Nanobubbles to stabilize scale control additives

Abstract

A variety of treatment fluids used in oil and gas operations include a scale control additive and other additives. The scale control additive can be incompatible with the other additives, for example when the scale control additive has a different charge than the other additives. This incompatibility can cause instability of the treatment fluid by causing aggregation of colloidal droplets that are held together by electrostatic attractive forces. The addition of nanobubbles in the treatment fluid can stabilize the fluid and make the scale control additive and other additives compatible with each other.

Description

NANOBUBBLES TO STABILIZE SCALE CONTROL ADDITIVESTechnical Field

[0001] Oil and gas treatment fluids can include scale control additives and other additives. Nanobubbles can be used to stabilize the scale control additives with the other additives in the fluids.Brief Description of the Figures

[0002] The features and advantages of certain embodiments will be more readily appreciated when considered in conjunction with the accompanying figures. The figures are not to be construed as limiting any of the preferred embodiments.

[0003] Fig. 1 is a diagram illustrating a stimulation system according to certain embodiments.

[0004] Fig. l is a diagram illustrating a well system in which a fracturing stimulation operation can be performed.Detailed Description of the Invention

[0005] Oil and gas hydrocarbons are naturally occurring in some subterranean formations. In the oil and gas industry, a subterranean formation containing oil and / or gas is referred to as a reservoir. A reservoir can be located under land or offshore. Reservoirs are typically located in the range of a few hundred feet (shallow reservoirs) to a few tens of thousands of feet (ultra-deep reservoirs). In order to produce oil or gas, a wellbore is drilled into a reservoir or adjacent to a reservoir. The oil, gas, or water produced from a reservoir is called a reservoir fluid.

[0006] As used herein, a “fluid” is a substance having a continuous phase that can flow and conform to the outline of its container when the substance is tested at a temperature of 71 °F (22 °C) and a pressure of one atmosphere "atm" (0.1 megapascals "MPa"). A fluid can be a liquid, gas, or supercritical fluid. A homogenous fluid has only one phase; whereas aheterogeneous fluid has more than one distinct phase. A colloid is an example of a heterogeneous fluid. A heterogeneous fluid can be a slurry, which includes a continuous liquid phase and undissolved solid particles as the dispersed phase; an emulsion, which includes a continuous liquid phase and at least one dispersed phase of immiscible liquid droplets; a foam, which includes a continuous liquid phase and a gas as the dispersed phase; or a mist, which includes a continuous gas phase and liquid droplets as the dispersed phase. As used herein, the term "base fluid" means the solvent of a solution or the continuous phase of a heterogeneous fluid and is the liquid that is in the greatest percentage by volume of a treatment fluid.

[0007] A well can include, without limitation, an oil, gas, or water production well, an injection well, a monitoring well, or a geothermal well. The well can also be a storage well where the permanent or temporary entrapment of industrial emissions containing gases such as carbon dioxide (CO2); other gases such as nitrogen oxides (NOx) or sulfur oxides (SOx); or halogenated gases such as fluorocarbons, oxygenated fluorocarbons, chlorocarbons, or other organo-halogenated small molecules (Ci to C5). As used herein, a “well” includes at least one wellbore. A wellbore can include vertical, inclined, and horizontal portions, and it can be straight, curved, or branched. As used herein, the term “wellbore” includes any cased, and any uncased, open-hole portion of the wellbore. A near-wellbore region is the subterranean material and rock of the subterranean formation surrounding the wellbore. As used herein, a “well” also includes the near-wellbore region. The near-wellbore region is generally considered to be the region within approximately 100 feet radially of the wellbore. As used herein, “into a subterranean formation” means and includes into any portion of the well, including into the wellbore, into the near-wellbore region via the wellbore, or into the subterranean formation via the wellbore.

[0008] A portion of a wellbore can be an open hole or cased hole. In an open-hole wellbore portion, a tubing string can be placed into the wellbore. The tubing string allows fluids to be introduced into or flowed from a remote portion of the wellbore. In a cased-hole wellbore portion, a casing is placed into the wellbore that can also contain a tubing string. A wellbore can contain an annulus. Examples of an annulus include but are not limited to the space between the wellbore and the outside of a tubing string in an open-hole wellbore; the space between the wellbore and the outside of a casing in a cased-hole wellbore; and the space between the inside of a casing and the outside of a tubing string in a cased-hole wellbore.

[0009] During wellbore operations, it is common to introduce a treatment fluid into the well. Examples of common treatment fluids include, but are not limited to, drilling fluids, spacer fluids, completion fluids, and stimulation fluids. As used herein, a treatment fluid is a fluid designed and prepared to resolve a specific condition of a well or subterranean formation, such as for stimulation, isolation, gravel packing, or control of gas or water coning. The term “treatment fluid” refers to the specific composition of the fluid as it is being introduced into a well. The word “treatment” in the term “treatment fluid” does not necessarily imply any particular action by the fluid.

[0010] There are a variety of treatment fluids used in oil and gas operations. Commonly used treatment fluids include drilling fluids, spacer fluids, cement compositions, workover fluids, enhanced recovery fluids, and stimulation fluids. Stimulation treatment fluids can include fracturing fluids and acidizing fluids. Stimulation techniques can be used to help increase or restore oil, gas, or water production. In hydraulic fracturing, a fracturing fluid, which can also be an acidizing fluid, is pumped at a sufficiently high flow rate and high pressure through the wellbore and into the near wellbore region to create or enhance a fracture in the subterranean formation. Creating a fracture means making a new fracture in the formation. Enhancing a fracture means enlarging a pre-existing fracture or fissure in the formation. Other oilfield treatment operations that utilize a scale control inhibitor are scale control operations, commonly referred to as scale inhibition squeeze, where a large concentration (e.g., 100,000 ppm) of a scale inhibitor is placed into a reservoir in a single stage; or management treatment operations in a tubular conduit referred to as a capillary where a continuous but very small amount of a scale inhibitor is carried out in a continuous manner, uninterrupted, for a prolonged or extended period of time to prevent the formation of scale.

[0011] Scale can build up on wellbore equipment, including tubulars and other metal surfaces. As used herein, the term “scale” means a deposit or coating formed on the surface of material, such as metal or rock. Scale is generally caused by precipitation due to a chemical reaction with the surface of the material, precipitation caused by chemical reactions, a change in pressure or temperature, or a change in the composition of a solution. Common inorganic scales are calcium carbonate, calcium sulfate, barium sulfate, strontium sulfate, iron sulfides, iron oxides, iron carbonate, lead sulfide, zinc sulfide, the various silicates and phosphates and other divalent or trivalent oxides, or any of a number of compounds that are insoluble or slightlysoluble in water. A treatment fluid can include a scale control additive also known as a scale inhibitor that reduces or prevents scale formation in a wellbore.

[0012] Other additives besides a scale control additive are also generally included in a treatment fluid. For example, viscosifiers used to increase the viscosity of the fluid; water- soluble salts; clay-control additives used to prevent sloughing, swelling of clays, or gumbo formation; friction reducers used to reduce friction when the treatment fluid is pumped at a high flow rate; acids used to lower the pH of the fluid; sludge preventing agents; and surfactants such as, penetrating surfactants, emulsion prevention surfactants, demulsifying surfactants, and cationic or amphoteric surfactants. The additives can be charged, for example, one additive may be positively charged and cationic and another additive can be negatively charged and anionic. One significant disadvantage is that the scale control additive can be incompatible or become unstable with other additives that are included in the treatment fluid. Moreover, additives with different charges (e.g., cationic and anionic) can be incompatible or unstable in the fluid. The additives’ functionality (i.e., the additive’s ability to perform its function) and efficiency are highly dependent on the stability of the combination of the ingredients in the treatment fluid. Incompatibility or instability of a scale control additive with other additives within the fluid leads to decreased functionality and efficiency.

[0013] Thus, there is a long-felt need for increasing the compatibility and stability of scale control additives in treatment fluids. It has been discovered that the inclusion of nanobubbles can increase the compatibility, stability, functionality, and efficiency of the scale control additive. The inclusion of nanobubbles can also increase the compatibility, stability, functionality, and efficiency of the other additives included in the treatment fluid. Some of the many advantages to the use of nanobubbles is that an increase in compatibility or stability of the scale control additive occurs, the concentration of one or more of the additives can be decreased compared to treatment fluids without the nanobubbles, and stabilizing additives may not be needed.

