Yenny Christanti

US Patent:

7290615, Nov 6, 2007

Filed:

Sep 17, 2004

Appl. No.:

10/943577

Inventors:

Yenny Christanti - Houston TX, US
Diankui Fu - Missouri City TX, US
Jian Zhou - Sugar Land TX, US

Assignee:

Schlumberger Technology Corporation - Sugar Land TX

International Classification:

E21B 37/00

US Classification:

166312

Abstract:

Compositions are given that have high viscosities at one pH range and low viscosities at another pH range. Methods are given for using such compositions in oilfield treatments. In particular CT wellbore cleanout compositions and methods are given in which a viscous fluid is injected into a wellbore; the fluid entrains particles and carries them to the surface; the viscosity of the fluid is reduced by reducing or increasing the pH; the particles settle from the fluid; the viscosity of the fluid is increased by increasing or reducing the pH; and the fluid is re-injected into the wellbore. Suitable surfactants are anionic surfactants, or mixtures of surfactants containing anionic surfactants, that aggregate into three-dimensional structures that substantially increase the viscosity at high pH but not at low pH. Other suitable surfactants are cationic surfactants with co-surfactants that aggregate below a certain pH but not above.

US Patent:

7299870, Nov 27, 2007

Filed:

Dec 1, 2005

Appl. No.:

11/292029

Inventors:

Marieliz Garcia-Lopez De Victoria - Houston TX, US
Yenny Christanti - Houston TX, US
Golchehreh Salamat - Sugar Land TX, US
Zhijun Xiao - Sugar Land TX, US
Bernhard Lungwitz - Houston TX, US

Assignee:

Schlumberger Technology Corporation - Sugar Land TX

International Classification:

E21B 43/25

US Classification:

166279, 166282, 166307

Abstract:

A method is described for treating a subterranean formation with a low viscosity fluid system that contains a surfactant or mixture of surfactants that does not divert fluid flow in the formation, but that develops the ability to divert flow as the fluid flows through the formation. The fluid optionally contains a formation-dissolving agent. The fluid is used in matrix acidizing, acid fracturing, and diversion.

US Patent:

7703527, Apr 27, 2010

Filed:

Nov 26, 2007

Appl. No.:

11/944681

Inventors:

Philip F. Sullivan - Bellaire TX, US
Gary John Tustin - Sawston Cambridge, GB
Yenny Christanti - Houston TX, US
Gregory Kubala - Houston TX, US
Bruno Drochon - Missouri City TX, US
Trevor Lloyd Hughes - Cambridge, GB

Assignee:

Schlumberger Technology Corporation - Sugar Land TX

International Classification:

E21B 33/13
C09K 8/42

US Classification:

166300, 166292, 166387, 507209, 507266

Abstract:

A low viscosity wellbore polymer fluid gelling system comprising an aqueous medium and a water-in-water emulsion comprising a plurality of polymers or oligomers, including at least one removable polymer or oligomer, and at least one gelling polymer or oligomer, wherein said fluid has a low viscosity when injected, and the gelling polymer forms a gel downhole which has a storage modulus of at least about 60 Pa after the removable polymer is removed from the fluid. A method of isolating at least one zone of a subterranean formation penetrated by a wellbore includes the steps of preparing a water-in-water emulsion comprising a plurality of polymers or oligomers including at least one removable polymer or oligomer, and at least one gellable polymer or oligomer; and combining the water-in-water emulsion with an aqueous medium to prepare a low viscosity polymer fluid.

US Patent:

8030254, Oct 4, 2011

Filed:

Oct 6, 2009

Appl. No.:

12/574248

Inventors:

Alhad Phatak - Houston TX, US
Yenny Christanti - Houston TX, US
Carlos Abad - Richmond TX, US
Balkrishna Gadiyar - Katy TX, US

Assignee:

Schlumberger Technology Corporation - Sugar Land TX

International Classification:

C09K 8/60
C09K 8/68
E21B 43/16

US Classification:

507277, 1663051, 507203, 507209, 507211, 507219, 507271

Abstract:

A method includes providing a wellbore treatment fluid having a divalent brine and an amount of polymer and lowering a pH value of the treatment fluid. The method further includes retaining the treatment fluid at the lower pH value until the polymer achieves a primary hydration value. The method further includes adding a cross-linking agent and a cross-linking delay agent to the treatment fluid. The cross-linking agent includes zirconium and/or titanium, and the cross-linking delay agent is a polyol. The method further includes performing a wellbore treatment with the treatment fluid.

