A method for predicting the homogeneity of a full tailings-waste rock paste in a narrow stope

Abstract

The application discloses a kind of full tailings-waste rock paste body in long and narrow stope homogeneity prediction method, belong to mine filling technical field, solve the dynamic settlement and aggregation behavior of waste rock at present stage difficult to directly observe, resulting in filling body homogeneity evaluation relies on experience speculation problem, the method includes that filling material is carried out basic physical experiment measurement, based on similar experiment measurement different factor influence under full tailings-waste rock paste body in long and narrow drift waste rock settlement result, using numerical simulation analysis full tailings-waste rock paste body in long and narrow stope spatial distribution state and the influence of discharge port position, quantity to slurry homogeneity;The application is based on similarity experiment and dynamic parameter analysis, establishes the homogeneity prediction model considering the coupling effect of multiple factors such as filling flow, waste rock particle size, particle size gradation, discharge port position and the like. Through uniformity coefficient quantitative evaluation filling body homogeneity, can predict the uniformity change trend of waste rock distribution in slurry flow process under different working conditions.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of mine filling, and particularly relates to a method for predicting the homogeneity of full-tail sand-waste rock paste in a narrow stope. BACKGROUND

[0002] With the continuous growth of global demand for mineral resources and the gradual depletion of shallow resources, deep ore body mining has become an inevitable direction of the development of the mining industry. However, deep mining faces the challenges of high stress, high ground temperature and complex geological conditions, and higher requirements are put forward for the stability, homogeneity and safety of the filling body. In the traditional filling technology, full-tail sand-waste rock paste is widely used in underground goaf filling due to its environmental protection, economic and mechanical performance advantages. 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 cementing material and saving costs. However, the density of waste rock is significantly higher than that of the slurry matrix, and it is prone to sedimentation and stratification during long-distance transportation and narrow access filling, resulting in a decrease in waste rock content and uneven structure of the filling body at the far end, and further causing problems such as insufficient strength of the filling body, settlement deformation and even cracking, which seriously affect the safety of mining and the efficiency of resource recovery.

[0003] On the other hand, the access 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 loss. However, with the increase of the length of the access, the flow characteristics of full-tail sand-waste rock paste in a narrow stope tend to be complex, and the slurry flow resistance and waste rock sedimentation effect work together to easily form a "flow uneven" phenomenon, which is manifested as uneven distribution of slurry surface layer and bottom aggregate, and serious local segregation. Current researches mainly focus on the optimization of the ratio of full-tail sand or classified tailings and the characterization of the strength of static filling body, and the research on the homogeneity evolution mechanism of waste rock-full-tail sand paste in the dynamic flow process is seriously insufficient. Existing researches are mostly based on the performance test of slurry under static or semi-static conditions, and lack of theoretical models and technical means for real-time prediction of waste rock migration law, slurry stratification dynamics and homogeneity under flow conditions. Especially in actual engineering, the flow process of slurry after entering the stope is regarded as a "black box", and the dynamic sedimentation and aggregation behavior of waste rock is difficult to observe directly, which leads to the dependence of filling body homogeneity evaluation on experience and speculation, and cannot meet the needs of precise regulation and control in deep complex mining scenarios. In view of the above problems, we propose a method for predicting the homogeneity of full-tail sand-waste rock paste in a narrow stope. SUMMARY

[0004] The present application aims at the deficiencies of the prior art, and provides a full tailings-waste rock paste body homogeneity prediction method in a narrow stope, which solves the problem that the flow process of the slurry into the stope is regarded as a "black box", the dynamic settling and gathering behavior of the waste rock is difficult to directly observe, and the filling body homogeneity evaluation depends on experience speculation, thereby failing to meet the precise regulation and control requirements in the deep complex mining scene.

