Abstract: An acidizing composition and a method of acidizing a hydrocarbon bearing subterranean formation in the presence of ferric ions are provided. The acidizing composition includes an aqueous mineral acid solution, an electron donor agent and an electron transfer agent, the electron transfer agent being a source of molybdenum ions. When the aqueous mineral acid solution includes hydrochloric acid in an amount greater than approximately 17% by weight, the acidizing composition further includes a supplemental electron transfer agent, the supplemental electron transfer agent being a source of iodide ion or iodine. The electron donor agent and electron transfer agent function together to reduce ferric ion present in the mineral acid solution to ferrous ion which in turn prevents ferric hydroxide and/or free sulfur from precipitating out of the solution and reduces the formation of sludge in crude oil in the formation.

Abstract: A process for preparing a composition comprising a mixture with ester and amine function in the form of ester-amines, amines, salts of amines, monoglycerides and diglycerides all derived from monomeric, dimeric, trimeric, and/or tetrameric fatty acids contained in polymerized polyunsaturated oil comprising: (a) polymerizing a polyunsaturated vegetable or animal oil to form a polymerized oil, (b) treating the polymerized oil with water vapor, and (c) reacting the polymerized oil with an excess of at least one compound containing at least one hydroxyl function and at least one tertiary amine function, optionally in the presence of a catalyst. Said methods further comprise adding the compositions to an oil effluent as dispersing agents for hydrates.

Abstract: An oil field production chemical, especially a scale inhibitor, is in the form of particles thereof carrying a coating e.g. of a dispersing agent. The coating may be polymeric such as an oligomeric polyacid polyester, a polymeric alkoxylated alcohol or a fatty acid polyamine condensate or it may also be a surfactant and may be used in the form of a suspension in an inert oil, such as diesel oil or kerosene which may be injected into a subterranean formation to inhibit the formation of deposits, e.g. scale in oil wells over a longer period than compounds free of the coating.

Abstract: An acidic fluid that is useful in stimulation and workover operations, and in particular, for the control of iron in acidizing operations, the removal of alkaline earth carbonate scale in scale removal operations, and matrix or fracture acidizing operations, comprises an acid, such as hydrochloric acid; water; and a hydroxyethylaminocarboxylic acid. Preferred hydroxyethylaminocarboxylic acids are hydroxyethylethylenediaminetriacetic acid (HEDTA) and hydroxyethyliminodiacetic acid (HEIDA). Also disclosed herein are methods of controlling iron, removing alkaline earth carbonate scale, or matrix or fracture acidizing, involving the use of the acidic fluid.

Abstract: A method of inhibiting or retarding formation of hydrates from water and a lower alkane, such as methane or ethane, involves adding additives which comprise (i) a corrosion inhibitor and (ii) a salt which is of formula [R1(R2)XR3]+Y−, wherein each of R1, R2 and R3 is bonded directly to X, each of R1 and R2, which may be the same or different is an alkyl group of at least 4 carbons, X is S, NR4 or PR4, wherein each of R3 and R4 which may be the same or different represents hydrogen or an organic group, with the proviso that at least one of R3 and R4 is an organic group of at least 4 carbons, and Y is an anion, the additives being added in an amount effective to inhibit or retard hydrate formation, to a medium susceptible to hydrate formation.

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: An oil field production chemical, especially a scale inhibitor, is in the form of particles thereof carrying a coating e.g. of a dispersing agent. The coating may be polymeric such as an oligomeric polyacid polyester, a polymeric alkoxylated alcohol or a fatty acid polyamine condensate or it may also be a surfactant and may be used in the form of a suspension in an inert oil, such as diesel oil or kerosene which may be injected into a subterranean formation to inhibit the formation of deposits, e.g. scale in oil wells over a longer period than compounds free of the coating.

Abstract: An additive for inhibiting the formation of gas hydrates in connection with hydrocarbon production and transportation comprising the water-soluble polymers comprising structural elements of the formula wherein each R is independently H or C1-C5-alkyl; X is H, an alkaline or earth alkaline metal or a quaternary ammonium group; R1 is H or C1-C18-alkyl; and R2 is C1-C18-alkyl; and wherein the alkyl groups represented by R1 and R2 optionally carry a hydroxy or amino substituent; and, optionally, a minor proportion of structural elements of the formula wherein R, R1, R2 and X may have the meaning as above, and Alk is a C1-C5-alkylene chain.

Abstract: A gas hydrate inhibitor includes, by weight, a copolymer including about 80 to about 95% of polyvinyl caprolactam (VCL) and about 5 to about 20% of N,N-dialkylaminoethyl(meth)acrylate or N-(3-dimethylaminopropyl) methacrylamide.

