Alumina wellbore cement composition

• US 5,488,991 A
• Filed: 10/24/1994
• Issued: 02/06/1996
• Est. Priority Date: 10/24/1994
• Status: Expired due to Term

• Current Assignee: Shell Oil Company (Shell Plc)
• Original Assignee: Shell Oil Company (Shell Plc)
• Inventors: Cowan, Kenneth M., Nahm, James J. W., Romero, Robert N., Wyant, Reece E.
• Primary Examiner(s): MARCANTONI, PAUL D
• Application Number:
  US08/327,725
• Time in Patent Office: 470 Days
• Field of Search: 166/292, 166/293, 166/294, 166/295, 106/692, 106/696, 106/724, 106/802, 106/819, 106/823, 106/900, 106/822, 405/266, 405/267
• US Class Current: 166/293
• CPC Class Codes: C04B 14/303 Alumina
• CPC Class Codes: C04B 18/146 Silica fume
• CPC Class Codes: C04B 2103/20 Retarders
• CPC Class Codes: C04B 2103/22 Set retarders
• CPC Class Codes: C04B 2103/30 Water reducers, plasticisers, air-entrainers, flow improvers
• CPC Class Codes: C04B 24/18 Lignin sulfonic acid or derivatives thereof, e.g. sulfite lye
• CPC Class Codes: C04B 24/243 Phosphorus-containing polymers
• CPC Class Codes: C04B 28/06 Aluminous cements monolithic refractories or refractory mortars C04B35/66
• CPC Class Codes: C09K 8/46 containing inorganic binders, e.g. Portland cement
• CPC Class Codes: Y02W 30/91 Use of waste materials as fillers for mortars or concrete

Abstract

A high alumina wellbore cementing composition is provided, the composition comprising:

a) high alumina cement; and

b) a polyacrylic acid phosphinate having a molecular weight of about 3800 in an amount effective to prevent gelation of the cementing composition for a time period of at least three hours.

This composition can remain pumpable for a time period sufficiently long to place the cement in a wellbore using conventional wellbore cementing procedures, and, after the composition is cured, is capable of withstanding elevated wellbore temperatures.

Claims

1. A high alumina wellbore cementing composition comprising:

a) high alumina cement; and

b) a polyacrylic acid phosphinate having a molecular weight of about 3800 in an amount effective to prevent gelation of the cementing composition for a time period of at least three hours.

2. The wellbore cementing composition of claim 1 further comprising an additional component effective as a set retarder.

3. The wellbore cementing composition of claim 1 further comprising an additional component effective as a retarder selected from the group consisting of:

dicarboxylates, gluconates, reducing sugars, acids of reducing sugars, phosphinic acids and salts thereof, and phosphonic acids and salts thereof.

4. The wellbore cementing composition of claim 1 further comprising lignosulfonate.

5. The wellbore cementing composition of claim 1 further comprising a alumina aggregate.

6. The wellbore cementing composition of claim 1 further comprising fume silica.

7. A method to cement a wellbore wherein the wellbore will be exposed to elevated temperatures comprising the steps of:

providing a cementing composition, the cementing composition comprising a) high alumina cement, and b) a polyacrylic acid phosphinate having a molecular weight of about 3800 in an amount effective to prevent gelation of the cementing composition for a time period of at least three hours;

placing the cementing composition in the wellbore prior to gelation of the cementing composition; and

allowing the cementing composition to set within the wellbore.

8. The method of claim 7 wherein the wellbore cementing composition further comprises an additional component effective as a set retarder.

9. The method of claim 7 wherein the cementing composition further comprises an additional component effective as a retarder selected from the group consisting of:

dicarboxylates, gluconates, reducing sugars, acids of reducing sugars, and phosphonic acids and salts thereof.

10. The method of claim 7 wherein the wellbore cementing composition 11 further comprises lignosulfonate.

11. The method of claim 7 wherein the wellbore cementing composition further comprises a alumina aggregate.

12. The method of claim 7 wherein the wellbore cementing composition further comprises fume silica.