Nanobubble enhanced acidizing fluids

Abstract

A nanobubble-enhanced fluid to transport acid to a subterranean formation. The nanobubble-enhanced fluid generally comprises nanobubbles, an acid, and an additive. The acid may be an organic acid or a mineral acid. The additive may be a salt or brine, corrosion inhibitor, corrosion inhibitor intensifier, biocide, scale control additive, clay control additive, gel stabilizer, anti-oxidant, polymer degradation prevention additive, relative permeability modifier, surfactant, demulsifier, foaming agent, wetting agent, dispersant, flocculant, scavenger (e.g., H2S scavengers, CO2 scavengers, or O2 scavengers), gelling agent, iron control agent, chelating agent, complexing agent, sequestering agent, metal ion control additive, or combinations thereof.

Description

[0001] NANOBUBBLE ENHANCED ACIDIZING FLUIDS

[0002] TECHNICAL FIELD

[0003] The present disclosure relates generally to wellbore operations, and more particularly, to the use of nanobubbles to enhance transport of acids to subterranean formations.

[0004] BACKGROUND

[0005] Hydrocarbon resources are generally located in subterranean porous rock formations. Wells must be drilled in order to access these resources. Tn the recovery of oil from a subterranean hydrocarbon-bearing formation, primary recovery methods that utilize the natural formation pressure to extract the oil often result in recovering only a portion of the oil in the formation.

[0006] After primary recovery, further oil can also be extracted from the formation by injecting protic substances, i.e., acids, into the formation. Additionally, protic substances may be injected into the well before fracturing to improve oil recovery (i.e., acid spearhead) by cleaning the rock face. Further still, protic substances may be injected and used in acid fracturing to improve oil recovery by simultaneously cleaning the rock face during fracturing. Transport of such protic substances to the formation that serve to clean up the rock face of oily or hydrocarbon matter may be difficult due to corrosion of wellbore equipment and high surface tension impeding fluid reaction rates.

[0007] BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Illustrative examples of the present disclosure are described in detail below with reference to the attached drawing figures, which are incorporated by reference herein, and wherein:

[0009] FIG. 1 is a schematic illustrating a system of surface equipment for the preparation and delivery of an acidizing fluid to a wellbore in accordance with one or more examples described herein;

[0010] FIG. 2 is a schematic illustrating the placement of an acidizing fluid into a fracture in a subterranean formation in accordance with one or more examples described herein; and

[0011] FIG. 3 is a schematic illustrating the treatment of an injection well in accordance with one or more examples described herein. FIG. 4 illustrates the charge-shielding effect of the nanobubbles on molecules of the acidizing fluid.

[0012] The illustrated figures are only exemplary and are not intended to assert or imply any limitation with regard to the environment, architecture, design, or process in which different examples may be implemented.

[0013] DETAILED DESCRIPTION

[0014] The present disclosure relates generally to wellbore operations, and more particularly, to the use of nanobubbles to enhance transport of acids to subterranean formations.

[0015] In the following detailed description of several illustrative examples, reference is made to the accompanying drawings that form a part hereof, and in which is shown by way of illustration specific examples that may be practiced. These examples are described in sufficient detail to enable those skilled in the art to practice them, and it is to be understood that other examples may be utilized, and that logical structural, mechanical, electrical, and chemical changes may be made without departing from the spirit or scope of the disclosed examples. To avoid detail not necessary to enable those skilled in the art to practice the examples described herein, the description may omit certain information known to those skilled in the art. The following detailed description is, therefore, not to be taken in a limiting sense, and the scope of the illustrative examples are defined only by the appended claims.

[0016] Unless otherwise indicated, all numbers expressing quantities of ingredients, properties such as molecular weight, reaction conditions, and so forth used in the present specification and associated claims are to be understood as being modified in all instances by the term “about.” Accordingly, unless indicated to the contrary, the numerical parameters set forth in the following specification and attached claims are approximations that may vary depending upon the desired properties sought to be obtained by the examples of the present invention. At the very least, and not as an attempt to limit the application of the doctrine of equivalents to the scope of the claim, each numerical parameter should at least be construed in light of the number of reported significant digits and by applying ordinary rounding techniques. It should be noted that when “about” is at the beginning of a numerical list, “about” modifies each number of the numerical list. Further, in some numerical listings of ranges some lower limits listed may be greater than some upper limits listed. One skilled in the art will recognize that the selected subset will require the selection of an upper limit in excess of the selected lower limit.

[0017] In the following discussion and in the claims, the terms “including” and “comprising” are used in an open-ended fashion, and thus should be interpreted to mean “including, but not limited to.” Unless otherwise indicated, as used throughout this document, “or” does not require mutual exclusivity.

[0018] The terms uphole and downhole may be used to refer to the location of various components relative to the bottom or end of a well. For example, a first component described as uphole from a second component may be further away from the end of the well than the second component. Similarly, a first component described as being downhole from a second component may be located closer to the end of the well than the second component.

[0019] The terms upstream and downstream may be used to refer to the location of various components relative to one another in regards to the flow of a sample through said components. For example, a first component described as upstream from a second component will encounter a sample before the downstream second component encounters the sample. Similarly, a first component described as being downstream from a second component will encounter the sample after the upstream second component encounters the sample. As used herein the weight / volume percentage (“w / v”) is to be understood to mean grams / 100 milliliters.

[0020] The present disclosure relates generally to wellbore operations, and more particularly, to the use of an acidizing fluid comprising nanobubbles to improve transportation of the acidizing fluid to the subterranean formation. Acidizing fluids typically have high frictional losses and can be corrosive to wellbore equipment. Advantageously, the acidizing fluid may comprise nanobubble formulations that are compatible with both mineral and organic acids. The combination of a mineral or organic acid with the mixed charges of the nanobubbles creates an acidizing fluid exhibiting a lower surface tension resulting in less frictional losses during pumping. The combination of a mineral or organic acid with the mixed charges of the nanobubbles further creates an acidizing fluid exhibiting a charge- shielding effect.

[0021] In some examples, positively charged nanobubbles are predominantly generated in an aqueous base fluid when the aqueous base fluid is maintained at a pH of 3 or less. In other examples, wherein the pH is nominally equal to or greater than 3, the surface of a nanobubble is negatively charged. Additionally, the point of zero charge (“PZC”) is equal to < 0 mV nominally at pH of 3. When the pH is at or near 3, the PZC is determined by the physicochemical properties of the nanobubble dispersion. The pH values of the nanobubble dispersion are greatly influenced by the ionic strength of the aqueous base fluid. The ionic strength of the aqueous base fluid is influenced by a number of different factors, including: the salinity and total dissolved solids, the type of gas, and the inclusion of any additive such as surfactants, organic molecules, or solvents. Additionally, the pH value of the aqueous base fluid can shift dynamically during preparation of the stimulation fluid by as much as + / -1 pH unit to as much as + / -2 pH units. In some examples, the pH value of the aqueous base fluid can shift by as much as + / -3 pH unit to as much as + / -4 pH units.

[0022] Positively charged nanobubbles, created when the pH of the aqueous base fluid is below a pH of 3 and where the point of zero charge (PZC) is zero, “shield” anionically charged additives and negatively charged nanobubbles shield cationically charged additives. Further, when the surface of a nanobubble is negatively charged, as when the pH of the aqueous base fluid is greater than 3, there is greater surface affinity for protons due to the negative zeta potential. This shielding reduces surface tension and may improve the reaction rate of the mineral or organic acid in a hydrocarbon producing zone. Additionally, the shielding may improve the miscibility of the acidizing fluid by preventing any additives from precipitating.

[0023] Another factor which influences the ionic strength of the aqueous base fluid is the zeta potential. The zeta potential can range from -10 to -50 mV when ultrapure water and certain gases (e.g., O2, N2, air, CO2, Xe, or combinations thereof) are used to prepare the nanobubble dispersion. In some examples, the zeta potential may range from -25 to -45 mV at a neutral pH as a function of ionic strength. In some examples, when surfactants are included within the stimulation fluid, the zeta potential can range from +45 to +60 mV.

[0024] The shielding may reduce corrosion of wellbore equipment by shielding oppositely charged protic ions within the acidizing fluid with nanobubbles such that the reactive surfaces of protic ions do not contact wellbore equipment. This reduces corrosion and reduces the reliance on additive corrosion inhibitors. Additionally, the nanobubbles improving the miscibility of the acidizing fluid lessens the reliance on surfactants by reducing the risk of additives precipitating out of solution.

[0025] The acidizing fluid generally comprises nanobubbles, a mineral or organic acid, and a liquid carrier. In some embodiments, the acidizing fluid may comprise nanobubbles, a mineral or organic acid, a liquid carrier, and an additive. The additive may be a salt or brine, corrosion inhibitor, corrosion inhibitor intensifier, biocide, scale control additive, clay control additive, gel stabilizer, anti-oxidant, polymer degradation prevention additive, relative permeability modifier, surfactant, demulsifier, foaming agent, wetting agent, dispersants, flocculants, scavenger (e.g., H2S scavengers, CO2 scavengers, or 02 scavengers), gelling agents, iron control agent, chelating agents, complexing agent, sequestering agent, metal ion control additive, or combinations thereof. A ‘surfactant’ in the context of acidizing fluids refers to classes of additives that can function as dispersants, emulsifiers, non-emulsifiers, surface tension reducers, hydrotropes, kosmotropes, chaotropes, capillary pressure lowering agents, wetting agents, foaming agents, demulsifying agents, or anti-sludging agents. Anionic dispersants are likely incompatible, whereas non-ionic dispersants are likely compatible in the acidizing fluid. In some examples, the acidizing fluid may be maintained at a pH of between 0-4.5 or at a pH of 5.5-8.5 , and preferably between pH 5 and 7.5.

