239 results about "Pellets" patented technology

The invention discloses a multifunctional geotechnical mechanical testing system for controlling temperature, humidity and salinity in an extreme environment, and relates to the technical field of ocean geotechnical engineering and geotechnical engineering. The system integrates a high-precision temperature and humidity and salinity control system, can accurately simulate the influence of complex environments such as extreme temperature and humidity, salt spray corrosion and the like on the mechanical properties of geotechnical materials, supports a direct shear test, a pull-out test, a soil body single-particle crushing test and a geosynthetic material stretching and puncturing test, can distinguish static, dynamic and long-term creep test modes, and can be used for testing the mechanical properties of the geotechnical materials. Comprising creep mechanical property testing under cyclic direct shear and continuous load. A visual monitoring assembly is additionally arranged, so that the microscopic deformation and damage process of the sample can be recorded in real time. Through multifunctional integration, temperature, humidity and salinity joint control, visual monitoring and dynamic and static coupling test devices, the technical bottlenecks of single function, environment simulation limitation and microcosmic observation deficiency of traditional equipment are solved, and high engineering application value and popularization potential are achieved.

The invention belongs to the technical field of geological sample analysis, and particularly relates to a heavy mineral fidelity pretreatment and morphology automatic characterization method based on artificial intelligence. The method is based on a medium-low hardness heavy mineral fidelity separation and purification technology, an integrated multifunctional target manufacturing technology, a microscopic image intelligent acquisition technology and intelligent identification and feature extraction based on deep learning. The method comprises the following steps: acquiring fidelity heavy mineral particles which maintain the original three-dimensional morphology, are not reset in internal thermosensitive geological records and are not subjected to any systematic deviation screening on population composition, calculating a series of morphological parameters such as an extension coefficient, roundness, color and the like of each heavy mineral particle, and finally outputting a structured quantitative data report. According to the method, multidirectional and intelligent fidelity is realized from the source, and the analysis flux and objectivity are greatly improved by an automatic process, so that systematic and quantitative mineral resource general survey on massive fine particles in a giant deposition system becomes possible.

The invention relates to a shale full pore size distribution and connectivity quantitative characterization method. The method comprises the following steps: respectively determining a two-dimensional nuclear magnetic resonance T1-T2 spectrum and a nuclear magnetic resonance T2 spectrum of a dry sample core and a saturated oil core, carrying out a high-pressure mercury injection test on a parallel sample of the core, completing benchmarking of T2 and pore throat radius, and determining core communication aperture distribution; (2) splitting the rock core into sheets along the lamella, determining a two-dimensional nuclear magnetic resonance T1-T2 spectrum of the sheet-shaped dry sample rock core, comparing the two-dimensional nuclear magnetic resonance T1-T2 spectrum with the T1-T2 spectrum of the dry sample rock core, and calculating the distribution of the disconnected seams of the rock core; (3) grinding the rock core into 200-mesh particles, measuring the two-dimensional nuclear magnetic resonance T1-T2 spectrum of the granular dry sample rock core, comparing the two-dimensional nuclear magnetic resonance T1-T2 spectrum with the T1-T2 spectrum of the sheet-shaped dry sample rock core, and calculating the distribution of disconnected holes of the rock core; and (4) calculating shale full pore size distribution and connectivity. According to the method, nuclear magnetic resonance testing is carried out on shale in different states and forms, and quantitative characterization of shale full pore size distribution and connectivity of different storage spaces is achieved.

The invention discloses a method for purifying high-purity quartz sand, which belongs to the technical field of preparation of high-purity quartz sand, and comprises the following steps: (1) sequentially carrying out high-pressure water jet scrubbing, gradient screening classification and dielectric separation on sandstone type quartz ore raw ore with SiO2 content of 85-90% to remove feldspar to obtain quartz particles with feldspar content of less than or equal to 2%; (2) sequentially carrying out microwave field pretreatment, infrared light field crack propagation and pulse laser implosion stripping on the quartz particles obtained in the step (1), and regulating and controlling technological parameters of the three fields through linkage of a PLC (Programmable Logic Controller) system, so that the stripping rate of an impurity inclusion is greater than or equal to 92%; according to the invention, aiming at quartz particles with different particle sizes, a plurality of process parameters are automatically optimized and adjusted through the PLC system, accurate control and adaptive production are realized, and high-purity products can be stably produced from sandstone type quartz raw materials with different grades in different regions. And the inclusion is opened from inside to outside through a multi-field synergistic effect, and the completeness of the quartz particles is retained to the greatest extent by combining with an optimized fluoride-free acid leaching condition.

