Abstract: The present disclosure relates to a method for evaluating a temporary plugging effect of fracturing in a low-permeability oil-gas reservoir based on monitoring pressure. The method comprises: calculating a wellbore friction resistance along a way from a wellhead to a target fracturing segment; calculating, based on a wellhead pressure monitored at the wellhead in real time, a wellbore pressure at the target fracturing segment; calculating a fluid pressure at a crack opening of each perforation cluster; calculating a perforation friction resistance coefficient of each perforation cluster; calculating a fracturing fluid instantaneous displacement of each perforation cluster; calculating, based on the fracturing fluid instantaneous displacement of each perforation cluster, a variation coefficient of a fracturing fluid displacement distribution after a fracturing construction is completed; and evaluating the temporary plugging effect of fracturing based on the variation coefficient.

Abstract: A calculation method for fractal dimensions of shale pores includes steps as follows. S1: multiple shale samples from a target stratum of a study area are obtained, parameter values of geological parameters of each of the multiple shale samples are obtained, followed by dividing the multiple shale samples into target shale samples and experimental shale samples. S2: PCA is performed on the parameter values to obtain principal components representing a variation of the geological parameters. fractal dimensions are calculated based on an existing fractal dimension calculation method. S3: the principal components are used as independent variables and the fractal dimensions are used as dependent variables, followed by performing regression analysis to obtain a quantitative calculation model. S4: the fractal dimensions of the target shale sample are calculated according to the parameter values and the quantitative calculation model for the fractal dimension based on the parameter values.

Abstract: Disclosed is a fracture plugging simulation experimental device and an experimental method thereof. The device comprises a simulated wellbore, a simulated formation, a simulated fracture, a plurality of pressure sensors and vales, a mixing barrel, a liquid injection port and a pressurization port, a liquid collection tank, a plugging fluid storage tank, a heating device, etc. The method comprises: loading the simulated formation with the simulated fracture in the simulated wellbore, closing the second valve and turning on the mixing device, injecting a lost circulation material into the mixing barrel, closing the liquid injection port and turning on the heating device and pressurizing, stopping pressurizing and opening the second valve to establish a plugging process, turning on the plunger pump to continue pressurizing, and collecting a fluid pressure change of the simulated fracture in the plugging process; and calculating a pressure-bearing capacity of plugged fracture.

Abstract: The embodiments of the present disclosure provide a method for diagnosing control effectiveness of a fracture height in hydraulic fracturing by combining monitoring a pressure signal, comprising: obtaining engineering data and geological data; calculating a fracture slit fluid pressure, a double-logarithmic slope of the fracture slit fluid pressure, and a bedding fracture pressure; updating a growth time of the fracture height and a reference pressure based on the fracture height in hydraulic fracturing; based on determining whether a fracturing construction operation ends, updating the cumulative fracturing time or calculating a ratio of the growth time of the fracture height to the total time of hydraulic fracturing.

Abstract: Disclosed is a system for optimizing a particle size distribution of a lost circulation material. The system comprises a data acquisition module, a communication module, an experimental module, a particle size distribution optimization module, and a plugging and filling module. The data acquisition module is configured to obtain a target feature particle size. The experimental module is configured to obtain the target feature particle size, and set a plurality of experimental schemes for fracture plugging; conduct fracture plugging experiments to obtain experimental results; evaluate a plurality of fracture plugging effects of each of the plurality of experimental schemes. The particle size distribution optimization module is configured to obtain the plurality of fracture plugging effects, determine a particle size distribution rule, and obtain optimized particle size distribution data by optimizing the particle size distribution of the lost circulation material.

Abstract: A device for preventing abrupt blockage in a blooie line of gas drilling includes a sand-storing tank body, which is connected to a rotating blowout preventer through a guiding tube, and a guiding three-way joint is set between the guiding tube and the sand-storing tank body and connected to the blooie line by a vertical guiding tube; the sand-storing tank body is connected to the blooie line by means of a gas discharge tube; a flap plate assembly is arranged at the position fronting straight onto the guiding three-way joint inside the sand-storing tank body, and configured to control the rock particles in the guiding tube to enter the sand-storing tank body, preventing blockage in the blooie line.

