Low dose gas hydrate inhibitor compositions
View Patent ↗The present invention generally relates to one or more compositions and methods for inhibiting the formation of gas hydrate agglomerates in a fluid. The fluid may be contained, for example, in an oil or gas pipeline or refinery.
1. A method for inhibiting gas hydrate formation in a fluid comprising a hydrocarbon and water, the method comprising adding to the fluid an effective amount of an inhibitor composition to inhibit gas hydrate formation in the fluid, the inhibitor composition comprising an polyamine derived from reaction of a first amine being a diamine, a triamine, or a polyamine, and a second amine of a tertiary amine of formula 1 or a quaternary amine of formula 2 having the structures of
wherein
R 1 , R 2 , and R 3 are each independently —R 5 —Z;
R 4 is alkyl;
R 5 is C 1 to C 20 alkylene, substituted C 1 to C 20 alkylene, arylene, aralkylene, or C 1 to C 20 alkylene wherein one or more of the —CH 2 — groups of the alkylene group is replaced with an amide, a carbonyl, an ether, an ester, a cycloalkyl, or a heterocyclo functional group;
R 6 is independently hydrogen or alkyl; and
Z is —NHR 6 , —OH, —C(O)OR 6 , or —C(O)NHR 6 .
2. The method of claim 1 wherein the inhibitor composition further comprises a gas hydrate inhibitor agent.
3. The method of claim 2 wherein the gas hydrate inhibitor agent is a polyvinylcaprolactone; a polyvinylpyrrolidone; a copolymer of a vinylcaprolactone and a vinylpyrrolidone; poly(N-alkyl(alkyl)acrylamide), a copolymer of N-alkyl(alkyl)acrylamide and alkyl chloride quaternary salts of N,N-dialkylaminoalkyl(meth)acrylates, a copolymer of N-alkyl(alkyl)acrylamide and alkyl chloride quaternary salts of N,N-dialkylaminoalkyl(meth)acrylamides, a terpolymer of a vinylcaprolactone, a vinylpyrrolidone, and a vinyl acetate; a dendrimeric polyesteramide derived from hexahydrophthalic anhydride; diisopropanol amine, and N,N-bis(3-dimethylaminopropyl)amine; a substituted polyethyleneimines; a polyoxyalkylenediamine; a dicarboxylic acid-polyol polyester; a polycyclicpolyether polyol; a hyperbranched polyester polyol having hydroxyl end groups; a hyperbranched polyester polyamine; a hyperbranched polyamidoamine; a linear polyester polyamine; or a combination thereof.
4. The method of claim 3 wherein the gas hydrate inhibitor agent comprises a copolymer of a polyvinylcaprolactone and a polyvinylpyrrolidone; a terpolymer of a polyvinylcaprolactone, a polyvinylpyrrolidone, and a polyvinyl acetate; or a combination thereof.
5. The method of claim 1 wherein the first amine is ethylene diamine, propylene diamine, butylene diamine, pentylene diamine, hexylene diamine, heptylene diamine, octylene diamine, nonylene diamine, decylene diamine, diethylene triamine, dipropylene triamine, dibutylene triamine, dipentylene triamine, dihexylene triamine, triethylene tetraamine, tripropylene tetraamine, tributylene tetraamine, tripentylene tetraamine, trihexylene tetraamine, tetraethylene pentaamine, tetrapropylene pentaamine, pentaethylene hexamine, pentapropylene hexamine, N 1 ,N 2 -dimethylethane-1,2-diamine, N 1 ,N 3 -dimethylpropane-1,3-diamine, N 1 ,N 4 -dimethylbutane-1,4-diamine, N 1 ,N 5 -dimethylpentane-1,5-diamine, N 1 ,N 6 -dimethylhexane-1,6-diamine, p-diaminoethylbenzene, 1,4-diaminocyclohexane, or a combination thereof.
6. The method of claim 5 wherein the first amine is ethylene diamine, 1,6-hexylene diamine, or a combination thereof.
7. The method of claim 1 wherein the inhibitor composition comprises a tertiary amine of formula 1.
8. A method for inhibiting gas hydrate formation in a fluid comprising a hydrocarbon and water, the method comprising adding to the fluid an effective amount of an inhibitor composition to inhibit gas hydrate formation in the fluid, the inhibitor composition comprising an polyamine derived from reaction of a first amine being a diamine, a triamine, or a polyamine, and a second amine that is a quaternary amine of Formula 2
wherein
R 1 , R 2 , and R 3 , are each independently —R 5 —Z or two or more of R 1 , R 2 , and R 3 together with the nitrogen atom form a heterocyclo group;
R 4 is alkyl;
R 5 is C 1 to C 20 alkylene, substituted C 1 to C 20 alkylene, arylene, aralkylene, or C 1 to C 20 alkylene wherein one or more of the —CH 2 — groups of the alkylene group is replaced with an amide, a carbonyl, an ether, an ester, a cycloalkyl, or a heterocyclo functional group;
R 6 is independently hydrogen or alkyl; and
Z is —NHR 6 , —OH, —C(O)OR 6 , or —C(O)NHR 6 .
9. The method of claim 8 wherein R 4 is methyl, ethyl, propyl, or butyl.
10. The method of claim 1 wherein R 5 is C 1 to C 10 alkylene.
11. The method of claim 10 wherein R 5 is C 1 to C 6 alkylene.
12. The method of claim 10 wherein R 5 is ethylene.
13. The method of claim 12 wherein Z is —OH or —C(O)OR 6 .
14. The method of claim 1 wherein R 5 is ethylene and Z is —OH.
15. The method of claim 1 wherein R 5 is ethylene, Z is —C(O)OR 6 , and R 6 is methyl or ethyl.
16. The method of claim 8 wherein R 5 is C 1 to C 6 alkylene.
17. The method of claim 8 wherein R 2 and R 3 are —R 5 —Z, R 5 is ethylene, Z is —C(O)OR 6 , and R 6 is methyl or ethyl.
18. The method of claim 8 wherein the first amine is ethylene diamine, propylene diamine, butylene diamine, pentylene diamine, hexylene diamine, heptylene diamine, octylene diamine, nonylene diamine, decylene diamine, diethylene triamine, dipropylene triamine, dibutylene triamine, dipentylene triamine, dihexylene triamine, triethylene tetraamine, tripropylene tetraamine, tributylene tetraamine, tripentylene tetraamine, trihexylene tetraamine, tetraethylene pentaamine, tetrapropylene pentaamine, pentaethylene hexamine, pentapropylene hexamine, N 1 ,N 2 -dimethylethane-1,2-diamine, N 1 ,N 3 -dimethylpropane-1,3-diamine, N 1 ,N 4 -dimethylbutane-1,4-diamine, N 1 ,N 5 -dimethylpentane-1,5-diamine, N 1 ,N 6 -dimethylhexane-1,6-diamine, p-diaminoethylbenzene, 1,4-diaminocyclohexane, or a combination thereof.
19. The method of claim 17 wherein the first amine is ethylene diamine, 1,6-hexylene diamine, or a combination thereof.