Prediction method for homogeneity of all tailings-waste gypsum body in long and narrow stope

Abstract

The invention discloses a method for predicting the homogeneity of a whole tailing-waste gypsum body in a long and narrow stope, belongs to the technical field of mine filling, and solves the problem that the homogeneity evaluation of a filling body depends on experience speculation due to the fact that dynamic sedimentation and aggregation behaviors of waste rocks are difficult to directly observe at the present stage. The method comprises the following steps: carrying out basic physical experiment measurement on a filling material, and measuring a waste rock settlement result of the whole tailings-waste gypsum body in a long and narrow drift under the influence of different factors based on similar experiments, numerical simulation is adopted to analyze the spatial distribution state of the full tailings-waste gypsum bodies in the long and narrow stope and the influence of the positions and the number of feed openings on the homogeneity of the slurry; on the basis of similar experiments and dynamic parameter analysis, a homogeneity prediction model considering the coupling effect of multiple factors such as the filling flow, the waste rock particle size, the particle size grading and the position of a discharging opening is established. The homogeneity of the filling body is quantitatively evaluated through the uniformity coefficient, and the uniformity change trend of waste rock distribution in the slurry flowing process under different working conditions can be predicted.

Description

Technical Field

[0001] The invention belongs to the technical field of mine filling, and in particular relates to a method for predicting the homogeneity of a full tailings-waste gypsum body in a narrow and long stope. Background Art

[0002] With the continuous growth of global demand for mineral resources and the gradual depletion of shallow resources, deep ore mining has become an inevitable direction of mining development. However, deep mining faces the challenges of high stress, high ground temperature and complex geological conditions, which place higher demands on the stability, homogeneity and safety of the filling body. Among traditional filling technologies, full tailings-waste gypsum is widely used for filling underground goafs due to its environmental, economic and mechanical properties. Among them, waste rock is added to the slurry as coarse aggregate, which can effectively improve the permeability, fluidity and compressive strength of the filling body, while reducing the amount of cementitious materials and saving costs. However, the density of waste rock is significantly higher than that of the slurry matrix. It is prone to settlement and stratification during long-distance transportation and narrow access filling. This leads to a decrease in the waste rock content and uneven structure of the distal filling body, which in turn causes problems such as insufficient filling strength, settlement deformation and even cracking, seriously affecting mining safety and resource recovery efficiency.

[0003] On the other hand, the approach mining technology occupies an important position in the mining of complex ore bodies due to its characteristics of flexible control of mining range and reduction of dilution losses. However, with the increase of the approach length, the flow characteristics of the whole tailings-waste gypsum in the narrow and long mining area tend to be complex. The slurry flow resistance and the waste rock settling effect work together to easily form an "uneven flow" phenomenon, which is manifested as uneven distribution of aggregates on the surface and bottom of the slurry and severe local segregation. Current research focuses on the optimization of the proportion of whole tailings or graded tailings and the characterization of static filling strength, while the research on the homogeneity evolution mechanism of waste rock-whole tailings paste slurry during dynamic flow is seriously insufficient. Existing results are mostly based on slurry performance tests under static or semi-static conditions, and lack theoretical models and technical means for the real-time prediction of waste rock migration laws, slurry stratification dynamics and homogeneity under flow conditions. Especially in actual engineering, the flow process of slurry after entering the mine is regarded as a "black box", and the dynamic settlement and aggregation behavior of waste rock are difficult to observe directly, resulting in the evaluation of filling homogeneity relying on empirical speculation, which cannot meet the needs of precise control in deep and complex mining scenarios. To address the above problems, we proposed a method for predicting the homogeneity of full tailings-waste gypsum in narrow and long mines. Summary of the Invention

[0004] The purpose of the present invention is to address the shortcomings of the existing technology and provide a method for predicting the homogeneity of full tailings-waste gypsum in narrow and long mining areas. It solves the problem that the flow process of the slurry after entering the mining area is currently regarded as a "black box", and the dynamic settlement and aggregation behavior of the waste rock are difficult to directly observe, resulting in the evaluation of the homogeneity of the filling body relying on empirical speculation, which cannot meet the needs of precise control in deep and complex mining scenarios.