Abstract: The invention relates to the use of (A) esters of phosphoric acid and/or partial salts thereof with alkoxylated aliphatic, cycloaliphatic and/or aromatic alcohols and/or (B) fatty acid oligo-dialkanolamides as inhibitors against the formation of incrustations based on organic solids from liquid and/or gaseous hydrocarbon mixtures which are fluid and prone to form such incrustations. Preferred inhibitors having a surface-active character are capable of wetting, and especially of spreading on, solid work material surfaces also in the presence of the fluid hydrocarbon phase. They are particularly suitable as additives to crude oils and/or oil fractions susceptible of forming incrustations.

Abstract: A dispersion of an ester polymer in at least one liquid wherein the ester polymer is a polymer consisting essentially of a first monomer with structural units derived from at least one ester (1) of an aliphatic carboxylic acid with an aliphatic alcohol, wherein one of the acid and alcohol is ethylenically unsaturated and the other of the acid and alcohol has a long chain group of 14-40 carbons. A second monomer is optionally present which is a monomer derived from a different ester (2) within the same definition as ester (1), such that the mole average carbon content of the long chain group is 15-35, and a third monomer with structural units derived from a corresponding ester (3) of an aliphatic carboxylic acid and an aliphatic alcohol. One of the acid and alcohol is ethylenically unsaturated and the other has an aliphatic group of 1-13 carbons, such that at least 30% of the said aliphatic groups have 15-35 carbons.

Abstract: A method for controlling the formation of gas hydrate crystals in a fluid mixture by admixing with said fluid mixture a polyoxyalkylenediamine in an amount effective to prevent and/or inhibit crystal growth.

Abstract: The invention relates to iron control in an acid medium for forestalling the formation of precipitates known as “sludges” (asphaltic products) in contact with certain crude oils. Use is made of compounds comprising a mercaptan function, and, in combination, a selection of catalysts. Application to acid treatments for oil, gas, water, geothermal and analogous wells, as well as to industrial cleaning.

Abstract: A hydrate inhibitor comprising a blend of an additive (i) and at least one of an additive (ii) and an additive (iii) wherein additive (i) is a polymer of an ethylenically unsaturated N-heterocyclic carbonyl compound, with 6-8 ring atoms in the heterocyclic ring, additive (ii) is a corrosion inhibitor and additive (iii) is a salt of formula (I):[R1(R2)XR3]+Y− 1/v, I wherein each of R1, R2 and R3 is bonded directly to X, each of R1 and R2, which may be the same or different is an alkyl group of at least 4 carbons, X is S, NR4 or PR4, wherein each of R3 and R4 which may be the same or different represents hydrogen or an organic group, with the proviso that at least one of R3 and R4 is an organic group of at least 4 carbons, especially at least 5 carbons, and Y is an anion of valency v, wherein v is an integer of 1-4.

Abstract: A mutual solvent for use in oil and gas well operations comprising 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate and/or 2,2,4-trimethyl-1,3-pentanediol diisobutyrate, a coupling solvent, and an acid stable surfactant. The coupling solvent is selected from ethylene glycol monobutyl ether; diethylene glycol monobutyl ether; propylene glycol monomethyl ether acetate; propylene glycol monomethyl ether; C1-C5 alkyl alcohol; and mixtures thereof. The invention also relates to an emulsion for use in oil and gas well operations comprising an aqueous acid or acid-salt brine solution and the mutual solvent as described above. An emulsion according to the invention is stable, non-toxic, and effectively removes asphaltenic and paraffinic hydrocarbons from drilling equipment and oil and gas wells.

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 composition and method for acidizing a formation in the presence of ferric ion, free sulfur and/or sulfides is disclosed. The composition employs a ferric ion reducing agent and a sulfide reactant separately or in combination. The ferric ion reducing agent is a thioalkyl acid. The sulfide reactant compounds include &agr;-diketones and saturated and &agr;-unsaturated cyclic ketones. In another aspect, the reducing activity of the thioalkyl acid is accelerated by the presence of a catalytic quantity of a compound or mixture of compounds which yield in acid solution cuprous ion, cupric ion or combinations thereof with iodide ion.