The invention relates to the technical field of marine deposition backflow sand recovery, and discloses a marine deposition backflow sand recovery method which comprises the following steps: (1) backflow tail mud collection and concentration regulation and control: systematically collecting overflow tail mud from a mortar ore storage hopper and a hydraulic classifier in a marine deposition sand beneficiation process, pumping the backflow tail mud into a slurry mixing tank, and carrying out slurry mixing and concentration regulation and control on the overflow tail mud; the mass concentration is accurately regulated and controlled within the range of 32%-48%; the backflow tail mud generated in the marine sedimentary sand beneficiation process is collected through the system, a multi-step cooperative treatment technology is adopted, especially ultrasonic cavitation and mechanical cooperative dispersion, enhanced secondary scrubbing, precise hydraulic cyclone classification and other technical means are adopted, particle aggregates formed by wrapping of salt and fine mud are effectively dissociated, and the separation effect is good. Therefore, qualified quartz sand particles of + 0.15 mm which are lost in the tail mud originally are efficiently recovered, the overall recovery rate of the quartz sand is remarkably improved, waste of precious silicon resources is reduced, and the comprehensive utilization level of the resources is improved.

The invention discloses a water-rich broken surrounding rock directional grouting method based on an external magnetic field. The method comprises the following steps that 1, geological exploration is conducted on a target water-rich broken surrounding rock area; step 2, mixing the base material, the nano ferroferric oxide magnetic particles, the rheology regulating agent, the dispersing agent and the coagulation accelerator according to a mass ratio; 3, injecting alternating current with the frequency of 50-500Hz into the electromagnetic coil to generate a rotating magnetic field with the intensity of 3-10kA / m, and driving the slurry to directionally migrate along the main fracture area; 4, the grouting pressure of the pre-buried pressure sensor is monitored in real time, when the pressure change rate delta P / delta t is larger than or equal to 0.1 MPa / min, the electromagnetic coil injection frequency is switched to alternating current of 1 kHz to 10 kHz, so that the intensity of a magnetic field is improved to 8 kA / m to 15 kA / m, and grouting on the micro-crack area is enhanced; and 5, when the pressure change rate delta P / delta t is smaller than + / -0.1 MPa / min and lasts for 5-10 min, grouting operation is ended. The method aims at solving the problems that in grouting reinforcement of the water-rich fractured stratum, slurry is lost along with water flow, micro-cracks are difficult to fill, and reinforcement bodies are distributed unevenly.

The invention relates to a karst area rock sample penetration damage simulation method and system based on discrete elements, and belongs to the field of geotechnical engineering. The invention discloses a karst area rock sample penetration damage simulation method based on discrete elements. The karst area rock sample penetration damage simulation method comprises the following steps: S1, constructing a fracture damage constitutive model reflecting a karst area rock discontinuous surface position; s2, inputting parameters and conditions based on a discrete element method and the fracture damage constitutive model reflecting the position of the rock discontinuous surface in the karst area, and calculating particle stress information; s3, calculating the particle speed and displacement according to the particle stress information to obtain a calculation result; s4, outputting the calculation result; wherein in the step S2, according to the position relation between the particles and the discontinuous surface, the damage coefficient of the discontinuous surface is introduced, the particle stress information is dynamically corrected, and the penetration mechanical response under different discontinuous surface positions is accurately simulated. According to the method, the position and the crushing damage degree of the discontinuous surface of the rock are considered, a new rock sample model is constructed, and more accurate simulation is realized.

The invention relates to a rock mass splitting test device and method based on granular slurry perfusion, the device comprises a loading mechanism and a grouting mechanism, the loading mechanism comprises an inner cavity, an outer cavity and a loading unit, a rock mass sample is arranged in the inner cavity, the loading unit is connected with the rock mass sample and the outer cavity, and the outer cavity is connected with the loading unit; wherein the loading unit comprises multiple stages of loading assemblies which are perpendicular to the surface of the rock mass sample and are arranged in a layered mode, slurry guide holes are formed in the rock mass sample, the loading unit is provided with a grouting pipeline, a grouting device of the grouting mechanism is provided with a driving assembly connected with a pump body and a slurry cavity connected with the grouting pipeline, and the grouting device is rotationally connected with the frame bodies on the two sides. According to the technical scheme, the multi-stage loading assemblies are arranged from the center of the rock mass sample to the edge layer by layer, and the number of the assemblies providing loads can be freely combined, so that the stress area acting on the surface of the rock mass sample is flexibly changed, stress areas in different shape ranges are formed, cracks in different forms are further induced to be generated, and diversified test requirements are met.

