15 results about "Carbon dioxide flooding" patented technology

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 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.

This invention relates to a method for predicting the miscibility of carbon dioxide flooding, belonging to the field of oilfield development technology. The method of this invention, from a microscopic perspective of component changes, directly and quantitatively characterizes the reservoir miscibility after CO2 flooding. After CO2 injection into the reservoir, the miscibility coefficient is used to characterize the changes of various components in the crude oil within the affected area, thereby calculating the CO2 flooding miscibility within that area. This allows for the evaluation of the CO2 flooding effect in the target block. This method improves the prediction accuracy of carbon dioxide flooding miscibility, provides a basis and technical support for evaluating the effect of injected gas blocks, and can also guide the preparation of CO2 flooding reservoir engineering plans.

The invention provides an injection-production control method, device and equipment and a storage medium, and the method comprises the steps that a control parameter set meeting the crude oil production requirement is determined from a plurality of injection pressure given values and a plurality of injection rate given values based on an injection-production prediction model; taking a preset injection pressure given value and a preset injection rate given value in the control parameter group as an injection pressure control value and an injection rate control value of carbon dioxide to control the carbon dioxide to be injected into the injection well, and monitoring an actual production value of crude oil produced from the production well; and in the carbon dioxide oil displacement production process, whether abnormal well conditions exist in the production well or not is recognized according to the actual production value and the predicted production value, and the predicted production value is obtained based on the injection-production prediction model. By optimizing the injection pressure and the injection rate in carbon dioxide oil displacement and monitoring the well condition of the production well in real time, the crude oil recovery rate can be increased.

The application relates to the technical field of low-carbon oil exploitation, in particular to a method for constructing a CO2 drive flow field of a mud crack type shale oil reservoir, which comprises the following steps: obtaining CO2 injection speed, flow pressure of a production well and oil displacement rate in a CO2 oil displacement process; analyzing flow pressure change of the production well to construct a flow pressure fluctuation value; obtaining a flow pressure fluctuation influence degree according to the difference between the flow pressure fluctuation value and the change of the injection speed; constructing optimization control strength of each optimization stage in combination with the change degree of the oil displacement rate; obtaining an injection speed optimization value through the difference between the injection speed of each sampling time in each optimization stage and a preset injection speed expected value; and injecting the CO2 gas source into the injection well to form the CO2 drive flow field. The application can improve the shale oil recovery rate.

The present application relates to the technical field of oil produced water treatment, and particularly relates to a carbon dioxide flooding produced water pretreatment process, the pretreatment process comprising the following steps: (1) air floatation treatment: carbon dioxide flooding produced water enters an air floatation unit, and carbon dioxide and oil are preliminarily removed to obtain air floatation unit effluent; (2) electrochemical flocculation: the air floatation unit effluent enters an electrochemical unit, the pH is adjusted to be acidic, a flocculating agent is added, carbon dioxide is recovered, and suspended solids are removed to obtain electrochemical unit effluent; (3) filtration: the electrochemical unit effluent enters a filtration unit, and suspended solids are further removed to obtain filtration unit effluent. The present application has the advantages of low operation cost, low unit investment cost, convenient operation and management, and high removal efficiency.

The application relates to the technical field of oil development, and particularly discloses a carbon dioxide injection-production parameter multi-target optimization method based on Spark distribution, which aims at the problems of large calculation amount of injection-production parameter optimization, target function conflict and the like in the carbon dioxide flooding and storage process, and builds a multi-target optimization model containing cumulative oil production, CO2 storage amount and net present value. By using an Apache Spark distributed computing framework, population individuals are mapped into elastic distributed datasets, and a high-time-consuming oil reservoir numerical simulation task is distributed to cluster computing nodes for execution through a parallel scheduling mechanism; a multi-target aggregation strategy is provided, global non-dominated sorting and congestion calculation are performed on fitness results returned by each node at the Driver end, so that a Pareto optimal solution set is generated. The application can effectively shorten the optimization period, provides diversified injection-production parameter configuration schemes for decision makers on the premise of giving consideration to economic benefits and environmental benefits.

The application provides a carbon dioxide drive asphaltene deposition numerical simulation method, device and storage medium. The method comprises the following steps: obtaining basic physical property data of a target asphalt sample, and dividing the target asphalt sample into a first pseudo-component that is soluble in low molecular saturated hydrocarbon and a second pseudo-component that is insoluble in low molecular saturated hydrocarbon; determining the physical property parameters of the first pseudo-component through an experiment, and inversely calculating the physical property parameters of the second pseudo-component by using a mixing law in combination with the basic physical properties of the sample; obtaining asphaltene deposition experimental data of the sample under different temperatures, pressures and CO2 concentrations, calculating the molar fraction of the second pseudo-component in a fluid phase after deposition, and determining a solid-liquid equilibrium K value as the ratio of the molar fraction of the second pseudo-component to the molar fraction of 1 in a solid phase; introducing the K value into a reservoir numerical simulator, establishing a multi-phase and multi-component model based on mass conservation and multi-phase percolation equations, coupling a porosity and permeability dynamic change model, and predicting asphaltene deposition behavior in a CO2 drive process and the influence of the asphaltene deposition behavior on reservoir physical properties.