[0026] The acidizing fluid may comprise a nanobubble dispersion in a liquid carrier. The nanobubble dispersion comprises a plurality of nanobubbles. Nanobubbles are bubbles having a mean diameter between about 50 nm to about 1000 nm. The nanobubbles are formed on the surface either at the wellsite or at an offsite location and then transported to the wellsite. After their formation, the nanobubbles may then be combined with the other components of the acidizing fluid. When the acidizing fluid is not needed, the acidizing fluid containing the nanobubbles may be stored or transported to another location for later use. The nanobubble dispersion may consist of nanobubbles having mixed positive and negative charges. In some examples, the nanobubble dispersion may consist of 0.1 % (v / v) negatively charged nanobubbles and 99.9% (v / v) positively charged nanobubbles. In some examples, the nanobubble dispersion may consist of 99.9 % (v / v) negatively charged nanobubbles and 0.1% (v / v) positively charged nanobubbles. The distribution of nanobubbles in the nanobubble dispersion may be affected by the pH of the stimulation fluid. The pH of the stimulation fluid may be adjusted by various additives present in the stimulation fluid.

[0027] The nanobubbles may be formed by any suitable manner. One mechanical method for forming the nanobubbles generally includes using a tube, in particular, a ceramic tube coated with a metallic oxide to inject nanobubbles into a liquid carrier. Through the wall of the tube, pores are machined or otherwise disposed in the tube wall and used to provide a channel from the interior of the tube to the exterior of the tube. It is preferable, but not required to use a tube having a constant pore size. The tube is placed within a container or vessel in which a liquid carrier (e.g., water) is flowed. The liquid carrier is flowed around the tube in a way to generate a turbulent flow of the liquid carrier, for example, the liquid carrier may be introduced into the vessel at an oblique or right angle relative to the tube. A gas is introduced into the lumen of the tube at a pressure greater than the fluid pressure in the vessel, thereby forcing the gas through the pores in the tube and into the liquid carrier flowing in the vessel. The pore size in the tube wall produces nanobubbles of the desired size as the gas is flowed through the pores into the liquid carrier.

[0028] Ceramic may be used as the tube material, but generally the tube can be produced from any rigid material adapted for maintaining a desired pore size when its lumen is filled with a pressurized gas. Maintaining a constant pore size can be beneficial for controlling the diameter range and mean diameter of the nanobubbles formed in the liquid carrier. As such, preferred materials for the tube are those having sufficient strength or wall thickness for maintaining a constant pore size when a pressurized gas is introduced into the lumen of the tube.

[0029] In a specific example, the tube is a single channel ceramic membrane coated with either metallic oxides, such as alumina, titania, zirconia, manganese, or combinations thereof, or carbonaceous materials such as carbon fiber, carbon nanotubes, carbon nanoparticles, or other non-metallic ceramics such as carbon nitride, carbon silicide, boron nitride, boron silicide, and known variations thereof. However, it is to be understood that the tube is not limited to any form or size of structure and can be in the form of monolith, multichannel tubes, etc. A singular mean pore size between about 50 nm to about 500 nm is used depending on the size of the bubble desired. Specific examples of metallic oxide coatings are AI2O3 or T1O2 crystalline coatings with a known mean pore size. The tube length, diameter, and size of the lumen can be any value sufficient for introduction of the gas into the liquid carrier.

[0030] In some examples, the liquid carrier may be an aqueous fluid. In other examples, an organic liquid may be used. The choice of the liquid carrier may be selected based on the other components of the acidizing fluid and the chosen wellbore operation. In some examples, the liquid carrier is free or substantially free of surfactants. The liquid carrier should be flowed around the tube in a turbulent manner to prevent the nanobubbles from coalescing into larger bubbles. The liquid carrier may be introduced into the vessel at an oblique or right angle relative to the tube in order to enhance the turbulence of the liquid carrier.

[0031] A selected gas is introduced into the tube under pressure from a gas source. The gas may be air, oxygen, hydrogen, nitrogen, carbon dioxide, argon, helium, waste flue gas, ammonia, chlorine, acidic gases with a vapor pressure that facilitates the generation of a hydronium species from a molecule bearing an -HX species where X is a halide, CH4, NG, flare gas, true gas, or combinations thereof. As the tube is closed (apart from its inlet), the gas can only exit through the pores of the tube. A pressure differential is maintained between the gas pressure inside the lumen of the tube and the liquid pressure outside the tube so that gas is forced through the pores of the tube. The gas emerges from the tube lumen as nanobubbles pulled into the turbulently flowing stream of the liquid carrier on the outside of the tube. The turbulent flow of the liquid carrier performs two functions. The liquid carrier removes the nanobubbles from the surface of the tube and carries away the nanobubbles as they form to prevent the nanobubbles from coalescing into large bubbles. The velocity of the liquid carrier may be any velocity sufficient for pulling the nanobubbles into the liquid carrier as the liquid carrier flows over the pores of the tube. The gas used to prepare the nanobubbles may be air, oxygen, hydrogen, nitrogen, carbon dioxide, argon, helium, waste flue gas, ammonia, chlorine, or combinations thereof; in some embodiments, other gases may be oxygen, carbon monoxide (CO), chlorine dioxide (002), bromine gas (Br2), fluorine gas (F2), chlorine monofluoride (C1F), ozone (03), nitrous oxide (N20), nitric oxide (NO), dinitrogen tetroxide (N2O4), nitrogen dioxide (N02), sulfur dioxide (S02), sulfur trioxide (S03). In preferred examples, the gas in the nanobubbles remains in a gaseous state at downhole conditions, such as a pressure in a range of from about 1000 to 3000 pounds per square inch (psi) and at a temperature of at least about 100° C. It some examples, it is preferable that the gas does not transition to a critical or supercritical state while downhole. This transition may negatively impact the stability of the nanobubble.

[0032] In some optional examples, the nanobubbles may be further configured to improve stability or add functionalization. For example, the nanobubble surface ionization (exterior surface charge) may be selected based upon the properties of the acidizing fluid and / or the hydrocarbon fluid within the subterranean formation. Surfactants or other types of surface modifiers may be added to the nanobubble dispersion (i.e. , the dispersed nanobubbles within the liquid carrier) and / or the acidizing fluid. Ionic surfactants, such as SDS (sodium dodecyl sulphate), CTAB (cetyltrimethylammonium bromide), and DTAB (dodecyl trimethylammonium bromide); non-ionic surfactants, such as the TWEEN™ series of detergents, e.g., TWEEN-20™ polyoxyethylene (20) sorbitan monolaurate, and TRITON X- 100™ (octylphenol ethoxylate); and / or zwitterionic surfactants, such as CBS (cocamidopropyl hydroxysultaine), may be introduced to the nanobubble dispersion and / or the acidizing fluid. Surface functionalization of the nanobubbles may be selected based upon the target subterranean formation of the wellbore and / or the properties of the hydrocarbon fluid within the subterranean formation. Surface functionalization may be performed through the use of surface modifiers configured to add functional groups such as -COOH, -OH, -C=O, -NHR2, - NH2R, -NR3, -[NR4]+, -OS(=O)2O-R, R-OP(=O)(OH)2, and salts thereof. Functionalization either through the addition of surfactants and / or other types of surface modifiers may be used to modify the exterior surface charge of the nanobubble to impart attraction or repulsion to other charged surfaces, such as water molecules, acidizing fluid additives, and / or other nanobubbles. In some examples, surface polarization may include common surface modifiers that either add dipoles or induce ionic polarization such as zwitterionic surfactants. In some examples, the nanobubble surfaces may be modified to repel other nanobubbles to prevent coalescence and increase the residence time and overall stability of the nanobubbles in the acidizing fluid. The use of surface modifiers is optional, and these materials may not be present in all examples.

[0033] The nanobubbles have a mean diameter in a range of between about 50 nm to about 1000 nm. For example, the nanobubbles may have a mean diameter ranging from about 50 nm to about 500 nm, about 75 nm to about 200 nm, or about 50 nm to about 150 nm. In some examples, the nanobubbles have a unimodal distribution of diameters. In some examples, the nanobubbles have a multimodal distribution of diameters.

[0034] The nanobubble dispersion described herein comprises a sufficiently concentrated volume of nanobubbles dispersed in the liquid carrier. In some examples, the nanobubbles have a population in the liquid carrier of between about 1 million to about 100 million nanobubbles per mL of liquid carrier. When the nanobubble dispersion is added to the acidizing fluid, the population of the nanobubbles in the acidizing fluid will vary based on the population of the nanobubbles in the dispersion and the volume of the nanobubble dispersion added to the acidizing fluid as a portion of the total volume of the acidizing fluid.

[0035] In some examples, the nanobubbles have a droplet resonance time of at least 24 days under ambient conditions at the surface. Conditions at wellsites may range from about 20° F to about 130° F. For example, the nanobubbles may have a droplet resonance time of at least 3 days, at least 5 days, at least 10 days, at least 15 days, at least 20 days, or at least 24 days.

[0036] To prepare the acidizing fluid, a volume of the nanobubble dispersion is combined with one or more of the other components of the acidizing fluid. The combining of the acidizing fluid components may occur in any order. The nanobubble dispersion is combined with one or more of the other components of the acidizing fluid at the surface, either at the wellsite or another location to then be transported to the wellsite. As the nanobubble dispersion is combined with the other components of the acidizing fluid, the nanobubbles within the dispersion will then disperse within the acidizing fluid.

