Some reservoirs have tight oil formations, such as the Changqing reservoir. The surfactant polymer flooding and low tension gas flooding are two potential chemical flooding methods for use in tight oil formations. In these methods, an oil displacement agent, or surfactant, is added. Nonionic surfactants with extended chains (by propylene oxide and ethylene oxide) from dialkyl alcohols or dialkyl amines were tested. A synergistic blend of surfactants was developed between the nonionic surfactants and anionic surfactants that lowers interfacial tension and improves surfactant solubility in water and oil.

Some reservoirs have tight oil formations, such as the Changqing reservoir. The surfactant polymer flooding and low tension gas flooding are two potential chemical flooding methods for use in tight oil formations. In these methods, an oil displacement agent, or surfactant, is added. Nonionic surfactants with extended chains (by propylene oxide and ethylene oxide) from dialkyl alcohols or dialkyl amines were tested. A synergistic blend of surfactants was developed between the nonionic surfactants and anionic surfactants that lowers interfacial tension and improves surfactant solubility in water and oil.

A method for exploiting a natural gas hydrate reservoir includes drilling a borehole entering the natural gas hydrate reservoir; perforating the borehole to form perforations; fracturing the natural gas hydrate reservoir via the perforations by using a gas containing calcium oxide powder having a particle size 0.001 to 10 mm to generate a fracture; and collecting natural gas released by the natural gas hydrate. The method is easy to operate, cost-effective, and suitable for commercial applications.

A method for exploiting a natural gas hydrate reservoir includes drilling a borehole entering the natural gas hydrate reservoir; perforating the borehole to form perforations; fracturing the natural gas hydrate reservoir via the perforations by using a gas containing calcium oxide powder having a particle size 0.001 to 10 mm to generate a fracture; and collecting natural gas released by the natural gas hydrate. The method is easy to operate, cost-effective, and suitable for commercial applications.

The invention relates to a composition which comprises within an aqueous medium: —at least one ethoxylated alkylamine; and—at least one amphoteric or zwitterionic surfactant. The invention further relates to the use of said compositions as foaming compositions, in particular for EOR (enhanced oil recovery).

The invention relates to a composition which comprises within an aqueous medium: —at least one ethoxylated alkylamine; and—at least one amphoteric or zwitterionic surfactant. The invention further relates to the use of said compositions as foaming compositions, in particular for EOR (enhanced oil recovery).

This document relates to energetic salts that contain an organic cation and an oxidizing anion and methods of using the energetic salt compositions, including methods of hydraulic fracturing, pressure pulse fracturing, formation damage removal, and lowering the viscosity of heavy oil.

An apparatus for producing steam in-situ, the apparatus comprising an activated carbon container configured to hold activated carbon; a water supply fluidly connected to the activated carbon container, the water supply configured to provide water directly to the activated carbon container; an inter-container valve fluidly connected to the activated carbon container, the inter-container valve configured to let steam flow from the activated carbon container to a steam container; the steam container fluidly connected to the inter-container valve, the steam container configured to hold the steam that flows from the activated carbon container; and one or more release valves fluidly connected to the steam container, the one or more release valves configured to release steam from the steam container.

An apparatus for producing steam in-situ, the apparatus comprising an activated carbon container configured to hold activated carbon; a water supply fluidly connected to the activated carbon container, the water supply configured to provide water directly to the activated carbon container; an inter-container valve fluidly connected to the activated carbon container, the inter-container valve configured to let steam flow from the activated carbon container to a steam container; the steam container fluidly connected to the inter-container valve, the steam container configured to hold the steam that flows from the activated carbon container; and one or more release valves fluidly connected to the steam container, the one or more release valves configured to release steam from the steam container.

Techniques including methods, apparatus and computer program products are disclosed for determining an amount of hydrocarbon recoverable from porous reservoir rock by a miscible gas flood. The techniques include retrieve a representation of a physical porous reservoir rock sample (porous reservoir rock), the representation including pore space and grain space data corresponding to the porous reservoir rock, subsequent to an execution of a multiphase flow simulation to obtain predictions of flow behavior of oil in the presence of a waterflood of the porous reservoir rock, locate substantially immobile oil blobs or patches in the retrieved representation of the porous reservoir rock; and for N number of substantially immobile oil blobs or patches (blobs), evaluate changes in mobility of the blobs for two or more iterations an effort level for of a given EOR technique, with a first one of the two or more iterations expending a first level of effort and a second one of the two or more iterations expending a second, higher level of effort, to estimate an amount of change in mobilization of the blob between the first and the second iterations for the given EOR technique.