[0014] A treatment fluid can include: a base fluid; a scale control additive; an additive; and a plurality of nanobubbles.

[0015] Methods of treating a portion of a subterranean formation can include introducing the treatment fluid into the subterranean formation.

[0016] It is to be understood that the discussion of any of the embodiments regarding the treatment fluid or any ingredient in the treatment fluid is intended to apply to all of the method and composition embodiments without the need to repeat the various embodiments throughout. Any reference to the unit “gallons” means U.S. gallons.

[0017] The treatment fluid can be used in a variety of oil or gas operations. The treatment fluid can be, for example, a drilling fluid, a spacer fluid, a cement composition, a workover fluid, a stimulation fluid, or a scale inhibitor squeeze.

[0018] The treatment fluid can be a solution, a dispersion, a colloid, an emulsion, or an invert emulsion. The treatment fluid includes a base fluid. The base fluid can include dissolved materials or undissolved solids. The base fluid can include a hydrocarbon liquid, or an internal phase of the treatment fluid can include a hydrocarbon liquid. The hydrocarbon liquid can be selected from the group consisting of a fractional distillate of crude oil; a fatty derivative of an acid, an ester, an ether, an alcohol, an amine, an amide, or an imide; a saturated hydrocarbon; an unsaturated hydrocarbon; a branched hydrocarbon; a cyclic hydrocarbon; and any combination thereof. Crude oil can be separated into fractional distillates based on the boiling point of the fractions in the crude oil. An example of a fractional distillate of crude oil is diesel oil. The saturated hydrocarbon can be an alkane or paraffin. The paraffin can be an isoalkane (isoparaffin), a linear alkane (paraffin), or a cyclic alkane (cycloparaffin). The unsaturated hydrocarbon can be an alkene, alkyne, or aromatic. The alkene can be an isoalkene, linear alkene, or cyclic alkene. The linear alkene can be a linear alpha olefin or an internal olefin.

[0019] The base fluid or an internal phase of the treatment fluid can comprise water. The water can be selected from the group consisting of freshwater, seawater, brine, and any combination thereof in any proportion. The treatment fluid can further include a water-soluble salt. The water-soluble salt can be selected from the group consisting of sodium chloride, calcium chloride, calcium bromide, potassium chloride, potassium bromide, magnesium chloride, cesium chloride, cesium bromide, and any combination thereof. The treatment fluid can contain the water-soluble salt in a concentration in the range of about 5 to about 350 pounds per barrel (ppb) (19 to 1,353 kilograms per cubic meter "kg / m3") of the water.

[0020] According to any of the embodiments, the treatment fluid is a stimulation fluid. The stimulation fluid can be used for a stimulation operation such as a fracturing operationor matrix acidizing operation. In matrix acidizing, the treatment fluid is introduced into the portion of the subterranean formation to be stimulated below the fracture gradient of that portion; and thus, does not create fractures in that portion. In a fracturing operation, the treatment fluid is introduced into the portion of the subterranean formation to be stimulated at or above the fracture gradient of that portion. The treatment fluid can also be used in an acid washing operation.

[0021] In the case when the treatment fluid is used in a fracturing operation, the treatment fluid can further include proppant. As used herein, the term “proppant” means a multitude of solid, insoluble particles. The proppant can be naturally occurring, such as sand, or synthetic, such as a high-strength ceramic. Suitable proppant materials include, but are not limited to, sand (silica), walnut shells, sintered bauxite, glass beads, plastics, nylons, resins, other synthetic materials, and ceramic materials. Mixtures of different types of proppant can be used as well. The concentration of proppant in a fracture treatment fluid can be in any concentration customarily used, and can be, for example, in the range of from about 0.01 kilograms to aboutO.96 kilograms of proppant per liter of the base fluid (about 0.1 Ib / gal to about 8 Ib / gal). The size, sphericity, and strength of the proppant can be selected based on the actual subterranean formation conditions to be encountered during the fracture treatment operation.

[0022] The treatment fluid also includes the scale control additive. The scale control additive can be anionic. Examples of anionic scale inhibitors as the scale control additive include but are not limited to, metalated versions of the additives listed above (f.g., EDTA-Na4; sodium polyacrylate, PMIDA-Na?; etc. aminopolycarboxylic acid comprising a phosphonoalkyl moiety such as N-(phosphonomethyl) iminodiacetic acid (PMIDA, N-(carboxymethyl)-N- (phosphonom ethyl )gly cine, glycine, N,N'-l,2-ethanediylbis(N-(phosphonomethyl), glyphosine; aminotrimethylene phosphonic acid, sodium aminotri s(m ethyl enephosphonate), N-(2- hydroxyethyl)iminobis (methylphosphonic acid), P, P'-((2 -propen-1 -ylimino)bis(methylene))bis-, phosphonic acid, P,P',P"-(nitrilotris(methylene))tris-, (nitrilotris(methylene))trisphosphonic acid, ((methylimino)_,dimethylene)bisphosphonic acid, phosphonic acid, P,P',P",P"'-(oxybis(2,l- ethanediylnitrilobis (methylene))tetrakis-, ((propylimino)bis(methylene))diphosphonic acid,P,P',P"-(nitrilotris(methylene))tris-, (ethylenedinitrilo)-tetramethylenephosphonic acid, ethylene- bis(nitrilodimethylene)tetraphosphonic acid, (ethylenebis(nitrilobis(methylene)))tetrakisphosphonic acid, tetrasodium tetrahydrogen (ethane- l,2-diylbis(nitrilobis(methylene)))tetrakisphosphonate, 6-(bis(phosphonomethyl)amino)hexanoic acid, (phenylmethyl)imino)bis_,(methylene)bisphosphonic acid, phosphonobutane tricarboxylic acid, 2-hydroxyphosphono dicarboxylic acid, or combinations thereof. Additionally, pentazinc; [bis[2-[bis(phosphonomethyl)amino]ethyl]amino] methylphosphonic acid, pentanickel; [bis[2-[bis(phosphonomethyl)amino] ethyl]amino] methylphosphonic acid, pentacadmium; [bis[2- [bis(phosphonomethyl)amino]ethyl]amino]methylphosphonic acid, pentamanganese; [bi s[2- [bis(phosphonomethyl)amino]ethyl]amino]methylphosphonic acid, nitrilotri(methylphosphonic acid), n,n-bis(phosphonomethyl)glycine, iminodi(methylphosphonic acid), (aminomethyl)phosphonic acid, methylenediphosphonic acid, diethylenetriaminepentakis(methylphosphonic acid), 2-hydroxyethyl imino bis(methylene)) bisphosphonic acid, amino-tris(methylenephosphonate), poly(vinyl phosphonic acid), sulfosuccinic acid, benzene sulfonic acid, naphthalene sulfonic acid, vinyl sulfonic acid, poly vinyl sulfonic acid, styrene sulfonic acid, polystyrene sulfonic acid, polyacrylic acid, hydroxypolycarboxylic acids such as citric acid, itaconic acid, hydroxy-carboxylic acid glycolic acid, lactic acid, polyhydroxy carboxylic acid gluconic acid maleic acid, , polyhydroxy polycarboxylic acid glucaric acid, tartaric acid, and monovalent salts thereof and any combination thereof.

[0023] Under certain circumstances there is the need to rely on non-anionic scale inhibitors. Examples of non-anionic scale inhibitors, which are largely dependent on the pH of the treatment fluid and the specific rock substrate, that can function as the scale control additive include but are not limited to natural scale inhibitors and polymeric scale inhibitors. Natural scale inhibitors are not limited to starch, cellulose, inulin, pig leaf extract, Herniaria glabra extract, and olive oil extract. Polymeric scale inhibitors comprise macromolecules in excess of 5,000 g / mol molecular weight up to 2,000,000 g / mol having a combination of functional groups that confer cationic, anionic, or both types of charges to the macromolecules. Examples of polymeric scale control agents include N-phosphonomethylated polymers containing an alkylenediamine or multiplicities of such that utilize pluri(alkylene)-multiamine, and sulfonated pendant groups and carboxylate groups, or quaternized n-alkyl groups.