[0037] The concentration of the nanobubble dispersion in the acidizing fluid may range from about 0.1% (w / v) to about 80% (w / v). The concentration may range from any lower limit to any upper limit and encompass any subset between the upper and lower limits. Some of the lower limits listed may be greater than some of the listed upper limits. One skilled in the art will recognize that the selected subset may require the selection of an upper limit in excess of the selected lower limit. Therefore, it is to be understood that every range of values is encompassed within the broader range of values. For example, the concentration of the nanobubble dispersion in the acidizing fluid may range from about 1% (w / v) to about 80% (w / v), from about 5% (w / v) to about 80% (w / v), from about 10% (w / v) to about 80% (w / v), from about 15% (w / v) to about 80% (w / v), from about 20% (w / v) to about 80% (w / v), from about 25% (w / v) to about 80% (w / v), from about 30% (w / v) to about 80% (w / v), from about 35% (w / v) to about 80% (w / v), from about 40% (w / v) to about 80% (w / v), from about 45% (w / v) to about 80% (w / v), from about 50% (w / v) to about 80% (w / v), from about 55% (w / v) to about 80% (w / v), from about 60% (w / v) to about 80% (w / v), from about 65% (w / v) to about 80% (w / v), from about 70% (w / v) to about 80% (w / v), or from about 75% (w / v) to about 80% (w / v). As another example, the concentration of the nanobubble dispersion in the acidizing fluid may range from about 1 % (w / v) to about 80% (w / v), from about 1 % (w / v) to about 75% (w / v), from about 1% (w / v) to about 70% (w / v), from about 1% (w / v) to about 65% (w / v), from about 1% (w / v) to about 60% (w / v), from about 1% (w / v) to about 55% (w / v), from about 1% (w / v) to about 50% (w / v), from about 1% (w / v) to about 45% (w / v), from about 1% (w / v) to about 40% (w / v), from about 1% (w / v) to about 35% (w / v), from about 1% (w / v) to about 30% (w / v), from about 1% (w / v) to about 25% (w / v), from about 1% (w / v) to about 20% (w / v), from about 1% (w / v) to about 15% (w / v), from about 1% (w / v) to about 10% (w / v), or from about 1% (w / v) to about 5% (w / v). With the benefit of this disclosure, one of ordinary skill in the art will be readily able to prepare an acidizing fluid having a desirable concentration of a nanobubble dispersion for use in a given wellbore operation.

[0038] The acidizing fluid described herein comprises an acid. In some examples, the acid may be an organic acid. In other examples, the acid may be a Bronsted Lowry acid. Organic acids may possess a lower reactivity than strong inorganic acids (such as HC1, HN03) and may be easier to inhibit, optionally requiring lower loadings of corrosion inhibitor. Preferred organic acids may include, but are not limited to, methanesulfonic acid, formic acid, acetic acid, monochloroacetic acid, oxalic acid, lactic acid, tartaric acid, maleic acid, glycolic acid, or any organic acid having a pKa constant equal to or lower than 4.5, and in some embodiments, having a pKa of 3.5. Preferred inorganic or mineral acids may include, but are not limited to, HC1, HI, HBr, H3PO4, HBr, HC1O, HCIO2, HCIO3, HCIO4, polyphosphoric acid, hydrofluoric acid (HF), HNO3 or combinations thereof. Hydrofluoric acid may be a suitable acid for some formations (e.g., a sandstone formation), or when there is use of siliceous or silicon-containing particulates. In some examples, hydrofluoric acid generating compounds may be used. Examples of hydrofluoric acid-generating compounds may include, but are not limited to, fluoroboric acid, fluorosulfuric acid, hexafluorophosphoric acid, hexafluoroantimonic acid, difluorophosphoric acid, hexafluorosilicic acid, potassium hydrogen difluoride, sodium hydrogen difluoride, polyvinylammonium fluoride, polyvinylpyridinium fluoride, pyridinium fluoride, imidazolium fluoride, ammonium fluoride, tetrafluoroborate salts, hexafluoroantimonate salts, hexafluorophosphate salts, bifluoride salts (e.g., ammonium bifluoride), perfluorinated organic compounds, boron trifluoride and various boron trifluoride complexes, derivatives thereof, and any combinations. Alternatively, another acid which may be used is a complexed form of a Bronsted acid, such as HC1 or H3PO4, with an aminoacid or an amide like urea, forming a urea-HCl or aminoacid-HCl acid and wherein the aminoacid can be lysine or taurine.

[0039] The acid hydrolyzes, or breaks down the chemical bonds, of oily hydrocarbons found on subterranean rock faces, creating smaller molecules. Specific examples of organic and mineral acids may include, but are not limited to, hydrochloric acid, hydrobromic acid, phosphoric acid, hydrofluoric acid, hypochlorous acid, chlorous acid, or formic acid, acetic acid, chloroacetic acid, dichloroacetic acid, trichloroacetic acid, methanesulfonic acid, citric acid, maleic acid, glycolic acid, lactic acid, malic acid, oxalic acid, gluconic acid, succinic acid, tartaric acid, sulfamic acid, lactic acid, thioglycolic acid, sulfamic acid trifluoroacetic acid, propionic acid, butanoic acid, pentanoic acid, hexanoic acid, heptanoic acid, octanoic acid, nonanoic acid, decanoic acid, dodecanoic acid, palmitic acid, stearic acid, sebacic acid, phthalic acid, isophthalic acid, terephthalic acid, adipic acid, pamoic acid, suberic acid, succinic acid, gluconic acid, traumatic acid, thapsic acid, valporic acid, hydroxypropionic acid, or any combinations of acids. Alternately, an acid precursor may be used which may form an acid in the wellbore. Example of the acid precursor may include, but are not limited to, esters of: acetic acid, citric acid, lactic acid, gluconic acid, glucaric acid, thioglycolic acid, glycolic acid, sulfamic acid formic acid, propionic acid, butanoic acid, pentanoic acid, hexanoic acid, heptanoic acid, octanoic acid, nonanoic acid, decanoic acid, dodecanoic acid, palmitic acid, stearic acid, sebacic acid, phthalic acid, isophthalic acid, terephthalic acid, adipic acid, pamoic acid, suberic acid, succinic acid, traumatic acid, thapsic acid, valporic acid, hydroxypropionic acid, or any combination of esters and / or acids. Preferred acid precursors may include, but are not limited to, esters, aliphatic polyesters, orthoesters, poly(orthoesters), poly(lactides), poly (glycolides), poly(e-caprolactones), poly(hydroxybutyrates), poly(anhydrides), ethylene glycol monoformate, ethylene glycol diformate, diethylene glycol diformate, glyceryl monoformate, glyceryl diformate, glyceryl triformate, triethylene glycol diformate, formate esters of pentaerythritol, the like, any derivative thereof, and any combinations. In some examples, derivatives of the above species may be used. The acid may be provided as a liquid or a solid depending on the species and handling constraints.

[0040] The concentration of the acid in the acidizing fluid may range from about 0.001% (w / v) to about 15% (w / v). The concentration may range from any lower limit to any upper limit and encompass any subset between the upper and lower limits. Some of the lower limits listed may be greater than some of the listed upper limits. One skilled in the art will recognize that the selected subset may require the selection of an upper limit in excess of the selected lower limit. Therefore, it is to be understood that every range of values is encompassed within the broader range of values. For example, the concentration of the acid in the acidizing fluid may range from about 0.001% (w / v) to about 15% (w / v), from about 0.005 (w / v) to about 15% (w / v), from about 0.01 (w / v) to about 15% (w / v), from about 0.05 (w / v) to about 15% (w / v), from about 0.1 % (w / v) to about 15% (w / v), from about 0.5% (w / v) to about 15% (w / v), from about

[0041] 1% (w / v) to about 15% (w / v), from about 2% (w / v) to about 15% (w / v), from about 3% (w / v) to about 15% (w / v), from about 4% (w / v) to about 15% (w / v), from about 5% (w / v) to about 15% (w / v), from about 6% (w / v) to about 15% (w / v), from about 7% (w / v) to about 15% (w / v), from about 8% (w / v) to about 15% (w / v), from about 9% (w / v) to about 15% (w / v), from about

[0042] 10% (w / v) to about 15% (w / v), from about 11% (w / v) to about 15% (w / v), from about 12%

[0043] (w / v) to about 15% (w / v), from about 13% (w / v) to about 15% (w / v), or from about 14% (w / v) to about 15% (w / v). As another example, the concentration of the acid in the acidizing fluid may range from about 0.001% (w / v) to about 15% (w / v), from about 0.001% (w / v) to about 14% (w / v), from about 0.001% (w / v) to about 13% (w / v), from about 0.001% (w / v) to about

[0044] 12% (w / v), from about 0.001% (w / v) to about 11% (w / v), from about 0.001% (w / v) to about

[0045] 10% (w / v), from about 0.001% (w / v) to about 9% (w / v), from about 0.001% (w / v) to about 8%

[0046] (w / v), from about 0.001% (w / v) to about 7% (w / v), from about 0.001% (w / v) to about 6%

[0047] (w / v), from about 0.001% (w / v) to about 5% (w / v), from about 0.001% (w / v) to about 4%

[0048] (w / v), from about 0.001% (w / v) to about 3% (w / v), from about 0.001% (w / v) to about 2%

[0049] (w / v), from about 0.001% (w / v) to about 1% (w / v), from about 0.001% (w / v) to about 0.5% (w / v), from about 0.001% (w / v) to about 0.1% (w / v), from about 0.001% (w / v) to about 0.05% (w / v), from about 0.001% (w / v) to about 0.01% (w / v), or from about 0.001% (w / v) to about 0.005% (w / v). With the benefit of this disclosure, one of ordinary skill in the art will be readily able to prepare and select an organic acid having a desirable concentration for a given application.

