STRAY CURRENT CORROSION INHIBITOR

Description

TECHNICAL FIELD

The present disclosure generally relates to methods and compositions useful for inhibiting corrosion of metal surfaces. More particularly, the disclosure provides compositions and methods for inhibiting corrosion of metal surfaces caused by electric currents.

BACKGROUND

In oil and gas operations, power, voltage, and current play crucial roles in various processes and systems, such as casing, tubing, and pipeline operations. Some of the sources of voltage and current may include operational equipment (different equipment and systems in oil and gas production require varying levels of voltage and current, from low-voltage control systems to high-voltage motors and pumps) and cathodic protection systems, which use electrical currents to prevent corrosion of metal structures and require a controlled and consistent supply of voltage and current.

Stray currents are unintended currents that flow through unintended pathways due to grounding issues, insulation failures, or interference from nearby electrical systems. In oil and gas operations, stray currents can originate from faulty electrical insulation (damaged or degraded insulation can cause electrical leakage), grounding issues (poor or inadequate grounding of equipment can lead to unintended current paths) and interference (nearby electrical systems, such as high-voltage power lines or other industrial installations, can induce stray currents).

Problems within internal production casing, tubing, and pipeline resulting from stray current corrosion may include electrochemical corrosion (stray currents can accelerate corrosion by creating potential differences that drive electrochemical reactions), galvanic corrosion (differences in electrical potential between dissimilar metals in contact can cause galvanic corrosion, exacerbated by stray currents), integrity issues, structural damage (corrosion weakens the structural integrity of casings, tubing, and pipelines, leading to potential failures and leaks), leakage (compromised integrity due to corrosion or mechanical damage can result in fluid leakage, posing environmental and safety risks), operational disruptions including maintenance and repairs (frequent corrosion-related issues necessitate increased maintenance and repair efforts, disrupting production schedules) and equipment failures (electrical issues can cause equipment failures, impacting production efficiency and safety).

Common mitigation approaches to attend to the aforementioned problems associated with stray current corrosion include cathodic protection (both through sacrificial anodes and impressed current systems), insulation, and coatings. However, these approaches are costly and require considerable downtime to implement.

BRIEF SUMMARY

The present disclosure provides compositions and methods for inhibiting corrosion of metal surfaces caused by electric currents. In some embodiments, the disclosure provides a method of inhibiting corrosion of a metal surface in contact with a medium. The method comprises adding an effective amount of a composition to the medium, wherein the composition comprises a member selected from the group consisting of an organic sulfur compound, an organic sulfonic acid amine salt, a dicarboxylic acid diethanolamine salt, a fatty-amine condensate salt, a carboxylic acid-polyamine condensate, a carboxylic acid, and any combination thereof. The method also includes applying an electric current to the metal surface.

The foregoing has outlined rather broadly the features and technical advantages of the present disclosure in order that the detailed description that follows may be better understood. Additional features and advantages of the disclosure will be described hereinafter that form the subject of the claims of this application. It should be appreciated by those skilled in the art that the conception and the specific embodiments disclosed may be readily utilized as a basis for modifying or designing other embodiments for carrying out the same purposes of the present disclosure. It should also be realized by those skilled in the art that such equivalent embodiments do not depart from the spirit and scope of the disclosure as set forth in the appended claims.

DETAILED DESCRIPTION

Various embodiments are described below. The relationship and functioning of the various elements of the embodiments will be better understood in light of the following detailed description. However, elements and embodiments are not strictly limited to those explicitly described below.

Examples of methods and materials are described below, although methods and materials similar or equivalent to those described herein can be used in practice or testing of the present disclosure. All publications, patent applications, patents and other reference materials mentioned herein are incorporated by reference in their entirety. The materials, methods, and examples disclosed herein are illustrative only and not intended to be limiting.

Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. In case of conflict, the present document, including definitions, will control.

Unless otherwise indicated, an alkyl group as described herein alone or as part of another group is an optionally substituted linear or branched saturated monovalent hydrocarbon substituent containing from, for example, one to about sixty carbon atoms, such as one to about thirty carbon atoms, in the main chain. Examples of unsubstituted alkyl groups include methyl, ethyl, n-propyl, i-propyl, n-butyl, i-butyl, s-butyl, t-butyl, n-pentyl, i-pentyl, s-pentyl, t-pentyl, and the like.

The terms “aryl” or “ar” as used herein alone or as part of another group (e.g., arylene) denote optionally substituted homocyclic aromatic groups, such as monocyclic or bicyclic groups containing from about 6 to about 12 carbons in the ring portion, such as phenyl, biphenyl, naphthyl, substituted phenyl, substituted biphenyl or substituted naphthyl. The term “aryl” also includes heteroaryl functional groups. It is understood that the term “aryl” applies to cyclic substituents that are planar and comprise 4n+2 electrons, according to Huckel's Rule.

“Cycloalkyl” refers to a cyclic alkyl substituent containing from, for example, about 3 to about 8 carbon atoms, such as from about 4 to about 7 carbon atoms or about 4 to 6 carbon atoms. Examples of such substituents include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, and the like. The cyclic alkyl groups may be unsubstituted or further substituted with alkyl groups, such as methyl groups, ethyl groups, and the like.

“Heteroaryl” refers to a monocyclic or bicyclic 5- or 6-membered ring system, wherein the heteroaryl group is unsaturated and satisfies Huckel's rule. Non-limiting examples of heteroaryl groups include furanyl, thiophenyl, pyrrolyl, pyrazolyl, imidazolyl, 1,2,3-triazolyl, 1,2,4-triazolyl, isoxazolyl, oxazolyl, isothiazolyl, thiazolyl, 1,3,4-oxadiazol-2-yl, 1,2,4-oxadiazol-2-yl, 5-methyl-1,3,4-oxadiazole, 3-methyl-1,2,4-oxadiazole, pyridinyl, pyrimidinyl, pyrazinyl, triazinyl, benzofuranyl, benzothiophenyl, indolyl, quinolinyl, isoquinolinyl, benzimidazolyl, benzoxazolinyl, benzothiazolinyl, quinazolinyl, and the like.

