COMPOSITION INCLUDING BETA-GLUCAN AND ENZYME AND REACTION

PRODUCTS THEREOF

BACKGROUND

[0001] Beta-glucans can be used as thickeners in aqueous fluids for treatment of subterranean formations, such as for enhanced oil recovery (EOR). However, aqueous solutions including conventional beta-glucans can suffer from high elasticities (e.g., high pressure drop when passing from broader to narrower passages) and can clog the pores of subterranean formations. Conventional beta-glucans can have undesirably large particle sizes.

SUMMARY OF THE INVENTION

[0002] Various aspects of the present invention provide an aqueous composition including starting material beta-glucan and an enzyme.

[0003] Various aspects of the present invention provide an aqueous salt water composition that includes a starting material beta-glucan that is scleroglucan. The composition also includes an enzyme that is Aspergillus oryzae protease, Subtilisin A, Proteinase K, or a combination thereof.

[0004] Various aspects of the present invention provide an enzyme-treated beta- glucan that is a reaction product of the enzyme and the starting material beta-glucan in the aqueous composition.

[0005] Various aspects of the present invention provide a method of making the enzyme-treated beta-glucan. The method includes reacting the aqueous composition including starting material beta-glucan and an enzyme to provide the enzyme-treated beta- glucan.

[0006] Various aspects of the present invention provide a method of treating a starting material beta-glucan to improve its properties for treatment of a subterranean formation. The method includes reacting a starting material beta-glucan with an enzyme to provide an enzyme-treated beta-glucan that is different than the starting material beta-glucan.

[0007] Various aspects of the present invention provide a method of treating a subterranean formation with the aqueous composition. The method includes placing the aqueous composition including starting material beta-glucan and an enzyme in the subterranean formation. [0008] Various aspects of the present invention provide a method of treating a subterranean formation with the enzyme-treated beta-glucan. The method includes placing the enzyme-treated beta-glucan in the subterranean formation.

[0009] Various aspects of the present invention provide a use of the enzyme-treated beta-glucan for treatment of a subterranean formation.

[0010] Various aspects of the present invention provide certain advantages over other beta-glucans, methods of making the same, and methods of treating subterranean formations therewith. For example, in various aspects, aqueous solutions of the enzyme-treated beta- glucan of the present invention can have better rheological properties for treatment of subterranean formations as compared to aqueous solutions including other beta-glucans, such as lower elasticity and less pressure drop when passing from wider to narrower passages. In various aspects, the enzyme-treated beta-glucan of the present invention can have a smaller particle size as compared to other beta-glucans. In various aspects, aqueous solutions including the enzyme-treated beta-glucan of the present invention can cause less clogging of pores in a subterranean formation over time (e.g., a lower Filterability Ratio), as compared to aqueous solutions including other beta-glucans. In various aspects, the method of the present invention of forming the enzyme-treated beta-glucan can be a more efficient way to produce a beta-glucan having the desirable properties of the enzyme-treated beta-glucan (e.g., for treatment of subterranean formations) than other methods.

BRIEF DESCRIPTION OF THE FIGURES

[0011] The drawings illustrate generally, by way of example, but not by way of limitation, various aspects of the present invention.

[0012] FIG. 1 illustrates volume percent versus diameter for various beta-glucan samples, in accordance with various aspects.

[0013] FIG. 2 illustrates volume percent versus diameter for various beta-glucan samples, in accordance with various aspects.

[0014] FIG. 3 illustrates volume percent versus diameter for various beta-glucan samples, in accordance with various aspects.

[0015] FIG. 4 illustrates volume percent versus diameter for various beta-glucan samples, in accordance with various aspects. DETAILED DESCRIPTION OF THE INVENTION

[0016] Reference will now be made in detail to certain aspects of the disclosed subject matter. While the disclosed subject matter will be described in conjunction with the enumerated claims, it will be understood that the exemplified subject matter is not intended to limit the claims to the disclosed subject matter.

[0017] Throughout this document, values expressed in a range format should be interpreted in a flexible manner to include not only the numerical values explicitly recited as the limits of the range, but also to include all the individual numerical values or sub-ranges encompassed within that range as if each numerical value and sub-range is explicitly recited. For example, a range of "about 0.1% to about 5%" or "about 0.1% to 5%" should be interpreted to include not just about 0.1% to about 5%, but also the individual values (e.g., 1%, 2%, 3%, and 4%) and the sub-ranges (e.g., 0.1% to 0.5%, 1.1% to 2.2%, 3.3% to 4.4%) within the indicated range. The statement "about X to Y" has the same meaning as "about X to about Y," unless indicated otherwise. Likewise, the statement "about X, Y, or about Z" has the same meaning as "about X, about Y, or about Z," unless indicated otherwise.

[0018] In this document, the terms "a," "an," or "the" are used to include one or more than one unless the context clearly dictates otherwise. The term "or" is used to refer to a nonexclusive "or" unless otherwise indicated. The statement "at least one of A and B" has the same meaning as "A, B, or A and B." In addition, it is to be understood that the phraseology or terminology employed herein, and not otherwise defined, is for the purpose of description only and not of limitation. Any use of section headings is intended to aid reading of the document and is not to be interpreted as limiting; information that is relevant to a section heading may occur within or outside of that particular section. All publications, patents, and patent documents referred to in this document are incorporated by reference herein in their entirety, as though individually incorporated by reference. In the event of inconsistent usages between this document and those documents so incorporated by reference, the usage in the incorporated reference should be considered supplementary to that of this document; for irreconcilable inconsistencies, the usage in this document controls.

[0019] In the methods described herein, the acts can be carried out in any order without departing from the principles of the invention, except when a temporal or operational sequence is explicitly recited. Furthermore, specified acts can be carried out concurrently unless explicit claim language recites that they be carried out separately. For example, a claimed act of doing X and a claimed act of doing Y can be conducted simultaneously within a single operation, and the resulting process will fall within the literal scope of the claimed process.

[0020] The term "about" as used herein can allow for a degree of variability in a value or range, for example, within 10%, within 5%, or within 1% of a stated value or of a stated limit of a range, and includes the exact stated value or range.