[0005] At present, the flow process of the slurry into the stope is regarded as a "black box", the dynamic settling and gathering behavior of the waste rock is difficult to directly observe, and the filling body homogeneity evaluation depends on experience speculation, thereby failing to meet the precise regulation and control requirements in the deep complex mining scene. In view of the above problems, the present application provides a full tailings-waste rock paste body homogeneity prediction method in a narrow stope, which comprises the following steps:

[0006] The present application is implemented in the following way: a full tailings-waste rock paste body homogeneity prediction method in a narrow stope, which comprises the following steps:

[0007] S10, obtaining the filling material, and performing basic physical experiment measurement on the filling material to obtain basic physical parameters of the filling material;

[0008] S20, loading the basic physical parameters of the filling material, measuring the waste rock settling results of the full tailings-waste rock paste body in a narrow passageway under the influence of different factors based on a similar experiment, and obtaining a slurry homogeneity prediction model according to the settling results;

[0009] S30, loading the slurry homogeneity prediction model, using numerical simulation to analyze the spatial distribution state of the full tailings-waste rock paste body in the narrow stope and the influence of the position and number of the discharge port on the slurry homogeneity, determining the optimal filling parameters and the position of the discharge port based on the numerical simulation analysis results and the slurry homogeneity prediction model.

[0010] Preferably, the method for measuring the basic physical experiment of the filling material comprises:

[0011] S101, performing physicochemical property testing on the filling material, and the physicochemical property testing includes water content ratio, loose / tight bulk density, porosity, and particle size distribution;

[0012] S102, using the bucket method to perform pile-up angle experiment determination on the waste rock particles in the filling material;

[0013] S103, designing an orthogonal experiment based on the static friction coefficient between the waste rock particles, the dynamic friction coefficient between the waste rock particles, and the range of the waste rock particle recovery coefficient, and simulating the waste rock pile-up angle under different contact parameters through the discrete element software;

[0014] S104, fitting the experimental parameters by using the Design expert software to obtain the relationship between the three factors and the pile-up angle, and bringing the measured waste rock pile-up angle 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 the slurry homogeneity prediction model according to the settlement results comprises:

[0016] S201, selecting experimental factors and designing experiments based on the mine demand;

[0017] S202, establishing a similar model according to the actual stope situation of the mine, calculating the experimental filling flow based on the actual filling flow of the mine and performing a similar simulation experiment, injecting the mixed slurry into the filling funnel through the pipeline to make the slurry flow into the simulated stope, and the slurry flows in the simulated stope under the action of its own gravity and initial power until it is filled to the specified position;

[0018] S203, screening out waste rock with a particle size greater than 1 mm by using a sieve with a pore size of 1 mm, transferring to an oven for drying treatment after the screening is completed, and dividing the waste rock into 1 mm-5 mm and greater than 5 mm after drying by using a sieve with a pore size of 5 mm;

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

[0020] S205, obtaining the uniformity coefficients of the full tailings-waste rock paste body in the narrow stope under different factors after multiple experiments, and constructing a homogeneity prediction model of the full tailings-waste rock paste body in the narrow stope according to the experimental results.

[0021] Preferably, the method for analyzing the spatial distribution state of the full tailings-waste rock paste body in the narrow stope and the influence of the position and number of the discharge port on the homogeneity of the paste body by numerical simulation is adopted, comprising:

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

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

[0024] S303, coupling the continuous phase and the discrete phase, and setting the interaction control equation of the fluid phase and the discrete phase according to the actual demand.

[0025] S304, after the simulation is completed, analyzing the influence of the spatial position of the waste rock particles in the stope and the position of the discharge port on the homogeneity of the full tailings-waste rock paste body by the discrete element software;

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

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

[0028] In the embodiments of the present application, the physical characteristics and particle size distribution of the waste rock particles are obtained through basic physical experiments, the waste rock sedimentation behavior in the narrow access is dynamically observed through similar simulation experiments, the stratified migration mechanism of the waste rock in the flow process is clarified, and a homogeneity prediction model considering the coupling of multiple factors such as filling flow, waste rock particle size, particle size gradation, and discharge port position is established based on similar experiments and dynamic parameter analysis. The homogeneity of the filling body is quantitatively evaluated by the uniformity coefficient, the uniformity variation trend of the waste rock distribution in the paste flow process under different working conditions can be predicted, and the limitations of the prior art relying on static experimental data and being unable to adapt to complex dynamic conditions are solved.