US Patent:

8517102, Aug 27, 2013

Filed:

Nov 26, 2008

Appl. No.:

12/738853

Inventors:

Philip Sullivan - Bellaire TX, US
Gary Tustin - Sawston, GB
Yenny Christanti - Houston TX, US
Gregory Kubala - Houston TX, US
Bruno Drochon - Cambridge, GB
Trevor Hughes - Cambridge, GB

Assignee:

Schlumberger Technology Corporation - Sugar Land TX

International Classification:

E21B 43/22

US Classification:

166300, 166279, 166292, 1663051

Abstract:

A thickened aqueous composition is delivered to a subterranean location accessible via a wellbore by steps of i. providing a biphasic aqueous mixture comprising two aqueous solutions which, at surface temperature and pressure, are able to co-exist as separate aqueous phases in contact with each other, ii. pumping said biphasic aqueous system down the wellbore to the subterranean location, and iii. converting the biphasic mixture below ground so that its phases combine into a single aqueous phase which is more viscous than the biphasic mixture. The two phases of the aqueous biphasic mixture contain dissolved solutes which segregate between the two phases such that at least one first solute is present at a greater concentration in the first aqueous phase than in the second aqueous phase while at least one second solute is present at a greater concentration in the second aqueous phase than in the first aqueous phase. The solute in the first phase may be a thickening polymer or other thickening material such as viscoelastic surfactant. The solute in the second phase may be a different polymer, surfactant or salt.

US Patent:

8579029, Nov 12, 2013

Filed:

Dec 21, 2009

Appl. No.:

12/643431

Inventors:

Carlos Abad - Aberdeen, GB
Yenny Christanti - Houston TX, US
Syed Ali - Sugar Land TX, US
Balkrishna Gadiyar - Katy TX, US
Brent Busby - Richmond TX, US

Assignee:

Schlumberger Technology Corporation - Sugar Land TX

International Classification:

E21B 33/138
E21B 43/04
E21B 43/26
E21B 43/27
C09K 8/60

US Classification:

166278, 166281, 166282, 166283, 166294, 1663051, 1663082, 507234, 507251

Abstract:

A method includes providing a treatment fluid that is a viscous fluid. The viscous fluid may be greater than 0. 01 Pa-s, greater than 0. 1 Pa-s, and/or a cross-linked polymer based fluid. The method further includes determining a fines migration composition soluble in an aqueous phase of the treatment fluid that is compatible with the treatment fluid, and that interacts to secure fines in an earth formation intersecting a wellbore within a fines reaction time. The method further includes adding an amount of the fines migration composition to the treatment fluid, and treating the earth formation with the treatment fluid. The method includes leaking off a portion of the treatment fluid into the earth formation, and providing a residence time of the leaked off portion of the treatment fluid in the earth formation, where the residence time meets or exceeds the fines reaction time.

US Patent:

8044000, Oct 25, 2011

Filed:

Jul 2, 2008

Appl. No.:

12/166774

Inventors:

Philip F. Sullivan - Bellaire TX, US
Gary John Tustin - Sawston, GB
Yenny Christanti - Houston TX, US
Gregory Kubala - Houston TX, US
Bruno Drochon - Houston TX, US
Yiyan Chen - Sugar Land TX, US
Marie Noelle Dessinges - Paris, FR
Paul R. Howard - Sugar Land TX, US

Assignee:

Schlumberger Technology Corporation - Sugar Land TX

International Classification:

C09K 8/90

US Classification:

507214, 507211, 507215, 507216, 507217, 507225, 507244, 507261, 507263, 507265, 507269, 1663051

Abstract:

This invention relates to compositions and methods for treating subterranean formations, in particular, oilfield stimulation compositions and methods using water-in-water polymer emulsions to uniformly dissolve a rheologically active polymer, such as a thickener or friction reducer, in the treatment fluid. The emulsions have a low viscosity and are easily pumped for mixing into a treatment fluid, where upon dilution with an aqueous medium, the polymer is easily hydrated without forming fish-eyes. The partitioning agent in the water-in-water emulsion does not generally affect the rheology of the treatment fluid. The invention also relates to further processing of the emulsion by wet grinding, high shear mixing and/or heating to enhance the hydration rate in the preparation of the well treatment fluid.

US Patent:

20050107265, May 19, 2005

Filed:

Nov 13, 2003

Appl. No.:

10/707011

Inventors:

Philip Sullivan - Bellaire TX, US
Yenny Christanti - Houston TX, US
Isabelle Couillet - Cambridge, GB
Stephen Davies - Sugar Land TX, US
Trevor Hughes - Cambridge, GB
Alexander Wilson - Cambridge, GB

Assignee:

SCHLUMBERGER TECHNOLOGY CORP. - Sugar Land TX

International Classification:

E21B043/00

US Classification:

507271000

Abstract:

It is proposed a method of treating a subterranean formation including providing a suspension of colloidal particles prior to the injection of a treating fluid based on an aqueous fluid comprising a thickening amount of a viscoelastic surfactant. The colloidal particles help to reduce fluid losses into the formation. According to a second embodiment, the treating fluid includes a hydrophobically-modified polymer, said hydrophobically-modified polymer being present at a concentration between approximately its overlap concentration c* and approximately its entanglement concentration c. The method is particularly useful for fracturing operation in medium to high permeability formation.