[0050] The acidizing fluid optionally comprises an additive. The additive may be a salt or brine, corrosion inhibitor, corrosion inhibitor intensifier, biocide, scale control additive, clay control additive, gel stabilizer, anti-oxidant, polymer degradation prevention additive, relative permeability modifier, surfactant, demulsifier, foaming agent, wetting agent, dispersant, flocculant, scavenger (e.g., H2S scavengers, CO2 scavengers, or O2 scavengers), gelling agent, iron control agent, chelating agent, complexing agent, sequestering agent, metal ion control additive, or combinations thereof.

[0051] Suitable corrosion inhibitors may include quaternary ammonium compounds and derivatives of this type of moiety, compounds having moieties selected from aldehyde, or ketone moieties, aromatic, heterocyclic, fused heterocyclic, or polyaromatics moieties, and macromolecules of having a molecular weight less than 120,000 grams per mole (g / mol). Corrosion inhibitors, in some embodiments, may be incompatible with the acidizing fluid or may not be useful. Specifically, a corrosion inhibitor for strong acids (e.g., HC1, HNO3, methanesulfonic acid, and chloroacetic acid) is not necessarily compatible or useful with weaker acids (e.g., H3PO4, formic acid, acetic acid, lactic acid, citric acid, gluconic acid, glycolic acid, urea hydrochloride complexes, and amino acid hydrochloride complexes referred to as retarded HC1 acids). The corrosion inhibitor may be selected from the group consisting of an acetylenic compound, cinnamaldehyde; dicinnamaldehyde; p-hydroxycinnamaldehyde; p-methylcinnamaldehyde; p-ethylcinnamaldehyde; p-methoxycinnamaldehyde; p- dimethylaminocinnamaldehyde; p-diethylaminocinnamaldehyde; p-nitrocinnamaldehyde; o- nitrocinnamaldehyde; o-allyloxycinnamaldehyde; 4-(3-propenal)cinnamaldehyde; p-sodium sulfocinnamaldehyde; p-trimethylammoniumcinnamaldehyde sulfate; p- trimethylammoniumcinnamaldehyde; o-methylsulfate; p-thiocyanocinnamaldehyde; p-(S- acetyl)thiocinnamaldehyde; p-(S-N,N-dimethylcarbamoylthio)cinnamaldehyde; p- chlorocinnamaldehyde; a-methylcinnamaldehyde; (P-methylcinnamaldehyde; a- chlorocinnamaldehyde; a-bromocinnamaldehyde; a-butylcinnamaldehyde; a- amylcinnamaldehyde; a-hexylcinnamaldehyde; a-bromo-p-cyanocinnamaldehyde; a-ethyl-p- methylcinnamaldehyde; p-methyl-a-pentylcinnamaldehyde; cinnamaloxime; cinnamonitrile; 5-phenyl-2,4-pentadienal; 7-phenyl-2,4,6-heptatrienal; aldehyde oligomers and mixtures thereof; where the carbon atom forms an imidazoline group, and one or more aldehyde oligomers being formed by the condensation reaction of, for instance benzaldehyde and acetaldehyde. The corrosion inhibitor can also be acetylenic alcohol selected from the group of 2-methyl-3-butyn-2-ol, 4-methyl-l-pentyn-3-ol, l-hexyn-3-ol, 4-ethyl-l-octyn-3-ol, propargyl alcohol, ethoxylated propargyl alcohol, propoxylated propargyl alcohol, benzylbutynol, 1- ethynylcyclohexanol, 5-decyne-4,7-diol, or combinations thereof.

[0052] The concentration of the corrosion inhibitor in the acidizing fluid may range from about 0.001% w / w to about 8% w / w. The concentration may range from any lower limit to any upper limit and encompass any subset between the upper and lower limits. Some of the lower limits listed may be greater than some of the listed upper limits. One skilled in the art will recognize that the selected subset may require the selection of an upper limit in excess of the selected lower limit. Therefore, it is to be understood that every range of values is encompassed within the broader range of values For example, the concentration of the acid in the acidizing fluid may range from about 0.001% (w / v) to about 8% (w / v), from about 0.005 (w / v) to about 8% (w / v), from about 0.01 (w / v) to about 8% (w / v), from about 0.05 (w / v) to about 8% (w / v), from about 0.1% (w / v) to about 8% (w / v), from about 0.5% (w / v) to about 8% (w / v), from about 1% (w / v) to about 8% (w / v), from about 2% (w / v) to about 8% (w / v), from about 3% (w / v) to about 8% (w / v), from about 4% (w / v) to about 8% (w / v), from about 5% (w / v) to about 8%

[0053] (w / v), from about 6% (w / v) to about 8% (w / v), or from about 7% (w / v) to about 8% (w / v). As another example, the concentration of the acid in the acidizing fluid may range from about

[0054] 0.001% (w / v) to about 8% (w / v), from about 0.001% (w / v) to about 7% (w / v), from about

[0055] 0.001% (w / v) to about 6% (w / v), from about 0.001% (w / v) to about 5% (w / v), from about

[0056] 0.001% (w / v) to about 4% (w / v), from about 0.001% (w / v) to about 3% (w / v), from about

[0057] 0.001% (w / v) to about 2% (w / v), from about 0.001% (w / v) to about 1% (w / v), from about

[0058] 0.001% (w / v) to about 0.5% (w / v), from about 0.001% (w / v) to about 0.1% (w / v), from about

[0059] 0.001% (w / v) to about 0.05% (w / v), from about 0.001% (w / v) to about 0.01% (w / v), or from about 0.001% (w / v) to about 0.005% (w / v).

[0060] Corrosion inhibitor intensifiers may be used in formations where the temperature exceeds the capability of corrosion inhibitors to prevent excessive and damaging corrosion to the wellbore tubing and equipment. Suitable corrosion inhibitor intensifiers may include group 15 metal sources selected from the group consisting of: antimony trioxide; antimony tetraoxide; antimony pentoxide; an antimony halide compound; antimony trichloride; antimony pentachloride; antimony trifluoride, antimony pentafluoride; antimony tartrate; antimony citrate; an alkali metal salt of antimony tartrate; antimony citrate; potassium pyroantimonate; an antimony adduct of ethylene glycol; a bismuth oxide compound; bismuth trioxide; bismuth tetraoxide; bismuth pentaoxide; a bismuth halide; bismuth trichloride; bismuth tribromide; bismuth triiodide; bismuth tartrate; bismuth citrate; an alkali metal salt of bismuth tartrate, an alkali metal salt of bismuth citrate; a bismuth oxyhalogen, or combinations thereof. Examples of compatible corrosion inhibitors include, but are not limited to, quaternary nitrogen containing compounds, aldehyde-containing compounds, and Mannich reaction products, thiazole, derivatives thereof, or combinations thereof.

[0061] The concentration of the corrosion inhibitor intensifier in the acidizing fluid may range from about 0.1% (w / v) to about 10% (w / v). The concentration may range from any lower limit to any upper limit and encompass any subset between the upper and lower limits. Some of the lower limits listed may be greater than some of the listed upper limits. One skilled in the art will recognize that the selected subset may require the selection of an upper limit in excess of the selected lower limit. Therefore, it is to be understood that every range of values is encompassed within the broader range of values. For example, the concentration of the corrosion inhibitor intensifier in the acidizing fluid may range from about 0.1% (w / v) to about 10% (w / v), from about 0.5% (w / v) to about 10% (w / v), from about 1% (w / v) to about 10% (w / v), from about 2% (w / v) to about 10% (w / v), from about 3% (w / v) to about 10% (w / v), from about 4% (w / v) to about 10% (w / v), from about 5% (w / v) to about 10% (w / v), from about 6% (w / v) to about 10% (w / v), from about 7% (w / v) to about 10% (w / v), from about 8% (w / v) to about 10% (w / v), or from about 9% (w / v) to about 10% (w / v). As another example, the concentration of the corrosion inhibitor intensifier in the acidizing fluid may range from about 0.1% (w / v) to about 10% (w / v), from about 0.1% (w / v) to about 9% (w / v), from about 0.1% (w / v) to about 8% (w / v), from about 0.1% (w / v) to about 7% (w / v), from about 0.1% (w / v) to about 6% (w / v), from about 0.1% (w / v) to about 5% (w / v), from about 0.1% (w / v) to about 4% (w / v), from about 0.1% (w / v) to about 3% (w / v), from about 0.1% (w / v) to about 2% (w / v), from about 0. 1 % (w / v) to about 1% (w / v), or from about 0.1% (w / v) to about 0.5% (w / v). With the benefit of this disclosure, one of ordinary skill in the art will be readily able to prepare and select corrosion inhibitor intensifier having a desirable concentration for a given application.

[0062] Surfactants or other types of surface modifiers may be added to the nanobubble dispersion (i.e., the dispersed nanobubbles within the liquid carrier) and / or the stimulation fluid. Ionic surfactants, such as SDS (sodium dodecyl sulphate), CTAB (cetyltrimethylammonium bromide), and DTAB (dodecyltrimethylammonium bromide); nonionic surfactants, such as the TWEEN™ series of detergents, e.g., TWEEN-20™ polyoxyethylene (20) sorbitan monolaurate, and TRITON X-100™ (octylphenol ethoxylate); and / or zwitterionic surfactants, such as CBS (cocamidopropyl hydroxysultaine), may be introduced to the nanobubble dispersion and / or the stimulation fluid.

