Abstract: The invention relates to the recovery of heavy oil reservoirs, and more particularly to a supported catalyst-assisted microwave method for exploiting a heavy oil reservoir. The method includes: (1) injecting a slug of a supported catalyst fluid into the heavy oil reservoir; (2) placing a microwave generator in the heavy oil reservoir to perform volumetric heating on an oil layer containing the supported catalyst fluid; and (3) turning off the microwave generator and injecting water into the heavy oil reservoir for subsequent displacement, where a water injection rate is 3 m/d or less.

Abstract: A laboratory device for simulating the cement sheath consolidation in the frozen soil strata includes the main body, the pressure system and the measuring system. The main body includes the fixing plate, the detachable plate and the base plate. The circular hole is provided in the center of the base. The central column or the heat insulating casing is mounted on the base through the circular hole. The fixing plate, the detachable plate, the base plate and the central column or the heat insulating casing form a cavity for preparing the core and the cement sheath. During use, the device is placed in a low temperature context, and then the frozen soil core with a hollow cylinder can be artificially fabricated. Further, the heat insulating casing holder is placed, and the cement is added to simulate the state of the cement sheath consolidation under the actual strata conditions.

Abstract: The present disclosure discloses a core-shell structured NiSe2@NC electrocatalytic material having a general formula of NiSe2@NC. The present disclosure also provides a preparation method and use of the catalytic material. In the present disclosure, hydrazine hydrate is used as a reducing agent, selenium powders are used as a source of selenium, and a metal-organic framework (MOF) is used as a precursor. Selective selenization of mixed-linker MOFs based on mixed ligands is carried out through a hydrothermal reaction. Then, a series of adjustable N-doped carbon-coated NiSe2 nano-octahedrons are prepared through a one-step calcination reaction. By adjusting the types of mixed ligands in the MOF, carbon-coated nickel diselenide composites doped with different pyridinic-N contents can be obtained. Corresponding electrochemical tests prove that, the electrocatalytic activity has a strong correlation with the content of pyridinic-N.

Abstract: A pH sensitive water-absorbent resin suitable for oil well cement slurry and an application thereof are provided. The pH sensitive water-absorbent resin includes distilled water, a monomer, a mixed auxiliary agent, a crosslinking agent and an initiator, the amount of the monomer is 30% to 100% of the mass of the distilled water, the amount of the mixed auxiliary agent is 16% to 67% of the mass of the monomer, the amount of the crosslinking agent is 0.2% to 1% of the mass of the monomer, and the amount of the initiator is 0.4 to 1% of the mass of the monomer.

Abstract: The present invention relates to the field of natural gas production, and discloses a well structure for natural gas hydrate production, which comprises: a natural gas production well (12); an injection well (4) capable of extending into a geothermal reservoir and injecting a heat-carrying fluid; a high curvature connecting well (7), the inlet end of the high curvature connecting well (7) is connected to the outlet end of the injection well (4); a hydrate production horizontal well (10), which may be arranged in a shallow hydrate reservoir (9), the high curvature connecting well (7) and the hydrate production horizontal well (10) are connected by an ascending well section (8), and connected with the natural gas production well (12). With the above technical scheme, the high curvature connected well connecting the horizontal well and the vertical well can be located in the bottom layer below the hydrate reservoir, enhancing the stability and production efficiency of the gas hydrate production well.

Abstract: The present disclosure provides a multi-path combined high-low voltage plasma rock-breaking drill bit, drill bit apparatus and drilling method. The multi-path combined high-low voltage plasma rock-breaking drill bit comprises: a drill bit body, insulators, plasma generators, drilling fluid outlets, plasma integrated pipelines, a drilling fluid pipe; wherein a plurality of plasma generators are distributed on the same drill bit body; the axis of the plasma generator and the axis of the drill bit body form a certain included angle; each of the plasma generators is independently connected to the ground through its respective plasma integrated pipeline and operates independently; and drilling fluid flows out of the drilling fluid outlets, takes away the heat generated by the operation of the plasma generators, thereby cooling the plasma generators.

