Suspension of borates in non-aqueous solvents and use thereof

1. A non-aqueous suspension comprising:

(a) boron-containing particulates;

(b) low molecular weight polyalkylene glycol; and

(c) a suspension stabilizer comprising an hydrogenated castor oil or wax;

wherein the boron-containing particulates are selected from the group consisting of alkaline metal borates, boric acid, and mixtures thereof.

2. The suspension of claim 1 wherein boron-containing particulates comprise between about 0.1 weight percent to about 60 weight percent of the total suspension weight.

3. The suspension of claim 1 wherein said boron-containing particulates have an average particle size of about 0.1 microns to about 600 microns.

4. The suspension of claim 1 wherein said boron-containing particulates have an average particle size of about 1 micron to about 300 microns.

5. The suspension of claim 1 wherein said boron-containing particulates have an average particle size of about 5 microns to about 200 microns.

6. The suspension of claim 1 wherein the boron content (as percent B) of the non-aqueous suspension comprise between about 0.01 weight percent to about 45 weight percent of the total suspension weight.

7. The suspension of claim 1 wherein said low molecular weight polyalkylene glycol comprises between about 35 weight percent to about 99.8 weight percent of the total suspension weight.

8. The suspension of claim 1 wherein said low molecular weight polyalkylene glycol is selected from the group consisting of polyethylene glycol, polypropylene glycol, and mixtures thereof.

9. The suspension of claim 1 wherein said low molecular weight polyalkylene glycol has a molecular weight less than about 1000.

10. The suspension of claim 1 wherein said low molecular weight polyalkylene glycol has a molecular weight between about 100 and about 600.

11. The suspension of claim 1 wherein said low molecular weight polyalkylene glycol has a molecular weight between about 200 and about 500.

12. The suspension of claim 1 wherein the hydrogenated castor oil or wax comprises between about 0.1 weight percent to about 5.0 weight percent of the total suspension weight.

13. The suspension of claim 1 wherein the hydrogenated castor oil or wax comprises between about 0.3 weight percent to about 3.0 weight percent of the total suspension weight.

14. The suspension according to claim 1 wherein the amount of hydrogenated castor oil or wax comprises between about 0.5 weight percent to about 2.0 weight percent of the suspension.

15. The suspension of claim 1 further comprising one or more additives selected from the group consisting of salts, pH buffers, surfactants, emulsifiers, demulsifiers, foaming agents, antifoaming agents, water miscible co-solvents, preservatives, clay stabilizers, corrosion inhibitors, scale removers, paraffin solvents, iron chelants, hardness ion chelants, antioxidants, biocidal agents, gel preservatives and gel breakers.

16. A non-aqueous suspension comprising:

(a) boron-containing particulates;

(b) low molecular weight polyalkylene glycol;

(c) a suspension stabilizer comprising an hydrogenated castor oil or wax; and

(d) a thickener for the polyalkylene glycol;

wherein the boron-containing particulates are selected from the group consisting of alkaline metal borates, boric acid, and mixtures thereof.

17. The suspension of claim 16 wherein boron-containing particulates comprise between about 0.1 weight percent to about 60 weight percent of the total suspension weight.

18. The suspension of claim 16 wherein said boron-containing particulates have an average particle size of about 0.1 microns to about 600 microns.

19. The suspension of claim 16 wherein said boron-containing particulates have an average particle size of about 1 micron to about 300 microns.

20. The suspension of claim 16 wherein said boron-containing have an average particle size of about 5 microns to about 200 microns.

21. The suspension of claim 16 wherein said boron content (as percent B) of the non-aqueous suspension comprises between about 0.01 weight percent to about 20 weight percent.

22. The suspension of claim 16 wherein said low molecular polyalkylene glycol comprises between about 35 weight percent to about 99.8 weight percent of the total suspension weight.

23. The suspension of claim 16 wherein said low molecular polyalkylene glycol is selected from the group consisting of polyethylene glycol, polypropylene glycol, and mixtures thereof.

24. The suspension of claim 16 wherein said low molecular weight polyalkylene glycol has a molecular weight less than about 1000.

25. The suspension of claim 16 wherein said low molecular weight polyalkylene glycol has a molecular weight between about 100 and about 600.

26. The suspension of claim 16 wherein said low molecular weight polyalkylene glycol has a molecular weight between about 200 and about 500.

27. The suspension of claim 16 wherein the hydrogenated castor oil or wax stabilizer comprises between about 0.1 weight percent to about 5.0 weight percent of the total suspension weight.

28. The suspension of claim 16 wherein the hydrogenated castor oil or wax stabilizer comprises between about 0.3 weight percent to about 3.0 weight percent of the total suspension weight.

29. The suspension according to claim 16 wherein the amount of hydrogenated castor oil or wax comprises between about 0.5 weight percent to about 2.0 weight percent of the suspension.

30. The suspension of claim 16 wherein the polyalkylene glycol thickener is selected from the group consisting of partially neutralized polyacrylic acid, hydroxypropyl cellulose, highly substituted hydroxypropyl guar, hydrated thickening silica, and mixtures thereof.