[0005] At present, the flow process of slurry after entering the stope is regarded as a "black box", and the dynamic settlement and aggregation behavior of waste rock are difficult to observe directly, resulting in the evaluation of filling homogeneity relying on empirical speculation, which cannot meet the needs of precise control in deep complex mining scenarios. To address the above problems, we proposed a method for predicting the homogeneity of full tailings-waste gypsum in narrow and long stopes. When implementing the method, basic physical experimental measurements are first performed on the filling materials. Then, based on similar experimental measurements, the waste rock settlement results of full tailings-waste gypsum in narrow and long access roads under the influence of different factors are measured. According to the settlement results, a slurry homogeneity prediction model is obtained. Finally, numerical simulation is used to analyze the spatial distribution state of full tailings-waste gypsum in narrow and long stopes, as well as the influence of the position and number of the feed port on the slurry homogeneity. Based on the numerical simulation analysis results and the slurry homogeneity prediction model, the optimal filling parameters and feed port position are determined. In this embodiment of the present invention, the physical properties and particle size distribution of waste rock particles are determined through basic physics experiments. Combined with similar simulation experiments, dynamic observations of waste rock settling behavior in narrow and long feedways are conducted. This clarifies the stratified migration mechanism of waste rock during flow. Based on similar experiments and dynamic parameter analysis, a homogeneity prediction model is established that considers the coupling effects of multiple factors, including filling flow rate, waste rock particle size, particle size grading, and feed port location. By quantitatively evaluating the homogeneity of the filling mass using the uniformity coefficient, the uniformity trend of waste rock distribution during slurry flow under different operating conditions can be predicted. This overcomes the limitations of existing technologies, which rely on static experimental data and cannot adapt to complex dynamic conditions.

[0006] The present invention is achieved by providing a method for predicting the homogeneity of a whole tailings-waste gypsum body in a narrow and long stope, the method comprising:

[0007] S10, obtaining filling materials, performing basic physical experimental measurements on the filling materials, and obtaining basic physical parameters of the filling materials;

[0008] S20, loading the basic physical parameters of the filling material, based on similar experimental measurements of the waste rock settlement results of the full tailings-waste gypsum in a narrow and long passage under the influence of different factors, and deriving a slurry homogeneity prediction model based on the settlement results;

[0009] S30, load the slurry homogeneity prediction model, use numerical simulation to analyze the spatial distribution of the whole tailings and waste gypsum in the narrow and long stope, and the influence of the location and number of the feed port on the slurry homogeneity. Based on the numerical simulation analysis results and the slurry homogeneity prediction model, the optimal filling parameters and feed port location are determined.

[0010] Preferably, the method of performing basic physical experimental measurements on the filling material comprises:

[0011] S101, conduct physical and chemical property tests on filling materials, including water content, specific gravity, loose / tight bulk density, porosity, and particle size distribution;

[0012] S102, using the bucket method to test the angle of accumulation of waste rock particles in the filling material;

[0013] S103, designing orthogonal experiments based on the static friction coefficient between waste rock particles, the dynamic friction coefficient between waste rock particles, and the range of the recovery coefficient of waste rock particles, and simulating the waste rock accumulation angle under different contact parameters using discrete element software;

[0014] S104, using Design expert software to fit the experimental parameters, obtain the relationship between the three factors and the stacking angle, and bring the measured waste rock stacking angle into the equation to obtain the optimal waste rock particle-waste rock particle static friction coefficient, waste rock particle-waste rock particle dynamic friction coefficient, and waste rock particle recovery coefficient.

[0015] Preferably, the method for obtaining a slurry homogeneity prediction model based on the sedimentation results comprises:

[0016] S201, select experimental factors and design experiments based on mine requirements;

[0017] S202: Establish a similarity model based on the actual mine stope conditions, calculate an experimental filling flow rate based on the actual mine filling flow rate, and conduct a similar simulation experiment. Inject the mixed slurry into a filling funnel through a pipe so that the slurry flows into the simulated stope. The slurry flows in the simulated stope under the action of its own gravity and initial dynamic force until it is filled to the designated position.

[0018] S203, using a 1 mm pore size sieve to screen out waste rock with a particle size larger than 1 mm, and then transferring the waste rock to an oven for drying. After drying, using a 5 mm pore size sieve to separate the waste rock into particles between 1 mm and 5 mm and particles larger than 5 mm;

[0019] S204, calculating the mass fraction of waste rock particles at different locations using a formula, and analyzing the deposition of large-size waste rock and small-size waste rock at different locations in the simulated stope and the deposition of waste rock in the stope under different conditions;

[0020] S205, after conducting multiple experiments, obtain the uniformity coefficient of the whole tailings-waste gypsum body in the narrow and long stope under different factors, and construct a homogeneity prediction model of the whole tailings-waste gypsum body in the narrow and long stope based on the experimental results.

[0021] Preferably, a numerical simulation method is used to analyze the spatial distribution of the whole tailings-waste gypsum in the narrow and long stope and the influence of the position and number of the feed openings on the slurry homogeneity, including:

[0022] S301, constructing a numerical model that is consistent with the actual mine conditions and performing grid division on the numerical model;

[0023] S302, treating the full tailings slurry as a continuous phase and the waste rock as a discrete phase, setting fluid parameters and boundary conditions in computational fluid dynamics software, and setting waste rock parameters in discrete element software;

[0024] S303, coupling setting is performed on the continuous phase and the discrete phase, and the control equation for the interaction between the fluid phase and the discrete phase is set according to actual needs.