[0063] The concentration of the surfactant or other type of surface modifier in the acidizing fluid may range from about 0.1% (w / v) to about 6% (w / v). The concentration may range from any lower limit to any upper limit and encompass any subset between the upper and lower limits. Some of the lower limits listed may be greater than some of the listed upper limits. One skilled in the art will recognize that the selected subset may require the selection of an upper limit in excess of the selected lower limit. Therefore, it is to be understood that every range of values is encompassed within the broader range of values. For example, the concentration of the surfactant or other type of surface modifier in the acidizing fluid may range from about 0.1% (w / v) to about 6% (w / v), from about 0.5% (w / v) to about 6% (w / v), from about 1% (w / v) to about 6% (w / v), from about 2% (w / v) to about 6% (w / v), from about 3% (w / v) to about 6% (w / v), from about 4% (w / v) to about 6% (w / v), or from about 5% (w / v) to about 6% (w / v). As another example, the concentration of the surfactant or other type of surface modifier in the acidizing fluid may range from about 0.01% (w / v) to about 6% (w / v), from about 0.01% (w / v) to about 5% (w / v), from about 0.01% (w / v) to about 4% (w / v), from about 0.01% (w / v) to about 3% (w / v), from about 0.01% (w / v) to about 2% (w / v), from about 0.01% (w / v) to about 1 % (w / v), from about 0.01 % (w / v) to about 0.5% (w / v), from about 0.01 % (w / v) to about 0.1 % (w / v), or from about 0.01% (w / v) to about 0.05% (w / v). With the benefit of this disclosure, one of ordinary skill in the art will be readily able to prepare and select a surfactant or other type of surface modifier having a desirable concentration for a given application.

[0064] Suitable polymeric based scale inhibitors may include polycarboxylate and sulfonated copolymers, polyacrylates and its sulfonated copolymers, and phophonate or phosphonic based scale inhibitors may include polyphosphonates, n-(phosphonomethyl) iminodiacetic acid (PMIDA), N-(carboxymethyl)-N-(phosphonomethyl)glycine, glycine, N,N'-1,2- ethanediylbis(N-(phosphonomethyl), glyphosine, aminotrimethylene phosphonic acid, sodium aminotris(methylenephosphonate), N-(2-hydroxyethyl)iminobis (methylphosphonic acid), phosphonic acid, P,P’-((2-propen-l-ylimino)bis(methylene))bis-, phosphonic acid, P,P',P"- (nitrilotris(methylene))tris-, (nitrilotris(methylene))trisphosphonic acid,

[0065] ((methylimino)-idimethylene)bisphosphonic acid, phosphonic acid, P,P',P",P"'-(oxybis(2,l- ethanediylnitrilobis->(methylene))tetrakis-, ((propylimino)bis(methylene))diphosphonic acid, phosphonic acid, P,P',P"-(nitrilotris(methylene))tris-, (ethylenedinitrilo) - tetramethylenephosphonic acid, ethylene->bis(nitrilodimethylene)tetraphosphonic acid, (ethylenebis(nitrilobis(methylene)))tetrakisphosphonic acid, tetrasodium tetrahydrogen (ethane- 1 ,2-diylbis(nitrilobis(methylene)))tetrakisphosphonate, 6-(bis(phosphonomethyl) amino)hexanoic acid, (phenylmethyl)imino)bis->(methylene)bisphosphonic acid, phosphonobutane tricarboxylic acid, 2-hydroxyphosphono dicarboxylic acid, any salts thereof, esters thereof, derivatives thereof, or combinations thereof.

[0066] The concentration of the polymeric scale inhibitor in the acidizing fluid may range from about 0.1% (w / v) to about 10% (w / v). The concentration may range from any lower limit to any upper limit and encompass any subset between the upper and lower limits. Some of the lower limits listed may be greater than some of the listed upper limits. One skilled in the art will recognize that the selected subset may require the selection of an upper limit in excess of the selected lower limit. Therefore, it is to be understood that every range of values is encompassed within the broader range of values. For example, the concentration of the polymeric scale inhibitor in the acidizing fluid may range from about 0.1% (w / v) to about 10% (w / v), from about 0.5% (w / v) to about 6% (w / v), from about 1% (w / v) to about 6% (w / v), from about 2% (w / v) to about 6% (w / v), from about 3% (w / v) to about 6% (w / v), from about 4% (w / v) to about 6% (w / v), or from about 5% (w / v) to about 6% (w / v). As another example, the concentration of the polymeric scale inhibitor in the acidizing fluid may range from about 0.01% (w / v) to about 6% (w / v), from about 0.01% (w / v) to about 5% (w / v), from about 0.01% (w / v) to about 4% (w / v), from about 0.01 % (w / v) to about 3% (w / v), from about 0.01 % (w / v) to about 2% (w / v), from about 0.01% (w / v) to about 1% (w / v), from about 0.01% (w / v) to about 0.5% (w / v), from about 0.01% (w / v) to about 0.1% (w / v), or from about 0.01% (w / v) to about 0.05% (w / v). With the benefit of this disclosure, one of ordinary skill in the art will be readily able to prepare and select a surfactant or other type of surface modifier having a desirable concentration for a given application.

[0067] Suitable cationic components are, but not limited to, arginine, lysine, polylysine, guanidine, ethoxylated amines, polyoxyalkylene amines, polyoxyethylene amines, polyoxypropylene amines, polyoxyalkylene cocamines, polyoxyethylene cocamines, polyoxypropylene cocamines, polyoxyalkylene tallow amines, polyoxyethylene tallow amines, polyoxypropylene tallow amines, polyoxy alkylene lauryl amines, polyoxyethylene lauryl amines, polyoxypropylene lauryl amines polyoxyalkylene amidoamines, polyoxypropylene amidoamine, polyether amines, polyether diamine, polyamino polyether, and the like, or combinations thereof. Cationic polymers or macromolecules may include most polyquatemiuon chemistriespolymers, poly(3-(trimethylaminium)-2-hydroxy-N,N-dimethyl- N-propylpran-l-aminium dichloride methacrylamide), poly(3-(trimethylaminium)-2-hydroxy- N,N-dimethyl-N-propylpran-l-aminium disulfate methacrylamide), N,N,N-trimethyl(oxiran- 2-yl)methanaminium, or combinations thereof.

[0068] The concentration of the cationic components in the acidizing fluid may range from about 0.1% (w / v) to about 6% (w / v). The concentration may range from any lower limit to any upper limit and encompass any subset between the upper and lower limits. Some of the lower limits listed may be greater than some of the listed upper limits. One skilled in the art will recognize that the selected subset may require the selection of an upper limit in excess of the selected lower limit. Therefore, it is to be understood that every range of values is encompassed within the broader range of values. For example, the concentration of the cationic components the acidizing fluid may range from about 0. 1% (w / v) to about 6% (w / v), from about 0.5% (w / v) to about 6% (w / v), from about 1% (w / v) to about 6% (w / v), from about 2% (w / v) to about 6% (w / v), from about 3% (w / v) to about 6% (w / v), from about 4% (w / v) to about 6% (w / v), or from about 5% (w / v) to about 6% (w / v). As another example, the concentration of the cationic components in the acidizing fluid may range from about 0.01% (w / v) to about 6% (w / v), from about 0.01% (w / v) to about 5% (w / v), from about 0.01% (w / v) to about 4% (w / v), from about

[0069] O.01% (w / v) to about 3% (w / v), from about 0.01% (w / v) to about 2% (w / v), from about 0.01% (w / v) to about 1% (w / v), from about 0.01% (w / v) to about 0.5% (w / v), from about 0.01% (w / v) to about 0.1% (w / v), or from about 0.01% (w / v) to about 0.05% (w / v). With the benefit of this disclosure, one of ordinary skill in the art will be readily able to prepare and select a cationic component having a desirable concentration for a given application.

[0070] Suitable scale control additives may include aminopolycarboxylic acids comprising a phosphonoalkyl moiety such as N-(phosphonomethyl) iminodiacetic acid (PMIDA, N- (carboxymethyl)-N-(phosphonomethyl)glycine, glycine, N,N'- 1 ,2-ethanediylbis(N-

[0071] (phosphonomethyl), glyphosine; aminotrimethylene phosphonic acid, sodium aminotris(methylenephosphonate), N-(2-hydroxyethyl)iminobis (methylphosphonic acid),

[0072] P,P'-((2-propen-l-ylimino)bis(methylene))bis-, phosphonic acid, P,P',P"-

[0073] (nitrilotris(methylene))tris-, (nitrilotris(methylene))trisphosphonic acid,

[0074] ((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,

[0075] (ethylenebis(nitrilobis(methylene)))tetrakisphosphonic acid, tetrasodium tetrahydrogen (ethane- 1 ,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-

[0076] [bis(phosphonomethyl)amino]ethyl]amino]methylphosphonic acid, pentamanganese; [bis [2- [bis(phosphonomethyl)aminojethyljaminojmethylphosphonic 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), sulfo- succinic acid, benzene sulfonic acid, naphthalene sulfonic acid, vinyl sulfonic acid, poly vinyl sulfonic acid, styrene sulfonic acid, polystyrene sulfonic acid, polyacrylic acid, the like, and any combination thereof.

[0077] The concentration of the scale control additive in the acidizing fluid may range from about 0.1% (w / v) to about 10% (w / v). The concentration may range from any lower limit to any upper limit and encompass any subset between the upper and lower limits. Some of the lower limits listed may be greater than some of the listed upper limits. One skilled in the art will recognize that the selected subset may require the selection of an upper limit in excess of the selected lower limit. Therefore, it is to be understood that every range of values is encompassed within the broader range of values. For example, the concentration of the scale control additive in the acidizing fluid may range from about 0.1% (w / v) to about 10% (w / v), from about 0.5% (w / v) to about 10% (w / v), from about 1% (w / v) to about 10% (w / v), from about 2% (w / v) to about 10% (w / v), from about 3% (w / v) to about 10% (w / v), from about 4% (w / v) to about 10% (w / v), from about 5% (w / v) to about 10% (w / v), from about 6% (w / v) to about 10% (w / v), from about 7% (w / v) to about 10% (w / v), from about 8% (w / v) to about 10% (w / v), or from about 9% (w / v) to about 10% (w / v). As another example, the concentration of the scale control additive in the acidizing fluid may range from about 0.1% (w / v) to about 10% (w / v), from about 0.1% (w / v) to about 9% (w / v), from about 0.1% (w / v) to about 8% (w / v), from about 0.1% (w / v) to about 7% (w / v), from about 0.1% (w / v) to about 6% (w / v), from about 0.1% (w / v) to about 5% (w / v), from about 0.1% (w / v) to about 4% (w / v), from about 0.1% (w / v) to about 3% (w / v), from about 0.1% (w / v) to about 2% (w / v), from about 0.1% (w / v) to about 1% (w / v), or from about 0.1% (w / v) to about 0.5% (w / v). With the benefit of this disclosure, one of ordinary skill in the art will be readily able to prepare and select a scale control additive having a desirable concentration for a given application.

