Treatment fluid for scale control

Abstract

The present disclosure relates to methods and compositions for controlling the formation of scale in hydrocarbon extraction and / or geothermal applications. The anti-scaling composition that inhibits the formation of scale in oil fields and / or geoengineering applications consists essentially of: a polymer that is the reaction product of (i) an acrylate monomer and (ii) 2-acrylamido-2-methyl-1-propanesulfonicacid (AMPS) and / or monomethyl maleate (MMM); and methylglycine N, N- diacetic acid and / or salts thereof.

Description

PATENT APPLICATION Attorney Docket No.: 364.1528PC TREATMENT FLUID FOR SCALE CONTROL CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to U.S. Application No.63 / 587,115, filed September 30th, 2023, the disclosure of which is incorporated by reference in their entirety. TECHNICAL FIELD OF THE INVENTION

[0001] The present invention generally relates to controlling the formation of scale in water systems. More particularly, the present invention relates to methods and compositions for inhibiting the formation of scale in systems that use aqueous-based fluids in well drilling, heat, hydrocarbon extraction, or other well operations in subterranean formations. BACKGROUND OF THE INVENTION

[0002] This section provides background information related to the present disclosure which is not necessarily prior art.

[0003] Formation water or produced water are waters trapped in underground formations that are brought to the surface during oil and gas exploration and production. In coal bed methane production, wells are drilled into coal seams, and the water located there is pumped to the surface to allow gas to be released from the coal seams. It may include water from the reservoir, water injected into the formation, and any chemicals added during the drilling, production, and treatment processes. As the water has been in contact with the hydrocarbon-bearing formation at elevated temperatures, it has some of the chemical characteristics of the formation and the hydrocarbon itself. The physical and chemical properties of produced water vary considerably depending on the geographic location of the field, the geological formation from which it comes, and the type of hydrocarbon product being produced. Produced water properties and volume can even vary throughout the lifetime of a reservoir.

[0004] In traditional oil and gas wells, this water is brought to the surface along with oil or gas at elevated temperatures. This mixture contains salts which when cooled at the earth’s surface will form scale within equipment which leads to significant costs from repairs and downtime. Accordingly, there is a need in the art for anti-scaling compositions and methods forPATENT APPLICATION Attorney Docket No.: 364.1528PC their use that can be used in the gas, oil, or geothermal production cycle which will inhibit and preferably prevent the formation of scale during the extraction or use of groundwater, produced water, and / or geothermal fluids. SUMMARY OF THE INVENTION

[0005] This section provides a general summary of the disclosure and is not a comprehensive disclosure of its full scope or all its features.

[0006] The present invention generally relates to methods and compositions for controlling the formation of scale in hydrocarbon extraction and / or geothermal applications, industrial water treatment or pulp and paper manufacturing. The present invention further relates to an anti-scaling composition that inhibits the formation of scale in oil fields and / or geoengineering applications. The composition consists essentially of: a copolymer that includes at least one moiety from monomer group A, at least one moiety from monomer group B, and may contain one or more monomers from group C. Group A contains ethylenically unsaturated carboxylic acid monomers which can include, but are not limited to, acrylic acid, methacrylic acid, 2-ethylacrylic acid, α- chloro-acrylic acid, α-cyano acrylic acid, β-methyl-acrylic acid (crotonic acid), α-phenyl acrylic acid, β-acryloxy propionic acid, sorbic acid, α-chloro sorbic acid, angelic acid, 2-carboxyethyl (meth)acrylate, cinnamic acid, p-chloro cinnamic acid, β-styryl acrylic acid (1-carboxy-4-phenyl butadiene-1,3), itaconic acid, maleic acid, citraconic acid, mesaconic acid, glutaconic acid, aconitic acid, fumaric acid, tricarboxy ethylene, muconic acid, 2-acryloxypropionic acid. Group B includes but is not limited to at least one (i) sulfonated monomer, which can include but is not limited to 2-acrylamido-2-methyl propane sulfonic acid, vinyl sulfonic acid, sodium methallyl sulfonate, sulfonated styrene, allyloxybenzene sulfonic acid; (ii) a mono or di alkyl maleate and / or salts thereof; (iii) a phosphonate or phosphino-containing monomer or chain transfer agent which contains phosphorus, which can include but is not limited to vinyl phosphonic acid, sodium hypophosphite. Group C may include a copolymerizable monomer including but not restricted to hydroxyalkyl (meth)acrylate, alkyl esters of (meth)acrylates, polyethylene glycol, polypropylene glycol, styrene; AND a chelating agent selected from the group of glutamic acid N,N-diacetic acid or a salt thereof (GLDA), aspartic acid N,Ndiacetic acid or a salt thereof (ASDA), methylglycine N,N-diacetic acid or a salt thereof (MGDA), and N-hydroxyethyl ethylenediamine N,N' ,N'-PATENT APPLICATION Attorney Docket No.: 364.1528PC triacetic acid or a salt thereof (HEDTA) and diethylenetriamine pentaacetic acid or a salt thereof (DTPA) and combinations thereof.

