72 results about "Acid fracturing" patented technology

The invention provides a natural fracture acid fracturing process parameter optimization method and device, equipment and a medium, and the optimization method comprises the steps: obtaining geological and engineering data of a target block, carrying out the fitting of the geological and engineering data to obtain a natural fracture fitting model, determining the natural fracture fitting parameters according to the natural fracture fitting model, and carrying out the acid fracturing process parameter optimization of the target block. Further establishing a pressure drop characteristic parameter model and a natural fracture characteristic parameter model by using actually measured pressure data, and further establishing a productivity prediction model; and according to the productivity prediction model and the natural fracture fitting model, optimizing the acid fracturing process parameters of the natural fractures. According to the method, the condition of natural fractures encountered by underground hydraulic fractures is innovatively and dynamically judged according to the wellhead pressure change rule in the multi-stage alternate acid fracturing process, parameters can be dynamically adjusted on this basis to achieve dynamic optimization of a pump injection program, and a basis is provided for whether the natural fractures are transformed or not in real time in the construction process; and a new thought and a new method are provided for acid fracturing parameter design and optimization.

The application provides a compact dolomite reservoir composite acid fracturing process parameter evaluation system and method, which comprises a simulated fracture device, an acid injection device and a circulating water injection device. The acid injection device comprises an acid storage container, an acid injection pipeline and an acid discharge pipeline. The acid injection pipeline is connected to the acid storage container and the acid injection liquid inlet hole of the simulated fracture device at both ends. The acid discharge pipeline is connected to the acid injection liquid outlet hole of the simulated fracture device. The circulating water injection device comprises a water storage container, a water inlet pipeline and a circulating water discharge pipeline. The water inlet pipeline is connected to the water storage container and the water injection liquid inlet hole of the simulated fracture device at both ends. The circulating water discharge pipeline is connected to the water injection liquid outlet hole of the simulated fracture device and the water storage container at both ends. The application adopts reverse thinking to evaluate the composite acid fracturing process parameters such as the preflush / acid viscosity ratio, the pump injection displacement and the alternating series by taking the fractal dimension, the acid volume, the flow conductivity and the acid fluid loss as the targets, and is more specific and systematic.

The invention discloses a hydrogen sulfide scavenger for acid fracturing and a preparation method thereof, and relates to the technical field of hydrogen sulfide scavengers, the hydrogen sulfide scavenger comprises the following raw materials by weight: 30-45 parts of an aldehyde compound, 30-45 parts of an alcohol amine compound, 10-18 parts of a diamine bridging agent, 2-6 parts of a solubilizing compounding agent, 20-30 parts of a solvent and 1-3 parts of a catalyst; the aldehyde compound is divided into a component A and a component B, the mass ratio of the component A to the component B is 2: 1-3: 1, the component A is paraformaldehyde, and the component B is at least one of glyoxal or glutaraldehyde. By optimizing a molecular skeleton and introducing a hydrophilic group, the sulfur removal capacity and chemical stability in a strong acid environment are improved, compatibility with acid liquor is good, generation of acid sludge and insoluble precipitates is effectively inhibited, secondary damage to a stratum is avoided, and the high efficiency and mass transfer performance of a product are guaranteed through the preparation process.

The application provides a method and system for calculating the conductivity of a sand-acid fracturing reservoir simulation system, which comprises the following steps: constructing a simulation parameter combination set around sand-acid fracturing operation parameters for reservoir types with sand-acid fracturing requirements; analyzing fracture acid erosion data of different reservoirs by using a preset fracture acid erosion calculation model, and analyzing the embedding depth and deformation data of the proppant in combination with the injection rate parameters and the proppant data; further analyzing the sand concentration of sand-acid fracturing, and setting a rough body simulation distribution coefficient in combination with the injection rate, so as to form a reservoir fracture model that presents a real fracturing state; analyzing the permeability state of the reservoir fracture model after fracturing based on the rough body simulation distribution coefficient and the reservoir closure pressure; and further calculating the corresponding conductivity in combination with the fracture width calculated according to the fracture acid erosion data, the embedding depth and deformation data of the proppant. The method solves the problem that the sand-acid fracturing conductivity cannot be quantitatively analyzed, and provides support for field acid fracturing design and productivity prediction.