Abstract: Disclosed is a fracture plugging simulation experimental device and an experimental method thereof. The device comprises a simulated wellbore, a simulated formation, a simulated fracture, a plurality of pressure sensors and vales, a mixing barrel, a liquid injection port and a pressurization port, a liquid collection tank, a plugging fluid storage tank, a heating device, etc. The method comprises: loading the simulated formation with the simulated fracture in the simulated wellbore, closing the second valve and turning on the mixing device, injecting a lost circulation material into the mixing barrel, closing the liquid injection port and turning on the heating device and pressurizing, stopping pressurizing and opening the second valve to establish a plugging process, turning on the plunger pump to continue pressurizing, and collecting a fluid pressure change of the simulated fracture in the plugging process; and calculating a pressure-bearing capacity of plugged fracture.

Abstract: Methods and systems for determining a well shut-in pressure of oil and gas well drilling are provided. The method comprises: obtaining, by a first processor, a basic parameter of a target oil and gas well, the basic parameter including at least one of a wellbore structure parameter, a well drilling fluid performance parameter, or a casing string parameter; obtaining, by the first processor, a pressure calculation model; and determining, by the first processor, a maximum well shut-in pressure during well drilling of the target oil and gas well based on the pressure calculation model and the basic parameter.

Abstract: Disclosed is a system for optimizing a particle size distribution of a lost circulation material. The system comprises a data acquisition module, a communication module, an experimental module, a particle size distribution optimization module, and a plugging and filling module. The data acquisition module is configured to obtain a target feature particle size. The experimental module is configured to obtain the target feature particle size, and set a plurality of experimental schemes for fracture plugging; conduct fracture plugging experiments to obtain experimental results; evaluate a plurality of fracture plugging effects of each of the plurality of experimental schemes. The particle size distribution optimization module is configured to obtain the plurality of fracture plugging effects, determine a particle size distribution rule, and obtain optimized particle size distribution data by optimizing the particle size distribution of the lost circulation material.

Abstract: The present disclosure relates to a method for predicting an amount of water-sealed gas in a high-sulfur water-bearing gas reservoir. The method solves the problem that no method has yet been proposed for predicting the amount of water-sealed gas in a high-sulfur water-bearing gas reservoir. According to the technical solution, the method includes: considering that the volume of the gas reservoir does not change during the production of the constant-volume gas reservoir, deriving, based on a material balance method, a material balance equation of the high-sulfur water-bearing gas reservoir in consideration of water-sealed gas and water-soluble gas, solving and drawing a chart of water-sealed gas in the high-sulfur water-bearing gas reservoir by an iterative algorithm, obtaining a recovery factor of the high-sulfur water-bearing gas reservoir in consideration of water-sealed gas and water-soluble gas, and further obtaining the amount of water-seal gas in the high-sulfur water-bearing gas reservoir.

Abstract: Disclosed is a method for determining a reasonable soaking time of a shale oil/gas well, implementing testing and experimentation using a device for testing a reasonable soaking time of a shale oil/gas well.

Abstract: The present disclosure provides a high-temperature-resistant deep penetration molecular membrane acid copolymer and a preparation method thereof. The copolymer is formed by polymerizing four raw monomers including 2-acrylamido-2-methylpropanesulphonic acid, vinyl phosphonic acid, alkyl dimethylallyl ammonium chloride, and perfluoropolyether acrylate. The method comprises: S1: mixing and stirring solvent oil, an emulsifier, the alkyl dimethyl allyl ammonium chloride, and the perfluoropolyether acrylate to be dispersed homogeneously to obtain an oil phase; S2: mixing and stirring the 2-acrylamido-2-methylpropanesulphonic acid, the vinyl phosphonic acid, a complexing agent, and distilled water, and adjusting pH to obtain an aqueous phase; S3: slowly dropwise adding the aqueous phase to the oil phase; and S4: introducing nitrogen into the water-in-oil emulsion to remove oxygen, then adding an initiator and carrying out a heating polymerization reaction to obtain copolymer emulsion (i.e.

Abstract: The embodiments of the present disclosure disclose an evaluation apparatus and a method for seal integrity of a wellbore in a full life cycle. The apparatus may include an oil pipe temperature and pressure simulation assembly, an oil casing annular temperature and pressure simulation assembly, a formation confining pressure simulation assembly, a casing-cement sheath-formation combination preparation assembly, a blowby characteristic detection assembly, and a monitoring system. The present disclosure may crustal stress quickly complete scanning of cement slurry system and maintenance and preparation of casing-cement sheath-formation combination, intelligent monitor blowby pressure of cement sheath in real time, test the critical blowby pressure curve of cement sheath of oil and gas wells under various production conditions throughout the life cycle for evaluating the seal integrity of wellbore, and provide technical support for the formulation of wellbore safeguard measures.