[0007] The present invention further relates to an anti-scaling composition that inhibits the formation of scale in oil fields, industrial water systems, pulp and paper processing system, and / or geoengineering applications. The anti-scaling composition as described above comprises greater than about 0.5 parts by weight of an AMPS moiety and / or MMM moiety per one hundred parts by weight of the polymer. The anti-scaling composition when used, it used has a concentration of one hundred to one million parts by weight of the polymer.

[0008] The present invention further relates to a method of reducing scaling in an oil field and / or thermal geoengineering application comprising the step of applying the anti-scaling composition described above in the oil field or in the thermal geoengineering application. Applying the anti-scaling composition can be applying the anti-scaling composition within the well and / or pipeline.

[0009] The present invention further relates to a method described above for reducing scaling in an oil field. The oil field and / or thermal geoengineering application produces a water stream and the step of applying the anti-scaling composition comprises applying the anti-scaling composition to the water stream at a temperature of greater than 300° C and preferably from about 100° to about 300° C. Further, the water stream can include a metal chosen from Ba, Ag, Sr, Ca, Mg, Mn, Fe, Cd, Cr, Co, Zn, Pb, Ni, Cu, Al, and combinations thereof.

[0010] The compositions and methods described above where the anti-scaling composition inhibits the formation of calcium carbonate, calcium sulfate, barium sulfate, iron carbonate and / or iron sulfide scale. Further areas of applicability will become apparent from the description provided herein. The description and specific examples in this summary are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure. BRIEF DESCRIPTION OF DRAWINGS

[0011] The drawings described herein are for illustrative purposes only of selected embodiments and not all possible implementations and are not intended to limit the scope of the present disclosure.PATENT APPLICATION Attorney Docket No.: 364.1528PC

[0012] Figure 1, represents test results depicting the effectiveness of scale inhibitors (SI) (and functional part / monomers) that give this synergy with chelates, several dynamic tube blocking tests performed at the same experimental conditions.

[0013] Figures 2a and 2b, represent Static bottle tests performed at room temperature, and bottle tests conducted at 130°C to evaluate the performance of SI+ chelate combo solution.

[0014] Figures 3a and 3b. represent test results depicting the effectiveness of scale inhibitors MIC determination for SI-2 (a) and SI-6 (b) using dynamic tube blocking equipment according to the present teachings.

[0015] Figure 4. represents test results depicting the effectiveness of scale inhibitors and the impact of temperature on the performance of scale inhibitors for CaCO3inhibition.

[0016] Figure 5. represents test results depicting the effectiveness of scale inhibitors and the synergistic effect of a chelate on scale inhibitor performance for inhibiting CaCO3 scale at 130°C.

[0017] Figure 6. represents test results depicting the effectiveness of scale inhibitors and the synergistic effect of a chelate on scale inhibitor performance for inhibiting CaCO3 scale at 130 °C and 170°C.