Compounds of the present disclosure may be substituted with suitable substituents. The term “suitable substituent,” as used herein, is intended to mean a chemically acceptable functional group, preferably a moiety that does not negate the activity of the compounds. Such suitable substituents include, but are not limited to, halo groups, perfluoroalkyl groups, perfluoroalkoxy groups, alkyl groups, alkenyl groups, alkynyl groups, hydroxy groups, oxo groups, mercapto groups, alkylthio groups, alkoxy groups, aryl or heteroaryl groups, aryloxy or heteroaryloxy groups, aralkyl or heteroaralkyl groups, aralkoxy or heteroaralkoxy groups, HO—(C═O)-groups, heterocylic groups, cycloalkyl groups, amino groups, alkyl and dialkylamino groups, carbamoyl groups, alkylcarbonyl groups, alkoxycarbonyl groups, alkylaminocarbonyl groups, dialkylamino carbonyl groups, arylcarbonyl groups, aryloxycarbonyl groups, alkylsulfonyl groups, and arylsulfonyl groups. In some embodiments, suitable substituents may include halogen, an unsubstituted C₁-C₁₂ alkyl group, an unsubstituted C₄-C₆ aryl group, or an unsubstituted C1-C10 alkoxy group. Those skilled in the art will appreciate that many substituents can be substituted by additional substituents.

The term “substituted” as in “substituted alkyl,” means that in the group in question (e.g., the alkyl group), at least one hydrogen atom bound to a carbon atom is replaced with one or more substituent groups, such as hydroxy (—OH), alkylthio, phosphino, amido (—CON(R_A)(R_B), wherein R_A and R_B are independently hydrogen, alkyl, or aryl), amino(—N(R_A)(R_B), wherein R_A and R_B are independently hydrogen, alkyl, or aryl), halo (fluoro, chloro, bromo, or iodo), silyl, nitro (—NO₂), an ether (—OR_A wherein R_A is alkyl or aryl), an ester (—OC(O)R_A wherein R_A is alkyl or aryl), keto (—C(O)R_A wherein R_A is alkyl or aryl), heterocyclo, and the like.

When the term “substituted” introduces a list of possible substituted groups, it is intended that the term apply to every member of that group. That is, the phrase “optionally substituted alkyl or aryl” is to be interpreted as “optionally substituted alkyl or optionally substituted aryl.”

The terms “polymer,” “copolymer,” “polymerize,” “copolymerize,” and the like include not only polymers comprising two monomer residues and polymerization of two different monomers together, but also include (co)polymers comprising more than two monomer residues and polymerizing together more than two or more other monomers. For example, a polymer as disclosed herein includes a terpolymer, a tetrapolymer, polymers comprising more than four different monomers, as well as polymers comprising, consisting of, or consisting essentially of two different monomer residues. Additionally, a “polymer” as disclosed herein may also include a homopolymer, which is a polymer comprising a single type of monomer unit.

Unless specified differently, the polymers of the present disclosure may be linear, branched, crosslinked, structured, synthetic, semi-synthetic, natural, organic, inorganic, and/or functionally modified. A polymer of the present disclosure can be in the form of a solution, a dry powder, a liquid, or a dispersion, for example.

“Aqueous system” refers to any system containing one or more metal surfaces/components, which are in contact with an aqueous medium (e.g., water) on a periodic or continuous basis. The compositions and methods disclosed herein can be applied to any aqueous system.

“Aqueous industrial system” means any system that circulates an aqueous medium or a medium including water as a component. Non-limiting examples of “industrial aqueous systems” include cooling systems, boiler systems, heating systems, oil and gas systems, a petroleum well, a downhole formation, a geothermal well, a gas scrubber, an air washer, a water purification system, a clarification system, and any other system that circulates or includes water. The compositions and methods disclosed herein can be applied to any aqueous industrial system.

The present disclosure relates to corrosion inhibitor compounds, compositions, and methods of inhibiting corrosion caused by electric currents. Inhibiting corrosion includes, for example, reducing corrosion, completely eliminating corrosion or prohibiting corrosion from occurring for some period of time, lowering a rate of corrosion, etc.

The compositions and methods disclosed herein are useful for inhibiting corrosion of a metal surface in contact with a medium, wherein the medium comprises an electric current. Methods include adding an effective amount of a composition to the medium, wherein the composition comprises a member selected from the group consisting of an organic sulfur compound, an organic sulfonic acid amine salt, a dicarboxylic acid diethanolamine salt, a fatty-amine condensate salt, a carboxylic acid-polyamine condensate, a carboxylic acid, or any combination thereof.

The source of the electric is not particularly limited and the methods and compositions disclosed herein are effective regardless of the source of the electric current. As illustrative examples, the source of the electric current may be a low-voltage control system, a high-voltage motor and/or pump, a cathodic protection system, or any combination thereof.

A composition disclosed herein may include an organic sulfur compound. Illustrative, non-limiting examples of organic sulfur compounds include a mercaptoalkyl alcohol (such as 2-mercaptoethanol), thioglycolic acid, a thiosulfate, a thiol, a disulfide, dithiothreitol, 2-hydroxyethyl disulfide (2,2′-dithiodiethanol, bis(2-hydroxyethyl) disulfide).

The amount of organic sulfur compound in the composition is not particularly limited. For example, the composition may include from about 1 wt. % to about 50 wt. % of the organic sulfur compound, such as about 1 wt. % to about 40 wt. %, about 1 wt. % to about 30 wt. %, about 1 wt. % to about 20 wt. %, about 1 wt. % to about 15 wt. %, about 1 wt. % to about 10 wt. %, about 1 wt. % to about 5 wt. %, or about 1 wt. % to about 3 wt. %.

A composition disclosed herein may include an organic sulfonic acid amine salt. Illustrative, non-limiting examples of organic sulfonic acid amine salts include morpholine dodecylbenzenesulfonate, a dodecylbenzylsulfonic acid salt, a xylene sulfonic acid salt, or any combination thereof. In some embodiments, the amine salt includes a linear alkylbenzene sulfonate amine salts. Illustrative examples of amines include morpholine, pyridine, quinoline, polyalkylenepolyamine, mono, di, tri ethanolamine, diethylenetriamine, tetraethylenepentamine, and aminoethylethanolamine.

