86 results about "Carbon dioxide flooding" patented technology

The invention relates to the field of coal seam anti-reflection, and particularly discloses a coal seam carbon dioxide and static expanding agent synergistic anti-reflection system and method. Slurry prepared by mixing a static expanding agent and water is injected into the expansion fracturing drill hole, in the process that the static expanding agent is subjected to hydration reaction and generates expansion stress, carbon dioxide gas is injected into the expansion fracturing drill hole through the carbon dioxide gas injection pipe, carbon dioxide and the hydration product of the static expanding agent are subjected to carbonization reaction to generate larger expansion stress, and the expansion fracturing drill hole is formed. Expanding the coal body fractures to form expansion fractures; the carbon dioxide is driven by differential pressure to seep into a coal matrix along expansion fractures, and adsorbed gas is driven to be desorbed into a free state through a competitive adsorption effect; and under the combined action of extraction negative pressure and carbon dioxide displacement, the free-state gas moves from the fracture channel to the extraction drill hole, and extraction is conducted through the gas extraction system. Carbon dioxide and the static expanding agent cooperate to improve permeability of the coal body, the displacement effect of carbon dioxide on gas is promoted, and the gas extraction effect is improved.

The invention discloses a multi-site intelligent response type CO2 gas channeling prevention gel and a preparation method, and belongs to the field of chemical oil displacement, and the preparation method comprises the following steps: taking a carbon dioxide response type monomer, acrylamide and sodium acrylate as monomers, and adopting water-soluble free radical polymerization to prepare a CO2 response type copolymer; the CO2 response type copolymer, a cross-linking agent, a stabilizer, a retarder and formation water are prepared into a polymer cross-linking agent mixed solution, a cross-linking reaction is carried out under the conditions of formation temperature and mineralization degree, and the multi-site intelligent response type CO2 gas channeling prevention gel is obtained. The gel effectively solves the problems that a traditional anti-channeling agent is poor in injectivity in a low-permeability and ultra-low-permeability oil reservoir and cannot achieve deep channeling sealing, CO2 gas channeling fractured channels can be effectively blocked, the carbon dioxide oil displacement effect is remarkably improved, and key technical support is provided for large-scale application of carbon dioxide displacement.

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 invention discloses a device and method for evaluating the sealing performance of a shaft under the geological storage in-situ condition of carbon dioxide, and the device comprises a corrosion shaft test module, a carbon dioxide displacement module, a gas channeling simulation module, a shaft temperature and pressure control module and a stratum temperature and pressure control module. The shaft assembly is arranged in the testing shell in a penetrating mode, closed cavities are formed between the top end of the shaft assembly and the top end of the testing shell and between the bottom end of the shaft assembly and the bottom end of the testing shell, and a gas flow meter is installed at the top end of the testing shell. And a confining pressure bin and a heating bin are sequentially arranged in the test shell in the radial direction away from the shaft assembly. The device can simulate the lithology-temperature-pressure-carbonic acid environment in the geological storage process of carbon dioxide, and the sealing capacity of a shaft under the in-situ service condition is evaluated; therefore, the purposes of optimizing the formula of the cement paste, optimizing the material of the sleeve and reducing the risk of carbon dioxide leakage are achieved.

The invention belongs to the technical field of residual coal re-mining, and particularly relates to a gas and fire treatment method in the tunneling process of a lower-layer residual coal re-mining roadway, which comprises the following steps of: injecting gel foam into an upper-layer mining stopping line and an upper-layer open-off cut for leaking stoppage and cooling; advanced extraction is conducted on gas accumulated in a gas guide fissure zone of an overlying coal rock stratum of the upper-layer old goaf, meanwhile, carbon dioxide is injected into an air inlet and return roadway area of the upper-layer old goaf through a carbon dioxide injection drill hole in the ground, gas is displaced, and negative pressure air leakage of the upper-layer old goaf is prevented; and judging whether the residual coal in the upper-layer old goaf is spontaneously combusted or not, if the residual coal in the upper-layer old goaf is spontaneously combusted, increasing the carbon dioxide injection amount and the diffusion area, and performing advanced detection on the cavity in the process of tunneling the lower-layer roadway. According to the method, the risk probability of gas overrun, coal spontaneous combustion or gas explosion in the tunneling process of the lower-layer residual coal re-mining roadway is reduced.

