95 results about "Co2 flooding" patented technology

The present invention belongs to the technical field of oil and gas exploration and development. Disclosed are a nuclear-magnetic-resonance-based method and system for characterizing the degree of miscibility of CO2 flooding. The method comprises: on the basis of a slim tube method, testing the minimum miscible pressure of crude oil of a target oil reservoir and CO2 (S101); on the basis of the minimum miscible pressure, conducting CO2 oil displacement experiments using cylindrical cores, collecting, in real time, two-dimensional weighted nuclear magnetic resonance images and multi-component T2 spectra of a fluid in the cores varying over time and space, synchronously collecting an outlet-end fluid, and conducting a chromatographic test to obtain chromatographic test data (S102); and on the basis of the two-dimensional weighted nuclear magnetic resonance images, the multi-component T2 spectra and the chromatographic test data, performing dynamically-changing qualitative and quantitative characterization on the degree of miscibility, so as to obtain qualitative and quantitative characterization results of the degree of miscibility of CO2 and the crude oil (S103).

The invention discloses a peracetylated polysaccharide derivative mixing accelerator as well as a preparation method and application thereof, and relates to the technical field of polysaccharide derivatives. Alkyl polyglucoside and glycidyl ether are subjected to etherification reaction to obtain polysaccharide derivatives; and adding acetic anhydride and an organic weak base catalyst into the polysaccharide derivative, and carrying out esterification reaction to obtain the peracetylated polysaccharide derivative. The obtained peracetylated polysaccharide derivative can be used for reducing the minimum miscible pressure of CO2 in an offshore oilfield. The polysaccharide derivative provided by the invention is simple in synthesis process, and the molecular activity of the polysaccharide derivative can be regulated and controlled by changing the number of carbon dioxide-philic groups and the length of oleophylic unsaturated hydrocarbon chains, so that the polysaccharide derivative can be used in the CO2 oil displacement process of oilfield exploitation, and the minimum miscible pressure in the CO2 oil displacement process is effectively reduced.

According to the carbon dioxide oil displacement tank capable of automatically adjusting the pressure, during daily storage, the change speed and amplitude of the pressure in the tank are maximum, so that the stability of equipment can be influenced, an air bag is arranged in a third air cavity, and when the pressure in the third air cavity changes, the air bag is closed, so that the stability of the equipment is improved. The air bag can be matched with the third electric valve and the second electric valve to release or suck air so as to adjust pressure change, the speed and amplitude of the pressure change are slowed down to be within a controllable range, and therefore the stability of air stored in the device is improved, the interior of the tank body is divided into three storage units, and the storage effect is good. The third air cavity, the second air cavity and the first air cavity are sequentially arranged from inside to outside, when the first air cavity leaks, the third air cavity and the second air cavity are in a closed state and do not leak with the first air cavity at the same time, the capacity of the first air cavity is the minimum, the capacity of the third air cavity is the maximum, and if the first air cavity leaks, the loss can be reduced to the minimum. Therefore, the safety of the device can be improved.

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 field gas channeling plugging agents, and discloses a high-molecular pre-crosslinked gel particle plugging agent suitable for a carbon dioxide drive oil reservoir and a preparation method of the high-molecular pre-crosslinked gel particle plugging agent. The raw materials comprise an acrylamide monomer, sodium bentonite, an acrylic monomer, an acid-resistant functional monomer, a temperature-resistant and salt-resistant functional monomer, a first cross-linking agent, a second cross-linking agent, an initiator, an inorganic reinforcing agent, an antioxidant and water. The prepared acid-resistant gel particle is good in temperature resistance, salt resistance and acid resistance and long in effective period of action, the viscosity of a system is increased after the particle swells for a certain time, the plugging capacity is enhanced, and the acid-resistant gel particle can be used as an excellent CO2 drive reservoir gas channeling plugging agent and is used for plugging a heterogeneous formation with developed micro-cracks.

The application provides a kind of low permeability long fracture fracturing well group CO2 drive critical injection parameter evaluation method, comprising: carrying out CO2 injection well group reservoir characteristics fine description;Carrying out CO2 injection well group geomechanics parameter description;Establish low permeability long fracture fracturing well group CO2 drive reservoir matrix-fracture coupling numerical simulation model;Carrying out long fracture fracturing well group CO2 drive numerical simulation, evaluating reservoir pressure change;Carrying out long fracture fracturing well group CO2 drive disturbance stress field change evaluation;Carrying out long fracture fracturing well group CO2 drive fracture propagation determination, evaluating gas channeling and CO2 leakage risk, determining critical injection parameter limit.The low permeability long fracture fracturing well group CO2 drive critical injection parameter evaluation method combines the dynamic change evaluation CO2 drive critical injection parameter of low permeability long fracture fracturing well characteristics and reservoir physical parameter, and has important significance for improving CO2 drive development effect and realizing CO2 drive reservoir scientific management.