The amount of organic sulfonic acid amine salt in the composition is not particularly limited. For example, the composition may include from about 1 wt. % to about 50 wt. % of the organic sulfonic acid amine salt, such as about 1 wt. % to about 40 wt. %, about 1 wt. % to about 30 wt. %, about 1 wt. % to about 20 wt. %, about 1 wt. % to about 15 wt. %, about 1 wt. % to about 10 wt. %, about 1 wt. % to about 5 wt. %, or about 1 wt. % to about 3 wt. %.

A composition disclosed herein may include a dicarboxylic acid diethanolamine salt. An illustrative, non-limiting example of a dicarboxylic acid diethanolamine salt includes 2-cyclohexene-1-octanoic acid, 5(or 6)-carboxy-4-hexyl-, compound with 2,2'-iminobis(ethanol). The present disclosure is also intended to cover 5-(7-carboxyheptyl)-2-hexyl-3-cyclohexene-1-carboxylic acid (CAS No. 53980-88-4) or a salt thereof.

The amount of dicarboxylic acid diethanolamine salt in the composition is not particularly limited. For example, the composition may include from about 1 wt. % to about 50 wt. % of the dicarboxylic acid diethanolamine salt, such as about 1 wt. % to about 40 wt. %, about 1 wt. % to about 30 wt. %, about 1 wt. % to about 20 wt. %, about 1 wt. % to about 15 wt. %, about 1 wt. % to about 10 wt. %, about 1 wt. % to about 5 wt. %, or about 1 wt. % to about 3 wt. %.

A composition disclosed herein may include a fatty-amine condensate salt. An illustrative, non-limiting example of a fatty-amine condensate salt includes a reaction product of a polyalkylenepolyamine, tall oil fatty acid, and a linoleic acid dimer, with dodecyl benzene sulfonic acid (DDBSA) and a linoleic acid dimer.

The amount of fatty-amine condensate salt in the composition is not particularly limited. For example, the composition may include from about 1 wt. % to about 50 wt. % of the fatty-amine condensate salt, such as about 1 wt. % to about 40 wt. %, about 1 wt. % to about 30 wt. %, about 1 wt. % to about 20 wt. %, about 1 wt. % to about 15 wt. %, about 1 wt. % to about 10 wt. %, about 1 wt. % to about 5 wt. %, or about 1 wt. % to about 3 wt. %.

A composition disclosed herein may include a carboxylic acid-polyamine condensate. Illustrative, non-limiting examples of carboxylic acid-polyamine condensates include an imidazoline or a napthenic acid reaction product with diethylenetriamine and tall oil fatty acid. Alternatively, a naphthenic acid imidazoline may also be an option wherein the naphthenic acid is reacted with diethylenetriamine.

The amount of carboxylic acid-polyamine condensate in the composition is not particularly limited. For example, the composition may include from about 1 wt. % to about 50 wt. % of the carboxylic acid-polyamine condensate, such as about 1 wt. % to about 40 wt. %, about 1 wt. % to about 30 wt. %, about 1 wt. % to about 20 wt. %, about 1 wt. % to about 15 wt. %, about 1 wt. % to about 10 wt. %, about 1 wt. % to about 5 wt. %, about 1 wt. % to about 3 wt. %, or about 1 wt. % to about 2 wt. %.

A composition disclosed herein may include a carboxylic acid. Illustrative, non-limiting examples of carboxylic acids include 5-carboxy-4-hexyl-2-cyclohexene-octanoic acid, 6-carboxy-4-hexyl-2-cyclohexene-octanoic acid, tall oil fatty acid, trimeric C₁₈ unsaturated fatty acid, dimeric C₁₈ unsaturated fatty acid, C₁₈ mono fatty acid, or any combination thereof.

The amount of carboxylic acid in the composition is not particularly limited. For example, the composition may include from about 0.1 wt. % to about 50 wt. % of the carboxylic acid, such as about 0.1 wt. % to about 40 wt. %, about 0.1 wt. % to about 30 wt. %, about 0.1 wt. % to about 20 wt. %, about 0.1 wt. % to about 15 wt. %, about 0.1 wt. % to about 10 wt. %, about 0.1 wt. % to about 5 wt. %, about 0.1 wt. % to about 3 wt. %, about 0.1 wt. % to about 2 wt. %, about 0.1 wt. % to about 1 wt. %, about 0.5 wt. % to about 1 wt. %, about 0.5 wt. % to about 2 wt. %, about 0.5 wt. % to about 3 wt. %, or about 0.5 wt. % to about 5 wt. %.

A composition disclosed herein may include an oxyalkylate polymer. Illustrative, non-limiting examples of oxyalkylate polymers include polymers comprising oxyalkylated fatty amines and optionally one or more of acrylic acid, t-butylphenol, formaldehyde, maleic anhydride, ethylene oxide, propylene oxide, 4-nonylphenol, a phenolic and epoxide resin, an oxyalkylated fatty amine, and any combination thereof.

The amount of oxyalkylate polymer in the composition is not particularly limited. For example, the composition may include from about 1 wt. % to about 50 wt. % of the oxyalkylate polymer, such as about 1 wt. % to about 40 wt. %, about 1 wt. % to about 30 wt. %, about 1 wt. % to about 20 wt. %, about 1 wt. % to about 15 wt. %, about 1 wt. % to about 10 wt. %, about 1 wt. % to about 5 wt. %, about 1 wt. % to about 3 wt. %, or about 1 wt. % to about 2 wt. %.

A composition disclosed herein may include a solvent. Illustrative, non-limiting examples of solvents include water, ethylene glycol, ethylene glycol monobutyl ether, kerosene, and any combination thereof.

