrictioncanbepermanentshowingtheyareinteractingwiththeporousrock

33. History and Field Trails Using BW

34. History and Field Trails Using BW

Minas, Indonesia (Chevron, 2001)

Arbroath, North Sea, UK (BP, 2002)

Milne Point and Prudhoe Bay,Alaska, USA (BP, several, 2004-5)

Strathspeyfield, North Sea, UK (Chevron, 2006)

Argentina (several, 2006)

Pakistan (BP, 2006-7)

Alaska (several, 2007)

35. References

36. References
▪
Simulation of Thermally Active and pH-Sensitive Polymers for Conformance Control By Ulan Onbergenov
▪
BrightWater®–A Step Change in Sweep Improvement by NALCO.
▪
El Borma–Bright Water : a tertiary Method fotEOR for a mature Field, SPE 136140, F. Ghaddab, K kaddour, and M. Tesconi, 2010.
▪
Brightwater Trial in SalemaField ( Campos basin, Brazil), SPE 131299, Bruno Roussennac, 2010.
▪
Bright Water in a Nutshell a Pushing Reservoir Limits Technology Project, Harry Frampton, Andrew Cockin,BP Mar 2005

37. References
▪
Evaluating tertiary water based EOR methods on the Veslefrikkfield, with emphasis on analyzing sodium silicate injection by numerical simulation by BeateHansen, April 2009.
▪
Improved Oil Recovery using BrightWaterinjection, TPG-4851 GullfaksVillage, 2010.
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Bright Water, Nanotechnology, Extended Screening Criteria to Rank Well Patterns, Tiorco, Nalco and StepanCompany, 2012.
▪
Offshore field experience with BrightWater, Chevron Upstream Europe, Nancy Lugo, Jan 2010.
▪
Sydansk, R.D., Xiong, Y., Al-Dhafeeri, A., Schrader, R.J., and Seright, R.S. 2005.
▪
More than 12 Years’ Experience with a Successful Conformance Control Polymer-Gels Technology. SPE Prod. Fac. 2005.