This application relates to a physical simulation device and method for determining the location of a CO2 flooding front, belonging to the field of physical simulation devices. The device includes a clamp, an imaging device sleeved on the outside of the clamp, an intermediate container filled with CO2 at the inlet end of the clamp, a back pressure assembly at the outlet end of the clamp, a metering assembly between the back pressure assembly and the clamp, and a confining pressure assembly on the clamp. This application has the effect of determining the location of a CO2 flooding front by analyzing changes in oil phase signals in core samples.

The invention discloses a low-permeability reservoir CO2 oil displacement storage synergistic interaction regulation and control device, which belongs to the technical field of low-permeability reservoir development and carbon storage, and comprises a CO2 source supply unit, an intelligent injection allocation regulation and control unit, a reservoir injection unit, an oil displacement monitoring unit and a storage synergistic unit which are communicated in sequence, all the units are networked through pipelines and are internally provided with data interaction modules to realize information closed-loop transmission, and the intelligent injection allocation regulation and control unit is a core control end; according to the low-permeability reservoir CO2 oil displacement and storage synergistic interaction regulation and control device, a supply, regulation and control, injection, monitoring and storage integrated closed-loop system is constructed, an intelligent injection allocation regulation and control unit serves as a core, the multi-element coupling relation of oil displacement efficiency, storage capacity and injection parameters is established through a synergistic interaction algorithm model, and according to the real-time dynamic state of an oil reservoir, the oil displacement efficiency, the storage capacity and the injection parameters can be adjusted and controlled according to the real-time dynamic state of the oil reservoir. And the operating parameters of each unit are dynamically adjusted, so that the optimal balance between the CO2 oil displacement efficiency and the storage capacity is realized, and the crude oil recovery rate of the low-permeability reservoir is improved.

The application relates to a multi-stage electric heating intelligent unblocking device and method for complex frozen blockage of a CO2 flooding waxy crude oil gathering pipeline, wherein the multi-stage electric heating intelligent unblocking device for complex frozen blockage of the CO2 flooding waxy crude oil gathering pipeline comprises a dredging system, an outer framework and an intelligent control system; the outer framework is a bionic flexible guide pipe which is composed of multiple body segment units connected through expansion joints; the dredging system integrates a first-stage global heating system, a second-stage local heating system and a dosing system; a flexible electric heating pipe is embedded in the bionic flexible guide pipe to form a uniform heating body; the bionic flexible guide pipe is provided with a temperature sensor; the second-stage local heating system is an intelligent composite drill bit which can autonomously heat; the intelligent composite drill bit comprises a motor system, a drill bit shell, an electric heating rod, a drill bit and a miniature night vision camera; the dosing system comprises an inhibitor storage tank and multiple nozzles. The application can quickly break the frozen blockage area and realize intelligent operation.

The application provides a CO2 oil displacement storage regulation optimization decision method and system, the method obtains a three-dimensional geological model, production dynamic data and monitoring data of a target working area; a component numerical simulation technology is used to fit a CO2 injection production dynamic history of the target working area, so that target operation parameters of a simulation operation model are adjusted and determined to obtain a matched production simulation operation model; a gas-oil ratio is determined according to the production dynamic data, and then a gas channeling index is calculated, and a target well group meeting the conditions of the gas channeling index is selected; a relationship curve distribution between a Peclet number, an oil increment and a component sweep efficiency is determined by simulating different injection speeds to determine an optimized target injection speed; and development parameters corresponding to different injection modes are simulated, and the target injection mode is determined in combination with the gas channeling index, the sweep efficiency and the miscibility degree. The scheme can overcome the defects of the prior art that the parameter optimization is not in place and the precision is insufficient, and can consider the particularity of the CO2 oil displacement mechanism to establish a regulation optimization strategy based on dimensionless parameters.

