1287 results about "Shale gas" patented technology

The invention relates to the technical field of data acquisition and data analysis, in particular to a hydraulic fracturing test crack propagation monitoring system which comprises a monitoring system and is used for monitoring crack propagation behaviors in the hydraulic fracturing process in real time. Constant or dynamically changing confining pressure and axial pressure are provided; the pore pressure dynamic regulation and control unit is used for accurately controlling the injection pressure, flow and saturation of fracturing fluid and simulating fracture propagation behaviors under different seepage conditions; the multi-physics field sensing monitoring network unit is used for collecting strain, sound wave signals and a surface displacement field in the crack expansion process in real time; full-scale monitoring of rock fracture propagation is realized, an influence mechanism of pore pressure and time effect on fracture evolution is disclosed, an accurate prediction means is provided for shale gas development and deep engineering, and the fracturing effect and engineering safety are remarkably improved.

The invention relates to the technical field of fracture network fracture water channel identification, and discloses an identification method for analyzing a dominant flow channel in a three-dimensional fracture network based on a topological network. According to the method, probability distribution parameters such as geometric occurrence, gap width and density of a rock mass multi-scale fracture system in a target area are obtained through field surveying and mapping and three-dimensional scanning, and a spatial topological structure of the three-dimensional fracture system is reconstructed by adopting Monte Carlo method simulation and discrete fracture network modeling technology; secondly, abstracting the fracture network into a three-dimensional topological graph model based on a graph theory principle, defining fracture center points and cross points as graph nodes, and converting fracture sections into weighted edges; the method breaks through the continuous medium hypothesis limitation of traditional seepage analysis, and has important engineering application value in the fields of deep geological energy storage reservoir seepage risk assessment, shale gas fracture network optimization design, rock slope stability analysis and the like; compared with a traditional numerical simulation method, the method has the technical advantages of being high in calculation efficiency, good in prediction precision, high in multi-scale applicability and the like.

The invention discloses a geological modeling, crack propagation and fluid-solid coupling production prediction integrated evaluation method, and relates to the field of multiple technologies, and the method comprises the steps: constructing a three-dimensional geological model of a deep shale gas reservoir; according to the construction model, the attribute model, the three-dimensional ground stress model and the rock mechanical parameter model, a hydraulic fracture model is constructed; based on the hydraulic fracture model and the three-dimensional geological model of the deep shale gas reservoir, establishing a fluid-solid coupling productivity simulation mathematical model of the deep shale gas reservoir; according to the fluid-solid coupling productivity simulation mathematical model of the deep shale gas reservoir, the fractured horizontal well yield of the shale gas reservoir is predicted, and a prediction result is comprehensively evaluated and optimized. According to the method, multiple links of geological modeling, fracture propagation simulation, fluid-solid coupling production prediction and the like are integrated, and the geological characteristics of the gas reservoir, the fracture propagation rule and the interaction between fluid flow and solid deformation are comprehensively considered, so that comprehensive evaluation and optimal development of the deep shale gas reservoir are realized.

The invention relates to the technical field of shale gas storage development and yield increase, in particular to a shale gas refracturing potential prediction method and system based on multi-modal data fusion. A data set is established according to the obtained shale gas well data, the data set comprises a multi-dimensional sequence data set and a single-valued data set, the multi-dimensional sequence data set comprises logging curve data and fracturing construction curve data, and the single-valued data set comprises geological data, reservoir physical property data, initial fracturing parameter data, production dynamic data and rock mechanics data; marking the refracturing potential of the well section through the production dynamic data; performing data cleaning and standardization processing, and dividing a data set into a training set, a test set and a verification set; and constructing a shale gas refracturing potential prediction model which meets a preset requirement and takes the multi-dimensional sequence data set and the single-valued data set as input and the refracturing effect type as output. According to the method, efficient prediction of the overall refracturing potential of the shale gas well can be realized.

The invention discloses a shale gas well middle and later period effusion intelligent diagnosis method based on LSTM and TCN models. The method comprises the following steps: S1, collecting and preprocessing multi-source time sequence data, performing sliding window segmentation, and generating a standardized data set; s2, manually marking an effusion starting point, a critical point and a process intervention point, and generating a training sample set with a label; s3, performing multi-layer expansion causal convolution on the time sequence convolutional network, and extracting multi-scale local features; s4, the modeling of the long-short-term memory network is globally dependent, and output diagnosis and early warning are discriminated; and S5, regularly collecting newly added data and diagnosis results, dynamically updating the sample set, and retraining and optimizing the model. According to the method, intelligent, efficient and real-time diagnosis and early warning of the liquid accumulation state in the middle and later periods of the shale gas well are achieved.