[0018] Figure 7. represents test results depicting the effectiveness of scale inhibitors and the synergistic effect of a chelate on scale inhibitor performance for inhibiting CaSO4 scale at 130°C.

[0019] Figures 8A-8C represent SEM diagrams of the crystal morphology of the precipitated CaCO3in a) blank test, b) with scale inhibitor, and c) with the treatment fluid or the present invention.

[0020] Figure 9. represents the dissolution capacity of the concentrated treatment fluid for descaling of CaCO3scale at various temperatures.

[0021] Figure 10. represents components of a scale inhibiting treatment fluid for according to the present teachings.

[0022] Figure 11. represents alternate components of a scale inhibiting treatment fluid for according to the present teachings.

[0023] Figure 12. Is a schematic of the dynamic tube blocking equipment used in this study.PATENT APPLICATION Attorney Docket No.: 364.1528PC DETAILED DESCRIPTION

[0024] According to the present teachings, an anti-scaling composition (SI), that inhibits the formation of scale in oil fields and / or geoengineering applications or removes scaling within a system is presented. The composition consists essentially of a polymer that is the reaction product of (A) an acrylate monomer and (B) 2-acrylamido-2-methyl propane sulfonic acid (AMPS) and / or monomethyl maleate (MMM); and methylglycine N, N- diacetic acid and / or salts thereof. The polymer can include greater than about 0.5 parts by weight of an ATBS moiety and / or MMM moiety per one million parts by weight of the polymer. Further, the polymer of the anti-scaling composition includes greater than about 5 parts by weight of an ATBS moiety and / or MMM moiety per one million parts by weight of the polymer. The anti-scaling composition inhibits the formation of calcium carbonate, calcium sulfate, barium sulfate, iron carbonate and / or iron sulfide scale.

[0025] The copolymer can have a weight average molecular weight (Mw) of from about 1000 to about 100000 g / mol, or a weight average molecular weight (Mw) of from about 2000 to about 50,000 g / mol or preferably a weight average molecular weight (Mw) of from about 3000 to about 25000 g / mol. Optionally, the composition contains methylglycine N, N- diacetic acid (MGDA) and / or salts thereof present in an amount of greater than about 5 parts by weight per one million parts by weight of the composition. The MGDA can be present in an amount greater than about 60 parts by weight per one million parts by weight of the composition.

[0026] In another teaching, an anti-scaling composition that inhibits the formation of scales (e.g. calcium carbonate, calcium sulfate, barium sulfate, iron carbonate, iron sulfide) in oil fields and / or geoengineering applications, the composition can consist of i) a polymer that is the reaction product of (A) an acrylate monomer and (B) acrylamide tertiary-butyl sulfonic acid (ATBS) and / or monomethyl maleate (MMM); ii) a chelating agent; and iii) water. It is envisioned that the chelating agent is selected from the monomer of glutamic acid N,N-diacetic acid or a salt thereof (GLDA), aspartic acid N,N-diacetic acid or a salt thereof (ASDA), methylglycine N,N-diacetic acid or a salt thereof (MGDA), and N-hydroxyethyl ethylenediamine N,N',N'-triacetic acid or a salt thereof (HEDTA) and diethylenetriamine pentaacetic acid or a salt thereof (DTPA) and combinations thereof.PATENT APPLICATION Attorney Docket No.: 364.1528PC

[0027] Optionally, the 2-acrylamido-2-methyl propane sulfonic acid (AMPS) and / or monomethyl maleate (MMM) of the composition can be >7% wt percent 2-acrylamido-2-methyl propane sulfonic acid (AMPS), or >10% wt 2-acrylamido-2-methyl propane sulfonic acid (AMPS), or >20% wt 2-acrylamido-2-methyl propane sulfonic acid (AMPS) or >10% wt Monomethyl maleate (MMM). Further, the polymer comprises greater than about 0.5 parts by weight of an AMPS moiety and / or MMM moiety per one hundred parts by weight of the polymer.

