521 results about "Field development" patented technology

The invention relates to the technical field of oil and gas field development, and discloses an ultra-large type true triaxial hydraulic fracturing fracture evolution path prediction method and system.The prediction method comprises the steps that a coupling geomechanical model integrating microscopic, macroscopic and wellbore flow scales is constructed; initializing the model and performing crack initial expansion simulation; collecting construction data in real time, and dynamically optimizing model parameters through a data assimilation algorithm; performing fracture evolution advanced prediction by using the updated model; and generating an optimization decision based on the prediction result and feeding back to the construction site. According to the method, fusion of a multi-scale physical mechanism and real-time dynamic prediction is realized, and accurate prediction and active control can be performed on crack expansion under the ultra-large true triaxial condition.

The invention discloses an intelligent optimization method for a multi-type well seam joint control fine injection-production mode, and relates to the technical field of oil-gas field development. The method comprises the following steps: setting a well seam joint control fine injection-production mode, establishing an oil reservoir numerical simulation model in oil reservoir numerical simulation software, obtaining multiple groups of oil reservoir injection-production schemes based on a Latin hypercube sampling method, performing simulation according to each group of oil reservoir injection-production schemes by utilizing the oil reservoir numerical simulation model, generating multiple pieces of sample data, and establishing a sample database; a deep learning agent model is established, after the sample database is utilized to train and train the deep learning agent model, a particle swarm optimization algorithm is adopted to carry out single-target pre-search global optimization to obtain a preferred reference strategy, a reinforcement learning dynamic decision model is established, and a reinforcement learning agent is obtained through training based on a PPO near-end strategy optimization algorithm; and the optimal injection-production development scheme of the oil reservoir is obtained by utilizing the reinforcement learning agent, so that rapid optimization and decision support of the oil reservoir injection-production scheme in a new multi-type well seam joint control mode are realized.

The invention relates to the technical field of oil and gas field development, in particular to a gas drive front description method based on a multi-modal fusion deep learning model. The method comprises the steps of collecting multi-modal data, and constructing a multi-modal comprehensive database; performing data preprocessing and cleaning on the multi-modal comprehensive database; constructing a multi-modal fusion deep learning model; carrying out training and hyper-parameter optimization on the multi-modal fusion deep learning model; inputting real-time data into the trained model, and outputting a leading edge prediction result; and according to an output prediction result, new data meeting requirements are added into a multi-modal comprehensive database, model incremental training is triggered, and parameters are updated to adapt to dynamic changes of the oil reservoir. And rapid, accurate and global dynamic prediction of the gas-driven front is realized.

The invention provides a method and a device for measuring the solid-phase deposition amount of crude oil under high-temperature and high-pressure conditions, and relates to the technical field of oil-gas field development. Under the reservoir temperature and pressure of a target oil reservoir, ground degassed crude oil, associated gas and an on-site solid-phase sediment sample are mixed and dissolved; an in-situ crude oil sample capable of truly reflecting in-situ crude oil components is prepared; then, reducing the pressure to a target pressure point in a stepped manner at a constant temperature, and delimiting a deposition monitoring area; spectral image data of the area is obtained, spectral reflection reference rate is analyzed and calculated pixel by pixel, and a spectral distribution matrix is constructed; judging whether the solid-phase deposition reaches balance or not by calculating a space consistency index and a time convergence index of the matrix; finally, the solid-phase deposition amount is calculated after deposition equilibrium; according to the method, the problem of solid-phase deposition measurement distortion under the ultrahigh-pressure oil reservoir condition is solved, and interference-free, real-time monitoring and quantitative analysis in the deposition process are achieved.

