24 results about "Polymer flooding" patented technology

The invention discloses a polymer-flooding reservoir yield prediction method and system based on a double attention mechanism and a storage medium, relates to the field of oilfield development, and aims to solve the problems that a bidirectional dependency relationship and local features of long-time-series data are difficult to capture at the same time and feature weight distribution and time-series information focusing effects are insufficient in an existing method. According to the technical key points, the method comprises the following steps: S1, collecting field development data of the polymer flooding reservoir and screening optimization characteristics; s2, a CNN-BiLSTM-DAM fusion model is constructed, and the function implementation process of the model comprises the steps that local features of input data are extracted based on a convolutional layer, a dynamic weight is distributed to the local features of each time step through an attention mechanism layer, forward and backward dependency relationships of weighted time sequence feature data are captured through a bidirectional loop structure of a BiLSTM layer, and a dynamic weight is distributed to the local features of each time step; performing weight adjustment on the time sequence features output by the BiLSTM layer through the attention mechanism layer, and capturing global time dependence through the BiLSTM layer; and S3, the optimized features are input into the trained CNN-BiLSTM-DAM fusion model, and the yield of the polymer flooding reservoir is predicted.

The invention relates to the technical field of productivity evaluation, in particular to a thickened oil polymer flooding reservoir horizontal well productivity evaluation method and system.The method comprises the following steps that injection volume and daily fluid production data are collected to construct a sequence, rate transition and fluid volume inflection point judgment response starting are recognized, the fluid volume rising trend is analyzed to recognize a growth section, and the productivity of a horizontal well is evaluated. Dividing sub-intervals, evaluating fluctuation to determine an oil production stable section, and determining response association by combining concentration and a ratio to obtain a productivity section distribution interval. According to the method, the time sequence is constructed by collecting the daily injection volume, the rate transition is recognized, the production liquid increasing inflection point is extracted, the response starting moment is measured, the state of the horizontal well is recognized more accurately, based on the daily production liquid change comparison before and after starting, the daily oil production fluctuation in the lagging stage is evaluated, the stable oil production stage is screened, and the effective time of evaluation focusing is ensured. And a continuous descending starting point is delimited by comparing periodic oil production change, and the injection state is analyzed by combining the injection concentration and the liquid production ratio, so that productivity response staged identification is realized, and a basis is provided for adjustment.

The invention discloses a follow-up water drive potential tapping method based on flow field comprehensive analysis, and belongs to the technical field of potential tapping of remaining oil in a high-water-content stage in the middle and later periods of oilfield development. The method comprises the following steps: quantitatively identifying a dominant seepage channel based on streamline distribution, an oil saturation field and a water passing multiple of a target oil reservoir; dividing six remaining oil types and determining distribution characteristics of the remaining oil types; pressure system research and reasonable injection-production ratio regulation and control are combined, and differential potential tapping countermeasures for different remaining oil types are provided. According to the method, the development problems of high water content and low recovery degree in the subsequent water flooding stage of polymer flooding are effectively solved, and the oil reservoir recovery efficiency and development benefits can be remarkably improved.

The application discloses a method for judging the extension of the oil reservoir swept range of a microbial polymer system, and the steps are as follows: (1) taking the oil well samples in the oil reservoir before and after the microbial polymer flooding to perform the whole hydrocarbon gas chromatographic analysis of crude oil, and determining the small molecular weight light hydrocarbon marker component reflecting the change rule of the crude oil composition; (2) comparing the chromatographic peak area of the small molecular weight light hydrocarbon marker component with the chromatographic peak area of the high molecular weight carbon number, and obtaining the parameter for characterizing the effective action of the microbial polymer; (3) comparing and analyzing the crude oil samples in the oil well before and after the parameter for characterizing the effective action of the microbial polymer, and determining the swept degree of the oil reservoir by the microbial polymer. The application discloses the application of the above method in the microbial oil production for judging the swept volume of the microbial polymer in the oil reservoir.

The application discloses a method for determining the deblocking time of the near-well zone of a polymer injection well. The method comprises the following steps: S1, injecting a polymer solution into the polymer injection well; S2, measuring the injection pressure, and obtaining a relationship curve between the injection amount and the injection pressure according to the injection amount and the injection pressure of the polymer solution; and S3, determining the deblocking time according to the relationship curve: when the injection pressure is stable and then obviously decreases without a relieving trend, the deblocking time of the polymer injection well is determined. Based on the research on the solution percolation of a polymer flooding system in the near-well zone, the dynamic adsorption law of the polymer on the surface of rock minerals is determined, the dynamic adsorption has a process from quantity change to quality change, and the inflection point of the quality change is related to the formation of the near-well zone blockage, so the discrimination of the inflection point constitutes the selection of the deblocking measure time, and the application is formed.