[0028] A method of reducing scaling in an oil field and / or thermal geoengineering application is disclosed. The method includes, applying the anti-scaling compositions disclosed herein in the oil field or in the thermal geoengineering application is applying the anti-scaling composition within the well and / or pipeline, and / or formation. Generally, the oil field and / or thermal geoengineering application produces a water stream. The anti-scaling composition can be added to the water stream which has a temperature of from about 100 to about 300° C. It is envisioned the water stream prior to treatment includes a metal chosen from Ba, Ag, Sr, Ca, Mg, Mn, Fe, Cd, Cr, Co, Zn, Pb, Ni, Cu, Al, and combinations thereof. The anti-scaling composition applied by this method inhibits the formation of calcium carbonate, calcium sulfate, barium sulfate, iron carbonate and / or iron sulfide scale.

[0029] Example embodiments will now be described more fully with reference to the accompanying drawings. The scale inhibitors used in this study were polyanionic polymers or copolymers used as such or used as a combination thereof. The chemical compositions of the scale inhibitors are generally described in Table 1. Each scale dissolver was a thermally stable polyanionic chelate.

[0030] For CaCO3inhibition tests, solutions of calcium chloride were mixed with a sodium bicarbonate solution either with or without a scale inhibitor / dissolver formulation. The composition of the anion and cation solution is shown in Table 2. The cation solution contains 1517 mg / kg Ca2+and has pH of 4.9. The anion solution contains 1198 mg / kg HCO3-and has pH of 8.3. For the CaSO4inhibition tests, cation and anion brines were mixed with or without the scale inhibitor / chelate formulation. The composition of the anion and cation solutions are shown in Table 3. The final ionic concentrations of each solution are given in Table 4.PATENT APPLICATION Attorney Docket No.: 364.1528PCPATENT APPLICATION Attorney Docket No.: 364.1528PC

[0031] For CaCO3inhibition tests, solutions of calcium chloride were mixed with a sodium bicarbonate solution either with or without a scale inhibitor formulation. Figure 1 represents test results depicting the effectiveness of scale inhibitors (and functional part / monomers) that give this synergy with MGDA. Several dynamic tube blocking tests were performed at the same exp. conditions. These materials were tested using the test apparatus and methods described below in the description of Figure 12 below. Shown are the results of a dynamic tube blocking test (DTB) with 1500 ppm Ca, 1200 ppm HCO3, and a 3mL / min flow rate. Shown are three general sets of test results. The first labelled “red” have no appreciable inhibition of scale formation.

[0032] Figures 2a and 2b. represent static bottle tests performed at room temperature, and bottle tests conducted at 130°C to evaluate the performance of SI+chelate combo solution. The performances of the scale inhibitors were first evaluated by bottle testing (jar test) at room temperature, 80°C and 130°C. In these tests, anion and cation solutions were mixed in 1:1 vol / vol ratio (i.e., 50%:50%). For the test at higher temperatures (e.g. 80 °C), the bottles were placed in an oven at the desired temperature after mixing at room temperature. For testing at 130°C, a Parr bomb was used to maintain the pressure at high temperature with an empty glass vial placed inside the parr pump to visualize any scale / precipitation formed during the test. The inhibitors were screened based on the precipitation visually observed after the tests. The static bottle tests were used as preliminary simple screening.

[0033] Figures 3a and 3b. represent test results depicting the effectiveness of scale inhibitors and to determine the minimum inhibitor concentration (MIC) for SI-2 (a) and SI-6 (b) usingPATENT APPLICATION Attorney Docket No.: 364.1528PC dynamic tube blocking equipment according to the present teachings. After the static tests, the dynamic behavior of the scale inhibitors was studied using dynamic tube blocking equipment. First, the MIC was determined for SI-2 and SI-6 at 80°C and 130°C. As shown in Figure 3, the MIC for SI-2 is 2.5 ppm and for SI-6, it is 10 ppm. According to these results, SI-2 and SI-6 can both inhibit CaCO3 scaling at 80°C without additional boosting by chelates. In this case, the preferred chelate is MGDA.

