Abstract: There is provided an apparatus (30) and method for conditioning the flow of a mixed phase flow from a supply pipe (101) from a hydrocarbon well. The apparatus (30) comprises an elongate reservoir (11) having a first end for receiving a multi-phase fluid flow from the supply pipe and a second closed end, there being provided a gas outlet (02) from the upper part of the first end, a liquid separation region downstream of the first end, and a liquid outlet (12) from the lower part of the liquid separation region; and a gas-liquid mixer to which the gas and liquid outlets are connected such that the separated gas and liquid may be recombined. The reservoir (11) may accommodate surges of liquid such that the flow rate from the liquid outlet is relatively invariant over time compared to that of the flow received by the apparatus.

Abstract: A system and method for processing natural gas produced from a subsea well is disclosed. The system includes a subsea processing system configured, in use, to receive a natural gas produced from a subsea well, separate free and condensable liquids comprising water and, optionally, liquid hydrocarbons therefrom, and produce a dry single phase gas. The system also includes a surface production facility having a processing system located thereon for processing the free and condensable liquids separated in the subsea processing system and one or more risers for transporting the separated free and condensable liquids to the processing system on the surface production facility. The dry single phase gas produced in the subsea processing system is transported to an onshore production facility via a subsea pipeline. The subsea processing system operates at high pressure and the processing system on the surface production facility operates at low pressure.

Abstract: The present invention relates to an ionic liquid compound that inhibits a formation of a gas hydrate. The compound of the present invention changes an equilibrium temperature and pressure of a gas hydrate in small quantity into a lower temperature and/or a higher pressure, and simultaneously retards the formation of the gas hydrate under the same environment. Thus, the compound of the present invention is used in oil and natural gas industries to effectively inhibit or delay the formation of the gas hydrate under the condition having a low temperature and a high pressure.

Abstract: The invention relates to polymers that can be obtained by polymerizing the monomers (A), (B), and (D), and optionally (C), where (A) is a monomer of formula (I), wherein A stands for C2 to C4 alkylene, B stands for a C2 to C4 alkylene different from A, R stands for hydrogen or methyl, m stands for a number from 1 to 500, n stands for a number from 1 to 500, (B) is an ethylenically unsaturated monomer that contains at least one carboxylic acid function, (C) is optionally a further ethylenically unsaturated monomer different from (A) and (B), (D) is a monomer of formula (II), wherein D stands for C2 to C4 alkylene, E stands for a C2 to C4 alkylene group different from D, F stands for a C2 to C4 alkylene group different from E, R stands for hydrogen or methyl, o stands for a number from 1 to 500, p stands for a number from 1 to 500, q stands for a number from 1 to 500, and wherein the weight fraction of the monomers is 35 to 99% for the macromonomer (A), 0.

Abstract: The invention relates to the use of polymers, containing between 1 and 100 mol % of structural units of the formula (1), wherein R1 means hydrogen or C1-C6 alkyl, A means C2-C4 alkylene groups, and B means C2-C4 alkylene groups, with the stipulation that A is different from B, and x and y mean an integer from 1 to 100 independent of each other, in amounts of 0.01 to 2 wt % relative to the water phase, as gas hydrate inhibitors.

Abstract: The invention provides for the use of copolymers comprising 1 to 99 mol % of structural units of the formula (1) in which R1 is hydrogen or C1-C6-alkyl, A is C2-C4-alkylene groups and B is C2-C4-alkylene groups, with the proviso that A is different than B, and x, y are each independently an integer of 1-100, and 1 to 99 mol % of structural units of the formula (3) in which R6 is hydrogen or C1-C6-alkyl, D is C2-C4-alkylene groups and z is an integer of 1-50, in amounts of 0.01 to 2% by weight, based on the water phase, as gas hydrate inhibitors.

Abstract: A method of inhibiting hydrates in a fluid comprising water and gas comprising adding to the fluid an effective hydrate-inhibiting amount of a composition comprising one or more copolymers of N-alkyl(alkyl)acrylamide monomers and one or more cationic monomers selected from acid and alkyl chloride quaternary salts of N,N-dialkylaminoalkyl(meth)acrylates and N,N-dialkylaminoalkyl(meth)acrylamides.