The invention relates to the technical field of oil and gas field development, in particular to an ultra-deep gas well production string multi-mode leakage simulation experiment device and method. According to the technical scheme, the outer side of a shaft temperature and pressure coupling simulation system is connected with a reservoir gas supply simulation system, the middle of the shaft temperature and pressure coupling simulation system is provided with a multi-mode leakage simulation assembly, the lower end of a production oil pipe is connected with a reservoir-shaft coupling connector, and the upper portion of one side of a layered sand filling seepage tank of the reservoir gas supply simulation system is connected with a confining pressure loading unit through a pipeline; the lower portion of the layered sand filling seepage tank is connected with a reservoir fluid supply unit, and the outlet end of the layered sand filling seepage tank is connected with a reservoir-shaft coupling connector through a pipeline. The experimental device has the beneficial effects that the experimental device for coupling the reservoir and the shaft is constructed, and the multi-mode leakage simulation assembly is adopted to realize body perforation leakage simulation and screw thread sealing failure simulation, so that the simulation of the ultra-deep gas well under complex working conditions is realized, and a scientific basis and a technical support are provided for leakage prevention and control of a production string of the ultra-deep gas well.

The invention belongs to the technical field of oil and gas field development, and discloses a fractured gas reservoir fracturing crack complexity evaluation method and related device.The method comprises the steps that stratum data and construction data of an earlier-stage reconstructed well in a work area are collected; the G function pressure filtration occurrence frequency, the well bottom net pressure fluctuation frequency and average fluctuation amplitude of the prepad fluid stage and the fracture net extension duration proportion are calculated respectively; calculating correlation coefficients between the G function pressure filtration occurrence frequency, the bottom hole net pressure fluctuation frequency and average fluctuation amplitude of the prepad fluid stage, and the fracture network extension duration ratio and the transformation volume; and calculating a crack complexity index based on the correlation coefficient. According to the method, calculation is carried out according to on-site construction parameters, the complexity of cracks formed in the construction process can be quantitatively described conveniently, construction parameter optimization and production system optimization can be effectively guided, long-term stable production of gas reservoirs is guaranteed, and therefore large economic benefits are obtained.

The invention discloses a displacement potential energy gradient oriented injection-production reconstruction optimization method between fracturing segments, and relates to the technical field of oil and gas field development. The method comprises the following steps: firstly, establishing an oil reservoir three-dimensional numerical model according to oil reservoir interpretation data, simulating in an oil reservoir numerical simulator by using the oil reservoir three-dimensional numerical model to obtain a global pressure field and a fluid flow velocity change condition in the oil reservoir, constructing a fluid potential field model, and determining potential energy gradients among injection-production units; constructing an objective function and setting constraint conditions by taking the most balanced potential energy gradient distribution among all injection and production units in the fluid potential field model as an optimization objective, solving the objective function based on a particle swarm algorithm, and optimizing the horizontal well multi-stage fracturing inter-section injection and production scheme to obtain the optimal horizontal well multi-stage fracturing inter-section injection and production scheme. The control device is used for controlling the injection-production process device between the multistage seam sections of the horizontal well, quantitative characterization and active control of an oil reservoir fluid potential field are achieved, and a basis is provided for improving the injected fluid sweep volume and the crude oil recovery rate of an oil reservoir.

The invention discloses a CO2 well flooding oil casing pressure intelligent control and anti-freezing and anti-blocking system, and relates to the technical field of oil and gas field development engineering.The CO2 well flooding oil casing pressure intelligent control and anti-freezing and anti-blocking system comprises the steps that a controller starts a self-checking program, loads a preset target pressure value, a preset temperature early warning threshold value and a preset ice blocking critical temperature parameter, completes initial configuration, and sends the initial configuration to the controller; zero calibration and precision verification are carried out on the front-end pressure sensor, the rear-end pressure sensor and the temperature sensor, front-end pressure data, rear-end pressure data and temperature data are collected, data filtering and abnormal value removing processing are carried out, and the real-time temperature data and CO2 physical property parameters are obtained. According to the invention, hardware self-inspection and sensor precision calibration are realized through the controller initialization module, the data acquisition module completes multi-source data synchronous acquisition and filtering processing, and the dynamic risk assessment module based on an improved Span-Wagner equation and a fuzzy logic algorithm can accurately calculate a CO2 phase change critical point and output a quantitative risk index. The problems of energy waste and untimely freezing and blocking prevention caused by a traditional fixed threshold value method are solved.