[0034] Figure 4. represents test results depicting the effectiveness of scale inhibitors and the impact of temperature on the performance of scale inhibitors for CaCO3 inhibition. The MIC values of scale inhibitors are a function of temperature. To investigate the effect of temperature on the performance of scale inhibitors, the dynamic tests were repeated with the same inhibitor concentration at two different temperatures of 80°C and 130°C. Figure 4 illustrates the performance of 5 ppm of SI-2 and 10 ppm of SI-6. As exhibited, both inhibitors cannot constrain the CaCO3scale formation at the elevated temperature from 80°C to 130°C, therefore higher concentration is needed.

[0035] Figure 5. represents test results depicting the effectiveness of scale inhibitors and the synergistic effect of a chelate on scale inhibitor performance for inhibiting CaCO3scale at 130°C. The synergistic effect of chelates on the performance of scale inhibitors was also investigated by running the DTB test separately for the scale inhibitor, the chelate, and the combined solution. Figure 5 shows the results of tube blocking for a blank test (no inhibitor or chelate) as well as tests with 60 ppm chelate only, 5 ppm SI-2 only, and the combined solution. As depicted, neither a single dosage of scale inhibitor nor chelate alone could prevent or postpone the CaCO3 scale formation, while the scale inhibitor / chelate combination postponed scale precipitation for at least 60 minutes under test conditions.

[0036] Figure 6. represents test results depicting the effectiveness of scale inhibitors and the synergistic effect of MGDA on scale inhibitor performance for inhibiting CaCO3 scale at 130 °C and 170°C. Since the preferred intended use for this development was high-temperature applications, the synergistic fluid was tested at 170°C as well. Figure 6 shows the dynamic inhibition behavior of SI-6 at 170°C. As seen, even triple dosage of SI-6 (i.e.30 ppm) was not able to control CaCO3precipitation and tube blockage. However, the synergistic fluid consists of scale inhibitor and chelate could successfully inhibit the CaCO3precipitation at 170°C. Table 6 shows the results obtained from the first screening test for CaSO4 inhibition at room temperature andPATENT APPLICATION Attorney Docket No.: 364.1528PC 80°C. As seen, among the eight scale inhibitors, SI-2, SI-4, and SI-6 delivered better performance to inhibit CaSO4 scale at 80°C.

[0037] Figure 7. represents test results depicting the effectiveness of scale inhibitors and the synergistic effect of a chelate on scale inhibitor performance for inhibiting CaSO4scale at 130°C. Figure 7 shows the results of the DTB test for a blank test (no inhibitor or chelate) as well as tests with 120 ppm chelate only, 10 ppm SI-6 only, and the combined solution. As pictured, neither a single dosage of scale inhibitor nor chelate could prevent or postpone the CaSO4scale formation, while the scale inhibitor / chelate combination postponed scale precipitation, showing the positive effect of chelate on inhibition performance.

[0038] Figures 8A-8C represent SEM diagrams of the crystal morphology of the precipitated CaCO3in a) blank test, b) with scale inhibitor, and c) with the new treatment fluid. These images represent the precipitation of scale at 130°C in the presence of the compound described above. APATENT APPLICATION Attorney Docket No.: 364.1528PC comparison was also made with the precipitated scale when only a scale inhibitor was present. Figure 8A shows the SEM images of CaCO3 scales a) in the blank test, b) with a scale inhibitor, and c) with the Scale inhibitor and Chelating agent according to the present teachings. The results found on the crystal morphology support the dynamic tube-blocking data. As shown, the calcite crystal shape can be significantly changed from cubic (Figure 8-a) to a smaller, rounded shape by adding a scale inhibitor (Figure 8-b). Despite this, crystals can grow / accumulate due to the unfilled attachment sites (seen as rough and uneven surfaces). In the test with the new treatment fluid, the calcite crystals are much more rounded in shape (Figure 8-c), lowering the chance of crystal growth and scaling.

