Abstract: The effectiveness of expansive cement systems may be diluted when, during a well cementing operation, commingling takes place between the cement slurry and a spacer fluid, a drilling fluid, or both. Incorporating expansive agents in the spacer fluid or drilling fluid may reduce or negate the loss of expansion at the cement slurry/spacer interface or the cement slurry/drilling fluid interface, thereby promoting zonal isolation throughout the cemented interval.

Abstract: Described herein are methods of treating cement leaks in a hydrocarbon well. The methods include detecting a leak in a cement structure of the well, in response to detection of the leak, flowing a stimulus fluid containing hydrocarbon species into the well in contact with the cement structure, and monitoring flow of the stimulus fluid to observe closure of a leakage pathway of the cement structure.

Abstract: Methods for shortening the waiting-on-cement (WOC) time during primary and remedial cementing operations are disclosed. A fluid pill is injected into the wellbore that comprises reactants. The reaction is exothermic and heat is conducted into the cement sheath, thereby accelerating hydration and shortening the time necessary for the slurry to set and harden.

Abstract: Methods for shortening the waiting-on-cement (WOC) time during primary and remedial cementing operations are disclosed. A fluid pill is injected into the wellbore that comprises reactants. The reaction is acclerating hydration and shortening the time necessary for the slurry to set and harden.

Abstract: The effectiveness of expansive cement systems may be diluted when, during a well cementing operation, commingling takes place between the cement slurry and a spacer fluid, a drilling fluid, or both. Incorporating expansive agents in the spacer fluid or drilling fluid may reduce or negate the loss of expansion at the cement slurry/spacer interface or the cement slurry/drilling fluid interface, thereby promoting zonal isolation throughout the cemented interval.

Abstract: Geopolymeric compositions are presented that are useful for cementing subterranean wells. The compositions may contain an aluminosilicate source, a metal silicate, an alkali activator and a slurry density modifier that may contain uintaite, vitrified shale, petroleum coke or coal or combinations thereof. Methods for placing the geopolymeric compositions in subterranean wells are also presented.

Abstract: The effectiveness of expansive cement systems may be diluted when, during a well cementing operation, commingling takes place between the cement slurry and a spacer fluid, a drilling fluid, or both. Incorporating expansive agents in the spacer fluid or drilling fluid may reduce or negate the loss of expansion at the cement slurry/spacer interface or the cement slurry/drilling fluid interface, thereby promoting zonal isolation throughout the cemented interval.

Abstract: The method of fluid loss control is provided for the case of high-rate fluid loss. Two treatment fluids are provided, where a first treatment fluid comprising a carrier fluid, solids and a first polyelectrolyte, and a second treatment fluid comprising a carrier fluid and a second polyelectrolyte. Two polyelectrolytes in both treatment fluids are oppositely charged under the pumping conditions, being taken from the classes of polyanionic and polycationic polymers. Two treatment fluids are pumped separately to the zone with fluid loss. The mixing of two treatment fluids into the well creates low-permeability agglomerates that plugs the fluid leakage channel, preventing or reducing further fluid movement between the wellbore and subterranean formation. The plugging of thief zone can be temporary or permanent.

Abstract: The effectiveness of expansive cement systems may be diluted when, during a well cementing operation, commingling takes place between the cement slurry and a spacer fluid, a drilling fluid, or both. Incorporating expansive agents in the spacer fluid or drilling fluid may reduce or negate the loss of expansion at the cement slurry/spacer interface or the cement slurry/drilling fluid interface, thereby promoting zonal isolation throughout the cemented interval.

Abstract: The effectiveness of expansive cement systems may be diluted when, during a well cementing operation, commingling takes place between the cement slurry and a spacer fluid, a drilling fluid, or both. Incorporating expansive agents in the spacer fluid or drilling fluid may reduce or negate the loss of expansion at the cement slurry/spacer interface or the cement slurry/drilling fluid interface, thereby promoting zonal isolation throughout the cemented interval.