[0025] S304: After the simulation is completed, the distribution of waste rock particles in the stope space and the influence of the feed opening position on the homogeneity of the whole tailings-waste rock mass are analyzed using discrete element software;

[0026] S305, determining the spatial distribution of waste rock particles and the location of the discharge port according to the numerical simulation results, and determining the optimal filling parameters and the location of the discharge port based on the numerical simulation analysis results and the slurry homogeneity prediction model.

[0027] Compared with the prior art, the embodiments of the present application have the following beneficial effects:

[0028] In this embodiment of the present invention, the physical properties and particle size distribution of waste rock particles are determined through basic physics experiments. Combined with similar simulation experiments, dynamic observations of waste rock settling behavior in narrow and long feedways are conducted. This clarifies the stratified migration mechanism of waste rock during flow. Based on similar experiments and dynamic parameter analysis, a homogeneity prediction model is established that considers the coupling effects of multiple factors, including filling flow rate, waste rock particle size, particle size grading, and feed port location. By quantitatively evaluating the homogeneity of the filling mass using the uniformity coefficient, the uniformity trend of waste rock distribution during slurry flow under different operating conditions can be predicted. This overcomes the limitations of existing technologies, which rely on static experimental data and cannot adapt to complex dynamic conditions.

[0029] The present invention proposes a method for predicting the homogeneity of full tailings-waste gypsum in a narrow and long stope. By combining physical experiments with numerical simulations, a stope model that conforms to the actual mine situation is constructed. By studying the influence of different factors on the uniformity of the slurry, a homogeneity prediction model for full tailings-waste gypsum in a narrow and long stope is established. Numerical simulation is then used to analyze the influence of the spatial distribution state and the position of the discharge point on the homogeneity, so as to achieve the homogeneity prediction of full tailings-waste gypsum in a narrow and long stope and the determination of the optimal filling parameters. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 The figure shows the particle size distribution of the whole tailings and waste rock obtained in Example 1 of the present invention.

[0031] Figure 2 A similar simulation experimental device diagram obtained in Example 2 of the present invention is shown.

[0032] Figure 3 The diagram shows the locations of sampling points in Example 2 of the present invention.

[0033] Figure 4 The figure shows the distribution diagram of 1mm-5mm waste rock obtained in Example 2 of the present invention.

[0034] Figure 5 The distribution diagram of waste rock with a diameter of >5 mm obtained in Example 2 of the present invention is shown.

[0035] Figure 6 The figure shows the distribution diagram of waste rock with all particle sizes obtained in Example 2 of the present invention.

[0036] Figure 7 The figure shows the numerical model diagram of the stope obtained in Example 3 of the present invention.

[0037] Figure 8 The particle distribution diagram along the horizontal direction obtained in Example 3 of the present invention is shown.

[0038] Figure 9 The particle distribution diagram along the vertical direction obtained in Example 3 of the present invention is shown. DETAILED DESCRIPTION

[0039] Unless otherwise defined, all technical and scientific terms used herein have the same meanings as commonly understood by those skilled in the art to which this application belongs. The terms used in the specification of the application are only for the purpose of describing specific embodiments and are not intended to limit this application. The terms "including" and "having" and any variations thereof in the specification and claims of this application and the above-mentioned drawings are intended to cover non-exclusive inclusions. The terms "first", "second", etc. in the specification and claims of this application or the above-mentioned drawings are used to distinguish different objects, not to describe a specific order.

[0040] References herein to "embodiments" mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least one embodiment of the present application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0041] At present, the flow process of slurry after entering the stope is regarded as a "black box", and the dynamic settlement and aggregation behavior of waste rock are difficult to observe directly, resulting in the evaluation of filling homogeneity relying on empirical speculation, which cannot meet the needs of precise control in deep complex mining scenarios. To address the above problems, we proposed a method for predicting the homogeneity of full tailings-waste gypsum in narrow and long stopes. When implementing the method, basic physical experimental measurements are first performed on the filling materials. Then, based on similar experimental measurements, the waste rock settlement results of full tailings-waste gypsum in narrow and long access roads under the influence of different factors are measured. According to the settlement results, a slurry homogeneity prediction model is obtained. Finally, numerical simulation is used to analyze the spatial distribution state of full tailings-waste gypsum in narrow and long stopes, as well as the influence of the position and number of the feed port on the slurry homogeneity. Based on the numerical simulation analysis results and the slurry homogeneity prediction model, the optimal filling parameters and feed port position are determined. In this embodiment of the present invention, the physical properties and particle size distribution of waste rock particles are determined through basic physics experiments. Combined with similar simulation experiments, dynamic observations of waste rock settling behavior in narrow and long feedways are conducted. This clarifies the stratified migration mechanism of waste rock during flow. Based on similar experiments and dynamic parameter analysis, a homogeneity prediction model is established that considers the coupling effects of multiple factors, including filling flow rate, waste rock particle size, particle size grading, and feed port location. By quantitatively evaluating the homogeneity of the filling mass using the uniformity coefficient, the uniformity trend of waste rock distribution during slurry flow under different operating conditions can be predicted. This overcomes the limitations of existing technologies, which rely on static experimental data and cannot adapt to complex dynamic conditions.

