摘要:
The disclosed invention provides a method for recovering hydrocarbons from a subterranean formation by injecting an emulsion, comprising oil and water, into the formation. More specifically, the emulsion is stabilized using undissolved solid particles, which are preferably at least partially oleophilic. The solids-stabilized emulsion may be used either as a drive fluid for displacing hydrocarbons from the formation or to produce a barrier for diverting flow of fluids in the formation. Such solid particles may be either formation solid particles (i.e., indigenous to the formation) or nonformation solid particles (i.e., obtained from outside the formation). Nonformation solid particles may either be naturally occurring or synthetic. Some preferred solids include clays, quartz, feldspar, gypsum, coal dust, asphaltenes, and polymers.
摘要:
To improve the separation of a produced oil-water emulsion containing a surfactant, the emulsion parameters of temperature and salinity are brought within certain critical limits. The emulsion will separate into an injectable brine/surfactant phase and a pipeline quality crude oil phase. The operable salinity range is from about 70% to about 130% of the reservoir salinity, and the operable temperature range is from about 75.degree. F. lower to about 75.degree. F. higher than the temperature of the reservoir from which the emulsion was produced.
摘要:
An improved method of producing hydrocarbons from a subterranean formation in which a solids-stabilized emulsion (SSE) is formed, the SSE comprising oil as a first liquid, droplets of a second liquid suspended in the oil, and solid particles that are insoluble in both the oil and the second liquid at the conditions of the subterranean formation. The SSE with dissolved gas is injected into the subterranean formation as a drive fluid, and at least a portion of the SSE is placed into one or more area of the subterranean formation having an in situ pressure sufficiently lower than the selected partial pressure to permit evolution of at least a portion of the gas from the oil. Furthermore, a method of making the foamy SSE is also provided.
摘要:
A waxy oil-external emulsion is provided for injection into a selected zone of a subsurface formation. The selected zone is typically a high permeability zone. The emulsion generally comprises oil, added wax, and water. The emulsion may also include an emulsifying agent and a solvent. The emulsion is formulated to be a liquid at a temperature greater than a targeted temperature in the subsurface formation, but a solid at the targeted temperature. The targeted temperature is typically the maximum operating temperature for the formation. A method of formulating the emulsion is also provided. Further, a method of plugging a high permeability zone using the emulsion is disclosed.
摘要:
A method is disclosed for concentrating surfactant in an aqueous solution. The method comprises adding to the solution a component incompatible with the surfactant, such as a water-soluble polymer, thereby displacing the surfactant from the aqueous phase of the solution. The component remains in the aqueous phase and the surfactant goes into a surfactant-rich phase. The surfactant-rich phase can then be separated from the aqueous phase by conventional separation devices or techniques. This method is particularly applicable to concentrating surfactant recovered from a reservoir following an enhanced oil recovery process employing surfactant. The method may be practiced in the field or off-site.
摘要:
A method is disclosed for determining the relative amounts of two fluid phases in a subterranean formation, one phase being mobile and the other being substantially immobile. A sweep fluid which is substantially free of the immobile fluid is injected into the formation by means of a well in an amount such that a measurable first portion of the sweep fluid in the formation adjacent the injection well remains unsaturated with the immobile fluid, and a second portion adjacent the first portion becomes saturated. The sweep fluid is then produced from the formation, preferably by means of the injection well. The concentration of immobile fluid dissolved in the produced sweep fluid is measured as a function of volume produced to determine the volumes of the two sweep fluid portions; these volumes are then used to calculate the relative amounts of the two fluid phases in the formation.
摘要:
A waxy oil-external emulsion is provided for injection into a selected zone of a subsurface formation. The selected zone is typically a high permeability zone. The emulsion generally comprises oil, added wax, and water. The emulsion may also include an emulsifying agent and a solvent. The emulsion is formulated to be a liquid at a temperature greater than a targeted temperature in the subsurface formation, but a solid at the targeted temperature. The targeted temperature is typically the maximum operating temperature for the formation. A method of formulating the emulsion is also provided. Further, a method of plugging a high permeability zone using the emulsion is disclosed.
摘要:
An improved method of producing hydrocarbons from a subterranean formation in which a solids-stabilized emulsion (SSE) is formed, the SSE comprising oil as a first liquid, droplets of a second liquid suspended in the oil, and solid particles that are insoluble in both the oil and the second liquid at the conditions of the subterranean formation. The SSE with dissolved gas is injected into the subterranean formation as a drive fluid, and at least a portion of the SSE is placed into one or more area of the subterranean formation having an in situ pressure sufficiently lower than the selected partial pressure to permit evolution of at least a portion of the gas from the oil. Furthermore, a method of making the foamy SSE is also provided.
摘要:
An aqueous heteropolysaccharide solution is treated to improve its injectivity into a subterranean hydrocarbon reservoir by passing the solution through a colloid mill.
摘要:
A method for determining the relative amounts of two fluid phases in a subterranean formation containing one mobile phase and a substantially immobile phase. A fluid which is substantially free of the immobile phase is injected into the formation by means of a well in an amount such that a portion of the injected fluid in the formation remains unsaturated with the immobile phase. The injected fluid is then preferably produced from the formation by means of the injection well. In another embodiment, the injected fluid is produced from the formation by means of a second well. The concentration of immobile fluid dissolved in the produced fluid is measured to determine the relative amounts of the two fluid phases in the formation.