The invention relates to a shale gas multi-layer stacked reservoir dessert evaluation and separate layer fracturing decision-making method, and belongs to the technical field of oil-gas field development, and the method comprises the following steps: calculating porosity, adsorbed gas content, organic carbon content and vitrinite reflectance geological parameters; calculating brittleness index and fracture toughness engineering parameters; carrying out normalization processing and weight distribution by adopting a CRITIC weight method, constructing a geological-engineering comprehensive evaluation model, and dividing four types of sweet spot areas; through a mixed method of main parameter priority and abnormal value verification, preferentially analyzing interlayer gradients of high-weight parameters, and performing local fine verification on abnormal abrupt change of low-weight parameters based on a 3 sigma principle; and in combination with a rigid-flexible layering model, a fracturing layering strategy is dynamically decided, and the complexity of the fracture network is optimized. According to the method, the reservoir identification precision is improved through multi-parameter fusion evaluation, the fracturing efficiency is enhanced through dynamic hierarchical decision, the development cost is finally reduced, and technical support is provided for efficient development of shale gas.

The invention discloses a construction parameter optimization method and device based on dessert prediction, a medium and equipment, and the method comprises the steps: obtaining a data set of a shale gas well production process, and determining a dessert indication factor; training a network model by taking the data set as input and the dessert indication factor as output to obtain a dessert indication factor prediction model; optimizing the dessert indicator factor prediction model by using a Bayesian hyper-parameter optimization algorithm, and inputting a data set obtained in real time into the optimized dessert indicator factor prediction model to obtain a prediction result; inverting a prediction result into three-dimensional space distribution characteristics of desserts in the shale reservoir; and determining contribution values and partial dependency relationships of the plurality of geological parameters and the plurality of engineering parameters to a prediction result based on the three-dimensional space distribution characteristics, deploying construction parameters according to the contribution values and the partial dependency relationships, and synchronously updating a sweet spot indication factor prediction result to realize spatial dynamic optimization and adjustment of the construction scheme. Through the scheme, the construction parameters can be scientifically optimized.

The invention discloses a water injection induced earthquake monitoring and fault activation detection system, and belongs to the field of earthquake monitoring and fault activation detection. The earthquake observation module is used for obtaining earthquake monitoring data; the seismic phase data extraction module is used for carrying out micro-seismic identification according to the seismic monitoring data to obtain seismic phase data; the earthquake initial positioning module is used for obtaining an earthquake directory of initial positioning; the earthquake fine positioning module is used for carrying out secondary positioning to obtain an earthquake directory of fine positioning; the fault and structure modeling module is used for integrating the finely positioned seismic catalog into a three-dimensional geologic structure model and carrying out spatial positioning and visualization of seismic activities; and the fault activation and earthquake risk analysis module is used for analyzing the earthquake activity time change trend, b value change, fault activation and earthquake risk according to the three-dimensional geologic structure model. The method solves the problem that an existing method lacks monitoring of fault activation and weakening of the shale gas development area and water injection induced earthquakes.

The invention provides a high and low temperature true triaxial fracturing, seepage and microscopic monitoring experiment system and method. The system comprises a three-dimensional model and a reaction kettle module, the triaxial stress loading module is arranged at the bottom and the periphery of the cavity of the three-dimensional model and reaction kettle module; a fracturing module; a temperature control module; and a crack monitoring module. Through internal and external integral temperature control, large-range temperature adjustment and stable control of-15 DEG C to 130 DEG C are realized; monitoring points such as acoustic emission, resistivity and the like are carried to explain and analyze the dynamic change rule of the crack in real time; through the innovative structural design of the device, the functions of kettle body sealing, high-stress-difference triaxial synchronous loading, radial uniform seepage and the like are achieved, the experimental requirements of hydrate in-situ generation and decomposition, large-size rock sample saturation, high-stress-difference fracturing experiments and the like are met, the true-triaxial large-physical-model experimental application scene is expanded, and the experimental efficiency is improved. And technical support is provided for fracturing transformation process optimization, scheme design and the like of unconventional oil and gas resources such as deep shale gas and hydrates.