The invention discloses a high-temperature and high-pressure corrosion on-line porosity and permeability testing method. According to the method, an integrated process of triple dynamic correction-multistage self-cleaning filtration-AI self-adaptive collaborative testing is constructed, and high-precision online continuous testing of the porosity and the permeability in the corrosion process is achieved under the conditions of the confining pressure of 0-120 MPa, the pore pressure of 0.1-50 MPa, the temperature range of 25-220 DEG C and the multi-medium supercritical corrosion working condition; the problems that in an existing high-temperature and high-pressure corrosion test, pressure-temperature-concentration coupling correction is not comprehensive, corrosion products are accumulated for a long time and are prone to blockage, the fluid stability under the supercritical working condition is poor, and the test frequency adaptability is insufficient are solved. The method can accurately capture the instantaneous evolution law of rock physical properties in a complex corrosion environment, is suitable for extreme scenes such as deep CO2-EOR sealing, ultra-deep oil and gas reservoir acid fracturing transformation and high-temperature geothermal reservoir long-term operation, and provides data support with higher fidelity for engineering scheme optimization.

This invention discloses a method, equipment, and medium for calculating construction parameters of sand-added acid fracturing stimulation, relating to the field of carbonate reservoir stimulation. Based on the single-well production requirements of the oilfield development plan, it determines the target artificial fracture length and conductivity; determines the fracturing fluid volume required to achieve the target artificial fracture length; determines the proppant volume required for sand-added acid fracturing stimulation according to the principle that permeability is supported by the filler; establishes a flow reaction model and temperature field model within the acid fracture to determine the concentration field, velocity field, and temperature field within the fracture during acid injection; and determines the actual permeability formed by acid dissolution and the acid volume required for sand-added acid fracturing stimulation based on the acid concentration and flow rate at different times in the fracture. This invention accurately determines the construction parameters of the pre-fracturing acid, proppant, and acid for sand-added acid fracturing stimulation, providing a basis for the design and optimization of acid fracturing processes in carbonate reservoirs.

The invention provides a salt-sensitive self-thickening weighted acid fracturing system as well as a preparation method and application thereof, and belongs to the technical field of acid fracturing of oil fields. The salt-sensitive self-thickening weighted acid fracturing system comprises the following components in parts by weight: 27-40.5 parts of a hydrochloric acid aqueous solution, 10-50 parts of a weighting agent, 1-4 parts of a thickening agent, 1-4 parts of a corrosion inhibitor and 1.5-55 parts of water. The acid fracturing system has the characteristics of high density, low corrosion rate, good high-temperature stability, excellent compatibility and the like, and is suitable for acid fracturing transformation of deep high-temperature and high-pressure carbonate reservoirs.

This utility model discloses an acid fracturing fluid mixing device, relating to the field of oil and gas field equipment technology. The device includes a mixing cylinder with a cap at its top. A first motor is fixedly mounted on the top of the cap, and the output end of the first motor passes through the cap and is fixedly connected to a stirring shaft. Stirring blades are fixedly mounted on the circumferential wall of the stirring shaft. A feed branch pipe is fixedly mounted through the top of the mixing cylinder on one side of the first motor. By driving the first and second motors to rotate, the stirring shaft and stirring frame rotate in opposite directions, preventing the raw materials inside the mixing cylinder from flowing in one direction. This allows for faster and more thorough mixing of the raw materials, improving the mixing effect of the acid fracturing fluid. Brake wheels facilitate movement of the mixing device. Clockwise rotation of the screw moves the support base plate downwards, causing the damping pad to contact the ground, ensuring stable parking of the mixing device.