The amount of solvent in the composition is not particularly limited. For example, the composition may include from about 10 wt. % to about 99 wt. % of the solvent, such as about 15 wt. % to about 99 wt. %, about 20 wt. % to about 99 wt. %, about 25 wt. % to about 99 wt. %, about 30 wt. % to about 99 wt. %, about 35 wt. % to about 99 wt. %, about 40 wt. % to about 99 wt. %, about 45 wt. % to about 99 wt. %, about 50 wt. % to about 99 wt. %, about 55 wt. % to about 99 wt. %, about 60 wt. % to about 99 wt. %, about 65 wt. % to about 99 wt. %, about 70 wt. % to about 99 wt. %, about 75 wt. % to about 99 wt. %, about 80 wt. % to about 99 wt. %, about 85 wt. % to about 99 wt. %, about 90 wt. % to about 99 wt. %, about 50 wt. % to about 95 wt. %, about 60 wt. % to about 95 wt. %, about 70 wt. % to about 90 wt. %, or about 80 wt. % to about 90 wt. %.

As an additional, illustrative example, a composition of the present disclosure may include from about 1 wt. % to about 5 wt. % of the organic sulfur compound, from about 1 wt. % to about 5 wt. % of the organic sulfonic acid amine salt, from about 1 wt. % to about 5 wt. % of the dicarboxylic acid diethanolamine salt, from about 1 wt. % to about 5 wt. % of the fatty-amine condensate salt, from about 0.5 wt. % to about 5 wt. % of the carboxylic acid-polyamine condensate, from about 0.1 wt. % to about 5 wt. % of the carboxylic acid, from about 0.1 wt. % to about 5 wt. % of the oxyalkylate polymer, and from about 65 wt. % to about 96 wt. % of the solvent.

In certain embodiments, a composition of the present disclosure comprises from about 2 wt. % to about 60 wt. % of the carboxylic acid, the fatty-amine condensate salt, and/or the dicarboxylic acid diethanolamine salt, from about 1 wt. % to about 15 wt. % of the organic sulfur compound and/or the organic sulfonic acid amine salt, and from about 50 wt. % to about 90 wt. % of the solvent.

In certain embodiments, the organic sulfur compound comprises 2-mercaptoethanol, the organic sulfonic acid amine salt comprises morpholine dodecylbenzenesulfonate, the dicarboxylic acid diethanolamine salt comprises 2-cyclohexene-1-octanoic acid, 5(or 6)-carboxy-4-hexyl-, compound with 2,2'-iminobis(ethanol), the fatty-amine condensate salt comprises a reaction product of a polyalkylenepolyamine, tall oil fatty acid, and a linoleic acid dimer, with dodecyl benzene sulfonic acid (DDBSA) and a linoleic acid dimer, the carboxylic acid-polyamine condensate comprises a napthenic acid reaction product with diethylenetriamine and tall oil fatty acid, the carboxylic acid comprises 5-carboxy-4-hexyl-2-cyclohexene-octanoic acid, the oxyalkylate polymer comprises an acrylic acid polymer comprising t-butylphenol, formaldehyde, maleic anhydride, ethylene oxide, propylene oxide, 4-nonylphenol, a phenolic and epoxide resin, and an oxyalkylated fatty amine, and the solvent comprises water.

In certain embodiments, a composition of the present disclosure includes a dicarboxylic acid, a dicarboxylic acid diethanolamine salt, a fatty-amine condensate, tall oil fatty acid, linoleic acid dimer, carboxylic acid-polyamine condensate, naphthenic acid reaction product with diethylenetriamine and tall oil fatty acid, naphthenic acid reaction product with diethylenetriamine, and any combination thereof. A composition of the present disclosure may include (or exclude) any one of the foregoing components or any combination of two, three, four, five, six, seven, or eight of the foregoing components. For example, a composition may include a dicarboxylic acid diethanolamine salt, a fatty-amine condensate salt, or a carboxylic acid-polyamine condensate. A composition may also include a combination of a dicarboxylic acid diethanolamine salt with a fatty-amine condensate salt, a combination of a dicarboxylic acid diethanolamine salt with a carboxylic acid-polyamine condensate, or a combination of a fatty-amine condensate salt with a carboxylic acid-polyamine condensate.

The compositions of the present disclosure may include (or exclude) one or more additional components and/or one or more additional components may be added to the medium and/or metal surface before, after, and/or with a composition of the present disclosure.

Illustrative, non-limiting examples of additional components include a fouling control agent, an additional corrosion inhibitor, a corrosion inhibitor intensifier, a biocide, a preservative, an acid, an anti-emulsifier, an iron chelating agent, a hydrogen sulfide scavenger, a surfactant, an asphaltene inhibitor, a paraffin inhibitor, a scale inhibitor, a gas hydrate inhibitor, a pH modifier, an emulsion breaker, a reverse emulsion breaker, a coagulant/flocculant agent, an emulsifier, a water clarifier, a dispersant, an antioxidant, a polymer degradation prevention agent, a permeability modifier, a foaming agent, an antifoaming agent, a CO₂ scavenger, an O₂ scavenger, a gelling agent, a lubricant, a friction reducing agent, a salt, a clay stabilizer, a bactericide, a salt substitute, a relative permeability modifier, a breaker, a fluid loss control additive, an iron control agent, a drag reducing agent, a flow improver, a viscosity reducer, and any combination thereof.

A hydrate inhibitor may include, for example, a mono-alkyl amide, a di-alkyl amide, an alkyl quaternary ammonium salt, and any combination thereof.

An asphaltene inhibitor may include, for example, an alkylphenol/formaldehyde resin, a polyisobutylene esters, a polyisobutylene imides, a polyalkyl acrylate, and any combination thereof.

A paraffin inhibitor may include, for example, a polyalkyl acrylate, an olefin/maleic anhydride polymer, and any combination thereof.

A biocide may include, for example, glutaraldehyde, tetrakis(hydroxymethyl)phosphonium sulphate, a quaternary ammonium compound, chlorine, hypochlorite, ClO₂, bromine, ozone, hydrogen peroxide, peracetic acid, peroxycarboxylic acid, peroxysulphate, dibromonitrilopropionamide, isothiazolone, terbutylazine, polymeric biguanide, methylene bisthiocyanate, and any combination thereof.