The invention relates to the technical field of oil field polymer flooding, in particular to a method for inhibiting viscosity loss by preparing a polymer solution from oilfield purified water, which comprises the following steps of: 1, cleaning a polymer preparation container and equipment by using a compound degradation inhibitor, and keeping the cleaned polymer preparation container and equipment for later use; 2, purifying the oilfield produced water to obtain oilfield purified water; step 3, adding a required amount of compound degradation inhibitor into the cleaned polymer container and the oilfield purified water in the equipment, and stirring to obtain a polymer solution for polymer injection; and fourthly, after the polymer solution for polymer injection is injected into a reinjection wellhead, oil displacement is carried out. By adding the compound degradation inhibitor into the oilfield purified water, on one hand, the decomposition effect of bacterium breeding on polymers is inhibited, and various pollutants such as oil sludge prone to bacterium breeding in storage tanks and pipelines can be removed; on the other hand, the influence of system pollution on the viscosity of the polymer is eliminated, and the purpose of low viscosity loss in the polymer flooding process is achieved.

The invention discloses a polymer surfactant for oil displacement, and relates to the field of tertiary oil recovery. The problem that the oil displacement efficiency and the swept volume of an existing common polymer in a class III oil layer are not obviously improved in the oil layer is mainly solved. The molecular structural formula is as shown in formula (1), wherein R is H or CH3; r1 = H, CH3 or (CH2CH2O) yCH3, and y is in the range of 1 to 20; r2 = CXaCX3, X is halogen, a is 0-2, n, m and p are polymerization degrees, and the numerical ranges of n, m and p are as follows: n is 1-100000, m is 1-20000 and p is 1-30000; the synthesis method comprises the following step: synthesizing the surfactant for oil displacement from a raw material comprising a polymerizable surface active monomer by adopting a photo-initiation solution polymerization method or a reversed-phase suspension polymerization method. The polymer surfactant can be used as a tertiary oil recovery oil-displacing agent, has high viscosity in sewage, has certain surface activity, and can be used for further improving the recovery efficiency after tertiary oil recovery and polymer flooding of medium and low permeability oil layers.

The invention relates to the technical field of tertiary oil recovery, in particular to a method for quantitatively evaluating the effect of a multi-layer heterogeneous oil reservoir communication mode on polymer flooding development. The method comprises the steps that a target block is determined, chemical flooding static data are obtained, oil layer lateral communication modes and oil reservoir characteristics of the target block are determined, and geological models of different communication modes are established; setting a pre-polymer-flooding water flooding process and polymer flooding process parameters of the target block, and performing water flooding process simulation, polymer flooding process simulation and subsequent water flooding process simulation; respectively calculating a water flooding stage recovery ratio value, a polymer flooding stage recovery ratio improvement value and oil saturation decreasing amplitude in different connected mode water / polymer flooding processes of the target block; and comparing the water / polymer flooding development effects of the oil layers in different communication modes of the target block, determining the distribution rule of the remaining oil of the oil layers in different communication types of the target block, and providing technical guidance for potential tapping of the remaining oil in polymer flooding development of the target block. The method provided by the invention is high in repeatability, rapid in calculation and cost-saving.

A low-crosslinked flooding system for clastic reservoirs and its preparation method. The system comprises the following components: 0.05-0.1 wt% of a biopolysaccharide polymer, 0.1-0.45 wt% of an organic zirconium crosslinker, and a solvent. The biopolysaccharide polymer is diutan gum, and the solvent is high-mineralization simulated oilfield water. This polymer flooding system, primarily used for flooding in high-temperature oil-salt clastic reservoirs, is resistant to temperatures up to 110°C and salts up to 220,000 mg / l. The addition of an organic zirconium crosslinker to a biopolysaccharide system with excellent heat and salt resistance effectively improves the system's heat and salt resistance while reducing the biopolysaccharide concentration and system cost.

