Fluid loss control additive

Patent metadata

Field	Value
Publication number	US-12134732-B2
Application number	US-202117643252-A
Country	US
Kind code	B2
Filing date	Dec 8, 2021
Priority date	Dec 8, 2021
Publication date	Nov 5, 2024
Grant date	Nov 5, 2024

Abstract

Fluid loss control additives for a cement slurry are provided. An exemplary fluid loss control additive includes a copolymer containing 2-acrylamido-2-methylpropane sulfonic acid monomer units and acryloylmorpholine monomer units, and a graft copolymer. The graft copolymer contains a humate and, grafted onto the humate, a side-chain polymer containing at least one of acrylamide monomer units, acryloylmorpholine monomer units, acrylic acid monomer units, and 2-acrylamido-2-methylpropane sulfonic acid monomer units.

First claim

What is claimed is:

1. A fluid loss control additive comprising:
a copolymer comprising 2-acrylamido-2-methylpropane sulfonic acid monomer units and acryloylmorpholine monomer units; and
a graft copolymer comprising a humate and, grafted onto the humate, a side-chain polymer comprising:
acrylamide monomer units;
acryloylmorpholine monomer units;
acrylic acid monomer units; and
2-acrylamido-2-methylpropane sulfonic acid monomer units;

wherein:
the acrylamide monomer units comprise about 10% to about 40% of a total number of monomer units of the side-chain polymer;
the acryloylmorpholine monomer units comprise about 5% to about 35% of a total number of monomer units of the side-chain polymer;
the acrylic acid monomer units comprise about 10% to about 40% of a total number of monomer units of the side-chain polymer; and
the 2-acrylamido-2-methylpropane sulfonic acid monomer units comprise about 20% to about 75% of a total number of monomer units of the side-chain polymer.

2. The fluid loss control additive of claim 1 , wherein:
the 2-acrylamido-2-methylpropane sulfonic acid monomer units comprise about 10% to about 90% of a total number of monomer units of the copolymer; and
the acryloylmorpholine monomer units comprise about 10% to about 90% of a total number of monomer units of the copolymer.

3. The fluid loss control additive of claim 1 , wherein:
the 2-acrylamido-2-methylpropane sulfonic acid monomer units comprise about 40% to about 80% of a total number of monomer units of the copolymer; and
the acryloylmorpholine monomer units comprise about 20% to about 60% of a total number of monomer units of the copolymer.

4. The fluid loss control additive of claim 1 , wherein the humate comprises about 1 wt % to about 20 wt % of the graft copolymer.

5. The fluid loss control additive of claim 1 , wherein the copolymer and the graft copolymer are present in the additive in a weight ratio of about 100:1 to about 1:100.

6. The fluid loss control additive of claim 1 , wherein the copolymer and the graft copolymer are present in the additive in a weight ratio of about 4:1 to about 1:4.

7. The fluid loss control additive of claim 1 , comprising:
about 20 wt % to about 80 wt % of the copolymer; and
about 20 wt % to about 80 wt % of the graft copolymer.

8. The fluid loss control additive of claim 1 , wherein the copolymer and the graft copolymer are present in a combined amount of at least about 80 wt % of the additive.

9. A slurry, comprising:
water;
a cement;
a copolymer of 2-acrylamido-2-methylpropane sulfonic acid monomer units and acryloylmorpholine monomer units; and
a graft copolymer comprising a humate and, grafted onto the humate, a side-chain polymer comprising:
acrylamide monomer units;
acryloylmorpholine monomer units;
acrylic acid monomer units; and
2-acrylamido-2-methylpropane sulfonic acid monomer units;

wherein:
the acrylamide monomer units comprise about 10% to about 40% of a total number of monomer units of the side-chain polymer;
the acryloylmorpholine monomer units comprise about 5% to about 35% of a total number of monomer units of the side-chain polymer;
the acrylic acid monomer units comprise about 10% to about 40% of a total number of monomer units of the side-chain polymer; and
the 2-acrylamido-2-methylpropane sulfonic acid monomer units comprise about 20% to about 75% of a total number of monomer units of the side-chain polymer.