31. The suspension of claim 16 further comprising one or more additives selected from the group consisting of salts, pH buffers, surfactants, emulsifiers, demulsifiers, foaming agents, antifoaming agents, water miscible co-solvents, clay stabilizers, preservatives, corrosion inhibitors, scale removers, paraffin solvents, iron chelants, hardness ion chelants, antioxidants, biocidal agents, gel preservatives and gel breakers.

32. A crosslinked hydraulic fracturing fluid comprising:

(a) a water-soluble polymer; and

(b) a non-aqueous boron crosslinker suspension comprising:

(i) boron-containing particulates;

(ii) a low molecular weight polyalkylene glycol, and

(iii) a suspension stabilizer comprising a hydrogenated castor oil or wax;

wherein the polymer is crosslinked with the non-aqueous boron crosslinker.

33. The crosslinked fracturing fluid of claim 32 wherein the boron-containing particulates are selected from the group consisting of alkaline metal borates, boric acid, and mixtures thereof.

34. The crosslinked fracturing fluid of claim 32 wherein the amount of the boron-containing particulates is between about 0.1 weight percent and about 60 weight percent of the total suspension weight.

35. The crosslinked fracturing fluid of claim 32 wherein the amount of boron content (as percent B) of the non-aqueous suspension is between about 0.01 weight percent and about 20 weight percent of the total suspension weight.

36. The crosslinked fracturing fluid of claim 32 wherein the low molecular weight polyalkylene glycol is selected from the group consisting of polyethylene glycol, polypropylene glycol, and mixtures thereof.

37. The crosslinked fracturing fluid of claim 32 wherein the suspension stabilizer is a hydrogenated castor oil or wax.

38. The crosslinked fracturing fluid of claim 32 wherein the boron-containing particulates have an average particle size of about 0.1 microns to about 600 microns.

39. The crosslinked fracturing fluid of claim 32 wherein the amount of the low molecular weight polyalkylene glycol is between about 35 weight percent and about 99.8 weight percent of the total suspension weight.

40. The crosslinked fracturing fluid of claim 32 wherein the amount of suspension stabilizer is between about 0.1 weight percent to about 5 weight percent of the total suspension weight.

41. The crosslinked fracturing fluid of claim 32 wherein the water-soluble polymer contained in the water-soluble polymer solution is selected from the group of guar, hydroxyalkyl guar, carboxyalkyl guar, carboxyalkyl hydroxyalkyl guar, and mixtures thereof.

42. The crosslinked fracturing fluid of claim 32 wherein the amount of water-soluble polymer is between about 0.12 weight percent and 2.0 weight percent of total fracturing fluid weight.

43. The crosslinked fracturing fluid of claim 32 wherein the pH of the crosslinked fluid is greater than about pH 8.5.

44. A crosslinked hydraulic fracturing fluid comprising:

(a) a water-soluble polymer;

(b) a non-aqueous boron crosslinker suspension comprising:

(i) boron-containing particulates;

(ii) a low molecular weight polyalkylene glycol, and

(iii) a suspension stabilizer comprising a hydrogenated castor oil or wax; and

(c) water;

wherein the polymer is crosslinked with the non-aqueous boron crosslinker.

45. The crosslinked hydraulic fracturing fluid of claim 44 wherein the crosslinking reaction rate is accelerated by the addition of water.

46. The crosslinked hydraulic fracturing fluid of claim 45 wherein the amount of water is between about 10 weight percent and about 25 weight percent of the total weight of the crosslinker suspension.

47. The crosslinked hydraulic fracturing fluid of claim 45 wherein the fracturing fluid temperature is less than about 75° F. and wherein the amount of water is between about 10 weight percent and about 25 weight percent of the total weight of the crosslinker suspension.

48. A crosslinked hydraulic fracturing fluid comprising:

(a) a water-soluble polymer;

(b) a non-aqueous boron crosslinker suspension comprising:

(i) boron-containing particulates;

(ii) a low molecular weight polyalkylene glycol,

(iii) a suspension stabilizer comprising a hydrogenated castor oil or wax; and

(iv) a thickener for the polyalkylene glycol; and

(c) water;

wherein the polymer is crosslinked with the non-aqueous boron crosslinker.

49. A non-aqueous boron crosslinker suspension comprising:

(a) between about 30 weight percent and about 50 weight percent solid particles of an alkaline metal borate, boric acid, or mixtures thereof;

(b) between about 48 weight percent and about 70 weight percent low molecular weight polyethylene glycol; and

(c) between about 0.5 weight percent and about 2 weight percent hydrogenated castor wax.

50. The boron crosslinker suspension of claim 49 wherein the low molecular weight polyethylene glycol has an average molecular weight ranging from about 100 to about 500.

51. The boron crosslinker suspension of claim 49 wherein the low molecular weight polyethylene glycol has an average molecular weight of about 200.

52. A method of crosslinking one or more water soluble polymers comprising:

adding to a hydrated or colloidal dispersion of one or more water soluble polymers an effective crosslinking amount of a non-aqueous boron crosslinker comprising:

(a) boron-containing particulates;

(b) low molecular weight polyalkylene glycol; and

(c) a suspension stabilizer comprising an hydrogenated castor oil or wax.