The invention provides a swellable particle with suspension property as well as a preparation method and application thereof, the swellable particle adopts cetyltrimethylammonium bromide, sodium dodecyl sulfate and sodium alcohol ether sulphate to participate in reaction, so that the volume of the swellable particle is increased, the density is reduced, and the suspension property is improved; the auxiliary agent overcomes the problems that the existing expanded particles are high in water absorption expansion speed and are too hard after being expanded; the thickening agent is added, so that the high pressure resistance after expansion is effectively guaranteed, and the water plugging agent can be used for oil well water plugging, high-water-content oil field deep fluid diversion and water flooding improvement. The problems that existing expansive particles are settled when encountering water, the water absorption expansion speed is high, and no suspension exists after expansion are solved; meanwhile, it is guaranteed that the high pressure resistance capacity is achieved after expansion, and the high-water-content oil field water plugging agent can be used for oil well water plugging and high-water-content oil field deep fluid diversion, the displacement effect of water flooding, polymer flooding and surfactant flooding is improved, and the oil reservoir recovery rate is increased.

The invention relates to a personalized injection parameter optimization design method based on emulsion polymer flooding. The method comprises the following steps: respectively carrying out core displacement experiments under different polymer dosages to obtain a first curve of each injection well; according to the deviation between the first curve and the second curve, the fitting deviation value of the injection well is determined; determining a heterogeneous value of the injection well according to the distance between each injection well and each adjacent injection well of the same type and the deviation between the recovery rates under each polymer dosage; performing weighted fusion on the first curve and the second curve of the injection well to obtain a target curve of the injection well, and determining the target polymer dosage of the injection well according to the target curve; according to the geological parameters and the pressure constraint parameters of each injection well, the injection speed of the injection well is determined, and the target polymer dosage is injected into the injection well based on the injection speed. According to the method, the polymer concentration and the polymer dosage can be matched for different injection wells, and the recovery ratio prediction precision is improved.

This invention relates to the field of petroleum extraction technology, and discloses a compound, a polymer with oil displacement function, its preparation method, and its application. The compound of this invention has the structure shown in formula (8); the polymer of this invention has good solubility at 20-95℃ and a salinity of 500-50000 mg / L, exhibits good viscosity-enhancing effect on the aqueous phase at high temperatures, can improve the mobility ratio, effectively expand the swept volume, and has good temperature resistance. Simultaneously, it can emulsify and disperse crude oil, reduce interfacial tension, and can be used for polymer flooding to improve oil recovery in conventional reservoirs, high-temperature and high-salinity reservoirs, and ordinary heavy oil reservoirs.

The invention relates to the technical field of intelligent control, and provides a method for recycling and optimizing a potential well pattern by excavating remaining oil after polymer flooding of a first-class oil reservoir, which comprises the following steps of: acquiring basic data of all unit grids in all grid units of a well pattern in a block after polymer flooding of the first-class oil reservoir; dead oil zone grids in the grid units are screened, and the remaining oil tapping potential of the dead oil zone grids is calculated; determining dead oil zone clusters formed by dead oil zone grids, calculating the comprehensive potential of the dead oil zone clusters, and screening high-potential dead oil zone clusters; the new well fitness of each dead oil area grid in the potential dead oil area cluster is calculated, new well positions determined by the potential dead oil area cluster are obtained, site selection is carried out on the new well positions again according to the relative distribution of all the new well positions, and optimization of reuse of the potential tapping well network is achieved. The invention aims to improve the well pattern reutilization optimization effect.

The invention relates to the technical field of intelligent temperature control, in particular to an intelligent temperature control method for electrical heating equipment of an injection station yard, which comprises the following steps: acquiring the environment temperature and PID (Proportion Integration Differentiation) control quantity in the polymer flooding injection station yard in real time; the superposition oscillation evaluation degree is calculated and used for evaluating complex changes of high-frequency superposition oscillation of the PID control quantity of the environment temperature in the frequency domain; the high-frequency change evaluation degree is calculated and used for evaluating the intensity degree of high-frequency component change of the environment temperature in the polymer flooding injection station within a short time; calculating a start-stop instability evaluation degree which is used for evaluating the possibility that the intelligent circuit breaker controller has a start-stop instability phenomenon; and the start-stop state of the intelligent circuit break controller is controlled through the start-stop instability evaluation degree, and intelligent temperature control over the electric heating equipment is achieved. The invention aims to realize accurate evaluation of the start-stop state of the intelligent circuit break controller of the electric heating equipment.

Some reservoirs have tight oil formations, such as the Changqing reservoir. The surfactant polymer flooding and low-tension gas flooding are two potential chemical flooding methods for use in tight oil formations. In these methods, an oil displacement agent, or surfactant, is added. Derivatives of nonionic surfactants with extended chains (by propylene oxide and ethylene oxide) from di-alkyl alcohols were developed and tested. A synergistic blend of surfactants was developed between the di-alkyl chain surfactants and anionic surfactants that lowers interfacial tension and improves surfactant solubility in high salinity water and oil.