[0024] Alternatively, a scale inhibitor can be a compositions of one or more species including N,N-bis(phosphonomethyl) cysteic acid; N,N-bis(phosphonomethyl) glycine; N5N- bis(phosphonom ethyl) taurine; N,N-bis(phosphonomethyl) cysteic acid; N,N- bis(phosphonom ethyl) glycine, or fully substituted (phosphonomethylated) analogues of theamino acids cysteine and glycine; phosphonomethyl amino acids which contain either carboxylic acid or sulfonic acid groups; N,N-bis(phosphonomethyl) L-glutamic acid; N,N- bis(phosphonomethyl) sulfanilic acid; N5N- bis(phosphonomethyl) aniline-2-sulfonic acid; (d) N,N-bis(phosphonom ethyl) L-serine and (e) N,N,N',N'-bis(phosphonomethyl) L-lysine; species N5N- bi s(phosphonom ethyl) L-glutamic acid or N,N-bis(phosphonomethyl) L-serine are the fully substituted (phosphonomethylated) analogues of the amino acids glutamic acid and serine, respectively, where each of these amino acids originally contains one primary amine group per molecule; species N,N,N',N'-bis(phosphonomethyl) L-lysine in the fully substituted (phosphonomethylated) analogue of the amino acid L-Lysine, where L- Lysine amino acid originally contains two primary amino groups per molecule.

[0025] The scale control additive can be a complexing or chelating agent. Chelating agents (also known as ligands or chelants) are materials that can be employed to control undesirable reactions of dissolved metal ions. In oilfield chemical treatments, chelating agents are frequently added to matrix stimulation fluids to prevent precipitation of total dissolved solids, for example from water-soluble salts. In addition, chelating agents can be used as components in many scale control formulations. Chelating agents form complexes with metal ions by forming coordinate bonds with the metal ion. Chelating agents sequester and inactivate the metal ion, so it does not easily react with other elements or ions to produce precipitates or scale; therefore, chelating agents can function as scale control additives when the pH of the fluid allows the chelating agent to function as a scale control additive. Chelating agents can also dissolve minerals without the use of a primary acid fluid comprised of a mineral or an organic acid, and can also dissolve scales (e. , calcium carbonate, magnesium carbonate, dolomite, and iron carbonate). The scale control additive can form a chelate complex or coordination complex containing one metal oxide and at least one polydentate or monodentate ligand. A chelate complex exists when a single metal ion forms coordinate bonds with a polydentate ligand. A ligand is commonly called a chelant, chelating agent, or sequestering agent. A coordination complex exists when a single metal ion forms coordinate bonds with a monodentate ligand. The ligand sequesters and inactivates the central metal ion, so the metal ion does not easily react with other elements or ions to produce precipitates or scale. A polydentate ligand is a molecule or compound in which at least two atoms of the ligand bond with the metal ion. A polydentate ligand can be, for example, bidentate (2 atoms bond), tridentate (3 atoms bond), tetradentate (4atoms bond), pentadentate (5 atoms bond), and so on. A monodentate ligand is a molecule or compound in which only one atom of the ligand bonds with the metal ion. The ligand can also contain at least one functional group that is capable of forming a bond with the metal ion (e.g., the free iron).

[0026] Examples of chelating agents include but are not limited to ethylenediaminetetraacetic acid (EDTA), hydroxy ethylethylenediaminetriacetic acid (HEDTA), methylglycinediacetic acid (MGDA), tetrasodium glutamate diacetate (GLDA), nitrilotriacetic acid (NTA), diethylenetriaminepentaacetic acid (DTP A), trans- 1,2-diaminocyclohexane- N,N,N’,N’ -tetraacetic acid (CDTA); ethylenedioxybis(ethyliminodi(acetic acid)) (EGTA); diethylenetriaminepentaacetic acid (DTP A), hydroxyethyliminodiacetate (HEIDA), iminodiacetic acid (IDA), triethylenetetramine-N,N,N„N”,N”„N”’-hexaacetic acid (TTHA) (and N,N’-bis(butanamide) derivative); 1,4,7, 10-tetraazacyclododecane- 1,4,7, 10-tetraacetic acid (DOT A); ethylenediamine-N,N’ -disuccinic acid (EDDS), hydroxyiminodisuccinic acid (HIDS) and monovalent salts thereof.

[0027] The scale control additive can be in a concentration in a range of 0.01 to 10 wt.% or 1 to 150,000 parts per million (ppm). It is to be understood that the concentration of the scale control additive need not be increased to control scale formation because the nanobubbles provide a mechanism whereby the scale control additive becomes compatible with the other additives in the treatment fluid.

[0028] The treatment fluid also includes a cationic additive in addition to the scale control additive. The cationic additive has an opposite charge from that of the scale control additive, such as an anionic scale control additive and the cationic additive. The combination of the scale control additive and the cationic additive can render the scale control additive incompatible in the treatment fluid and optionally also render the additive incompatible in the treatment fluid. By way of example, the scale control additive can be rendered incompatible by highly polarizable cationic species (e.g., hard acids, which are acids having a high charge to ionic radius ratio along with higher oxidation states), by high molecular weight and positively charged macromolecules, or when the total dissolved solids (TDS) are very high (i.e., greater than 100,000 ppm). As used herein, the term “incompatible” means the fluid does not form a stable homogenous mixture and it separates at a temperature of -20°C to 250° (-4°F to 482°F) within 24 hours. As used herein, the term “compatible” means the fluid forms a stablehomogenous mixture that does not separate at a temperature of -20°C to 250° (-4°F to 482°F) for 24 hours or longer. According to any of the embodiments, the treatment fluid can include more than one additive in addition to the scale control additive that are incompatible in the treatment fluid.

[0029] According to any of the embodiments, a test treatment fluid consisting of the base fluid, the anionic or non-ionic scale control additive, the cationic additive, and the nanobubbles and in the same proportions as the treatment fluid has less scale buildup than that of a control test treatment fluid consisting of only the base fluid, the anionic or non-ionic scale control additive, and the cationic additive and in the same proportions as the treatment fluid. That is, at the same concentration of the scale control additive, the nanobubbles allow the scale control additive to be more effective at controlling scale buildup than a fluid without the nanobubbles. A test treatment fluid can be used to determine the predicted performance of whether the nanobubbles provide the desired additive compatibility. As used herein, a “test treatment fluid” means a test fluid consisting of identical ingredients and in the same concentration as the treatment fluid. As used herein, a “control test fluid” means a fluid consisting of identical ingredients except without the nanobubbles and in the same concentration as the test treatment fluid. Different test treatment fluids can also be tested to determine the efficiency and performance of the additives with the nanobubbles compared to a control or other fluid without the nanobubbles that require a higher concentration of the additives to match the efficiency and performance of the test treatment fluids. It is to be understood that while the treatment fluid can contain other ingredients, it is the nanobubbles that are primarily or wholly responsible for providing the requisite compatibility of the additives in the base fluid. Therefore, it is not necessary for the treatment fluid to include other additives, such as stabilizing additives to provide the desired compatibility. It is also to be understood that any discussion related to a “test treatment fluid” or “control test treatment fluid” is included for purposes of demonstrating that the treatment fluid can contain other ingredients, but it is the nanobubbles that create the desirable additive compatibility. Therefore, while it may not be possible to perform a test in a wellbore for the specific treatment fluid being used, one can formulate a test treatment fluid to be tested in a laboratory to identify if the ingredients and concentration of the ingredients will provide the stated compatibility.

[0030] Incompatibility between the scale control additive and the cationic additive can be seen through coacervate formation or agglomeration. Coacervate is an aqueous phase rich in macromolecules such as synthetic polymers that can include an aggregate of colloidal droplets held together by electrostatic attractive forces. Agglomeration is when two or more of the additives collect together in a mass. Accordingly, when the scale control additive and the additive have opposite charges, coacervation is likely to occur, which renders the additives incompatible and can lead to an unstable treatment fluid, among other negative effects.