The invention provides a resveratrol fermentation broth separation method, which comprises: (1) carrying out filter pressing treatment on a resveratrol fermentation broth to obtain a second filter residue, the filter pressing treatment comprising carrying out acid pressing on the fermentation broth first and then carrying out alkali pressing, or carrying out alkali pressing on the fermentation broth first and then carrying out acid pressing; (2) carrying out extraction treatment on the second filter residue by adopting an organic solvent to obtain extract liquor; (3) washing the extract to obtain a washing solution; wherein the washing treatment comprises the following steps: sequentially carrying out alkali washing treatment and acid washing treatment on the extracting solution, or sequentially carrying out acid washing treatment and alkali washing treatment on the extracting solution to obtain a washing solution; (4) decoloring and dehydrating the washing solution, and concentrating to obtain a concentrated solution; and (5) carrying out crystallization treatment on the concentrated solution to obtain resveratrol. According to the method, the resveratrol extraction period can be shortened under the condition that a chromatographic method is not used, the cost is reduced, and the purity and the yield of resveratrol are improved.

This invention belongs to the field of oil and gas field development technology, and specifically relates to an acid tank preparation and filtration device. It includes a first installation pipe, a second installation pipe, and an acid preparation and circulation pipeline fixedly installed between the first and second installation pipes. The first and second installation pipes are connected to the acid preparation and circulation pipeline via unions. A first valve and a second valve are respectively installed on the first and second installation pipes. A filter screen is installed inside the acid preparation and circulation pipeline. This invention utilizes the circulation time of the prepared acid solution to filter difficult-to-dissolve chemical materials and other solid particles in the acid tank, saving water used for cleaning the acid tank, reducing the safety risks of cleaning the acid tank, lowering the probability of fracturing trucks running dry, improving the first-time success rate of acid fracturing operations, greatly simplifying the acid tank cleaning process, and providing convenient maintenance and safe filtration operations.

This invention relates to the field of oil and gas field enhancement and stimulation technology, and discloses a method for screening coupling agents for acid fracturing in carbonate rocks based on interfacial film formation to regulate acid-rock reactions. The method first conducts basic physical property tests on different types of coupling agents to evaluate their wettability and spreading ability on carbonate rock surfaces; then, it characterizes the adsorption and film-forming behavior of the coupling agents on the rock surface; it evaluates the compatibility of the coupling agents with different fracturing fluid systems; it analyzes the influence of coupling agent concentration and stirring conditions on the acid-rock reaction rate through acid-rock reaction experiments, and establishes an evaluation index for acid-rock reaction rate control; finally, it conducts reservoir adaptability evaluation under different temperature, mineral composition, and porosity conditions, and comprehensively screens out target coupling agents suitable for acid fracturing operations in carbonate rocks. This invention establishes a systematic coupling agent screening process, which can effectively reduce the acid-rock reaction rate, increase the acid interaction distance, and thus improve the acid fracturing stimulation effect of carbonate reservoirs.

The application discloses a hydrogen sulfide scavenger for acid fracturing and a preparation method thereof, and relates to the technical field of hydrogen sulfide scavengers, and comprises the following raw materials in parts by weight: 30-45 parts of aldehyde compounds, 30-45 parts of alcohol amine compounds, 10-18 parts of diamine bridging agents, 2-6 parts of solubilizing complexing agents, 20-30 parts of solvents and 1-3 parts of catalysts; the aldehyde compounds are divided into A component and B component, wherein the mass ratio of the A component to the B component is 2:1-3:1, the A component is paraformaldehyde, and the B component is at least one of glyoxal or glutaraldehyde. Through optimization of a molecular skeleton and introduction of a hydrophilic group, the hydrogen sulfide scavenger improves sulfur removal capacity and chemical stability in a strong acid environment, has good compatibility with acid liquid, effectively inhibits the generation of acid residues and insoluble precipitates, avoids secondary damage to a formation, and ensures high efficiency and mass transfer performance of the product through a preparation process.