The invention belongs to the technical field of petroleum engineering, and discloses a shale gas reservoir apparent permeability prediction method and a related device, and the method comprises the steps: obtaining data; judging a gas flow state; establishing a shale gas mass migration model; establishing apparent permeability models of capillary tubes with different sizes; obtaining a shale reservoir apparent permeability model; carrying out transfer learning; according to the method, the influence of the reservoir effective stress and the shale water saturation on the permeability is comprehensively considered, the neural network model is adopted to obtain the effective flow radius, and the prediction accuracy is improved; by introducing the permeability correction coefficient, dynamic correction of the original permeability value is realized, so that the actual permeability can be reflected more accurately; according to the method, by adopting transfer learning, a specific type of shale reservoir apparent permeability model is transferred to other conditions, so that the model can be used for predicting the permeability of different types of shale reservoirs, and the universality is effectively improved.

The invention discloses a shale hydrocarbon expulsion efficiency evaluation method, device, equipment and medium, and relates to the technical field of shale gas exploration and developing.The shale hydrocarbon expulsion efficiency evaluation method includes the steps that hydrocarbon generation quantity charts of shale under different total organic carbon TOC grades are constructed; testing the water saturation of the core sample of the shale to obtain the water saturation rate of the core sample; carrying out oil washing treatment on the rock core sample, and carrying out porosity test to obtain rock porosity and rock apparent density; obtaining a crude oil sample of a production layer where the core sample is located, and performing a crude oil physical property experiment to obtain crude oil density; when key parameters such as water saturation rate, rock porosity, rock apparent density, crude oil density and shale hydrocarbon generation quantity charts under different total organic carbon TOC grades of a core sample and key parameters of hydrocarbon release and migration in a hydrocarbon expulsion process are measured, a dynamic measurement process is adopted, and the dynamic measurement process can realize dynamic simulation of a hydrocarbon migration path; and finally, accurate evaluation of the shale hydrocarbon expulsion efficiency is realized.

The invention relates to the technical field of carbon dioxide sequestration and shale gas development, and particularly discloses a shale micro-nano pore multiphase multicomponent competitive adsorption data determination method and device, and the method comprises the steps: obtaining a shale core sample of a target area, and determining the type and relative content change characteristics of surface functional groups of the shale core sample; key structures and force field parameters of shale clay minerals in a target block are collected, and a shale clay mineral molecular model is established; establishing a plurality of fluid molecular models; establishing slit models, and establishing a multiphase fluid system model between the slit models to obtain a stable configuration; applying an external electric field to the stable configuration, and performing molecular dynamics calculation to obtain molecular trajectory coordinates and dynamics information of the multi-phase multi-component fluid; and calculating competitive adsorption data of the shale micro-nano pore multi-phase multi-component fluid under the action of the electric field. According to the scheme, the occurrence state and the competitive adsorption behavior of the shale micro-nano pore multi-phase multi-component fluid under the action of the electric field can be disclosed from the molecular scale.

Embodiments of the present invention relate to the technical field of shale gas development, and provide a method and system for predicting the maximum horizontal principal stress of shale gas reservoirs. The method comprises: performing cross-arranged gather extraction on acquired original shot gathers to obtain corresponding OVT gathers, and preprocessing the OVT gathers; acquiring well logging data, performing well-to-seismic calibration and seismic horizon interpretation on the basis of the well logging data, and obtaining an interpreted horizon of the current reservoir that meets in-situ stress prediction as a target horizon; constructing a low-frequency model on the basis of the well logging data and the target horizon, and calculating a Poisson's ratio and a fracture density on the basis of the low-frequency model; calculating a vertical principal stress of the target horizon on the basis of a velocity field, a formation density and a density inversion body; and calculating the maximum horizontal principal stress of the current reservoir on the basis of the Poisson's ratio, the fracture density, the vertical principal stress and a preset principal stress solving model. The solution of the present invention solves the problem of low accuracy in existing solutions for predicting the maximum horizontal principal stress of shale gas reservoirs.