53. The method of claim 52 wherein the water soluble polymers are selected from the group of polyvinyl alcohols, starches, derivatized starches, guar, derivatized guars, and locust bean gum.

54. The method of claim 53 wherein the derivatized guar is selected from the group of hydroxyalkyl guar, carboxyalkyl guar, carboxyalkyl hydroxyalkyl guar, and mixtures thereof.

55. A method of crosslinking one or more water soluble polymers comprising:

adding to a hydrated or colloidal dispersion of one or more water soluble polymers an effective crosslinking amount of a non-aqueous boron crosslinker comprising:

(a) boron-containing particulates;

(b) low molecular weight polyalkylene glycol;

(c) a suspension stabilizer comprising an hydrogenated castor oil or wax; and

(d) a thickener for the polyalkylene glycol.

56. The method of claim 55 wherein the water soluble polymers are selected from the group of polyvinyl alcohols, starches, derivatized starches, guar, derivatized guars, and locust bean gum.

57. The method of claim 56 wherein the derivatized guar is selected from the group of hydroxyalkyl guar, carboxyalkyl guar, carboxyalkyl hydroxyalkyl guar, and mixtures thereof.

58. The method of claim 55 wherein the thickener for the polyalkylene glycol is selected from the group consisting of partially neutralized polyacrylic acid, hydroxypropyl cellulose, highly substituted hydroxypropyl guar, fumed silica, hydrophobic silica, and mixtures thereof.

59. A method of fracturing a subterranean formation comprising:

(1) forming a hydraulic fracturing fluid comprising:

(a) water

(b) a water soluble polymer, and

(c) a non-aqueous boron crosslinker suspension comprising:

(i) boron-containing particulates;

(ii) low molecular weight polyalkylene glycol; and

(iii) a suspension stabilizer comprising an hydrogenated castor oil or wax, and

(2) pumping said fracturing fluid via tubing or casing into a subterranean formation with sufficient force to initiate a fracture.

60. A method of fracturing a subterranean formation comprising:

(1) forming a hydraulic fracturing fluid comprising:

(a) water;

(b) a water soluble polymer, and

(c) a boron crosslinker suspension comprising:

(i) boron-containing particulates;

(ii) low molecular weight polyalkylene glycol;

(iii) a suspension stabilizer comprising an hydrogenated castor oil or wax; and

(iv) water; and

(2) pumping said fracturing fluid via tubing or casing into a subterranean formation with sufficient force to initiate a fracture.

61. A method of fracturing a subterranean formation comprising:

(1) forming a hydraulic fracturing fluid comprising:

(a) water

(b) a water soluble polymer, and

(c) a boron crosslinker suspension comprising:

(i) boron-containing particulates;

(ii) low molecular weight polyalkylene glycol;

(iii) a suspension stabilizer comprising an hydrogenated castor oil or wax;

(iv) a thickener for the polyalkylene glycol; and

(v) water; and

(2) pumping said fracturing fluid via tubing or casing into a subterranean formation with sufficient force to initiate a fracture.

62. The method of claim 59 wherein the fracturing fluid further comprises an alkaline compound sufficient to raise the pH of the fracturing fluid to about 8.5 or greater.

63. The method of claim 60 wherein the fracturing fluid further comprises an alkaline compound sufficient to raise the pH of the fracturing fluid to about 8.5 or greater.

64. The method of claim 61 wherein the fracturing fluid further comprises an alkaline compound sufficient to raise the pH of the fracturing fluid to about 8.5 or greater.

65. The non-aqueous suspension of claim 1 wherein the suspension has a PMCC flashpoint greater than about 140° F., has hexane extractable oil and grease of less than about 30 ppm, and has a boron content greater than about 1 weight percent.

66. The non-aqueous suspension of claim 16 wherein the suspension has a PMCC flashpoint greater than about 140° F., has hexane extractable oil and grease of less than about 30 ppm, and has a boron content greater than about 1 weight percent.

67. The boron crosslinker suspension of claim 49 wherein the suspension has a PMCC flashpoint greater than about 140° F., and has hexane extractable oil and grease of less than about 30 ppm.

68. The method of claim 52 wherein the boron crosslinker suspension has a PMCC flashpoint greater than about 140° F., has hexane extractable oil and grease of less than about 30 ppm, and has a boron content greater than about 1 weight percent.

69. The method of claim 55 wherein the boron crosslinker suspension has a PMCC flashpoint greater than about 140° F., has hexane extractable oil and grease of less than about 30 ppm, and has a boron content greater than about 1 weight percent.

70. The method of claim 54 wherein the hydroxyalkyl guar is hydroxypropyl guar, the carboxyalkyl guar is carboxymethyl guar, and carboxyalkyl hydroxyalkyl guar is carboxymethyl hydroxypropyl guar.

71. The method of claim 57 wherein the hydroxyalkyl guar is hydroxypropyl guar, the carboxyalkyl guar is carboxymethyl guar, and carboxyalkyl hydroxyalkyl guar is carboxymethyl hydroxypropyl guar.