The invention provides a semi-analytical MPM-DEM coupling numerical simulation method for interaction of debris flow and a structure, and relates to the field of geotechnical engineering disaster simulation. Taking the fine-grain slurry as a continuous medium, and discretizing by adopting MPM; meanwhile, spherical particles and clustered particles serve as solid phases, and DEM modeling is adopted; structures and boundaries are embedded into the computational domain in the form of rigid walls. Through grid-particle information exchange and two-way transmission of particle-grid coupling force, synchronous solution of fluid-solid multiphase coupling is realized. The fluid-solid contact force adopts a semi-analysis mode; the DEM particles and the DEM particle-wall contact are accurately calculated on the basis of a Hertz-Mindlin model, and the DEM particle-wall contact is accurately calculated on the basis of a Hertz-Mindlin model. According to the method, collaborative collision, blockage and impact mechanisms of block stones and floating woods in debris flow are truly represented, and the three-dimensional large-scale situation of million-level fluid mass points and million-level particles is simulated. The simulation result can output key indexes such as the stress time history, the impact peak value and the blockage rate of the structure, and a reliable numerical basis is provided for debris flow protection.

The invention discloses a method for accurately measuring the content of elements in fine mineral powder, and relates to the technical field of fine mineral powder separation and determination, and the method comprises the following steps: S1, Thai sieve classification and production control final analysis; s2, ultrasonic sedimentation and micro powder pre-domestication; s3, carrying out double-sample separate test and conditional detection; s4, carrying out dense time measurement and particle fraction separation; and S5, precipitating a combined wall-particle size assembly. According to the method, the minerals exist in a more appropriate particle state by optimizing field operation, and the grading effect is enhanced, so that the recovery effect of useful minerals is improved, the loss in tailings is reduced, and the problem of determining the content of particles with different sizes and the content of elements in the separation and detection of the micro-fine-particle-grade minerals is solved.

A method for building a 3D model of a reservoir includes defining a pre-sedimentation model comprising a bottom surface comprising a plurality of cells, and iterating a plurality of deposition modelling steps, including simulating deposition of a layer of sediments on the bottom surface or a previously-deposited layer of sediment, each layer corresponding to a determined period of time of sedimentation and comprising a plurality of cells, and computing petrophysical parameters associated to at least a cell of the generated layer. Simulating deposition of a layer of sediments includes introducing a plurality of particles within the model, simulating transport of the particles comprising moving a particle from one cell to another or depositing the particle, and generating a layer comprising a plurality of cells, each cell associated to a thickness of deposited particles. The petrophysical parameters are computed from mineral elements and sizes of the particles deposited in each cell.

The objective of the present invention is to provide a method for producing a core-shell particle without requiring the synthesis of a core particle and the adjustment of the electric charge of the surface of the core particle, and to provide a method for producing a hollow particle without requiring thermal energy in a hollowing step of the core-shell particles. The method for producing the core-shell particle according to the present invention includes a step for forming a shell by directly fluorinating the surface layer of a core particle consisting of a magnesium inorganic salt. Next, the method for producing a hollow particle of a fluoride includes a step for removing only the core particle with an acid from the core-shell particle obtained by the above-mentioned producing method.

The application discloses a method for identifying the dispersion mode of oil and gas through a cap layer, and relates to the technical field of oil and gas reservoirs. The technical scheme is as follows: selecting a rock sample, carrying out particle fluorescence testing, and obtaining a parameter QGF-E representing the content of hydrocarbon adsorbed on the outside of a mineral particle and a parameter QGF-index representing the content of hydrocarbon in the inside of the mineral particle; identifying the dispersion mode of oil and gas through the cap layer according to the relationship between QGF-E and QGF-index, wherein if QGF-E is positively correlated with QGF-index, it indicates that the dispersion mode of oil and gas through the cap layer is slow percolation; and if QGF-index basically remains unchanged with the increase of QGF-E, it indicates that the dispersion mode of oil and gas through the cap layer is episodic rupture. The analysis and testing data obtained through the quantitative fluorescence testing of the cap layer are used to distinguish the dispersion mode of oil and gas through the cap layer by using the quantitative fluorescence data of the cap layer, so that the dispersion mode of oil and gas through the cap layer can be accurately identified, and the problems of randomness and multiple solutions in the prior art can be effectively avoided.