[0031] The cationic additive can be a clay control additive. Some subterranean formations can be adversely affected by certain types of drilling fluids. One example of such a formation is a water-sensitive formation. When a drilling fluid contains water, and the water comes in contact with a water-sensitive formation, the water can adversely affect the subterranean formation. Some of the adverse effects can include swelling or sloughing of the subterranean formation, or gumbo formation. A clay control or clay stabilizing additive can help control clay in the subterranean formation from swelling or sloughing or gumbo formation. Examples of clay control additives can include but are not limited to poly- (2- (Acryloyloxy)ethyl)trimethylammonium chloride (polyAETAC), polydiallyldimethylammonium chloride (polyDADMAC), (Poly(3-(trimethylaminium)-2-hydroxy-A,A-dimethyl-A-propylpran- / -aminium dichloride methacrylamide)), (1,3-Propanediaminium, 2-hydroxy-A7, N1, N1, N3, Af?-hexamethyl-, chloride, choline chloride, chitosan, polyethyleneimine (PEI), or inorganic salts such as sodium chloride, potassium chloride, salts including mono-valent cations and counter-anions such as chloride, bromide, iodide, acetate, or formate, tetramethyl ammonium chloride (TMAC), ammonium chloride, or ammonium acetate.

[0032] The cationic additive can be a synthetic polymer, for example as a viscosifier, friction reducer, drag reducer, gelling agent, loss circulation agent, well kill agent, diverting agent, relative permeability modifier, wellbore sealing agent, formation sealing agent, fines migration control agent, or crosslinking agent. A polymer is a molecule composed of repeating units, typically connected by covalent chemical bonds. A polymer is formed from monomers. During the formation of the polymer, some chemical groups can be lost from each monomer. The piece of the monomer that is incorporated into the polymer is known as the repeating unit or monomer residue. The backbone of the polymer is the continuous link between the monomer residues. The polymer can also contain pendant functional groups connected to the backbone atvarious locations along the backbone. Polymer nomenclature is generally based upon the type of monomer residues comprising the polymer. A polymer formed from one type of monomer residue is called a homopolymer. A polymer formed from two or more different types of monomer residues is called a copolymer. The number of repeating units of a polymer is referred to as the chain length of the polymer. The number of repeating units of a polymer can range from approximately 11 to greater than 10,000. In a copolymer, the repeating units from each of the monomer residues can be arranged in various manners along the polymer chain. For example, the repeating units can be random, alternating, periodic, or block. The conditions of the polymerization reaction can be adjusted to help control the average number of repeating units (the average chain length) of the polymer. Polymer molecules can be cross-linked. As used herein, a “cross-link” and all grammatical variations thereof is a bond between two or more polymer molecules. Cross-linked polymer molecules can form a polymer network.

[0033] A polymer has an average molecular weight, which is directly related to the average chain length of the polymer. The average molecular weight of a polymer has an impact on some of the physical characteristics of a polymer, for example, its solubility and its dispersibility. For a copolymer, each of the monomers will be repeated a certain number of times (number of repeating units). The average molecular weight (Mw) for a copolymer can be expressed as follows:where wxis the weight fraction of molecules whose weight is Mx.

[0034] The synthetic polymer as a friction reducer can be selected from polyester- based and polyacrylamide-based synthetic polymers and terpolymers such as a polyacrylamide, a polyacrylamide derivative, an acrylamide copolymer, an anionic acrylamide copolymer, a cationic acrylamide copolymer, a nonionic acrylamide copolymer, an amphoteric acrylamide copolymer, a polyacrylate, a polyacrylate derivative, a polymethacrylate, a polymethacrylate derivative, polyurethanes, polyethylene oxide, polypropylene oxide polymers, and any combination thereof. The synthetic polymer as a viscosifier or gelling agent can be selected from polysaccharide-based polymers such as guar, xanthan, diutan, chitosan, chitin, hydroxyethyl cellulose (HEC), carboxymethyl cellulose (CMC), hyperbranched polyglycerols(HydroxyPropyl Guar), or carboxymethyl hydroxypropyl guar (CMHPG). The synthetic polymer can be cross-linked with a cross-linking agent or an uncross linked polymer.

[0035] The cationic additive can be a viscoelastic surfactant (VES). Viscoelasticity is the property of materials that exhibit both viscous and elastic characteristics when undergoing deformation. Viscous materials resist shear flow and strain linearly with time when a stress is applied; whereas elastic materials strain when stretched and quickly return to their original state once the stress is removed. Viscoelastic materials have elements of both of these properties and, as such, exhibit time-dependent strain. The additive can be selected from viscoelastic surfactants having an anionic, cationic, or zwitterionic headgroup, including but not limited to, tallow amidoamine oxide, ethoxylated ammonium chloride, alkyl sulfates, alkyl ether sulfates, alkyl ester sulfonates, alpha olefin sulfonates, linear alkyl benzene sulfonates, branched alkyl benzene sulfonates, linear dodecylbenzene sulfonates, branched dodecylbenzene sulfonates, alkylbenzene sulfonic acids, dodecylbenzene sulfonic acid, sulfosuccinates, sulfated alcohols, ethoxylated sulfated alcohols, alcohol sulfonates, ethoxylated and propoxylated alcohol sulfonates, alcohol ether sulfates, ethoxylated alcohol ether sulfates, propoxylated alcohol sulfonates, sulfated nonyl phenols, ethoxylated and propoxylated sulfated nonyl phenols, sulfated octyl phenols, ethoxylated and propoxylated sulfated octyl phenols, sulfated dodecyl phenols, ethoxylated and propoxylated sulfated dodecyl phenols, quaternary amine compounds, amine oxide compounds, quad-diamines compounds, erucic dimethyl amidopropyl betaine, dicarboxylic coconut derived sodium salt, cocamidopropyl dimethylamine, cocamidopropyl betaine, alkylether hydroxypropyl sultaine, or amine oxide.

[0036] The cationic additive can be an acid such as hydrochloric acid, formic acid, or acetic acid, for example for use in an acidizing fluid. The cationic additive can also be selected from iron-control agents such as iron-reducing agents, mutual solvents, alcohols, acid diverters, corrosion inhibitors, wetting aids (potentially cationic), bactericides (potentially hydrophobic and cationic), and biocides (potentially cationic).

[0037] The cationic additive can be in a concentration typically used depending on the function of the additive and type of additive selected. It is to be understood that the concentration of the additive need not be increased to perform the additive’s function because the nanobubbles provide a mechanism whereby the scale control additive and the additive becomes compatible with the treatment fluid.

[0038] The treatment fluid can further include other additives. The other additives can be compatible with the treatment fluid. The other additives can include but are not limited to, a dispersing agent (potentially anionic), a tackifying agent (hydrophobic and potentially anionic), resins, proppant, oxygen scavengers, and oxidizers.

[0039] The treatment fluid also includes a plurality of nanobubbles. The nanobubbles are mechanically generated in the absence of any surfactants by mechanically agitating a gas with the base fluid prior to introduction or as the treatment fluid is being introduced into the subterranean formation. The nanobubbles can have a nanometer droplet resonance time of 24 days under ambient conditions (z.e., a temperature of 71°F (21.7°C) and a pressure of 1 atmosphere). The nanobubbles can have a mean diameter ranging from 50 to 500 nanometers (nm), more preferably, 50 to 400 nm. The nanobubbles can have a population ranging from 1 to 100 million nanometer-sized bubbles per milliliter of the base fluid. The gas used to form the nanobubbles can be selected from air, oxygen, carbon dioxide, nitrogen, a single type of hydrocarbon gas (e.g., methane or propane), a mixture of different types of hydrocarbon gases, hydrogen, inert gases such as argon, ammonia gas, or chlorine gas.

[0040] According to any of the embodiments, the treatment fluid may be a fluid that is not a foam. As used herein, a “foam” is a gas dispersed in a liquid and stabilized by a surfactant in a ratio such that its bulk density approaches that of gas rather than liquid. By contrast, the nanobubbles are an artifact of mechanical agitation and are sustained in the base fluid motion and droplet size without the use of a surfactant. Other key differences between a foam and the nanobubbles is the droplet size of the nanobubbles is smaller than the droplet size of a foam, and the physical phenomena for nanobubbles is attributed to Brownian motion, whereas the physical phenomena associated with foams is attributed to buoyancy.

