Preparation of guar suspension from guar splits
View Patent ↗A continuous process forms liquid or semi-solid suspensions of water-hydratable guar particles in a non-aqueous solvent directly from hydrated guar splits. In particular, guar splits are hydrated, compressed to form wet guar flakes, and then dried. The dried guar flakes are then combined with a non-aqueous carrier fluid. Finally, the guar and carrier fluid mixture is homogenized, and, if desired, the homogenized guar and carrier fluid mixture may be shear milled to further size-reduce the average particle size of the guar particle.
1. A continuous method for using hydrated guar splits to form liquid or semisolid suspensions of water-hydratable guar particles in a non-aqueous solvent, comprising:
a. hydrating guar splits;
b. compressing the hydrated guar splits to form wet guar flakes;
c. drying the wet guar flakes;
d. combining the dried guar flakes with a non-aqueous carrier fluid;
e. reducing particle size of the guar particles in the guar and non-aqueous carrier fluid mixture.
2. The method of claim 1 wherein the water-hydratable guar particles are carboxyalkyl guar, hydroxyalkyl guar, carboxyalkyl hydroxyalkyl guar, or combinations thereof.
3. The method of claim 1 further comprising the step of homogenizing the guar and non-aqueous carrier fluid mixture.
4. The method of claim 1 wherein the reduced size guar particles have an average particle size distribution range of about 20 to about 60 microns in diameter.
5. The method of claim 1 wherein the direct processing of hydrated guar splits to form liquid suspensions of guar particles in a non-aqueous solvent is continuous and automated.
6. The method of claim 5 wherein the continuous elements may additionally comprise:
a. side-stream batch additive processes;
b. re-circulation processes; and
c. material extraction and recovery processes.
7. The method of claim 6 wherein the continuous elements comprise the addition of suspension aids to non-aqueous solvents.
8. The method of claim 7 wherein the suspension aids may be selected from the group comprising organophilic clays, amorphous silicas, emulsifiers, suspending polymers, and mixtures thereof.
9. The method of claim 5 wherein the continuous elements comprise the recirculation of non-aqueous solvents until the prescribed quantity of guar particles is attained.
10. The method of claim 9 wherein the quantity of guar particles comprises from about 20 percent to about 80 percent by weight of the total weight of the guar slurry.
11. The method of claim 9 wherein the non-aqueous solvents are selected from the list of hydrocarbon oils, medicinal oils, vegetable oils, polyols, glycols, polyethylene glycols, alcohols, and mixtures thereof.
12. The method of claim 1 wherein the hydrated guar splits are compressed by machine processing through a burr mill, an extruder, a roller mill, or a combination of compressing devices.
13. The method of claim 12 wherein the hydrated guar splits are compressed by a roller mill.
14. The method of claim 13 wherein the hydrated guar splits are sequentially compressed two or more times by matched diameter rollers set at rotation ratios of from about 5:1 to about 25:1.
15. The method of claim 1 wherein the hydrated guar splits are dewatered by flash-drying.
16. The method of claim 1 wherein the hydrated guar splits are dewatered during transit through a heated auger.
17. The method of claim 16 wherein the heated auger comprises a bank of heated augers set in parallel.
18. The method of claim 1 wherein the de-watered guar splits are combined with the non-aqueous solvent by means of a homogenizing mixer.
19. A continuous method for using hydrated guar splits to form liquid or semi-solid suspensions of water-hydratable guar particles in a non-aqueous solvent, comprising:
a. hydrating guar splits;
b. compressing the hydrated guar splits to form wet guar flakes;
c. drying the wet guar flakes;
d. combining the dried guar flakes with a non-aqueous carrier fluid;
e. homogenizing the guar and non-aqueous carrier fluid mixture; and
f. shear milling the homogenized guar and non-aqueous carrier fluid mixture to further size-reduce the average particle size of the guar particle.
20. The method of claim 19 wherein the hydrated guar splits are carboxyalkyl guar splits, hydroxyalkyl guar splits, carboxyalkyl hydroxyalkyl guar splits, or mixtures thereof.
21. A continuous method for using hydrated guar splits to form liquid or semi-solid suspensions of water-hydratable guar particles in a non-aqueous solvent, comprising:
a. hydrating guar splits;
b. compressing the hydrated guar splits to form wet guar flakes;
c. drying the wet guar flakes;
d. combining the dried guar flakes with a non-aqueous carrier fluid and a boron compound;
e. homogenizing the guar, boron compound, and non-aqueous carrier fluid mixture; and
f. shear milling the homogenized guar, boron compound, and non-aqueous carrier fluid mixture to further size-reduce the average particle size of the guar particle.
22. The continuous method of claim 21 wherein the boron compound is boric acid or anhydrous borax, or mixtures thereof.
23. A method of forming a fracturing fluid, comprising:
a. hydrating guar splits;
b. compressing the hydrated guar splits to form wet guar flakes;
c. drying the wet guar flakes;
d. combining-the dried guar flakes with a non-aqueous carrier fluid;
e. reducing particle size of the guar particles in the guar and non-aqueous carrier fluid mixture, thus forming a suspension of the guar particles;
f. adding a quantity of the guar suspension to water to form a guar solution; and
g. pumping the guar solution via a wellbore into a subterranean formation at a pressure sufficient to induce a fracture in the formation rock.
24. The method of claim 23 wherein the guar particles are selected from the group of carboxyalkyl guar, hydroxyalkyl guar, carboxyalkyl hydroxyalkyl guar, and mixtures thereof.
25. The method of claim 23 wherein the guar particles of the guar suspension comprises from 20 percent to about 80 percent by weight of the total weight of the guar suspension, and wherein the guar in water solution contains from about 0.02 percent to about 2 percent by weight guar.