This invention relates to a method for characterizing the distribution of primordial water in rocks and its application. The method includes: preparing particles from fresh rock cores as fresh samples and particles from dried rock cores as dried samples; calculating the scattering length density of the rock to be tested based on the dried sample, and preparing a deuterated toluene contrast-matching fluid with the same scattering length density as the rock to be tested; immersing the fresh sample and the dried sample in the deuterated toluene contrast-matching fluid respectively to obtain immersion samples; performing small-angle neutron scattering (SANS) experiments on the dried sample and the immersion samples respectively; obtaining pore structure information before and after immersion based on the experimental results; and determining the distribution of primordial water in the rock to be tested based on the pore structure information. This invention, based on SANS experiments, provides a novel experimental technique for characterizing the distribution and water saturation of primordial water in sedimentary rocks, with advantages such as being non-destructive, efficient, time-saving, and highly accurate.

The archaeological excavation auxiliary equipment comprises a support, a shell, a first driving part, a flexible crushing assembly and a grading assembly. The stirring blades provide mild water flow shearing force and extrusion force to assist in separation of loosened soil particles, the shell swinging in a reciprocating mode can make remain particles precipitated in the soaking cavity flow and gather, and the extrusion and dispersion effect of the stirring blades on the soil particles during descending is improved; the screening groove inclines in a reciprocating mode under the reciprocating swing effect of the shell, so that soil particles and remain particles roll back and forth on the screening groove, the soil particles are further dispersed under the scouring effect of flushing water, all positions of the remain particles are scoured, and the follow-up block pushes the soil particles and the remain particles to roll in the screening groove. Friction and rubbing effects are formed between the remain particles and the bottom wall of the screening groove, the remain particles are fully separated from the soil, and the separation effect is good.

The invention discloses a cyclone separation unit, which is used for deoiling treatment of rock debris particles of more than 100 microns in oil-based mud, and at least comprises a plurality of material distribution cavities and barrel bodies which are arranged at intervals along the vertical direction; an oil-based mud material inlet and a gas inlet are formed in the top of the uppermost material distribution cavity and are used for receiving rock debris particles which are subjected to vibration screening and heating viscosity reduction treatment and contain the particle size of 100 microns or above and rotational flow driving gas; the multiple hydrocyclones are arranged in a multi-stage series-parallel connection mode; a multi-stage cyclone bin and a double-ring channel are arranged in each cyclone, and airflow carrying rock debris particles sequentially flows downwards in an outer ring of the double-ring channel, flows upwards in an inner ring of the double-ring channel and enters the multi-stage cyclone bin from top to bottom; in the cyclone bin, under the action of cyclone, airflow carries an oil phase removed from the rock debris particles to move upwards and flow out from an overflow port, and the rock debris particles move downwards under the action of gravity and are discharged from an underflow port. The invention further discloses an oil-based mud treatment device and method applying the cyclone separation unit.

The application discloses a TBM support grade decision-making method and system based on images and deep learning, and belongs to the technical field of TBM intelligent monitoring. Taking the type and structure parameters of a surrounding rock support structure as indexes, a surrounding rock support grade decision-making scheme is generated based on a screened historical picture data set; a rock slag discharge picture segmentation model is established, a trained rock slag discharge picture segmentation model is used to perform segmentation processing on newly collected TBM rock slag discharge pictures to output a rock slag segmentation prediction graph; a multi-dimensional rock slag parameter calculation system is constructed to determine a large block area in the rock slag segmentation prediction graph; the degree of surrounding rock crushing is judged based on the rock slag particle parameters of the large block area; and a matched support decision-making scheme is matched in combination with the surrounding rock support grade decision-making scheme. The application converts experience judgment into data-driven quantitative decision-making by collecting rock slag discharge pictures to construct a data set, correlating rock slag image features with geological parameters, and generating a support grade decision-making scheme in combination with clustering analysis and a quantitative model.

