U.S. patent application number 17/080922 was filed with the patent office on 2021-02-11 for foaming agent composition and method for removing hydrocarbon liquids from subterranean wells.
The applicant listed for this patent is Lonza Solutions AG. Invention is credited to Steven Colby, Kevin Janak.
Application Number | 20210040375 17/080922 |
Document ID | / |
Family ID | 1000005178266 |
Filed Date | 2021-02-11 |
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United States Patent
Application |
20210040375 |
Kind Code |
A1 |
Janak; Kevin ; et
al. |
February 11, 2021 |
Foaming Agent Composition and Method for Removing Hydrocarbon
Liquids from Subterranean Wells
Abstract
A composition containing a quaternary organosilane foaming agent
capable of foaming various liquids in order to remove the liquids
from subterranean wells is described. For instance, the composition
can be used to remove hydrocarbon condensate liquids from a gas
well or an oil well. Of particular advantage, the composition can
foam liquids containing substantial amounts of hydrocarbons.
Inventors: |
Janak; Kevin; (Ossining,
NY) ; Colby; Steven; (Atlanta, GA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Lonza Solutions AG |
Visp |
|
CH |
|
|
Family ID: |
1000005178266 |
Appl. No.: |
17/080922 |
Filed: |
October 27, 2020 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
15838464 |
Dec 12, 2017 |
10851282 |
|
|
17080922 |
|
|
|
|
62432894 |
Dec 12, 2016 |
|
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
C09K 8/86 20130101; C09K
8/703 20130101; C09K 8/035 20130101; C09K 2208/32 20130101; C07F
7/0834 20130101; C09K 8/94 20130101; E21B 43/16 20130101; C09K
2208/22 20130101; C09K 8/58 20130101; E21B 43/122 20130101; C09K
8/594 20130101; C09K 8/38 20130101; C09K 2208/20 20130101; E21B
43/34 20130101; C09K 2208/28 20130101 |
International
Class: |
C09K 8/38 20060101
C09K008/38; C07F 7/08 20060101 C07F007/08; E21B 43/12 20060101
E21B043/12; C09K 8/58 20060101 C09K008/58; E21B 43/16 20060101
E21B043/16; C09K 8/594 20060101 C09K008/594; C09K 8/86 20060101
C09K008/86; C09K 8/94 20060101 C09K008/94; C09K 8/035 20060101
C09K008/035; E21B 43/34 20060101 E21B043/34; C09K 8/70 20060101
C09K008/70 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 21, 2017 |
EP |
17161961.2 |
Claims
1. A composition for removing liquids from gas and oil wells,
comprising a foaming agent comprising a quaternary organosilane
having the following formula:
Y.sup.1Y.sup.2Y.sup.3Si-A-Q.sup.+R.sup.1R.sup.2R.sup.3X.sup.- (I)
wherein Y.sup.1, Y.sup.2, Y.sup.3 represent independently from each
other R or RO with each R representing independently from each
other a C.sub.1-4 alkyl group, A represents a C.sub.1-4 alkanediyl
or a C.sub.2-4 alkenediyl group, Q represents a nitrogen or
phosphorous atom, R.sup.1, R.sup.2 and R.sup.3 represent
independently from each other a C.sub.1-28 alkyl group with at
least one alkyl group having at least eight carbon atoms, and X
represents chloride, bromide, fluoride, iodide, acetate or
tosylate; a non-aqueous solvent combined with the quaternary
organosilane; and an additive contained in the composition, the
additive comprising a corrosion inhibitor, a scale inhibitor, a
hydrogen sulfide scavenger, or mixtures thereof.
2. The composition of claim 1, wherein the composition contains
less than about five percent by weight water.
3. The composition of claim 1, wherein composition is substantially
free of water.
4. The composition of claim 1, wherein the quaternary organosilane
comprises 3-(trimethoxysilyl) propyldimethyloctadecyl ammonium
chloride.
5. The composition of claim 1, wherein Y.sup.1, Y.sup.2, Y.sup.3
are each RO.
6. The composition of claim 1, wherein the non-aqueous solvent
comprises an organic solvent.
7. The composition of claim 5, wherein the organic solvent
comprises an alcohol, a benzene derivative, a ketone, an
ester-based solvent, a polar acetate, or mixtures thereof.
8. The composition of claim 1, wherein the non-aqueous solvent is
present in the composition in an amount of from about twenty-five
percent to about seventy-five percent by weight of the composition,
and the quaternary organosilane foaming agent is present in the
composition in an amount of from about twenty-five percent to about
seventy-five percent by weight of the composition.
9. The composition of claim 6, wherein the additive is present in
the composition in an amount less than about five percent by weight
of the composition.
10. The composition of claim 1, wherein the additive comprises the
hydrogen sulfide scavenger, and the hydrogen sulfide scavenger
comprises a glyoxal or comprises
1,3-dimethylol-5,5-dimethylhydantion.
11. The composition of claim 1, wherein the additive comprises the
corrosion inhibitor, and the corrosion inhibitor comprises an
amidoamine, a quaternary amine, an amide, a phosphate ester, or
mixtures thereof.
12. The composition of claim 1, wherein the additive comprises the
scale inhibitor, and the scale inhibitor comprises a phosphate, a
phosphate ester, a phosphoric acid, a phosphonate, a phosphonic
acid, a polyacrylamide, a salt of acrylamido-methyl propane
sulfonate/acrylic acid copolymer, a phosphinated maleic copolymer
(PHOS/MA), a salt of a polymaleic acid/acrylic
acid/acrylamido-methyl propane sulfonate terpolymer, or mixtures
thereof.
13. The composition of claim 1, wherein: the non-aqueous solvent is
present in the composition in an amount of from about twenty-five
percent to about seventy-five percent by weight of the composition;
the quaternary organosilane foaming agent is present in the
composition in an amount of from about twenty-five percent to about
seventy-five percent by weight of the composition; the additive is
present in the composition in an amount less than about five
percent by weight of the composition; and the composition contains
less than about five percent by weight water.
14. The composition of claim 13, wherein the quaternary
organosilane comprises 3-(trimethoxysilyl) propyldimethyloctadecyl
ammonium chloride.
15. The composition of claim 13, wherein the non-aqueous solvent
comprises an alcohol, a benzene derivative, a ketone, an
ester-based solvent, a polar acetate, or mixtures thereof.
