CELLULOSE NANOFIBERS IN EXTENDED CEMENT SYSTEMS
Methods herein may include injecting a cement slurry having an aqueous base fluid, a cement, and a plurality of cellulose nanofibers dispersed in the aqueous base fluid. The plurality of cellulose nanofibers may be present in the slurry in an amount effective to provide a slurry density of not higher than 15 lb/gal.
1 . A cement slurry for treating a wellbore, comprising:
an aqueous base fluid;
a cement; and
a plurality of cellulose nanofibers dispersed in the aqueous base fluid; and
wherein the plurality of cellulose nanofibers is present in the slurry in an amount effective to provide a slurry density of not higher than 15 lb/gal,
an anti-foaming agent.
2 . The slurry of claim 1 , wherein the density of the cement slurry ranges from about 6 to about 15 lb/gal.
3 . The slurry of claim 1 , wherein the plurality of cellulose nanofibers further increases a slurry yield by 1 to 3 feet cubed per sack depending on the density of the slurry.
4 . The slurry of claim 1 , wherein the plurality of cellulose nanofibers is present in the cement slurry in a concentration ranging from about 0.03 to about 6% by weight of a blend, where the blend refers to all solid materials in the slurry including cement.
5 . The slurry of claim 1 , wherein the cellulose nanofibers are selected from the group of cellulose nanofibrils and cellulose nanocrystals.
6 . The slurry of claim 5 , wherein the cellulose nanofibers are cellulose nanofibrils present in the slurry in a concentration ranging from about 0.03 to about 2.5% by weight of a blend, where the blend refers to all solid materials in the slurry including cement.
7 . The slurry of claim 5 , wherein the cellulose nanofibers are cellulose nanocrystals present in the slurry in a concentration ranging from about 0.2 to about 6% by weight of a blend, where the blend refers to all solid materials in the slurry including cement.
8 . The slurry of claim 1 , wherein the cellulose nanofibers have a length ranging from about 100 nm to about 3 mm.
9 . The slurry of claim 1 , wherein the cellulose nanofibers have a diameter ranging from about 4 nm to about 20 μm.
10 . The slurry of claim 1 , further comprising at least an additive selected from the group of fly ash, silica, cenospheres, a dispersant, a fluid loss control additive or a combination thereof.
11 . The slurry of claim 1 , further comprising gas bubbles and a foaming agent.
12 . A method for treating a subterranean formation penetrated by a wellbore, the method comprising:
injecting a cement slurry into the wellbore, the slurry comprising:
an aqueous base fluid;
a cement; and
a plurality of cellulose nanofibers dispersed in the aqueous base fluid;
wherein the plurality of cellulose nanofibers is present in the slurry in an amount effective to provide a slurry density of not higher than 15 lb/gal; and
allowing the cement slurry to set.
13 . The method of claim 12 , further comprising: performing a downhole operation.
14 . The method of claim 12 , wherein the injecting comprises pumping the cement slurry through the wellbore and into an annulus formed between the wellbore and a casing.
15 . The method of claim 12 , wherein the density of the cement slurry ranges from about 6 to about 15 lb/gal.
16 . The method of claim 12 , wherein the plurality of cellulose nanofibers further increases a slurry yield by 1 to 3 feet cubed per sack depending on the density of the slurry.
17 . The method of claim 12 , wherein the plurality of cellulose nanofibers is present in the cement slurry in a concentration ranging from about 0.03 to about 6% by weight of the blend.
18 . The method of claim 12 , wherein the cellulose nanofibers are selected from the group of cellulose nanofibrils and cellulose nanocrystals.
19 . The method of claim 12 , wherein the cellulose nanofibers have a length ranging from about 100 nm to about 3 mm.
20 . The method of claim 12 , wherein the cellulose nanofibers have a diameter ranging from about 4 nm to about 20 μm.