The application provides a method for realizing pressure head migration by using a front carbon dioxide slug to assist water injection, comprising the following steps: step 1, establishing a model of water injection assisted by a front carbon dioxide slug; step 2, calculating the required water injection volume for water injection according to a production scheme and reservoir production data, and combining a pressure distribution model to optimize the volume of the required carbon dioxide slug; step 3, injecting the carbon dioxide slug according to the calculation result of step 2 to realize pressure head migration; and step 4, after the carbon dioxide slug is injected, water injection development is carried out in the way of water injection to form a development model of water and carbon dioxide slug oil displacement. The method for realizing pressure head migration by using a front carbon dioxide slug to assist water injection combines the advantages of water injection and carbon dioxide displacement, achieves good oil displacement effect at a low cost, and has a great application prospect in the development of low-permeability reservoirs, tight reservoirs and fault block reservoirs.

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 present application relates to coal mine gas extraction technology and equipment technical field, specifically relates to gas extraction drilling intelligent plugging-displacement production-increase redundancy protection integrated equipment and method, the equipment includes carbon dioxide displacement system, grouting system and gas extraction system, intelligent control system, the present application can carry out intelligent plugging to gas extraction drilling, greatly limit the airtightness of drilling is guaranteed, can displace the adsorbed gas in each layer, improve the extraction amount of gas, reduce the gas outburst risk, and increase the redundancy protection such as emergency closure device, increase the safety of extraction equipment. Greatly reduce the cost of manual intervention, improve the sealing effect of drilling plugging, compared with ordinary drilling plugging, improve the gas production, increase the safety of gas extraction operation.

The application discloses a kind of carbon dioxide drive injection well casing automatic pressure supplement device and automatic pressure supplement method, comprising: carbon dioxide storage tank;High-pressure injection pump, inlet is connected with the outlet of carbon dioxide storage tank, outlet is connected with the inlet of first tubing valve;Casing protection liquid storage tank;Reciprocating piston cylinder, one side of piston is A cavity, the other side of piston is B cavity;The end of reciprocating piston cylinder A cavity upper port is connected with the outlet of second tubing valve by first switch valve, the end of reciprocating piston cylinder A cavity lower port is connected with carbon dioxide absorption tank by second switch valve;The outlet of casing protection liquid storage tank is connected with the end of reciprocating piston cylinder B cavity upper port by third switch valve, the end of reciprocating piston cylinder B cavity lower port is connected with protection liquid injection pipeline by fourth switch valve, and the outlet of protection liquid injection pipeline is connected with the inlet of casing valve. Including gas injection, casing pressure supplement, piston reversing, circulating pressure increasing and the like steps. The application can accurately control casing differential pressure, reduce gas seal pipe column and packer leakage risk.

The invention relates to the technical field of oil and gas field development, in particular to a characterization method for quantifying contribution degrees of different mechanisms to improvement of gas reservoir recovery efficiency, which comprises the following steps: constructing an equivalent long rock core through a permeability harmonic average value, and restoring real reservoir seepage characteristics; three groups of experiments of natural exhaustion, static pressurization re-exhaustion and continuous gas injection displacement are adopted to realize physical decoupling of pressurization energy supplementation and a physical displacement mechanism; in combination with a homologous rock powder adsorption experiment, competitive adsorption contribution is accurately determined; a quantitative calculation model is established based on experimental data, and independent increments and comprehensive contribution degrees of the three mechanisms are obtained respectively. The method can solve the problem that the independent contribution degree of each single mechanism to extraction cannot be objectively and accurately quantified in the technology for improving the natural gas recovery efficiency through carbon dioxide displacement in the prior art.

The invention relates to the technical field of oilfield development, and discloses a method for improving carbon dioxide oil displacement effect, which comprises the following steps: (1) injecting a first composition into an oil reservoir, and then injecting carbon dioxide; wherein the first composition comprises xanthan gum, silicate and an optional first solvent; (2) injecting a second composition into the oil reservoir, and then injecting carbon dioxide; wherein the second composition comprises fatty alcohol polyoxyethylene ether sulfate, alkyl hydroxypropyl phosphate betaine, alkyl glycoside, coconut oil diethanolamide and an optional second solvent. By means of the method, the problem that the oil extraction rate is reduced due to gas channeling in an oil field can be effectively solved. According to the method, the fluidity of carbon dioxide gas in a reservoir high-permeability area or a crack can be effectively reduced, and the gas flooding sweep range is expanded, so that the carbon dioxide oil flooding effect is improved.