16. The composition of claim 13, wherein the additive comprises the
hydrogen sulfide scavenger, and the hydrogen sulfide scavenger
comprises a glyoxal or comprises
1,3-dimethylol-5,5-dimethylhydantion.
17. The composition of claim 1, wherein the quaternary organosilane
foaming agent comprises non-polymeric quaternary organosilane.
18. The composition of claim 1, wherein the non-polymeric
quaternary organosilane has a molecular weight of less than about
900.
Description
RELATED APPLICATIONS
[0001] The present application is based on and claims priority to
U.S. Provisional Patent Application Ser. No. 62/432,894 filed on
Dec. 12, 2016, claims priority to U.S. Patent Application Ser. No.
15/838,464 filed on Dec. 12, 2017, and claims priority to European
Patent Application No. 17161961.2 filed on Mar. 21, 2017, which are
all incorporated herein by reference.
BACKGROUND
[0002] In order to harvest and collect natural gas, in one
embodiment, a bore is formed into the surface above a natural gas
reserve. When first completed, many natural gas wells have
sufficient reservoir pressure for flow to be established from the
reservoir to the surface. A typical problem of gas wells, however,
is that they often produce and accumulate liquids. The liquids may
comprise water or aqueous solutions and/or hydrocarbon compounds,
known as hydrocarbon condensates. As gas production continues, the
liquids have a tendency to accumulate within the well. As the
liquids accumulate the reservoir pressure declines and as pressure
declines, the velocity of the gases in the well decreases.
Eventually, the accumulated liquids can render the well
uneconomical and/or even stop production of the gas products. For
example, as the bottom well pressure approaches reservoir shut-end
pressure, gas flow stops and all liquid accumulates at the bottom
of the tubing that makes up the well.
[0003] Liquids such as hydrocarbon condensates can also build up
and cause problems in oil wells. The hydrocarbon liquids, for
instance, can create problems in the wells especially when the well
also contains natural gas or other hydrocarbon gases that are being
vented and/or collected.
[0004] One common approach to temporarily restoring flow is to vent
the well to the atmosphere, which is known as well "blow down."
Venting the well to the atmosphere, however, can result in a
significant amount of loss of the gas products being collected.
[0005] In view of the above, those skilled in the art have
attempted to devise different ways in order to remove the liquid
that accumulates within the natural gas and oil wells. For
instance, artificial lift methods that have been proposed in the
past in order to deliquify gas wells include pumping the liquids
using a suitable pumping device. For instance, those skilled in the
art have attempted to remove the liquids through cavity pumping,
submersible pumping, and hydraulic pumping. The use of pumps,
however, has many limitations. For instance, pumps have limited
head capacity. In addition, pumps cannot withstand many of the high
temperatures experienced within the wells. The use of pumps also
represents a significant capital cost and manpower requirement, and
can complicate the process.
[0006] Another method used in the past in order to remove liquids
within wells is to use plungers, such as tubing plungers or casing
plungers. The use of plungers, however, typically requires gas
production to stop while sufficient pressure builds to lift the
plunger to the surface of the well.
[0007] Those skilled in the art have also proposed placing soap
sticks or other foaming agents into a well that causes the liquid
portion to foam. The soap sticks, for instance, can include a
foaming agent such as an alkyl benzene sulfonate, an alcohol ether
sulfonate, alkylnapthalene sulfonate, alkyldiphenyloxide
disulfonate, and the like. Other foaming agents that have been
proposed for use in the past include alkyl quaternary ammonium
chlorides, dialkyl quaternary ammonium chlorides, alkyl amido
betaines, and alkyl imidazolines. In still another embodiment,
those skilled in the art have proposed using siloxane polymers as
foaming agents to remove liquids, primarily aqueous liquids from
gas and oil wells. Causing the unwanted liquids to foam, for
instance, greatly reduces the amount of pressure needed in order to
bring the liquid components to the surface. Thus, by foaming the
liquid, reservoir pressure can be used to remove the liquid.
[0008] Problems have been experienced in using foaming agents,
however. For instance, the above foaming agents are capable of
foaming water and aqueous solutions but are not capable of
sufficiently foaming hydrocarbons. Thus, the foaming agents are
only successful when the liquid in the well is comprised of
primarily water.
[0009] In view of the above, a need currently exists for a process
and method for removing liquids from a well, particularly natural
gas and oil wells. For instance, a need exists for a foaming
composition or foaming agent composition capable of foaming
hydrocarbon liquids, such as hydrocarbon condensates.
SUMMARY
[0010] In general, the present disclosure is directed to a foaming
or foamable composition capable of foaming liquids containing
substantial amounts of hydrocarbons, such as hydrocarbon
condensates. The composition is particularly well suited for use in
a method for removing liquids from a tubular structure, such as
subterranean wells. The tubular structure, for instance, may be
comprised of or attached to a gas or oil well, a well bore, or a
pipeline. The composition is capable of foaming a liquid that
contains one or more hydrocarbons in an amount greater than about
40% by weight, such as greater than 50% by weight, such as greater
than 60% by weight. The composition, in fact, is capable of foaming
a liquid comprised of only hydrocarbons. In accordance with the
present disclosure, the composition contains a quaternary
organosilane foaming agent.
[0011] For example, in one embodiment, the present disclosure is
directed to a method for removing a liquid from a tubular structure
which includes a step of adding a composition to a liquid contained
in the tubular structure. The composition comprises a foaming
agent, and particularly a quaternary organosilane. After the
composition is added to the liquid, a foamed liquid is formed
within the tubular structure. More particularly, the composition is
combined with the liquid in a manner that causes the liquid to form
a foam, such as through agitation. The liquid can primarily
comprise hydrocarbons alone or in combination with other liquids
such as water. Once formed into a foam, the foamed liquid is
brought to the surface of the tubular structure such as the gas or
oil well. At the surface, the foam dissipates and the resulting
liquid, which may also be combined with gases, can be fed to a
separator. The separator can comprise a pressure vessel for
separating the entering fluid into gaseous and liquid components.
The liquid components can be further separated into a hydrocarbon
component and a water component.