[0021] The term "substantially" as used herein refers to a majority of, or mostly, as in at least about 50%, 60%, 70%, 80%, 90%, 95%, 96%, 97%, 98%, 99%, 99.5%, 99.9%, 99.99%, or at least about 99.999% or more, or 100%. The term "substantially free of as used herein can mean having none or having a trivial amount of, such that the amount of material present does not affect the material properties of the composition including the material, such that the composition is about 0 wt% to about 5 wt% of the material, or about 0 wt% to about 1 wt%, or about 5 wt% or less, or less than, equal to, or greater than about 4.5 wt%, 4, 3.5, 3, 2.5, 2, 1.5, 1, 0.9, 0.8, 0.7, 0.6, 0.5, 0.4, 0.3, 0.2, 0.1, 0.01, or about 0.001 wt% or less. The term "substantially free of can mean having a trivial amount of, such that a composition is about 0 wt% to about 5 wt% of the material, or about 0 wt% to about 1 wt%, or about 5 wt% or less, or less than, equal to, or greater than about 4.5 wt%, 4, 3.5, 3, 2.5, 2, 1.5, 1, 0.9, 0.8, 0.7, 0.6, 0.5, 0.4, 0.3, 0.2, 0.1, 0.01, or about 0.001 wt% or less, or about 0 wt%.

[0022] The term "standard temperature and pressure" as used herein refers to 20 °C and 101 kPa.

[0023] The term "downhole" as used herein refers to under the surface of the earth, such as a location within or fluidly connected to a wellbore.

[0024] As used herein, the term "subterranean material" or "subterranean formation" refers to any material under the surface of the earth, including under the surface of the bottom of the ocean. For example, a subterranean formation or material can be any section of a wellbore and any section of a subterranean petroleum- or water-producing formation or region in fluid contact with the wellbore. Placing a material in a subterranean formation can include contacting the material with any section of a wellbore or with any subterranean region in fluid contact therewith. Subterranean materials can include any materials placed into the wellbore such as cement, drill shafts, liners, tubing, casing, or screens; placing a material in a subterranean formation can include contacting with such subterranean materials. In some examples, a subterranean formation or material can be any below-ground region that can produce liquid or gaseous petroleum materials, water, or any section below-ground in fluid contact therewith. For example, a subterranean formation or material can be at least one of an area desired to be fractured, a fracture or an area surrounding a fracture, and a flow pathway or an area surrounding a flow pathway, wherein a fracture or a flow pathway can be optionally fluidly connected to a subterranean petroleum- or water-producing region, directly or through one or more fractures or flow pathways.

[0025] As used herein, "treatment of a subterranean formation" can include any activity directed to extraction of water or petroleum materials from a subterranean petroleum- or water-producing formation or region, for example, including drilling, stimulation, hydraulic fracturing, clean-up, acidizing, completion, cementing, remedial treatment, abandonment, water shut-off, conformance, and the like.

[0026] As used herein, a "flow pathway" downhole can include any suitable subterranean flow pathway through which two subterranean locations are in fluid connection. The flow pathway can be sufficient for petroleum or water to flow from one subterranean location to the wellbore or vice- versa. A flow pathway can include at least one of a hydraulic fracture, and a fluid connection across a screen, across gravel pack, across proppant, including across resin-bonded proppant or proppant deposited in a fracture, and across sand. A flow pathway can include a natural subterranean passageway through which fluids can flow. In some aspects, a flow pathway can be a water source and can include water. In some aspects, a flow pathway can be a petroleum source and can include petroleum. In some aspects, a flow pathway can be sufficient to divert from a wellbore, fracture, or flow pathway connected thereto at least one of water, a downhole fluid, or a produced hydrocarbon.

Aqueous composition including starting material beta-glucan.

[0027] Various aspects of the present invention provide an aqueous composition including starting material beta-glucan (e.g., one or more beta-glucans) and an enzyme (e.g., one or more enzymes). The aqueous composition can be sufficient such that under certain reaction conditions the starting material beta-glucan and the enzyme react to form an enzyme-treated beta-glucan, such as any enzyme-treated beta-glucan formed herein.

[0028] The composition can include one enzyme or more than one enzyme. A manufacturer's solution including the enzyme can be any suitable proportion of the composition, such as about 0.001 wt% to about 10 wt% of the composition, 0.1 wt% to about 0.5 wt% of the composition, 0.2 wt% to about 0.25 wt% of the composition, or about 0.001 wt% or less, or less than, equal to, or greater than about 0.01 wt%, 0.05, 0.1, 0.15, 0.16, 0.17, 0.18, 0.19, 0.2, 0.21, 0.22, 0.23, 0.24, 0.25, 0.26, 0.27, 0.28, 0.29, 0.3, 0.35, 0.4, 0.45, 0.5, 0.6, 0.7, 0.8, 0.9, 1, 1.5, 2, 2.5, 3, 3.5, 4, 5, 6, 8, or about 10 wt% or more. The one or more enzymes can be any suitable proportion of the composition, such as about 0.000,001 wt% to about 10 wt% of the composition, or about 0.000,001 wt% or less, or less than, equal to, or greater than about 0.000,01 wt%, 0.000,1, 0.001, 0.01, 0.1, 1, 1.5, 2, 2.5, 3, 3.5, 4, 5, 6, 8, or about 10 wt% or more. The one or more enzymes can be present in the composition in an amount that is any suitable weight ratio with the amount of starting material beta-glucan in the composition, such as wherein a manufacturer' s solution including the enzyme is about 0.1 to about 100 times of the amount of the starting material beta-glucan present in the composition, by weight, or about 2 to about 2.5 times, or about 0.1 times or less, or less than, equal to, or greater than about 0.2 times, 0.4, 0.6, 0.8, 1, 1.5, 2, 2.5, 3, 4, 5, 6, 8, 10, 15, 20, 25, 30, 40, 50, 60, 70, 80, 90, or about 100 times or more. The one or more enzymes can be any suitable enzymes that are reactive with the beta-glucan to form an enzyme-treated beta- glucan that is different than the starting material beta-glucan (e.g., that is chemically different, that has different physical or chemical properties, or a combination thereof). The one or more enzymes can be Aspergillus oryzae protease (e.g., from a manufacturer's solution including greater than or equal to 500 units/g, wherein the units for this enzyme are defined in the Examples), Subtilisin A (e.g., from a manufacturer's solution including greater than 10 units/mg, wherein the units for this enzyme are defined in the Examples), Proteinase K (e.g., from a manufacturer's solution including greater than 800 units/mL, wherein the units for this enzyme are defined in the Examples), or a combination thereof.