The present application relates to the geological exploration technical field, more particularly, to a deep water super shallow layer natural gas reservoir rock physics shear wave velocity prediction method, comprising: calculating equivalent bulk modulus, shear modulus and density of a plurality of mineral mixed matrix according to shale content; then calculating skeleton bulk modulus and shear modulus; then calculating saturated rock bulk modulus and shear modulus through a model, and calculating saturated rock density through rock matrix density; distributing longitudinal and transverse velocities of suspended state and bearing state, and calculating equivalent longitudinal and transverse wave velocities; using equivalent longitudinal wave velocity to construct an inversion objective function with longitudinal wave velocity as a known condition; comparing actual longitudinal wave velocity with calculated longitudinal wave velocity; realizing nonlinear inversion of transverse wave velocity according to an algorithm, and obtaining transverse wave velocity of a to-be-inverted work area. The present application simultaneously considers rock physics models of particle suspended state and bearing state, and realizes transverse wave velocity prediction and deep water super shallow layer natural gas reservoir transverse wave velocity direct inversion.

The application discloses a multi-stage gradient anti-silt underwater equipment, which comprises a static part and a rotating part rotating relative to each other. Outside the core support gap, a flow guiding and sand throwing part and an expansion and sedimentation part are arranged in sequence from upstream to downstream along the water flow direction. The flow guiding and sand throwing part is an annular step arranged on the static part, which utilizes water flow inertia separation to throw large particle silt out of the side; the expansion and sedimentation part is an annular groove arranged on the inner hole wall of the static part, which utilizes the low-speed vortex area formed by the sudden change of the flow passage section to make fine sand particles settle and be intercepted in the groove; the two parts are cooperated with each other, and the different particle size silt is classified and intercepted through inertia separation and vortex settlement respectively. An end face flow guiding part can also be arranged, which generates centrifugal force relying on the mechanical movement of the rotating part to dredge fine particles. The application has simple structure, no vulnerable parts, and is suitable for silt-containing underwater working conditions, and can prolong the service life of the equipment.

The application provides a method for measuring and calculating the grade of silver minerals above 0.037 mm, and belongs to the technical field of mineral grade detection. The application measures and calculates the silver grade in the sample through screening; measures and calculates the content of silver monomer and silver minerals by leaching, and obtains heavy sand products by gravity separation; the heavy sand products are dyed by fluorescence, and monomer silver minerals are selected; the color of the silver minerals is analyzed by scanning electron microscope point scanning data, and the volume of the monomer silver minerals is obtained by melting, so that the content is calculated; the grade of silver minerals above 0.037 mm is obtained by conversion. The application adopts density medium gravity separation and fluorescent dye tracing to quickly and accurately obtain the target minerals; the actual density of the silver minerals is measured and calculated by introducing a scanning electron microscope instead of the theoretical density, the silver minerals are smelted in a mold, the volume is measured and calculated, and the real metal amount of the silver minerals is obtained, which is closer to the actual value; the calculation error caused by impurities and irregular shape of the mineral particles is reduced; and the calculated grade of the silver minerals is more accurate.

The invention discloses an argillaceous sandstone uranium ore particle size gradient grading method based on online particle size detection. The method comprises the following steps: ore crushing; first-stage rotational flow classification is carried out, and the classification cutting particle size is N1; scrubbing and stripping; second-stage rotational flow classification is carried out, and the classification cutting particle size is N2; on-line sampling and particle size detection are carried out at an overflow port of the first-stage swirling flow field and an overflow port of the second-stage swirling flow field, when particles larger than N2 are lower than M1, materials are conveyed to a fine ore pulp storage pool, otherwise, the materials return to a primary pulp pool or are scrubbed and stripped, and the pulp inlet pressure of a slurry pump is adjusted; on-line sampling and particle size detection are carried out at an underflow port of a second-stage swirling flow field, when particles smaller than N2 are smaller than M2, high-frequency linear dehydration is carried out after the materials are output, otherwise, scrubbing and stripping are carried out, and the slurry inlet pressure of a second-stage slurry pump and the size of the underflow port of the second-stage swirling flow field are adjusted. The online particle size detection in the mud sand gradient separation and grading process of the argillaceous sandstone uranium ore can be realized, a positive and negative feedback intelligent regulation and control system is coupled, input parameters in the technological process are intelligently optimized, and the grading and separation precision and quality are ensured.

