MULTIFUNCTIONAL PRODUCT WITH HYDROGEN SULFIDE SCAVENGING AND HYDRATE INHIBITION CAPACITY
Disclosed herein are scavenging and hydrate inhibiting multifunctional compositions useful in applications relating to the production, transportation, storage, and separation of crude oil and natural gas. Also disclosed herein are methods of using the compositions as scavengers and hydrate inhibitors, particularly in applications relating to the production, transportation, storage, and separation of crude oil and natural gas.
1 . A method of scavenging hydrogen sulfide and preventing the formation of hydrates in a medium comprising:
adding an effective amount of a multifunctional composition to the medium, wherein the multifunctional composition comprises a scavenger, a hydrate inhibitor, and optionally an acid, a base, and/or a solvent, wherein the scavenger comprises a member selected from the group consisting of an acetal group, a hemiacetal group, a dialdehyde, a cyclic compound, and any combination thereof, and the hydrate inhibitor comprises a caprolactam or a pyrrolidone.
2 . The method of claim 1 , wherein the medium comprises gas, oil, water or any combination thereof.
3 . The method of claim 1 , wherein an oil or gas well comprises the medium, and the multifunctional composition is added to the medium through a gas lift or an umbilical tubing.
4 . The method of claim 1 , wherein the multifunctional composition is anhydrous and optionally excludes nitrogen-containing compounds.
5 . The method of claim 1 , wherein the multifunctional composition comprises from about 50% to about 97%, by weight, of the scavenger, and from about 50% to about 3%, by weight, of the hydrate inhibitor.
6 . The method of claim 1 , wherein the scavenger comprises a structure selected from the group consisting of
wherein R 1 is hydrogen (H) or a hydrocarbon group with 1 to 5 carbon atoms, R 2 is H or a hydrocarbon group with 1 to 5 carbon atoms, R 3 is a hydrocarbon group with 1 to 5 carbon atoms, a cetal, or a hemiacetal, and R 4 is H or a hydrocarbon group with 1 to 5 carbon atoms.
7 . The method of claim 1 , wherein the scavenger comprises ethylene glycol formaldehyde, glycerol formal, or any combination thereof.
8 . The method of claim 1 , wherein the hydrate inhibitor comprises a compound selected from the group consisting of N-vinyl-2-caprolactam, a terpolymer of N-vinyl-2-caprolactam, 2-acrylamido-2-methylpropane sulfonic acid, N-vinyl-2-pyrrolidone, poly-N-vinyl-2-caprolactam, cyclic N-vinyl amides, acyclic N-vinyl amides, and any combination thereof.
9 . The method of claim 1 , wherein the hydrate inhibitor comprises a structure selected from the group consisting of
wherein R is independently selected from the group consisting of H, an alkyl group, a cycloalkyl group, and an aryl group;
m is a number from 1-60;
n is a number from 1-60;
M is a member selected from the group consisting of H, Na, K, Li, Ca, Ba, Mg2 + , Al3 + , and NH 4 + ; and
y is 1 or 2.
10 . The method of claim 1 , wherein the multifunctional composition comprises a pH between about 4.5 and about 9.
11 . The method of claim 1 , wherein the dialdehyde comprises the following generic structure:
wherein R 1 comprises hydrogen (H) or a hydrocarbon group with 1 to 5 carbon atoms, R 2 comprises H or a hydrocarbon group with 1 to 5 carbon atoms, and n is a number greater than or equal to 1.
12 . The method of claim 1 , wherein the cyclic compound comprises the following general formula:
wherein R 1 may be selected from a hydrogen (H), a hydrocarbon group with 1 to 5 carbon atoms, or an alcohol group containing 1 or 2 carbon atoms; R 2 may be selected from hydrogen (H), a hydrocarbon group with 1 to 5 carbon atoms, or an alcohol group containing 1 or 2 carbon atoms, and; R 3 may be selected from hydrogen (H), a hydrocarbon group with 1 to 5 carbon atoms, or an alcohol group containing 1 or 2 carbon atoms.
13 . A multifunctional composition, comprising:
a hydrate inhibitor comprising a caprolactam or a pyrrolidone,
a scavenger comprising a member selected from the group consisting of an acetal group, a hemiacetal group, a dialdehyde, a cyclic compound, and any combination thereof, and
optionally a member selected from the group consisting of an acid, a base, a solvent, and any combination thereof.
14 . The composition of claim 13 , wherein the scavenger comprises a structure selected from the group consisting of
wherein R 1 is hydrogen (H) or a hydrocarbon group with 1 to 5 carbon atoms, R 2 is H or a hydrocarbon group with 1 to 5 carbon atoms, R 3 is a hydrocarbon group with 1 to 5 carbon atoms, a cetal, or a hemiacetal, and R 4 is H or a hydrocarbon group with 1 to 5 carbon atoms.
15 . The composition of claim 13 , wherein the scavenger comprises ethylene glycol formaldehyde, glycerol formal, or any combination thereof.
16 . The composition of claim 13 , wherein the hydrate inhibitor comprises a compound selected from the group consisting of N-vinyl-2-caprolactam, a terpolymer of N-vinyl-2-caprolactam, 2-acrylamido-2-methylpropane sulfonic acid, N-vinyl-2-pyrrolidone, poly-N-vinyl-2-caprolactam, cyclic N-vinyl amides, acyclic N-vinyl amides, and any combination thereof.
17 . The composition of claim 13 , wherein the hydrate inhibitor comprises a structure selected from the group consisting of
wherein R is independently selected from the group consisting of H, an alkyl group, a cycloalkyl group, and an aryl group;
m is a number from 1-60;
n is a number from 1-60;
M is a member selected from the group consisting of H, Na, K, Li, Ca, Ba, Mg2 + , Al3 + , and NH 4 + ; and
y is 1 or 2.
18 . The composition of claim 13 , wherein the multifunctional composition comprises about 70%-98%, by weight, of the scavenger, wherein the scavenger comprises 1,2-ethanediylbis(oxy)bismethanol, about 2%-8%, by weight, of the hydrate inhibitor, wherein the hydrate inhibitor comprises 1-ethenylazepan-2-one-1-ethenylpyrrolidin-2-one, about 5%-10%, by weight, of the solvent, wherein the solvent comprises ethanol, and about 0%-1%, by weight, of the acid, wherein the acid comprises acetic acid.
19 . The composition of claim 13 , wherein the dialdehyde comprises the following generic structure:
wherein R 1 comprises hydrogen (H) or a hydrocarbon group with 1 to 5 carbon atoms, R 2 comprises H or a hydrocarbon group with 1 to 5 carbon atoms, and n is a number greater than or equal to 1.
20 . The composition of claim 13 , wherein the cyclic compound comprises the following general formula:
wherein R 1 may be selected from a hydrogen (H), a hydrocarbon group with 1 to 5 carbon atoms, or an alcohol group containing 1 or 2 carbon atoms; R 2 may be selected from hydrogen (H), a hydrocarbon group with 1 to 5 carbon atoms, or an alcohol group containing 1 or 2 carbon atoms, and; R 3 may be selected from hydrogen (H), a hydrocarbon group with 1 to 5 carbon atoms, or an alcohol group containing 1 or 2 carbon atoms.