[0029] The composition can include one starting material beta-glucan or more than one starting material beta-glucan. The one or more starting material beta-glucans can be any suitable proportion of the composition, such as 0.001 wt% to about 50 wt% of the composition, 0.01 wt% to about 1 wt%, about 0.05 wt% to about 0.15 wt%, or about 0.001 wt% or less, or less than, equal to, or greater than about 0.01 wt%, 0.05, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1, 1.5, 2, 2.5, 3, 3.5, 4, 5, 6, 8, 10, 15, 20, 25, 30, 35, 40, 45, or about 50 wt% or more of the composition. The starting material beta-glucan can be an isolated beta- glucan (e.g., purified at least to some degree from a fermentation broth that contained beta- glucan during formation thereof) or a crude beta-glucan (e.g., an unpurified beta-glucan that includes contaminants from the fermentation broth, or that is still in the original fermentation broth). The beta-glucan can be homogeneously or heterogeneously distributed in the aqueous composition. The beta-glucan can be dissolved in the composition (e.g., no solid particles present as determined by visial detection), partially dissolved, or can be in a powdered solid form in the composition (e.g., a suspension of the beta-glucan). [0030] The beta-glucan can be a 1,3 beta-glucan. The beta-glucan can be a 1,3-1,6 beta-D-glucan. The beta-glucan can be a 1,3-1,4 beta-D-glucan, such as having a main chain from beta-l,3-glycosidically bonded glucose units, and side groups which are formed from glucose units and are beta-l,6-glycosidically bonded thereto. Examples of such 1,3 beta-D- glucans include curdlan (a homopolymer of beta-(l,3)-linked D-glucose residues produced from, e.g., Agrobacterium spp.), grifolan (a branched beta-(l,3)-D-glucan produced from, e.g., the fungus Grifola frondosa), lentinan (a branched beta-(l,3)-D-glucan having two glucose branches attached at each fifth glucose residue of the beta-(l,3)-backbone produces from, e.g., the fungus Lentinus eeodes), schizophyllan (a branched beta-(l,3)-D-glucan having one glucose branch for every third glucose residue in the beta-(l,3)-backbone produced from, e.g., the fungus Schizophyllan commune), scleroglucan (a branched beta- (l,3)-D-glucan with one out of three glucose molecules of the beta-(l,3)-backbone being linked to a side D-glucose unit by a (l,6)-beta bond produced from, e.g., fungi of the Sclerotium spp.), SSG (a highly branched beta-(l,3)-glucan produced from, e.g., the fungus Sclerotinia sclerotiorum), soluble glucans from yeast (a beta-(l,3)-D-glucan with beta-(l,6)- linked side groups produced from, e.g., Saccharomyces cerevisiae), laminarin (a beta-(l,3)- glucan with beta-(l,3)-glucan and beta-(l,6)-glucan side groups produced from, e.g., the brown algae Laminaria digitata), and cereal glucans such as barley beta glucans (linear beta- (l,3)(l,4)-D-glucan produced from, e.g., Hordeum vulgare, Avena sativa, or Triticum vulgare).

[0031] The beta-glucan can be scleroglucan, a branched beta-glucan with one out of three glucose molecules of the beta-(l,3)-backbone being linked to a side D-glucose unit by a (l,6)-beta bond produced from, e.g., fungi of the Sclerotium. The beta-glucan can be schizophyllan, a branched beta-glucan having one glucose branch for every third glucose residue in the beta-(l,3)-backbone produced from, e.g., the fungus Schizophyllan commune. Fungal strains that secrete such glucans are known to those skilled in the art. Examples include Schizophyllum commune, Sclerotium rolfsii, Sclerotium glucanicum, Monilinla fructigena, Lentinula edodes, or Botrygs cinera. The beta-glucan can have desirable characteristics for treatment of subterranean formations as described in co-pending patent applications U.S. Provisional Application Serial Nos. 62/313,973, 62/313,988, 62/345,109, and 62/348,278, and U.S. Patent Publication No. 2012/0205099.

[0032] Water can be any suitable proportion of the aqueous composition. Water can be about 50 wt% to about 99.999 wt% of the aqueous composition, or about 99.5 wt% to about 99.9 wt%, or about 50 wt% or less, or less than, equal to, or greater than about 60 wt%, 65, 70, 75, 80, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 97.5, 98, 98.5, 99, 99.5, 99.9, 99.99 wt%, or about 99.999 wt% or more. The water can include fresh water, salt water, brine, produced water, flowback water, brackish water, sea water, synthetic sea water, or a combination thereof. For a salt water, the one or more salts therein can be any suitable salt, such as at least one of NaBr, CaCh, CaBr2, ZnB¾ KC1, NaCl, a carbonate salt, a sulfonate salt, sulfite salts, sulfide salts, a phosphate salt, a phosphonate salt, a magnesium salt, a sodium salt, a calcium salt, a bromide salt, a formate salt, an acetate salt, a nitrate salt, or a combination thereof. The water can have any suitable total dissolved solids level, such as about 1,000 mg/L to about 250,000 mg/L, or about 1,000 mg/L or less, or about 0 mg/L, or about 5,000 mg/L, 10,000, 15,000, 20,000, 25,000, 30,000, 40,000, 50,000, 75,000, 100,000, 125,000, 150,000, 175,000, 200,000, 225,000, or about 250,000 mg/L or more. The water can have any suitable salt concentration, such as about 1,000 ppm to about 300,000 ppm, or about 1,000 ppm to about 150,000 ppm, or about 800 ppm to about 1,000 ppm, or about 0 ppm, or about 500 ppm or less, or about 600 ppm, 700, 800, 900, 1,000, 1,100, 1,200, 1,300, 1,400, 1,500, 1,600, 1,800, 2,000, 2,500, 3,000, 3,500, 4,000, 5,000, 10,000, 15,000, 20,000, 25,000, 30,000, 40,000, 50,000, 75,000, 100,000, 125,000, 150,000, 175,000, 200,000, 225,000, 250,000, 275,000, or about 300,000 ppm or more. In some examples, the water can have a concentration of at least one of NaBr, CaCh, CaBr2, ZnB^, KC1, and NaCl of about 0.1% w/v to about 20% w/v, or about 0 %, or about 0.1% w/v or less, or about 0.5% w/v, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, or about 30% w/v or more.