The invention belongs to the technical field of oil and gas field development engineering and multiphase flow numerical simulation, and relates to a rapid prediction method for gas-liquid two-phase flow key flow parameters of a horizontal gas well. Constructing the mixed momentum equation, the mass conservation equation and the drift velocity constitutive relation into a partial differential equation residual group; secondly, constructing a physical information Fourier operator network architecture, and learning integral operator mapping from working condition parameters to flow field distribution in a frequency domain by using a lifting layer, a Fourier layer and a projection layer; and finally, calculating a partial derivative of an output variable relative to a space-time coordinate by utilizing an automatic differential technology, and constructing a loss function fusing a data error and a physical PDE residual error to carry out model training. According to the method, millisecond-level accurate prediction of the pressure, the liquid holdup and the flow velocity field of the whole wellbore is achieved, and the problems that traditional numerical simulation calculation is long in time consumption, the real-time monitoring requirement is difficult to meet, and a pure data driving model lacks physical consistency are solved.

The invention discloses an oil reservoir history fitting method based on graph lasso and set smooth multi-data assimilation, and relates to the technical field of oil and gas field development. The method comprises the following steps: firstly, acquiring to-be-optimized model parameters and observation data of a target oil reservoir, constructing an observation error covariance matrix and initializing a model parameter set, performing numerical simulation by utilizing an oil reservoir numerical simulator to obtain prediction data, constructing a joint state matrix, performing dimensionless standardization processing on the joint state matrix to obtain an empirical correlation coefficient matrix, and then, performing optimization on the joint state matrix. And executing a graph lasso algorithm combined with an extended Bayesian information criterion to obtain an optimal dimensionless sparse precision matrix, extracting correlation coefficient sub-blocks required by Kalman updating from the optimal dimensionless sparse precision matrix based on a Scherr's theorem, obtaining a robust data auto-covariance matrix through a reverse reduction physical quantity outline, calculating Kalman gain in combination with an observation error covariance matrix, and calculating a Kalman filter. And the model parameter set is updated until the preset condition is met, the reservoir history fitting model parameter set is output, and the stability and precision of reservoir automatic history fitting are improved.

The invention discloses an oil and gas shaft multiphase flow simulator MphaseSim modeling method and a PINN solving method, and relates to the technical field of oil and gas field exploitation, and the method comprises the following steps: pre-calibrating a modeling strategy, including calibrating gas-liquid two-phase flow, and calculating the average flow velocity according to the section occupied by the gas-liquid two-phase flow; mass transfer can occur between the calibrated gas and liquid phases, but the gas and liquid phases are always in a thermodynamic equilibrium state; in calibration steady-state analysis, the mass flow of any section of the shaft is equal, and the liquid holdup is calculated through a drift-assisted equation. According to the method, on the basis of a mass-momentum-energy coupling mathematical model, the SRK state equation and the drift flow model are combined, the phase change characteristics, momentum transfer and energy conversion rules of the gas phase and the liquid phase can be accurately represented, the model sealing performance is good, and the physical significance is clear; and the device can be stably applied to different types of oil and gas well scenes such as gas wells, deep oil wells and electric submersible pump wells, has no obvious numerical value divergence problem in long shaft flow simulation, and can effectively reflect the real production state of the shaft.

The invention belongs to the technical field of oil and gas field development engineering, and particularly relates to a construction method of an emulsion generation kinetic model. The method is based on a micro-fluidic experiment, comprehensively considers seven factors of pore throat radius, pore throat form, pore throat coordination number, displacement environment temperature, surfactant concentration, injection speed and crude oil viscosity, and determines an undetermined coefficient of a function by utilizing a least square method through single factor analysis and orthogonal experiment scheme design; therefore, the functional relationship among the pore throat radius, the pore throat form, the pore throat coordination number, the displacement environment temperature, the surfactant concentration, the injection speed, the crude oil viscosity and the emulsion generation rate and the generation radius is defined, and an emulsion generation kinetic model is constructed, so that an emulsion generation theoretical system under the multi-factor coupling effect is perfected; and reference is provided for other similar chemical flooding.