The application discloses a kind of based on dual attention mechanism's polymer flooding reservoir production prediction method and system and storage medium, it is related to oilfield development field, to solve the problem that existing method is difficult to simultaneously capture the bidirectional dependent relationship and local feature of long time series data, and the effect of feature weight distribution and time series information focus is insufficient.The technical points of the present application include: S1, the field development data of polymer flooding reservoir is collected and optimized features are screened;S2, construct CNN-BiLSTM-DAM fusion model, the function realization process of model is as follows: based on convolution layer, the local feature of input data is extracted, the dynamic weight of each time step local feature is allocated by attention mechanism layer, the forward and backward dependent relationship of weighted time series feature data is captured by the bidirectional recurrent structure of BiLSTM layer, the weight adjustment of time series feature output by BiLSTM layer is carried out by attention mechanism layer, and then the global time dependence is captured by BiLSTM layer;S3, the optimized features are input into the trained CNN-BiLSTM-DAM fusion model, and the production of polymer flooding reservoir is predicted.

The application relates to the technical field of intelligent control, and proposes a remaining oil tapping well pattern reuse optimization method for a type of oil layer after polymer flooding, which comprises the following steps: acquiring basic data of all unit grids in all grid units of a well pattern in a block after polymer flooding of a type of oil layer; screening dead oil area grids in the grid units, calculating remaining oil tapping potential of the dead oil area grids; determining dead oil area clusters composed of the dead oil area grids, calculating comprehensive potential of the dead oil area clusters, and screening high-potential dead oil area clusters; calculating new well fitness of each dead oil area grid in the potential dead oil area clusters, acquiring new well positions determined by the potential dead oil area clusters, and re-siting the new well positions according to relative distribution of all the new well positions, so that the optimization of the tapping well pattern reuse is realized. The application aims to improve the optimization effect of the well pattern reuse.

The invention relates to the technical field of energy-saving transformation of equipment, in particular to a polymer flooding monitoring system for water-containing recovery periods of three types of oil layers. The system comprises an adjustment system switching judgment module used for calculating an injection electrical efficiency index by continuously monitoring oil production increment and power consumption of an injection pump during injection of a first adjustment system so as to judge whether to switch the adjustment system of an injection well at the current moment; the injection well energy-saving optimization module is used for dividing wells into two types according to an injection pressure space after a system switching condition is met: for an adjustable parameter well, a layered injection allocation scheme is formulated by calculating a layer section energy consumption weight and combining an oil layer thickness so as to realize energy conservation; and for the parameter adjustment limited well, fracturing resistance reduction is conducted on the production well communicated with the parameter adjustment limited well, and collaborative optimization is achieved through injection-production linkage. According to the embodiment, the polymer flooding decision is optimized by quantifying the energy consumption, and energy conservation and consumption reduction are achieved on the premise that the oil displacement effect is guaranteed.

Some reservoirs have tight oil formations, such as the Changqing reservoir. The surfactant polymer flooding and low-tension gas flooding are two potential chemical flooding methods for use in tight oil formations. In these methods, an oil displacement agent, or surfactant, is added. Derivatives of nonionic surfactants with extended chains (by propylene oxide and ethylene oxide) from di-alkyl alcohols were developed and tested. A synergistic blend of surfactants was developed between the di-alkyl chain surfactants and a commercially available anionic surfactants that lowers interfacial tension and improves surfactant solubility in high salinity water and oil.

The application provides a quick-dissolving oil-displacing polymer and a preparation method and application thereof. The method comprises the following steps: introducing inert gas A into an aqueous solution of an alkenyl monomer including N-[(4-sulfonamide)phenyl] acrylamide to remove oxygen, then introducing inert gas B micro-nano bubbles, and then initiating a polymerization reaction by at least one of the following methods: light initiation, thermal initiation, radiation initiation and redox initiation to obtain a colloid, and then treating the obtained colloid to obtain the quick-dissolving oil-displacing polymer. The introduction of sulfonic acid structural units and structural units with benzene ring structures significantly improves the hydrophilic ability of the side chain of the polymer and the heat resistance of the polymer, and simultaneously significantly improves the long-term viscosity retention rate. The porous structure of the polymer greatly reduces the dissolution time of the polymer. The free radical initiation effect of the micro-nano bubbles can play an auxiliary role in the free radical polymerization, can improve the polymerization efficiency, saves the polymerization cost, and can be used for polymer flooding in high-temperature and high-salt oil reservoirs.