[0012] In one embodiment, the tubular structure comprises a gas or
oil well that includes a pressurized gas. The reservoir gas
pressure within the tubular structure not only assists in forming
the foam but also can be used to remove the foamed liquid from the
tubular structure after the foam is formed.
[0013] In one embodiment the quaternary organosilane can have the
following formula (I):
Y.sup.1Y.sup.2Y.sup.3Si-A-Q.sup.+R.sup.1R.sup.2R.sup.3x.sup.-
(I)
[0014] wherein:
[0015] Y.sup.1,Y.sup.2, Y.sup.3 represent independently from each
other R or RO wherein each R represents independently from each
other a C.sub.1-4 alkyl group;
[0016] A represents a C.sub.1-4 alkanediyl or a C.sub.2-4
alkenediyl group
[0017] Q represents a nitrogen or phosphorous atom;
[0018] R.sup.1, R.sup.2 and R.sup.3 represent independently from
each other a C.sub.1-28 alkyl group wherein at least one alkyl
group has at least eight carbon atoms; and
[0019] X represents chloride, bromide, fluoride, iodide, acetate or
tosylate.
[0020] In a preferred embodiment, the quaternary organosilane can
have the following formula (II):
(RO).sub.3Si-A-Q.sup.+R.sup.1R.sup.2R.sup.3X.sup.- (II)
[0021] wherein
[0022] each R represents independently from each other a C.sub.1-4
alkyl group;
[0023] A represents a C.sub.1-4 alkanediyl or a C.sub.2-4
alkenediyl group
[0024] Q represents a nitrogen or phosphorous atom;
[0025] R.sup.1, R.sup.2 and R.sup.3 represent independently from
each other a C.sub.1-28 alkyl group wherein at least one alkyl
group has at least eight carbon atoms; and;
[0026] X.sup.- represents chloride, bromide, fluoride, iodide,
acetate or tosylate.
[0027] Preferably the quaternary organosilane comprises a halide
salt of a quaternary ammonium silane. More preferably the
quaternary organosilane is 3-(trimethoxysilyl)
propyldimethyloctadecyl ammonium chloride.
[0028] As shown above, silanes that may be used according to the
present disclosure, in one embodiment, only contain a single
silicon atom in the molecule and thus exclude siloxanes. The
non-polymeric silane compounds can generally have a molecular
weight of less than about 900, such as less than about 800, such as
less than about 700, such as less than about 600. The molecular
weight of the silane molecule is generally greater than about 50,
such as greater than about 100.
[0029] In one embodiment, in addition to the quaternary
organosilane foaming agent, the composition can contain a solvent,
preferably a non-aqueous solvent. When containing a non-aqueous
solvent, the composition can have a low water content prior to
contact with the liquid in the tubular structure. For example,
water can be contained in the composition in an amount less than
about 5% by weight, more preferably less than about 2% by weight,
most preferably in an amount less than about 1% by weight.
[0030] In general, any suitable non-aqueous solvent can be combined
with the quaternary organosilane as long as the solvent does not
interfere with the foaming properties of the quaternary
organosilane and is compatible with the liquid in the tubular
structure. For example, the non-aqueous solvent may be selected
from a group comprising an alcohol, a benzene derivative, a ketone
or an ester or from mixtures of two or more of the
aforementioned.
[0031] In one embodiment, the composition contains the non-aqueous
solvent in an amount from 25% to 75% by weight and contains the
quaternary organosilane foaming agent in an amount of from 75% to
25% by weight. In one embodiment, the composition is added to the
liquid in the tubular structure in an amount such that the
concentration of the quaternary organosilane in the resulting
mixture is from 250 ppm to 5000 ppm.
[0032] After the foamed liquid is removed from the tubular
structure, the foamed liquid can be further processed as desired.
In one embodiment, for instance, hydrocarbons contained in the
foamed liquid can be separated and reused.
[0033] The present disclosure is also directed to a composition for
removing liquids from gas and oil wells. The composition comprises
a quaternary organosilane as described above. In one embodiment,
the quaternary organosilane foaming agent as described above is
combined with a non-aqueous solvent. The composition can further
comprise one or more additives. For instance, the additives may
comprise a corrosion inhibitor, a scale inhibitor, and/or a
hydrogen sulfide scavenger. For instance, in one embodiment, the
foaming agent composition contains a hydrogen sulfide scavenger
that comprises glyoxal or 1,3-dimethylol-5,5-dimethylhydantion. In
one embodiment, the non-aqueous solvent comprises naphtha or an
aromatic petroleum distillate, such as a benzene derivative. For
instance, the solvent may be selected from naphtha, xylene, or
toluene or mixtures thereof.
[0034] Of particular advantage, the composition of the present
disclosure is not only well suited to forming a foam with a liquid
containing substantial amounts of one or more hydrocarbons, but
also produces a foam that dissipates relatively quickly. In this
manner, the composition is capable of quickly foaming a hydrocarbon
liquid in order to remove the liquid from a tubular structure and
also has a relatively short foam half-life allowing for easy
handling of the recovered liquid and separation of the hydrocarbons
from aqueous components after removal. For example, the composition
of the present disclosure can have a foam half-life in kerosene of
less than 180 seconds when the concentration of the quaternary
organosilane in kerosene is 1000 ppm on a weight basis. For
example, the foam can have a half-life of less than 120 seconds,
such as less than 90 seconds, such as less than 60 seconds. When
the concentration of the quaternary organosilane in kerosene is
1500 ppm on a weight basis, the composition can have a foam
half-life in kerosene of less than about 240 seconds, such as less
than about 180 seconds, such as less than about 120 seconds, such
as less than about 100 seconds.
[0035] Other features and aspects of the present disclosure are
discussed in greater detail below.
DETAILED DESCRIPTION
[0036] In this text the following meanings are used if not
otherwise stated.
[0037] The term "halogen" or "halide" means F, Cl, Br or I or
fluoride (F.sup.-), chloride (Cl.sup.-), bromide (Br.sup.-), or
iodide (I.sup.-).
[0038] The term "alkyl" refers to linear or branched alkyl;
preferably linear alkyl. The term alkane means a linear or branched
alkane.