The invention discloses an emulsified particle channeling sealing agent for CO2 flooding as well as a preparation method and application thereof, and belongs to the technical field of CO2 flooding of oil reservoirs. The emulsified particle channeling sealing agent for CO2 flooding comprises the following components in percentage by weight: 20-30% of matrix asphalt, 1.6-2% of latex, 0.8-1.2% of a softening agent, 3-5% of an emulsifier, 0.1-0.5% of a dispersing agent, 0.4-1.3% of a pH regulator and the balance of deionized water. The emulsified particle channeling blocking agent for CO2 flooding can effectively block deep cracks or large pore channels of a reservoir, enlarge the sweep efficiency of CO2 in an oil reservoir and improve the CO2 flooding recovery efficiency, has excellent temperature resistance, acid resistance and salt resistance, and is harmless to a reservoir matrix.

The application belongs to the technical field of oil exploitation, and discloses a high-temperature and high-pressure full-automatic CO2 flooding and burying integrated experimental device and method, which comprises a core clamping system for clamping a core sample, and a pressure measuring system and a confining pressure system are communicated on the core clamping system; a fluid injection system is communicated with the core clamping system; a fluid property measuring system for measuring fluid properties is arranged on the fluid injection system; an output product separation system is communicated with the outlet of the core clamping system through a back pressure adjusting system, and the output product separation system is communicated with a fluid recovery system, a fluid analysis system and a fluid circulation system; and an output product measuring system is communicated with the core clamping system. The application realizes automatic control of the whole set of equipment, is suitable for evaluation of carbon dioxide enhanced oil recovery and in-situ storage, and can also be used for experimental research on related problems such as natural energy depletion development, secondary and tertiary oil recovery, expands the research field and enlarges the application range.

The invention discloses a wellhead throttling anti-freezing and anti-blocking device and method for a carbon dioxide flooding well, and relates to the technical field of carbon dioxide flooding wells. Wherein the oil nozzle comprises a first-stage oil nozzle and a second-stage oil nozzle arranged at the upper part in the heating box which are connected; the inlet end of the primary oil nozzle is connected with an outlet oil nozzle sleeve of the Christmas tree; the outlet end of the primary oil nozzle is connected with the inlet end of the secondary oil nozzle; the outlet end of the secondary oil nozzle is connected with the inlet end of the coil in the heating box; the outlet end of the coil penetrates out of the heating box and is connected with a gathering pipe communicated with the lower side of an oil outlet pipe of the Christmas tree. The method is a production management method which can adapt to the production change rule of the carbon dioxide flooding well on the premise that the conventional carbon dioxide flooding well mouth process and the electric power facility design are not rebuilt and expanded, and is economical.

The invention discloses a direct reinjection device for CO2 flooding produced gas, which is characterized in that an electric block valve, an electromagnetic heater, a gas-liquid separator, a molecular sieve dehydration pry, supercritical compression equipment and a reinjection unit are sequentially arranged along a flow node of the CO2 flooding produced gas, and an outlet of the reinjection unit is connected into a specified well; one bottom outlet of the gas-liquid separator is connected into the gathering and transporting system, the other bottom outlet of the gas-liquid separator is connected into the closed sewage tank, and the bottom outlets of the molecular sieve dehydration pry are connected into the closed sewage tank. The invention further discloses a direct reinjection method for CO2 flooding produced gas. The invention belongs to the technical field of carbon capture, burying and utilization, and solves the problems in the prior art that in the CO2 flooding extraction process, CO2 flooding extraction gas is high in CO2 content, the pressure in the open flow stage is high, and the extraction gas is difficult to enter a gas collection system. And the problems that in the prior art, CO2 drive produced gas is large in flow, high in CO2 content, large in fluctuation range and high in treatment cost are solved.

The present application relates to a kind of CO2 injection dynamic optimization method based on deep reinforcement learning and MRST reservoir numerical simulation coupling, belong to petroleum engineering intelligent optimization control technical field, to solve the serious dependence of artificial trial calculation in existing CO2 injection system optimization, dynamic decision-making ability is insufficient, physical simulation and intelligent decision-making are disjointed and safety constraint processing is insufficient and other problems.Through MRST, CO2 injection numerical simulation environment is established, state variables such as pressure field, CO2 saturation field, well control state, cumulative injection amount, storage amount index and constraint margin are constructed from simulation state, injection control action is output by deep reinforcement learning agent, MRST simulation is promoted after engineering constraint processing, reward is calculated and strategy is updated.The present application can be adjusted according to reservoir dynamic response Rolling injection strategy, applicable to CO2 geological storage and CO2 flooding and storage collaborative optimization scene.