Enzyme-treated beta-glucan.

[0033] Various aspects of the present invention provide an enzyme-treated beta- glucan that is a reaction product of the enzyme and the starting material beta-glucan in the aqueous composition. The enzyme-treated beta-glucan is different than the starting material beta-glucan, such as chemically different, having different physical or chemical properties (e.g., neat or in an aqueous solution), or a combination thereof.

[0034] The enzyme-treated beta-glucan can be in any suitable form. The enzyme- treated beta-glucan can be in a dry powder form, in a suspension (e.g., with aqueous solvents, non- aqueous solvents, or a combination thereof), or in a solution. The enzyme-treated beta- glucan can be in a solution, such as a solution generated from reaction of the aqueous composition including the starting material beta-glucan and the enzyme, that is free of purification or that has experienced at least some purification. [0035] An aqueous solution of the enzyme-treated beta-glucan can have different rheological characteristics as compared to an aqueous solution of the starting material beta- glucan at the same concentration and under the same conditions. For example, an aqueous solution of the enzyme-treated beta-glucan can have reduced elasticity as compared to an aqueous solution of the starting material beta-glucan at the same concentration and under the same conditions. An aqueous solution of the enzyme-treated beta-glucan can have a smaller pressure drop when pumped through a constriction (e.g., when pumped from a broader flow pathway to a narrower flow pathway) as compared to an aqueous solution of the starting material beta-glucan at the same concentration and under the same conditions.

[0036] The enzyme-treated beta-glucan can have a different particle size distribution as compared to the starting material beta-glucan under the same conditions. For example, the enzyme-treated beta-glucan can have a smaller volume mean particle size as compared to the starting material beta-glucan under the same conditions. The enzyme-treated beta-glucan can have a volume mean particle size of about 1 micron to about 1,000 microns, 1 micron to about 500 microns, 1 micron to about 150 microns, or about 30 micron to about 100 microns, or about 1 micron or less, or less than, equal to, or greater than about 2 microns, 3, 4, 5, 6, 8, 10, 15, 20, 25, 30, 40, 50, 75, 100, 125, 150, 175, 200, 250, 300, 400, 500, 750 microns, or about 1,0000 microns or more. The enzyme-treated beta-glucan can have a smaller D10, D50, D90, or combination thereof, as compared to the starting material beta-glucan under the same conditions.

[0037] An aqueous solution of the enzyme-treated beta-glucan can have a different

Filterability Ratio as compared to the Filterability Ratio of an aqueous solution of the starting material beta-glucan under the same conditions, such as a lower Filterability Ratio. The Filterability Ratio can be determined by the procedure described in the Examples. The Filterability Ratio indicates the degree to which the mixture causes pore clogging over time, and is a ratio of time required for 20 g flow at a steady pressure through a filter at a later time divided by the time required for 20 g flow through the filter at an earlier time, with a ratio of 1 indicating no pore clogging (e.g., equal times required for flow at later and earlier times through the same filter at the same pressure). The Filterability Ratio can be determined by passing the sample through a filter having a pore size of about 1.2 microns (e.g., 47 mm diameter, 1.2 μιη pore size, EMD Millipore mixed cellulose esters filter (part #

RAWP04700)) using a pressure to achieve a flux of about 1-3 g/s and maintaining such pressure consistently while measuring the mass of filtrate produced. The Filterability Ratio is (time(180 g) - time (160 g))/(time(80 g) - time (60 g)). Prior to passing the sample through the 1.2 micron filter, the sample can first be optionally passed through a filter having a pore size of about 2 microns (e.g., 47 mm diameter Millipore AP25 filter (AP2504700)) at about 100-300 mL/min. The sample can optionally be prepared by combining powdered refined beta-glucan with water in a concentration of 1 g/L, mixing at 700 rpm for 20 minutes, and then agitating at 2,000 rpm for 4 hours. An aqueous solution of the enzyme-treated beta- glucan can have a Filterability Ratio of about 0.9 to about 20, or about 1 to about 2, or about 1 to about 1.5, about 1.05 to about 1.3, or about 0.9 or less, or less than, equal to, or greater than about 1, 1.02, 1.04, 1.06, 1.08, 1.10, 1.12, 1.14, 1.16, 1.18, 1.20, 1.22, 1.24, 1.26, 1.28, 1.3, 1.35, 1.4, 1.45, 1.5, 1.6, 1.7, 1.8, 1.9, 2, 2.5, 3, 4, 5, 6, 8, 10, 12, 14, 16, 18, or about 20 or more.

Method of making enzyme-treated beta-glucan.

[0038] Various aspects of the present invention provide a method of making the enzyme-treated beta-glucan. The method includes reacting the aqueous composition including starting material beta-glucan and an enzyme to provide the enzyme-treated beta- glucan. The method of making the enzyme-treated beta-glucan can be a method of treating the starting material beta-glucan with the enzyme to improve its properties for treatment of a subterranean formation (e.g., for enhanced oil recovery).

[0039] The reacting can be performed at any suitable pH, such as about 3 to about 10, or about 6 to about 9, or about 3 or less, or less than, equal to, or greater than about 4, 5, 6, 7, 8, 9, or about 10 or more.

[0040] The reacting can be performed with any suitable agitation, and can include agitating the aqueous composition in any suitable way, such as at a suitable rpm, such as at about 0 rpm to about 2,000 rpm, or about 200 rpm to about 600 rpm, or about 50 rpm or less, or less than, equal to, or greater than about 75 rpm, 100, 150, 200, 300, 400, 500, 600, 700, 800, 900, 1,000, 1,500, or about 2,000 rpm or more.

[0041] The reacting can include subjecting the aqueous composition to or maintaining the aqueous composition at any suitable temperature, such as about 0 °C to about 100 °C, or about 10 °C to about 90 °C, or about 30 °C to about 70 °C, or about 0 °C or less, or less than, equal to, or greater than about 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95 °C, or about 100 °C or more. The temperature can be maintained for the duration of the reacting.