[0041] As discussed above, the scale control additive and the additive are incompatible in the treatment fluid without the nanobubbles. For example, the scale control additive and the additive can create a coacervate or agglomeration of the additives whereby the fluid separates before 24 hours and does not result in a stable homogenous fluid. Such incompatibility can be the result of electrostatic attractive forces of the charge of the scale control additive and the opposite charge of the additive creating a mass of colloidal droplets held together. The nanobubbles can disrupt the electrostatic attractive forces and make the scale control additive and the additive compatible with the treatment fluid. Dissolution of the anionicadditive (e.g, either the scale control additive or the additive) and dissolution of the cationic additive (i.e., the additive that has the opposite charge from the anionic additive) into the nanobubble laden fluid can allow for full or partial neutralization of the charge(s) on the molecules, which most critically drive the agglomeration or coacervation in a fluid without the nanobubbles. Without being limited by theory, it is believed that the nanobubbles are charged species themselves, hypothetically providing an electric double layer, which results in finite compatibility of the scale control additive and the additive in solution. In essence, the oppositely charged additives are not exposed to one another in solution until the nanobubbles coalesce.

[0042] After introduction into the wellbore, the nanobubbles can coalesce, for example due to the temperature of the formation, until a sufficient number of the nanobubbles cavitate. Upon cavitation, the scale control additive and / or the additive are then freed up to perform their desired function, such as for scale control, increasing viscosity, surface wetting, stabilizing clays in the formation, etc. The methods can further include causing or allowing the nanobubbles to coalesce and cavitate. According to any of the embodiments, the plurality of nanobubbles coalesce and cavitate after a desired amount of time after introduction into the subterranean formation, for example, at a time when it is desirable for the scale control additive and the additive to function for their intended purpose.

[0043] The nanobubbles provide many advantages. One being creating a stable fluid wherein the scale control additive and other additives are compatible with each other. Another unique advantage is the nanobubbles provide an increased surface area for the scale control additive and the additive, which can mean the concentration of each additive can be decreased and still perform very effectively compared to a fluid without the nanobubbles.

[0044] A well system 10 of Fig. 1 can include a treatment fluid producing apparatus 20, a fluid source 30, a proppant source 40, and a pump and blender system 50 and resides at the surface at a well site where a well 60 is located. In certain embodiments, the treatment fluid producing apparatus 20 can combine additives with a fluid (c.g., liquid or substantially liquid) from fluid source 30, to produce a stimulation fluid that is used to stimulate a formation. The stimulation fluid can be a fluid for ready use in a stimulation treatment of the well 60 or a concentrate to which additional fluid is added prior to use in a stimulation treatment of the well 60. In other instances, the stimulation fluid producing apparatus 20 can be omitted and the stimulation fluid sourced directly from the fluid source 30.

[0045] The proppant source 40 can include a proppant for combining with a fracturing acidizing fluid. The system may also include additive source 70 that provides one or more additives (e.g. friction reducers, surfactants, corrosion inhibitors, viscosifiers, and / or other optional additives) to alter the properties of the treatment fracturing fluid.

[0046] The pump and blender system 50 can receive the treatment fluid and combine it with other components, including proppant from the proppant source 40 and / or additional additives from the additive source 70. The resulting mixture may be pumped into the well 60 under a pressure sufficient to create or enhance one or more fractures in a subterranean zone, for example, to stimulate production of fluids from the zone. The resulting mixture may also be pumped into the well 60 at a pressure less than the fracture pressure of the subterranean formation. The treatment fluid producing apparatus 20, fluid source 30, and / or proppant source 40 can each be equipped with one or more metering devices (not shown) to control the flow of fluids, proppant, and / or other compositions to the pumping and blender system 50. Such metering devices may permit the pumping and the blender system 50 to pull from one, some, or all of the different sources at a given time and may facilitate the preparation of treatment fluids using continuous mixing or “on-the-fly” methods.

[0047] The step of introducing any of the treatment fluids can comprise pumping the treatment fluid into the subterranean formation. Fig. 2 shows the well 60 during a fracturing operation in a portion of a subterranean formation 102. The fracturing operation can be performed, for example, using treatment fluids. The subterranean formation can be penetrated by a well. The step of introducing can also include introducing any of the treatment fluids into the well. The well includes a wellbore 104. The wellbore 104 extends from the surface 106, and the treatment fluid 108 is introduced into a portion of the subterranean formation 102. The wellbore 104 can include a casing 110 that is cemented or otherwise secured to the wellbore wall. The wellbore 104 can be uncased or include uncased sections. Perforations can be formed in the casing 110 to allow treatment fluids and / or other materials to flow into the subterranean formation 102. In cased wells, perforations can be formed using shaped charges, a perforating gun, hydro-jetting and / or other tools.

[0048] The well is shown with a work string 112. The pump and blender system 50 can be coupled to the work string 112 to pump the treatment fluid 108 into the wellbore 104. The work string 112 can include coiled tubing, jointed pipe, and / or other structures that allowfluid to flow into the wellbore 104. The work string 112 can include flow control devices, bypass valves, ports, and or other tools or well devices that control a flow of fluid from the interior of the work string 112 into the subterranean formation 102. For example, the work string 112 can include ports (not shown) located adjacent to the wellbore wall to communicate the treatment fluid 108 directly into the subterranean formation 102, and / or the work string 112 can include ports that are spaced apart from the wellbore wall to communicate the treatment fluid 108 into an annulus that is located between the outside of the work string 112 and the wall of the wellbore.

[0049] The well system can include one or more sets of packers 114 that create one or more wellbore intervals. According to some embodiments, the methods also include creating or enhancing one or more fractures within the subterranean formation using the treatment fluid. When the treatment fluid is introduced into wellbore 104 (e.g., in Fig. 2, the wellbore interval located between the packers 114) at a sufficient hydraulic pressure, one or more fractures 116 may be created in the subterranean formation 102. The proppant particulates in the treatment fluid may enter the fractures 116 where they may remain after the fluid flows out of the wellbore. The proppant can be placed into the one or more fractures during the step of introducing. The proppant can form a proppant pack within the one or more fractures.