[0039] Figure 9. Represents the dissolution capacity of the concentrated treatment fluid for descaling of CaCO3 scale at various temperatures. To measure the performance of the treatment fluid as scale dissolver at high temperatures, the dissolution capacity of the treatment fluid was measured. It is well known that for descaling applications, stoichiometric ratio of the dissolver is needed. Hence, to accurately measure the dissolution capacity, the same treatment fluid with high chelate concentration (around 20 w%) was used for these measurements. Figure 9 shows the maximum practical dissolution capacity of the concentrated treatment fluid for CaCO3descaling at various temperatures. As shown, dissolution capacity of >300 lbs / 1000gal (equivalent to >36 gr / liter) was obtained at 200°C.

[0040] It is evident that the dissolution capacity is less for the treatment fluid with lower chelate concentrations. The chelate content can be adjusted based on the expected already- precipitated scale.

[0041] Figure 10. represents the components of a scale inhibiting treatment fluid according to the present teachings. Specifically shown is the combination of the Chelate MGDA and the Components of scale inhibitors.

[0042] Figure 11. represents active components of a scale inhibiting treatment fluid according to the present teachings.

[0043] Figure 12. Represents a schematic of the dynamic tube-blocking equipment used to evaluate the materials. Dynamic tube blocking was used to evaluate the performance of qualified scale inhibitors by mimicking field conditions such as pressure and temperature. The brine compositions were synthesized in the same way as in the static test where they were separated into cation and anion solutions.PATENT APPLICATION Attorney Docket No.: 364.1528PC

[0044] The dynamic tube blocking system consists of two pumps for anion and cation solution injection, as shown in Figure 1. The scale inhibitor / chelate was added to the anion solution. For CaCO3tests, the flow rate for each pump was set to 1.5 ml / min, while for CaSO4, the injection rates were 0.75 ml / min (total of 1.5 ml / min). Both solutions were first passed through a pre-heating coil to warm up to the test desired temperature before mixing in a mixing chamber. In the mixing chamber, the solution was passed through a 1.5-meter capillary tubing. In all DTB tests, the pressure was kept at 20 bar using a back pressure regulator (BPR). During the test run, the pressure drop (DP) across the capillary tubing was monitored constantly. Any scale formed inside the capillary tube will change the pressure difference across the coil.

[0045] According to an embodiment, an anti-scaling composition that inhibits the formation of scale, is disclosed. The composition includes a polymer that is the reaction product of (A) at least one ethylenically unsaturated carboxylic acid monomer and (B) a second reactant chosen from the group selected from a sulfonated monomer, a mono or di alkyl maleate, a phosphonate containing monomer, a phosphino-containing monomer, and combinations thereof, and a chelating agent and a corrosion inhibitor.

[0046] Generally the corrosion inhibitors as specifically chosen to inhibit the corrosion of Cu and Fe for water treatment and / or oilfield. These can include a corrosion inhibitor selected from the group consisting of azoles (benzotriazole, tolyltrizazole), imidazolines, amines and combinations thereof. Optionally the anti-scaling composition can further include a copolymerizable monomer. The polymer comprises greater than about 0.5 parts by weight of a 2- acrylamido-2-methyl-1-propanesulfonicacid (AMPS) moiety and / or monomethyl maleate (MMM) moiety per 100 parts by weight of the polymer. Specifically, the polymer can include greater than about 5 parts by weight of an AMPS moiety and / or MMM moiety per 100 parts by weight of the polymer. The polymer has a weight average molecular weight (Mw) of from about 1000 to about 100000 g / mol.