The utility model discloses an integrated skid-mounted device of double vertical sand removers, which relates to the technical field of shale gas sand removal and comprises a skid-mounted base, a sand remover body and a process pipeline connected with the sand remover body, a gas inlet is arranged at the upper end of the sand remover, a gas outlet is arranged at the lower end of the sand remover, and a drain outlet is arranged at the bottom of the sand remover. The two vertical sand removers are parallelly suspended on the prying base, the sand removers are provided with maintenance platforms, and the maintenance platforms are provided with ladders and guardrails; the process pipeline comprises a gas inlet pipeline and a gas outlet pipeline; one end of the gas inlet pipeline is connected with a gas inlet of a high-layer desander; the other end of the gas inlet pipeline is connected with a low prying base in parallel; one end of the gas outlet pipeline is connected with a gas outlet of the high-layer desander and the other end of the gas outlet pipeline is connected with the low prying base in parallel; one end of the blow-off pipeline is connected with a blow-off port of the high-layer desander, and the other end of the blow-off pipeline is connected with the low prying base in parallel. The desander can be used for desanding efficiently, and is high in integration level, simple to mount and easy to carry.

The invention discloses a shale gas well dessert prediction method and device based on integrated learning. The method comprises the steps of obtaining main control factors and feature data of a shale gas well to be predicted, and inputting the main control factors and the feature data into a trained dessert prediction model to obtain dessert prediction data; the model training process comprises the following steps: determining main control factors influencing the dessert according to the correlation between each parameter in the prediction data of the sampled shale gas well in the target area and the dessert; the prediction data comprises first data and second data, the first data comprises geological data, perforation data and oil and gas production data, and the second data comprises logging data and fracturing construction data; performing feature extraction on each parameter in the second data to obtain feature data; constructing a training data set according to the main control factors and the characteristic data of the shale gas well; and training the dessert prediction model based on the training data set. The accuracy of a prediction result can be improved, and fracturing design is effectively guided.

The invention relates to the technical field of oil development, in particular to a shale oil and gas fracturing sliding sleeve capable of being opened and closed repeatedly and a using method. According to the technical scheme, a central pipe fracturing liquid inlet is formed in the upper side of a central pipe, and a reversing rail is arranged on the surface of the outer wall of the middle; a sealing cylinder sleeve and a one-way circulating valve carrier are sleeved outside the central pipe, a fracturing piston, a swivel pressing cap and a reset spring are installed in an annulus, a constant-pressure opening cavity is formed in the inner wall of the fracturing piston, a swivel is installed in the swivel pressing cap, a track pin is installed in the swivel, and the position is moved along a reversing track on the surface of the outer wall of the central pipe through the track pin. The fracturing piston moves downwards to the position of the cylinder sleeve fracturing liquid outlet under the action of pressure, the fracturing function is started, fracturing liquid is sprayed out along the cylinder sleeve fracturing liquid outlet to enter a target fracturing layer, fracturing construction of a plurality of fracturing layers can be achieved through multiple times of fracturing liquid injection and injection stopping, the fracturing sliding sleeve can be repeatedly opened and closed, and the fracturing construction efficiency is improved. And fracturing construction requirements of shale oil and gas with different layers can be met.

The invention provides a shale gas reservoir pressure fracture network expansion numerical simulation method, which comprises the following steps of: performing multi-layer coring scanning on a shale gas reservoir, and constructing a three-dimensional digital core model; constructing digital core flow numerical simulation by adopting a lattice Boltzmann method to obtain flow physical parameters; constructing digital rock core strain simulation by adopting a finite element method to obtain rock mechanical parameters; establishing a shale gas reservoir complex fracture network expansion mathematical model by considering a fluid-solid coupling effect, and constructing a numerical solution algorithm by combining a finite element method and a finite volume method; constructing a quantitative characterization method for the shape of the fracture network after pressing, and evaluating the size and complexity of the transformed fracture network; the method fills the gap of fracturing simulation technology research, and has the characteristics of high calculation precision, short calculation period and low cost.

The invention provides a method for preferably selecting a shale gas structure storage favorable area not based on formation pressure. The method comprises the steps that a target research area is selected, and a core exploration target layer series is determined; on the basis of a target stratum shale gas preservation mechanism, core parameters independent of stratum pressure data are screened, and a comprehensive evaluation index system containing target stratum self-sealing performance, regional cover stratum conditions and structural transformation action parameters is constructed; spatial distribution analysis is carried out on each parameter, grading is carried out according to geological laws and adjacent region experience, and weight coefficients are distributed according to the influence degree of the parameters on storage conditions; obtaining a comprehensive score of the structure storage condition of each evaluation unit through grade assignment and weighted stacking calculation; and delineating a shale gas structure storage favorable area according to the comprehensive score. The method is suitable for low-exploration-degree areas with complex structures, sparse drilling wells or lack of formation pressure data, and has the advantages of objective evaluation, high operability and high practical value.