[0042] The reacting can be performed for any suitable duration, such as until the enzyme-treated beta-glucan is suitably formed at a desired conversion from the starting material beta-glucan, such as for about 1 second to about 2 weeks, or about 1 minute to about 1,000 minutes, or about 300 to about 400 minutes, or about 1 second or less, or less than, equal to, or greater than about 2 seconds, 5, 10, 30 seconds, 1 minute, 2, 3, 4, 5, 6, 8, 10, 15, 20, 25, 30, 40, 50, 60, 70, 80, 90, 100, 200, 300, 400, 500, 600, 800, 1,000, 2,000, 3,000, 4,000, 5,000, 6,000, 8,000, 10,000, 15,000 minutes, or about 2 weeks or more.

[0043] The method of making the enzyme-treated beta-glucan can include forming the aqueous composition including the beta-glucan starting material and the enzyme, or the aqueous composition can be provided prior to the onset of the method. Forming the aqueous composition can include shearing a composition including the starting material beta-glucan for at least about 0.01 s (e.g., for about 0.06 s to about 6 s, or about 0.01 s or less, or less than, equal to, or greater than about 0.02 s, 0.03, 0.04, 0.05, 0.06, 0.07, 0.08, 0.09, 0.1, 0.5, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, 25, 30, 40, 50 seconds, 1 minute, 2, 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, 25, 30, 40, 50 minutes, or about 1 hour or more), at a shear rate of about 40,000 s ¹ to about 300,000 s ¹ (e.g., about 40,000 s ¹ or less, or less than, equal to, or greater than about 50,000 s ^~ 60,000, 70,000, 80,000, 100,000, 120,000, 140,000, 160,000, 180,000, 200,000, 220,000, 240,000, 260,000, 280,000s ¹ , or about 300,000 s ¹ or more), and adding the enzyme (e.g., after the shearing, or before the shearing). The method of making the enzyme-treated beta- glucan can be performed above-surface, or in a subterranean formation (e.g., downhole).

Method of treating a starting material beta-glucan to improve the properties thereof.

[0044] Various aspects of the present invention provide a method of treating a starting material beta-glucan to improve its properties for treatment of a subterranean formation. The method includes reacting a starting material beta-glucan with an enzyme to provide an enzyme-treated beta-glucan that is different than the starting material beta-glucan. The method can include reacting the aqueous composition including the starting material beta- glucan and the enzyme such that the enzyme-treated beta-glucan is formed. The method can be performed above-surface or in a subterranean formation (e.g., downhole). The improved properties of the enzyme-treated beta-glucan are with respect to the starting material beta- glucan, and can with respect to the properties of the starting material beta-glucan in an aqueous solution as compared to the enzyme-treated beta-glucan in an aqueous solution under the same conditions. The improved properties can be any suitable properties, such as the properties described herein for the enzyme-treated beta-glucan, such as improved rheology, improved particle size, improved Filterability Ratio, or a combination thereof. Method of treating a subterranean formation.

[0045] Various aspects of the present invention provide a method of treating a subterranean formation with the aqueous composition. The method includes placing the aqueous composition including starting material beta-glucan and an enzyme in the subterranean formation. The method can further including reacting the starting material-beta glucan and the enzyme (e.g., in the subterranean formation) to produce an enzyme-treated beta-glucan, such as any enzyme-treated beta-glucan described herein.

[0046] Various aspects of the present invention provide a method of treating a subterranean formation with the enzyme-treated beta-glucan. The method includes placing the enzyme-treated beta-glucan in the subterranean formation.

[0047] As used herein, placing a composition in a subterranean formation can designate transporting the composition from above-surface to the subterranean formation, or can designate forming the composition within the subterranean formation. For example, placing a composition in the subterranean formation can designate providing the composition above surface and placing it downhole into the subterranean formation, or it can designate forming the composition in the subterranean formation (e.g., adding an enzyme to a starting material beta-glucan to form the aqueous composition, or reacting the starting material beta- glucan with the enzyme to form the enzyme-treated beta-glucan).

[0048] The method of treating the subterranean formation can include performing enhanced oil recovery (e.g., using an aqueous composition including the enzyme-reacted beta-glucan as a surfactant flood fluid or sweep fluid), hydraulic fracturing, water shut-off, conformance, or a combination thereof. In a hydraulic fracturing operation, the enzyme- treated beta-glucan can be used during any suitable stage of the hydraulic fracturing, such as during at least one of a pre-pad stage (e.g., during injection of water with no proppant, and additionally optionally mid- to low-strength acid), a pad stage (e.g., during injection of fluid only with no proppant, with some viscosifier, such as to begin to break into an area and initiate fractures to produce sufficient penetration and width to allow proppant-laden later stages to enter), or at a slurry stage of the fracturing (e.g., as viscous fluid including proppant).

[0049] Performing enhanced oil recovery in the subterranean formation can include using an aqueous composition including the enzyme-treated beta-glucan as a surfactant flooding fluid to sweep petroleum in the subterranean formation toward a well (e.g., a different well than the beta-glucan composition or a precursor thereto was injected into). The method can include removing the petroleum (e.g., at least some of the petroleum swept toward the well) from the well.

[0050] Various aspects of the present invention provide a use of the enzyme-treated beta-glucan for treatment of a subterranean formation.

Examples

[0051] Various aspects of the present invention can be better understood by reference to the following Examples which are offered by way of illustration. The present invention is not limited to the Examples given herein.

Example 1. Preparation of Samples.

[0052] Several liters of scleroglucan solution were made by solubilizing 1 g/L of

Actigum® CS-11 in 900 ppm NaCl water. The solution was subjected to 6 passes through an IKA® Magic Lab® in UTL configuration with a 4M rotor stator pair running unit at 26,000 rpm. The IKA ^® Magic Lab ^® is an inline mixer using a rotor stator to impart shear on the solution. As used herein, term "pass" through the Magic Lab denotes feeding solution to the Magic Lab and collecting it at the discharge, wherein the solution has been processed through the equipment one time. Each pass through the single rotor stator assembly of the Magic Lab subjected the Sample to a shear rate (s ¹ ) of about 10 times the rotor speed setting in rpm for a duration of about 0.01 s to about 1 s.