The invention relates to the technical field of petroleum and natural gas engineering, in particular to an ester group-containing polypyridine quaternary ammonium salt corrosion and scale inhibitor and a preparation method thereof. The molecular formula of the ester-containing polypyridine quaternary ammonium salt corrosion and scale inhibitor is C45H44Br3N3O7, a polypyridine quaternary ammonium salt structure can form a multi-layer compact adsorption film on the metal surface through electrostatic adsorption and coordination, and introduced pyridine rings, ester groups and hydroxyl groups have a synergistic effect in the scale inhibition aspect. The corrosion inhibition rate of the ester-containing polypyridine quaternary ammonium salt corrosion and scale inhibitor can reach up to 98.87% in a saturated CO2 and 3.5% NaCl solution under the condition that the injection concentration is 200ppm; and the scale inhibition rate reaches up to 93.79% under the condition that the filling concentration is 60ppm. The ester group-containing polypyridine quaternary ammonium salt corrosion and scale inhibitor has corrosion and scale inhibition functions at the same time, and is especially suitable for an oil field in a CO2 drive oil extraction scene.

The invention discloses a CO2 flooding minimum miscible pressure prediction method, system and equipment for in-situ crude oil and a storage medium, and the method comprises the steps: S1, obtaining multiple pieces of CO2 flooding minimum miscible pressure data of in-situ crude oil with high intermediate component content, and carrying out the data preprocessing to remove extreme values; s2, establishing a multivariate linear regression model for predicting the minimum miscible pressure based on the preprocessed data, and removing the collinearity of the multivariate linear regression model through ridge regression to obtain a minimum miscible pressure prediction formula; and S3, predicting the minimum miscible pressure of the in-situ crude oil by adopting a minimum miscible pressure prediction formula. The method is suitable for CO2-driven formation crude oil of formation crude oil with high intermediate component content, and can accurately predict the minimum miscible pressure value.

This invention belongs to the field of CCUS-EOR technology and discloses an interpretable data-driven prediction and optimization method for CO2 enhanced oil recovery and storage. The method includes the following steps: using a CMG-GEM component simulator, numerical simulation is conducted through Monte Carlo sampling to obtain a multimodal data pipeline; a LightUFTrans hybrid model is built to achieve three-dimensional prediction of CO2-EOR and storage performance; LightUFTrans is embedded as a surrogate model into the LA-MONSGA-II optimization framework to obtain the Pareto optimal solution; and the model decision-making mechanism is analyzed from the dimensions of global features, temporal dependence, and spatial distribution by combining SHAP, attention mechanism, and spatiotemporal verification. This invention uses the above method to construct the LightUFTrans multimodal surrogate model, accurately depicting the dynamic evolution of underground spatiotemporal processes, significantly improving computational efficiency, and greatly reducing engineering design and decision-making costs; through multidimensional interpretability analysis, key engineering control parameters are identified, their temporal dynamic characteristics and spatial migration mechanisms are analyzed, overcoming the limitations of black-box models and improving engineering credibility.

The invention belongs to the technical field of oil and gas exploitation, and relates to a method, a system and equipment for determining formation starting pressure carbon absorption parameters and a medium. According to the method, the carbon injection pressure difference is obtained according to the flowing bottomhole pressure, the carbon absorption curve is established according to the daily carbon injection amount and the carbon injection pressure difference, the slope of the carbon injection curve visually represents the stratum carbon absorption index, and the stratum carbon absorption capacity can be rapidly and more accurately evaluated; the starting pressure of the carbon injection stratum is obtained according to the carbon absorption curve, and a basis is provided for model selection of a carbon injection compressor or a carbon injection pump; according to the carbon injection formation starting pressure and the formation static pressure, the carbon injection minimum bottom hole pressure is obtained; the carbon absorption index is obtained according to the flowing bottomhole pressure, the daily carbon injection amount and the starting pressure of the carbon injection stratum, the stratum carbon absorption index accurately represents the stratum carbon absorption capacity, and a powerful basis can be provided for ground engineering construction, carbon dioxide injection oil displacement recovery ratio improving scheme compilation, carbon dioxide injection geological design and the like.