The present invention belongs to the field of shale gas technology, and in particular to a shale gas rapid desorption test device and method. Aiming at the problem that shale gas molecules have strong adsorption force and are difficult to desorb, and the shale itself has low permeability, resulting in a long experimental time for shale gas desorption test, the following scheme is proposed, including a main box, wherein a crushing and screening module is arranged inside the main box, and the crushing and screening module includes a base and a fixed cylinder, the base and the fixed cylinder are fixedly connected to the bottom inner wall of the main box, the inner wall of the fixed cylinder is slidably connected to a mounting cylinder, an acceleration module is arranged on the mounting cylinder, and a tray is fixedly connected to the bottom inner wall of the mounting cylinder. A shale gas rapid desorption test device and method disclosed by the present invention can make shale sample particles vibrate in the vertical direction during desorption, and at the same time, stirring with a stirring paddle can make the gas inside the shale sample more fully contact the desorption environment, thereby accelerating the desorption process.

The utility model provides a cable tensile strength testing device, and relates to the technical field of deep shale gas horizontal well fracturing. The first clamping and fixing mechanism is used for clamping and fixing a ferrule structure of the tested cable, and the ferrule structure is formed by bending one end of the cable into an arc-shaped closed loop; the rope sleeving column is transversely connected to the base in a sliding mode, and the loop structure can be connected to the rope sleeving column in a sleeving mode; the tension detection mechanism comprises a tension detector, one end of the tension detector is connected with the rope sleeving column, and the other end of the tension detector is connected with the base; the winding mechanism comprises a winding roller and a driving motor which are in transmission connection, the winding roller is installed on the base, and a containing groove is formed in the side wall of the winding roller; and the second clamping mechanism is arranged in the accommodating groove and is used for clamping and fixing the other end of the cable. And through the arrangement of the winding roller, the cable can be pulled, and the device can adapt to cables with different lengths.

The invention relates to a shale gas well oil pipe size optimization method considering liquid accumulation influence. The problems of serious liquid accumulation influence, difficulty in optimizing the size of an oil pipe and the like in the whole production period of the shale gas well are solved; according to the technical scheme, according to a wellbore pressure drop calculation method considering the liquid accumulation influence, the daily wellbore pressure drop and the liquid accumulation amount of oil pipes of different sizes in the whole production cycle of a gas well are predicted, the influence of the wellbore pressure drop and the liquid accumulation amount in the whole production cycle is comprehensively considered, and the comprehensive utility value of the oil pipes of different sizes is obtained through calculation. By comparing the comprehensive utility values of the oil pipes with different sizes, the optimal oil pipe size is optimized; according to the shale gas well oil pipe size optimization method considering the liquid accumulation influence, the influence of the change of the liquid production capacity of the shale gas well in the whole production period on the oil pipe liquid accumulation is considered, and efficient and stable production of the shale gas well in the whole production period is promoted.

The invention belongs to the technical field of oil and gas well development, and particularly relates to a shale gas well gas lift dredging method. According to the method, the gas lift pressure is obviously reduced to 40-60% through comprehensive means such as foam drainage liquid filling for reducing the gas well accumulated liquid density, short-time annular gas lift, wellhead return pressure reduction for the gas lift, oil jacket pressure balancing for reducing the hydrostatic liquid column height and alternate positive and negative lift, and multiple cooperation is conducted, so that the gas lift pressure is obviously reduced to 40-60%, the gas well recovery production progress can be accelerated, the gas lift effect is improved, and the gas well recovery efficiency is improved. The production recovery cost is reduced. In the process of lifting the deep shale gas well, gas well lifting can be achieved by optimizing gas lifting operation steps on the basis of existing gas lifting equipment, effective gas lifting can be achieved by means of the technical method under the influence of factors such as high temperature and high pressure, shaft corrosion and sand production of the deep shale gas well under different conditions, and the success rate reaches up to 80%.