The invention discloses a design optimization method and device for an injection-production well pattern, relates to the technical field of well pattern deployment optimization in oil and gas field development engineering, and aims to automatically optimize a well position according to three-dimensional distribution of remaining oil so as to improve the recovery ratio. According to the main technical scheme, the method comprises the steps of determining a remaining oil saturation field of a designated area according to a three-dimensional geologic model; identifying a remaining oil enrichment area based on the spatial form parameters and connectivity indexes in the remaining oil saturation field; according to the remaining oil reserves, the displacement efficiency and the inter-well pressure and flow of all the remaining oil enrichment areas, the mining potential index and the mining risk level of all the remaining oil enrichment areas are calculated; and taking recovery efficiency maximization and productivity equalization as optimization objectives, taking the mining potential index as a recovery efficiency weight factor, taking the mining risk level as a risk constraint condition, and adopting a multi-objective optimization algorithm to generate a target injection-production well pattern.

The invention discloses a method, a system, equipment and a medium for detecting an oil-water two-phase relative permeability curve, and belongs to the technical field of oil-gas field development technologies. The detection method of the oil-water two-phase relative permeability curve comprises the following steps: washing oil and drying a rock core sample, vacuumizing the rock core sample, and injecting formation water into the rock core sample, so that the rock core sample reaches a saturated water state; injecting crude oil into the core sample at a preset oil reservoir temperature to enable the core sample to reach a saturated oil state; performing water-displacing oil operation on the rock core sample at a preset flow rate, and scanning the rock core sample at a plurality of scanning nodes by using a CT (Computed Tomography) scanning device; oil saturation and water saturation are calculated according to an actually measured rock core CT value, and parameter fitting is performed on the Corey model according to the oil saturation and the water saturation to obtain an oil-water two-phase relative permeability curve. The method can accurately detect the oil-water two-phase relative permeability curve of the rock core.

The application belongs to the technical field of oil and gas field development, and particularly relates to a temperature-resistant and salt-resistant foaming agent for drilling and a synthesis method thereof. The synthesis method is as follows: diphenylamine-4-sodium sulfonate, isopropyl alcohol and 1,3-dibromopropane are added into a four-necked flask, stirred, heated and refluxed to obtain a mixed solution; 90-95wt% of isopropyl alcohol in the mixed solution is distilled off under reduced pressure, distilled water is added, and the whole is transferred into a separatory funnel, fully shaken, separated, and a small amount of oil phase is discarded; the pH is adjusted to 2-3, a precipitate is separated out, suction filtration is performed, and an intermediate is obtained; the intermediate is transferred into a four-necked flask with isopropyl alcohol, sodium bromoethyl sulfonate is added, the pH is adjusted to 7-8, and the product solution is obtained by heating and refluxing; the product is obtained by vacuum distillation, recrystallization and drying. The foaming agent for drilling has the advantages of good temperature resistance, salt resistance and salinity resistance.

This invention relates to the field of oil and gas field development, and discloses a full-scale DAS (Digital Angiography and Semiconductor) device and method for monitoring the integrity of hydrate development wellbore. The device includes a formation simulation device, a wellbore simulation device, and a monitoring device. The formation simulation device comprises a temperature control system, a pressure control system, and a simulated formation. The temperature control system, pressure control system, and simulated formation are connected to the wellbore simulation device. The temperature control system and pressure control system are used to simulate the actual temperature and pressure of the hydrate formation. The simulated formation is prepared according to the actual mineral composition and grain size distribution of the hydrate reservoir. The monitoring device is located outside the wellbore simulation device and works in conjunction with the formation simulation device to perform real-time, full-well-section monitoring during hydrate development. This invention can simulate real wellbore conditions and perform real-time, continuous monitoring of the entire wellbore to meet the needs of dynamic downhole monitoring in actual production.