The invention belongs to the technical field of carbonate reservoir transformation, and particularly relates to an acid-resistant cationic polyacrylamide polymer as well as a preparation method and application thereof. The polymer has a structure as shown in a formula (I). The polymer disclosed by the invention is used as an acidic fracturing fluid thickening agent, overcomes the technical problem that a conventional polyacrylamide thickening agent is not resistant to acid and temperature, and can achieve the effect of delaying the corrosion speed of an acid fluid to rock at the same time.

The application relates to the technical field of carbonatite reservoir acid fracturing, and discloses a polymer, a preparation method thereof and a composition for gelled acid. The polymer comprises a structural unit shown in formula A, a structural unit shown in formula B and a structural unit shown in formula C, the viscosity-average molecular weight of the polymer is 5-8 million g / mol, the molecular weight distribution is 3-5, the weight ratio of the structural unit shown in formula A, the structural unit shown in formula B and the structural unit shown in formula C is 1:1.2-1.8:0.1-0.2. When the polymer is used as an acid liquid thickening agent, the polymer has the characteristics of high temperature resistance, shear resistance, low initial viscosity and low gel breaking liquid residue content.

The application provides a heterogeneous reservoir acid fracturing parameter design method and system, the method constructs an acidification reconstruction geometric model for a reservoir to be reconstructed, introduces required acidification section length and section thickness data to calculate acid liquid flow rates in fractures under different construction discharge capacities in combination with fracture attribute data, further considers acid etching reaction rates and mass transfer coefficients to calculate acid concentrations on inner walls of fractures reacted with a reservoir matrix, determines etching widths of natural fracture walls according to attribute parameters of the reservoir matrix, further calculates reservoir etching volumes corresponding to different construction acid amounts and acid etching fracture widths and lengths, finally decides corresponding acid etching fracture conductivity capacities according to a correction principle of an N-K model, and selects optimal acid injection parameters according to preset optimization conditions. By using the scheme, the problems of small calculation scales and complicated operations in the prior art are effectively overcome, analytical solutions are flexibly used in the calculation process, and an acid injection scheme with optimal acid etching effects and conductivity capacities is accurately and efficiently selected.

The application provides a preparation method of a delayed crosslinking agent and an acid fracturing fluid, and the method comprises the following steps: carrying out a chelation reaction on a transition metal substance and a ligand substance in a solvent to obtain the delayed crosslinking agent; the transition metal substance is a zirconium source and a titanium source, the zirconium source is one or more of zirconium nitrate, zirconium sulfate and zirconium oxychloride, and the titanium source is titanium tetrachloride; the ligand substance is at least three of glycerol, lactic acid, triethanolamine, sodium gluconate and sodium citrate; and the mass ratio of the transition metal substance and the ligand substance is 1:1-10. The acid fracturing fluid mainly comprises hydroxypropyl carboxymethyl guar gum, the delayed crosslinking agent and a pH regulator, and can still achieve the delayed crosslinking effect at high temperatures. The fracturing fluid is an acid fracturing fluid with temperature-controlled viscosity release, has the advantages of high-temperature resistance, temperature-controlled crosslinking, low friction drag and low residue, and is suitable for low-permeability oil and gas reservoirs, and solves the problems of clay swelling and migration and high pipe string friction drag.

The invention relates to the technical field of oilfield chemistry, in particular to a glycosyl sulfamic acid betaine type surfactant and a preparation method and application thereof.The glycosyl sulfamic acid betaine type surfactant is prepared according to the following steps that firstly, taurine and sodium methoxide with the required amount are mixed and then react, and a first reactant is obtained; 2, adding a required amount of glucose into the first reactant, and reacting to obtain an intermediate product; and step 3, adding N, N-dimethyl-2, 3-epoxypropyl alkyl ammonium chloride into the intermediate product for reaction, and recovering generated sodium chloride to obtain the glycosyl sulfamic acid betaine type surfactant. The method is easy and convenient to operate, the raw materials are green and degradable, environmental pollution is avoided, the obtained glycosyl sulfamic acid betaine type surfactant is used for preparing the acid fracturing discharge aiding agent, the surface tension of an aqueous solution can be effectively reduced, the technical requirements of the acid fracturing discharge aiding agent can be met, the overall production cost can be reduced, and the method is suitable for industrial production. The acid fracturing device is suitable for acid fracturing operation in different operation environments.