[0053] Samples were loaded into the reactors with enzyme within 4 hours, or held at

80°C, ahead of enzyme mixing to reduce contamination from biological hosts. Enzyme reactions were carried out in an Infors HT (Bottmingen, Switzerland) Sixfors unit. The unit consists of six independently controlled reactors, each with variable temperature control and a magnet driven agitator. The agitator shaft was held in place via a coupling on the headplate, and the agitator rotated in a removable bearing seated in the bottom of the glass reactor. The agitation shaft had two Rushton-type 6-blade impellers, which were positioned all the way at the bottom. The headplate was a stainless steel piece fitted with a sampling dip tube and a temperature probe. All other ports on the headplate were closed with stainless plugs, and all openings were sealed to prevent evaporation. The reactor vessels were approximately 1 liter in size, with a 500 mL working volume. The reactors were held in place with an adjustable clamp.

[0054] Scleroglucan solution (250 g total, 1,000 ppm scleroglucan in 0.9 wt% NaCl) was weighed into a tared Infors reaction vessel. The reactors were then fitted with a headplate and agitator shaft, sampling tube, and temperature probe. The reactors were placed into the Infors unit and the temperature and agitation parameters for each individual reaction were set. The pH of the scleroglucan solution was measured with pH paper to be 7, and for reactions that had pH values above or below 7, the pH was adjusted using IN NaOH and/or IN HC1. Final pH values were measured with pH paper.

[0055] Reactions were initiated after the individual reactors reached the target temperature. The headplate was removed and placed into secondary containment. Enzyme (500 microliters) was added to the reactor and mixed with an Ika Ultraturrax high-shear mixer at 7,000-13,000 rpm for 30 seconds. After the high shear mix step, the headplate was returned, and agitation in the vessel was restored to the reaction specific level (200-600 rpm). The reaction was then allowed to run for six hours. After six hours, glutaraldehyde was added to a final concentration of 1,000 ppm through an open port in the headplate, and mixed using the reactor's set agitation for 1-2 minutes. After dispersion of the glutaraldehyde, the reactions were transferred to 250 mL glass bottles. The bottles were capped and stored at room temperature until further analysis.

[0056] The first set of reactions were loaded within 4 hours of solution preparation and run with Aspergillus oryzae protease (EC 232-752-2) from Sigma Aldrich (catalog # P6110, greater than or equal to 500 units per gram wherein 1 unit is the amount which hydrolyzes 1 micromole of L-leucine-p-nitroanilide per minute) at the conditions shown in Table 1.

[0057] Table 1. Samples AOl-6.

[0058] The second set of reactions were stored overnight at 80 °C and run with

Subtilisin A (EC 3.4.21.62) enzyme from Megazyme (catalog # E-BSPRT-40ML, greater than 10 units per mg, wherein 1 unit hydrolyzes casein to produce color equivalent to one micromole (181 micrograms) of tyrosine per minute at pH 7.0 at 40 °C, wherein the color is by Folin-Ciocalteu reagent) at the conditions shown in Table 2.

[0059] Table 2. Samples SA1-6.

[0060] The third set of reactions were stored 36 hours at 80 °C and run with

Proteinase K (EC 3.4.21.64) was from Sigma Aldrich (catalog # P4850, greater than or equal to 10 mg/mL, greater than or equal to 800 units/mL, wherein 1 unit hydrolyzes urea- denatured hemoglobin to produce color equivalent to 1 micromole of tyrosine per min at pH 7.5 at 37 °C, with color by Folin-Ciocalteu reagent) at the conditions shown in Table 3.

[0061] Table 3. Samples PK1 -6.

Example 2. Evaluation of rheology - shear viscosity.

[0062] The Samples formed in Example 1 were analyzed at ambient conditions for shear viscosity using an Anton Paar MCR502 Controlled Stress Rheometer, including a Titanium Double Gap (26, 27mm diameter) probe and sample cup. The samples were conditioned in two intervals; 1) Pre-shear at 1 s ¹ for 1 minute to remove air bubbles; Data collected every 30 seconds and 2) Pre-condition (thermal and mechanically) sample at 0.01 s ^{~ 1} for 10 minutes with a linear data collection rate of 1 data point every minute. The samples then underwent an ascending shear rate sweep from 0.01 to 1000 s ¹ , 10 data points per log decade with a logarithmic data collection rate of 2 to 0.0167 minutes (longer times at slower rates). And finally, an ascending shear rate sweep from 1000 to 0.01 s ¹ , 10 data points per log decade with a logarithmic data collection rate of 0.0167 to 2 minutes (longer times at slower rates). The resulting data was captured from the ascending shear rate sweeps. The data is shown in Tables 4-7. Table 4 illustrates shear dependent viscosity data for Samples AOl-6. Table 5 illustrates shear dependent viscosity data for Samples SA1-6. Table 6 illustrates shear dependent viscosity data for Samples PKl-6. Table 7 illustrates harmonic viscosity data for Samples PKl-6.

[0063] Table 4. Shear dependent viscosity data for Samples AOl-6.

[0064] Table 5. Shear dependent viscosity data for Samples SAl-6.

[0065] Table 6. Shear dependent viscosity data for Samples PKl-6.

[0066] Table 7. Harmonic viscosity data for Samples PKl-6.

Example 3. Particle size.

[0067] The Samples made in Example 1 were added in to a Malvern Mastersizer 3000, analyzing transmission at 633 and 470 nm, which reported obscuration of the Samples (i.e., 1/transmittance). The particle size distribution results are shown in Table 8. FIGS. 1-4 illustrates volume percent versus diameter for the Samples.

[0068] Table 8. Particle Size Distribution Results. D 10, D50, and D90 is the particle diameter below which 10%, 50%, and 90%, of total volume exists, respectively. The volume mean is D[4,3], which equals∑ d ⁴ /∑ d ³ , wherein d is diameter. Diameter is given in microns.

Example 4. Filterability Ratio.