Abstract: Solid, slowly dispersible well treatment composites are provided which have a sufficiently high melting point to prevent melting of the composite in hot weather. The composites have a low solubility and high specific gravity compared to prior art treatment agents; thus the composites readily sink in well and pipeline fluids and slowly release treatment ingredients over time, depending on the downhole and pipeline conditions. The composites include a nonylphenol ethoxylate having at least about 50 moles of ethylene oxide per mole of nonylphenol and a fatty acid amide having from 14-20 carbon atoms. Preferably, the composites further include a weighting agent and active ingredients selected from the group consisting of corrosion inhibitors, scale inhibitors, bactericides, scale converters, foaming agents, and mixtures thereof. In one embodiment, the composites are spherical in shape and are passed through pipelines for maintenance and treatment of the pipelines.

Abstract: Solid, slowly dispersible well treatment composites are provided which have a sufficiently high melting point to prevent melting of the composite in hot weather. The composites have a low solubility and high specific gravity compared to prior art treatment agents; thus the composites readily sink in well and pipeline fluids and slowly release treatment ingredients over time, depending on the downhole and pipeline conditions. The composites include a compound selected from the group consisting of nonylphenol ethoxylates having at least about 50 moles of ethylene oxide per mole of nonylphenol, fatty acid amides having from 14-20 carbon atoms, and mixtures thereof. Preferably, the composites further include a weighting agent and active ingredients selected from the group consisting of corrosion inhibitors, scale inhibitors, bactericides, scale converters, foaming agents, and mixtures thereof.

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 present invention relates to a synergistic mixture comprising, as asphaltene dispersant, from 5 to 95% by weight of a compound A of the formula I or II defined in the description, and from 5 to 95% by weight of a compound B of the formula (III) defined in the description, the substituents being defined as described in the description. The mixture is an excellent asphaltene dispersant in crude oils and products derived therefrom.

Abstract: The use of high flash point, low vapor pressure compositions for injection into, and coating of, gas and oil wells and surrounding underground hydrocarbon bearing formations and processing equipment for the purpose of removing scale, paraffins, tars, and other viscous constituents. Treatment results in increased flow of gas and/or oil and decreased adhesion of soils and scale in all aspects of oil and gas recovery, including hydrocarbon bearing formations, casings, lines, and pumping equipment. The composition contains about 40 to 99 wt. % of a fatty acid alkyl ester blend and about 1 to 25 wt. % of at least one lower alkyl glycol ether.

Abstract: A method of reducing the deposition of wax from a crude oil containing wax which comprises adding thereto at least one N-substituted polyalkylene imine which has at least one organic substituent that is a hydroxy-substituted alkyl group of 12-24 carbon atoms.

Abstract: An aqueous external dispersion comprising a wax dispersant and an organic crystal modifier composition dispersed through a continuous water phase is useful as a crystal modifier for petroleum or a petroleum-derived liquid. The dispersant comprises a non-ionic surfactant and is present in the dispersion in an amount sufficient to impart at least meta-stability to the dispersion. The dispersion has a viscosity at 25.degree. C. of less than about 50,000 centipoise.

Abstract: A wax and asphaltene solvation fluid for use in oil and gas wells is derived as a residual fluid from a feedstock that includes a greater mass percentage of trimethylbenzene than decane, and is preferably sour. Mass percentage of both aromatics and asphaltenes in the residual fluid is in the 30%-70% range, and a complex mixture of both is described.

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.

Abstract: A subterranean formation is treated to inhibit adsorption of asphaltenes by injecting a treatment fluid containing a sacrificial compound, such as a lignosulfonate. The lignosulfonate may be adsorbed onto formation surfaces in such a way as to act to inhibit the adsorption of asphaltenes. A pretreatment fluid for removing asphaltenes may be injected into the formation before the treatment fluid. The pretreatment fluid may contain an organic solvent, such as terpene.

Abstract: A process for the thermo-hydraulic control of gas hydrates in subsea production and injection wells as well as pipelines which transport liquid or gaseous hydrocarbons is described, the process making use of a Nitrogen Generating System foamed or in solution. The control may signify the prevention of the formation of the gas hydrates or the dissolution of the gas hydrate plug already formed. Under conditions of use designed for the prevention of the formation of gas hydrates the SGN fluid prevents the thermal conditions leading to the gas hydrate plugs. Under conditions of use designed to dissolve the already formed gas hydrate plugs, the SGN fluid alters the thermo-hydraulic conditions which favor the gas hydrate plugs, so that they are dissolved and return to the water+gas phase.

Abstract: New compositions and methods for inhibiting the formation and/or growth of gas hydrates are described. The compositions are generally polyether ammonium compounds of the formula:[R'R'R"N--(CHRCH.sub.2 (OCH.sub.2 CHR).sub.n NR'--).sub.m R'].sup.+ [X].sup.-where R=H or CH.sub.3 ;R'=H or C.sub.a H.sub.2a+1, where a=1 to 4;R"=C.sub.b H.sub.2b+1, where b=4 to 20;m=1 to 4;and n=2 to 6.The anion [X].sup.- may be freely substituted. Methods for inhibiting the formation and/or growth of gas hydrates involve treating fluid mixtures with the polyether ammonium compounds described.