Abstract: The present invention relates to an absorbent composition composed of an iron oxide and/or hydroxide, activated carbon, promoters and binders, in the form of extruded tablets or granules, capable of absorbing impurities from fluid streams in order to eliminate the impurities, mainly sulfur compounds, contained in these streams. The present invention also relates to the methods for obtaining the absorbents, and to the use thereof for eliminating impurities contained in liquid and gaseous streams.

Abstract: A method for reducing one or more additives in a gaseous hydrocarbon stream (40) such as natural gas, comprising the steps of: (a) admixing an initial hydrocarbon feed stream (10) with one or more additives (20) to provide a multiphase hydrocarbon stream (30); (b) passing the multiphase hydrocarbon stream (30) from a first location (A) to a second location (B2); (c) at the second location (B2), passing the multiphase hydrocarbon stream (30) through a separator (22) to provide one or more liquid streams (50) comprising the majority of the one or more additives, and a gaseous hydrocarbon stream (40) comprising the remainder of the one or more additives; and (d) washing the gaseous hydrocarbon stream (40) in a decontamination unit (24) with a washing stream (60), wherein the washing stream (60) comprises distilled water, to provide an additive-enriched stream (70) and an additive-reduced hydrocarbon stream (80).

Abstract: A method for reducing one or more additives in a gaseous hydrocarbon stream (40) such as natural gas, comprising the steps of: (a) admixing an initial hydrocarbon feed stream (10) with one or more additives (20) to provide a multiphase hydrocarbon stream (30); (b) passing the multiphase hydrocarbon stream (30) from a first location (A) to a second location (B2); (c) at the second location (B2), passing the multiphase hydrocarbon stream (30) through a separator (22) to provide one or more liquid streams (50) comprising the majority of the one or more additives, and a gaseous hydrocarbon stream (40) comprising the remainder of the one or more additives; and (d) washing the gaseous hydrocarbon stream (40) in a decontamination unit (24) with a washing stream (60), wherein the washing stream (60) comprises distilled water, to provide an additive-enriched stream (70) and an additive-reduced hydrocarbon stream (80).

Abstract: Pellet damaging is prevented at the time of pellet charging into a storage tank. There is provided a method of storing a gas hydrate in which pellets obtained by compression molding of powdery gas hydrate are conveyed into a storage tank by the use of a slurry liquor, which method includes pouring a liquid for impact absorption in advance into the storage tank so that the impact on the pellets charged in the storage tank is absorbed by the liquid for impact absorption.

Abstract: A method of protecting a hydrocarbon conduit during a period of reduced hydrocarbon flow is disclosed, where nitrogen is introduced into the conduit at a pressure of 1 to 350 bar g and at a rate of (1.5 to 35)A kg/sec (where A is the internal cross sectional area of the conduit in square meters) for a period of t hours where t=(p×d)/n where d is the length in km of the conduit from the nitrogen introduction location and n is 10 to 400.

Abstract: A drain liquid relief system for a subsea compressor is provided. The system includes a suction scrubber a drain storage tank for collecting drain liquid contaminating the compressor flow in the drain storage tank. The system further includes an intermittently pressurizing device and a suction line connected to the bottom of the drain storage tank. The suction scrubber is connected to the compressor suction nozzle and/or a compressor casing drain line, the suction scrubber being further connected, via a first check valve, to the drain storage tank for collecting the drain liquid in the drain storage tank. The intermittently pressurizing device is adapted to intermittently pressurize the drain storage tank to intermittently blow the drain liquid out of the drain storage tank through the suction line.

Abstract: The present invention relates to a method for removing at least one contaminant from a gaseous stream substantially comprising carbon dioxide. More specifically said method comprising the step of subjecting the gaseous stream to an absorption step in which the absorbent is liquid carbon dioxide.

Abstract: A method for treating a fluid having hydrate-forming constituents is provided. In one or more embodiments, the method includes including a mixture (110) comprising glycol and one or more kinetic inhibitors to a fluid (105) that includes one or more hydrate-forming constituents and water to provide a treated fluid comprising the glycol, one or more kinetic inhibitors, one or more hydrate-forming constituents and water. The treated fluid (125) is then separated at conditions sufficient to provide an oil phase stream and an aqueous phase stream, wherein the aqueous phase stream includes one or more kinetic inhibitors, glycol and water.