The invention belongs to the technical field of CO2 geological sequestration experiment evaluation in a CCUS-EOR project, and particularly relates to a carbon dioxide reservoir sequestration effect experiment comprehensive evaluation method. The method comprises the following steps: carrying out a carbon dioxide displacement saturated oil-water rock core experiment, simulating an actual oil reservoir CO2 injection and geological storage process, and calculating a storage evaluation index of CO2 in an experiment simulated oil reservoir on a rock core scale in combination with experimental test data; and quantitatively evaluating the carbon dioxide reservoir storage effect of the target reservoir under the corresponding working conditions by using the core scale CO2 storage index. The technical problem that a CO2 storage experiment method and a storage index quantitative evaluation method for oil reservoirs in the later stage of water flooding development are lacked at present is solved.

The application discloses a kind of carbon dioxide geological storage in situ condition wellbore sealing evaluation device and method, including corrosion wellbore test module, carbon dioxide displacement module, gas channeling simulation module, wellbore temperature and pressure control module and formation temperature and pressure control module, corrosion wellbore test module includes wellbore combination and test shell, wellbore combination is worn in test shell, and the top end between wellbore combination and the top end of test shell and the bottom end between wellbore combination and the bottom end of test shell form closed cavity, the top end of test shell is equipped with gas flowmeter, and test shell is sequentially provided with confining pressure bin and heating bin along the radial direction away from wellbore combination, the lithology-temperature-pressure-carbonic acid environment in the carbon dioxide geological storage process can be simulated by the application, the sealing capacity under the in situ service condition of evaluation wellbore is realized, to play the purpose of optimizing cement slurry formulation, optimizing casing material, reducing carbon dioxide leakage risk.

The invention relates to an oil reservoir injection-production optimization method, system and equipment fusing multiple proxy models. The method comprises the steps that a geologic model and a carbon dioxide flooding three-phase component model are established; determining constraint conditions, and obtaining an initial population; determining a target function; compiling a reference vector guide optimization algorithm code fusing multiple proxy models, and establishing a target database based on the carbon dioxide flooding three-phase component model, the initial population and the target function; adjusting parameters of the plurality of proxy models based on the plurality of established target databases; generating a filial generation population based on a genetic algorithm, and executing a reference vector guided optimization algorithm to update the target database; based on a given agent updating condition and the updated target database, preferably selecting an agent model of each stage; and obtaining a non-dominated scheme set of carbon dioxide flooding and a corresponding digital-analog result based on the optimized agent model of each stage. The method can be widely applied to the field of oil reservoir production optimization.

The invention discloses a dense oil reservoir carbon dioxide drive layered gas injection decision-making method. The method comprises the following specific steps that 1, a heterogeneous reservoir high-permeability gas suction proportion theoretical mathematical model based on the starting pressure gradient is constructed; 2, drawing a reservoir stratified gas injection permeability range boundary chart according to the theoretical mathematical model in the step 1; 3, the permeability and the permeability range of the low-permeability reservoir of the oil reservoir to be decided are obtained; 4, the permeability and the permeability range of the low-permeability reservoir in the step 3 form coordinate points, the coordinate points are substituted into the reservoir stratified gas injection permeability range boundary plate in the step 2, and when the coordinate points are located above a curve of the reservoir stratified gas injection permeability range boundary plate, stratified gas injection work is conducted on the reservoir to be decided; according to the method, by drawing the stratified gas injection boundary quantification chart of the reservoirs with different matrix permeability, the stratified gas injection permeability range boundary is defined, and the problem that the permeability range boundary of the carbon dioxide drive stratified gas injection reservoir is not clear is effectively solved.