Abstract: A process for transporting deaerated bitumen froth in a pipeline is described which comprises injecting water into the pipeline prior to deaerated bitumen froth injection to wet the interior walls of the pipeline. The deaerated bitumen froth is then injected into the pipeline at a critical velocity above 0.3 m/sec thereby initiating self-lubricating core-annular flow of the bitumen froth.

Abstract: A method is disclosed for mitigating fouling and reducing viscosity in primary fractionators and quench sections of ethylene plants by adding to a hydrocarbon stream a mono and/or a polyalkyl-substituted phenol-formaldehyde resin having a weight average molecular weight of from about 1,000 to about 30,000 and at least one alkyl substituent containing from about 4 to about 24 carbon atoms, which alkyl substituent may be linear or branched.

Abstract: Use of a mixture of at least one alkanolamide of general formula (I), wherein R is a hydrocarbon group having 7-23 carbon atoms, preferably 11-23 carbons atoms, A is an alkyleneoxy group having 2-4 carbon atoms and n is 2-12, preferably 2-8, and at least one alkoxylated alcohol in a weight ratio between the alkoxylated alkanolamide and the alkoxylated alcohol from 10:1 to 1:10, preferably in the range from 5:1 to 1:5 for producing a water-base liquid system with reduced flow resistance between the flowing, water-base liquid system and a solid surface.

Abstract: A method of transporting hydrates suspended in a fluid comprising water, a gas and a liquid hydrocarbon is described in which at least one non-ionic amphiphilic composition obtained by reacting at least one polymerized unsaturated vegetable oil with an aminoalcohol is incorporated into the fluid. The non-ionic amphiphilic composition is generally introduced in a concentration of 0.1% to 5% by weight with respect to the water.

Abstract: Alkylphosphonate ester compounds or acids thereof are disclosed as effective fouling inhibitors in liquid hydrocarbonaceous medium undergoing processing at elevated temperatures.

Abstract: A wax and asphaltene solvation fluid for use in oil and gas wells is derived as a residual fluid from a feedstock that includes a greater mass percentage of trimethylbenzene than decane, and is preferably sour. Mass percentage of both aromatics and asphaltenes in the residual fluid is in the 30%-70% range, and a complex mixture of both is described.

Abstract: An aqueous external dispersion comprising a wax dispersant and an organic crystal modifier composition dispersed through a continuous water phase is useful as a crystal modifier for petroleum or a petroleum-derived liquid. The dispersant comprises a non-ionic surfactant and is present in the dispersion in an amount sufficient to impart at least meta-stability to the dispersion. The dispersion has a viscosity at 25.degree. C. of less than about 50,000 centipoise.

Abstract: Formation of fouling deposits in a hydrocarbon process stream during processing at elevated temperatures is reduced by including in the hydrocarbon process stream an antifouling amount of a salt of a hydrocarbyl-substituted linked hydroxyaromatic compound, where the linked compound comprises at least two aromatic moieties.

Abstract: Gums and inorganic corrosion byproducts occurring in distilled petroleum fractions may be dispersed and resulting fouling controlled by adding to the petroleum distillate an effective dispersing amount of a monosubtituted alkylphenol polyethylenepolyamine-formaldehyde resin, such resins having a weight average molecular weight of from about 1,000 to about 10,000, and an alkyl substituent containing from about 4 to about 24 carbon atoms, which alkyl substituent may be a linear or branched.

Abstract: Glycine-N,N-diacetic acid derivatives and their alkali metal, akaline earth metal, ammonium and substituted ammonium salts, used as completing agents for alkaline earth metal and heavy metal ions in the production and transport of petroleum and natural gas.

Abstract: A method for controlling the formation of gas hydrate crystals in a fluid mixture by admixing with said fluid mixture a polyoxyalkylenediamine in an amount effective to prevent and/or inhibit crystal growth.

Abstract: A composition and method for acidizing a formation in the presence of ferric ion, free sulfur and/or sulfides is disclosed. The composition employs a ferric ion reducing agent and a sulfide reactant separately or in combination. The ferric ion reducing agent is a thioalkyl acid. The sulfide reactant compounds include .alpha.-diketones and saturated and .alpha.-unsaturated cyclic ketones. In another aspect, the reducing activity of the thioalkyl acid is accelerated by the presence of a catalytic quantity of a compound or mixture of compounds which yield in acid solution cuprous ion, cupric ion or combinations thereof with iodide ion.