[0042] An embodiment of the present invention provides a method for predicting the homogeneity of a whole tailings-waste gypsum body in a narrow and long stope. The method for predicting the homogeneity of a whole tailings-waste gypsum body in a narrow and long stope specifically includes:

[0043] S10, obtaining filling materials, performing basic physical experimental measurements on the filling materials, and obtaining basic physical parameters of the filling materials;

[0044] S20, loading the basic physical parameters of the filling material, based on similar experimental measurements of the waste rock settlement results of the full tailings-waste gypsum in a narrow and long passage under the influence of different factors, and deriving a slurry homogeneity prediction model based on the settlement results;

[0045] S30, load the slurry homogeneity prediction model, use numerical simulation to analyze the spatial distribution of the whole tailings and waste gypsum in the narrow and long stope, and the influence of the location and number of the feed port on the slurry homogeneity. Based on the numerical simulation analysis results and the slurry homogeneity prediction model, the optimal filling parameters and feed port location are determined.

[0046] In this embodiment of the present invention, the physical properties and particle size distribution of waste rock particles are determined through basic physics experiments. Combined with similar simulation experiments, dynamic observations of waste rock settling behavior in narrow and long feedways are conducted. This clarifies the stratified migration mechanism of waste rock during flow. Based on similar experiments and dynamic parameter analysis, a homogeneity prediction model is established that considers the coupling effects of multiple factors, including filling flow rate, waste rock particle size, particle size grading, and feed port location. By quantitatively evaluating the homogeneity of the filling mass using the uniformity coefficient, the uniformity trend of waste rock distribution during slurry flow under different operating conditions can be predicted. This overcomes the limitations of existing technologies, which rely on static experimental data and cannot adapt to complex dynamic conditions.

[0047] Example 1

[0048] An embodiment of the present invention provides a method for performing basic physical experiment measurements on a filling material. The method for performing basic physical experiment measurements on a filling material specifically includes:

[0049] S101, conduct physical and chemical property tests on filling materials, including water content, specific gravity, loose / tight bulk density, porosity, and particle size distribution. Figure 1 The figure shows the particle size distribution of the whole tailings and waste rock obtained in Example 1 of the present invention;

[0050] It should be noted that the filling materials include but are not limited to whole tailings, cement, and waste rock. When conducting physicochemical property tests, the test items include but are not limited to measuring the density, chemical composition, particle size composition, moisture content, loose / tight bulk density, porosity, and particle size distribution of the experimental materials; experimentally measuring the contact parameters of the waste rock, including the static friction coefficient, dynamic friction coefficient, and restitution coefficient, etc., and comprehensively testing the physicochemical properties of the filling materials, including a series of key parameters such as moisture content, loose / tight bulk density, porosity, and particle size distribution. Obtaining these parameters helps to gain a deeper understanding of the basic properties of the filling materials and provide detailed basic data for subsequent research and application. For example, understanding the density, chemical composition, and particle size distribution of filling materials such as whole tailings, cement, and waste rock can provide an important basis for performance prediction and quality control of the filling body.

[0051] S102, using the bucket method to test the angle of accumulation of waste rock particles in the filling material;

[0052] Among them, when conducting the reposition angle experiment of waste rock particles, first fill the cylindrical container with waste rock, lift the container filled with waste rock at a uniform speed, let the waste rock particles fall freely, and measure the reposition angle of the waste rock particles after they stabilize.

[0053] S103, designing orthogonal experiments based on the static friction coefficient between waste rock particles, the dynamic friction coefficient between waste rock particles, and the range of the recovery coefficient of waste rock particles, and simulating the waste rock accumulation angle under different contact parameters using discrete element software;

[0054] In this embodiment of the present invention, an orthogonal experiment was designed based on the ranges of the static friction coefficient, kinetic friction coefficient, and restitution coefficient between waste rock particles. Discrete element method software was then used to simulate the waste rock accumulation angle under different contact parameters. This method efficiently explores the influence of different factors on the waste rock accumulation angle. Orthogonal experimental design allows for a rational arrangement of experimental plans and reduces the number of experiments. Discrete element method simulations can further verify and supplement the experimental results, contributing to a deeper understanding of the accumulation behavior of waste rock particles.

