Embodiments of the present disclosure are directed to a method of making a reaction inhibiting polymer having a formula of M—CO—NR. The method may comprise reacting PAA with an organic coupling reagent and at least one alicyclic amine to produce the reaction inhibiting polymer. In accordance with another embodiment of the present disclosure, a method of making an acryloyl monomer having a formula of R.sub.a—CO—NR may comprise reacting an acrylic acid with an organic coupling reagent and an alicyclic amine to form the acryloyl monomer. R.sub.a may be an alkylene moiety, M may be a poly(acrylic) acid backbone. NR may be an alicyclic amine moiety coupled to the polymer backbone or coupled to the alkylene moiety.

A method of dissolving a gas hydrate in a pipeline includes introducing a gas hydrate dissolving solution into the pipeline and allowing the gas hydrate dissolving solution to at least partially dissolve the gas hydrate in the pipeline. The gas hydrate dissolving solution includes a strong acid and a weak organic acid, and the strong acid expedites the reaction.

A system for recovering natural gas liquid from a gas source, comprising compression means (206) for increasing the temperature and pressure of the fluid from the gas source, cooling means (230) for cooling the fluid from the compression means, a gas/gas heat exchanger (204), fluid from the gas source flowing from a first inlet to a first outlet; at least one separator (208) for receiving the fluid from the first outlet of the gas/gas heat exchanger (204) and separating liquid from the gas, the gas from the separator being directed to expansion means (206) for reducing the temperature and pressure of the gas, the aqueous part of the liquid from the separator and/or the gas from the expansion means being directed to the gas/gas heat exchanger (204) where it flows therethrough from a second inlet to a second outlet for cooling the fluid flowing between the first inlet and first outlet, wherein injection means are provided between the cooling means and the gas/gas heat exchanger for saturating the gas with a liquid agent, wherein the liquid agent comprises an evaporant and an antifreeze agent; and a recovery vessel (240) is provided downstream of the second outlet, the antifreeze agent being recovered therein for injection into the fluid from the gas source upstream of the first inlet.

A method of dissolving a gas hydrate in a pipeline includes introducing a gas hydrate dissolving solution into the pipeline and allowing the gas hydrate dissolving solution to at least partially dissolve the gas hydrate in the pipeline. The gas hydrate dissolving solution includes a glycol, dimethylformamide, or both, and has a boiling point of greater than 80° C. A method of dissolving a gas hydrate in a pipeline may also include introducing a gas hydrate dissolving solution into the pipeline and allowing the gas hydrate dissolving solution to at least partially dissolve the gas hydrate in the pipeline. The gas hydrate dissolving solution includes comprises a glycol, dimethylformamide, cesium formate, potassium formate, or combinations thereof, and has a flash point of greater than 50° C.

A method of dissolving a gas hydrate in a pipeline includes introducing a gas hydrate dissolving solution into the pipeline and allowing the gas hydrate dissolving solution to at least partially dissolve the gas hydrate in the pipeline. The gas hydrate dissolving solution includes cesium formate, potassium formate, or both, and has a flash point of greater than 50° C.

The present invention provides a drain apparatus (200) for use in a subsea pipeline to remove liquid from a multiphase flow in the subsea pipeline. The drain apparatus comprises a first channel (20) for carrying a multiphase flow comprising liquid and gas phases; and liquid extraction means (11, 12, 14, 18) for extracting the liquid phase from the multiphase flow in the first channel (20). The internal diameter of the first channel (20) is substantially the same as an internal diameter of a subsea pipe arranged to carry the multiphase flow in the subsea pipeline, such that a pig travelling along the subsea pipe can pass through the first channel (20). The present invention also provides a subsea pipeline comprising a subsea pipe for transporting a multiphase flow subsea; and at least one drain. The at least one drain is disposed partway along a gradient in the subsea pipe to reduce liquid holdup.

A low dosage hydrate inhibitor blend comprising a cationic surfactant and a co-surfactant. The cationic surfactant has the structural formula: ##STR00001##
wherein: R1 is an alkyl group or alkenyl group having from 5 to 22 carbon atoms, R2 and R3 are alkyl groups having from 1 to 6 carbon atoms, R4 is a hydrogen atom or an alkyl group having from 1 to 6 carbon atoms, and X— is selected from the group of a carboxylate, an acrylate, a methacrylate, a halide, a phosphonate, a sulfate, a sulfonate, a hydroxide, a carbonate, or any combination thereof; and The co-surfactant is present in the inhibitor blend in an amount of no greater than about 10 percent by weight based on the total weight of the blend.

This disclosure relates to anti-agglomerant low dosage hydrate inhibitors that can inhibit the formation of hydrate agglomerants and/or plugs. Thus, provided herein are carboxy alkyl ester compounds that can be used in hydrate inhibitor compositions and methods of inhibiting formation of hydrate agglomerants in a fluid comprising water, a gas, and optionally a liquid hydrocarbon. Also provided herein are methods of making the carboxy alkyl ester compound.

The instant invention concerns a gas hydrate inhibitor comprising an N alkyl N′ (N″,N″-dialkylammoniumalkyl)dicarboxylic acid diamide salt represented by the formula (I) ##STR00001##
wherein R is an alkyl or alkenyl group having from 8 to 22 carbon atoms, R.sup.1 is hydrogen, a C.sub.1- to C.sub.22 alkyl group or a C.sub.3- to C.sub.22 alkenyl group, R.sup.2 and R.sup.3 are each independently an alkyl group containing 1 to 10 carbon atoms or together form an optionally substituted ring having 5 to 10 ring atoms, wherein the ring may carry up to 3 substituents, R4 is hydrogen, A is an optionally substituted hydrocarbyl group containing from 1 to 18 carbon atoms, B is an alkylene group having from 2 to 6 carbon atoms, Y is NR.sup.5, R.sup.5 is hydrogen, a C.sub.1- to C.sub.22 alkyl group or a C.sub.3- to C.sub.22 alkenyl group, and M− is an anion,
a process for producing a compound according to formula (I), the use of an N alkyl N′—(N″,N″-dialkylammoniumalkyl)dicarboxylic acid diamide salt of the formula (I) as an anti-agglomerant for gas hydrates, and a method for inhibiting the agglomeration of gas hydrates which comprises the addition of an N alkyl N′ (N″,N″dialkylammmoniumalkyl)dicarboxylic acid diamide salt of the formula (I) to a fluid containing gas and water.

This invention relates to a method for inhibiting the agglomeration of gas hydrates, comprising the injection of an anti-agglomerant comprising a N,N-dialkyl-ammoniumalkyl fatty acid amide represented by the formula (I) ##STR00001##
wherein R.sup.1 is an alkyl or alkenyl group having from 7 to 21 carbon atoms, R.sup.2 and R.sup.3 are each independently an alkyl group containing 1 to 10 carbon atoms, or together form an optionally substituted ring having 5 to 10 ring atoms, wherein the ring may carry up to 3 substituents, R.sup.4 is hydrogen or an alkyl group having 1 to 6 carbon atoms, R.sup.5 is hydrogen or an optionally substituted hydrocarbyl group having 1 to 22 carbon atoms and A is an alkylene group having two or three carbon atoms,
into a fluid comprising gas, water and oil under conditions prone to the formation of gas hydrates,
wherein the N,N-dialkyl-ammoniumalkyl fatty acid amide represented by formula (I) is produced by the aminolysis of an ester of a fatty acid and a C.sub.1- to C.sub.4-alcohol with an N,N-dialkylamino alkyl amine and subsequent neutralization with a carboxylic acid.