This application relates to a foaming agent for carbon dioxide flooding in shale oil and its application, belonging to the field of carbon dioxide flooding technology. The foaming agent for carbon dioxide flooding in shale oil in this application comprises the following components by weight percentage: 4.0-6.0% betaine-type surfactant; 1.0-2.0% hexadecyltrimethylammonium bromide; 3-5% titanate coupling agent-modified silica particles; 0.1-0.5% ethylenediaminetetraacetic acid; 1-2% inorganic salt; and the balance being water. The foaming agent product provided in this application, with its betaine-type surfactant combined with titanate coupling agent-modified silica particles, adsorbs onto the gas-liquid interface, thereby improving the stability of the liquid film. The resulting CO2 foam exhibits improved high-temperature resistance. When applied to shale oil reservoirs with deep burial and formation temperatures around 100℃, it can significantly reduce gas cross-flow and improve sealing performance, ensuring its effectiveness under high-temperature conditions of around 100℃.

The invention discloses a basin-level carbon dioxide gas injection capacity planning method. The method is specifically implemented according to the following steps that 1, basic data parameters of different oil reservoirs of a target basin are collected; 2, according to the data parameters obtained in the step 1, a mathematical model of the oil reservoir carbon dioxide flooding annual gas injection amount is established, and the annual gas injection amount of different oil reservoirs is calculated; 3, the minimum miscible pressure of crude oil of different oil reservoirs in the target basin is obtained, and the types of carbon dioxide flooding of the oil reservoirs in the basin are divided; and 4, obtaining a source-sink distance, screening the annual gas injection amount obtained in the step 2 and the mixed phase type in the step 3, and planning the basin-level carbon dioxide gas injection and flooding capability. According to the method, the problems of long period and poor applicability of existing basin-level CCUS carbon dioxide gas injection capacity prediction are solved.

The application discloses a method and system for cross-scale characterization of space-time characteristics of a front during a carbon dioxide displacement process, and the method comprises the following steps: obtaining a one-dimensional scale carbon dioxide component front position by obtaining a fluid cross-section T2 signal along a path before and after carbon dioxide displacement; obtaining an oil-water distribution feature under original two-dimensional scale conditions and an oil-water distribution feature under different gas injection conditions to obtain a two-dimensional scale carbon dioxide component front distribution position; performing numerical simulation based on the one-dimensional scale carbon dioxide component front position and the two-dimensional scale carbon dioxide component front distribution position to obtain set parameters of one-dimensional and two-dimensional numerical simulation; and correcting parameters of three-dimensional reservoir scale numerical simulation based on the set parameters of one-dimensional and two-dimensional numerical simulation to obtain a three-dimensional reservoir model, judging a miscible pressure front, a component front and a phase front feature during the carbon dioxide displacement process, and completing the cross-scale characterization of the space-time characteristics of the front during the carbon dioxide displacement process.

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.

The invention relates to the technical field of well test interpretation, in particular to a carbon dioxide flooding phase state interactive seepage well test interpretation method which comprises the steps that a three-area composite seepage model of an injection well and a radial composite seepage model of a production well are solved; and explanation: drawing a corresponding pressure derivative curve according to each explanation method, respectively explaining by utilizing each well test explanation method, and taking the mutually matched explanation results as well test explanation results. According to the method, multiple well test interpretation methods are combined for mutual verification, the accuracy of interpretation results is improved, the multiplicity of the interpretation results is reduced, in addition, effective interpretation results can be obtained through the early well test interpretation method for the test wells which do not show radial flow and linear flow characteristic sections due to the fact that the well shut-in pressure recovery time is short, and the well test efficiency is improved. Compared with a traditional interpretation method, the early well test interpretation method has the advantages that the multiplicity of interpretation results is remarkably reduced, and a reliable basis is provided for carbon dioxide flooding miscible phase development.

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 invention discloses a low-permeability reservoir carbon dioxide flooding numerical simulation method based on Maxwell-Stefan cross diffusion, and belongs to the technical field of reservoir numerical simulation and recovery efficiency improvement. Comprising the following steps: establishing a mass conservation equation of each component based on an oil reservoir thermodynamic field, a rock physical property field, an effective diffusion coefficient matrix and reaction kinetic parameters; a diffusion flux item is expressed by a generalized Fick law based on a Maxwell-Stefan theory so as to describe a multi-component cross diffusion effect; a reaction source convergence item is determined by a COand crude oil reversible miscible phase kinetic model so as to describe a miscible phase and split phase dynamic process; sequentially executing a diffusion transmission step and a chemical reaction step for solving by adopting an operator splitting method to obtain an updated concentration field, and synchronously updating the thermodynamic field, the rock physical property field, the reaction kinetic parameters and the effective diffusion coefficient matrix; repeatedly iterating until each field and parameter change meet a convergence condition, and completing simulation of each chemical component concentration field; according to the method, the physical simplification defect in low-permeability simulation is overcome, and high-precision prediction of the displacement process is achieved.