The invention relates to the technical field of drilling compositions, in particular to a composite plugging agent, a plugging composition and plugging cement paste for shale gas formation cracks. The composite plugging agent for shale gas stratum cracks is composed of a bridging material, a filling material and an end-capping material, the mass ratio of the bridging material to the filling material to the end-capping material is (1.2-1.4): 0.5: (0.1-0.3), the bridging material is organic fibers with the length of 3-5 mm, the filling material is composed of inert particles with the particle size of 35-280 [mu] m and micro-silicon with the particle size of 0.15-1 [mu] m, and the end-capping material is a mixture of silicon oxide and silicon oxide. The end-capping material is composed of organic fibers with the length of 8-9 mm and walnut shells with the particle size of 3-5 mm. Through compounding of different types of bridging materials, filling materials and end sealing materials and grading of fibers with different lengths and plugging particles with different particle sizes, the plugging agent can be matched with cement paste in complex cracks and large cracks (1-4 mm) of a stratum to form a stable and compact plugging layer, the compressive strength is high, effective retention is achieved, and the effect of plugging a complex leakage layer is achieved.

The invention discloses a low-frequency model building method and device, equipment and a medium, and relates to the field of seismic data inversion and reservoir prediction, and the method comprises the steps: obtaining underground near-bit engineering parameters, carrying out the motion characteristic analysis and excitation characteristic analysis of the underground near-bit engineering parameters, and obtaining the motion characteristics of a shaft bottom drilling tool and the excitation characteristics of bit pressure and torque; establishing an initial drill bit-drill string system dynamic control equation by using the motion characteristics of the well bottom drilling tool and the bit pressure torque excitation characteristics, and performing parameter correction and supplementation on the initial drill bit-drill string system dynamic control equation to obtain a target drill bit-drill string system dynamic control equation; and solving the dynamic control equation of the target drill bit-drill string system to obtain a dynamic response value, and identifying and analyzing the motion state of the underground drilling tool based on the dynamic response value. According to the method, the accuracy of state recognition of the underground drilling tool can be improved, so that the profit level of a long horizontal section shale gas drilling single well is improved, the well building period is shortened, and the drilling cost is reduced.

The invention discloses a shale gas well fracturing parameter optimization design method and system based on a depth Q network, and relates to the technical field of shale gas development, and the method comprises the following steps: S1, collecting geological parameters, fracturing construction parameters and productivity data of a shale gas well in advance; s2, constructing an agent model and performing environment simulation; and S3, constructing a DQN model. According to the method, a LightGBM algorithm is adopted to construct a data-driven proxy model to simulate a real fracturing environment, an optimization model is constructed based on a deep Q network (DQN), state, action, reward and epsilon-greedy strategies are defined, and technologies such as a variable step size search mechanism, experience playback and target network soft update are combined, so that the real fracturing environment is simulated. The problems that a traditional optimization method is weak in local search capability and low in convergence speed are effectively solved, multivariable synchronous optimization of the unit perforation length proppant dosage and the fracturing fluid dosage is achieved, and a global optimal parameter combination can be rapidly explored.

The invention discloses a shale gas full life cycle yield prediction method, and relates to the field of shale gas development. According to the shale gas full life cycle yield prediction method, the production stage of a shale gas well is divided into six stages of stable yield, continuous decreasing, intermittent production, pressurization decreasing, pressurization intermittent opening and fracturing effect receiving; in the stable production stage, the gas production rate is predicted by adopting a productivity coefficient method based on unstable linear flow, in the continuous decline stage, the gas production rate is predicted according to the ARPS decline model analogy partition decline rate, and in the intermittent production stage, the gas production rate is predicted by combining the ARPS decline model and the intermittent efficiency; in the pressurization decline stage, the gas production rate is predicted according to the gas well decline rate of the corresponding decline stage by adopting monthly production data; the gas production rate is predicted in combination with a decline model and the intermittent opening efficiency in the pressurizing intermittent opening stage; and predicting the gas production rate by using the effected ARPS model in the fracturing effected stage. According to the shale gas full life cycle yield prediction method, the corresponding yield prediction method is established according to the production rules of different development stages of the shale gas full life cycle, and the yield prediction efficiency and accuracy are improved.