This invention discloses a method for preparing a retarder for acid fracturing. The retarder is obtained by copolymerizing a nonionic water-soluble monomer, a silicon-containing monomer, an organic acid adsorbent monomer, and a hydrophobic monomer in an anhydrous organic solvent. After the reaction, the resulting product is directly used as an additive in the working fluid without the need for separation and drying. The organic acid adsorbent monomer contains an iminodiacetic acid structure, which chelates with Ca on the surface of carbonate rocks. 2+ Stable adsorption; after hydrolysis, the silicon-containing monomers condense with hydroxyl groups on the rock surface to form chemical bonds, while the condensation and cross-linking between silicon and hydroxyl groups construct a multi-layer network structure; the hydrophobic monomer is an allyl polyoxyethylene alkyl ether, which forms a hydrophobic barrier on the adsorption film surface through hydrophobic association. The resulting retarder, through the synergistic effect of four mechanisms—chelation adsorption, chemical bonding, multi-layer film formation, and hydrophobic shielding—can reduce the acid rock reaction rate by more than 90% at 150°C and in 20% hydrochloric acid, making it suitable for high-temperature carbonate rock acid fracturing operations.

The invention discloses an acid fracturing multi-field coupling numerical simulation method based on a cloud-ash interaction reservoir, and relates to the technical field of oil and gas field development, the method comprises the following steps: determining a geologic model of the cloud-ash interaction reservoir in an on-site stratum and three-dimensional stress field distribution according to exploration data; based on the geologic model and the three-dimensional stress field distribution, constructing cloud ash reservoir digital cores in different interaction modes, and obtaining a numerical model corresponding to the geologic model; dividing a numerical model by using the introduced adaptive grid; respectively constructing target control equations based on the numerical model subjected to grid division and physical mechanics and fluid seepage characteristics of the cloud-ash interaction reservoir; establishing a fluid-solid-thermal-chemical multi-field coupling equation based on the target control equation, and executing numerical simulation of acid fracturing by solving the equation; theoretical guidance is provided for acid fracturing site construction of the cloud-ash interaction reservoir, and the blank of acid fracturing numerical simulation methods of the cloud-ash interaction reservoir at home and abroad is filled.

The invention discloses a reservoir fracture-cavity body engraving method and system based on acid fracturing pressure response, and belongs to the technical field of petroleum geological exploration. The method comprises the following steps that communication time is determined on the basis of oil pipe pressure response in an acid fracturing construction curve of an acid fracturing well, and then the extending distance of an artificial fracture within the communication time is obtained; and the distance between the edge of the fracture-cavity body and the shaft crack initiation point under the condition of different seismic tensor attribute threshold values is obtained, the superposition degree is calculated by combining the extending distance of the artificial fracture within the communication time, the optimal seismic tensor attribute threshold value is determined, and the target well fracture-cavity body is engraved according to the optimal seismic tensor attribute threshold value. According to the method, geology and engineering are integrated, fracture-cavity body seismic data and acid fracturing pressure response data can be directly utilized to finely engrave the fracture-cavity body, and a basis is provided for subsequent development scheme decision-making of an oil well.

The invention discloses a carbonate rock acid fracturing effect main control parameter analysis method and system, relates to the technical field of acidification, and solves the problem that main control parameters are difficult to identify in existing carbonate rock acid fracturing effect assessment. Calculating the correlation of each parameter based on the parameter data, and filtering out the parameters with extremely high correlation; executing a random forest algorithm and a recursive elimination algorithm based on the parameters to obtain a first weight and a second weight of the parameters; performing weighted average on the first weight and the second weight to obtain a comprehensive weight of the parameter; selecting parameters according to the comprehensive weight to construct a plurality of schemes, inputting the schemes into a BP neural network to simulate the yield to obtain the correlation between the actual yield and the predicted yield, and selecting the parameters contained in the scheme with the highest correlation as main control parameters of the acid fracturing effect; and analyzing carbonate rock acid fracturing effect master control parameters based on a random forest, recursive elimination and a BP neural network algorithm.