[0055] S104, using Design expert software to fit the experimental parameters, obtain the relationship between the three factors and the stacking angle, and bring the measured waste rock stacking angle into the equation to obtain the optimal waste rock particle-waste rock particle static friction coefficient, waste rock particle-waste rock particle dynamic friction coefficient, and waste rock particle recovery coefficient.

[0056] In this example, the acquisition of these parameters provided reliable and effective data for subsequent research. Using Design-Expert software, the experimental parameters were fitted to determine the relationship between the three factors (static friction coefficient, kinetic friction coefficient, and restitution coefficient) and the stacking angle. The measured waste rock stacking angle was then incorporated into the data to determine the optimal contact parameters. This data processing approach fully utilizes the experimental data, establishing a mathematical model through software fitting to more accurately determine the key physical parameters between waste rock particles. This not only improves the accuracy of the experimental results but also provides a more reliable parameter basis for subsequent filling simulations and engineering applications.

[0057] Example 2

[0058] An embodiment of the present invention provides a method for obtaining a slurry homogeneity prediction model based on sedimentation results. The method for obtaining a slurry homogeneity prediction model based on sedimentation results specifically includes:

[0059] S201, select experimental factors and design experiments based on mine requirements;

[0060] S202: Establish a similarity model based on the actual mine stope conditions, calculate an experimental filling flow rate based on the actual mine filling flow rate, and conduct a similar simulation experiment. Inject the mixed slurry into a filling funnel through a pipe so that the slurry flows into the simulated stope. The slurry flows in the simulated stope under the action of its own gravity and initial dynamic force until it is filled to the designated position. During this process, ensure that the liquid level in the filling funnel remains consistent and the filling process is continuous and uninterrupted.

[0061] It should be noted that when selecting experimental factors and designing experiments based on mine needs, the mass concentrations of slurry were 78%, 79%, and 80%, the waste rock content was 50%, 60%, and 70%, and the water reducer content was 0.25%, 0.35%, and 0.45%, respectively. The above experimental factors were selected as independent variables and an orthogonal experiment was designed.

[0062] Figure 2 The diagram of the similarity simulation experiment apparatus obtained in Example 2 of the present invention is shown. When conducting the similarity simulation experiment, the size of the similar model and the speed and flow rate of the material during the simulation are calculated according to the similarity criterion. The similarity criterion is as follows:

[0063] Geometric similarity,

[0064] Similar speed,

[0065] The traffic is similar,

[0066] Where: l is the length scale; L p is the actual stope length, m; L m is the similarity model length, m; λ v is the speed scale; V p is the actual filling flow rate, m / s; V m is the simulated flow velocity of the similar model, m / s; λ Q is the flow rate scale; Q p is the actual filling flow, m 3 / h;Q m is the similar model flow, m 3 / h.

[0067] Then, according to the experimental plan, the whole tailings, waste rock and cement were weighed separately, mixed evenly and then water was added. The mixed materials were stirred with a mixer. After stirring evenly, the pre-weighed water reducer was added and the slurry was continued to be stirred until the slurry was evenly stirred.

[0068] The mixed slurry is injected into the filling funnel through the pipeline so that the slurry flows into the simulated mining field. The slurry will flow in the simulated mining field under the action of its own gravity and initial power until it is filled to the designated position. During this process, it is necessary to ensure that the liquid level in the filling funnel remains consistent and the filling process is continuous and uninterrupted.

[0069] S203, using a sieve with a pore size of 1mm to screen out waste rock with a particle size larger than 1mm, Figure 4 The distribution diagram of 1mm-5mm waste rock obtained in Example 2 of the present invention is shown. Figure 5 The distribution diagram of waste rock with a diameter of more than 5 mm obtained in Example 2 of the present invention is shown. Figure 6 The figure shows the distribution of all particle sizes of waste rock obtained in Example 2 of the present invention. After screening, the waste rock was transferred to an oven for drying. After drying, a sieve with a pore size of 5 mm was used to separate the waste rock into particles of 1 mm to 5 mm and particles larger than 5 mm.

[0070] In the embodiment of the present invention, Figure 3 The diagram shows the locations of sampling points in Example 2 of the present invention. Each time, 1 kg of sample was taken. A sieve with a 1 mm aperture was used to screen out waste rock with a particle size greater than 1 mm. After screening, the sample was transferred to an oven for drying. After drying, a sieve with a 5 mm aperture was used to separate the waste rock into those with a particle size between 1 mm and 5 mm and those with a particle size greater than 5 mm. Based on this, the mass fractions of large-size and small-size waste rock at different locations in the simulated stope were calculated. The deposition of waste rock in the stope under different conditions was analyzed. The uniformity coefficient was calculated using the following formula:

[0071]

[0072] Where: K is the slurry uniformity coefficient; x i is the mass fraction of waste rock at the i-th sampling point, %; x0 is the average mass fraction of sampled waste rock, %; n is the number of sampling points.