[0039] The term "alkanediyl" as used herein, refers to divalent
saturated aliphatic group, with one or two saturated carbon atom(s)
as the point(s) of attachment, a linear or branched, cyclo, cyclic
or acyclic structure, no carbon-carbon double or triple bonds, and
no atoms other than carbon and hydrogen. The groups,
--CH.sub.2--(methylene), --CH.sub.2CH.sub.2--,
--CH.sub.2C(CH.sub.3).sub.2CH.sub.2--, and
--CH.sub.2CH.sub.2CH.sub.2-- are non-limiting examples of
alkanediyl groups.
[0040] The term "alkenediyl" as used herein, refers to a divalent
unsaturated aliphatic group, with two carbon atoms as points of
attachment, a linear or branched, cyclo, cyclic or acyclic
structure, at least one nonaromatic carbon-carbon double bond, no
carbon-carbon triple bonds, and no atoms other than carbon and
hydrogen. The groups, --CH.dbd.CH--,
--CH.dbd.C(CH.sub.3)CH.sub.2--, --CH.sub.2--CH.dbd.CH-CH.sub.2--,
--CH.dbd.CH-CH.sub.2--CH.sub.2-- and --CH.dbd.CHCH.sub.2-- are
non-limiting examples of alkenediyl groups.
[0041] The term "alcohol" as used herein, refers to any of a class
of organic compounds characterized by one or more hydroxyl (--OH)
groups attached to a carbon atom of an alkyl group (hydrocarbon
chain). The alcohol can be primary, secondary or tertiary.
[0042] In the following text "hydrocarbon" as used herein refers to
an organic compound consisting entirely of hydrogen and carbon.
Hydrocarbons may be aromatic hydrocarbons (arenes), alkanes,
alkenes, cycloalkanes and alkyne-based compounds. Hydrocarbons may
be saturated hydrocarbons (alkanes) composed entirely of single
bonds and are saturated with hydrogen. The general formula for
saturated hydrocarbons is C.sub.nH.sub.2n+2 (assuming noncyclic
structures). Hydrocarbons may be unsaturated hydrocarbons having
one or more double or triple bonds between carbon atoms such as
alkenes and alkynes as defined above. Hydrocarbons may be
cycloalkanes, which are hydrocarbons containing one or more carbon
rings to which hydrogen atoms are attached. Hydrocarbons may be
aromatic hydrocarbons, also known as arenes, are hydrocarbons that
have at least one aromatic ring. Hydrocarbons may be a liquid
hydrocarbon. The liquid hydrocarbon may be any type of liquid
hydrocarbon including, but not limited to, crude oil, heavy oil,
processed residual oil, bituminous oil, coker oils, coker gas oils,
fluid catalytic cracker feeds, gas oil, naphtha, fluid catalytic
cracking slurry, diesel fuel, fuel oil, jet fuel, gasoline, and
kerosene.
[0043] The term "a mixture thereof" as used herein, refers to a
mixture of two or more of the aforementioned compounds.
[0044] The term a "tubular structure" as used herein, refers to a
pipe through which a gas or oil can be transported. The tubular
structure, for example, can be a subterranean well. The tubular
structure may be comprised of or attached to a gas or oil well, a
well bore, or a pipeline.
[0045] The term "fluid" refers to a liquid, a gas, or mixtures
thereof.
[0046] It is to be understood by one of ordinary skill in the art
that the present discussion is a description of exemplary
embodiments only, and is not intended as limiting the broader
aspects of the present disclosure.
[0047] In general, the present disclosure is directed to a
composition and to a method for removing hydrocarbon liquids from
subterranean wells by foaming the hydrocarbon liquids within the
well. For example, in one embodiment, the composition is
particularly well suited for removing hydrocarbon liquids from gas
and oil wells. In accordance with the present disclosure, the
composition contains a quaternary organosilane foaming agent, such
as a halide salt of a quaternary ammonium silane.
[0048] The composition of the present disclosure offers various
benefits and advantages when attempting to remove hydrocarbon
liquids from tubular structures through foam formation. For
instance, the composition of the present disclosure is particularly
well suited to foaming liquids containing substantial amounts of
hydrocarbons, such as hydrocarbon condensates, that may accumulate
in oil and gas wells. For instance, in the past, problems have been
experienced in attempting to foam liquids in oil and gas wells when
the liquids contain less than about 80% water. The composition of
the present disclosure, on the other hand, can foam liquids
containing less than 80% water, such as less than 60% water, such
as less than 40% water, such as less than 20% water, such as less
than 10% water by weight. For example, the composition of the
present disclosure can foam liquids containing hydrocarbons in an
amount greater than about 20%, such as in an amount greater than
about 40%, such as in an amount greater than about 50%, such as in
an amount greater than about 60%, such as in an amount greater than
about 70%, such as in an amount greater than about 80%, such as
even in amounts greater than about 90% by weight. The composition,
in fact, can foam liquids that contain substantially no water (less
than about 5% by weight, such as less than 2% by weight, such as
less than about 1% by weight water,) and are made almost entirely
from hydrocarbon liquids.
[0049] In addition to being capable of foaming hydrocarbon liquids,
the composition of the present disclosure also rapidly produces
foam, and, in turn, produces a foam that also rapidly dissipates.
This provides various advantages and benefits when removing liquids
from tubular structures, such as oil and gas wells. For instance,
during the process, a foam rapidly develops that allows for liquids
in the well to rise and be removed from the well. The composition
also creates a foam that breaks at the well surface. By breaking at
the surface, the liquid collected from the well can be easily
handled and further processed. Dissipation of the foam, for
instance, allows for easy separation of the components contained in
the liquid. For instance, in one embodiment, any hydrocarbons
contained in the liquid can be separated from the remainder of the
liquid. For example, liquids removed from the well in accordance
with the present disclosure can be fed to a separator that
separates the liquids into a hydrocarbon component and an aqueous
component.
[0050] The composition of the present disclosure may comprise a
foaming agent, such as a quaternary organosilane, in combination
with a solvent. Preferably the solvent is a non-aqueous solvent.
The composition is particularly well suited for removing liquids
from tubular structures, such as gas wells, oil wells, or a
pipeline. In one embodiment, for instance, the composition can be
used to remove liquids from a gas well, such as a natural gas well.