Abstract: A process for removing water from a natural gas in an underwater environment is described. The process comprises dehydrating a natural gas feed stream in an apparatus arranged to exchange heat with the underwater environment, preferably including the step of forming hydrates in a hydrate forming zone of a hydrate vessel. The step of forming hydrates in the hydrate zone may comprise the step of introducing the natural gas feed stream into the hydrate vessel through an expansion device with the expansion device is located at and defines a gas inlet to the hydrate vessel. Heat exchange with the hydrate vessel itself need not occur as in one embodiment, heat exchange with the underwater environment takes place through an arrangement of pipes upstream of the hydrate vessel.

Abstract: A subsea compression system and method wherein a wellstream fluid is flowed through a flow line (12) from a reservoir (10) and into a separation vessel (16) for subsequent compression in a compressor (18; 18?, 18?) prior to export of gas. A recycle line (24; 24?, 24?) is fluidly connected at a first end to the compressed wellstream at the outlet side of the compressor (18; 18?, 18?) and at a second end to the wellstream at a location between the separation vessel (16) and the inlet side of the compressor (18; 18?, 18?), the recycle line being capable of controllably (32) feeding fluid due to surge back to the compressor inlet side and avoiding the need to feed the fluid into the separation vessel, because the re-circulated gas is dry both due to having been separated at seawater temperature, and then being heated during recirculation.

Abstract: The invention relates to the use of compounds of formula (1) as corrosion and gas hydrate inhibitors. In said formula: R1 and R2 independently of one another represent C1 to C22 alkyl, C2 to C22 alkenyl, C6 to C30 aryl or C7 to C30 alkyl aryl; R3 represents M, hydrogen or an organic group with between 1 and 100 carbon atoms that optionally contains heteroatoms; A represents a C2 to C4 alkene group; B represents an optionally substituted C1 to C10 alkene group; D represents an ethylene group that is substituted with an organic group comprising between 1 and 600 carbon atoms; X and Y independently of one another represent O or NR4; R4 represents hydrogen, C1 to C22 alkyl, C2 to C22 alkenyl, C6 to C30 aryl or C7 to C30 alkyl aryl; M represents a cation; and n represents a number between 0 and 30.

Abstract: The invention provides the use of compounds of the formula (1) where R1, R2 are each independently C1- to C22-alkyl, C2- to C22-alkenyl, C6- to C30-aryl or C7- to C30-alkylaryl, R3 is C1- to C22-alkyl, C2- to C22-alkenyl, C6- to C30-aryl or C7- to C30-alkylaryl, —CHR5—COO? or —O?, R4 is M, hydrogen or an organic radical which optionally contains heteroatoms and has from 1 to 100 carbon atoms, A is a C2- to C4-alkylene group, B is a C1- to C10-alkylene group, D is an organic radical which optionally contains heteroatoms and has from 1 to 600 carbon atoms, X, Y are each independently O or NR6, R5, R6 are each independently hydrogen, C1- to C22-alkyl, C2- to C22-alkenyl, C6- to C30-aryl or C7- to C30-alkylaryl, and M is a cation n is a number from 1 to 30 as corrosion inhibitors and gas hydrate inhibitors, and also the compounds of formula 1.

Abstract: The invention provides the use of compounds of the formula (1) where R1, R2 are each independently C1- to C22-alkyl, C2- to C22-alkenyl, C6- to C30-aryl or C7- to C30-alkylaryl, R3 is C1- to C22-alkyl, C2- to C22-alkenyl, C6- to C30-aryl or C7- to C30-alkylaryl, —CHR6COO? or —O?, A is a C2- to C4-alkylene group, B is a C1- to C10-alkylene group, X is O or NR7 R6, R7 are each independently hydrogen, C1- to C22-alkyl, C2- to C22-alkenyl, C6- to C30-aryl or C7- to C30-alkylaryl, R4 is a C1- to C50-alkyl, C2- to C50-alkenyl radical, C6- to C50-aryl or C7- to C50-alkylaryl, R5 is hydrogen, —OH or a C1- to C4-alkyl radical, n, m are each independently a number from 0 to 30, x is a number from 1 to 6, as corrosion and gas hydrate inhibitors, and also the compounds of formula 1.