[0073] S204, calculating the mass fraction of waste rock particles at different locations using a formula, and analyzing the deposition of large-size waste rock and small-size waste rock at different locations in the simulated stope and the deposition of waste rock in the stope under different conditions;

[0074] S205, after conducting multiple experiments, obtain the uniformity coefficient of the whole tailings-waste gypsum body in the narrow and long stope under different factors, and construct a homogeneity prediction model of the whole tailings-waste gypsum body in the narrow and long stope based on the experimental results.

[0075] In this embodiment, a multivariate nonlinear function is used for regression fitting to obtain a full tailings-waste gypsum homogeneity prediction model, which is as follows:

[0076]

[0077] Where: yi represents the uniformity coefficient; x i are concentration, water reducing agent dosage and waste rock dosage respectively; a0, b i 、c ij is the regression coefficient.

[0078] In the embodiment of the present invention, the distribution of waste rocks of different particle sizes in the stope is analyzed based on similar simulation, and a homogeneity prediction model of the whole tailings-waste rock gypsum in the stope is constructed according to the experimental structure. The model R 2 The model's accuracy was 0.913, and subsequent numerical simulations were used to verify the model's accuracy. In this example, based on the homogeneity prediction model constructed from similar experiments and the influence of waste rock particle spatial distribution and feed port location on slurry homogeneity as determined by numerical simulations, the optimal filling parameters and feed point locations can be determined. This helps in actual mining operations to rationally adjust filling process parameters and feed point placement based on the specific conditions of different mines, improve the uniformity and stability of the filling quality, avoid the degradation of the filling mass due to waste rock settlement, and thus enhance the safety of mining operations.

[0079] Example 3

[0080] The embodiment of the present invention provides a method for analyzing the spatial distribution of full tailings and waste gypsum in a narrow and long stope and the influence of the position and number of feed openings on slurry homogeneity by using numerical simulation. The method for analyzing the spatial distribution of full tailings and waste gypsum in a narrow and long stope and the influence of the position and number of feed openings on slurry homogeneity by using numerical simulation specifically includes:

[0081] S301, construct a numerical model that is consistent with the actual mine and divide the numerical model into grids, where: Figure 7 A diagram of the stope numerical model obtained in Example 3 of the present invention is shown. The simulation using the coupled computational fluid dynamics and discrete element method requires a minimum grid size larger than the waste rock particle size. A grid partitioning strategy with a minimum grid size three times the diameter of the waste rock particle is adopted. This ensures that detailed capture of waste rock particle motion is achieved while avoiding the waste of computing resources caused by an overly dense grid, thus achieving a balance between accuracy and efficiency.

[0082] S302, treating the full tailings slurry as a continuous phase and the waste rock as a discrete phase, setting fluid parameters and boundary conditions in computational fluid dynamics software, and setting waste rock parameters in discrete element software;

[0083] It should be noted that the software involved in this embodiment includes but is not limited to fluent and EDEM.

[0084] S303, coupling setting is performed on the continuous phase and the discrete phase, and the control equation for the interaction between the fluid phase and the discrete phase is set according to actual needs.

[0085] In the embodiment of the present invention, when coupling the continuous phase and the discrete phase, the CFD-DEM coupling method is used to study the distribution of waste rock in the stope, and the fluid simulation software is selected as FLUENT, and the waste rock simulation software is selected as EDEM.

[0086] When setting the fluid parameters and boundary conditions in the computational fluid dynamics software and the waste rock parameters in the discrete element software, the relevant parameters of the fluid and waste rock particles are set in the Fluent software and DEEM software respectively. The Fluent solver selects the pressure solver, the speed is the absolute speed, the time type is the transient solution, and the gravity acceleration is 9.81m / s 2 , along the negative z-axis. The inlet is located at the feed opening and is the velocity inlet. The velocity is set according to the actual filling rate of the mine. The upper surface of the model is the pressure outlet, with an outlet pressure of 0 and directions perpendicular to the boundary surface. All other boundaries are walls, which are set as no-slip boundaries with a roughness of 0.5.

[0087] In the embodiment of the present invention, the turbulence model selects the k-∈ model, and the turbulence multiphase model selects the dispersed one. The waste rock particle size is set to 8 types, namely 1mm, 3mm, 5mm, 6mm, 7mm, 8mm, 10mm, and 12mm. The waste rock particle plant is set at the discharge port. The type of waste rock particle plant is not limited to the number of waste rock particles. The waste rock particles are produced in the form of mass flow. The initial velocity of the waste rock particles is consistent with the initial velocity of the fluid. Its gravitational acceleration is along the negative z-axis, and the magnitude is 9.81m / s. 2 The Hertz-Mindlin model was selected for collisions between waste rock particles and between waste rock particles and the wall, with rolling friction as the friction type. The EDEM mesh was set to three times the minimum waste rock particle size. When coupling Fluent with EDEM, the time step set in Fluent must be an integer multiple of the EDEM time step. Fluid and waste rock parameters were derived based on the basic physical parameters of the filling material described in Example 1.

