Method of cementing an area of a borehole with aqueous cement spacer system
AssigneeBJ Services Company
InventorsCharles Joseph Fanguy, Jr., Jerry Patrick Sanchez, Timothy Ivan Mitchell
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Abstract
A storable cement system comprises a suspending agent, a cement spacer and water. The composition may further optional contain a surfactant and/or an organic solvent and/or a weighting material. The suspending agent is preferably a carrageenan or scleroglucan. The cement system may be stored for an extended period of time prior to being interposed between a cement slurry and a drilling fluid. As such, the aqueous cement system may be made off-site and used when desired for preventing contact between non-compatible hydrocarbonaceous and aqueous fluids.
Claims24
A method of cementing an area of a borehole containing an oil base composition having dispersants therein, which comprises:
- formulating an aqueous storable cement system by mixing together a cement spacer, water, and a hydrated suspending agent;
- storing the aqueous storable cement system for an extended time;
- and
- interposing the aqueous storable cement system between a cementitious slurry and the oil base composition within the borehole.
A method of cementing an area of a borehole penetrating a subterranean formation, the method comprising the steps of:
- (A) formulating an aqueous storable cement system by:
- (i) mixing fresh water and a suspending agent for a time sufficient to hydrate the suspending agent;
- (ii) introducing a cement spacer to the mixture containing the hydrated suspending agent;
- and
- (iii) stirring for a time sufficient to render a homogeneous cement system;
- (B) storing the storable cement system for an extended period of time;
- and
- (C) interposing the aqueous storable cement system between a cement slurry and a drilling mud within the borehole.
A method of emplacing an aqueous cementitious slurry into a well bore containing a drilling fluid, which comprises:
- (A) formulating an aqueous storable cement spacer system by:
- (i) mixing fresh water and a suspending agent for a time sufficient to hydrate the suspending agent;
- (ii) introducing to the mixture containing the hydrated suspending agent a cement spacer comprising welan gum:
- (iii) stirring the mixture of step (ii) for a time sufficient to render a homogeneous cement system;
- (B) storing the aqueous storable cement spacer system for an extended period of time;
- and
- (C) introducing the aqueous storable cement spacer system into a well bore containing a drilling fluid;
- (D) displacing at least a portion of the drilling fluid from an area in the well bore into which the cement slurry is to be emplaced with the aqueous storable cement spacer system;
- (E) displacing at least a portion of the aqueous storable cement spacer system from the area in the well bore with the cementitious slurry;
- and
- (F) permitting the cementitious slurry to harden.
A method of cementing an area of a borehole containing an oil base composition having dispersants therein, which comprises:
- formulating an aqueous storable cement system by mixing together a cement spacer, water, and a suspending agent, wherein the suspending agent is at least one member selected from the group consisting of carrageenan or scleroglucan;
- storing the aqueous storable cement system for a desired time;
- and
- interposing the aqueous storable cement system between a cementitious slurry and the oil base composition within the borehole.
A method of cementing an area of a borehole, which comprises:
- storing an aqueous storable cement system for a desired time, the storable cement system having been prepared from a cement spacer, water, and a hydrated suspending agent;
- and
- interposing the aqueous storable cement system between a cementitious slurry and the oil base composition within the borehole.
Dependencies are inferred from the claim text.