[0069] Filterability Ratio determination. A Pall stainless steel filter housing (4280) was assembled with a 47 mm diameter Millipore AP25 filter (AP2504700), having a pore size of 2 microns. For each sample, the dispersion was passed through the housing using a flow rate of 100-300 mL/min, and the filtered dispersion was used for future steps. The Pall stainless steel filter housing (4280) was assembled with 47 mm diameter, 1.2 μιη pore size, EMD Millipore mixed cellulose esters filter (part # RAWP04700), with >200 mL of solution. A container was placed on a mass balance for recording mass of material passing through the filter. Pressure was applied to the filter. The filter was unplugged and pressure was adjusted to achieve a target flux of 1-3 g/s. Once target flux was established, a constant pressure was maintained and the time needed to filter 60 g, 80 g, 160 g, and 180 g of solution through the filter was measured.

Filterability Ratio was determined as (time(180 g) - time (160 g))/(time(80 g) - time (60 g)). The elapsed time between the assembly of the Pall stainless steel filter with >200 mL of solution and the time to complete the passing of the 180 g solution through the filter took between 30 minutes and 4 hours. Results of the Filterability Ratio determination are shown in Table 9. The raw filterability data is given in Table 10.

[0070] Table 9. Filterability Ratio.

[0071] Table 10. Filterability data with 1.2 micron filter.

[0072] The terms and expressions that have been employed are used as terms of description and not of limitation, and there is no intention in the use of such terms and

expressions of excluding any equivalents of the features shown and described or portions thereof, but it is recognized that various modifications are possible within the scope of the present invention. Thus, it should be understood that although the present invention has been

specifically disclosed by specific aspects and optional features, modification and variation of the concepts herein disclosed may be resorted to by those of ordinary skill in the art, and that such modifications and variations are considered to be within the scope of the present invention.

Exemplary Aspects.

[0073] The following exemplary aspects are provided, the numbering of which is not to be construed as designating levels of importance:

[0074] Aspect 1 provides an aqueous composition comprising:

a starting material beta-glucan, and

an enzyme.

[0075] Aspect 2 provides the composition of Aspect 1, wherein a manufacturer's solution including the enzyme is about 0.001 wt% to about 10 wt% of the composition.

[0076] Aspect 3 provides the composition of any one of Aspects 1-2, wherein a manufacturer's solution including the enzyme is 0.2 wt% to about 0.25 wt% of the composition.

[0077] Aspect 4 provides the composition of any one of Aspects 1-3, wherein a manufacturer's solution including the enzyme is present in the composition in an amount that is about 0.1 to about 100 times of the amount of the starting material beta-glucan present in the composition, by weight.

[0078] Aspect 5 provides the composition of any one of Aspects 1-4, wherein a manufacturer's solution including the enzyme is present in the composition in an amount that is about 2 to about 2.5 times of the amount of the starting material beta-glucan present in the composition, by weight.

[0079] Aspect 6 provides the composition of any one of Aspects 1-5, wherein the enzyme is reactive with the beta-glucan to form an enzyme-treated beta-glucan that is different than the starting material beta-glucan. [0080] Aspect 7 provides the composition of any one of Aspects 1-6, wherein the enzyme is Aspergillus oryzae protease, Subtilisin A, Proteinase K, or a combination thereof.

[0081] Aspect 8 provides the composition of any one of Aspects 1-7, wherein the starting material beta-glucan is about 0.001 wt% to about 50 wt% of the composition.

[0082] Aspect 9 provides the composition of any one of Aspects 1-8, wherein the starting material beta-glucan is about 0.05 wt% to about 0.15 wt% of the composition.

[0083] Aspect 10 provides the composition of any one of Aspects 1-9, wherein the starting material beta-glucan is an isolated beta-glucan.

[0084] Aspect 11 provides the composition of any one of Aspects 1-10, wherein the starting material beta-glucan is homogeneously distributed in the composition.

[0085] Aspect 12 provides the composition of any one of Aspects 1-11, wherein the starting material beta-glucan is dissolved in the composition.

[0086] Aspect 13 provides the composition of any one of Aspects 1-12, wherein the starting material beta-glucan is a 1,3 beta-glucan.

[0087] Aspect 14 provides the composition of any one of Aspects 1-13, wherein the starting material beta-glucan is a 1,3-1,6 beta-D-glucan.

[0088] Aspect 15 provides the composition of any one of Aspects 1-14, wherein the starting material beta-glucan is a 1,3-1,4 beta-D-glucan.

[0089] Aspect 16 provides the composition of any one of Aspects 1-15, wherein the starting material beta-glucan is scleroglucan.

[0090] Aspect 17 provides the composition of any one of Aspects 1-16, wherein the starting material beta-glucan is schizophyllan.

[0091] Aspect 18 provides the composition of any one of Aspects 1-17, wherein water is

50 wt% to about 99.999 wt% of the composition.

[0092] Aspect 19 provides the composition of any one of Aspects 1-18, wherein the water is 99.5 wt% to about 99.9 wt% of the composition.

[0093] Aspect 20 provides the composition of any one of Aspects 1-19, wherein the water is fresh water, salt water, brine, produced water, flowback water, brackish water, sea water, synthetic sea water, or a combination thereof.

[0094] Aspect 21 provides the composition of any one of Aspects 1-20, wherein the water has a total dissolved solids level of about 0 ppm to about 300,000 ppm. [0095] Aspect 22 provides the composition of any one of Aspects 1-21, wherein the water has a total dissolved solids level of about 800 ppm to about 1,000 ppm.

[0096] Aspect 23 provides the composition of any one of Aspects 1-22, wherein the water comprises NaCl at concentration of 0 ppm to about 300,000 ppm.

[0097] Aspect 24 provides the composition of any one of Aspects 1-23, wherein the water comprises NaCl at concentration of 800 ppm to about 1,000 ppm.

[0098] Aspect 25 provides an aqueous salt water composition comprising:

a starting material beta-glucan that is scleroglucan; and

an enzyme that is Aspergillus oryzae protease, Subtilisin A, Proteinase K, or a combination thereof.

[0099] Aspect 26 provides an enzyme-treated beta-glucan that is a reaction product of the enzyme and the starting material beta-glucan in the aqueous composition of any one of Aspects 1-25.

[00100] Aspect 27 provides the enzyme-treated beta-glucan of Aspect 26, wherein the enzyme-treated beta-glucan is in a solution that is generated from reaction of the composition of any one of Aspects 1-25 and that is free of purification.

[00101] Aspect 28 provides the enzyme-treated beta-glucan of any one of Aspects 26-27, wherein the enzyme-treated beta-glucan is purified from an unpurified solution that is generated from reaction of the composition any one of Aspects 1-25.

