Well cementing compositions and methods
AssigneeHalliburton Energy Services, Inc.
InventorCraig W. Roddy
Life of this patent
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Abstract
The present invention provides improved lightweight well cement compositions useful for performing a variety of cementing applications in subterranean formations and particularly for cementing conductor pipe in offshore wells. A preferred cement composition basically comprises a hydraulic cement, an effective amount of an iron salt selected from the group of ferric chloride, ferrous chloride or mixtures thereof to reduce the transition time of the composition, sufficient water to form a pumpable slurry, an effective amount of a foaming additive for producing a foamed slurry, and sufficient gas to foam the slurry.
Claims37
A method of cementing in a subterranean zone having a temperature of about 65° F. or less using a lightweight well cement composition comprising the steps of:
- preparing a pumpable lightweight cement slurry having a density of less than about 14 lbs/gal;
- reducing the transition time of the lightweight cement slurry by including an effective amount of an iron compound in the composition to reduce the transition time thereof;
- placing the slurry in the subterranean zone to be cemented wherein said zone has a temperature of about 65° F. or less;
- and
- allowing the slurry to set into a hard impermeable mass.
A method of reducing the transition time of a foamed well cement composition placed in a subterranean zone having a temperature of about 65° F. or less comprising the steps of:
- preparing a foamed well cement composition comprising a hydraulic cement, sufficient water to form a pumpable slurry, an effective amount of a foaming additive for producing a foamed slurry, and sufficient gas to produce the foamed slurry;
- reducing the transition time of the foamed slurry by including an effective amount of an iron compound in the composition to reduce the transition time thereof;
- placing the slurry in the subterranean zone to be cemented wherein said zone has a temperature of about 65° F. or less;
- and
- allowing the slurry to set into a hard impermeable mass.
A method of reducing the transition time of a foamed cement composition placed in a subterranean zone having a temperature of about 65° F. or less comprising the steps of:
- preparing a foamed well cement composition comprising hydraulic cement, sufficient water to form a pumpable slurry, an effective amount of a foaming additive for producing a foamed slurry, and sufficient gas to produce the foamed slurry;
- wherein said foaming additive comprises a single additive for foaming and stabilizing the slurry comprised of an ethoxylated alcohol ether sulfate surfactant of the formula
- H(CH2)a(OC2H4)bOSO3NH4+
- wherein a is an integer in the range of from about 6 to about 10 and b is an integer in the range of from about 3 to about 10 and the surfactant is present in the additive in an amount in the range of from about 60 to about 64 parts by weight, an alkyl or alkene amidopropyl betaine surfactant having the formula
- R—CONHCH2CH2CH2N+(CH3)2CH2CO2−
- wherein R is a radical selected from the group of decyl, cocoyl, lauryl, cetyl and oleyl and the surfactant is present in the additive in an amount in the range of from about 30 to about 33 parts by weight and an alkyl or alkene amidopropyl dimethyl amine oxide surfactant having the formula
- R—CONHCH2CH2CH2N+(CH3)2O−
- wherein R is a radical selected from the group of decyl, cocoyl, lauryl, cetyl and oleyl and the surfactant is present in the additive in an amount in the range of from about 3 to about 10 parts by weight;
- reducing the transition time of the foamed slurry by including an effective amount of an iron compound in the composition to reduce the transition time thereof;
- placing the slurry in the subterranean zone to be cemented wherein said zone has a temperature of about 65° F. or less;
- and
- allowing the slurry to set into a hard impermeable mass.
A method for cementing a conductor pipe in a well bore having a temperature of about 65° F. or less in a seafloor in a water depth over 1000 feet comprising the steps of:
- preparing a foamed well cement composition comprising:
- Portland cement;
- an iron salt selected from the group consisting of ferric chloride, ferrous chloride and mixtures thereof present in an amount in the range of from about 0.1 to about 10 percent by weight of said composition;
- sufficient water selected from the group consisting of fresh water, unsaturated salt solutions and saturated salt solutions to form a pumpable slurry;
- an effective amount of a foaming additive for producing a foamed slurry;
- and
- sufficient gas to produce the foamed slurry;
- introducing the slurry into the conductor pipe whereby it is caused to flow through the pipe and return from the lower end thereof through an annulus present between the pipe and the well bore to the surface of the seafloor wherein the annulus has a temperature of about 65° F. or less;
- and
- maintaining the slurry in the annulus for a sufficient time to enable the slurry to form a rigid cement sheath whereby influx of fluids into the well bore is prevented.
A method of cementing in a subterranean zone having a temperature of about 65° F. or less comprising the steps of:
- preparing a cement composition comprising hydraulic cement, an iron compound present in an amount sufficient to reduce the transition time of the cement composition, and sufficient water to form a pumpable slurry;
- placing the slurry in the subterranean zone having a temperature of about 65° F. or less;
- and
- allowing the slurry to set into a hard impermeable mass.
Dependencies are inferred from the claim text.