Abstract: A vapor storage canister used to treat fuel vapor of an automotive internal combustion engine. The vapor storage canister includes a casing. A granular formed heat accumulative material is disposed in the casing and includes a powdered heat accumulative agent formed of micro-capsules each of which contains a phase changing material which makes adsorption and release of latent heat in accordance with a temperature change. The granular formed heat accumulative material further includes a binder for binding the heat accumulative agents. Additionally, a granular gas adsorbing material disposed in the casing and mixed with the heat accumulative material.

Abstract: The invention relates to the use of polymers which contain between 1 and 99 mol-% structural units of formula 1, wherein R1 represents hydrogen or C1-C6 alkyl, R2 represents C1-C24-alkyl, C2-C24-alkylene or a C6-C18-aryl radical, which can be substituted with a C1-C12-alkyl group, A represents identical or different C2-C4 alkylene radicals and, x, represents whole number from 2-40 in quantities from 0.01-2 wt-%, in quantities from 0.01 to 2 wt-%, in relation to the aqueous phase. The polymers can be used as gas hydrate inhibitors.

Abstract: A method and a quaternary ammonium or phosphonium composition used therein for inhibiting retarding, mitigating, reducing, controlling and/or delaying formation of hydrocarbon hydrates or agglomerates of hydrates. The method may be applied to prevent or reduce or mitigate plugging of conduits, pipes, transfer lines, valves, and other places or equipment where hydrocarbon hydrate solids may form under the conditions. At least one quaternary ammonium or phosphonium compound is added into the process stream, where the compound may be mixed with another compound selected from other amino alcohols, esters, quaternary ammonium, phosphonium or sulphonium salts, betaines, amine oxides, amides, simple amine salts, and combinations thereof.

Abstract: A method for inhibiting formation of hydrocarbon hydrates in mixtures of water and a hydrate-forming guest molecule involves adding a reaction product to the mixtures in an effective amount to inhibit formation of the hydrocarbon hydrates under conditions otherwise effective to form the hydrocarbon hydrates in the absence of the reaction product. The product is made by the reaction of first reactant that is an amine or polyamine, or alcohol or polyalcohol, with a second, aldehyde reactant and a third reactant that is an alcohol or polyalcohol or, an amide or polyamide. Preferably, if the first and third reactants are both an alcohol or both a polyalcohol, they are not the same. A non-limiting example of a suitable amine would be a fatty alkyl amine, while formaldehyde would be a non-limiting of a suitable aldehyde and polyacrylamide would be a suitable third reactant.

Abstract: A method for inhibiting the formation of gas hydrates within a fluid comprising a gaseous hydrocarbon phase, a liquid hydrocarbon phase and an aqueous phase which method comprises mixing a polymeric emulsifier and optionally a non-ionic non-polymeric co-emulsifier with the fluid prior to subjecting the fluid to conditions under which gas hydrates can be formed so as to generate a water-in-oil emulsion comprising a discontinuous aqueous phase, a continuous liquid hydrocarbon phase and a substantially gas impermeable interfacial layer comprising said polymeric emulsifier and optionally said non-ionic non-polymeric co-emulsifier wherein the aqueous phase is distributed in the continuous liquid hydrocarbon phase in the form of droplets and the substantially gas impermeable interfacial layer encapsulates said droplets.

Abstract: A method for inhibiting hydrate formation in a hydrocarbon flow by adding an amount of a dendrimeric compound effective to inhibit formation of hydrates at conduit temperatures and pressures, and flowing the mixture containing the dendrimeric compound and any hydrates through the conduit. Preferably, a hyperbranched polyester amide is used as hydrate formation inhibitor compound.