[0029] The application provides a method for predicting the homogeneity of full tailings-waste rock paste in a narrow stope, and the method comprises the following steps: constructing a stope model in accordance with the actual mine by combining physical experiments with numerical simulation, establishing a homogeneity prediction model of the full tailings-waste rock paste in the narrow stope by studying the influence of different factors on the homogeneity of the slurry, and analyzing the influence of the spatial distribution state and the position of the feeding point on the homogeneity by numerical simulation, so as to realize the homogeneity prediction of the full tailings-waste rock paste in the narrow stope and the determination of the optimal filling parameters. BRIEF DESCRIPTION OF DRAWINGS

[0030] Figure 1 A particle size distribution diagram of the full tailings and waste rock obtained in embodiment 1 of the application is shown.

[0031] Figure 2 A similar simulation experiment device diagram obtained in embodiment 2 of the application is shown.

[0032] Figure 3 A sampling point position diagram in embodiment 2 of the application is shown.

[0033] Figure 4 A 1mm-5mm waste rock distribution diagram obtained in embodiment 2 of the application is shown.

[0034] Figure 5 A >5mm waste rock distribution diagram obtained in embodiment 2 of the application is shown.

[0035] Figure 6 A full particle size waste rock distribution diagram obtained in embodiment 2 of the application is shown.

[0036] Figure 7 A stope numerical model diagram obtained in embodiment 3 of the application is shown.

[0037] Figure 8 A particle distribution diagram along a horizontal direction obtained in embodiment 3 of the application is shown.

[0038] Figure 9 A particle distribution diagram along a vertical direction obtained in embodiment 3 of the application is shown. DETAILED DESCRIPTION

[0039] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs; the terminology used in the description herein is for describing particular embodiments only and is not intended to be limiting of the application; the description and the claims herein and the above description of drawings herein together with the drawings attached hereto describe and illustrate preferred embodiments exemplifying the application. The use herein of terms such as "including", "comprising", or "having" is used generically and are intended to encompass the terms "including", "comprising", and "having" grammatical equivalents thereof as well as any other term or phrase that connotes the same or similar meaning. The use herein of terms such as "first", "second" and the like is used generically and is not intended to connote a specific order or priority.

[0040] Reference to an "embodiment" herein means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the application. The appearances of the phrase in various places in the specification are not necessarily all referring to the same embodiment, nor are they necessarily mutually exclusive of one another. As will be apparent to those of ordinary skill in the art, embodiments described herein can be combined with other embodiments.

[0041] At present, the flow process of the slurry after entering the stope is regarded as a "black box", and the dynamic settling and aggregation behavior of the waste rock are difficult to directly observe, resulting in that the evaluation of the homogeneity of the filling body depends on experience speculation, and the demand for precise regulation under the complex mining scene in the deep part cannot be met. In view of the above problems, a homogeneity prediction method of full tailings-waste rock paste in a narrow stope is provided. When the method is implemented, firstly, the basic physical experiment of the filling material is measured, then the waste rock settling results of the full tailings-waste rock paste in the narrow passageway under the influence of different factors are measured based on the similar experiment, the slurry homogeneity prediction model is obtained according to the settling results, finally, the spatial distribution state of the full tailings-waste rock paste in the narrow stope and the influence of the position and number of the discharge port on the slurry homogeneity are analyzed by numerical simulation, and the best filling parameters and the position of the discharge port are determined based on the analysis results of the numerical simulation. In the embodiment of the application, the physical characteristics and particle size distribution of the waste rock particles are obtained through the basic physical experiment, the waste rock settling behavior in the narrow passageway is dynamically observed by combining the similar simulation experiment, the stratification migration mechanism of the waste rock in the flow process is determined, and the homogeneity prediction model considering the coupling of the filling flow, the waste rock particle size, the particle size gradation, the position of the discharge port and other factors is established based on the similar experiment and dynamic parameter analysis. The homogeneity of the filling body is quantitatively evaluated by the uniformity coefficient, the uniformity change trend of the waste rock distribution in the slurry flow process under different working conditions can be predicted, and the limitation that the prior art relies on static experimental data and cannot adapt to complex dynamic conditions is solved.

[0042] The embodiment of the application provides a homogeneity prediction method of full tailings-waste rock paste in a narrow stope.