Abstract: The present invention discloses a double-crosslinked thermal phase transition gel temporary plugging agent and an application thereof, and relates to the technical field of oil and gas field development. The gel temporary plugging agent comprises the following components in percentage by weight: 5.8-18.3% of acrylic acid, 2.8-6.5% of 2-acrylamide-2-methylpropanesulfonic acid, 2.8-7.0% of hydroxyethyl acrylate, 0.2-1.0% of a degradable crosslinking agent, 0.4-1.2% of borax or boric acid, 0.2-0.8% of a high-temperature initiator, 2.6-4.5% of palygorskite attapulgite, 1.5-3.1% of a urea-formaldehyde resin, and the balance of water, wherein the gel temporary plugging agent is formed by underground gelation. The gel temporary plugging agent is applied to oil and gas reservoirs with a temperature of 100-150° C., can automatically be subjected to gelation and degradation, and has a low filtration loss before gelation.

Abstract: The present disclosure provides a method for an accurate well-seismic tie based on stepwise matching and optimization, including: determining target seismic data as a seismic trace near well and performing first data processing on the target seismic data; performing second data processing on the logging information to determine a reflection coefficient sequence; extracting seismic wavelets, convoluting the seismic wavelets with the reflection coefficient sequence, determining a synthetic seismic record of the target calibration object in a time domain, performing third data processing on the synthetic seismic record; determining a correlation between the seismic trace near well and the synthetic seismic record, determining a global time shift between the synthetic seismic record and the seismic trace near well, performing a preliminary alignment on the synthetic seismic record; and calculating a local time shift between the seismic trace near well and the synthetic seismic record and accurately calibrating th

Abstract: A method for determining a phase-state type and saturation of a fluid by an NMR technology includes putting a core to be measured to an NMR phase-state testing device, injecting a heavy water solution from both ends of a gripper at the same time until the core reaches the formation pressure, and stopping; scanning the core to obtain a two-dimensional NMR map, and determining whether the core contains a gas phase; reducing the temperature of the gripper, and collecting an oil phase volume, a gas phase volume and a water phase volume discharged from the core; purge the pipelines out with nitrogen, collecting a water phase volume and an oil phase volume in the pipelines; performing dry distillation on the core to obtain an oil phase volume and a water phase volume; and obtaining the saturations of various phases according to the fluid volumes of multiple phases in the core.

Abstract: A method for predicting a risk of early screen-out in a near-well zone based on distributed fiber acoustic sensing (DAS) is provided.

Abstract: The present invention discloses an active intelligent wellbore pressure control system, which includes a ground multi-parameter online monitoring system (86), a rotary blowout preventer (1), a wellhead back pressure compensation manifold, an automatic plugging material filling device (62), a drilling device, an MPD intelligent control system (87), a remote monitoring and control system (88), and a high-precision hydraulic calculation system (105).

Abstract: The present invention discloses a CO2 responsive core-shell multi-stage swelling microsphere and a preparation method thereof. The preparation method comprises the following steps: adding a styrene monomer into a sodium dodecyl sulfate solution for emulsion polymerization to obtain a spherical polystyrene solution, taking azobisisobutyronitrile and ethylene glycol for Pinner reaction to obtain an azo compound with hydroxyl functional groups at two ends, taking the azo compound with the hydroxyl functional groups at two ends as a raw material for Schotten-Baumann reaction with methacryloyl chloride to obtain BPAB, adding the BPAB into the spherical polystyrene solution to prepare an active polystyrene core solution, and dissolving the active polystyrene core solution, acrylamide, a CO2 responsive monomer, a CO2 responsive cross-linking agent and a stable cross-linking agent into water to obtain a target product.

Abstract: The present invention relates to a low-shrinkage and high-strength plant-based resinous blocking agent and preparation method thereof, and belongs to the technical field of oilfield development. The resinous blocking agent consists of the following substances according to weight parts: 37.2˜47.8 parts of epoxy plant oil, 19.8˜37.2 parts of benzoxazine, 22.9˜31.6 parts of curing agents, 0.8˜1.8 parts of initiators, 1.2˜1.8 parts of toughening agents, 0.5˜1.2 parts of reinforcing agents, wherein the sum of the weight parts of the above substances is 100 parts, the epoxy plant oil is obtained through epoxidation on unsaturated carbon-carbon double bonds in a molecule of dehydrated plant oil; the benzoxazine is synthesized from long-chain diamine, monohydric plant phenol and paraformaldehyde.