[0047] The chelating agent can be selected from the group of glutamic acid N,N-diacetic acid or a salt thereof (GLDA), aspartic acid N,Ndiacetic acid or a salt thereof (ASDA), methylglycine N,N-diacetic acid or a salt thereof (MGDA), and N-hydroxyethyl ethylenediamine N,N' ,N'- triacetic acid or a salt thereof (HEDTA) and diethylenetriamine pentaacetic acid or a salt thereof (DTPA) and combinations thereof. The methylglycine N, N- diacetic acid and / or salts thereof are present in an amount greater than about 1 part by weight per 100 parts by weight of saidPATENT APPLICATION Attorney Docket No.: 364.1528PC composition. Optionally, the methylglycine N, N- diacetic acid and / or salts thereof is present in an amount greater than about 2 parts by weight per 100 parts by weight of said composition. The monomer A is chosen from (meth)acrylic Acid (AA), Maleic Acid(MA), itaconic acid, and combinations thereof. The anti-scaling compositions disclosed above, can be used to reduce scale or descale pipes in the oil field, in a thermal geoengineering application, water treatment process, or pulp and paper process. The method of controlling scale in oil field and / or thermal geoengineering applications includes the step of mixing the anti-scaling composition within the well at at temperatures of greater than 100° C. Specifically the anti-scaling composition is mixed with the to the water stream at a temperature of from about 100 to about 300° C. Often the the stream comprises a metal chosen from Ba, Ag, Sr, Ca, Mg, Mn, Fe, Cd, Cr, Co, Zn, Pb, Ni, Cu, Al, and combinations thereof. According to the further teachings, the anti-scaling composition inhibits the formation of calcium carbonate, calcium sulfate, barium sulfate, iron carbonate and / or iron sulfide scale.

[0048] An anti-scaling composition that inhibits the formation of CaCO3 and CaSO4 in oil fields or geoengineering applications, said composition contains: i A monomer selected from the group consisting of ethylenically unsaturated carboxylic acid monomer and; ii) a second reactant chosen from the group selected from a sulfonated monomer, a mono or di alkyl maleate, a phosphonate containing monomer, a phosphino-containing monomer, and combinations thereof; and a corrosion inhibitor.

[0049] The anti-scaling composition further can contain a chelating agent is selected from the monomer of glutamic acid N,N-diacetic acid or a salt thereof (GLDA), aspartic acid N,N-diacetic acid or a salt thereof (ASDA), methylglycine N,N-diacetic acid or a salt thereof (MGDA), and N- hydroxyethyl ethylenediamine N,N',N'-triacetic acid or a salt thereof (HEDTA) and diethylenetriamine pentaacetic acid or a salt thereof (DTPA) and combinations thereof. Optionally, the chelating agent is methylglycine N, N- diacetic acid or salts thereof. The monomer ii) in the polymer is greater than 1% wt percent 2-acrylamido-2-methyl-1-propanesulfonicacid (AMPS). The composition can contain greater than 2 wt percent 2-acrylamido-2-methyl-1- propanesulfonicacid (AMPS), greater than 5 wt percent 2-acrylamido-2-methyl-1- propanesulfonicacid (AMPS), and / or greater than 1 wt percent Monomethyl maleate (MMM). Optionally, the polymer can include greater than about 0.5 parts by weight of an AMPS moiety and / or MMM moiety per 100 parts by weight of the polymer.PATENT APPLICATION Attorney Docket No.: 364.1528PC

[0050] The foregoing description of the embodiments has been provided for purposes of illustration and description. It is not intended to be exhaustive or to limit the disclosure. Individual elements or features of a particular embodiment are generally not limited to that embodiment, but, where applicable, are interchangeable and can be used in a selected embodiment, even if not specifically shown or described. The same may also be varied in many ways. Such variations are not to be regarded as a departure from the disclosure, and all such modifications are intended to be included within the scope of the disclosure.

Claims

PATENT APPLICATION Attorney Docket No.: 364.1528PC Claims 1. An anti-scaling composition that inhibits the formation of scale, said composition comprising of: a polymer that is the reaction product of (A) at least one ethylenically unsaturated carboxylic acid monomer and (B) a second reactant chosen from at least one of a sulfonated monomer, a mono or di alkyl maleate, a phosphonate or phosphino-containing monomer and a chelating agent and a corrosion inhibitor.