[0043] S10, obtaining the filling material, performing basic physical experiment measurement on the filling material, and obtaining basic physical parameters of the filling material;

[0044] S20, loading the basic physical parameters of the filling material, measuring the waste rock settling results of the full tailings-waste rock paste in the narrow passageway under the influence of different factors based on the similar experiment, and obtaining a slurry homogeneity prediction model according to the settling results;

[0045] S30, load the slurry homogeneity prediction model, analyze the spatial distribution state of the full tailings-waste rock paste body in the narrow stope and the influence of the position and number of the discharge port on the slurry homogeneity by numerical simulation, and determine the optimal filling parameters and the position of the discharge port based on the numerical simulation analysis results and the slurry homogeneity prediction model.

[0046] In the embodiment of the present application, the physical properties and particle size distribution of the waste rock particles are obtained through basic physical experiments, the settling behavior of the waste rock in the narrow access is dynamically observed through similar simulation experiments, the stratified migration mechanism of the waste rock in the flow process is determined, and based on the similar experiments and dynamic parameter analysis, a homogeneity prediction model considering the coupling of multiple factors such as filling flow, waste rock particle size, particle size gradation, and discharge port position is established. The homogeneity of the filling body is quantitatively evaluated by the uniformity coefficient, the uniformity variation trend of the waste rock distribution in the slurry flow process under different working conditions can be predicted, and the limitations of the prior art relying on static experimental data and being unable to adapt to complex dynamic conditions are solved.

[0047] Embodiment 1

[0048] The embodiment of the present application provides a method for measuring the basic physical experiments of filling materials, and the method for measuring the basic physical experiments of filling materials specifically comprises:

[0049] S101, performing physicochemical property testing on the filling materials, and the physicochemical property testing includes water content ratio, loose / tight bulk density, porosity, and particle size gradation, Figure 1 The particle size distribution diagram of the full tailings and waste rock obtained in Embodiment 1 of the present application is shown;

[0050] It should be noted that the filling materials include but are not limited to full tailings, cement, and waste rock, and when the physicochemical property testing is performed, the test items include but are not limited to measuring the density, chemical composition, particle size composition, water content ratio, loose / tight bulk density, porosity, and particle size gradation of the experimental materials; the contact parameters of the waste rock are measured through experiments, including the static friction coefficient, dynamic friction coefficient, and recovery coefficient; and a series of key parameters such as the water content ratio, loose / tight bulk density, porosity, and particle size gradation are comprehensively tested through the physicochemical property testing of the filling materials. The acquisition of these parameters helps to deeply understand the basic properties of the filling materials, and provides detailed basic data for subsequent research and application. For example, understanding the density, chemical composition, and particle size composition of the filling materials such as full tailings, cement, and waste rock can provide an important basis for performance prediction and quality control of the filling body.

[0051] S102, performing pile-up angle experiment determination on the waste rock particles in the filling materials by using the bucket method;

[0052] Wherein, when the waste rock particles are subjected to the packing angle experiment, firstly, the waste rock is filled in the cylindrical container, the container filled with the waste rock is uniformly lifted, the waste rock particles are allowed to freely fall, and the packing angle of the waste rock particles is measured after being stabilized.

[0053] In S103, the orthogonal experiment is designed based on the static friction coefficient between the waste rock particles, the dynamic friction coefficient between the waste rock particles and the recovery coefficient range of the waste rock particles, and the waste rock packing angle under different contact parameters is simulated by the discrete element software.

[0054] In the embodiment of the present application, the orthogonal experiment is designed based on the static friction coefficient, the dynamic friction coefficient and the recovery coefficient range between the waste rock particles, and the waste rock packing angle under different contact parameters is simulated by the discrete element software. This method can efficiently explore the influence law of different factors on the waste rock packing angle. The orthogonal experiment design can reasonably arrange the experimental scheme, reduce the number of experiments, and the discrete element simulation can further verify and supplement the experimental results, which is helpful to deeply understand the packing behavior of the waste rock particles.

[0055] In S104, the experimental parameters are fitted by using the Design expert software, the relationship between the three factors and the packing angle is obtained, and 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 are obtained by bringing the measured waste rock packing angle.

[0056] In the embodiment, the above parameters are obtained, which provides reliable and effective data for subsequent research, and the experimental parameters are fitted by using the Design-expert software, the relationship between the three factors (static friction coefficient, dynamic friction coefficient and recovery coefficient) and the packing angle is obtained, and the optimal contact parameters are obtained by bringing the measured waste rock packing angle. This data processing method can fully utilize the experimental data, and a mathematical model is established by software fitting, so that the key physical parameters between the waste rock particles can be more accurately determined. This not only improves the accuracy of the experimental results, but also provides more reliable parameter basis for subsequent filling simulation and engineering application.

