The present application provides a gas-generating aqueous fluid containing a gas-generating compound like an azo compound, and an organic amine like a primary, secondary or tertiary amine, a hydrazine, a hydrazide, or a semicarbazide. The aqueous fluid may also a viscosifier, and a foaming surfactant. The present application also provides a method of using the gas-generating composition to modulate density of a wellbore fluid for use in downhole applications. The method optionally includes adding an oxidizer to the wellbore fluid.

A composition containing a quaternary organosilane foaming agent capable of foaming various liquids in order to remove the liquids from subterranean wells is described. For instance, the composition can be used to remove hydrocarbon condensate liquids from a gas well or an oil well. Of particular advantage, the composition can foam liquids containing substantial amounts of hydrocarbons.

A composition containing a quaternary organosilane foaming agent capable of foaming various liquids in order to remove the liquids from subterranean wells is described. For instance, the composition can be used to remove hydrocarbon condensate liquids from a gas well or an oil well. Of particular advantage, the composition can foam liquids containing substantial amounts of hydrocarbons.

The disclosure discloses an ultra-dry three-phase flue gas foam for oil-gas fields and preparation method thereof. The ultra-dry three-phase flue gas foam is produced by a gas phase, a liquid phase and a solid phase; the gas phase is a flue gas; the foaming solution is an aqueous solution of a surfactant, a pH adjuster, and an inorganic salt; the solid phase is a composite of fly ash and nano silica; the foam quality is 90%-99%. The solid phase foam stabilizer is a compounded system of fly ash particles and nano silica particles, which is not only low in cost but also can form a stable solid particle adsorption layer on the foam film. Thus the instability of the foam such as film rupture, gas diffusion and bubble aggregation can be greatly reduced, and the stability of the foam can be effectively improved.

The disclosure discloses an ultra-dry three-phase flue gas foam for oil-gas fields and preparation method thereof. The ultra-dry three-phase flue gas foam is produced by a gas phase, a liquid phase and a solid phase; the gas phase is a flue gas; the foaming solution is an aqueous solution of a surfactant, a pH adjuster, and an inorganic salt; the solid phase is a composite of fly ash and nano silica; the foam quality is 90%-99%. The solid phase foam stabilizer is a compounded system of fly ash particles and nano silica particles, which is not only low in cost but also can form a stable solid particle adsorption layer on the foam film. Thus the instability of the foam such as film rupture, gas diffusion and bubble aggregation can be greatly reduced, and the stability of the foam can be effectively improved.

Methods for servicing a hydrocarbon well using natural gas are provided. The method can include preparing a working fluid comprising about 5 vol % to about 100 vol % of natural gas. A quantity of the natural gas in the working fluid can be sufficient to form a heterogeneous phase well servicing mixture of a gaseous phase natural gas and a solid or liquid phase recovery target material under specified well intervention conditions. During the well servicing operation and under the specified well intervention conditions, the working fluid can be injected into the well and mixing the working fluid with the recovery target material in the well to form the heterogeneous phase well servicing mixture. The natural gas can be in a gas phase and can serve as a carrier fluid for the recovery target material. At least a portion of the heterogeneous phase well servicing mixture can be recovered at surface.

Methods for servicing a hydrocarbon well using natural gas are provided. The method can include preparing a working fluid comprising about 5 vol % to about 100 vol % of natural gas. A quantity of the natural gas in the working fluid can be sufficient to form a heterogeneous phase well servicing mixture of a gaseous phase natural gas and a solid or liquid phase recovery target material under specified well intervention conditions. During the well servicing operation and under the specified well intervention conditions, the working fluid can be injected into the well and mixing the working fluid with the recovery target material in the well to form the heterogeneous phase well servicing mixture. The natural gas can be in a gas phase and can serve as a carrier fluid for the recovery target material. At least a portion of the heterogeneous phase well servicing mixture can be recovered at surface.

A method comprising: providing a composition comprising: a base liquid; and solid particles; foaming the composition with a gas to produce a foamed drilling fluid; wherein the foamed drilling fluid is characterized as a Pickering foam wherein at least a portion of the solid particles are dispersed on an interface between the base liquid and the gas to stabilize the Pickering foam; pumping the foamed drilling fluid through a drill string; and extending a wellbore through a subterranean formation.

A method comprising: providing a composition comprising: a base liquid; and solid particles; foaming the composition with a gas to produce a foamed drilling fluid; wherein the foamed drilling fluid is characterized as a Pickering foam wherein at least a portion of the solid particles are dispersed on an interface between the base liquid and the gas to stabilize the Pickering foam; pumping the foamed drilling fluid through a drill string; and extending a wellbore through a subterranean formation.

The present application provides a gas-generating aqueous fluid containing a gas-generating compound like an azo compound, and an organic amine like a primary, secondary or tertiary amine, a hydrazine, a hydrazide, or a semicarbazide. The aqueous fluid may also a viscosifler, and a foaming surfactant. The present application also provides a method of using the gas-generating composition to modulate density of a wellbore fluid for use in downhole applications. The method optionally includes adding an oxidizer to the wellbore fluid.