Abstract: Disclosed belongs to the technical field of oil and gas field development engineering, and particularly relates to a super heavy oil development method for strengthening an SAGD steam chamber to break through a low physical property reservoir. The super heavy oil development method for strengthening the SAGD steam chamber to break through the low physical property reservoir includes the following steps: (1) selection of a developed oil reservoir; (2) well distribution; (3) steam chamber forming; (4) steam chamber expansion; (5) steam chamber strengthening. The method may enhance the ability of the steam chamber to break through the low physical property reservoir, enlarge the development height of the steam chamber, and further improve the SAGD development effect of super heavy oil.

Abstract: The present disclosure provides a preparation method of an environment-friendly high-temperature resistant water-based drilling fluid plugging anti-sloughing agent, the preparation method comprises the following steps: mixing and emulsifying a styrene monomer, an acrylic monomer and an emulsifier MS-1 aqueous solution to prepare a pre-polymerization emulsion; dispersing hydrophilic monomer, cationic monomer and an emulsifier MS-1 in water, adjusting the pH to be within a range of 6.5-8.

Abstract: Provided is a carbon dioxide fluidity control device comprising, a sample preparation tank, a high-pressure stirring unit, a reciprocating plunger pump and a booster pump, wherein the stirring unit comprises one or more high-pressure stirring tanks, each provided with an atomizing spray probe and a piston, wherein a discharge port of the sample preparation tank is connected to the atomizing spray probe via a plunger pump, which is connected to the piston to push the piston to reciprocate; the booster pump is connected to the high-pressure stirring tanks to provide supercritical carbon dioxide to the high-pressure stirring tank; and a discharge port of the high-pressure stirring tanks is connected to an oilfield well group. Provided is a carbon dioxide fluidity control method using the device, comprising mixing surfactants and nanoparticles with heated carbon dioxide, and injecting a microemulsion of supercritical carbon dioxide and nano-silicon dioxide into an oilfield well group.

Abstract: A filtrate reducer for temperature-resistant calcium-resistant water-based drilling fluid used in oil and gas reservoir protection, a drilling fluid, and uses of the filtrate reducer and the drilling fluid are described. The filtrate reducer contains structural units represented by formulas (1), (2), and (3) herein. The water-based drilling fluid contains the filtrate reducer, and exhibits good inhibitive, rheological, filtrate reducing, and reservoir protection performance when it is applied in the drilling process in a high-temperature high-calcium deep salt-gypsum formation.

Abstract: A temperature-resistant calcium-resistant water-based drilling fluid for oil and gas reservoir protection and a use thereof is provided. The water-based drilling fluid contains a filtrate reducer and a plugging agent, wherein the filtrate reducer is a copolymer that contains structural units represented by formula (1), structural units represented by formula (2), and structural units represented by formula (3), wherein, the mass ratio of the structural units represented by formula (1) to the structural units represented by formula (2) to the structural units represented by formula (3) is (0.1-0.2):1:(0.05-0.1), and the number-average molecular weight of the copolymer is 10,000-100,000, the plugging agent is acrylamide-diallyldimethylammonium chloride copolymer modified graphene.

Abstract: A simulation test system for gas extraction from a tectonically-deformed coal seam in-situ by depressurizing a horizontal well cavity. A coal series stratum structure reconstruction and similar material simulation subsystem simulates a tectonically-deformed coal reservoir. A horizontal well drilling and reaming simulation subsystem constructs a U-shaped well in which a horizontal well adjoins a vertical well, and performs a reaming process on a horizontal section thereof. A horizontal well hole-collapse cavity-construction depressurization excitation simulation subsystem performs pressure-pulse excitation and stress release on the horizontal well, and hydraulically displaces a coal-liquid-gas mixture such that the mixture is conveyed towards a vertical well section. A product lifting simulation subsystem further pulverizes the coal and lifts the mixture. A gas-liquid-solid separation simulation subsystem separates the coal, liquid and gas.