In accordance with the present disclosure, the composition can be
added to the well continuously or in a batch wise manner. In one
embodiment, for instance, the composition can be continuously added
to the well using a string or capillary extending into the well
bore. Of particular advantage, the composition is well suited to
withstanding the temperatures and pressures that may exist within a
gas or oil well. When removing liquids from a well, the reservoir
gas pressure within the well can be used to assist in forming a
foam between the composition and a liquid contained in the well and
can also be used as the pressure needed in order to remove the
foamed liquid from the well.
[0051] In addition to gas wells, the composition of the present
disclosure can also be used to remove liquids, such as hydrocarbon
condensates, from oil wells. In some oil wells, sufficient
reservoir gas pressure exists capable of not only facilitating foam
formation but also sufficient to rise the foamed liquid to the top
of the well. In other embodiments, however, artificial gas pressure
can be introduced into the well for removing the foamed liquid. For
instance, an inert gas, such as nitrogen, can be pumped into the
well for facilitating foam formation and for providing sufficient
pressure to bring the foamed liquid to the surface.
[0052] Quaternary organosilanes have been found to be particularly
well suited for foaming liquids in accordance with the present
disclosure. Quaternary organosilanes are unique due to the presence
of a polar cationic nitrogen and a non-polar organic group, which
makes them amphiphilic in nature. Their cationic nature makes them
water soluble and/or dispersible, while the non-polar hydrocarbon
component makes them easily soluble and/or dispersible in non-polar
mixtures. Although unknown, it is believed that the amphiphilic
behavior of the quaternary organosilane compounds helps stabilize a
non-polar/polar interface such as a water condensate mixture,
thereby making quaternary organosilanes excellent foam
producers.
[0053] The quaternary organosilane composition, according to
certain embodiments of the present disclosure, may comprise one or
more quaternary organosilane compounds comprising at least one
alkoxy group. Preferably, the at least one alkoxy group comprises
ethylene glycol or polyethylene glycol functionality. The at least
one alkoxy group can comprise ethylene glycol or polyethylene
glycol functionality bonded to a silicon atom.
[0054] In certain embodiments, the one or more quaternary
organosilane compounds can have the following formula (I):
Y.sup.1Y.sup.2Y.sup.3Si-A-Q.sup.+R.sup.1R.sup.2R.sup.3X.sup.-
(I)
[0055] wherein:
[0056] Y.sup.1, Y.sup.2, Y.sup.3 represent independently from each
other R or RO wherein each R represents independently from each
other a C.sub.1-4 alkyl group;
[0057] A represents a C.sub.1-4 alkanediyl or a C.sub.2-4
alkenediyl group;
[0058] Q represents a nitrogen or phosphorous atom;
[0059] R.sup.1, R.sup.2 and R.sup.3 represent independently from
each other a C.sub.1-28 alkyl group wherein at least one alkyl
group has at least eight carbon atoms, 13 CH.sub.2C.sub.6H.sub.5,
--CH.sub.2CH.sub.2OH, --CH.sub.2OH, and
--(CH.sub.2)xNHC(O)R.sup.6wherein x is an integer of two to ten and
R.sup.6 is a C.sub.1-12-perfluoroalkyl group; and
[0060] X represents chloride, bromide, fluoride, iodide, acetate or
tosylate.
[0061] In one embodiment, the silanes are trialkoxysilyl compounds
having the general formula (II)
(RO).sub.3Si-A-Q.sup.+R.sup.1R.sup.2R.sup.3X.sup.- (II)
[0062] wherein
[0063] each R represents independently from each other a C.sub.1-4
alkyl group;
[0064] A represents a C.sub.1-4 alkanediyl or a C.sub.2-4
alkenediyl group;
[0065] Q represents a nitrogen or phosphorous atom;
[0066] R.sup.1, R.sup.2 and R.sup.3 represent independently from
each other a C.sub.1-28 alkyl group wherein at least one alkyl
group has at least eight carbon atoms; and;
[0067] X.sup.- represents chloride, bromide, fluoride, iodide,
acetate or tosylate.
Exemplary silanes for this disclosure are those silanes having the
formula
(CH.sub.3O).sub.3Si(CH.sub.2).sub.3N.sup..sym.(CH.sub.3).sub.2C.sub.18H.-
sub.37Cl-- and
(CH.sub.3O).sub.3Si(CH.sub.2).sub.3-N.sup..sym.CH.sub.3(C.sub.10H.sub.21-
).sub.2Cl--.
[0068] Specific silanes within the scope of the disclosure are
represented by the following:
##STR00001##
[0069] In one embodiment, the organosilane quaternary ammonium
compound for application in accordance with the method of the
present disclosure is 3-(trimethoxysilyl) propyldimethyloctadecyl
ammonium chloride of the formula
##STR00002##
[0070] As shown above, 3-(trimethoxysilyl) propyldimethyloctadecyl
ammonium chloride has an alkyl group attached to the nitrogen
having a carbon chain length of 18 carbon atoms. In certain
embodiments, this alkyl group can have a carbon chain length of at
least 8 carbon atoms, such as at least 12 carbon atoms, such as at
least 14 carbon atoms, such as at least 16 carbon atoms. The carbon
chain length of this alkyl group can be generally less than about
28 carbon atoms, such as less than about 22 carbon atoms.
[0071] The foaming agent, such as the organosilane quaternary
ammonium compound as described above, can be combined with a
solvent to form the foaming agent composition in accordance with
the present disclosure. Preferably the solvent is selected from a
non-aqueous solvent. More preferably the solvent can comprise an
organic solvent.
[0072] Suitable organic solvents should preferably not negatively
impact the stability of the quaternary organosilane compounds.
Suitable solvents are, but are not limited to, alcohols, naphtha,
benzene derivatives, ketones or esters, or mixtures of two or more
of the aforementioned. Preferably the organic solvents may include
at least one alcohol.
[0073] Examples of alcohols that can be used according to the
present invention are, but are not limited to methanol, ethanol,
isopropanol and glycols. Examples of glycols and derivatives
thereof that can be used are, but are not limited to, ethylene
glycol, propylene glycol, ethylene glycol monoethyl ether, ethylene
glycol monobutyl ether, ethylene glycol dibutyl ether, ethylene
glycol monoethyl ether acetate, ethylene glycol monohexyl ether
acetate, propylene glycol monoethyl ether, propylene glycol dibutyl
ether; the mono- and dialkylethers of diethylene glycol such as
diethylene glycol monoethyl ether, diethylene glycol dibutyl ether,
diethylene glycol diethyl ether, and diethylene glycol monobutyl
ether acetate.