2. The anti-scaling composition according to Claim 1, wherein the corrosion inhibitors for include a corrosion inhibitor selected from the group consisting of azoles (benzotriazole, tolyltrizazole), imidazolines, amines and combinations thereof 3. The anti-scaling composition according to Claim 1, further comprising a copolymerizable monomer 4. The anti-scaling composition according to Claim 1, wherein the polymer comprises one of greater than about 0.5 parts by weight of a 2-acrylamido-2-methyl-1- propanesulfonicacid (AMPS) moiety and monomethyl maleate (MMM) moiety per 100 parts by weight of the polymer.

5. The anti-scaling composition according to Claim 1, wherein the polymer comprises one of greater than about 5 parts by weight of an AMPS moiety and MMM moiety per 100 parts by weight of the polymer.

6. The composition of Claim 1, wherein the chelating agent is selected from the group of glutamic acid N,N-diacetic acid or a salt thereof (GLDA), aspartic acid N,Ndiacetic acid or a salt thereof (ASDA), methylglycine N,N-diacetic acid or a salt thereof (MGDA), and N-hydroxyethyl ethylenediamine N,N' ,N'-triacetic acid or a salt thereof (HEDTA) and diethylenetriamine pentaacetic acid or a salt thereof (DTPA) and combinations thereof.PATENT APPLICATION Attorney Docket No.: 364.1528PC 7. The composition of Claim 1, wherein one of said methylglycine N, N- diacetic acid and salts thereof is present in an amount of greater than about 1 part by weight per 100 parts by weight of said composition.

8. The composition of Claim 1, wherein one of methylglycine N, N- diacetic acid and salts thereof is present in an amount greater than about 2 parts by weight per 100 parts by weight of said composition.

9. The composition of Claim 1, wherein the monomer A is chosen from (meth)acrylic Acid (AA), Maleic Acid(MA), itaconic acid, and combinations thereof.

10. A method of reducing scaling in an underground process comprising mixing the composition of Claim 1 with a water-source having a temperature above 100 degrees C.

11. The method of claim 10 scaling in an underground process comprises a well and said step of applying is further defined as applying the anti-scaling composition within the well.

12. The method of claim 10 wherein the application produces a water stream and said step of applying the anti-scaling composition to the water stream at a temperature of from about 100° C to about 300° C.

13. The method of claim 10 wherein the water stream comprises a metal chosen from Ba, Ag, Sr, Ca, Mg, Mn, Fe, Cd, Cr, Co, Zn, Pb, Ni, Cu, Al, and combinations thereof.

14. The method of claim 13 wherein the composition inhibits the formation of scale selected from the group consisting of calcium carbonate, calcium sulfate, barium sulfate, iron carbonate, iron sulfide scale and combinations thereof.PATENT APPLICATION Attorney Docket No.: 364.1528PC 15. An anti-scaling composition that inhibits the formation of CaCO3 and CaSO4 in applications, said composition consisting of: i. a polymer that is the reaction product of (A) an acrylate monomer and (B) one of 2-acrylamido-2-methyl-1-propanesulfonicacid (AMPS) and monomethyl maleate; ii. a chelating agent.

16. The anti-scaling composition according to Claim 15 wherein the chelating agent is selected from the monomer of glutamic acid N,N-diacetic acid or a salt thereof (GLDA), aspartic acid N,N-diacetic acid or a salt thereof (ASDA), methylglycine N,N-diacetic acid or a salt thereof (MGDA), and N-hydroxyethyl ethylenediamine N,N',N'-triacetic acid or a salt thereof (HEDTA) and diethylenetriamine pentaacetic acid or a salt thereof (DTPA) and combinations thereof.

17. The composition of claim 15 wherein the chelating agent is methylglycine N, N- diacetic acid.

18. The composition of claim 15 wherein monomer B in the polymer is >1% wt percent 2- acrylamido-2-methyl-1-propanesulfonicacid (AMPS).

19. The composition of claim 15 consists of >2 wt percent 2-acrylamido-2-methyl-1- propanesulfonicacid (AMPS) 20. The composition of claim 15 consists of >1 wt percent Monomethyl maleate (MMM).

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