The application discloses a kind of prediction methods for determining recovery ratio of stratified gas reservoir under different well interference conditions, and belongs to the technical field of oil and gas field development.It includes collecting and arranging gas reservoir basic data;Establish well control area under different well interference, and, based on the existing production pressure difference condition gas reservoir waste gas pressure determination formula;Finally, consider the determination of stratified gas reservoir recovery ratio of well control area.The present application determines the accurate gas reservoir abandonment condition by definite integral principle under the maximum production pressure difference, overcomes the problem that gas reservoir abandonment pressure is difficult to obtain;And based on the existing well pattern condition, establish the determination method of gas reservoir recovery ratio, achieve the purpose of quickly and accurately obtaining gas reservoir recovery ratio.

This invention belongs to the technical field of oil and gas field development and enhanced oil recovery, specifically relating to a bio-based ternary composite enhanced oil recovery system and its preparation method. The bio-based ternary composite enhanced oil recovery system of this invention, by weight, comprises: 800-2000 parts of biopolymer; 600-3000 parts of biosurfactant; 40-400 parts of bionanomaterials; and 200-800 parts of water. In the bio-based ternary composite enhanced oil recovery system provided by this invention, the composite enhanced oil recovery system of biopolymer, biosurfactant, and bionanomaterials fully leverages the synergistic effect of each component, demonstrating significant advantages in improving crude oil recovery and reducing environmental risks, and possessing good industrial application prospects and promotional value.

A core permeability testing device and method are disclosed, belonging to the technical field of oil and gas field development. The testing device includes a core holder for holding the core to be tested; a constant temperature chamber for providing the testing environment temperature, which is equal to the temperature of the tight gas reservoir; the core holder and the core to be tested are placed inside the constant temperature chamber; a confining pressure loading pump for applying confining pressure to the core holder, the magnitude of which is equal to the pressure of the overlying strata of the tight gas reservoir; and a high-pressure gas cylinder for pressurizing a standard container, which is connected to the core holder. The standard container forms upstream and downstream pressures applied to the core holder according to the formation pressure of the tight gas reservoir. The core permeability under temperature, pressure, and saturation conditions is obtained by measuring and calculating. The testing device of this invention has a simple structure, and only pressure needs to be measured during the testing process, without the need to measure flow rate, which can effectively improve the evaluation effect of tight gas reservoir permeability.

This invention relates to a star-rating management method and system for the deployment and implementation of gas field development wells, belonging to the field of gas field development technology. The invention first establishes an initial production estimation expression and dimensionless production curves for gas wells using dynamic production data from existing similar gas wells. Then, it uses these results to determine the production rate of newly deployed gas wells and, based on production and cost, determines the internal rate of return (IRR) for these wells. If the required IRR is not met, the deployment location and construction process of the new wells are re-optimized until the required IRR is achieved. Simultaneously, the star rating of the gas well's economic benefit is determined based on the IRR. Drilling is then carried out at the new well deployment location that meets the economic development requirements. After drilling, a more detailed fracturing design is conducted, and the IRR and star rating of the gas well are re-determined according to the new design. This invention effectively improves the targeting of single-well geological design and fracturing construction design, thereby improving development results and quality.

The invention discloses a multilayer heterogeneous oil reservoir water injection development balanced production well completion perforation optimization method, and relates to the technical field of oil and gas field development engineering. The method comprises the steps that S1, basic parameters of a multilayer oil reservoir are collected, and engineering constraints are determined; s2, performing numerical simulation on perforation near-well flow of the multi-layer oil reservoir based on basic parameters of the multi-layer oil reservoir and the engineering constraint, and establishing a skin coefficient inversion library; s3, a preset skin coefficient of each layer in the multi-layer oil reservoir is set, and water injection rate distribution of each layer of the multi-layer oil reservoir under the general water injection condition is calculated based on the preset skin coefficient; s4, on the basis of the water injection amount distribution, calculating the water drive leading edge advancing speed of the oil phase and the water phase; s5, on the basis of the water drive front edge advancing speed of each layer, the water drive front edge advancing speed variance of each layer in the multi-layer oil reservoir is determined; and S6, the steps S3-S5 are repeated, the preset skin coefficient set when the advancing speed variance of the water drive front edge of each layer is minimum is obtained, and the optimal perforation parameter combination at the moment is obtained.