[0088] The control equations for the interaction between the fluid phase and the discrete phase are set according to actual needs. The fluid phase adopts the Navier-Stokes equation, but additionally includes the feedback term of waste rock particles on the fluid. Its continuity equation and momentum equation are as follows:

[0089]

[0090] Where: ε f is the fluid volume fraction; ρ f is the fluid density, kg / m 3 ;u f is the fluid velocity, m / s; τ f is the fluid stress tensor; g is the acceleration due to gravity, m / s2 ; F fp is the force exerted by the fluid on the waste rock particles, N.

[0091] Collisions between particles obey Newton's second law, and their momentum equation and angular momentum equation are as follows:

[0092]

[0093] Where: m p is the mass of waste rock particles, kg; I P is the moment of inertia of waste rock particles, kg·㎡; w p is the angular velocity of waste rock particles, rad / s; T p F is the resultant moment acting on the waste rock particles; g 、F d 、F c 、F b They are gravity, drag force, collision force between waste rock particles, and buoyancy, N respectively.

[0094] Drag force is the main force acting on waste rock particles by fluid, and is calculated using the Wen&Yu model:

[0095]

[0096] Where: d p is the diameter of waste rock particles, μ f is the fluid viscosity.

[0097] S304: After the simulation is completed, the distribution of waste rock particles in the stope space and the influence of the feed port position on the homogeneity of the entire tailings-waste gypsum are analyzed using discrete element software. After the simulation is completed, the software cross-section function is used to analyze the waste rock distribution at different spatial locations in the stope. This can be used to analyze the influence of different factors on the waste rock distribution. The feed port position can also be changed to analyze the influence of the feed port position on the homogeneity of the entire tailings-waste gypsum. The optimal feed port position is selected based on the results. Figure 8 The particle distribution diagram along the horizontal direction obtained in Example 3 of the present invention is shown. Figure 9 shows the particle distribution diagram along the vertical direction obtained in Example 3 of the present invention;

[0098] S305, determining the spatial distribution of waste rock particles and the location of the discharge port according to the numerical simulation results, and determining the optimal filling parameters and the location of the discharge port based on the numerical simulation analysis results and the slurry homogeneity prediction model.

[0099] In this embodiment, by optimizing the filling parameters and the location of the feed opening, it is possible to effectively reduce the uneven settlement of waste rock and the heterogeneity of the filling body, thereby reducing the risk of mine production accidents caused by filling quality problems. At the same time, improving filling efficiency and quality helps to extend the service life of the mine and reduce the overall production cost of the mine. In addition, through high-precision CFD-DEM coupled simulation and dynamic parameter optimization, this invention solves the industry pain points of invisible waste rock distribution in narrow and long stopes and the reliance on experience in feed opening design. It provides an innovative technical means to improve the homogeneity of the filling body and ensure the safe and efficient mining of deep mines, and has significant engineering application value and promotion prospects.

[0100] In summary, the present invention provides a method for predicting the homogeneity of a full tailings-waste gypsum body in a narrow and long mining area. In an embodiment of the present invention, the physical properties and particle size distribution of waste rock particles are obtained through basic physical experiments. Combined with similar simulation experiments, the sedimentation behavior of waste rock in the narrow and long access road is dynamically observed, clarifying the stratified migration mechanism of waste rock during the flow process. Based on similar experiments and dynamic parameter analysis, a homogeneity prediction model is established that considers the coupling of multiple factors such as filling flow rate, waste rock particle size, particle size grading, and feed port location. By quantitatively evaluating the homogeneity of the filling body through the uniformity coefficient, the uniformity change trend of waste rock distribution during slurry flow under different working conditions can be predicted, which solves the limitation of existing technologies that rely on static experimental data and cannot adapt to complex dynamic conditions.

[0101] It should be noted that for the aforementioned embodiments, for simplicity of description, they are all expressed as a series of action combinations. However, those skilled in the art should be aware that the present invention is not limited by the order of the actions described, because according to the present invention, certain steps may be performed in other orders or simultaneously. Secondly, those skilled in the art should also be aware that the embodiments described in this specification are all preferred embodiments, and the actions and modules involved are not necessarily required by the present invention.

[0102] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the scope of protection of the invention. Obviously, the embodiments described are only some embodiments of the present invention, rather than all embodiments. Based on these embodiments, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in this field can still combine, add, delete or make other adjustments to the features in the various embodiments of the present invention according to the circumstances without conflict, without making creative work, so as to obtain different other technical solutions that do not deviate from the concept of the present invention in essence, and these technical solutions also fall within the scope of protection of the present invention.