[0074] In one embodiment, the solvent is selected from a group
comprising naphtha or an aromatic petroleum distillate, or mixtures
thereof. Preferably the solvent may comprise naphtha or benzene
derivatives. Examples include, but are not limited to, naphtha,
xylene, toluene or mixtures thereof.
[0075] Examples of ketones that can be used according to the
present invention are, but are not limited to, acetone,
acetophenone, butanone, cyclohexanone, ethyl isopropyl ketone,
diacetone, isophorone, methyl isobutyl ketone, methyl isopropyl
ketone, methylethyl ketone, methylamyl ketone, and 3-pentanone.
[0076] Examples of ester solvents that can be used according to the
present invention are, but are not limited to, preferably esters
and more preferably acetate esters. Preferably the solvent is
selected from, but not limited to, benzyl benzoate, more preferably
from butyl acetate, methyl acetate, ethyl acetate, n-propyl
acetate, isobutyl acetate, isoamyl acetate, isopropyl acetate,
n-butyl acetate, isobutyl acetate, amyl acetate, sec-butyl acetate,
tert-butyl acetate, ethyl acetoacetate, ethylene glycol monomethyl
ether acetate and ethylene glycol monoethyl ether acetate.
[0077] The solvent combined with the quaternary organosilane may
also comprise a mixture of any of the solvents described above. In
one embodiment, the solvent may comprise water. In one embodiment,
however, the foamable composition is substantially free of water
containing water in an amount less than about 5% by weight, such as
in an amount less than about 2% by weight, such as in an amount
less than about 1% by weight. In one embodiment, for instance, the
foaming agent composition does not contain water and is
water-free.
[0078] In one embodiment preferably, one or more solvents are
contained in the composition of the present disclosure in an amount
greater than about 25% by weight, such as in an amount greater than
about 40% by weight, such as in an amount greater than about 50% by
weight, such as in an amount greater than about 60% by weight, such
as in an amount greater than about 70% by weight, such as in an
amount greater than about 80% by weight, such as in an amount
greater than about 90% by weight, such as in an amount greater than
about 95% by weight. One or more solvents are preferably contained
in the composition in an amount less than about 98% by weight, such
as in an amount less than about 95% by weight, such as in an amount
less than about 90% by weight, such as in an amount less than about
80% by weight, such as in an amount less than about 70% by weight,
such as in an amount less than about 50% by weight.
[0079] Preferably the quaternary organosilane is present in the
composition in an amount generally greater than about 2% by weight,
such as in an amount greater than about 25% by weight, such as
greater than about 35% by weight, such as greater than about 45% by
weight, such as greater than about 55% by weight, such as greater
than about 65% by weight, such as even greater than about 70% by
weight. The quaternary organosilane is preferably present in the
foaming agent composition in an amount less than about 75% by
weight, such as in an amount less than about 65% by weight, such as
in an amount less than about 55% by weight, such as in an amount
less than about 45% by weight, such as in an amount less than about
35% by weight.
[0080] The composition may further comprise one or more oil field
additives selected from the group comprising corrosion inhibitors,
scale inhibitors, emulsifiers, water clarifiers, dispersants,
emulsion breakers, hydrogen sulfide scavengers, gas hydrate
inhibitors, biocides, pH modifiers, surfactants, synergistic
compounds, asphaltene inhibitors, paraffin inhibitors,
antioxidants, pour point depressants, viscosity modifiers, flow
back aids, friction reducers, or crosslinking agents. Unless
otherwise specified, these additives typically are less than 5%,
such as less than 2%, such as less than 1% by weight and generally
greater than about 0.01% by weight. Such additives can be
introduced into the well, wellbore or pipeline before, during or
after the introduction of the foaming agent composition, or can be
a component of said composition.
[0081] Suitable corrosion inhibitors include, but are not limited
to, amidoamines, quaternary amines, amides, and phosphate
esters.
[0082] Suitable scale inhibitors include, but are not limited to,
phosphates, phosphate esters, phosphoric acids, phosphonates,
phosphonic acids, polyacrylamides, salts of acrylamido-methyl
propane sulfonate/acrylic acid copolymer (AMPS/AA), phosphinated
maleic copolymer (PHOS/MA), and salts of a polymaleic acid/acrylic
acid/acrylamido-methyl propane sulfonate terpolymer (PMA/AMPS).
[0083] Suitable emulsifiers include, but are not limited to, salts
of carboxylic acids, products of acylation reactions between
carboxylic acids or carboxylic anhydrides and amines, and alkyl,
acyl and amide derivatives of saccharides (alkyl-saccharide
emulsifiers).
[0084] Suitable water clarifiers include, but are not limited to,
inorganic metal salts such as alum, aluminum chloride, and aluminum
chlorohydrate, or organic polymers such as acrylic acid based
polymers, acrylamide based polymers, polymerized amines,
alkanolamines, thiocarbamates, and cationic polymers such as
diallyldimethylammonium chloride (DADMAC).
[0085] Suitable dispersants include, but are not limited to,
aliphatic phosphonic acids with 2-50 carbons, such as hydroxyethyl
diphosphonic acid, and aminoalkyl phosphonic acids, e.g.
polyaminomethylene phosphonates with 2-10 N atoms e.g. each bearing
at least one methylene phosphonic acid group; examples of the
latter are ethylenediamine tetra(methylene phosphonate),
diethylenetriamine penta(methylene phosphonate) and the triamine-
and tetramine-polymethylene phosphonates with 2-4 methylene groups
between each N atom, at least 2 of the numbers of methylene groups
in each phosphonate being different. Other suitable dispersion
agents include lignin or derivatives of lignin such as
lignosulfonate and naphthalene sulfonic acid and derivatives.
[0086] Suitable emulsion breakers include, but are not limited to,
dodecylbenzylsulfonic acid (DDBSA), the sodium salt of xylene
sulfonic acid (NAXSA), epoxylated and propoxylated compounds,
anionic cationic and nonionic surfactants, and resins, such as
phenolic and epoxide resins.
