Optimal surfactant design for recovered hydrocarbon enhancement

Patent metadata

Field	Value
Publication number	US-9657565-B2
Application number	US-201414889091-A
Country	US
Kind code	B2
Filing date	Dec 31, 2014
Priority date	Dec 31, 2014
Publication date	May 23, 2017
Grant date	May 23, 2017

Abstract

Methods including the step of producing a bulk fluid from a subterranean formation, the bulk fluid comprising at least water and a hydrocarbon. The bulk fluid is then sampled to form at least one sampled fluid. Next, constituent parameters of the sampled fluid are determined using the hydrophilic-lipophilic deviation (HLD) model. The constituent parameters include the salinity (S) of the sampled fluid, the salinity constant (b); the equivalent alkane carbon number for the hydrocarbon in the sampled fluid (EACN); T is temperature of the sampled fluid; the characteristic curvature for an ionic surfactant composition (c c ) or for a nonionic surfactant composition (c cn ); the surfactant temperature constant for the ionic surfactant composition (α T ) or for a nonionic surfactant composition (c T ). Also determining an optimal surfactant or optimal surfactant blend to achieve an oil-water separation morphological phase distribution of the sampled fluid.

First claim

The invention claimed is:

1. A method comprising:
producing a bulk fluid from a subterranean formation, the bulk produced fluid comprising at least water and a hydrocarbon;
sampling a portion of the produced bulk fluid, thereby forming at least one sampled fluid;
determining constituent parameters of the sampled fluid using a hydrophilic-lipophilic deviation (HLD) model according to Equation A for an ionic surfactant composition or Equation B for a nonionic surfactant composition:
HLD= ln ( S )− k *EACN+ c c −α T ( T− 25° C.)  Equation A,

HLD= b ( S )− k *EACN+ c cn −c T ( T− 25° C.)  Equation B,

where S is salinity of the sampled fluid; b is a salinity constant; EACN is equivalent alkane carbon number for the hydrocarbon in the sampled fluid; T is temperature of the sampled fluid; c c is characteristic curvature for the ionic surfactant composition; c cn is characteristic curvature for the nonionic surfactant composition; α T is a surfactant temperature constant for the ionic surfactant composition; and c T is a surfactant temperature constant for the nonionic surfactant composition;

determining an optimal surfactant or optimal surfactant blend to achieve an oil-water separation morphological phase distribution of the sampled fluid according to Equation C:
min W 1 ·HLD 2 +W 2 (ρ− ρ ) 2 +W 3 (μ− μ ) 2 +W 4 ·cost+ W 5 ·uncertainty+ W 6 ·HSE+ W 7 ·experiment_cost+ W 8 ·robustness   Equation C,

where W is a user defined weighting factor, ρ is density of the optimal surfactant or the optimal surfactant blend, μ is viscosity of the optimal surfactant or the optimal surfactant blend, cost is combined material cost and transportation cost of the optimal surfactant or the optimal surfactant blend, HSE is a health, safety, and environmental risk rating value of the optimal surfactant or the optimal surfactant blend, experiment_cost represents the monetary cost of determining the properties of the ionic surfactant composition or nonionic surfactant composition according to Equation A or Equation B, robustness represents the ability of the optimal surfactant or surfactant blend to maintain steady HLD in a surrounding environment, and uncertainty is a non-negative parameter determined according to Equation D for an ionic optimal surfactant or ionic surfactant in the optimal surfactant blend or Equation E for a nonionic optimal surfactant or nonionic surfactant in the optimal surfactant blend:

uncertaintly
ionic

=

S
2

⁢

∑

i
=
1

N

⁢

c
i
2

·

σ

l
⁢

⁢

n
⁡

(
S
)

+

EACN
2

⁢

∑

i
=
1

N

⁢

c
i
2

·

σ

k
i

+

∑

i
=
1

N

⁢

c
i
2

·

σ

c
,
i

+

(

T
-

25
⁢
°
⁢

⁢

C
.

)

2

⁢

∑

i
=
1

N

⁢

c
i
2

·

Assignees

• Halliburton Energy Services Inc

Inventors

• Natali Sanja
• Dykstra Jason D
• Sun Zhijie
• Xue Yuzhen

Classifications

• G01N33/241

  for hydrocarbon content · CPC title

• E21B49/08 Primary

  Obtaining fluid samples or testing fluids, in boreholes or wells · CPC title

• G01N33/2823

  Raw oil, drilling fluid or polyphasic mixtures · CPC title

• B01D17/047

  with separation aids · CPC title

• C09K8/602 Primary

  containing surfactants · CPC title