Abstract: An active control method and system for wellbore pressure in open-cycle drilling in marine natural gas hydrates. The system comprises a drilling system, a drilling fluid injection system, and a data processing system for conducting the drilling operation.

Abstract: A simulation test method for gas extraction from a tectonically-deformed coal seam in-situ by depressurizing a horizontal well cavity. A coal series stratum structure reconstruction and similar material simulation subsystem simulates a tectonically-deformed coal reservoir. A horizontal well drilling and reaming simulation subsystem constructs a U-shaped well in which a horizontal well adjoins a vertical well, and performs a reaming process on a horizontal section thereof. A horizontal well hole-collapse cavity-construction depressurization excitation simulation subsystem performs pressure-pulse excitation and stress release on the horizontal well, and hydraulically displaces a coal-liquid-gas mixture such that the mixture is conveyed towards a vertical well section. A product lifting simulation subsystem further pulverizes the coal and lifts the mixture. A gas-liquid-solid separation simulation subsystem separates the coal, liquid and gas.

Abstract: The present disclosure belongs to the field of petroleum engineering, in particular to a fully-electrically driven downhole safety valve. The fully-electrically driven downhole safety valve comprises a downhole safety valve mechanism and a downhole safety valve control system; wherein the downhole safety valve mechanism includes an electronic cabin module, a transmission control module, a motion conversion module, a magnetic coupling and spring module. and a valve module; the downhole safety valve control system includes a downhole comprehensive unit and an uphole comprehensive unit.

Abstract: A drilling casing includes a casing wall and several sand control apparatuses disposed on the casing wall in a spacing. Each sand control apparatus includes a sand control net, a sealing steel sheet and a sealing rubber plug. A plurality of mutually-paralleled sand control meshes are disposed on the sand control net. The sand control mesh exactly faces the sealing steel sheet. The sand control net is connected with the sealing steel sheet through a steel pin. Further, a method of performing fast drilling and completion of a large-borehole multilateral well by the drilling casing includes forming a main borehole by drilling to a destination well depth at one time with a large-size drill bit, drilling a lateral borehole in a natural gas hydrate reservoir by using the drilling casing, and taking out the drill bit for completion. The method is applicable to various natural gas hydrate extraction manners.

Abstract: The present disclosure discloses a fluorescent dispersed particle gel, a fluorescent gel, a fluorescent modified polyacrylamide composite, and a preparation method and use thereof.

Abstract: The embodiment of the present invention provides a semi-supervised automatic marking method for spartina alterniflora in a hyperspectral image. According to the semi-supervised automatic marking method for spartina alterniflora in a hyperspectral image provided by the present invention, based on the dimensionality reduction on 108-dimensional data of 18 wave bands, unsupervised clustering is performed by the fast clustering algorithm based on the local density, and then the clustering result is matched with a marked spartina alterniflora data set, so that completely automatic marking of the data is realized, and automatic marking for spartina alterniflora is realized. The embodiment of the present invention also provides a semi-supervised automatic marking device for spartina alterniflora in a hyperspectral image. Through the technical scheme provided by the embodiment of the present invention, recognition and marking for spartina alterniflora can be realized accurately and effectively.

Abstract: The application relates to the technical field of oil and gas field development, and discloses a correction method and system for a permeability model considering gas hydrate distribution, and a method and system for determining the permeability of the hydrate-bearing porous medium.

Abstract: A method and system for determining contact angles of porous media, including: in a displacement simulation experiment, injecting a displacement fluid into a actual core sample, and performing computed tomography scanning on the core to determine three-dimensional images at different oil displacing time points; segmenting different phases of the three-dimensional images to obtain segmented three-dimensional images; marking a contact line between different phases according to the segmented three-dimensional images, where the phases are underground fluids or displacement fluids and a rock matrix in the displacement simulation experiment; and determining a contact angle of the porous media at different 3D positions at different time points according to the contact line. The method and system provided can obtain the dynamic changing process of the contact angle at different 3D positions in the core at different displacement time points, reflect the wettability of the real reservoir environment more accurately.