Abstract: The effectiveness of expansive cement systems may be diluted when, during a well cementing operation, commingling takes place between the cement slurry and a spacer fluid, a drilling fluid, or both. Incorporating expansive agents in the spacer fluid or drilling fluid may reduce or negate the loss of expansion at the cement slurry/spacer interface or the cement slurry/drilling fluid interface, thereby promoting zonal isolation throughout the cemented interval.

Abstract: The effectiveness of expansive cement systems may be diluted when, during a well cementing operation, commingling takes place between the cement slurry and a spacer fluid, a drilling fluid, or both. Incorporating expansive agents in the spacer fluid or drilling fluid may reduce or negate the loss of expansion at the cement slurry/spacer interface or the cement slurry/drilling fluid interface, thereby promoting zonal isolation throughout the cemented interval.

Abstract: The effectiveness of expansive cement systems may be diluted when, during a well cementing operation, commingling takes place between the cement slurry and a spacer fluid, a drilling fluid, or both. Incorporating expansive agents in the spacer fluid or drilling fluid may reduce or negate the loss of expansion at the cement slurry/spacer interface or the cement slurry/drilling fluid interface, thereby promoting zonal isolation throughout the cemented interval.

Abstract: Methods for shortening the waiting-on-cement (WOC) time during primary and remedial cementing operations are disclosed. A fluid pill is injected into the wellbore that comprises reactants. The reaction is acclerating hydration and shortening the time necessary for the slurry to set and harden.

Abstract: The method of fluid loss control is provided for the case of high-rate fluid loss. Two treatment fluids are provided, where a first treatment fluid comprising a carrier fluid, solids and a first polyelectrolyte, and a second treatment fluid comprising a carrier fluid and a second polyelectrolyte. Two polyelectrolytes in both treatment fluids are oppositely charged under the pumping conditions, being taken form the classes of polyanionic and polycationic polymers. Two treatment fluids are pumped separately to the zone with fluid loss. The mixing of two treatment fluids into the well creates low-permeability agglomerates that plugs the fluid leakage channel, preventing or reducing further fluid movement between the wellbore and subterranean formation. The plugging of thief zone can be temporary or permanent.

Abstract: The effectiveness of expansive cement systems may be diluted when, during a well cementing operation, commingling takes place between the cement slurry and a spacer fluid, a drilling fluid, or both. Incorporating expansive agents in the spacer fluid or drilling fluid may reduce or negate the loss of expansion at the cement slurry/spacer interface or the cement slurry/drilling fluid interface, thereby promoting zonal isolation throughout the cemented interval.

Abstract: The effectiveness of expansive cement systems may be diluted when, during a well cementing operation, commingling takes place between the cement slurry and a spacer fluid, a drilling fluid, or both. Incorporating expansive agents in the spacer fluid or drilling fluid may reduce or negate the loss of expansion at the cement slurry/spacer interface or the cement slurry/drilling fluid interface, thereby promoting zonal isolation throughout the cemented interval.

Abstract: The effectiveness of expansive cement systems may be diluted when, during a well cementing operation, commingling takes place between the cement slurry and a spacer fluid, a drilling fluid, or both. Incorporating expansive agents in the spacer fluid or drilling fluid may reduce or negate the loss of expansion at the cement slurry/spacer interface or the cement slurry/drilling fluid interface, thereby promoting zonal isolation throughout the cemented interval.

Abstract: Expansive cements for use in cementing subterranean wells comprise water, an inorganic cement and one or more particulate materials that swell upon contact with a water-immiscible fluid. The cements may further comprise a water-immiscible fluid. Such cements are designed to seal microannuli arising from the presence of water-immiscible fluids on casing surfaces, borehole wall surfaces or both.

Abstract: Expansive cements for use in cementing subterranean wells comprise water, an inorganic cement and one or more particulate materials that swell upon contact with a water immiscible fluid. The cements may further comprise a water immiscible fluid. Such cements are designed to seal microannuli arising from the presence of water immiscible fluids on casing surfaces, borehole wall surfaces or both.