[0050] An embodiment of the present disclosure is a treatment fluid comprising: a base fluid; an anionic or non-ionic scale control additive; a cationic additive; and a plurality of nanobubbles. Optionally, the scale control additive is compatible in a test treatment fluid consisting of the base fluid, the scale control additive, the additive, and the nanobubbles and in the same proportions as the treatment fluid; and wherein the scale control additive is incompatible in a control test treatment fluid consisting of only the base fluid, the scale control additive, and the additive and in the same proportions as the treatment fluid. Optionally, the scale control additive is a scale inhibitor. Optionally, the scale inhibitor is selected from the group consisting of EDTA-Na4, sodium polyacrylate, PMIDA-Na2, aminopolycarboxylic acid comprising a phosphonoalkyl moiety selected from N-(phosphonom ethyl) iminodiacetic acid (PMIDA, N-(carboxymethyl)-N-(phosphonomethyl)glycine, glycine, N,N'-l,2-ethanediylbis(N- (phosphonomethyl), glyphosine; aminotrimethylene phosphonic acid, sodium aminotri s(methylenephosphonate), N-(2-hydroxyethyl)iminobis (methylphosphonic acid), P,P'- ((2-propen-l-ylimino)bis(methylene))bis-, phosphonic acid, P,P',P"-(nitrilotris(methylene))tris-,(nitrilotris(methylene))trisphosphonic acid, ((methylimino)_,dimethylene)bisphosphonic acid, phosphonic acid, P,P',P",P'"-(oxybis(2,l-ethanediylnitrilobis_'(methylene))tetrakis-, ((propylimino)bis(methylene))diphosphonic acid, P,P',P"-(nitrilotris(methylene))tris-, (ethylenedinitrilo)-tetramethylenephosphonic acid, ethylene- bis(nitrilodimethylene)tetraphosphonic acid, (ethylenebis(nitrilobis(methylene)))tetrakisphosphonic acid, tetrasodium tetrahydrogen (ethane- l,2-diylbis(nitrilobis(methylene)))tetrakisphosphonate, 6-(bis(phosphonom ethyl) amino)hexanoic acid, ('phenylmethyl)imino)bis (niethylene)bisphosphonic acid, phosphonobutane tricarboxylic acid, 2-hydroxyphosphono dicarboxylic acid, or combinations thereof; pentazinc; [bis[2-[bis(phosphonomethyl)amino]ethyl]amino] methylphosphonic acid, pentanickel; [bis[2-[bis(phosphonomethyl)amino] ethyl]amino] methylphosphonic acid, pentacadmium; [bis[2-[bis(phosphonomethyl)amino]ethyl]amino]methylphosphonic acid, pentamanganese; [bis[2-[bis(phosphonomethyl)amino]ethyl]amino]methylphosphonic acid, nitrilotri(methylphosphonic acid), n,n-bis(phosphonomethyl)glycine, iminodi (methylphosphonic acid), (aminomethyl)phosphonic acid, methylenediphosphonic acid, diethylenetriaminepentakis(methylphosphonic acid), 2-hydroxyethyl imino bis(methylene)) bisphosphonic acid, amino-tris(methylenephosphonate), poly(vinyl phosphonic acid), sulfosuccinic acid, benzene sulfonic acid, naphthalene sulfonic acid, vinyl sulfonic acid, poly vinyl sulfonic acid, styrene sulfonic acid, polystyrene sulfonic acid, polyacrylic acid, hydroxypolycarboxylic acids selected from citric acid, itaconic acid, hydroxy-carboxylic acid glycolic acid, lactic acid, polyhydroxy carboxylic acid gluconic acid maleic acid, polyhydroxy polycarboxylic acid glucaric acid, tartaric acid, and monovalent salts thereof and any combination thereof; starch, cellulose, inulin, pig leaf extract, Hemiaria glabra extract, olive oil extract, N-phosphonomethylated polymers comprising an alkylenediamine utilizing pluri(alkylene)-multiamine, and sulfonated pendant groups and carboxylate groups, or quaternized n-alkyl groups, and combinations thereof. Optionally, the scale control additive is a chelating agent. Optionally, the chelating agent is selected from the group consisting of ethylenediaminetetraacetic acid (EDTA), hydroxy ethylethylenediaminetriacetic acid (HEDTA), methylglycinediacetic acid (MGDA), tetrasodium glutamate diacetate (GLDA), nitrilotriacetic acid (NTA), diethylenetriaminepentaacetic acid (DTP A), trans- 1,2-diaminocyclohexane- N,N,N’,N’ -tetraacetic acid (CDTA); ethylenedioxybis(ethyliminodi(acetic acid)) (EGTA);diethylenetriaminepentaacetic acid (DTP A), hydroxyethyliminodiacetate (HEIDA), iminodiacetic acid (IDA), triethylenetetramine-N,N,N,,N”,N”„N”’-hexaacetic acid (TTHA) (and N,N’-bis(butanamide) derivative); 1,4,7, 10-tetraazacyclododecane- 1,4,7, 10-tetraacetic acid (DOT A); ethylenediamine-N,N’ -disuccinic acid (EDDS), hydroxyiminodi succinic acid (HIDS), monovalent salts thereof, and any combination thereof. Optionally, the scale control additive is in a concentration in a range 1 to 150,000 parts per million of the treatment fluid. Optionally, the cationic additive is selected from the group consisting of a clay control additive, a synthetic polymer, a viscoelastic surfactant, an acid, an iron-control agent including iron-reducing agents, mutual solvents, alcohols, acid diverters, corrosion inhibitors, wetting aids, bactericides, biocides, and combinations thereof. Optionally, the clay control additive is selected from the group consisting of poly- (2-(Acryloyloxy)ethyl)trimethylammonium chloride (polyAETAC), poly diallyl dimethylammonium chloride (polyDADMAC), (Poly(3-(trimethylaminium)-2- hydroxy-;V -dimethyl- / V-propylpran- / -aminium dichloride methacrylamide)), (1,3- Propanediaminium, 2-hydroxy-TV7, N1, N1, N3, N3,N3-hexamethyl-, chloride, choline chloride, chitosan, polyethyleneimine (PEI), or inorganic salts such as sodium chloride, potassium chloride, salts including mono-valent cations and counter-anions, tetramethyl ammonium chloride (TMAC), ammonium chloride, ammonium acetate, and combinations thereof. Optionally, the synthetic polymer is a friction reducer selected from polyester-based and polyacrylamide-based synthetic polymers and terpolymers selected from a polyacrylamide, a polyacrylamide derivative, an acrylamide copolymer, a cationic acrylamide copolymer, a polyacrylate, a polyacrylate derivative, a polymethacrylate, a polymethacrylate derivative, polyurethanes, polyethylene oxide, polypropylene oxide polymers, and any combination thereof. Optionally, the synthetic polymer is a viscosifier or gelling agent selected from the group consisting of polysaccharide-based polymers selected from guar, xanthan, diutan, chitosan, chitin, hydroxyethyl cellulose (HEC), carboxymethyl cellulose (CMC), hyperbranched polyglycerols, hydroxypropyl guar (HPG), or carboxymethyl hydroxypropyl guar (CMHPG), and combinations thereof. Optionally, the plurality of nanobubbles have a nanometer droplet resonance time of 24 days under a temperature of 71 °F (21 ,7°C) and a pressure of 1 atmosphere. Optionally, the plurality of nanobubbles have a mean diameter ranging from 50 to 400 nanometers. Optionally, the plurality of nanobubbles have a population ranging from 1 to 100 million nanometer-sized bubbles per milliliter of the base fluid.