A scale inhibitor may include, for example, a phosphonate, a sulfonate, a phosphate, a phosphate ester, a polymer comprising a phosphonate or phosphonate ester group, a polymeric organic acid, a peroxycarboxylic acid, and any combination thereof. In some embodiments, the scale inhibitor may be selected from a compound comprising an amine and/or a quaternary amine, nitrilotriacetic acid (NTA), ethylenediaminetetraacetic acid (EDTA), DETA phosphonate, and any combination thereof.

In some embodiments, the scale inhibitor is an acid-based scale inhibitor, such as phosphonic acid. In some embodiments, the scale inhibitor comprises an anionic group. The anionic group may comprise, for example, a carboxylate group or a sulfate group. In some embodiments, the scale inhibitor may include a phosphorous atom, a phosphorous-oxygen double bond, and/or a phosphono group.

In some embodiments, the scale inhibitor is selected from the group consisting of hexamethylene diamine tetrakis (methylene phosphonic acid), diethylene triamine tetra (methylene phosphonic acid), diethylene triamine penta (methylene phosphonic acid), polyacrylic acid (PAA), phosphino carboxylic acid (PPCA), diglycol amine phosphonate (DGA phosphonate), 1-hydroxyethylidene 1,1-diphosphonate (HEDP phosphonate), bisaminoethylether phosphonate (BAEE phosphonate), 2-acrylamido-2-methyl-1-propanesulphonic acid (AMPS), and any combination thereof.

In certain embodiments, the scale inhibitor is a polymer comprising an anionic monomer. The anionic monomer may be selected from, for example, acrylic acid, methacrylic acid, vinyl sulfonic acid, vinyl phosphonic acid, maleic anhydride, itaconic acid, crotonic acid, maleic acid, fumaric acid, styrene sulfonic acid, and any combination thereof.

In some embodiments, the scale inhibitor is selected from a phosphonate, a sulfonate, a phosphate, a phosphate ester, a polymer, such as a polymer comprising a phosphonate or phosphonate ester group, a polymeric organic acid, a peroxycarboxylic acid, and any combination thereof.

The fouling control agent may comprise, for example, a quaternary compound.

The acid may comprise, for example, hydrochloric acid, hydrofluoric acid, citric acid, formic acid, acetic acid, or any combination thereof.

The hydrogen sulfide scavenger may comprise, for example, an oxidant, inorganic peroxide, chlorine dioxide, a C₁-C₁₀ aldehyde, formaldehyde, glyoxal, glutaraldehyde, acrolein, methacrolein, a triazine, or any combination thereof.

The additional corrosion inhibitor may comprise, for example, an imidazoline compound, a pyridinium compound, a quaternary ammonium compound, a phosphate ester, an amine, an amide, a carboxylic acid, a thiol, and any combination thereof.

The surfactant may be non-ionic, cationic, anionic, amphoteric, or zwitterionic.

The additional component may be added to the medium before, after, and/or with the corrosion inhibitor compound/composition. The amount of additional component added to the medium is not particularly limited. For example, from about 1 ppm to about 5,000 ppm of the additional component may be added to the medium, such as about 1 ppm to about 2,500 ppm, about 1 ppm to about 2,000 ppm, about 1 ppm to about 1,500 ppm, about 1 ppm to about 1,000 ppm, about 1 ppm to about 750 ppm, about 1 ppm to about 500 ppm, about 1 ppm to about 250 ppm, about 1 ppm to about 100 ppm, about 25 ppm to about 5,000 ppm, about 25 ppm to about 2,500 ppm, about 25 ppm to about 1,500 ppm, about 25 ppm to about 1,000 ppm, or about 25 ppm to about 500 ppm.

If a composition of the present disclosure comprises the additional component, the composition may comprise from, for example, about 0.1 wt. % to about 25 wt. % of the component, such as from about 0.1 wt. % to about 20 wt. %, about 0.1 wt. % to about 15 wt. %, about 0.1 wt. % to about 10 wt. %, about 0.1 wt. % to about 5 wt. %, about 1 wt. % to about 5 wt. %, about 1 wt. % to about 10 wt. %, about 1 wt. % to about 15 wt. %, about 5 wt. % to about 15 wt. %, or about 5 wt. % to about 20 wt. %.

The compositions, components, and/or compounds of the present disclosure may be added to a medium and/or they may be applied directly to a metal surface in the presence and/or absence of the medium.

If added to a medium, the amount of composition added to the medium is not particularly limited. For example, a composition disclosed herein may be added to the medium in an amount ranging from about 1 ppm to about 50,000 ppm, such as from about 1 ppm to about 25,000 ppm, from about 1 ppm to about 20,000 ppm, from about 1 ppm to about 15,000 ppm, from about 1 ppm to about 10,000 ppm, from about 1 ppm to about 5,000 ppm, from about 1 ppm to about 3,000 ppm, from about 1 ppm to about 2,000 ppm, from about 1 ppm to about 1,000 ppm, from about 1 ppm to about 750 ppm, from about 1 ppm to about 500 ppm, from about 1 ppm to about 250 ppm, from about 1 ppm to about 100 ppm, from about 1 ppm to about 50 ppm, from about 1 ppm to about 25 ppm, from about 1 ppm to about 20 ppm, from about 1 ppm to about 15 ppm, from about 1 ppm to about 10 ppm, or from about 1 ppm to about 5 ppm.

The compositions and/or compounds disclosed herein may be added to a medium and/or metal surface using a variety of different application methods known in the art. In some embodiments, the compositions and/or compounds may be added continuously or intermittently to the medium, either automatically or manually, by using, for example, chemical injection pumps. The addition may involve dripping, pouring, spraying, pumping, injecting, or otherwise adding the composition, compound, and/or optional component to the medium and/or the metal surface. In some embodiments, the composition may be heated, such as from about 30° C. to 100° C., prior to addition.

In some embodiments, the compounds and/or compositions may be applied to the metal surface, such as an inner wall of a pipeline, using a pig system. For example, a pig system may include a lead pig and a filming pig spaced apart axially from the lead pig to define an application storage space therebetween. The compounds and/or compositions may be located in the application storage space. Once both the lead pig and the filming pig are located in the pipeline, a force may be applied, for example, to the filming pig to move the lead pig and the filming pig in the lateral direction through the pipeline. In certain embodiments, the force is derived from a pressurized fluid, a mechanical actuator, a hydraulic actuator, an air compressor, or any combination thereof.