The invention provides a composite synergistic system for a shale gas old well and an immovable string production increasing process. The composite synergistic system mainly comprises the following substances: 10-12% of a wetting improver; 4%-6% of a scale remover; 2%-3% of a scale inhibition dispersant; 5%-10% of a resistance-reducing discharge aiding agent; 15%-20% of a synergistic accelerant; the wetting improver is a mixture of alkyl polyglucoside, an anionic surfactant sodium dodecyl benzene sulfonate and deionized water, the content of the alkyl polyglucoside in the wetting improver is 5%-10%, and the content of the anionic surfactant sodium dodecyl benzene sulfonate is 15%-18%; the descaling agent is a mixture of sodium alpha-olefin sulfonate and nonylphenol polyoxyethylene ether ammonium sulfate, and the mass ratio of the sodium alpha-olefin sulfonate to the nonylphenol polyoxyethylene ether ammonium sulfate in the descaling agent is (2: 1)-(3: 1). According to the composite synergistic system, through combination and reuse of different materials and different doses, the multifunctional composite synergistic system integrating vibration, permeation and dispersion effects is researched and developed, and therefore immovable tubular column yield increase construction of a shale gas old well is achieved.

The invention belongs to the technical field of petroleum and natural gas exploration and development, and particularly relates to a coiled tubing bottom seal dragging pressure testing and leakage finding packer and a using method thereof, and the pressure testing and leakage finding packer comprises an upper centralizer, a pressure balancing mechanism, a setting packing mechanism and a lower centralizer which are coaxially and sequentially connected in a threaded mode. The pressure balance mechanism comprises a sleeve shell assembly and a pressure relief assembly. A pressure relief opening is formed in the side face of the sleeve shell assembly, and the pressure relief assembly is arranged in the sleeve shell assembly. The setting packing mechanism comprises a central pipe; a rubber sleeve assembly, a slip assembly and a centralizing assembly are sequentially installed on the basis of the center pipe from top to bottom, the rubber sleeve assembly is movably connected with the center pipe in an axial limiting mode, the slip assembly is fixedly connected with the centralizing assembly, and the centralizing assembly is movably connected with the center pipe based on the track pipe groove. According to the technical scheme, pressure bearing reasons and leakage point positions which cannot be found out by dragging pressure testing for multiple times in one-time well entering can be achieved, and it is guaranteed that follow-up fracturing construction operation of the shale gas well is safely and efficiently carried out.

The invention provides a method for determining the residual yield of shale gas based on methane carbon isotope change in desorption gas. The method comprises the following steps: S1, putting a shale sample into a desorption tank filled with saturated salt water, and sealing; s2, placing the desorption tank in water, recording the volume of desorption gas according to the desorption time by using a drainage method, and collecting the desorption gas; s3, according to the analytic gas collected in each analytic time period, calculating accumulated total analytic gas, and calculating the proportion of the analytic gas in each analytic time period to the total analytic gas to obtain a stage accumulated analytic rate; s4, measuring the ratio of methane carbon isotope delta 13C in the desorption gas when the desorption rate is accumulated in each stage; and S5, establishing a change curve of the stage cumulative analysis rate of the shale gas and the methane carbon isotope delta13C so as to obtain a model for predicting the shale gas productivity stage. The invention provides a non-destructive and direct gas potential measurement means, which is high in accuracy and can be well adapted to shale gas prediction.

The invention relates to a sterilizing, corrosion-inhibiting and scale-inhibiting foaming agent for foam drainage and a preparation method thereof, and belongs to the technical field of oil and gas development. The sterilizing, corrosion-inhibiting and scale-inhibiting foaming agent comprises the following components in percentage by mass: 1%-2% of a triazole bactericide, 3%-5% of a scale inhibitor, 0.2%-1% of polyvinyl alcohol, 10%-18% of a bis-imidazoline sulfonated quaternary ammonium salt zwitterionic surfactant, 5%-10% of benzene sulfonate, 5%-10% of Ninol and the balance of water. The foaming agent is good in foaming performance, the prepared foam liquid is stable in foam, very high in liquid carrying capacity and good in salt resistance, temperature resistance and oil resistance, compared with a foaming agent in the prior art, the foaming agent is better in performance, and the foaming agent is suitable for different oil and gas wells, shale gas wells and other environments. And besides foaming performance, the detergent also has excellent sterilization, corrosion inhibition and scale inhibition effects, realizes multiple effects by one agent, and is very strong in comprehensive performance.