[0087] Examples of hydrogen sulfide scavengers include, but are not
limited to, oxidants such as inorganic peroxides such as sodium
peroxide, or chlorine dioxide, aldehydes or dialdehydes, such as
C.sub.1-10 aldehydes, formaldehyde, glutaraldehyde, (meth)acrolein
or glyocxal), triazines such as monoethanol amine triazine, and
monomethylamine triazine and hydantoins such as
hydroxyalkylhydantoins, bis(hydroxyalkyl)hydantoins and
dialkylhydantoins where the alkyl group is a C.sub.1-6 alkyl
group.
[0088] Preferably the hydrogen scavenger is selected from a group
comprising glyoxal or bis(hydroxyalkyl)hydantoins. More preferably,
the hydrogen sulfide scavenger is
1,3-Bis(hydroxymethyl)-5,5-dimethylhydantoins also known as
1,3-dimethylol-5,5-dimethylhydantion (DMDMH).
[0089] Suitable gas hydrate inhibitors include, but are not limited
to, thermodynamic inhibitors (THI), kinetic inhibitors (KHI), and
anti-agglomerates (AA). Suitable thermodynamic inhibitors include,
but are not limited to, NaCl salt, KCl salt, C.sub.aCl.sub.2 salt,
MgCl.sub.2 salt, NaB.sub.2 salt, formate brines (e.g. potassium
formate), polyols (such as glucose, sucrose, fructose, maltose,
lactose, gluconate, monoethylene glycol, diethylene glycol,
triethylene glycol, mono-propylene glycol, dipropylene glycol,
tripropylene glycols, tetrapropylene glycol, monobutylene glycol,
dibutylene glycol, tributylene glycol, glycerol, diglycerol,
triglycerol, and sugar alcohols (e.g. sorbitol, mannitol),
methanol, propanol, ethanol, glycol ethers (such as
diethyleneglycol monomethyl ether, ethylene glycol monobutyl
ether), and alkyl or cyclic esters of alcohols (such as ethyl
lactate, butyl lactate, methylethyl benzoate). Suitable kinetic
inhibitors and anti-agglomerates include, but are not limited to,
polymers and copolymers, polysaccharides (such as
hydroxy-ethylcellulose (HEC), carboxymethylcellulose (CMC), starch,
starch derivatives, and xanthan), lactams (such as
polyvinylcaprolactam, polyvinyl lactam), pyrrolidones (such as
polyvinyl pyrrolidone of various molecular weights), surfactants
(such as fatty acid salts, ethoxylated alcohols, propoxylated
alcohols, sorbitan esters, ethoxylated sorbitan esters,
polyglycerol esters of fatty acids, alkyl glucosides, alkyl
polyglucosides, alkyl sulfates, alkyl sulfonates, alkyl ester
sulfonates, alkyl aromatic sulfonates, alkyl betaine, alkyl amido
betaines), hydrocarbon based dispersants (such as lignosulfonates,
iminodisuccinates, polyaspartates), amino acids, and proteins.
[0090] Any biocide suitable in oilfield operations may be used. A
biocide may be included in a composition in an amount of about 0.1
ppm to about 1000 ppm on a weight basis. Suitable biocides include,
but are not limited to, oxidizing and non-oxidizing biocides.
Suitable non-oxidizing biocides include, for example other
quaternary ammonium compounds (e.g., quaternary amine compounds and
cocodiamine), halogenated compounds (e.g., bronopol and
2-2-dibromo-3-nitrilopropionamide (DBNPA)), sulfur compounds (e.g.,
carbamates, and metronidazole), and quaternary phosphonium salts
(e.g., tetrakis(hydroxymethyl)phosphonium sulfate (THPS)). Suitable
oxidizing biocides include, for example, sodium hypochlorite,
trichloroisocyanuric acids, dichloroisocyanuric acid, calcium
hypochlorite, lithium hypochlorite, chlorinated hydantoins,
stabilized sodium hypobromite, activated sodium bromide, brominated
hydantoins, chlorine dioxide, ozone, and peroxides.
[0091] Suitable pH modifiers include, but are not limited to,
alkali hydroxides, alkali carbonates, alkali bicarbonates, alkaline
earth metal hydroxides, alkaline earth metal carbonates, alkaline
earth metal bicarbonates and mixtures or combinations thereof.
Exemplary pH modifiers include NaOH, KOH, Ca(OH).sub.2, CaO,
Na.sub.2CO.sub.3, KHCO.sub.3, K.sub.2CO.sub.3, NaHCO.sub.3, MgO,
and Mg(OH).sub.2.
[0092] Any antioxidant suitable in oilfield operations may be used.
Exemplary antioxidants include but are not limited to sulfites,
thiocyanates and thiosulfates. An antioxidant may be included in a
composition in an amount of about 1 ppm to about 1000 ppm on a
weight basis.
[0093] The composition may also comprise one or more additional
foaming agents such as an additional anionic surfactant, a cationic
surfactant, a nonionic surfactant, an amphoteric surfactant, or a
zwitterionic surfactant. Such additives can be introduced into the
well, wellbore or pipeline before, during or after the introduction
of quaternary organosilane composition.
[0094] As described above, the composition of the present
disclosure is combined with a liquid in order to cause the liquid
to foam. In one embodiment, the liquid is foamed in the presence of
other fluids in order to separate the liquid from the other fluids.
For instance, in one embodiment, the liquid can be contained in a
tubular structure comprising a gas well and the other fluid can
comprise natural gas. The amount of the composition added to the
liquid can depend upon numerous factors and circumstances. In one
embodiment, the composition is added to a liquid in an amount
sufficient for the quaternary organosilane to have a concentration
of at least about 250 ppm, such as at least about 500 ppm, such as
at least about 750 ppm, such as at least about 1000 ppm, such as at
least about 1500 ppm, such as at least about 2000 ppm, such as at
least about 3000 ppm, such as at least about 4000 ppm. The
concentration of the quaternary organosilane in the liquid is
generally less than about 10,000 ppm, such as less than about 5000
ppm, such as less than about 3000 ppm on a weight basis.
[0095] The present disclosure may be better understood with
reference to the following example.
EXAMPLE
[0096] A series of tests were conducted to determine the foaming
ability and foam stability of four foaming agents when combined
with a hydrocarbon liquid. Three of the foaming agents represent
various foaming agents that have been used in the past. The
conventional foaming agents were compared to a foaming agent in
accordance with the present disclosure.