Claims

1. A method for predicting the homogeneity of full tailings-waste gypsum in a narrow and long stope, characterized in that: The method comprises: S10, obtaining filling materials, performing basic physical experimental measurements on the filling materials, and obtaining basic physical parameters of the filling materials; S20, loading the basic physical parameters of the filling material, based on similar experimental measurements of the waste rock settlement results of the full tailings-waste gypsum in a narrow and long passage under the influence of different factors, and deriving a slurry homogeneity prediction model based on the settlement results; S30, load the slurry homogeneity prediction model, use numerical simulation to analyze the spatial distribution of the whole tailings and waste gypsum in the narrow and long stope, and the influence of the location and number of the feed port on the slurry homogeneity. Based on the numerical simulation analysis results and the slurry homogeneity prediction model, the optimal filling parameters and feed port location are determined.

2. The method for predicting homogeneity of full tailings-waste gypsum in a narrow and long stope according to claim 1, characterized in that: The method for performing basic physical experimental measurements on the filling material comprises: S101, conduct physical and chemical property tests on filling materials, including water content, specific gravity, loose / tight bulk density, porosity, and particle size distribution; S102, using the bucket method to test the angle of accumulation of waste rock particles in the filling material; S103, designing orthogonal experiments based on the static friction coefficient between waste rock particles, the dynamic friction coefficient between waste rock particles, and the range of the recovery coefficient of waste rock particles, and simulating the waste rock accumulation angle under different contact parameters using discrete element software; S104, using Design expert software to fit the experimental parameters, obtain the relationship between the three factors and the stacking angle, and bring the measured waste rock stacking angle into the equation to obtain the optimal waste rock particle-waste rock particle static friction coefficient, waste rock particle-waste rock particle dynamic friction coefficient, and waste rock particle recovery coefficient.

3. The method for predicting homogeneity of full tailings-waste gypsum in a narrow and long stope according to claim 1, characterized in that: The method for obtaining a slurry homogeneity prediction model based on sedimentation results comprises: S201, select experimental factors and design experiments based on mine requirements; S202: Establish a similarity model based on the actual mine stope conditions, calculate an experimental filling flow rate based on the actual mine filling flow rate, and conduct a similar simulation experiment. Inject the mixed slurry into a filling funnel through a pipe so that the slurry flows into the simulated stope. The slurry flows in the simulated stope under the action of its own gravity and initial dynamic force until it is filled to the designated position. S203, using a 1 mm pore size sieve to screen out waste rock with a particle size larger than 1 mm, and then transferring the waste rock to an oven for drying. After drying, using a 5 mm pore size sieve to separate the waste rock into particles between 1 mm and 5 mm and particles larger than 5 mm; S204, calculating the mass fraction of waste rock particles at different locations using a formula, and analyzing the deposition of large-size waste rock and small-size waste rock at different locations in the simulated stope and the deposition of waste rock in the stope under different conditions; S205, after conducting multiple experiments, obtain the uniformity coefficient of the whole tailings-waste gypsum body in the narrow and long stope under different factors, and construct a homogeneity prediction model of the whole tailings-waste gypsum body in the narrow and long stope based on the experimental results.

4. The method for predicting homogeneity of full tailings-waste gypsum in a narrow and long stope according to claim 1, characterized in that: The numerical simulation method is used to analyze the spatial distribution of the whole tailings-waste gypsum in the narrow and long stope and the influence of the location and number of the feed openings on the slurry homogeneity, including: S301, constructing a numerical model that is consistent with the actual mine conditions and performing grid division on the numerical model; S302, treating the full tailings slurry as a continuous phase and the waste rock as a discrete phase, setting fluid parameters and boundary conditions in computational fluid dynamics software, and setting waste rock parameters in discrete element software; S303, coupling setting is performed on the continuous phase and the discrete phase, and the control equation for the interaction between the fluid phase and the discrete phase is set according to actual needs.

5. The method for predicting homogeneity of full tailings-waste gypsum in a narrow and long stope according to claim 4, characterized in that: The method of using numerical simulation to analyze the spatial distribution of full tailings and waste gypsum in a narrow and long stope and the influence of the location and number of feed openings on slurry homogeneity also includes: S304: After the simulation is completed, the distribution of waste rock particles in the stope space and the influence of the feed opening position on the homogeneity of the whole tailings-waste rock mass are analyzed using discrete element software; S305, determining the spatial distribution of waste rock particles and the location of the discharge port according to the numerical simulation results, and determining the optimal filling parameters and the location of the discharge port based on the numerical simulation analysis results and the slurry homogeneity prediction model.

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