[0078] Suitable metal ion control additives may include but are not limited to ethylenediaminetetraacetic acid (EDTA), hydroxyethylethylenediaminetriacetic acid (HEDTA), methylglycinediacetic acid (MGDA), tetrasodium glutamate diacetate (GLDA), nitrilotriacetic acid (NT A), trans- l,2-diaminocyclohexane-N,N,N’,N'-tetraacetic acid (CDTA); ethylenedioxybis(ethyliminodi(acetic acid)) (EGTA); diethylenetriaminepentaacetic acid (DTPA), hydroxyethyliminodiacetate (HE1DA), 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; polyhydroxy carboxylic acids such as citric acid, glycolic acid, lactic acid, maleic acid, gluconic acid, glucaric acid, tartaric acid, and monovalent salts thereof. The concentration of the metal ion control additive in the acidizing fluid may range from about 0.1% (w / v) to about 10% (w / v). The concentration may range from any lower limit to any upper limit and encompass any subset between the upper and lower limits. Some of the lower limits listed may be greater than some of the listed upper limits. One skilled in the art will recognize that the selected subset may require the selection of an upper limit in excess of the selected lower limit. Therefore, it is to be understood that every range of values is encompassed within the broader range of values. For example, the concentration of the metal ion control additive in the acidizing fluid may range from about 0.1 % (w / v) to about 10% (w / v), from about 0.5% (w / v) to about 10% (w / v), from about 1% (w / v) to about 10% (w / v), from about 2% (w / v) to about 10% (w / v), from about 3% (w / v) to about 10% (w / v), from about 4% (w / v) to about 10% (w / v), from about 5% (w / v) to about 10% (w / v), from about 6% (w / v) to about 10% (w / v), from about 7% (w / v) to about 10% (w / v), from about 8% (w / v) to about 10% (w / v), or from about 9% (w / v) to about 10% (w / v). As another example, the concentration of the metal ion control additives in the acidizing fluid may range from about 0.01% (w / v) to about 10% (w / v), from about 0.01% (w / v) to about 9% (w / v), from about 0.01% (w / v) to about 8% (w / v), from about 0.01% (w / v) to about 7% (w / v), from about 0.01% (w / v) to about 6% (w / v), from about 0.01% (w / v) to about 5% (w / v), from about 0.01% (w / v) to about 4% (w / v), from about 0.01% (w / v) to about 3% (w / v), from about 0.01% (w / v) to about 2% (w / v), from about 0.01% (w / v) to about 1% (w / v), from about 0.01% (w / v) to about 0.5% (w / v), from about 0.01% (w / v) to about 0.1% (w / v), or from about 0.01% (w / v) to about0.05% (w / v). With the benefit of this disclosure, one of ordinary skill in the art will be readily able to prepare and select a metal ion control additive having a desirable concentration for a given application.

[0079] Suitable clay control additives may include polyamine, polyquaternary ammonium, polyacrylamide, cationic surfactants, or combinations thereof.

[0080] The concentration of the clay control additive in the acidizing fluid may range from about 0.1% (w / v) to about 5% (w / v). The concentration may range from any lower limit to any upper limit and encompass any subset between the upper and lower limits. Some of the lower limits listed may be greater than some of the listed upper limits. One skilled in the art will recognize that the selected subset may require the selection of an upper limit in excess of the selected lower limit. Therefore, it is to be understood that every range of values is encompassed within the broader range of values. For example, the concentration of the clay control additive in the acidizing fluid may range from about 0.1% (w / v) to about 5% (w / v), from about 0.5% (w / v) to about 5% (w / v), from about 1% (w / v) to about 5% (w / v), from about 2% (w / v) to about 5% (w / v), from about 3% (w / v) to about 5% (w / v), or from about 4% (w / v) to about 5%. As another example, the concentration of the clay control additive in the acidizing fluid may range from about from about 0.01% (w / v) to about 5% (w / v), from about 0.01% (w / v) to about 4% (w / v), from about 0.01% (w / v) to about 3% (w / v), from about 0.01% (w / v) to about 2% (w / v), from about 0.01% (w / v) to about 1% (w / v), from about 0.01% (w / v) to about 0.5% (w / v), from about 0.01% (w / v) to about 0.1% (w / v), or from about 0.01% (w / v) to about 0.05% (w / v). With the benefit of this disclosure, one of ordinary skill in the art will be readily able to prepare and select a clay control additive having a desirable concentration for a given application.

[0081] Suitable polymers may include viscoelastic surfactants and corrosion inhibitor blends which may have charge dependent incompatibility and are composed of different heteroatomic molecules that are primarily organic (hydrophobic or minimally water-miscible) with varied molecular weight typically less than 5,000 g / mole.

[0082] The concentration of the polymer in the acidizing fluid may range from about 0.1% (w / v) to about 5% (w / v). The concentration may range from any lower limit to any upper limit and encompass any subset between the upper and lower limits. Some of the lower limits listed may be greater than some of the listed upper limits. One skilled in the art will recognize that the selected subset may require the selection of an upper limit in excess of the selected lower limit. Therefore, it is to be understood that every range of values is encompassed within the broader range of values. For example, the concentration of the polymer in the acidizing fluid may range from about 0.1% (w / v) to about 5% (w / v), from about 0.5% (w / v) to about 5% (w / v), from about 1% (w / v) to about 5% (w / v), from about 2% (w / v) to about 5% (w / v), from about 3% (w / v) to about 5% (w / v), or from about 4% (w / v) to about 5%. As another example, the concentration of the polymer in the acidizing fluid may range from about from about 0.01% (w / v) to about 5% (w / v), from about 0.01% (w / v) to about 4% (w / v), from about 0.01% (w / v) to about 3% (w / v), from about 0.01% (w / v) to about 2% (w / v), from about 0.01% (w / v) to about 1% (w / v), from about 0.01% (w / v) to about 0.5% (w / v), from about 0.01% (w / v) to about 0.1% (w / v), or from about 0.01% (w / v) to about 0.05% (w / v). With the benefit of this disclosure, one of ordinary skill in the art will be readily able to prepare and select a polymer having a desirable concentration for a given application.

[0083] The acidizing fluid described herein comprises an aqueous base fluid, for example, freshwater, saltwater (e.g., water containing one or more salts dissolved therein), brine (e.g., saturated saltwater, including saturated saltwater produced from subterranean formations), seawater, produced water, recycled water, reclaimed water, municipal wastewater or any combination thereof. Generally, the aqueous base fluid may be from any source provided that the aqueous base fluid does not contain an excess of compounds that may undesirably affect other components in the acidizing fluid. In the case of brines, the aqueous base fluid may comprise a monovalent brine or a divalent brine. Suitable monovalent brines may include, for example, sodium chloride brines, sodium bromide brines, potassium chloride brines, potassium bromide brines, and the like. Suitable divalent brines can include, for example, magnesium chloride brines, calcium chloride brines, calcium bromide brines, zinc bromide brines, and the like. One of ordinary skill in the art, with the benefit of this disclosure, should be readily able to select an aqueous base fluid for a chosen application.

[0084] Suitable brines can be a monovalent brine or a divalent brine. Suitable monovalent brines may include, for example, sodium chloride brines, sodium bromide brines, potassium chloride brines, potassium bromide brines, and the like. Suitable divalent brines can include, for example, magnesium chloride brines, calcium chloride brines, calcium bromide brines, zinc bromide brines, and the like.

[0085] The concentration of the aqueous base fluid in the acidizing fluid may range from about 1% (w / v) to about 99% (w / v). The concentration of the aqueous base fluid in the acidizing fluid may range from any lower limit to any upper limit and encompass any subset between the upper and lower limits. Some of the lower limits listed may be greater than some of the listed upper limits. One skilled in the art will recognize that the selected subset may require the selection of an upper limit in excess of the selected lower limit. Therefore, it is to be understood that every range of values is encompassed within the broader range of values. For example, the concentration of the aqueous base fluid in the acidizing fluid may range from about 1 % (w / v) to about 99% (w / v), from about 5% (w / v) to about 99% (w / v), from about 10% (w / v) to about 99% (w / v), from about 15% (w / v) to about 99% (w / v), from about 20% (w / v) to about 99% (w / v), from about 25% (w / v) to about 99% (w / v), from about 30% (w / v) to about 99% (w / v), from about 35% (w / v) to about 99% (w / v), from about 40% (w / v) to about 99% (w / v), from about 45% (w / v) to about 99% (w / v), from about 55% (w / v) to about 99% (w / v), from about 60% (w / v) to about 99% (w / v), from about 65% (w / v) to about 99% (w / v), from about 70% (w / v) to about 99% (w / v), from about 75% (w / v) to about 99% (w / v), from about 80% (w / v) to about 99% (w / v), from about 85% (w / v) to about 99% (w / v), from about 90% (w / v) to about 99% (w / v), or from about 95% (w / v) to about 99% (w / v). As another example, the concentration of the aqueous base fluid in the acidizing fluid may range from about 1% (w / v) to about 99% (w / v), from about 1% (w / v) to about 95% (w / v), from about 1% (w / v) to about 90% (w / v), from about 1% (w / v) to about 85% (w / v), from about 1% (w / v) to about 80% (w / v), from about 1% (w / v) to about 75% (w / v), from about 1% (w / v) to about 70% (w / v), from about 1% (w / v) to about 65% (w / v), from about 1% (w / v) to about 60% (w / v), from about 1% (w / v) to about 55% (w / v), from about 1% (w / v) to about 50% (w / v), from about 1% (w / v) to about 45% (w / v), from about 1% (w / v) to about 40% (w / v), from about 1% (w / v) to about 35% (w / v), from about 1% (w / v) to about 30% (w / v), from about 1% (w / v) to about 25% (w / v), from about 1% (w / v) to about 20% (w / v), from about 1% (w / v) to about 15% (w / v), from about 1% (w / v) to about 10% (w / v), or from about 1% (w / v) to about 5% (w / v). With the benefit of this disclosure, one of ordinary skill in the art will be able to prepare an acidizing fluid having a sufficient concentration of an aqueous base fluid for a given application.