The invention discloses a method for rapidly and accurately determining multiple elements of limestone powder based on a fuse piece method, and belongs to the technical field of material detection. A fuse piece scheme is designed aiming at the characteristics of fine particles, easy moisture absorption and the like of limestone powder instead of improving a general scheme of materials such as limestone, dolomite and the like, key parameters are optimized, the flux ratio is set as follows: the ratio of lithium tetraborate to lithium metaborate is 67: 33, melting is divided into three processes of preheating, pre-oxidation and melting, the melting temperature is effectively controlled to be 1060 DEG C, the time is 60 seconds, and the melting efficiency is greatly improved. The problem that limestone powder is prone to excessive melting or uneven melting is solved, the matrix effect and the particle size effect are greatly reduced, it is verified that three limestone powder standard samples with known components are selected for testing, the relative error between the result and the standard value is smaller than 1%, data meet the strict allowance requirement of the industry, and compared with an existing fuse piece method, the method has the advantage that the cost is low. The detection adaptability to the limestone powder is remarkably improved, and the component detection requirements of mainstream limestone powder in the industry can be met.

This invention belongs to the field of low-carbon technology in metallurgical pelleting, and particularly relates to a precise batching method for producing high-basicity pellets using a chain-loop process. The steps are as follows: Step 1: Concentrate pre-batching: Pre-batching is added during the concentrate batching stage. The content of TFe and SiO2 in the iron concentrate is analyzed, and the concentrate is temporarily stored in batches in storage silos according to the content, forming a component-stable iron concentrate powder. Step 2: Limestone powder batching: The amount of limestone powder to be added is automatically calculated based on the SiO2 content of the concentrate powder after pre-batching, the set basicity of the pellets, and the amount of bentonite added, and then automatically added. Step 3: Roll milling: A roller milling step is added after the iron concentrate powder and limestone powder are mixed. Step 4: Bentonite addition: An appropriate amount of bentonite is set according to the quality of the green pellets. This method forms a component-stable iron concentrate powder by setting precise pre-batching, and combined with the high-pressure roller milling process after mixing the iron concentrate powder and limestone powder, the surface is not easy to peel off, thus improving the pelletizing rate.

The application provides a honeycomb reef limestone numerical model coupling generation method, comprising the following steps: S1, the structural characteristics of a honeycomb reef limestone sample are characterized as a plurality of n-polygon unit bodies, and geometric parameters of the unit bodies are determined; S2, a pore radius is determined; S3, a three-dimensional geometric model of the unit bodies is established by using finite element software; S4, the three-dimensional geometric model of the unit bodies is subjected to particle filling by using discrete element software; S5, the unit bodies are copied, arranged and combined to form a three-dimensional geometric model of a complete sample; S6, a radial pore structure is generated in the three-dimensional geometric model of the complete sample by using pore particles, and the radius of the pore particles is equal to the pore radius in step S2; and S7, the pore structure is deleted, and contact properties are applied to the particles of the three-dimensional geometric model of the complete sample. The application can perform three-dimensional fine modeling on the skeleton structure of the honeycomb reef limestone, and provide an accurate model for the study of the meso-mechanical characteristics of the reef limestone and the simulation calculation of the bearing capacity of an actual engineering foundation.

This invention discloses a method and system for determining the fracture evolution process of hard rock containing microfractures, belonging to the field of rock mechanics testing technology. By determining the DIC (Digital Disc Reflection) test observation surface of the hard rock sample, digital speckle images of the DIC test observation surface of the hard rock sample are acquired in real time during the loading process of indoor mechanical tests. By determining the surface displacement field of the hard rock sample, displacement vector diagrams of fine-grained points in the digital speckle image are obtained to determine the type of newly formed cracks. Multiple displacement observation points are marked on both sides of the primary microfractures. By judging whether the tangential and normal displacements of the displacement observation points are separated, the fracture type of multiple displacement observation points is determined. Based on the type of newly formed cracks and the fracture type of the displacement observation points, the dynamic evolution process of the primary microfractures under stress conditions is determined. This method can accurately characterize the dynamic evolution process of cracks from initiation to propagation, thereby revealing the intrinsic relationship between the spatial geometric characteristics of crack distribution and the hard rock fracture evolution mechanism.