The lead pig may, for example, prepare the surface of the pipe by removing residue through mechanical scraping. As the filming pig travels behind the lead pig, it uniformly applies the composition and/or compound in the application storage space to the interior surface of the pipe.

A method of preparing a pipeline for application of an even layer of the composition and/or compound to the interior surface of the pipeline may include several steps. For example, the method may include inserting the lead pig into the pipe and adding the composition and/or compound to the pipe upstream of the lead pig. Next, the method includes inserting the filming pig into the pipe upstream of the composition and/or compound such that the composition and/or compound is located in the application storage space. Once the lead pig and the filming pig are in place, the method includes applying a force to the filming pig to cause the filming pig and the lead pig to move in the lateral direction through the pipeline. While traveling, the lead pig may clean an interior wall of the pipeline and the filming pig applies the composition and/or compound to the interior wall of the pipeline.

The lead pig and the filming pig may be added or removed from the pipeline by any means known in the art. For example, the pipeline may have bypass sections, e.g. a pig launch and a pig receiver, in fluid communication with the main pipe in order to launch and receive the lead and filming pigs. The pig launcher may be used to launch the lead pig and the filming pig into the pipe, while the pig receiver may be used to receive the lead pig and the filming pig after moving through the pipeline.

The pig receiver may include a sensor configured to detect when the lead and filming pigs arrive at the pig receiver section of the pipeline. The pig receiver section may have different valves to control pressurization of the pipeline in order to safely remove the pigs from the pipeline. Once the pigs are removed, the valves may be reopened to return the system to the original condition.

During application of a composition and/or compound of the present disclosure, a method disclosed herein may include reducing a flow rate of the process fluid within the pipeline while applying the composition. For example, the flow rate may be reduced by about 10% to about 75% of the standard operating flow rate. In some embodiments, the flow rate is reduced by about 15% to about 70%, about 20% to about 65%, about 25% to about 60%, or about 25% to about 50%.

The compositions and/or compounds disclosed herein can be added to a medium at various levels of water cut. For example, the water cut can be from about 0% to about 100% volume/volume (v/v), from about 1% to about 80% v/v, or from about 1% to about 60% v/v. The medium may be an aqueous medium that contains various levels of salinity. For example, the medium can have a salinity of about 0% to about 25%, about 1% to about 24%, or about 10% to about 25% weight/weight (w/w) total dissolved solids (TDS).

The methods, compounds, and compositions disclosed herein may be used in any industrial systems, such as an aqueous industrial system, as well as an industrial system that includes hydrogen-containing mediums and/or carbon dioxide-containing mediums. In some embodiments, the compositions, compounds, and methods of the present disclosure may be used to inhibit corrosion of a metal surface present in an oil and/or gas production well and/or pipeline.

The compositions, compounds, and methods disclosed herein can be applied in any industry where it is desirable to inhibit corrosion. For example, a composition can be applied to a gas or liquid produced or used in the production, transportation, storage, and/or separation of crude oil or natural gas.

The medium in which the compositions and/or compounds of the disclosure are introduced can be contained in and/or exposed to many different types of devices/components. For example, the medium may be contained in an apparatus that transports fluid or gas from one point to another, such as an oil and/or gas pipeline. The device/component may be part of an oil and/or gas refinery, such as a pipeline, a separation vessel, a dehydration unit, or a gas line. The medium may also be contained in and/or exposed to a device/component used in oil extraction and/or production, such as a wellhead.

In some embodiments, one or more of a pipeline, a heat exchanger, a storage vessel, a flowline, a downhole tubular, a casing, a tank (e.g., railroad tank car or a tank truck/tanker), a separator, or any combination thereof, comprises the metal surface, which contacts the medium.

In certain embodiments, a subterranean formation and/or a pipeline comprises the metal surface to be treated by a composition and/or compound of the present disclosure. Certain methods disclosed herein comprise adding a composition and/or compound disclosed herein to a medium that comprises the metal surface. Alternatively and/or additionally, the methods disclosed herein may comprise applying the composition and/or compound directly to the metal surface as opposed to, for example, adding to a liquid medium in contact with the metal surface. In some embodiments, the composition and/or compound may be applied to the interior wall of the pipeline when the interior wall is dry or substantially dry.

In some embodiments, the pipeline is intended to transport a liquid medium/process fluid, such as an aqueous medium or a medium comprising aqueous and non-aqueous liquids (e.g., an aqueous/hydrocarbon mixture produced from a subterranean reservoir), and the composition and/or compound is applied in the absence of the process fluid. The components of the process fluid may include, for example, water, hydrocarbons, brine, crude oil, refined oil, gas, liquefied natural gas, carbon dioxide, liquid hydrogen, and any combination thereof.

A medium of the present disclosure may comprise, for example, produced water, fresh water, seawater, municipal water, brackish water, recycled water, salt water, surface water, condensed water, cooling water, injection water, ground water, carbon dioxide, hydrogen, or any mixture thereof.

An aqueous medium may comprise, for example, water, gas, and/or a liquid hydrocarbon. The liquid hydrocarbon may be any type of liquid hydrocarbon including, but not limited to, crude oil, heavy oil, processed residual oil, bitminous oil, coker oils, coker gas oils, fluid catalytic cracker feeds, gas oil, naphtha, fluid catalytic cracking slurry, diesel fuel, fuel oil, jet fuel, gasoline, and kerosene. The medium may also comprise a refined hydrocarbon product.

A medium (e.g., a fluid and/or a gas) treated with a composition and/or compound of the present disclosure can be at any selected temperature, such as ambient temperature or an elevated temperature. For example, the medium (e.g., water, liquid hydrocarbon, gas, etc.) may be at a temperature of from about 40° C. to about 250° C. In some embodiments, the medium may be at a temperature of from about −50° C. to about 300° C., about 0° C. to about 200° C., about 10° C. to about 100° C., or about 20° C. to about 90° C.