The present application relates to oil and gas field development technology, disclose a kind of heavy oil reservoir hot water drive limit well spacing determination method. Including the following steps: S1, the starting pressure gradient corresponding to different temperature is obtained by percolation experiment test;S2, according to the starting pressure gradient corresponding to different temperature, determine the inflection point temperature of starting pressure gradient curve;S3, based on the inflection point temperature of pressure gradient curve, the percolation area between injection well and production well is divided;S4, based on the percolation area divided, the percolation resistance R of darcy percolation area between injection well and production well is calculated d ;S5, based on R d The pressure drop ΔP of darcy percolation area between injection well and production well is calculated d ;S6, based on ΔP d The length l of non-darcy percolation area between injection well and production well is calculated nd ;S7, based on l nd Determine the limit well spacing L of heavy oil reservoir hot water drive. The determination method can guide the formulation of heavy oil reservoir hot water drive development plan, improve development effect.

The embodiment of the invention relates to the technical field of oil and gas field development, and discloses a shale oil reservoir carbon dioxide huff and puff recovery ratio prediction method and equipment, and the method comprises the steps: determining a first influence weight for a fracturing fracture morphological parameter in geological parameters and fracturing construction parameters; determining a second influence weight of the geological parameter, the fracturing construction parameter, the fracturing fracture morphological parameter and the carbon dioxide huff and puff mining parameter on the shale oil well productivity; according to the fracturing fracture propagation key parameters, the microseism monitoring fracture morphological parameters, the numerical simulation fracturing fracture morphological parameters and a pre-generated type-2 fuzzy logic model, determining a fracturing fracture morphological propagation key parameter range under different geological parameter, rock mechanics and fracturing construction parameter grade conditions; and predicting the recovery ratio of the target shale work area according to the fracturing fracture form extension key parameter range and different artificial neural networks. According to the method, the shale oil reservoir CO2 huff and puff recovery efficiency can be efficiently, intelligently and accurately predicted.

The invention belongs to the technical field of oil and gas field development, and provides a carbonate reservoir permeability calculation method, system and device and a storage medium, and the method comprises the steps: dividing T2 spectrum distribution of different pore structure components based on a nuclear magnetic logging T2 spectrum distribution curve; establishing a corresponding relation between T2 spectrum distribution of different pore structure components and core analysis permeability data based on a graph clustering analysis method; and calculating the permeability of the whole well section of the target layer well logging based on the corresponding relation. According to the method, the permeability of the fractured-vuggy reservoir is accurately estimated and solved by establishing the contribution relation of the fractured-vuggy reservoir with different pore structures to the permeability.

This invention relates to the field of oil and gas field development technology, and discloses an intelligent testing method and system for the flow conductivity of fracturing proppant. The method includes: Step S1, constructing a simulated fracture unit; Step S2, filling the simulated fracture unit with a target fracturing proppant; Step S3, applying multi-level closure stress to the filled simulated fracture unit; Step S4, during the application of each level of closure stress, real-time acquisition of fluid dynamic data flowing through the simulated fracture unit; Step S5, calculating the real-time flow conductivity of the proppant based on the fluid dynamic data; Step S6, after applying each level of closure stress, calculating the breakage rate of the proppant in real-time through image analysis; Step S7, correcting the real-time flow conductivity calculated in Step S5 based on the breakage rate to obtain a corrected flow conductivity; Step S8, outputting the test results based on the corrected flow conductivity.