[0051] Another embodiment of the present disclosure is a method of treating a subterranean formation comprising introducing a treatment fluid into the subterranean formation, wherein the treatment fluid comprises: a base fluid; an anionic or non-ionic scale control additive; a cationic additive; and a plurality of nanobubbles. Optionally, the methods further comprise causing or allowing the nanobubbles to coalesce and cavitate after introduction into the subterranean formation. Optionally, the scale control additive is compatible in a test treatment fluid consisting of the base fluid, the scale control additive, the additive, and the nanobubbles and in the same proportions as the treatment fluid; and wherein the scale control additive is incompatible in a control test treatment fluid consisting of only the base fluid, the scale control additive, and the additive and in the same proportions as the treatment fluid. Optionally, the scale control additive is a scale inhibitor. Optionally, the scale inhibitor is selected from the group consisting of EDTA-Na4, sodium polyacrylate, PMIDA-Na2, aminopolycarboxylic acid comprising a phosphonoalkyl moiety selected from N-(phosphonom ethyl) iminodiacetic acid (PMIDA, N-(carboxymethyl)-N-(phosphonomethyl)glycine, glycine, N,N'-l,2-ethanediylbis(N- (phosphonomethyl), glyphosine; aminotrimethylene phosphonic acid, sodium aminotri s(methylenephosphonate), N-(2-hydroxyethyl)iminobis (methylphosphonic acid), P,P'- ((2-propen-l-ylimino)bis(methylene))bis-, phosphonic acid, P,P',P"-(nitrilotris(methylene))tris-, (nitrilotris(methylene))trisphosphonic acid, ((methylimino)_,dimethylene)bisphosphonic acid, phosphonic acid, P,P',P",P"'-(oxybis(2,l-ethanediylnitrilobis_,(methylene))tetrakis-, ((propylimino)bis(methylene))diphosphonic acid, P,P',P"-(nitrilotris(methylene))tris-, (ethylenedinitrilo)-tetramethylenephosphonic acid, ethylene- bis(nitrilodimethylene)tetraphosphonic acid, (ethylenebis(nitrilobis(methylene)))tetrakisphosphonic acid, tetrasodium tetrahydrogen (ethane- l,2-diylbis(nitrilobis(methylene)))tetrakisphosphonate, 6-(bis(phosphonomethyl) amino)hexanoic acid, (phenylmethyl)imino)bis_,(methylene)bisphosphonic acid, phosphonobutane tricarboxylic acid, 2-hydroxyphosphono dicarboxylic acid, or combinations thereof; pentazinc; [bis[2-[bis(phosphonomethyl)amino]ethyl]amino] methylphosphonic acid, pentanickel; [bis[2-[bis(phosphonomethyl)amino] ethyl]amino] methylphosphonic acid, pentacadmium; [bis[2-[bis(phosphonomethyl)amino]ethyl]amino]methylphosphonic acid, pentamanganese;[bis[2-[bis(phosphonomethyl)amino]ethyl]amino]methylphosphonic acid, nitrilotri(methylphosphonic acid), n,n-bis(phosphonomethyl)glycine, iminodi(methylphosphonicacid), (aminomethyl)phosphonic acid, methylenediphosphonic acid, diethylenetriaminepentakis(methylphosphonic acid), 2-hydroxyethyl imino bis(methylene)) bisphosphonic acid, amino-tris(methylenephosphonate), poly(vinyl phosphonic acid), sulfosuccinic acid, benzene sulfonic acid, naphthalene sulfonic acid, vinyl sulfonic acid, poly vinyl sulfonic acid, styrene sulfonic acid, polystyrene sulfonic acid, polyacrylic acid, hydroxypolycarboxylic acids selected from citric acid, itaconic acid, hydroxy-carboxylic acid glycolic acid, lactic acid, polyhydroxy carboxylic acid gluconic acid maleic acid, polyhydroxy polycarboxylic acid glucaric acid, tartaric acid, and monovalent salts thereof and any combination thereof; starch, cellulose, inulin, pig leaf extract, Hemiaria glabra extract, olive oil extract, N-phosphonomethylated polymers comprising an alkylenediamine utilizing pluri(alkylene)-multiamine, and sulfonated pendant groups and carboxylate groups, or quaternized n-alkyl groups, and combinations thereof. Optionally, the scale control additive is a chelating agent. Optionally, the chelating agent is selected from the group consisting of ethylenediaminetetraacetic acid (EDTA), hydroxy ethylethylenediaminetriacetic acid (HEDTA), methylglycinediacetic acid (MGDA), tetrasodium glutamate diacetate (GLDA), nitrilotriacetic acid (NTA), diethylenetriaminepentaacetic acid (DTP A), trans- 1,2-diaminocyclohexane- N,N,N’,N’ -tetraacetic acid (CDTA); ethylenedioxybis(ethyliminodi(acetic acid)) (EGTA); diethylenetriaminepentaacetic acid (DTP A), hydroxyethyliminodiacetate (HEIDA), iminodiacetic acid (IDA), triethylenetetramine-N,N,N,,N”,N”„N”’-hexaacetic acid (TTHA) (and N,N’-bis(butanamide) derivative); 1,4,7, 10-tetraazacyclododecane- 1,4,7, 10-tetraacetic acid (DOT A); ethylenediamine-N,N’ -disuccinic acid (EDDS), hydroxyiminodisuccinic acid (HIDS), monovalent salts thereof, and any combination thereof. Optionally, the scale control additive is in a concentration in a range 1 to 150,000 parts per million of the treatment fluid. Optionally, the cationic additive is selected from the group consisting of a clay control additive, a synthetic polymer, a viscoelastic surfactant, an acid, an iron-control agent including iron-reducing agents, mutual solvents, alcohols, acid diverters, corrosion inhibitors, wetting aids, bactericides, biocides, and combinations thereof. Optionally, the clay control additive is selected from the group consisting of poly- (2-(Acryloyloxy)ethyl)trimethylammonium chloride (polyAETAC), poly diallyldimethylammonium chloride (polyDADMAC), (Poly(3-(trimethylaminium)-2- hydroxy-;V,A-dimethy]-A-propylpran- / -aminium dichloride methacrylamide)), (1,3- Propanediaminium, 2-hydroxy-A7, N1, N1, N3, A5,AJ-hexamethyl-, chloride, choline chloride,chitosan, polyethyleneimine (PEI), or inorganic salts such as sodium chloride, potassium chloride, salts including mono-valent cations and counter-anions, tetramethyl ammonium chloride (TMAC), ammonium chloride, ammonium acetate, and combinations thereof. Optionally, the synthetic polymer is a friction reducer selected from polyester-based and polyacrylamide-based synthetic polymers and terpolymers selected from a polyacrylamide, a polyacrylamide derivative, an acrylamide copolymer, a cationic acrylamide copolymer, a polyacrylate, a polyacrylate derivative, a polymethacrylate, a polymethacrylate derivative, polyurethanes, polyethylene oxide, polypropylene oxide polymers, and any combination thereof. Optionally, the synthetic polymer is a viscosifier or gelling agent selected from the group consisting of polysaccharide-based polymers selected from guar, xanthan, diutan, chitosan, chitin, hydroxyethyl cellulose (HEC), carboxymethyl cellulose (CMC), hyperbranched polyglycerols, hydroxypropyl guar (HPG), or carboxymethyl hydroxypropyl guar (CMHPG), and combinations thereof. Optionally, the plurality of nanobubbles have a nanometer droplet resonance time of 24 days under a temperature of 71 °F (21.7°C) and a pressure of 1 atmosphere. Optionally, the plurality of nanobubbles have a mean diameter ranging from 50 to 400 nanometers. Optionally, the plurality of nanobubbles have a population ranging from 1 to 100 million nanometer-sized bubbles per milliliter of the base fluid.

[0052] Therefore, the present invention is well adapted to attain the ends and advantages mentioned as well as those that are inherent therein. The particular embodiments disclosed above are illustrative only, as the present invention may be modified and practiced in different but equivalent manners apparent to those skilled in the art having the benefit of the teachings herein. Furthermore, no limitations are intended to the details of construction or design herein shown, other than as described in the claims below. It is, therefore, evident that the particular illustrative embodiments disclosed above may be altered or modified and all such variations are considered within the scope and spirit of the present invention.

[0053] As used herein, the words “comprise,” “have,” “include,” and all grammatical variations thereof are each intended to have an open, non-limiting meaning that does not exclude additional elements or steps. While compositions, systems, and methods are described in terms of “comprising,” “containing,” or “including” various components or steps, the compositions, systems, and methods also can “consist essentially of’ or “consist of’ the various components and steps. It should also be understood that, as used herein, “first,” “second,” and “third,” areassigned arbitrarily and are merely intended to differentiate between two or more additives, etc., as the case may be, and does not indicate any sequence. Furthermore, it is to be understood that the mere use of the word “first” does not require that there be any “second,” and the mere use of the word “second” does not require that there be any “third,” etc.

[0054] Whenever a numerical range with a lower limit and an upper limit is disclosed, any number and any included range falling within the range is specifically disclosed. In particular, every range of values (of the form, “from about a to about b,” or, equivalently, “from approximately a to b,” or, equivalently, “from approximately a - b”) disclosed herein is to be understood to set forth every number and range encompassed within the broader range of values. Also, the terms in the claims have their plain, ordinary meaning unless otherwise explicitly and clearly defined by the patentee. Moreover, the indefinite articles “a” or “an,” as used in the claims, are defined herein to mean one or more than one of the element that it introduces. If there is any conflict in the usages of a word or term in this specification and one or more patent(s) or other documents that may be incorporated herein by reference, the definitions that are consistent with this specification should be adopted.

Claims

What is claimed is:

1. A treatment fluid comprising: a base fluid; an anionic or non-ionic scale control additive; a cationic additive; and a plurality of nanobubbles.

2. The treatment fluid according to claim 1, wherein the scale control additive is compatible in a test treatment fluid consisting of the base fluid, the scale control additive, the additive, and the nanobubbles and in the same proportions as the treatment fluid; and wherein the scale control additive is incompatible in a control test treatment fluid consisting of only the base fluid, the scale control additive, and the additive and in the same proportions as the treatment fluid.