[0057] Embodiment 2

[0058] The embodiment of the present application provides a method for obtaining a slurry homogeneity prediction model according to a sedimentation result, and the method specifically comprises the following steps:

[0059] In S201, experimental factors are selected and experiments are designed based on mine requirements.

[0060] S202, a similar model is established according to the actual stope situation of the mine, the experimental filling flow is obtained according to the actual filling flow of the mine and a similar simulation experiment is carried out, the mixed slurry is injected into the filling funnel through a pipeline to flow into the simulated stope, the slurry flows in the simulated stope under the action of its own gravity and initial power until it is filled to the designated position, and the liquid level of the filling funnel is kept consistent and the filling process is continuous and uninterrupted in the process.

[0061] It should be noted that when the experimental factors are selected and the experiment is designed based on the mine demand, the mass concentration of the slurry is 78%, 79% and 80%, respectively, the waste rock content is 50%, 60% and 70%, respectively, and the water reducing agent content is 0.25%, 0.35% and 0.45%, respectively. The above experimental factors are selected as independent variables and orthogonal experiments are designed.

[0062] Figure 2 The similar simulation experiment device diagram obtained by the embodiment 2 of the application is shown, when the similar simulation experiment is carried out, the size of the similar model and the speed and flow of the material during simulation are calculated according to the similarity criterion, and the similarity criterion is as follows:

[0063] Geometric similarity,

[0064] Velocity similarity,

[0065] Flow similarity,

[0066] In the formula: λ l is the length scale; L p is the actual stope length, m; L m is the length of the similar model, m; λ v is the velocity scale; V p is the actual filling flow rate, m / s; V m is the similar model simulation flow rate, m / s; λ Q is the flow 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 scheme, the whole tailings, waste rock and cement are weighed, and the three are mixed uniformly, then water is added, the mixed material is stirred by a stirrer, and then the pre-weighed water reducing agent is added, and the slurry is continuously stirred until the slurry is uniformly stirred.

[0068] The mixed slurry is injected into the filling funnel through a pipeline to flow into the simulated stope, and the slurry flows in the simulated stope under the action of gravity and initial power until the slurry is filled to the designated position, and the liquid level of the filling funnel is kept consistent and the filling process is continuous and uninterrupted.

[0069] S203, waste rock with a particle size greater than 1 mm is screened out by using a sieve with a pore size of 1 mm, Figure 4 A 1mm-5mm waste rock distribution diagram obtained in the embodiment 2 of the application is shown, Figure 5 A >5mm waste rock distribution diagram obtained in the embodiment 2 of the application is shown, and Figure 6 A full particle size waste rock distribution diagram obtained in the embodiment 2 of the application is shown, and after the screening is completed, the waste rock is transferred to an oven for drying treatment, and after drying, the waste rock is divided into 1mm-5mm and >5mm by using a sieve with a pore size of 5mm;

[0070] In the embodiment of the application, Figure 3 A sampling point position diagram in the embodiment 2 of the application is shown; 1kg is sampled each time, waste rock with a particle size greater than 1mm is screened out by using a sieve with a pore size of 1mm, and after the screening is completed, the waste rock is transferred to an oven for drying treatment, and after drying, the waste rock is divided into 1mm-5mm and >5mm by using a sieve with a pore size of 5mm, so as to calculate the mass fraction of large particle size waste rock and small particle size waste rock at different positions in the simulated stope, analyze the deposition of waste rock in the stope under different conditions, and the uniformity coefficient calculation formula is as follows:

[0071]

[0072] In the formula, K is the uniformity coefficient of the slurry; x i is the mass fraction of waste rock at the ith sampling point, %; x0 is the average mass fraction of the sampled waste rock, %; and n is the number of sampling points.

[0073] S204, the mass fraction of waste rock particles at different positions is calculated by the formula, and the deposition of large particle size waste rock and small particle size waste rock at different positions in the simulated stope and the deposition of waste rock in the stope under different conditions are analyzed;

[0074] S205, the uniformity coefficient of the full tailings-waste rock paste in the narrow stope under different factors is obtained after multiple experiments, and a homogeneity prediction model of the full tailings-waste rock paste in the narrow stope is constructed according to the experimental results.