The invention belongs to the technical field of carbon dioxide miscible-phase oil displacement, and particularly relates to a mixing reducer for carbon dioxide oil displacement as well as a preparation method and application thereof. The mixing reducer comprises a solvent and a solute, and the solute is formed by mixing a zwitterionic surfactant, a zwitterionic nonionic surfactant, an anionic sulfonate surfactant and a gemini nonionic surfactant. The mass ratio of the zwitterionic surfactant to the zwitterionic nonionic surfactant to the anionic sulfonate surfactant to the gemini nonionic surfactant is (3-9): (1-5): (5-12): (4-11). Four different types of surfactants are combined, due to the electrostatic attraction effect between electron groups of selected substances, a compact composite interfacial film of ionic crosslinking and nonionic filling is finally formed, the minimum miscible phase pressure of carbon dioxide in crude oil can be substantially reduced theoretically, and good environmental adaptability is achieved; and dissolution is not easy to occur at the reformation temperature.

This utility model discloses a compressed air device for carbon dioxide-driven oil recovery, belonging to the technical field of carbon dioxide-driven oil recovery equipment. It aims to solve the problems of insufficient self-adjustment performance in existing compressed air devices for carbon dioxide-driven oil recovery, limitations in removing dust and moisture from compressed air, and the need to improve overall working efficiency and stability. The key technical solution includes a first air compressor and a second air compressor. An air storage tank is installed on one side of both the first and second air compressors. Air guide pipes are installed at the outlet ends of both the first and second air compressors, and the other end of the air guide pipes is connected to the inlet end of the air storage tank. This achieves the effect of enabling self-adjustment operation while effectively removing dust and moisture from compressed air, thus improving the efficiency and stability of carbon dioxide-driven oil recovery.

The invention discloses a CO2 drive reservoir producing well shaft phase change point calculation method. The method comprises the following steps that S1, a bubble point temperature-pressure relation curve and a wax precipitation temperature-pressure relation curve of a target well are calculated; s2, calculating a temperature-well depth relation curve and a pressure-well depth relation curve of the target well under different working conditions; s3, calculating a bubble point temperature-well depth relation curve and a wax precipitation temperature-well depth relation curve under different working conditions; s4, calculating gas-liquid phase change point depths and wax precipitation phase change point depths under different working conditions; s5, obtaining a calculation formula and a calculation formula through multiple linear regression; s6, the actually-measured production conditions of the target well are substituted into the calculation formula, and the phase change point of the target well under the production conditions can be calculated. According to the method, rapid and accurate prediction of the phase change point of the shaft of the CO2 flooding producing well is realized.

The application belongs to the technical field of oil exploitation, and particularly relates to a dry ice heating and sublimation device for carbon dioxide oil displacement and a use method. The device comprises a cylinder, a sealing assembly, a stacking assembly and a heating assembly. The sealing assembly comprises a round plug, a lower lug, a round rod and a motor. The round plug is in sealing connection with the lower end surface of the cylinder. The output end of the motor drives the round rod to drive the round plug to move up and down. The stacking assembly is located in the cylinder and comprises a support frame and a plurality of round net plates. The heating assembly comprises a peristaltic pump, an electromagnetic heating plate, an external steel pipe connected with the peristaltic pump in sequence, and an internal steel pipe. The internal steel pipe is in a spiral shape and is located between the inner wall of the cylinder and the outer side of the support frame. The outer side of the external steel pipe is provided with the electromagnetic heating plate. The device can concentrate the dry ice and has a circulating flow heating assembly, so that the dry ice can be uniformly heated, sublimated quickly, the water flow speed is fast, and the situation that the water flow speed is slow and the pipe body is blocked by ice can be avoided.

The embodiment of the invention provides a carbon dioxide drive oil reservoir remaining oil characterization method, device and equipment and a medium, and belongs to the technical field of oil reservoir development. The method comprises the steps that according to a distribution field set, corresponding to each historical time step, of a target oil reservoir area, a remaining oil enrichment area set corresponding to each historical time step is determined; wherein the distribution field set comprises a residual oil residual potential distribution field and a carbon dioxide concentration distribution field; for each historical time step, determining respective related data of each remaining oil characterization index in a preset remaining oil characterization index set in the historical time step according to the remaining oil enrichment area set corresponding to the historical time step; and determining the remaining oil distribution index corresponding to each historical time step according to the related data of each remaining oil characterization index in each historical time step. The method is easy to operate, rapid and effective, the CCUS technology can be well guided to be achieved according to the result obtained through the method, and then the recovery efficiency is improved.