The application discloses a kind of carbon dioxide oil displacement simulation methods based on digital core model, it is related to oil and gas exploration and development field, solve the problem that existing technology adopts real core model has long test cycle, observation measurement parameter exists deviation insufficient etc..The application creates digital core model using real core pore structure characteristics, combines machine learning and artificial intelligence algorithm, fully couples different physical processes, according to different crude oil properties (density, dynamic viscosity), different CO2 injection rate and other parameters, to simulate the dynamic distribution characteristics of remaining oil in the process of CO2 displacement in underground reservoir with single variable.The application method is suitable for low-permeability-low-permeability reservoirs, medium-high permeability sandstone heavy oil reservoirs (CO2 assisted huff and puff) and fractured oil and gas reservoirs for CO2 displacement, and has important significance for evaluating the development effect of CO2 injection in oilfield.The application method avoids the tedious process of repeated oil washing of real core, and improves work efficiency.

This invention discloses a cylinder-driven, sealed, low-resistance, dense-phase carbon dioxide booster pump, belonging to the field of plunger pump technology. It includes: a housing with an inlet chamber and an outlet chamber, the inlet chamber being connected to an inlet port on the housing; a movable cylinder housed within the housing; when the movable cylinder moves to one end, a negative pressure is created at the inlet port, allowing liquid carbon dioxide from the inlet chamber to enter the outlet chamber; when the movable cylinder reaches the other end, the outlet chamber is sealed; a plunger extends into the movable cylinder; when the plunger moves within the housing, a volume change is created, thereby drawing in and compressing liquid carbon dioxide; a spring is sleeved around the plunger and located between the movable cylinder and the housing, applying resistance or thrust to the movable cylinder. This invention has a wide range of applications, particularly suitable for the operating conditions of carbon dioxide flooding in oil fields, effectively reducing kinetic energy loss by more than 5%. It adopts a reciprocating working principle, possessing good controllability and low investment cost, thus ensuring the stability of the carbon dioxide flooding injection process.

The utility model discloses an injection device for carbon dioxide oil displacement, including chassis, pressure tank, carbon dioxide inlet pipe and two groups of compensation column cavity shell, the pressure tank fixed mounting is to the chassis, two groups the one end of compensation column cavity shell all is connected to the pressure tank through one -way compensation exhaust pipe, the pressure tank is connected with injection pump head through pipeline, the outside installation of pressure tank has controller, the end of carbon dioxide inlet pipe is equipped with the four -way pipe head, one pipe head of four -way pipe head is connected to the pressure tank through pipe one -way inlet pipe, two pipe heads of four -way pipe head are connected to two compensation column cavity shell respectively through one -way compensation inlet pipe, and the sliding plug in the compensation column cavity of compensation column cavity shell is equipped with the compensation plug. Advantageous effect lies in the stability of carbon dioxide whole injection oil displacement process is realized through the compensation power structure cooperation pressure tank, reduces the unstable flow and the injection instability situation caused by the storage tank storage capacity change.

The application provides a carbon dioxide oil displacement sealing well spacing decision method and system, which comprises the following steps: firstly, carrying out crude oil-CO2 phase state experiment of a target reservoir to determine the viscosity variation characteristics of crude oil before and after CO2 injection; calculating the starting pressure gradient according to the viscosity of crude oil before gas injection and the minimum viscosity of crude oil after gas injection reflected by the experiment; then calculating the minimum driving pressure gradient under different injection-production well spacings to determine the injection-production well spacing before and after gas injection; calculating the economic limit well spacing and the economic best well spacing of the target reservoir by using the curve intersection method; determining the relationship curves between the well spacing and the CO2 displacement miscible degree and the CO2 displacement component sweep efficiency respectively; and selecting the target well spacing by comprehensively considering the distribution characteristics of the injection-production well spacing before and after gas injection, the economic limit well spacing and the economic best well spacing. The scheme can overcome the problems of the prior art, such as incomplete consideration of factors and insufficient accuracy of well spacing range selection, and forms an efficient and reliable well spacing calculation method by comprehensively considering the CO2 oil displacement mechanism, the reservoir characteristics and the economic benefits.

The application discloses a kind of based on CO2-oil interaction's relative permeability determination method and system, and the application relates to oil and gas development technical field, comprising the following steps: preparation of different carbon dioxide molar fraction oil sample, and by near infrared spectrum establishes the calibration curve of absorption peak area and molar fraction, prepare the core for experimental simulation, inject water to saturation after injecting formation crude oil displacement water to determine irreducible water saturation, carry out carbon dioxide displacement experiment under set pressure, measure the absorption spectrum of produced oil, to identify carbon dioxide breakthrough moment, the displacement process is divided into two stages, and calculate dynamic interaction parameter, introduce these parameters to modify JBN algorithm, determine oil phase and gas phase relative permeability, and combine gas saturation and carbon dioxide molar fraction, draw relative permeability curve, complete permeability determination, the method has higher practicality and accuracy.