The presently disclosed compounds, compositions, and methods can effectively inhibit corrosion of a surface comprising any metal or any combination of metals. For example, a metal surface to be treated by the compounds, compositions, and/or methods of the present disclosure may comprise steel, such as stainless steel or carbon steel.

Additional illustrative examples include iron, aluminum, zinc, chromium, manganese, nickel, tungsten, molybdenum, titanium, vanadium, cobalt, niobium, or copper. The metal surface may also comprise any combination of the foregoing metals and/or any one or more of boron, phosphorus, sulfur, silicon, oxygen, and nitrogen.

In some aspects of the present disclosure, a metal surface may comprise metallic-chrome steel, ferritic-alloy steel, austenitic-steel, precipitation-hardened steel, high-nickel steel, carbon steel, or a combination thereof.

The presently disclosed corrosion inhibitor compounds, compositions, and methods are useful for inhibiting corrosion of metal surfaces in contact with an electric current. Additionally, the medium may comprise additional corrodents, such as a metal cation, a metal complex, a metal chelate, an organometallic complex, an aluminum ion, an ammonium ion, a barium ion, a chromium ion, a cobalt ion, a cuprous ion, a cupric ion, a calcium ion, a ferrous ion, a ferric ion, a hydrogen ion, a magnesium ion, a manganese ion, a molybdenum ion, a nickel ion, a potassium ion, a sodium ion, a strontium ion, a titanium ion, a uranium ion, a vanadium ion, a zinc ion, a bromide ion, a carbonate ion, a chlorate ion, a chloride ion, a chlorite ion, a dithionate ion, a fluoride ion, a hypochlorite ion, an iodide ion, a nitrate ion, a nitrite ion, an oxide ion, a perchlorate ion, a peroxide ion, a phosphate ion, a phosphite ion, a sulfate ion, a sulfide ion, a sulfite ion, a hydrogen carbonate ion, a hydrogen phosphate ion, a hydrogen phosphite ion, a hydrogen sulfate ion, a hydrogen sulfite ion, an acid, such as carbonic acid, hydrochloric acid, nitric acid, sulfuric acid, nitrous acid, sulfurous acid, a peroxy acid, or phosphoric acid, ammonia, bromine, carbon dioxide, chlorine, chlorine dioxide, fluorine, hydrogen chloride, hydrogen sulfide, iodine, nitrogen dioxide, nitrogen monoxide, oxygen, ozone, sulfur dioxide, hydrogen peroxide, a polysaccharide, a metal oxide, sand, a clay, silicon dioxide, titanium dioxide, mud, a brine, an organic acid, an insoluble inorganic and/or organic particulate, an oxidizing agent, a chelating agent, an alcohol, and any combination of the foregoing.

The foregoing may be better understood by reference to the following examples, which are intended for illustrative purposes and are not intended to limit the scope of the disclosure or its application in any way.

EXAMPLES

To simulate the enhanced polarization of a metal surface caused by stray current effects, an external polarization through cyclic polarization was imparted onto a steel specimen after a protective film was established.

A standard bubble cell test was conducted in which after a 4 hour pre-corrosion period (i.e., under blank, chemical-free conditions), an inventive corrosion inhibitor composition was applied, either injected at about 100 ppm, about 500 ppm, about 800 ppm, or about 10,000 ppm (1% v/v) or batch treated (wherein the electrode was dipped into the inhibitor composition for about 15 seconds and left to drip for about 30 seconds to allow excess chemical to be removed for about 10 seconds before being replaced into the test cell).

The system was left for about 20 hours to allow the corrosion inhibitor film to reach equilibrium before a polarization scan was imposed at a rate of about 0.167 mv/s starting from −200 mV (versus open-circuit potential, i.e., from a cathodic potential) up to either +500 mV (versus open-circuit potential, i.e., anodic potential) or to a maximum current density of 5 mA cm⁻² before which the potential sweep direction was reversed and swept back to the open-circuit potential.

The corrosion inhibitor composition included from about 1 wt. % to about 5 wt. % of an organic sulfur compound (such as 2-mercaptoethanol), from about 1 wt. % to about 5 wt. % of an organic sulfonic acid amine salt (such as morpholine dodecylbenzenesulfonate), about 1 wt. % to about 5 wt. % of a dicarboxylic acid diethanolamine salt (such as 2-cyclohexene-1-octanoic acid, 5(or 6)-carboxy-4-hexyl-, compound with 2,2'-iminobis(ethanol)), about 1 wt. % to about 5 wt. % of a fatty-amine condensate salt (such as a reaction product of a polyalkylenepolyamine, tall oil fatty acid, and a linoleic acid dimer, with dodecyl benzene sulfonic acid (DDBSA) and a linoleic acid dimer), about 0.5 wt. % to about 5 wt. % of a carboxylic acid-polyamine condensate (such as a napthenic acid reaction product with diethylenetriamine and tall oil fatty acid), about 0.1 wt. % to about 5 wt. % of a carboxylic acid (such as 5-carboxy-4-hexyl-2-cyclohexene-octanoic acid), about 0.1 wt. % to about 5 wt. % of an oxyalkylate polymer (such as an acrylic acid polymer comprising t-butylphenol, formaldehyde, maleic anhydride, ethylene oxide, propylene oxide, 4-nonylphenol, a phenolic and epoxide resin, and an oxyalkylated fatty amine), and from about 65 wt. % to about 96 wt. % of a solvent (such as water).

A C1018 steel electrode was initially ground to a 600 grit finish and degreased before attaching to the working electrode of a linear polarization resistance (LPR) probe. An additional two Hastelloy electrodes, freshly ground to 600 grit finish and degreased, were attached to counter and reference electrodes. The brine used comprised distilled water containing about 3 wt. % sodium chloride and was saturated with carbon dioxide before and during the testing. Tests were carried out at about 175° F. and no hydrocarbon was used in the tests.

A standard bubble cell set-up was used in which a glass vessel with a closed lid and applicable ports was used to house approximately 1 L of the test brine along with the LPR probe, thermocouple for temperature control, sparge tube for carbon dioxide addition, and magnetic stir bar (approximately 2 inch rotated at approximately 100 rpm).