[0086] FIG. 1 illustrates a schematic of the surface and near-surface portions of a system 100 that delivers the acidizing fluid described herein to a downhole location, according to one or more examples. It should be noted that while FIG. 1 generally depicts a land-based system, it is to be recognized that system 100 may be operated in subsea locations as well. As depicted in FIG. 1, system 100 includes a mixing tank 105, in which an acidizing fluid is formulated. The acidizing fluid may be conveyed to a pump 140 which elevates the acidizing fluid to a desired pressure to drive the acidizing fluid to wellhead 115 via line 110, where the acidizing fluid enters wellbore conduit 120. Conduit 120 extends from wellhead 115 into a wellbore 125 penetrating subterranean formation 130. Wellhead 115 is illustrated as comprising a derrick, but it is to be understood that other wellhead 115 arrangements such as a Christmas tree may be used in some examples. Wellbore 125 may be any type of wellbore including vertical, horizontal, deviated, etc. The illustrated portion of wellbore 125 is cased with a casing 135. In some alternative examples, wellbore 125 may be uncased. Upon being ejected from conduit 120, the acidizing fluid may subsequently enter into subterranean formation 130 as described in FIG. 2 below. Pump 140 is configured to raise the fluid pressure of the acidizing fluid to a desired pressure before its introduction into conduit 120. The acidizing fluid may be introduced into the wellbore 125 to increase the permeability of the subterranean formation 130 before production in an acid spearhead, during fracturing, or after initial fracturing has concluded. The acidizing fluid may be introduced into the wellbore 125 during or after drilling of the wellbore 125. The acidizing fluid may be introduced into the wellbore 125 during or after fracturing of the wellbore 125. The acidizing fluid may be introduced into the wellbore during or after performing an enhanced oil recovery operation in the wellbore 125. The acidizing fluid may be introduced into the wellbore 125 during or after performing a completion operation in the wellbore 125, such as cementing a portion of the wellbore. The acidizing fluid may be introduced into the wellbore 125 during or after a different wellbore treatment operation, such as treating the wellbore 125 with a fluid pill (e.g., a fluid loss control pill), an acidizing operation, etc. FIG. 2 illustrates a schematic of the downhole portion of the system 100 illustrated in FIG. 1, according to one or more examples. In the example of FIG. 2, the acidizing fluid is introduced into the wellbore 125 after a fracturing fluid has been used to form one or more fractures in the subterranean formation 130. Optionally, the acidizing fluid may be introduced as the fracturing fluid. As depicted in FIG. 2, conduit 120 extends from the wellhead 115 (as illustrated in FIG. 1) into wellbore 125 penetrating subterranean formation 130. After descending through the heel 145 of the wellbore 125, the conduit 120 is coupled to one or more packers 150 positioned to isolate an interval of wellbore 125. An acidizing fluid 155, as described herein, may exit tubular 120 through openings 160. The acidizing fluid 155 may be introduced into the subterranean formation 130 via a primary fracture 165 of other such opening into the subterranean formation 130. The acidizing fluid 155 may contact the subterranean formation 130 to clean an oily rock face within the subterranean formation 130. The acidizing fluid 155 and the hydrocarbon carbon fluid may be flowed out of the wellbore 125.

[0087] It is to be recognized that system 100 is merely exemplary in nature, and various additional components may be present that have not necessarily been depicted in FIGS. 1 and 2 in the interest of clarity. Non-limiting additional components that may be present include, but are not limited to, supply hoppers, valves, condensers, adapters, joints, gauges, sensors, compressors, pressure controllers, pressure sensors, flow rate controllers, flow rate sensors, temperature sensors, and the like.

[0088] It should be clearly understood that the examples illustrated by FIGS. 1 and 2 are merely general applications of the principles of this disclosure in practice, and a wide variety of other examples are possible. Therefore, the scope of this disclosure is not limited in any manner to the details of FIGS. 1 and 2 as described herein.

[0089] FIG. 3 is a schematic showing one example of a system 200 for an injection well 205. Some portions of the injection well 205 are illustrated as uncased; however, it is to be understood that the injection well 205 may have portions that are cased or uncased as desired. An acidizing fluid 230 may be introduced into the wellbore 220 via the Christmas tree 235, or any other sufficient injection point into the wellbore 220. Although system 200 depicts a Christmas tree 235 at the wellhead, other wellhead arrangements may be used for the wellbore operation. In the illustrated example, the acidizing fluid 230 is introduced into conduit 240 to the bottom of the wellbore 220 and up through the annulus 245 where it may contact the target formation interval 210. The acidizing fluid 230 flows into the adjacent subterranean formation of the formation interval 210 to contact any hydrocarbon fluids within. The acidizing fluid 230 is not flowed back but may enter into the subterranean formation 225 at the targeted formation interval 210. The acidizing fluid 230 drives the hydrocarbon fluids into a nearby producing well also penetrating subterranean formation 225.

[0090] It should be clearly understood that the system 200 illustrated by FIG. 3 is merely a general application of the principles of this disclosure in practice, and a wide variety of other examples are possible. Therefore, the scope of this disclosure is not limited in any manner to the details of FIG. 3 as described herein. Other subterranean formations where this disclosure has applicability include a water production well, an injection well, a monitoring well, or a geothermal well, a storage wells where the permanent or temporary entrapment of industrial emissions containing gases such as carbon dioxide (CO2), methane and volatile organic hydrocarbons primarily, but also other others gases such as nitrogen oxides (NOx) or sulfur oxides (SOx); or halogenated gases such as fluorocarbons, oxygenenated fluorocarbons, or chlorocarbons, or other organo-halogenated small molecules (Cl to C5).

[0091] FIG. 4 is an example of the charge-shielding effect of the nanobubbles 310 on protic molecules 300 within an acidizing fluid. Without the use of nanobubbles 310, protic molecules 300 in solution may contact wellbore machinery causing corrosion. When charged protic ions 301, 302 with opposite charges are contained within the same solution, nanobubbles 310 provide a “charge-shielding” effect for the cationic and anionic components, i.e., the charged protic ions 301, 302, within the acidizing fluid mitigate the effects of corrosion by reducing the contact of the charged protic ions 301, 302 with wellbore equipment. The nanobubbles 310 may be a mixture of positively charged nanobubbles 303 and negatively charged nanobubbles 304, which shield oppositely charged protic ions 301, 302. In detail, negatively charged nanobubbles 304 will shield positively, or cationically, charged protic ions 302. Positively charged nanobubbles 303 will shield negatively, or anionically, charged protic ions 301.

[0092] The acidizing fluids disclosed herein may directly or indirectly affect one or more components or pieces of equipment associated with or which may come into contact with the acidizing fluid s such as, but not limited to, wellbore casing, wellbore liner, completion string, insert strings, drill string, coiled tubing, slickline, wireline, drill pipe, drill collars, mud motors, downhole motors and / or pumps, cement pumps, surface-mounted motors and / or pumps, centralizers, turbolizers, scratchers, floats (e.g., shoes, collars, valves, etc.), logging tools and related telemetry equipment, actuators (e.g., electromechanical devices, hydromechanical devices, etc.), sliding sleeves, production sleeves, plugs, screens, filters, flow control devices (e.g., inflow control devices, autonomous inflow control devices, outflow control devices, etc.), couplings (e.g., electro-hydraulic wet connect, dry connect, inductive coupler, etc.), control lines (e.g., electrical, fiber optic, hydraulic, etc.), surveillance lines, drill bits and reamers, sensors or distributed sensors, downhole heat exchangers, valves and corresponding actuation devices, tool seals, packers, cement plugs, bridge plugs, and other wellbore isolation devices, or components, and the like.

[0093] Provided are acidizing fluids for treating a wellbore in accordance with the disclosure and the illustrated FIGs. An example acidizing fluid comprises: an aqueous base fluid, an acid, and a nanobubble dispersion, wherein the nanobubble dispersion comprises a mixture of positively charged nanobubbles and negatively charged nanobubbles.

[0094] Additionally or alternatively, the acidizing fluid may include one or more of the following features individually or in combination. The nanobubbles within the nanobubble dispersion may comprise a mean diameter between about 50 nm to about 1000 nm. The nanobubble dispersion may be present in the acidizing fluid in a concentration of about 0.1% (w / v) to about 80% (w / v). The nanobubbles within the nanobubble dispersion may envelop a gas selected from the group consisting of air, oxygen, carbon dioxide, nitrogen, hydrogen, argon, waste flue gas, ammonia, chlorine, acidic gases with a vapor pressure that facilitates the generation of a hydronium species from a molecule bearing an -HX species where X is a halide, CH4, NG, flare gas, true gas, or any combination thereof. The acidizing fluid may further comprise an additive. The additive may be selected from the group consisting of a corrosion inhibitor, biocide, scale control additive, clay control additive, polymer, and a surfactant. The acid may be present in the acidizing fluid in a concentration of about 0.001% (w / v) to about 15% (w / v). The additive may be present in the acidizing fluid in a concentration of about 0.001% (w / v) to about 10% (w / v). The acidizing fluid pH may range from about 0 to about 4.5. The acidizing fluid pH may range from about 5.5 to about 7.5. The nanobubbles within the nanobubble dispersion may have a population size of about 1 million to about 100 million per mL of the acidizing fluid.