[0075] In the embodiment, a multivariate nonlinear function is used for regression fitting to obtain a full tailings-waste rock paste homogeneity prediction model, and the prediction model is as follows:

[0076]

[0077] In the formula, yi represents uniform coefficient; x i respectively represent concentration, water-reducing agent content and waste rock content; a0, b i , c ij are regression coefficients.

[0078] In the embodiment of the present application, the distribution of waste rocks with different particle sizes in the stope is analyzed based on the similarity simulation, and a homogeneity prediction model of the full tailings-waste rock paste body in the stope is constructed according to the experimental structure, the model R 2 is 0.913, and the accuracy of the model can be verified according to subsequent numerical simulation. In the embodiment, the homogeneity prediction model constructed based on the similarity experiment and the spatial distribution of waste rock particles and the influence law of the position of the discharge port on the homogeneity of the paste obtained by numerical simulation can determine the optimal filling parameters and the position of the discharge point. This helps to reasonably adjust the filling process parameters and the arrangement of the discharge point according to the specific conditions of different mines in actual mining, improve the uniformity and stability of the filling quality, avoid the problem of quality decline of the filling body caused by the settlement of waste rocks, and thus enhance the safety of the stoping operation.

[0079] Embodiment 3

[0080] The embodiment of the present application provides a method for analyzing the spatial distribution state of the full tailings-waste rock paste body in a narrow stope and the influence of the position and number of the discharge port on the homogeneity of the paste by numerical simulation, which specifically comprises:

[0081] S301, a numerical model consistent with the actual mine is constructed, and the numerical model is meshed, wherein, Figure 7 Fig. 3 shows the numerical model of the stope obtained in the embodiment 3 of the present application, wherein when the method of coupling computational fluid dynamics and discrete elements is used for simulation, the minimum grid size needs to be greater than the size of the waste rock particles, and the grid division strategy of using a minimum grid size of 3 times the diameter of the waste rock particles is adopted, which not only ensures the capture of the details of the movement of the waste rock particles, but also avoids the waste of computing resources caused by too dense grid, and balances the precision and efficiency;

[0082] S302, the full tailings paste is regarded as a continuous phase, and the waste rock is regarded as a discrete phase, the fluid parameters and boundary conditions are set in the computational fluid dynamics software, and the waste rock parameters are set in the discrete element software;

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

[0084] S303, the continuous phase and the discrete phase are coupled and set, and the interaction control equation of the fluid phase and the discrete phase is set according to the actual demand.

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

[0086] In the computational fluid dynamics software, the fluid parameters and boundary conditions are set, and the waste rock parameters are set in the discrete element software. The relevant parameters of the fluid and the waste rock particles are set in the Fluent software and the DEEM software, respectively. The pressure solver is selected for the Fluent solver, the velocity is absolute velocity, the time type is transient solution, the gravitational acceleration is 9.81 m / s 2 , and the direction is along the negative z-axis. The inlet is arranged at the discharge port, which is a velocity inlet. The velocity is set according to the actual filling speed of the mine. The upper surface of the model is a pressure outlet, and the outlet pressure is 0. The directions are all perpendicular to the boundary surface. The other boundaries are all walls, which are set as no-slip boundaries with a roughness of 0.5.

[0087] In the embodiment of the present application, the turbulent flow model is selected as k-∈ model, and the turbulent multiphase model is selected as dispersion. The particle size of the waste rock is set to 8 kinds of particle sizes, which are 1 mm, 3 mm, 5 mm, 6 mm, 7 mm, 8 mm, 10 mm and 12 mm. The waste rock particle factory is arranged at the discharge port, and the waste rock particle factory type is not limited to the number of waste rock particles. The waste rock particles are generated in the form of mass flow, and the initial velocity of the waste rock particles is consistent with the initial velocity of the fluid. The gravitational acceleration of the waste rock particles is along the negative z-axis, and the size is 9.81 m / s 2 . The collision model between the waste rock particles and the wall is selected as Hertz-Mindlin model, and the friction type is rolling friction. In EDEM, the grid is set to three times the size of the smallest waste rock particle. When Fluent and EDEM are coupled, the time step in Fluent needs to be an integer multiple of the time step in EDEM. The fluid and waste rock related parameters are based on the physical parameters of the filling material in embodiment 1.