The invention belongs to the technical field of oil and gas field development and oil and gas reservoir transformation, and particularly relates to a compact limestone reservoir atomization acid fracturing sand fracturing composite transformation method. The method mainly comprises the following steps: (1) a supercritical atomization acid fracturing web forming stage; (2) a slug temporary plugging prepad fluid fracture forming stage; (3) a multi-particle-size proppant sand adding stage; and (4) a low-viscosity displacing fluid displacing stage. Based on the fracturing thought of'forming a net first and then forming a seam, temporarily plugging a slug and supporting a multi-scale fracture ', the fracturing fluid has the advantages of strong fluidity, strong penetrability and strong breaking lithology of supercritical carbon dioxide, acid solubility of pre-acid, lasting and effective flow conductivity of sand fracturing and the like, and can be widely applied to compact limestone reservoir transformation; and a complex acid etching-supporting composite crack system is formed, and the flow conductivity of the crack is effectively improved.

Methods for acidizing to enhance acid fracturing with a nonreactive, nonaqueous fracturing fluid. The nonreactive, nonaqueous fracturing fluid contains an acid generating solid that is reactive when hydrolyzed. Various embodiments described herein include methods for acid stimulation on the surfaces of a reservoir. Acid stimulation methods can comprise: injecting a nonaqueous fracturing fluid into a reservoir; wherein the nonaqueous fluid comprises an acid-generating solid and a lubricant; forming new fractures, cracks, or breaks within the reservoir with the nonaqueous fluid and introducing a non-reactive aqueous fluid; releasing the acid-generating solid in situ to generate a produced acid; and etching the face of a rock surface of the reservoir with the produced acid.

The invention discloses an ultra-deep fractured carbonate rock acidification acid injection discharge capacity optimization method, which comprises the following steps: S1, obtaining the width of a natural fracture according to the elevation distribution of the natural fracture of an underground rock core, and obtaining the width of the coarsened natural fracture after discretization; s2, constructing a model considering fracture normal deformation, and correcting the roughened natural fracture width; s3, constructing a temperature-hydraulic-chemical three-field coupling acid etching hydraulic fracture model, and calculating the acid etching fracture width based on the fracture width obtained in the step S2 after the normal deformation of the fracture is considered; and S4, carrying out simulation calculation under different acid injection rate conditions, and preferably selecting the acid injection displacement according to the dimensionless comprehensive transformation coefficient. According to the method, the influence of closed stress and multiple heat effects is considered when the acid etching process of the ultra-deep fractured carbonate rock is simulated, and the influence of the effective action distance of acid liquor and the width of an acid etching seam on the transformation effect can be quantitatively and comprehensively considered when the acid injection displacement is optimized; and a means is provided for the design of an acid fracturing transformation scheme of the ultra-deep crack type carbonate reservoir.

The invention belongs to the technical field of fracture acidizing of oil and gas field development, and discloses a testing device and a testing method for evaluating acid etching fracture parameters. The testing device comprises an acid rock reaction system and a sampling system, wherein the acid rock reaction system comprises a plurality of clamping devices, a movable nuclear magnetic scanning device and a constant temperature device; the plurality of clamping devices are sequentially arranged in series, are used for clamping rock samples, and are respectively arranged in corresponding position intervals of different reservoir areas in the constant temperature device; the movable nuclear magnetic scanning device is arranged outside the clamping device; and the outlet end of the holder in the acid rock reaction system is connected with the sampling system. The testing device can simulate the acid fracturing action process of different reservoir positions under the reservoir condition and obtain the acid etching fracture parameters of different positions, so that the seepage capacity of the acid etching fractures of different reservoir positions is simulated and evaluated, and the effectiveness of the acid etching fractures is evaluated.