Abstract: A separation process, the steps that include: providing an expansion zone, flowing a gaseous fluid into and through the expansion zone, flowing a spray of liquid droplets into the expansion zone to mix with the gaseous fluid and produce nucleation sites, then expanding the flow of mixed gaseous fluid and liquid droplets to cause condensation of gas onto the liquid droplets, and then centrifuging liquid droplets into a separation layer.

Abstract: Graft polymers are used as gas hydrate inhibitors.

Abstract: A method for inhibiting the formation of gas hydrates within a fluid comprising a gaseous hydrocarbon phase, a liquid hydrocarbon phase and an aqueous phase which method comprises mixing a polymeric emulsifier and optionally a non-ionic non-polymeric co-emulsifier with the fluid prior to subjecting the fluid to conditions under which gas hydrates can be formed so as to generate a water-in-oil emulsion comprising a discontinuous aqueous phase, a continuous liquid hydrocarbon phase and a substantially gas impermeable interfacial layer comprising said polymeric emulsifier and optionally said non-ionic non-polymeric co-emulsifier wherein the aqueous phase is distributed in the continuous liquid hydrocarbon phase in the form of droplets and the substantially gas impermeable interfacial layer encapsulates said droplets.

Abstract: Methods are provided for the selective removal of CO2 from a multicomponent gaseous stream to provide a CO2 depleted gaseous stream. In practicing the subject methods, an initial multicomponent gaseous stream that includes a gaseous CO2 hydrate promoter is contacted with an aqueous fluid, e.g., CO2 nucleated water, in a hydrate formation reactor under conditions of selective CO2 clathrate formation to produce a CO2 clathrate slurry and CO2 depleted gaseous stream. Also provided are systems that find use in practicing the subject methods. The subject methods and systems find use in a variety of applications where it is desired to selectively remove CO2 from a multicomponent gaseous stream.

Abstract: A method for recovering large volumes of hydrocarbon fuels, particularly methane (CH4), using commercially available reagents which are strongly water-soluble and soluble in liquid CO2 in the presence of liquid CO2 injected into the methane hydrate formation. The reagents which are strongly water-soluble and soluble in liquid CO2 form dilute aqueous acids that significantly increase the rate of conversion of methane hydrate into methane and CO2 hydrate, thereby allowing the natural gas to be released in a form that can then be recovered in large quantities using conventional devices. The preferred embodiment uses SO3, HCl or other strongly water soluble gas to cause the methane hydrate ice crystals to melt and form an aqueous solution. The aqueous solution contacts the methane hydrate ice on one side and liquid carbon dioxide on the other side.

Abstract: A method for the separation of non-hydrocarbon gases from hydrocarbon gases, the method comprising the steps of: adding water and an agent adapted to reduce the interfacial tension between water and hydrocarbons to a first stream of desired hydrocarbon and undesired non-hydrocarbon gases to form a gas-agent-water mixture; pressurising the gas-agent-water mixture; and cooling the gas-water-agent mixture to initiate the formation of a hydrate richer in desired hydrocarbons and leaner in undesired non-hydrocarbons relative to the first stream of desired hydrocarbon and undesired non-hydrocarbon gases.

Abstract: A method for recovering large volumes of hydrocarbon fuels, particularly methane (CH4), using commercially available reagents which are strongly water-soluble and soluble in liquid CO2 in the presence of liquid CO2 injected into the methane hydrate formation. The reagents which are strongly water-soluble and soluble in liquid CO2 form dilute aqueous acids that significantly increase the rate of conversion of methane hydrate into methane and CO2 hydrate, thereby allowing the natural gas to be released in a form that can then be recovered in large quantities using conventional means. The preferred embodiment uses SO3, HCl or other strongly water soluble gas to cause the methane hydrate ice crystals to melt and form an aqueous solution. The aqueous solution contacts the methane hydrate ice on one side and liquid carbon dioxide on the other side.