[00102] Aspect 29 provides the enzyme-treated beta-glucan of any one of Aspects 26-28, wherein an aqueous solution of the enzyme-treated beta-glucan has different rheological characteristics as compared to an aqueous solution of the starting material beta-glucan at the same concentration and under the same conditions.

[00103] Aspect 30 provides the enzyme-treated beta-glucan of any one of Aspects 26-29, wherein an aqueous solution of the enzyme-treated beta-glucan has reduced elasticity as compared to an aqueous solution of the starting material beta-glucan at the same concentration and under the same conditions.

[00104] Aspect 31 provides the enzyme-treated beta-glucan of any one of Aspects 26-30, wherein an aqueous solution of the enzyme-treated beta-glucan has a smaller pressure drop when pumped through a constriction as compared to an aqueous solution of the starting material beta- glucan at the same concentration and under the same conditions. [00105] Aspect 32 provides the enzyme-treated beta-glucan of any one of Aspects 26-31, wherein the enzyme-treated beta-glucan has a different particle size distribution as compared to the starting material beta-glucan under the same conditions.

[00106] Aspect 33 provides the enzyme-treated beta-glucan of any one of Aspects 26-32, wherein the enzyme-treated beta-glucan has a smaller volume mean particle size as compared to the starting material beta-glucan under the same conditions.

[00107] Aspect 34 provides the enzyme-treated beta-glucan of any one of Aspects 26-33, wherein the enzyme-treated beta-glucan has a smaller D10, D50, D90, or combination thereof, as compared to the starting material beta-glucan under the same conditions.

[00108] Aspect 35 provides the enzyme-treated beta-glucan of any one of Aspects 26-34, wherein the enzyme-treated beta-glucan has a volume mean particle size of about 1 micron to about 150 microns.

[00109] Aspect 36 provides the enzyme-treated beta-glucan of any one of Aspects 26-35, wherein the enzyme-treated beta-glucan has a volume mean particle size of about 30 micron to about 100 microns.

[00110] Aspect 37 provides the enzyme-treated beta-glucan of any one of Aspects 26-36, wherein an aqueous solution of the enzyme-treated beta-glucan has a different Filterability Ratio as compared to the Filterability Ratio of an aqueous solution of the starting material beta-glucan under the same conditions.

[00111] Aspect 38 provides the enzyme-treated beta-glucan of any one of Aspects 26-37, wherein an aqueous solution of the enzyme-treated beta-glucan has a lower Filterability Ratio as compared to the Filterability Ratio of an aqueous solution of the starting material beta-glucan under the same conditions.

[00112] Aspect 39 provides the enzyme-treated beta-glucan of any one of Aspects 26-38, wherein an aqueous solution of the enzyme-treated beta-glucan has a Filterability Ratio of about 0.9 to about 20.

[00113] Aspect 40 provides the enzyme-treated beta-glucan of any one of Aspects 26-39, wherein an aqueous solution of the enzyme-treated beta-glucan has a Filterability Ratio of about 1 to about 2. [00114] Aspect 41 provides the enzyme-treated beta-glucan of any one of Aspects 26-40, wherein an aqueous solution of the enzyme-treated beta-glucan has a Filterability Ratio of about 1 to about 1.5.

[00115] Aspect 42 provides a method of making the enzyme-treated beta-glucan of any one of Aspects 26-41, comprising reacting the composition of any one of Aspects 1-25.

[00116] Aspect 43 provides the method of Aspect 42, further comprising forming the composition of any one of Aspects 1-25.

[00117] Aspect 44 provides the method of Aspect 43, wherein forming the composition of any one of Aspects 1-25 comprises shearing a composition comprising the starting material beta- glucan for at least about 0.01 s at a shear rate of about 40,000 s ^"1 to about 300,000 s ^"1 , and adding the enzyme.

[00118] Aspect 45 provides the method of any one of Aspects 43-44, wherein forming the composition of any one of Aspects 1-25 comprises shearing a composition comprising the starting material beta-glucan for about 0.06 s to about 6 s at a shear rate of about 260,000 s ^"1 , and adding the enzyme.

[00119] Aspect 46 provides the method of any one of Aspects 42-45, wherein the method is a method of treating the starting material beta-glucan to improve its properties for treatment of a subterranean formation.

[00120] Aspect 47 provides the method of Aspect 46, wherein the improved properties comprise rheology, particle size, Filterability Ratio, or a combination thereof.

[00121] Aspect 48 provides a method of treating a starting material beta-glucan to improve its properties for treatment of a subterranean formation, the method comprising:

reacting a starting material beta-glucan with an enzyme to provide an enzyme-treated beta-glucan that is a reaction product of the enzyme and the starting material beta-glucan.

[00122] Aspect 49 provides a method of treating a subterranean formation with the composition of any one of Aspects 1-25, the method comprising:

placing the composition of any one of Aspects 1-25 in the subterranean formation.

[00123] Aspect 50 provides a method of treating a subterranean formation with the enzyme-treated beta-glucan of any one of Aspects 26-41, the method comprising:

placing the enzyme-treated beta-glucan in the subterranean formation. [00124] Aspect 51 provides the method of Aspect 50, comprising performing a hydraulic fracturing operating in the subterranean formation using a liquid comprising the enzyme-treated beta-glucan.

[00125] Aspect 52 provides the method of any one of Aspects 50-51, comprising performing an enhanced oil recovery procedure in the subterranean formation using a liquid comprising the enzyme-treated beta-glucan.

[00126] Aspect 53 provides the method of Aspect 52, wherein the enhanced oil recovery procedure comprises polymer flooding.

[00127] Aspect 54 provides the method of any one of Aspects 52-53, wherein the liquid comprising the enzyme-treated beta-glucan in the subterranean formation sweeps petroleum in the subterranean formation toward a well.

[00128] Aspect 55 provides the method of Aspect 54, further comprising removing the petroleum from the well.

[00129] Aspect 56 provides a use of the enzyme-treated beta-glucan of any one of Aspects

26-41 for treatment of a subterranean formation.

[00130] Aspect 57 provides the composition, enzyme-treated beta-glucan, method, or use of any one or any combination of Aspects 1-56 optionally configured such that all elements or options recited are available to use or select from.