The invention discloses a cross-scale characterization method and system for front edge migration spatial-temporal characteristics in the carbon dioxide displacement process. The method comprises the steps that fluid on-way section nuclear magnetic T2 signals before and after carbon dioxide displacement are obtained, and the front edge position of a carbon dioxide component under the one-dimensional scale is obtained; obtaining oil-water distribution characteristics under two-dimensional original conditions and oil-water distribution characteristics under different gas injection quantity conditions, and obtaining a front edge distribution position of a carbon dioxide component under the two-dimensional scale; performing numerical simulation based on the front edge position of the carbon dioxide component under the one-dimensional scale and the front edge distribution position of the carbon dioxide component under the two-dimensional scale to obtain set parameters of one-dimensional and two-dimensional numerical simulation; and correcting parameters of three-dimensional oil reservoir scale numerical simulation based on parameters set by one-dimensional and two-dimensional numerical simulation to obtain a three-dimensional oil reservoir model, judging miscible-phase pressure front edge, component front edge and phase front edge characteristics in the carbon dioxide displacement process, and completing cross-scale characterization of front edge migration spatial-temporal characteristics in the carbon dioxide displacement process.

The application discloses a temperature-resistant and salt-resistant foam stabilizer for carbon dioxide oil displacement and a preparation method thereof, and belongs to the technical field of chemical agents for carbon dioxide oil displacement. The temperature-resistant and salt-resistant foam stabilizer for carbon dioxide oil displacement comprises, in mass fraction, 0.8-1.2% of sulfobetaine-fluorocarbon copolymer, 0.12-0.2% of fatty alcohol polyoxyethylene ether sulfonate, 0.2-0.3% of modified nano ZnO, 0.08-0.12% of quaternized hydroxypropyl starch, 0.05-0.10% of aminotri (methylene) phosphonic acid, 0.05-0.08% of carboxymethyl modified xanthan gum and the balance of water, wherein the modified nano ZnO is prepared by coating nano ZnO with polydopamine. By limiting the component composition of the foam stabilizer, the problems of the existing foam stabilizer, such as insufficient salt resistance, poor anti-agglomeration, insufficient high-temperature resistance and poor degradation resistance, can be effectively solved. The components have strong synergism, the preparation process is simple and industrialized, the agent has good compatibility, the reservoir has low damage, the foam stability of CO2 and the oil recovery rate can be remarkably improved, and the foam stabilizer has high practicability.

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.

The present application relates to the technical field of oil and gas field development, in particular to a kind of determination method for injection-production ratio in carbon dioxide displacement effective period, first consider the carbon dioxide channeling characteristics, accurately define the more accurate carbon dioxide displacement effective period starting moment by combining dynamic monitoring with prediction algorithm and based on the prediction deviation of carbon dioxide volume fraction, provide reliable time base for subsequent injection-production ratio calculation;Then based on Peng-Robinson state equation and multiphase fluid volume conversion method, systematically convert the ground injection and discharge into underground volume, so that the accuracy of the obtained carbon dioxide underground injection volume and total amount of backflow fluid underground is higher;Further, more accurate injection-production ratio is calculated by combining the relative size of carbon dioxide underground injection volume and total amount of backflow fluid underground.

The invention discloses a method for displacing natural gas through carbon dioxide, and the method comprises the steps that the gas injection amount of carbon dioxide to be injected is determined; controlling a first valve opening degree of a pressure regulating valve and a second valve opening degree of a gas flow control valve on the basis of the injected gas amount so as to inject the carbon dioxide into a natural gas storage area through a gas injection unit; an exhaust gas analysis unit for analyzing the exhaust gas after the carbon dioxide has been injected into the natural gas storage area, and extracting the natural gas from the exhaust gas; and the concentration of the natural gas is determined, and under the condition that the concentration of the natural gas does not meet the natural gas recovery condition, the first valve opening degree of the pressure regulating valve is controlled again based on the injected gas amount, and the second valve opening degree of the gas flow control valve is controlled again based on the injected gas amount. The problem that the efficiency of displacing natural gas by carbon dioxide is low in the prior art is solved.