A cement slurry composition, containing hydraulic cement, water, and from 1 to less than 4% of an organically modified nanoclay. A method for cementing a high pressure high temperature well by pumping the cement composition of claim 1 between a casing and a formation of a well bore to fill a gap between the casing and the formation, and allowing the cement to harden.

A cement slurry composition, containing hydraulic cement, water, and from 1 to less than 4% of an organically modified nanoclay. A method for cementing a high pressure high temperature well by pumping the cement composition of claim 1 between a casing and a formation of a well bore to fill a gap between the casing and the formation, and allowing the cement to harden.

Amphiphilic macromolecules having repeating structural units: structural units to adjust molecular weight and molecular weight distribution and charging property effects, high stereo-hindrance structural units, and amphiphilic structural units, which are suitable for fields such as oil field well drilling, well cementation, fracturing, oil gathering and transfer, sewage treatment, sludge treatment and papermaking, etc., and can be used as an oil-displacing agent for enhanced oil production, a heavy oil viscosity reducer, a fracturing fluid, a clay stabilizing agent, a sewage treatment agent, a papermaking retention and drainage aid or a reinforcing agent, etc.

A cement composition for use in a well that penetrates a subterranean formation comprises: a calcium aluminate cement or calcium magnesia cement; water; a fluid loss additive; and a suspending agent, wherein the suspending agent is a polymer and wherein the polymer: (A) is amphoteric; (B) has a molecular weight greater than 100,000; and (C) does not increase the fluid loss of the cement composition greater than 15% at a temperature of 145° F. (63° C.) and a pressure differential of 1,000 psi (7 MPa) compared to a cement composition consisting of the cement, the water, and the fluid loss additive. A method of cementing in a subterranean formation comprises: introducing the cement composition into the subterranean formation; and allowing the cement composition to set.

A cement composition for use in a well that penetrates a subterranean formation comprises: a calcium aluminate cement or calcium magnesia cement; water; a fluid loss additive; and a suspending agent, wherein the suspending agent is a polymer and wherein the polymer: (A) is amphoteric; (B) has a molecular weight greater than 100,000; and (C) does not increase the fluid loss of the cement composition greater than 15% at a temperature of 145° F. (63° C.) and a pressure differential of 1,000 psi (7 MPa) compared to a cement composition consisting of the cement, the water, and the fluid loss additive. A method of cementing in a subterranean formation comprises: introducing the cement composition into the subterranean formation; and allowing the cement composition to set.

The present invention relates to the use of a sequenced polymer as an agent for monitoring the filtrate in a fluid injected under pressure into an oil rock, wherein the fluid comprises solid particles and/or is brought into contact with solid particles within the oil rock after being injected, the polymer comprising at least three blocks, including: at least one first block which is adsorbed, preferably irreversibly, onto at least some of the particles (p); a second block (B) having a composition other than that of the first and a mean molecular weight of more than 10,000 g/mol, and which is soluble in the fluid (F); and at least one third block of type (A) or type (B).

A cement composition for use in a well that penetrates a subterranean formation comprising: cement; water; an environmentally-friendly curable resin having two or more epoxy functional groups; and a curing agent that causes the curable resin to cure when in contact with the curing agent. A method of cementing in a subterranean formation comprising: introducing the cement composition into the subterranean formation; and allowing the cement composition to set after introduction.

A cement composition for use in a well that penetrates a subterranean formation comprising: cement; water; an environmentally-friendly curable resin having two or more epoxy functional groups; and a curing agent that causes the curable resin to cure when in contact with the curing agent. A method of cementing in a subterranean formation comprising: introducing the cement composition into the subterranean formation; and allowing the cement composition to set after introduction.

Some embodiments of the present invention comprise a method of cementing comprising: placing a settable composition into a well bore, the settable composition comprising remediated coal ash, hydraulic cement, and water; and allowing the settable composition to set. Other embodiments comprise a method of cementing comprising: placing a settable composition into a well bore, the settable composition comprising remediated coal ash, calcium hydroxide (lime), and water; and allowing the settable composition to set. Other embodiments comprise a settable composition comprising: remediated coal ash, hydraulic cement, calcium hydroxide, natural pozzolan and water; and allowing the composition to set. Other embodiments comprise a settable composition comprising remediated coal ash and any combination of hydraulic cement, calcium hydroxide, slag, fly ash, and natural or other pozzolan.

Some embodiments of the present invention comprise a method of cementing comprising: placing a settable composition into a well bore, the settable composition comprising remediated coal ash, hydraulic cement, and water; and allowing the settable composition to set. Other embodiments comprise a method of cementing comprising: placing a settable composition into a well bore, the settable composition comprising remediated coal ash, calcium hydroxide (lime), and water; and allowing the settable composition to set. Other embodiments comprise a settable composition comprising: remediated coal ash, hydraulic cement, calcium hydroxide, natural pozzolan and water; and allowing the composition to set. Other embodiments comprise a settable composition comprising remediated coal ash and any combination of hydraulic cement, calcium hydroxide, slag, fly ash, and natural or other pozzolan.