Abstract: The invention relates to the use of polymers which contain between 1 and 99 mol-% structural units of formula 1, 1

Abstract: Methods of treatment of fluids produced by an oil or gas well following a stimulation operation, allowing separation from the fluids and re-injection of oil and gas hydrocarbons in a production pipeline under pressure, and allowing achievement of suitable quality for the residual fluids compatible with their rejection, for example into the sea, including the following three elements; neutralization of the fluids by mixing with a high pH chemical, until the resulting pH reaches a level compatible with the equipment and pipes; use of optimized emulsion breakers in a phase separator, selected for best results with the fluids produced by the well, to accelerate the separation of oil from the fluids, and to lower the residual oil content in the fluids to levels compatible with environmental regulations; and use of a multi-phase pump to pump the oil and gas hydrocarbons produced and reinject them in a pipeline under pressure.

Abstract: The present invention relates to a method for separation of gas constituents from a multicomponent gaseous mixture employing a hydrate promoter. The method for separation of gas constituents from a multicomponent gaseous mixture includes the steps of reacting an aqueous solution containing a hydrate promoter with a multicomponent gaseous mixture to form a gas hydrate condensed with the gas constituents of high gas hydrate forming power and dissociating a specific gas component from the gas hydrate. In accordance with the present invention, a specific gas component can be seperated from a multicomponent gaseous mixture under a pressure much lower than that of the prior art method, which makes possible its practical application in various industrial areas emitting exhaust gases.

Abstract: A method and a composition used therein are disclosed for inhibiting formation of hydrocarbon hydrates. The composition comprises an onium compound, an amine salt and, optionally, a solvent.

Abstract: In order to improve the transport of oilfield effluents comprising water, a gas and possibly a liquid hydrocarbon phase under thermodynamic conditions which can lead to the formation of hydrates, a formulation containing at least two additives, one of which behaves as a hydrate crystal nucleation agent, is added to the effluent to be transported.

Abstract: A method for preventing scale formation in a wet type exhaust gas treating apparatus is disclosed. An exhaust gas is contacted with a washing liquid containing water. The washing liquid contains at least one chelating agent which reacts with ions becoming a cause of scale formation to form a water-soluble chelate compound.

Abstract: Disclosed herein are clathrate hydrate inhibitors and the method of inhibiting the formation, agglomeration, and deposition of clathrate hydrate using the inhibitors. The clathrate hydrate inhibitor comprises a macromolecular compound in which 3-15 membered ring pendant is connected to the polymer main chain via a specific spacer group such as homo- or co-polymer of (meth)acryloyl pyrrolidine, pyrrolidinocarbonylethyl (meth)acrylate, 2-oxo-pyrrolidino-ethyl (meth)acrylate, glyoxyloyl pyrrolidine, pyrrolidinocarbonyl aspartate.

Abstract: A method is disclosed for inhibiting the plugging of a conduit for the transport of hydrocarbon fluids by gas hydrates.

Abstract: A method for inhibiting the formation of gas hydrates in a petroleum fluid having hydrate-forming constituents is claimed. More specifically, the method can be used to treat a petroleum fluid, such as natural gas conveyed in a pipe, to inhibit the formation of a hydrate flow restriction in the pipe. The hydrate inhibitors used for practicing the method comprise substantially water soluble homopolymers and copolymers of surfactant monomers, wherein the surfactant monomer unit may be represented by the formula: where R1 and R2 independently are hydrogen or a methyl group, M is a metal cation, n is a number sufficient to produce a number average molecular weight between 1000 and 6,000,000, and o is a number from 1 to 5.

Abstract: A composition is provided herein for preventing or retarding the formation of gas hydrates or for reducing the tendency of gas hydrates to agglomerate, during the transport of a fluid comprising water and a hydrocarbon, through a conduit. The composition is a homopolymer of vinyl caprolactam having the low molecular weight in the range of 500 to 2500, or copolymers or terpolymers thereof, and a polyoxyalkylenediamine or a polyoxyarylenediamine. Such homopolymers, copolymers and terpolymers, preferably are made and applied in the defined solvent, which, most preferably, is a glycol ether such as 2-butoxyethanol.

Abstract: The invention relates to an additive for inhibiting gas hydrate formation, containing a) from 5 to 90% by weight of 2-isobutoxyethanol, b) from 5 to 60% by weight of a copolymer which has structural units which are derived from maleic acid, maleic anhydride or derivatives of maleic acid or of maleic anhydride, and c) at least 10% by weight of water or a monohydric or polyhydric alcohol, except the 2-isobutoxyethanol, or mixtures of the stated substances, based on the total weight of the additive, the sum of the contents of compounds a) and b) being from 10 to 90% by weight, and a process for inhibiting gas hydrate formation using 2-isobutoxyethanol.