A method for simulating dissolution within a reservoir over a determined time period includes receiving a graph model of the reservoir comprising nodes and connections between the nodes, wherein each node is associated with at least one geological parameter, and simulating dissolution induced by a plurality of particles flowing through the reservoir during the time period. Each particle corresponds to both a volume of fluid and a volume of rock that the particle is able to dissolve. Simulating dissolution comprises, for each particle: determining a path of the particle through the graph model, determining a volume of rock dissolved by the particle at each node belonging to the path of the particle from the total volume of rock dissolved by the particle within the reservoir, and modifying the geological parameters associated with the nodes of the path according to the dissolved volume of rock at each node.

This invention discloses a method for increasing shale gas production from multi-stage fracturing shale formations. First, water containing water-absorbing resin is intermittently injected into the shale gas well, impacting the shale layer and creating multiple fractures, forming a primary fracturing process. Next, liquid nitrogen and sodium particles are injected into the shale gas well. The resin, already saturated with water, remains within the fractures. At this point, the liquid nitrogen cools the shale layer below its freezing point, causing the saturated resin to freeze and rapidly expand, forming a secondary fracturing process. Then, as the injected liquid nitrogen continues to vaporize, it further freezes the water and water-absorbing resin adsorbed by the shale, forming a tertiary fracturing process. When the temperature of the shale layer exceeds its freezing point, the expanded ice on the water-absorbing resin melts into water. At this point, the sodium particles react with the water, releasing a large amount of heat, causing the shale layer temperature to rise rapidly, creating a thermal shock to the low-temperature shale layer, forming a quaternary fracturing process. This completes the multi-stage fracturing process of the shale layer, effectively improving the extraction efficiency of shale gas.

The invention provides a modeling method and a saturation prediction method of a rock physical model containing non-uniformly distributed hydrate sediments. Comprising the steps of obtaining model parameters, calculating the porosity of a mineral skeleton based on the model parameters, calculating the bulk modulus and the shear modulus of a dry hydrate skeleton, calculating the bulk modulus and the shear modulus of a dry mineral skeleton, and calculating the bulk modulus and the shear modulus of a dry composite skeleton composed of the dry mineral skeleton and the dry hydrate skeleton. And calculating the rock bulk modulus and shear modulus when the fluid is saturated, calculating the rock density value when the fluid is saturated, and calculating the stratum longitudinal wave velocity and the stratum transverse wave velocity. According to the method, on the basis of the forming mechanism and distribution characteristics of the non-uniformly distributed hydrates, the non-uniformity of the hydrates and mineral particles is considered in the modeling process, the hydrates and the mineral particles are regarded as two independent rock frameworks, and the isotropic rock physical model suitable for the non-uniformly distributed hydrates is constructed.

The invention discloses a method and system for determining the fracture evolution process of hard rock containing microfractures, and belongs to the technical field of rock mechanical testing. Digital speckle images of a DIC test observation surface of a hard rock sample in the loading process of an indoor mechanical test are collected in real time by determining the DIC test observation surface of the hard rock sample; by determining a surface displacement field of the hard rock sample, a displacement vector diagram of microscopic particle points of the digital speckle image is obtained, and the type of new cracks is judged; a plurality of displacement observation points are calibrated on the two sides of the native microfracture, and the fracture types of the displacement observation points are determined by judging whether tangential displacement and normal displacement of the displacement observation points are separated or not; and according to the type of the new crack and the fracture type of the displacement observation point, determining the dynamic evolution process of the native micro-crack under the stress condition. According to the method, the dynamic evolution process of cracks from initiation to expansion can be accurately represented, and then the internal correlation between the spatial geometric characteristics of crack distribution and the hard rock fracture evolution mechanism is disclosed.

The invention provides an ancient coastal sand dam prediction method and device, equipment and a medium, and relates to the technical field of oil-gas exploration. Comprising the following steps: acquiring fluctuation data of an ancient landform in a region, wave mark parameters in sedimentary rock, sediment particle diameter and sediment density; according to the fluctuation data of the ancient landform, determining the gradient of the ancient landform of the region; determining the sedimentary paleo-water depth according to the wave mark parameter, the sediment particle diameter and the sediment density in the sedimentary rock; and the thickness of the ancient coastal sand dam is determined according to the paleo-terrain gradient and the sedimentary paleo-water depth. According to the method, the thickness of the paleo-coastal sand dam is determined by analyzing the paleo-terrain gradient and the sedimentary paleo-water depth in the area, the potential reservoir in the area is rapidly identified in the early stage of exploration, and a basis is provided for well drilling deployment.