Single blended cement system for use at wide ranges of density and temperatures
View Patent ↗A method of cementing a wellbore penetrating a subterranean formation comprises blending a base cement slurry with one or more liquid additives to provide a cementing composition, the base cement slurry comprising a liquid carrier, a class G cement or a blend of class G and class C cements as defined by the American Petroleum Institute (API) Specification 10A standards (R2015), and silica fume, or fumed silica, or a combination of silica fume and fumed silica, the base cement slurry having a density of about 14 to about 16 ppg; and injecting the cementing composition into the wellbore. The single base cement slurry can be used globally to make cementing compositions having wide ranges of density and temperature stability.
1. A method of cementing a wellbore penetrating a subterranean formation, the method comprising:
blending a base cement slurry with one or more liquid additives to provide a cementing composition,
the base cement slurry comprising
a liquid carrier;
a class G cement or a combination of a class G and class C cements;
silica fume, or fumed silica, or a combination of silica fume and fumed silica,
the base cement slurry having a density of 14 to 16 ppg; and
injecting the cementing composition into the wellbore,
wherein the one or more of the liquid additives comprise a heavy weight liquid additive comprising (1) about 100 to about 200 wt % of cerium oxide; or about 300 to about 500 wt % of manganese oxide, (2) water; and (3) 0.5 to 2 wt % of a diutan gum, each by weight of the water in the heavy weight liquid additive, the heavy weight liquid additive having a density of about 20 to about 24 ppg.
2. The method of claim 1 , wherein the base cement slurry comprises about 1 to about 10 wt % of the fumed silica or silica fume or a combination of the fumed silica and silica fume, each based on the total weight of the base cement slurry.
3. The method of claim 2 , wherein the base cement slurry comprises water, class G cement, about 1 to about 10 wt % of kaolinite clay, and about 3 to 7 wt % of silica fume or fumed silica or a combination thereof, each based on the total weight of the base cement slurry.
4. The method of claim 2 , wherein the base cement slurry comprises water, a blend of class G and class C cements having a weight ratio of about 5:1 to about 3:1, and about 3 to 7 wt % of silica fume or fumed silica or a combination thereof, each based on the total weight of the base cement slurry.
5. The method of claim 1 , wherein the heavy weight liquid additive further comprises a dispersant.
6. The method of claim 1 , wherein the heavy weight liquid additive comprises about 100 to about 200 wt % of cerium oxide and about 0.5 to 2 wt % of the diutan gum, each by weight of the water in the heavy weight liquid additive.
7. The method of claim 1 , wherein the heavy weight liquid additive comprises about 300 to about 500 wt. % of manganese oxide and 0.5 to 2 wt % of the diutan gum, each by weight of the water in the heavy weight liquid additive.
8. The method of claim 1 , wherein the liquid additive further comprises a retarder, accelerator, fluid loss additive, foam preventer, or a buffering agent.
9. The method of claim 1 , wherein the base cement slurry is not directly blended with any solid additive.
10. The method of claim 1 , wherein the cementing composition has a density of about 11 to about 18 ppg.
11. The method of claim 1 , wherein the cementing composition has a temperature stability range of about 40° C. to about 350° C.
12. A method of cementing a wellbore penetrating a subterranean formation, the method comprising:
blending a base cement slurry with one or more liquid additives to provide a cementing composition,
the base cement slurry comprising
a liquid carrier;
a class G cement or a combination of a class G and class C cements;
silica fume, or fumed silica, or a combination of silica fume and fumed silica,
the base cement slurry having a density of 14 to 16 ppg; and
injecting the cementing composition into the wellbore;
wherein the one or more liquid additives comprise a light weight liquid additive comprising (1) about 30 to about 50 wt % of a glass sphere, (2) about 0.5 to about 2 wt % of a diutan gum, and (3) water by weight of the water in the light weight liquid additive, the liquid weight liquid additive having a density of 5 to 7.
13. The method of claim 12 , wherein the glass sphere is a borosilicate glass sphere.
14. A method of cementing a wellbore penetrating a subterranean formation, the method comprising:
blending a base cement slurry with one or more liquid additives to provide a cementing composition,
the base cement slurry comprising
a liquid carrier;
a class G cement or a combination of a class G and class C cements;
about 1 to about 10 wt % of kaolinite clay,
about 3 to 7 wt % of silica fume, or fumed silica, or a combination of silica fume and fumed silica,
the base cement slurry having a density of 14 to 16 ppg; and
injecting the cementing composition into the wellbore,
wherein the one or more liquid additives comprise a silica suspension liquid additive which comprises (1) 20 to 40 wt % of silica flour, (2) 20 to 40 wt % of silica sand, (3) a diutan gum, and (4) 20 to 40 wt % % water each based on the total weight of the silica suspension liquid additive.
15. The method of claim 14 , wherein the base cement slurry is free of silica sand and silica flour; and the base cement slurry is blended with the silica suspension liquid additive in an amount such that the cementing composition has a target cement performance in a high temperature well environment.