The invention relates to a post-polymer-flooding oil reservoir chemical flooding injection scheme adjustment chart and adjustment method, specifically, based on the relationship between the fluidity ratio and the comprehensive water content and the relationship between the fluidity ratio and the flowing pressure, a comprehensive partition chart is established, adjustment countermeasures of all partitions continue to be made according to the dynamic characteristics of all effective partitions in the comprehensive partition chart, and the adjustment chart is obtained; then, according to the fluidity ratio of the oil phase to the displacement phase, the flowing pressure and the average water content of the well group in the specific area of the adjustment chart under the current oil saturation condition, a well group comprehensive adjustment scheme based on fluidity ratio control is formulated; according to conventional dynamic and static data of well group on-site development, timely monitoring of the fluidity ratio of a chemical flooding well group of an oil layer after polymer flooding can be achieved, an on-site injection-production scheme is adjusted in a targeted mode according to the current fluidity ratio, water content, flowing pressure and a comprehensive adjustment countermeasure chart of the well group, it is guaranteed that the fluidity ratio of a displacement phase to an oil phase in the whole chemical flooding process is smaller than 1, and the injection-production efficiency is improved. And the chemical flooding development effect of the oil layer after polymer flooding is further improved.

The present application belongs to the field of chemical profile control and flooding reservoir well test interpretation, and relates to a chemical profile control and flooding parameter design method and device based on a four-dimensional well test model. The chemical profile control and flooding parameter design method based on the four-dimensional well test model comprises the following steps: calculating a polymer flooding well test data after polymer profile control and flooding, and calculating a polymer mobility distribution field around a well and a circular distribution field of polymer viscosity around the well; combining a shape factor and using an equal-area conversion principle to draw an actual distribution field of polymer viscosity around the well; using a Petrophysical module in Petrel software to draw polymer viscosity actual distribution contour lines in different well groups together to generate a polymer viscosity distribution field map of the entire block; and determining a total polymer injection amount, a profile control slug amount and a channeling sealing slug amount of a single well group according to an area coefficient and a direction coefficient. The present application solves the problem that it is difficult to determine a polymer profile control and flooding reservoir plugging position, a profile control slug amount and a channeling sealing slug amount, and provides a scientific and reasonable theoretical basis for formulating a next profile control and flooding scheme.

The invention discloses a post-polymer-flooding chemical flooding injection scheme design method based on a fluidity ratio control theory, and solves the problems that the design viscosity of an oil reservoir permeability matching injection system before polymer flooding is relatively low, and the fluidity ratio of the injection system to in-situ crude oil cannot meet further oil flooding requirements. The method comprises the following steps: calculating a well group permeability range, and obtaining effective viscosity required by an oil layer; drawing relative permeability curves of displacement systems with different viscosities; according to morphological characteristics of the relative permeability curve, a relation formula of the water saturation and the relative permeability of the displacement phase and the oil phase is regressed, and a relation formula of the water saturation and the fluidity ratio of the displacement systems with different viscosities is obtained; calculating the fluidity ratio of different viscosity displacement systems under the current water saturation condition, regressing a displacement phase viscosity and fluidity ratio relation formula under the current water saturation condition, and calculating the target viscosity and the design viscosity of a well group oil layer; and determining the polymer design concentration of the single well displacement system. According to the method, chemical flooding injection parameters are reasonably designed, and the chemical flooding fluidity ratio control requirement of an oil layer after polymer flooding is met.

The invention discloses an oil field polymer flooding water treatment system, and belongs to the technical field of sewage treatment, the oil field polymer flooding water treatment system comprises a shell, the shell is internally provided with a polymer flooding water treatment system composed of a pretreatment tank, an oil removal device, a sedimentation tank, an ozone oxidation tank and an MBR membrane purification tank in sequence from right to left; according to the oil field polymer flooding water treatment system, a first rotating rod is arranged and can drive a mounting frame and a sieve plate membrane to rotate while rotating, polymer flooding water can be demulsified again through a modified polytetrafluoroethylene material of the sieve plate membrane when the sieve plate membrane rotates, the polymer flooding water can form vortexes when the sieve plate membrane rotates, and certain centrifugal force is generated; the centrifugal force generated by the vortex enables oil phase particles to float upwards to the center, when floating to the side face of the oil inlet, the oil phase particles can be conveyed into the oil storage tank through cooperation of parts, a water phase can be conveyed into the drainage groove along the upper edge opening of the oil removal barrel, and the oil phase collection efficiency can be improved conveniently.