Abstract: A method is disclosed for inhibiting the plugging of a conduit for the transport of hydrocarbon fluids by gas hydrates, wherein use is made of a hydrate formation inhibitor component of formula(R.sub.1) (R.sub.2) (R.sub.3) (R.sub.4)A.sup.+ Y.sup.- (I)wherein two of R.sub.1 -R.sub.4 are independently normal or branched alkyls having 4 or 5 carbon atoms, two of R.sub.1 -R.sub.4 are independently representing organic moieties having at least 8 carbon atoms, A represents a nitrogen or a phosphorus atom, Y represents an anion and wherein at least one of R.sub.1 -R.sub.4 represents a --(CH.sub.2 --CHR.sub.5 --O).sub.p --(CH.sub.2).sub.q --(CHR.sub.6 --CH.sub.2).sub.r --(CH.sub.2 --CHR.sub.7).sub.s --(CHR.sub.8).sub.t --O--C(O)--R.sub.9 moiety with the meaning as defined in the description.

Abstract: A method for inhibiting the formation of clathrate hydrates in a fluid having hydrate-forming constituents involves treating the fluid with an inhibitor comprising a substantially water soluble polymer having a polymer backbone .with a pendant C.sub.1 --C.sub.3 alkyl group; the polymer having an average molecular weight between about 1,000 and about 6,000,000. Preferably, the pendant alkyl group is a methyl group. The rate of nucleation, growth, and/or agglomeration of gas hydrate crystals in a petroleum fluid stream Is reduced using the alkylated polymer backbone inhibitor, thereby inhibiting the formation of a hydrate blockage in the pipe conveying the petroleum fluid stream. Test results are disclosed which unexpectedly show that alkylating the polymer backbone with a methyl group will produce a subcooling for the alkylated polymer that is at least about 2.degree. F. (about 1.1.degree. C.) greater than its nonalkylated counterpart.

Abstract: The present application relates to a method for inhibiting gas hydrate formation, which involves the addition to the aqueous phase, in the case of multiphase mixtures comprising water, gas and possibly condensate, of an amine oxide or salts thereof.

Abstract: A process for slowing the growth and/or agglomeration of hydrates in a fluid comprising water and gases by adding at least one essentially water-soluble polyoxyalkylene glycol macromer or at least one essentially water-soluble polymer containing a single macromer or a plurality of different macromer units of polyoxyalkylene glycol or a mixture of essentially water-soluble macromers and/or polymacromers. It is also possible to both retard the formation of hydrates and to substantially slow their growth and limit their agglomeration during crystallization by combining polyoxyalkylene glycol macromer type structures with kinetic additive type structures which are known to inhibit hydrate formation.

Abstract: A composition for preventing or retarding the formation of gas hydrates or for reducing the tendency of gas hydrates to agglomerate, during the transport of a fluid comprising water and a hydrocarbon, through a conduit, comprising, (a) a polymer or copolymer selected from a terpolymer of vinyl pyrrolidone, vinyl caprolactam and an ammonium derivative monomer having from 6 to 12 carbon atoms, selected from the group consisting of dialkyl aminoalkyl methacrylamide, dialkyl dialkenyl ammonium halide and a dialkylamino alkyl acrylate or methacrylate, a copolymer of vinyl pyrrolidone and vinyl caprolactam, and a homopolymer of vinyl caprolactam, and (b) an alcohol containing three to five carbon atoms and one hydroxy group.

Abstract: The present invention provides improved methods of drying pipelines containing water which are to transport hydrate forming gaseous fluids. The methods basically comprise flowing a liquid which forms an azeotrope mixture with water into contact with water in a pipeline, the amount of the azeotropic liquid being sufficient to form an azeotrope mixture with the water whereby as the mixture is evaporated in the pipeline, the water concentration in the remaining mixture does not reach that concentration which will form hydrates with the hydrate forming gaseous fluid.