[0088] According to the actual demand, the fluid phase and the discrete phase interaction control equation are set. The fluid phase adopts Navier-Stokes equation, but additionally contains the feedback term of the waste rock particles to the fluid. The continuity equation and the momentum equation are as follows:

[0089]

[0090] In the formula, 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 gravitational acceleration, m / s2 ;F fp is the force of fluid on the waste rock particle, N.

[0091] The collision between particles obeys Newton's second law, and the momentum equation and angular momentum equation are as follows:

[0092]

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

[0094] The drag force is the main force of the fluid on the waste rock particle, and the Wen&Yu model is used for calculation:

[0095]

[0096] In the formula: d p is the diameter of the waste rock particle, μ f is the viscosity of the fluid.

[0097] S304, after the simulation is finished, the distribution of the waste rock particles in the stope space position and the influence of the discharge port position on the homogeneity of the whole tailings-waste rock paste are analyzed by the discrete element software, the distribution of the waste rock at different spatial positions in the stope is analyzed after the simulation is finished by using the section function of the software, and the influence of different factors on the distribution of the waste rock can be analyzed, the discharge port position can be replaced to analyze the influence of the discharge port position on the homogeneity of the whole tailings-waste rock paste, and the best discharge port position is selected according to the results, Figure 8 shows the particle distribution graph along the horizontal direction obtained in embodiment 3 of the present application, and Figure 9 shows the particle distribution graph along the vertical direction obtained in embodiment 3 of the present application;

[0098] S305, the spatial distribution of the waste rock particles and the discharge port position are determined according to the numerical simulation results, and the best filling parameter and the discharge port position are determined based on the numerical simulation analysis results and the slurry homogeneity prediction model.

[0099] In the embodiment, by optimizing the filling parameters and the discharge port position, uneven settlement of waste rock and heterogeneity of the filling body can be effectively reduced, and the risk of mine production accidents caused by filling quality problems can be reduced. At the same time, the filling efficiency and quality are improved, which helps to prolong the service life of the mine, reduce the overall production cost of the mine, and the application solves the industry pain points of invisible waste rock distribution in the narrow stope and experience-dependent discharge port design, provides an innovative technical means for improving the homogeneity of the filling body and ensuring safe and efficient mining in the deep mine, and has significant engineering application value and popularization prospect.

[0100] In summary, the application provides a full tailings-waste rock gypsum body homogeneity prediction method in a narrow stope. In the embodiment, the physical characteristics and particle size distribution of the waste rock particles are obtained through basic physical experiments, the waste rock settlement behavior in the narrow passageway is dynamically observed through similar simulation experiments, the stratification migration mechanism of the waste rock in the flow process is determined, and based on the similar experiments and dynamic parameter analysis, a homogeneity prediction model considering the coupling of multiple factors such as filling flow, waste rock particle size, particle size gradation, discharge port position, etc. is established. The homogeneity of the filling body is quantitatively evaluated by the uniformity coefficient, the uniformity change trend of the waste rock distribution in the slurry flow process under different working conditions can be predicted, and the limitations of the prior art relying on static experimental data and being unable to adapt to complex dynamic conditions are solved.

[0101] It should be noted that, for the foregoing embodiments, in order to simply describe, they are all expressed as a series of action combinations, but those skilled in the art should know that the application is not limited by the action order described, because according to the application, certain steps can be performed in other order or simultaneously. Secondly, those skilled in the art should know that the embodiments described in the specification are all preferred embodiments, and the actions and modules involved are not necessarily necessary for the application.

[0102] The above embodiments are only used to illustrate the technical solutions of the application, and not to limit the protection scope of the application. Obviously, the described embodiments are only some of the embodiments of the application, not all the embodiments. Based on these embodiments, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of the application. Although the application is described in detail with reference to the above embodiments, those skilled in the art can still combine, delete or make other adjustments to the features in the embodiments of the application according to the circumstances without making creative labor, so as to obtain different other technical solutions which do not deviate from the concept of the application in essence, and these technical solutions also belong to the scope of the application to be protected.