3. The treatment fluid according to claims 1 or 2, wherein the scale control additive is a scale inhibitor.

4. The treatment fluid according to claim 3, wherein the scale inhibitor is selected from the group consisting of EDTA-Na4, sodium polyacrylate, PMIDA-Na2, aminopolycarboxylic acid comprising a phosphonoalkyl moiety selected from N-(phosphonomethyl) iminodiacetic acid (PMIDA, N-(carboxymethyl)-N-(phosphonomethyl)glycine, glycine, N,N'-l,2-ethanediylbis(N- (phosphonomethyl), glyphosine; aminotrimethylene phosphonic acid, sodium aminotri s(methylenephosphonate), N-(2-hydroxyethyl)iminobis (methylphosphonic acid), P,P'- ((2-propen-l-ylimino)bis(methylene))bis-, phosphonic acid, P,P',P"-(nitrilotris(methylene))tris-, (nitrilotris(methylene))trisphosphonic acid, ((methylimino)_,dimethylene)bisphosphonic acid, phosphonic acid, P,P',P",P"'-(oxybis(2,l-ethanediylnitrilobis_,(methylene))tetrakis-, ((propylimino)bis(methylene))diphosphonic acid, P,P',P"-(nitrilotris(methylene))tris-, (ethylenedinitrilo)-tetramethylenephosphonic acid, ethylenebi s(nitrilodimethylene)tetraphosphonic acid, (ethylenebis(nitrilobis(methylene)))tetrakisphosphonic acid, tetrasodium tetrahydrogen (ethane- l,2-diylbis(nitrilobis(methylene)))tetrakisphosphonate, 6-(bis(phosphonom ethyl) amino)hexanoic acid, (phenylmethyl)imino)bis_,(methylene)bisphosphonic acid,phosphonobutane tricarboxylic acid, 2-hydroxyphosphono di carboxylic acid, or combinations thereof; pentazinc; [bis[2-[bis(phosphonomethyl)amino]ethyl]amino] methylphosphonic acid, pentanickel; [bis[2-[bis(phosphonomethyl)amino] ethyl]amino] methylphosphonic acid, pentacadmium; [bis[2-[bis(phosphonomethyl)amino]ethyl]amino]methylphosphonic acid, pentamanganese; [bis[2-[bis(phosphonomethyl)amino]ethyl]amino]methylphosphonic acid, nitrilotri(methylphosphonic acid), n,n-bis(phosphonomethyl)glycine, iminodi(methylphosphonic acid), (aminomethyl)phosphonic acid, methylenediphosphonic acid, diethylenetriaminepentakis(methylphosphonic acid), 2 -hydroxy ethyl imino bis(methylene)) bisphosphonic acid, amino-tris(m ethyl enephosphonate), poly(vinyl phosphonic acid), sulfosuccinic acid, benzene sulfonic acid, naphthalene sulfonic acid, vinyl sulfonic acid, poly vinyl sulfonic acid, styrene sulfonic acid, polystyrene sulfonic acid, polyacrylic acid, hydroxypolycarboxylic acids selected from citric acid, itaconic acid, hydroxy-carboxylic acid glycolic acid, lactic acid, polyhydroxy carboxylic acid gluconic acid maleic acid, polyhydroxy polycarboxylic acid glucaric acid, tartaric acid, and monovalent salts thereof and any combination thereof; starch, cellulose, inulin, pig leaf extract, Herniaria glabra extract, olive oil extract, N-phosphonomethylated polymers comprising an alkylenediamine utilizing pluri(alkylene)-multiamine, and sulfonated pendant groups and carboxylate groups, or quaternized n-alkyl groups, and combinations thereof.

5. The treatment fluid according to claim 1, wherein the scale control additive is a chelating agent.

6. The treatment fluid according to claim 5, wherein the chelating agent is selected from the group consisting of ethylenediaminetetraacetic acid (EDTA), hydroxy ethylethylenediaminetriacetic acid (HEDTA), methylglycinediacetic acid (MGDA), tetrasodium glutamate diacetate (GLDA), nitrilotriacetic acid (NTA), diethylenetriaminepentaacetic acid (DTP A), trans- l,2-diaminocyclohexane-N,N,N’,N’- tetraacetic acid (CDTA); ethylenedioxybis(ethyliminodi(acetic acid)) (EGTA); diethylenetriaminepentaacetic acid (DTP A), hydroxyethyliminodiacetate (HEID A), iminodiacetic acid (IDA), triethylenetetramine-N,N,N„N”,N”„N”’ -hexaacetic acid (TTHA) (and N,N’-bis(butanamide) derivative); 1,4,7, 10-tetraazacyclododecane- 1,4,7, 10-tetraacetic acid(DOT A); ethylenediamine-N,N’-disuccinic acid (EDDS), hydroxyiminodisuccinic acid (HIDS), monovalent salts thereof, and any combination thereof.

7. The treatment fluid according to claim 1, wherein the scale control additive is in a concentration in a range 1 to 150,000 parts per million of the treatment fluid.

8. The treatment fluid according to claim 1, wherein the cationic additive is selected from the group consisting of a clay control additive, a synthetic polymer, a viscoelastic surfactant, an acid, an iron-control agent including iron-reducing agents, mutual solvents, alcohols, acid diverters, corrosion inhibitors, wetting aids, bactericides, biocides, and combinations thereof.

9. The treatment fluid according to claim 8, wherein the clay control additive is selected from the group consisting of poly- (2-(Acryloyloxy)ethyl)trimethylammonium chloride (polyAETAC), polydiallyldimethylammonium chloride (polyDADMAC), (Poly(3- (trimethylaminium)-2-hydroxy-A,A-dimethyl-A-propylpran- / -aminium dichloride methacrylamide)), (1,3-Propanediaminium, 2-hydroxy- , N1, N1, N3, A3, A3-hexamethyl-, chloride, choline chloride, chitosan, polyethyleneimine (PEI), or inorganic salts such as sodium chloride, potassium chloride, salts including mono-valent cations and counter-anions, tetramethyl ammonium chloride (TMAC), ammonium chloride, ammonium acetate, and combinations thereof.

10. The treatment fluid according to claim 8, wherein the synthetic polymer is a friction reducer selected from polyester-based and polyacrylamide-based synthetic polymers and terpolymers selected from a polyacrylamide, a polyacrylamide derivative, an acrylamide copolymer, a cationic acrylamide copolymer, a polyacrylate, a polyacrylate derivative, a polymethacrylate, a polymethacrylate derivative, polyurethanes, polyethylene oxide, polypropylene oxide polymers, and any combination thereof.

11. The treatment fluid according to claim 8, wherein the synthetic polymer is a viscosifier or gelling agent selected from the group consisting of polysaccharide-based polymers selected from guar, xanthan, diutan, chitosan, chitin, hydroxyethyl cellulose (HEC), carboxymethyl cellulose(CMC), hyperbranched polyglycerols, hydroxypropyl guar (HPG), or carboxymethyl hydroxypropyl guar (CMHPG), and combinations thereof.

12. The treatment fluid according to claim 1, wherein the plurality of nanobubbles have a nanometer droplet resonance time of 24 days under a temperature of 71 °F (21.7°C) and a pressure of 1 atmosphere.

13. The treatment fluid according to claim 1, wherein the plurality of nanobubbles have a mean diameter ranging from 50 to 400 nanometers.

14. The treatment fluid according to claim 1, wherein the plurality of nanobubbles have a population ranging from 1 to 100 million nanometer-sized bubbles per milliliter of the base fluid.

15. A method of treating a subterranean formation comprising: introducing a treatment fluid into the subterranean formation, wherein the treatment fluid comprises: a base fluid; an anionic or non-ionic scale control additive; a cationic additive; and a plurality of nanobubbles.

16. The method according to claim 15, wherein the scale control additive is compatible in a test treatment fluid consisting of the base fluid, the scale control additive, the additive, and the nanobubbles and in the same proportions as the treatment fluid; and wherein the scale control additive is incompatible in a control test treatment fluid consisting of only the base fluid, the scale control additive, and the additive and in the same proportions as the treatment fluid.

17. The method according to claims 15 or 16, wherein the scale control additive is a scale inhibitor or a chelating agent.

18. The method according to any one of claims 15 - 17, wherein the cationic additive is selected from the group consisting of a clay control additive, a synthetic polymer, a viscoelastic surfactant, an acid, an iron-control agent including iron-reducing agents, mutual solvents, alcohols, acid diverters, corrosion inhibitors, wetting aids, bactericides, and biocides, and combinations thereof.

19. The method according to any one of claims 15 - 18, wherein the plurality of nanobubbles have a mean diameter ranging from 50 to 400 nanometers.

20. The method according to any one of claims 15 - 19, further comprising causing or allowing the nanobubbles to coalesce and cavitate after introduction into the subterranean formation.

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