Standard LPR measurements were made for the first 24 hours to measure the corrosion rate in which the first 4 hours was without chemical. At four hours into the test assessment, the corrosion inhibitor composition was either injected at the applicable dose rate (i.e., 100 ppm, 500 ppm, 800 ppm, or 10,000 ppm (1% v/v)) or batch treated (the electrode was dipped into the inhibitor product for about 5 seconds and left to drip to allow excess chemical to be removed for about 10 seconds before being replaced into the test cell). A further 20 hours were allowed for the system and steel surface to reach equilibrium.

A cyclic polarization scan was then carried out where the potential was swept at a rate of about 0.167 mV/s starting from −200 mV (versus open-circuit potential, i.e. from a cathodic potential) up to either +500 mV (versus open-circuit potential, i.e. anodic potential) or to a maximum current density of 5 mA cm⁻² before which the potential sweep direction was reversed and swept back to the open-circuit potential.

Under the conditions assessed, the addition of the corrosion inhibitor composition at the dose rates considered inhibited the corrosion taking place on the steel surface from the blank, untreated case, which can be observed from the LPR general corrosion rates. The level of inhibition increased with increasing the dose rate. For example, 800 ppm, 10,000 ppm, and the batch treatment resulted in the base or blank corrosion rate without chemical being reduced from more than 100 mpy to 1 mpy or less, equating to more than 99% inhibition.

From the cyclic polarization, it can be seen that during the anodic portion, in which the steel surface is being polarized with external potential to simulate the polarization from stray current, it is seen that at 100 ppm of the corrosion inhibitor composition, the current density increases with increasing polarizing potential in the anodic direction with positive hysteresis seen from the reverse sweep, indicating a greater amount of current density and corrosion at the same overpotential after polarization. While an improvement is seen at 500 pm and 800 ppm doses, in which a lower current density was seen at the same anodic potentials compared with that at 100 ppm, the trend was similar. There was little difference in the scan data between 500 ppm and 800 ppm, showing a difference in inhibitory effect under nonapplied potentials (as seen in the LPR test assessments where the inhibition was greater at 800 ppm than at 500 ppm) and under polarized conditions.

Much higher concentrations of inhibitor were needed with an addition of 10,000 ppm (1% v/v) to produce an effect against high polarization potentials. There is a distinct difference in the polarization curve at 10,000 ppm (1% v/v) compared with lower dose rates whereby the current density starts to act independently of the applied potentials showing the formation of a more robust film compared with that formed at lower dose rates. There is still some positive hysteresis seen during the reverse sweep, indicating some localized/pitting effects (seen in the profilometryscan of the electrode surface after the test).

Batch treatment of the corrosion inhibitor composition showed the most effective application against high polarization potentials. Overall, the current densities at all anodic potentials after batch treatment were lower than using 10,000 ppm (1% v/v) of the corrosion inhibitor composition. The current density again acts independently of the applied potentials showing the formation of a robust film compared with that formed at lower dose rates. However, in this case, the hysteresis was negative with the current density being lower on the reverse sweep than the forward sweep indicating a more robust film without localized/pitting effects and which is consistent with the profilometry scan of the electrode surface after the test.

One of the unexpected and surprising results discovered by the inventors was the retardation of the current after polarizing the metal electrode after batch treatment with the corrosion inhibitor in which the current density on the reverse sweep of the polarization scan was lower than that on the forward sweep (i.e., negative hysteresis). This shows that a more tenacious and protective film was generated, which retarded the current/corrosion at the metal surface.

All of the compositions and methods disclosed and claimed herein can be made and executed without undue experimentation in light of the present disclosure. While this invention may be embodied in many different forms, there are described in detail herein specific preferred embodiments of the invention. The present disclosure is an exemplification of the principles of the invention and is not intended to limit the invention to the particular embodiments illustrated. In addition, unless expressly stated to the contrary, use of the term “a” is intended to include “at least one” or “one or more.” For example, “a metal surface” is intended to include “at least one metal surface” or “one or more metal surfaces.”

Any ranges given either in absolute terms or in approximate terms are intended to encompass both, and any definitions used herein are intended to be clarifying and not limiting. Notwithstanding that the numerical ranges and parameters setting forth the broad scope of the invention are approximations, the numerical values set forth in the specific examples are reported as precisely as possible. Any numerical value, however, inherently contains certain errors necessarily resulting from the standard deviation found in their respective testing measurements. Moreover, all ranges disclosed herein are to be understood to encompass any and all subranges (including all fractional and whole values) subsumed therein.

Any composition disclosed herein may comprise, consist of, or consist essentially of any element, component and/or ingredient disclosed herein or any combination of two or more of the elements, components or ingredients disclosed herein.

Any method disclosed herein may comprise, consist of, or consist essentially of any method step disclosed herein or any combination of two or more of the method steps disclosed herein.

The transitional phrase “comprising,” which is synonymous with “including,” “containing,” or “characterized by,” is inclusive or open-ended and does not exclude additional, un-recited elements, components, ingredients and/or method steps.

The transitional phrase “consisting of” excludes any element, component, ingredient, and/or method step not specified in the claim.

The transitional phrase “consisting essentially of” limits the scope of a claim to the specified elements, components, ingredients and/or steps, as well as those that do not materially affect the basic and novel characteristic(s) of the claimed invention.

Unless specified otherwise, all molecular weights referred to herein are weight average molecular weights and all viscosities were measured at 25° C. with neat (not diluted) polymers.

As used herein, the term “about” refers to the cited value being within the errors arising from the standard deviation found in their respective testing measurements, and if those errors cannot be determined, then “about” may refer to, for example, within 5%, 4%, 3%, 2%, or 1% of the cited value.

Furthermore, the invention encompasses any and all possible combinations of some or all of the various embodiments described herein. It should also be understood that various changes and modifications to the presently preferred embodiments described herein will be apparent to those skilled in the art. Such changes and modifications can be made without departing from the spirit and scope of the invention and without diminishing its intended advantages. It is therefore intended that such changes and modifications be covered by the appended claims.