Claims

1. A method for predicting the homogeneity of tailings-waste gypsum bodies in narrow and elongated mining areas, characterized in that, The method includes: S10, Obtain the filling material, perform basic physical experiments on the filling material, and obtain the basic physical parameters of the filling material; S20, load the basic physical parameters of the filling material, and measure the waste rock settling results of the whole tailings-waste gypsum body in the narrow passage under the influence of different factors based on similar experimental measurements. Based on the settling results, a slurry homogeneity prediction model is obtained. S30, Load the slurry homogeneity prediction model, use numerical simulation to analyze the spatial distribution of tailings-waste gypsum in a narrow mining area and the influence of the location and quantity of the discharge port on the slurry homogeneity, and determine the optimal filling parameters and discharge port location based on the numerical simulation analysis results and the slurry homogeneity prediction model. The method for obtaining a slurry homogeneity prediction model based on sedimentation results includes: S201, Select experimental factors and design experiments based on mine requirements; S202. A similar model is established based on the actual mining conditions. The experimental filling flow rate is calculated based on the actual filling flow rate of the mine and a similar simulation experiment is conducted. The mixed slurry is injected into the filling funnel through the pipeline so that the slurry flows into the simulated mining area. The slurry flows in the simulated mining area under its own gravity and initial power until it fills the designated position. S203, waste rock with a particle size greater than 1mm is screened out using a 1mm sieve. After screening, it is transferred to an oven for drying. After drying, the waste rock is separated into 1mm-5mm and larger than 5mm using a 5mm sieve. S204, calculates the mass fraction of waste rock particles at different locations using formulas, and analyzes the deposition of large-diameter and small-sized waste rock at different locations in the simulated mining area and the deposition of waste rock in the mining area under different conditions. S205. After conducting multiple experiments, the uniformity coefficient of tailings-waste gypsum body in narrow stopes under different factors was obtained, and a homogeneity prediction model of tailings-waste gypsum body in narrow stopes was constructed based on the experimental results.

2. The method for predicting the homogeneity of tailings-waste gypsum bodies in narrow mining areas as described in claim 1, characterized in that: The method for conducting basic physical experiments on filling materials includes: S101, conduct physicochemical property tests on the filling material, including moisture content specific gravity, loose bulk density, compacted bulk density, porosity, and particle size distribution; S102, The angle of repose of waste rock particles in the filling material was determined by the bucket lifting method; S103, 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, an orthogonal experiment was designed, and the waste rock accumulation angle under different contact parameters was simulated by discrete element software. S104. The experimental parameters were fitted using Design Expert software to obtain the relationship between the three factors and the packing angle. The measured packing angle of the waste rock was then substituted to obtain the optimal static friction coefficient, dynamic friction coefficient, and recovery coefficient of the waste rock particles.

3. The method for predicting the homogeneity of tailings-waste gypsum bodies in narrow mining areas as described in claim 1, characterized in that: Numerical simulation analysis was used to analyze the spatial distribution of tailings-waste gypsum in a narrow stope and the impact of the location and quantity of the feed inlet on the homogeneity of the slurry. The methods included: S301, Construct a numerical model that matches the actual mine conditions, and perform mesh generation on the numerical model; S302, the tailings slurry is regarded as a continuous phase and the waste rock is regarded as a discrete phase. Fluid parameters and boundary conditions are set in the computational fluid dynamics software, and waste rock parameters are set in the discrete element software. S303 sets up a coupling between the continuous phase and the discrete phase, and sets the governing equations for the interaction between the fluid phase and the discrete phase according to actual needs.

4. The method for predicting the homogeneity of tailings-waste gypsum bodies in narrow mining areas as described in claim 3, characterized in that: Numerical simulation analysis of the spatial distribution of tailings-waste gypsum in narrow stopes and the influence of feed inlet location and quantity on slurry homogeneity also includes: S304. After the simulation, the distribution of waste rock particles in the mining area and the influence of the feed port location on the homogeneity of the tailings-waste gypsum were analyzed using discrete element analysis software. S305. Based on the numerical simulation results, determine the spatial distribution of waste rock particles and the location of the discharge port. Based on the numerical simulation analysis results and the slurry homogeneity prediction model, determine the optimal filling parameters and the location of the discharge port.

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