The present application relates to the technical field of heavy oil reservoir development, in particular to a screening method of viscosity reducer for carbon dioxide flooding, which comprises calculating the viscosity reduction rates of a plurality of viscosity reducers for heavy oil at different test temperatures, and then obtaining a plurality of viscosity reduction rate arrays of the viscosity reducers at different temperatures; based on the viscosity reduction rate arrays, based on the normalized values of the average viscosity reduction rate and oil displacement efficiency corresponding to each viscosity reducer, average normalization, standard deviation, coefficient of variation, weighted factor, the comprehensive evaluation index corresponding to each viscosity reducer is calculated, and the optimal viscosity reducer is screened based on the comprehensive evaluation index; the present application comprehensively evaluates the static viscosity reduction performance and dynamic oil displacement performance of the heavy oil viscosity reducer through the heavy oil viscosity reduction effect evaluation experiment and the physical simulation oil displacement experiment, thereby guiding the optimization of the viscosity reducer for carbon dioxide flooding, and realizing the maximum amplitude improvement of heavy oil reservoir recovery efficiency and the best economic benefit obtained by the carbon dioxide and viscosity reducer compound flooding.

The application provides a bottom water reservoir CO2 oil displacement and storage coordinated development method and system, which collects information of a target work area, and determines a component numerical simulation model matched with the target work area; determines a plurality of deployment positions of a horizontal injection well in a water layer in combination with water injection well conditions, oil layer thickness and oil-water interface positions of the reservoir, and uses the component numerical simulation model to simulate and calculate the deployment positions of the target injection well in order to optimize oil increment and storage capacity; further sets feasible injection parameters, and uses displacement effect and storage effect as optimization targets to simulate and calculate the injection mode of the target parameters; sets feasible injection and production speed combination schemes according to liquid production before gas injection, and simulates and calculates the injection speed and liquid production speed with the optimal oil increment and storage capacity. The scheme can overcome the problem of incomplete optimization effect in the prior art, effectively plays the energy and capacity of edge and bottom water, and realizes the increase of a large oil increment and the increase of CO2 storage capacity.

The application discloses a kind of low permeability reservoir CO2 drive oil storage simulation method and system, the simulation method includes: establishing low permeability reservoir CO2 drive oil storage model;The low permeability reservoir CO2 drive oil storage model is solved, and grid pressure distribution, component concentration distribution and crude oil viscosity distribution result are obtained.Improve the recovery efficiency of low permeability reservoir, while achieving the goal of increasing CO2 storage capacity.The model considers the adsorption of CO2 on the pore surface, the dissolution of crude oil, the dissolution of formation water and the mineralization of aquifer, etc.The model also considers stress sensitivity and threshold pressure gradient to reflect the characteristics of low permeability reservoir.

The application provides a kind of bifunctional polyelectrolyte nanoparticle material and its preparation method and its application in carbon dioxide flooding.The bifunctional polyelectrolyte nanoparticle material is core-shell structure, which is obtained by positive and negative electric adsorption after dissolving anionic CO2 response multi-copolymer and cationic CO2 body swelling gel microsphere material.The application also provides the preparation method of the above-mentioned bifunctional polyelectrolyte nanoparticle material and its application in carbon dioxide flooding.The bifunctional polyelectrolyte nanoparticle material provided by the application can be used for gas channeling large channel plugging, and after the "core-shell" separation of the nanoparticle material, the released inner core body swelling gel microsphere contacts CO2 to occur secondary expansion and efficiently plugs gas channeling channel.

The application relates to the technical field of oil exploitation and discloses a gas combustion system and a carbon dioxide oil displacement system, wherein the gas combustion system comprises a supply device, a fluidized bed boiler and a cyclone separator; the supply device is provided with a containing cavity for storing hydrocarbons, and the supply device is provided with a supply port in communication with the containing cavity; the fluidized bed boiler is provided with a hearth for burning the hydrocarbons, and the fluidized bed boiler is provided with a first boiler port, a second boiler port, a third boiler port and a fourth boiler port in communication with the hearth respectively, the first boiler port is in communication with the supply port, and the second boiler port is in communication with the atmosphere; and the cyclone separator is provided with a separation cavity for separating flue gas discharged from the hearth. The application can realize the combination of the carbon dioxide oil displacement technology and the gas combustion system in the technical field of oil exploitation, and provides a new idea for the preparation of carbon dioxide and oil displacement.