[0097] The following example demonstrates the ability of
compositions made according to the present disclosure to foam a
hydrocarbon particularly kerosene. In this example, a composition
containing a quaternary organosilane in accordance with the present
disclosure was compared with compositions containing (1)
didecyldimethylammonium chloride, (2) a cocamine oxide surfactant,
and (3) an alkyl imidazoline surfactant, particularly a
coco-substituted imidazoline.
[0098] The following test procedure was used. The quaternary
organosilane composition and the other foaming agent compositions
were added to a one liter graduated cylinder containing 200 mL of
kerosene. Nitrogen was sparged into the kerosene in the graduated
cylinder via a glass diffusion stone at a rate of 56.6 L/hr (2
SCFH).
[0099] The quaternary organosilane composition and the other
foaming agents were added to the kerosene at a concentration of
between 250 ppm to 1500 ppm on a weight basis using a
micropipet.
[0100] The foam height represented the mL occupied by the foam
after the foam was formed. Foam height was observed for 5 minutes
or for the required time in order to meet maximum foam height. The
half-life represents the time it takes a foam having an initial
foam volume to decay by 50% of that original foam volume, e.g., if
the initial foam volume is 500 mL as measured in a 1000 mL
graduated cylinder, then the half-life is the time is takes for the
foam volume to reduce to a value of 250 mL
[0101] Foam half-life was measured at the time in which the foam
collapsed to half of its original volume. Testing was performed at
room temperature 22.degree. C. The materials used in the examples
are as follows:
TABLE-US-00001 Material Description Kerosene 100% Low odor Kerosene
(CAS 64742-47-8) Sample No. 1 72% 3-(trimethoxysilyl)
propyldimethyloctadecyl ammonium chloride (CAS 27668-52-6) and 28%
methanol Sample No. 2 80% Didecyldimethylammonium chloride (CAS
7173-51-5), 10% water and 10% ethanol Sample No. 3
N-alkyl(C.sub.12-C.sub.16) dimethylamine oxide containing primarily
cocamine oxide sold as Barlox .RTM. 12 by Lonza, Inc. Sample No. 4
Coco-substituted imidazoline sold as Amphoterge .RTM. K-2 by Lonza,
Inc.
[0102] Sample No. 1 above is a milky liquid with 72% active. A 10%
stock solution was used to dose the material into the kerosene at
the desired concentration. The 10% stock solution was produced by
combining 10% of Sample No. 1 by weight with 90% by weight
kerosene. Sample No. 1 was observed to dissolve fully to form a 10%
solution in kerosene. Sample No. 2 is known to have solubility in
kerosene of less than 1000 ppm. Sample No. 2 was dosed directly to
the foam cell kerosene sample. Sample Nos. 2 and 3 were also formed
into 10% by weight stock solutions in kerosene prior to being added
to the foam cell kerosene samples at the desired concentrations.
The following results were obtained:
TABLE-US-00002 A.I. Max Foam Foam Foam Material Dosage at Time
Height Half-Life Observation Kerosene -- 5 min 20 mL <2 sec Fast
breaking Alone foam Sample No. 1 250 ppm 5 min 15 mL <2 sec
Precipitation 500 ppm 2 min 80 mL <2 sec observed 5 min 30 mL
after sitting 750 ppm 1.5 min 755 mL <5 sec over night 2.5 min
280 mL 5 min 80 mL 1000 ppm 1.5 min 880 mL 60 sec 2.5 min 480 mL 5
min 230 mL 1500 ppm 1.5 min 980 mL 90 sec (max) Sample No. 2 250
ppm 5 min 25 mL <2 sec Slightly Hazy 500 ppm 5 min 25 mL
solution after 750 ppm 5 min 20 mL sitting 1000 ppm 5 min 20 mL
overnight 1500 ppm 5 min 25 mL Sample No. 3 0 ppm 5 min 10 mL <2
sec Fast breaking 250 ppm 5 min 10 mL <2 sec foam 500 ppm 5 min
10 mL <2 sec 750 ppm 5 min 10 mL <2 sec 1000 ppm 5 min 10 mL
<2 sec 1500 ppm 5 min 10 mL <2 sec Sample No. 4 0 ppm 5 min
10 mL <2 sec Fast breaking 250 ppm 5 min 10 mL <2 sec foam
500 ppm 5 min 10 mL <2 sec 750 ppm 5 min 10 mL <2 sec 1000
ppm 5 min 10 mL <2 sec 1500 ppm 5 min 10 mL <2 sec
[0103] Sample No. 1 appeared to be a self-dispersing composition in
kerosene in high concentrations. At 1500 ppm, the treated kerosene
was observed to contain a precipitate after sitting over night.
[0104] Although Sample No. 1 and Sample No. 2 are both quaternary
ammonium compounds, Sample No. 1 shows significantly higher foaming
performance in kerosene. Sample No. 1 had high foaming potential
when dosed at 750 to 1500 ppm in kerosene. The maximum foam height
was reached early (particularly at 1.5 minutes). In addition, the
foam of Sample No. 1 dispersed relatively quickly having a foam
half-life of 60 seconds at 1000 ppm and having a foam half-life of
90 seconds at 1500 ppm. This result is particularly advantageous.
For example, when combined with a hydrocarbon liquid in an oil or
gas well, the foaming agent of the present disclosure will rapidly
form a foam, allow the foamed hydrocarbon liquid to reach the
surface, and then the foam will rapidly disperse leaving a
hydrocarbon liquid product that can be easily handled and
processed.
[0105] In contrast, all of the other foaming agents (Sample No. 2,
Sample No. 3, and Sample No. 4) were not capable of forming any
substantial amounts of foam when combined with the kerosene under
the test conditions. Although the foaming agents of Sample No. 2,
Sample No. 3, and Sample No. 4 are capable of forming a foam when
combined with water, the foaming agents are not suited for foaming
hydrocarbon liquids.
[0106] These and other modifications and variations to the present
invention may be practiced by those of ordinary skill in the art,
without departing from the spirit and scope of the present
invention, which is more particularly set forth in the appended
claims. In addition, it should be understood that aspects of the
various embodiments may be interchanged either in whole or in part.
Furthermore, those of ordinary skill in the art will appreciate
that the foregoing description is by way of example only, and is
not intended to limit the invention so further described in such
appended claims.
* * * * *