The invention provides a hydraulic fracturing crack propagation prediction method, system and equipment, and belongs to the technical field of oil and gas field development and yield increase. According to the method, aiming at the problem that the prediction precision is insufficient due to the fact that a traditional KGD and PKN model ignores fracturing fluid filtration failure, the whole fracturing process is decomposed into a plurality of continuous time periods through a coupling variable yield superposition principle and a Carter filtration model; the filter loss is calculated in each time period and corrected to obtain equivalent displacement, and then based on the equivalent displacement, a KGD or PKN model is adopted to calculate the half-crack length increment and the opening increment of the crack; and finally superposing the results of all time periods to obtain the total half-crack length and the total opening degree of the crack. According to the hydraulic fracturing crack propagation prediction method, system and equipment, the inhibition effect of filtration loss on crack propagation can be reflected more truly, the hydraulic fracturing crack propagation prediction method, system and equipment adapt to the variable displacement working condition in actual construction, and the prediction precision is remarkably improved.

The invention belongs to the technical field of oil and gas field development, and discloses a common heavy oil reservoir yield splitting method based on principal component analysis, which comprises the following steps: S1, collecting dynamic and static data in a research area; s2, according to liquid production profile data and production dynamic measure adjustment, analyzing the output condition of the small layer of the multi-layer commingling production well in the research area, and representing the output limit by using the permeability level difference and the viscosity level difference; s3, based on the output limit, first-stage splitting is conducted on the multi-layer combined producing well, and non-output layers are removed; s4, according to the production condition, static, dynamic and technological parameters related to the productivity serve as productivity influence factors, principal component analysis is conducted through SPSS software, and the main influence factors higher in productivity correlation are determined; and S5, based on the main influence factors, establishing a yield splitting model, and completing yield splitting of each output layer. According to the method, the established model is simple and effective, heavy oil reservoir development can be guided, and block reserve utilization and development benefits are remarkably improved.

The invention belongs to the technical field of oil-gas field development, and discloses a low-salinity formation water identification method, which comprises the following steps of: obtaining data corresponding to a test oil well through drilling data, and comparing step by step according to the obtained data to judge whether water is discharged from a formation; the invention further discloses a low-salinity formation water recognition device and equipment and a storage medium. The method is suitable for identifying the low-salinity formation water, whether water flows out of the formation or not is judged in real time by draining the test oil well, an important basis is provided for identifying the low-salinity formation water, and the defects of a formation water judgment method are overcome.

The invention discloses a preparation method and application of sand control fluid in an outer annular space of an oil-string casing, and belongs to the technical field of oil-gas field development. The preparation method comprises the steps that S1, the perforation aperture of the oil-string casing and the sand grain size and temperature of a sand production oil layer are obtained; s2, uniformly mixing a non-metallic mineral material, pulverized coal and natural organic compound particles, adding water, and roasting to prepare porous microspheres; s3, paraffin is added, and microspheres wrapping the paraffin are prepared; and S4, adding water and cement to prepare a primary sand control fluid, and adding a retarder or an accelerator to enable the primary sand control fluid to meet the set initial setting time to prepare the sand control fluid. After the prepared sand prevention fluid is solidified, the paraffin can be melted and discharged at the oil layer temperature, so that a sand prevention barrier is formed in an annular space outside an oil-string casing, and due to the fact that the microspheres are porous, a wellbore in the casing is communicated with a sand outlet oil layer, oil gas can enter an oil pipe through pores to be normally exploited and produced, and sand grains are isolated outside. The method is suitable for oil layer sand prevention in oil-gas field exploitation.

The present application relates to the technical field of oil and gas field development, in particular to a kind of calculation method of reserve control degree of multi-layer superimposed tight gas reservoir.A kind of calculation method of reserve control degree of multi-layer superimposed tight gas reservoir, the reserve control degree of gas reservoir=(the control reserves of all gas wells-intersection control reserves-waste control reserves) / geological reserves of gas reservoir.The present application establishes a kind of calculation method of reserve control degree of multi-layer superimposed tight gas reservoir, considers the difference of different production layer control radius and control reserves, and has important guiding significance to the effective development of multi-layer superimposed gas reservoir.