Herein are provided tools and processes for extracting oil from subterranean formation. The processes can include lightening the oil in the formation prior to extraction by the addition of a nanogas solution. The tools include injectors for the formation of the nanogas solution within the subterranean formation.

A method of recovering crude oil from a reservoir by: determining a depletion pressure for providing a lights-depleted crude oil comprising a reduced amount of light ends including methane, nitrogen, carbon dioxide (CO.sub.2), or a combination thereof and having a CO.sub.2 multi contact Minimum Miscibility Pressure (CO.sub.2-MMP) below a CO.sub.2-MMP of a native crude oil, wherein the native crude oil is crude oil extracted from the reservoir prior to primary oil recovery therefrom; depleting the pressure of the reservoir from an initial reservoir pressure to the determined depletion pressure, thus providing the lights-depleted crude oil; repressurizing the reservoir to an operating pressure for recovering the lights-depleted crude oil from the reservoir via carbon dioxide (CO.sub.2) injection; injecting CO.sub.2 into the reservoir via at least one injection well; and recovering at least a portion of the lights-depleted crude oil from the reservoir via at least one production well.

A thermal fluid generator utilizes a plasma energy heat source to generate steam, and combine the steam with nitrogen gas. Combined flow streams of steam and heated nitrogen are injected downhole into subterranean reservoir to thermally stimulate the flow of hydrocarbons (such as, for example, residual oil) from a reservoir, while also increasing fluid pressure in the reservoir. The thermal fluid generator can be located at the earth's surface, or positioned downhole within a wellbore.

The invention discloses an integrated method for nitrogen-assisted carbon dioxide fracturing and development of shale oil reservoirs, comprising the following steps: fracture the target shale reservoir with nitrogen-assisted carbon dioxide; after fracturing, firstly inject carbon dioxide gas into the target shale oil reservoir, and then inject nitrogen gas to push the carbon dioxide gas into the further location of the oil reservoir; shut in the well in the target shale oil reservoir; after shut-in, open the well to implement depletion production; after the first cycle of production, the slug volume of the injected gas and the shut-in time are 1.5 times of those in the previous cycle in the subsequent production, and Steps 5 to 7 are repeated for each cycle. The present invention maximizes the recovery efficiency of shale oil reservoirs; in this way, carbon dioxide gas can be used most efficiently, making the development of shale reservoir more economical and efficient; the integrated fracturing and development design enables the field operation to be streamlined and standardized, and thus different departments to cooperate each other closer.

An experimental method and apparatus for CO.sub.2 displacement process of ultra-low permeability oil reservoir are provided. The apparatus comprises a displacement container and a core holder. The displacement container comprises a water container, an oil container and a gas container. The core holder is respectively connected with the water container, the oil container and the gas container through a connecting pipe; and the core holder connects with a gas-liquid separator through the connecting pipe. By designing the experimental apparatus, the problem of deviation of the experimental result caused by the reduction of the accuracy of the experimental apparatus is solved. Under the condition that the accuracy of the experiment is guaranteed, a relatively reasonable injection mode is obtained through the designed experimental method, and the recovery efficiency is improved.

A method for concurrent fluid injection and production of a reservoir fluid from a hydraulically fractured horizontal well comprising the steps of completing a well in a formation to create the hydraulically fractured horizontal well; designating an alpha group; designating a beta group, such that each segment is in either the alpha group or the beta group, wherein the number and location of the segments in each of the alpha group and the beta group are based on the production configuration; initiating a first mode of operation; operating the hydraulically fractured horizontal well in the first mode of operation for a first mode run time; stopping the first mode of operation; initiating the second mode of operation; operating the hydraulically fractured horizontal well in the second mode of operation for a second mode run time; and cycling between the first mode of operation and the second mode of operation.

An apparatus utilizes a membrane unit to capture components from atmospheric air, including carbon dioxide, enriches the carbon dioxide concentration, and delivers the enriched concentration of carbon dioxide to a sequestering facility. The membrane is configured such that as a first gas containing oxygen, nitrogen and carbon dioxide is drawn through the membrane, a permeate stream is formed where the permeate stream has an oxygen concentration and a carbon dioxide concentration higher than in the first gas and a nitrogen concentration lower than in the first gas. A permeate conduit, having a vacuum applied to it by a vacuum generating device receives the permeate stream and a delivery conduit delivers at least a portion of the enriched carbon dioxide to a sequestering facility. The apparatus may comprise a component of a system where the system may have a flue gas generator and/or a secondary enrichment system disposed between the vacuum generating device and the sequestering facility.

The disclosed technology relates to a composition and method of increasing the viscosity of a carbon dioxide composition, as well as a method of increasing the production and recovery of hydrocarbons from an underground formation employing the viscosified carbon dioxide composition.

Apparatuses, systems, and methods are disclosed for producing and liberating hydrogen gas and sequestering carbon dioxide through sequential serpentinization and carbonation (mineralization) reactions conducted in situ via one or more wellbores that at least partially traverse subterranean geological formations having large concentrations of mafic igneous rock, ultramafic igneous rock, or a combination thereof.

A method of preventive well maintenance with pumping equipment in the well for well rehabilitation using CO.sub.2 with varying lengths of producing intervals utilizing varying methods to deliver cleaning energy and varying porosity of aquifers to determine varying quantities of energy over the entire well structure.