Provided in the present application are a true triaxial acid fracturing physical simulation and conductivity integrated synchronous test device and a method. The device comprises: a clamping module, comprising a clamping holder, an X-axis assembly, a Y-axis assembly, a Z-axis assembly and a perfluoroelastomer sleeve; a seepage module, comprising a simulated wellbore; and a monitoring module, used for monitoring the flow rate of an acid fracturing fluid, the fluid distribution in a core, and the morphology and conductivity of acid-etched fractures or hydraulic fractures. At least one surface of the X-axis assembly, the Y-axis assembly and the Z-axis assembly is in close contact with the inner side of the perfluoroelastomer sleeve, and the clamping module is configured to, under the drive of a servo module, change liquid chambers of the X-axis assembly, the Y-axis assembly and the Z-axis assembly, so as to squeeze a core wrapped in the perfluoroelastomer sleeve. The described configuration can achieve integrated monitoring of the fluid distribution in a core and the morphology and conductivity of acid-etched fractures or hydraulic fractures, and also reduce adverse effects caused by stress concentration, so as to improve the accuracy of tests.

This invention discloses a method, system, storage medium, and equipment for diagnosing communication issues during acid fracturing in fractured-vuggy carbonate reservoirs, belonging to the field of reservoir stimulation technology. The method includes: establishing a bottomhole pressure calculation model; collecting geomechanical parameters, reservoir parameters, communication characteristic parameters during acid fracturing, and fracture-vuggy body parameters from previously stimulated wells in the work area, establishing and training a first neural network model to obtain a prediction model for the communication parameters of fracture-vuggy bodies during acid fracturing; collecting geomechanical parameters and reservoir parameters from the target well, and real-time acquiring the communication characteristic parameters during acid fracturing of the target well to construct a real-time dataset; and substituting the real-time dataset into the prediction model to calculate the communication parameters of fracture-vuggy bodies during acid fracturing. This invention employs integrated monitoring technology and data analysis algorithms, enabling real-time monitoring and diagnosis of communication issues during reservoir acid fracturing, providing a basis for decision-making during construction, and improving construction efficiency and reservoir stimulation effectiveness.

The invention discloses an enhanced gas extraction system based on dual-pulsation and acid fracturing permeability enhancement for a low-permeability coal seam, including an overpressure protection mechanism, a fracturing liquid delivery line, a gas extraction line, a mixing tank, a pressure control and monitoring mechanism and a frequency adjustment and monitoring mechanism. The invention further discloses an enhanced gas extraction method based on dual-pulsation and acid fracturing permeability enhancement for a low-permeability coal seam. The invention has the advantages of enhancing the connectivity between fracture-pore structures in coal, improving the permeability enhancement effect on a coal seam, and improving the gas extraction efficiency of the coal seam.

This invention discloses a high-temperature acid-responsive degradable microencapsulated acid for acid fracturing and its preparation method, belonging to the technical field of chemical materials for acid fracturing in oil and gas fields. The high-temperature acid-responsive degradable microencapsulated acid for acid fracturing includes an acid core and a microcapsule shell encapsulating the acid core. The microcapsule shell is made of a high-temperature acid-responsive degradable polymer material, which is polymerized from five monomers: acrylamide, tert-butyl methacrylate, 2-acrylamide-2-methylpropanesulfonic acid, diallylamine, and allyl polyoxyethylene ether. The microencapsulated acid of this invention can achieve delayed acid release and shell degradation in high-temperature acid solutions, effectively reducing reservoir damage caused by shell residue while ensuring etching capability. It also exhibits strong temperature and shear resistance, making it suitable for acid fracturing operations in high-temperature / ultra-high-temperature carbonate reservoirs.

1. Name of the product in this design: Dual-machine dual-pump acidification skid. 2. Purpose of this design: for use in oilfield acid fracturing operations. 3. The key design feature of this product is its shape. 4. The image or photograph that best illustrates the design's key points: a 3D model.