Abstract: The present invention relates to an acid catalyzed thermal polycondensation process for producing amino acid polymers. More specifically, amino acid polymers are produced by thermally condensing a mixture of one or more amino acids and optionally one or more polyfunctional monomers, using an acid catalyst, while maintaining an intimate admixture. Processing techniques useful for maintaining an intimate admixture include adding to the mixture one or more processing aids, using mechanical means, and combinations thereof. The amino acid polymers produced by this process are useful as cleaning and detergent additives; fertilizer and pesticide additives; personal care product additives; dispersants for inorganic particulates, aqueous emulsions, and drilling muds; and water treatment and oil production operation additives as corrosion and scale inhibitors.

Abstract: The present invention relates to an acid catalyzed thermal polycondensation process for producing amino acid polymers. More specifically, amino acid polymers are produced by thermally condensing a mixture of one or more amino acids and optionally one or more polyfunctional monomers, using an acid catalyst, while maintaining an intimate admixture. Processing techniques useful for maintaining an intimate admixture include adding to the mixture one or more processing aids, using mechanical means, and combinations thereof. The amino acid polymers produced by this process are useful as cleaning and detergent additives; fertilizer and pesticide additives; personal care product additives; dispersants for inorganic particulates, aqueous emulsions, and drilling muds; and water treatment and oil.

Abstract: Asphaltenes may be dispersed in caustic treated petroleum crude oil, or in any fraction thereof by adding an effective dispersing amount of a mono or di substituted alkylphenol-formaldehyde resin and or a monosubstituted alkylphenol-polyethylenepolyamine-formaldehyde resin, such resins having a weight average molecular weight of from about 1,000 to about 20,000, and an alkyl substituent containing from about 4 to about 24 carbon atoms, which alkyl substituent may be linear or branched.

Abstract: Methods for removing paraffin wax deposits from the surfaces of oilfield production equipment during oil production by melting and subsequently dispersing the deposits. These methods utilize an acid compound and a neutralizer compound which react exothermally to melt the deposit and form a dispersant to remove the melted fragments of the deposit.

Abstract: A surface active composition for dispersing an oil in an aqueous media and/or for inhibiting deposition of oil on a surface of a water carrying system is disclosed. Preferably, the water carrying system is at least one system selected from the group consisting of a cooling tower, a cooling tower fill, means for heat exchange, means for industrial processing, and a body of water. A method for inhibiting deposition of an oil on a surface of a water carrying system is also provided.

Abstract: In accordance with the present invention, there is now provided a method for removing asphaltene deposits in a well environment such as the wellbore and near-wellbore regions, comprising the injection of deasphalted oil therein to solubilize the asphaltene deposits obstructing the well environment. More specifically, the method of the invention comprises the injection of deasphalted oil into the wellbore and the near-wellbore formation followed by a soaking period and a production period. The method of the present invention has the great advantage of readily dissolving precipitated asphaltene in a well environment without other costly treatments such as the use of solvents like xylene or toluene. Furthermore, the present method does not require the incorporation of any additives in the deasphalted oil.

Abstract: A method for conditioning a gas containing entrained asphaltene-containing hydrocarbons for pipeline transportation, having the steps of providing a stream of gas containing entrained asphaltene-containing hydrocarbons; and applying a surface active compound to the stream of gas, the surface active compound being a mixture of demulsifying agent, antifoaming agent, dispersant, aromatic solvent and alcohol solvent, whereby formation of emulsion from asphaltene containing hydrocarbons is prevented. The surface active compound has the following composition by volume: 5-15% demulsifying agent; 1-3% antifoaming agent; 10-40% dispersant; 10-60% aromatic solvent; and 20-60% alcohol solvent.

Abstract: Use of an alkoxylated alkanolamide of general formula (I), ##STR1## wherein R is a hydrocarbon group having 7-35 carbon atoms, preferably 9-23 carbon atoms, A is an alkyleneoxy group having 2-4 carbon atoms, and n is 2-20, preferably 3-12, for producing a water-base liquid system with reduced flow resistance between the flowing, water-base liquid system and a solid surface.

Abstract: Methods and compositions are provided for inhibiting the formation and deposition of pyrolytic coke on metal surfaces in contact with a hydrocarbon feedstock undergoing pyrolytic processing. Coke inhibition is achieved by adding a coke inhibiting amount of a combination of a boron compound and a dihydroxybenzene compound.