[0095] Provided are methods for treating a wellbore with an acidizing fluid in accordance with the disclosure and the illustrated FIGs. An example method comprises: introducing the acidizing fluid into a wellbore penetrating the subterranean formation, and contacting a rock surface in the subterranean formation with the acidizing fluid, wherein the nanobubble dispersion comprises a mixture of positively charged nanobubbles and negatively charged nanobubbles.

[0096] Additionally or alternatively, the method may include one or more of the following features individually or in combination. The nanobubbles within the nanobubble dispersion may comprise a mean diameter between about 50 nm to about 1000 nm. The nanobubble dispersion may be present in the acidizing fluid in a concentration of about 0.1% (w / v) to about 80% (w / v). The nanobubbles within the nanobubble dispersion may envelop a gas selected from the group consisting of air, oxygen, carbon dioxide, nitrogen, hydrogen, argon, waste flue gas, ammonia, chlorine, acidic gases with a vapor pressure that facilitates the generation of a hydronium species from a molecule bearing an -HX species where X is a halide, CH4, NG, flare gas, true gas, or any combination thereof. The acidizing fluid may further comprise an additive. The additive may be selected from the group consisting of a corrosion inhibitor, biocide, scale control additive, clay control additive, polymer, and a surfactant. The acid may be present in the acidizing fluid in a concentration of about 0.001 % (w / v) to about 15% (w / v). The additive may be present in the acidizing fluid in a concentration of about 0.001% (w / v) to about 10% (w / v). The acidizing fluid pH may range from about 0 to about 4.5. The acidizing fluid pH may range from about 5.5 to about 7.5. The nanobubbles within the nanobubble dispersion may have a population size of about 1 million to about 100 million per mL of the acidizing fluid.

[0097] Provided are systems for treating a wellbore with an acidizing fluid in accordance with the disclosure and the illustrated FIGs. An example system comprises: the acidizing fluid, and mixing equipment configured to mix the aqueous base fluid, the acid, and the nanobubble dispersion; and pumping equipment configured to pump the acidizing fluid in the wellbore, wherein the nanobubbles within the nanobubble dispersion comprise a mixture of positively charged nanobubbles and negatively charged nanobubbles.

[0098] Additionally or alternatively, the system may include one or more of the following features individually or in combination. The nanobubbles within the nanobubble dispersion may comprise a mean diameter between about 50 nm to about 1000 nm. The nanobubble dispersion may be present in the acidizing fluid in a concentration of about 0.1% (w / v) to about 80% (w / v). The nanobubbles within the nanobubble dispersion may envelop a gas selected from the group consisting of air, oxygen, carbon dioxide, nitrogen, hydrogen, argon, waste flue gas, ammonia, chlorine, acidic gases with a vapor pressure that facilitates the generation of a hydronium species from a molecule bearing an -HX species where X is a halide, CH4, NG, flare gas, true gas, or any combination thereof. The acidizing fluid may further comprise an additive. The additive may be selected from the group consisting of a corrosion inhibitor, biocide, scale control additive, clay control additive, polymer, and a surfactant. The acid may be present in the acidizing fluid in a concentration of about 0.001% (w / v) to about 15% (w / v). The additive may be present in the acidizing fluid in a concentration of about 0.001% (w / v) to about 10% (w / v). The acidizing fluid pH may range from about 0 to about 4.5. The acidizing fluid pH may range from about 5.5 to about 7.5. The nanobubbles within the nanobubble dispersion may have a population size of about 1 million to about 100 million per mL of the acidizing fluid.

[0099] The preceding description provides various examples of the systems and methods of use disclosed herein which may contain different method steps and alternative combinations of components. It should be understood that, although individual examples may be discussed herein, the present disclosure covers all combinations of the disclosed examples, including, without limitation, the different component combinations, method step combinations, and properties of the system. It should be understood that the compositions and methods are described in terms of “comprising,” “containing,” or “including” various components or steps. The systems and methods can also “consist essentially of or “consist of the various components and steps. 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.

[0100] For the sake of brevity, only certain ranges are explicitly disclosed herein. However, ranges from any lower limit may be combined with any upper limit to recite a range not explicitly recited, as well as ranges from any lower limit may be combined with any other lower limit to recite a range not explicitly recited. In the same way, ranges from any upper limit may be combined with any other upper limit to recite a range not explicitly recited. Additionally, whenever a numerical range with a lower limit and an upper limit is disclosed, any number and any included range falling within the range are 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 even if not explicitly recited. Thus, every point or individual value may serve as its own lower or upper limit combined with any other point or individual value or any other lower or upper limit, to recite a range not explicitly recited.

[0101] One or more illustrative examples incorporating the examples disclosed herein are presented. Not all features of a physical implementation are described or shown in this application for the sake of clarity. Therefore, the disclosed systems and methods are well adapted to attain the ends and advantages mentioned, as well as those that are inherent therein. The particular examples disclosed above are illustrative only, as the teachings of the present disclosure 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 examples disclosed above may be altered, combined, or modified, and all such variations are considered within the scope of the present disclosure. The systems and methods illustratively disclosed herein may suitably be practiced in the absence of any element that is not specifically disclosed herein and / or any optional element disclosed herein. Although the present disclosure and its advantages have been described in detail, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the disclosure as defined by the following claims.

Claims

WHAT IS CLAIMED IS:

1. An acidizing fluid for a wellbore, the acidizing fluid comprises: an aqueous base fluid, an acid, and a nanobubble dispersion comprising a plurality of nanobubbles, wherein the nanobubble dispersion comprises a mixture of positively charged nanobubbles and negatively charged nanobubbles.

2. The acidizing fluid of claim 1, wherein the nanobubbles within the nanobubble dispersion comprise a mean diameter between about 50 nm to about 1000 nm.

3. The acidizing fluid of claim 1, wherein the nanobubble dispersion is present in the acidizing fluid in a concentration of about 0.1% (w / v) to about 80% (w / v).

4. The acidizing fluid of claim 1, wherein the nanobubbles within the nanobubble dispersion envelop a gas selected from the group consisting of air, oxygen, carbon dioxide, nitrogen, hydrogen, argon, waste flue gas, ammonia, chlorine, acidic gases with a vapor pressure that facilitates the generation of a hydronium species from a molecule bearing an -HX species where X is a halide, CH4, NG, flare gas, true gas, or any combination thereof.

5. The acidizing fluid of claim 1, further comprising an additive.

6. The acidizing fluid of claim 5, wherein the additive is selected from the group consisting of a corrosion inhibitor, biocide, scale control additive, clay control additive, polymer, and a surfactant.

7. The acidizing fluid of claim 1, wherein the acid is present in the acidizing fluid in a concentration of about 0.001% (w / v) to about 15% (w / v).

8. The acidizing fluid of claim 5, wherein the additive is present in the acidizing fluid in a concentration of about 0.001% (w / v) to about 10% (w / v).

9. The acidizing fluid of claim 1, wherein the pH ranges from about 0 to about 4.5.

10. The acidizing fluid of claim 1, wherein the pH ranges from about 5.5 to about 7.5.

11. A method for treating a subterranean formation, the method comprises: introducing an acidizing fluid into a wellbore penetrating the subterranean formation, the acidizing fluid comprising: an aqueous base fluid, an acid, and a nanobubble dispersion comprising a plurality of nanobubbles, and contacting a rock surface in the subterranean formation with the acidizing fluid, wherein the nanobubble dispersion comprises a mixture of positively charged nanobubbles and negatively charged nanobubbles.

12. The method of claim 11, wherein the nanobubbles within the nanobubble dispersion comprise a mean diameter between about 50 nm to about 1000 nm.

13. The method of claim 11, wherein the acid is present in the acidizing fluid in a concentration of about 0.001% (w / v) to about 15% (w / v).

14. The method of claim 11, further comprising an additive.

15. The method of claim 14, wherein the additive is selected from the group consisting of a corrosion inhibitor, biocide, scale control additive, clay control additive, polymer, and a surfactant.

16. The method of claim 15, wherein the additive is present in the acidizing fluid in a concentration of about 0.001% (w / v) to about 10% (w / v).

17. The method of claim 11, wherein the nanobubbles within the nanobubble dispersion envelop a gas selected from the group consisting of air, oxygen, carbon dioxide, nitrogen, hydrogen, argon, waste flue gas, ammonia, chlorine, acidic gases with a vapor pressure that facilitates the generation of a hydronium species from a molecule bearing an -HX species where X is a halide, CH4, NG, flare gas, true gas, or any combination thereof.

18. A system for drilling a wellbore, the system comprises: an acidizing fluid comprising: an aqueous base fluid, an acid, and a nanobubble dispersion comprising a plurality of nanobubbles, and mixing equipment configured to mix the aqueous base fluid, the acid, and the nanobubble dispersion; and pumping equipment configured to pump the acidizing fluid in the wellbore, wherein the nanobubbles within the nanobubble dispersion comprise a mixture of positively charged nanobubbles and negatively charged nanobubbles.

19. The system of claim 17, wherein the nanobubbles within the nanobubble dispersion comprise a mean diameter between about 50 nm to about 1000 nm.

20. The system of claim 17, wherein the nanobubbles within the nanobubble dispersion have a population size of about 1 million to about 100 million per mL of the acidizing fluid.

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