10. The slurry of claim 9 , wherein the cement comprises a Portland cement.

11. The slurry of claim 9 , wherein the cement comprises a Portland cement and a slag cement.

12. The slurry of claim 9 , wherein:
a weight of the copolymer present in the slurry is about 0.05% to about 10% of a weight of the cement present in the slurry; and
a weight of the graft copolymer present in the slurry is about 0.05% to about 10% of the weight of the cement present in the slurry.

13. The slurry of claim 9 , wherein:
a weight of the copolymer present in the slurry is about 0.1% to about 5% of a weight of the cement present in the slurry; and
a weight of the graft copolymer present in the slurry is about 0.1% to about 5% of the weight of the cement present in the slurry.

14. The slurry of claim 9 , further comprising an American Petroleum Institute (API) Class G cement.

15. The slurry of claim 13 , wherein a weight of the API Class G cement present in the slurry is about 0.1% to about 35% of a weight of the cement present in the slurry.

16. The slurry of claim 13 , wherein a weight of the API Class G cement present in the slurry is about 0.5% to about 10% of a weight of the cement present in the slurry.

17. The slurry of claim 9 , further comprising at least one retarder, wherein a total weight of the at least one retarder is about 0.1% to about 35% of a weight of the cement present in the slurry.

18. The slurry of claim 9 , further comprising:
zinc oxide;
diethylenetriamine penta(methylene phosphonic acid); and
a second copolymer comprising 2-acrylamido-2-methylpropane sulfonic acid monomer units and acrylic acid monomer units;

wherein:
a weight of the zinc oxide present in the slurry is about 0.1% to about 1% of a weight of the cement present in the slurry;
a weight of the diethylenetriamine penta(methylene phosphonic acid) present in the slurry is about 0.1% to about 1% of a weight of the cement present in the slurry; and
a weight of the second copolymer present in the slurry is about 0.1% to about 1% of the weight of the cement present in the slurry.

19. The slurry of claim 9 , further comprising at least one superplasticizer, wherein a total weight of the at least one superplasticizer present in the slurry is about 0.1% to about 5% of a weight of the cement present in the slurry.

20. The slurry of claim 9 , further comprising a polycarboxylate ether, wherein a weight of the polycarboxylate ether present in the slurry is about 0.1% to about 1.5% of a weight of the cement present in the slurry.

21. The slurry of claim 9 , further comprising a defoamer, wherein a total weight of the defoamer is about 0.001% to about 0.2% of a weight of the cement present in the slurry.

22. The slurry of claim 9 , wherein the cement and the water are present in the slurry in a weight ratio of about 3:1 to about 1:1.

23. The slurry of claim 9 , further comprising an API Class G cement, wherein:
the cement comprises a Portland cement;
a weight of the copolymer present in the slurry is about 0.05% to about 10% of a weight of the cement present in the slurry;
a weight of the graft copolymer present in the slurry is about 0.05% to about 10% of the weight of the cement present in the slurry;
a weight of the API Class G cement present in the slurry is about 0.1% to about 35% of the weight of the cement present in the slurry; and
the cement and the water are present in the slurry in a weight ratio of about 3:1 to about 1:1.

24. The slurry of claim 9 , comprising a fluid loss of about 0 mL per 30 min. to about 150 mL per 30 min., measured at an operating temperature of about 180° F. according to API Recommended Practice 10B-2.

25. The slurry of claim 9 , comprising a fluid loss of about 0 mL per 30 min to about 50 mL per 30 min., measured at an operating temperature of about 180° F. according to API Recommended Practice 10B-2.

26. The slurry of claim 9 , comprising a density of about 10 lbs./gal. to about

Assignees

• Saudi Arabian Oil Co

Inventors

• Boul Peter
• Johnson Kenneth Dejuan

Classifications

• C04B14/30

  Oxides other than silica {(ferrites C04B14/363)} · CPC title

• C04B2103/46

  Water-loss or fluid-loss reducers, hygroscopic or hydrophilic agents, water retention agents · CPC title

• C04B2103/32

  Superplasticisers · CPC title

• C04B2103/0035

  Type G · CPC title

• C04B2103/0059

  Graft (co-)polymers · CPC title