A method of determining the density of heap leach ore

Abstract

The application discloses a kind of determination methods of heap leaching ore density, it is related to mineral processing and testing and analysis technical field.The ore is accurately matched according to ore type and particle size ratio, natural heap cone is carried out on the rough bottom surface manufactured by cement and ore mixing, and the simulation overburden pressure is applied by hydraulic device for more than 7 days, and the compaction state of heap is reproduced;Subsequently, leaching agent injection cycle is carried out to target element concentration stability, and mass loss caused by mineral dissolution is captured;The upper and lower plane geometric parameters of heap cone after being pressed are measured, the volume is calculated using asymmetric truncated cone volume formula, and uncorrected density is obtained;Finally, combined with the content of easy hydration mineral in automatic mineralogy analysis, the density is corrected by loss rate, and the actual apparent density is obtained.Therefore, the problem that traditional column loading method cannot simulate production compaction and ignores chemical dissolution loss leading to measurement distortion is effectively solved, and the accuracy of heap leaching process parameter calculation is significantly improved.

Description

Technical Field

[0001] This invention relates to the field of mineral processing and testing analysis technology, specifically to a method for determining the density of heap leaching ore, and more specifically to a method for determining the density of mixtures of loose ores in heap leaching processes, particularly applicable to heap leaching sites of copper ores, gold ores containing easily hydrated minerals and multi-granular distribution. Background Technology

[0002] Heap leaching is an important beneficiation and smelting process for treating low-grade copper, gold, and uranium ores, offering advantages such as low investment, low cost, and ease of scaling up. In heap leaching process design, the actual average density of the ore is a crucial fundamental parameter, directly affecting the determination of core process indicators such as heap height, leaching reagent dosage, solution residence time, seepage behavior, and heap stability. However, the ore materials involved in on-site heap leaching operations exhibit high complexity in phase composition, particle size distribution, and stress environment, making it difficult for traditional laboratory density measurement methods to accurately reproduce or adequately reflect the density characteristics under actual heap leaching conditions. Specifically, the challenges are mainly reflected in the following three aspects: First, the mineral composition is complex, containing easily hydrated minerals. Many heap leaching ores contain easily hydrated or soluble minerals such as montmorillonite, chlorite, and kaolinite, which undergo hydration expansion, dispersion, or dissolution during leaching, leading to a reduction in solid phase mass. Traditional density tests (such as the hydrostatic bottle method and the water displacement method) cannot simulate this dynamic loss process, often resulting in overestimation of the density. Second, the particle size distribution is wide. Heap leaching ores range from millimeters to micrometers in size. The bulk density of loosely mixed ores differs significantly from that of single-size or compacted or mixed ores, making it difficult for conventional methods to represent the true packing behavior of such wide-size mixtures. Third, on-site ore heaps exhibit specific geometric shapes and stress states. Actual ore heaps are typically cone-shaped or cone-like, with significant overburden pressure at the bottom. Laboratory methods, however, often employ loose packing or simple compaction, neglecting the influence of cone shape and pressure on density at different depths within the heap.

[0003] In summary, existing density measurement techniques have significant limitations in terms of sample representativeness and stress environment simulation, and the obtained data often deviates considerably from the actual bulk density in the field. This deviation is further amplified in the design of heap leaching for low-grade ores, because low-grade ore bodies typically require larger heap heights and longer leaching cycles, making density errors more sensitive to the overall process economy.

[0004] In view of this, it is necessary to study a method for simulating in-situ heap leaching conditions, including the proportion of ore types, particle size distribution, natural cone morphology, overlying pressure, and the average density of ore lost during circulating leaching, so as to provide more reliable basic data for heap leaching process design. Summary of the Invention

[0005] In view of the technical problems existing in the background art, the present invention provides a method for determining the density of heap leaching ore. Through a combined process of ore blending, screening, natural cone leaching with pressurization, liquid injection circulation, and correction of mineral loss coefficient, the method replaces the standard column with a natural cone morphology, simulates the overburden pressure through hydraulic pressurization, reproduces the chemical disintegration process through liquid injection circulation leaching, and finally uses automatic mineralogical analysis to quantitatively correct the mineral loss, thereby obtaining the theoretical density of ore that is closer to the actual heap leaching process.

[0006] This invention provides a method for determining the density of heap leaching ore, comprising the following steps: S1, Sampling and Blending: Obtain on-site ore samples, prepare mixed samples according to the type and proportion of heap leaching ore, then screen according to the on-site particle size, record the yield of each particle size, and re-blend the mixed samples according to the particle size ratio. S2, Cone Pressurization: The mixed sample is naturally stacked to form an ore cone, which is placed on a bearing base with a rough surface. An overburden pressure simulating the actual heap leaching condition is applied to the ore cone and the pressure is continuously applied until the height of the ore cone changes to a stable value. The height of the ore cone before pressurization is recorded. S3, Liquid Injection and Circulation: Add leaching agent to the ore cone after step S2, so that the leaching liquid circulates in the ore cone to simulate leaching until the leaching system reaches the target element chemical equilibrium state. Record the total mass of the leaching liquid participating in the circulation and the descent height of the ore cone after circulation. S4, Density Calculation: Measure the upper / lower planar dimensions of the ore cone after circulation. Based on the change in the height of the ore cone and the upper / lower planar dimensions, calculate the volume of the ore cone after simulated leaching with natural cone stacking, pressurization, and injection. Based on the mass of the mixed sample, the total mass of the leachate, and the volume, calculate the apparent density of the ore cone. S5, Density Correction: Mineralogical analysis is performed on subsamples of each particle size to determine the content of easily hydrated minerals in each particle size. Based on the yield of each particle size and the content of easily hydrated minerals, a mineral loss correction coefficient is calculated. The apparent density is corrected based on the correction coefficient to obtain the corrected actual apparent density of the ore.

[0007] As a further improvement of the present invention, in step S4, the measurement process of the upper plane dimension and the lower plane dimension includes: measuring the major axis radius r1max and minor axis radius r1min of the contact surface of the upper pressure plate of the ore cone, and measuring the major axis radius r2max and minor axis radius r2min of the contact surface between the lower part of the ore cone and the bearing bottom surface.

[0008] As a further improvement of the present invention, in step S4, the formula for calculating the volume of the ore cone is: V=π×[(r2 max +r2 min ) 2 ×(h1-h2+△h)-(r1 max +r1 min ) 2 [×△h] / 12; Where △h is the height compensation amount; h1 is the initial height of the ore cone; h2 is the descent height of the ore cone after the cycle; r1 max r1 is the radius of the major axis of the contact surface of the pressure plate at the top of the ore cone; min r2 is the minor axis radius of the contact surface of the pressure plate at the top of the ore cone; max r2 is the radius of the major axis of the contact surface between the lower part of the ore cone and the bearing bottom surface; min The minor axis radius is the contact surface between the lower part of the ore cone and the bearing bottom surface.

[0009] As a further improvement of the present invention, the formula for calculating the height compensation amount is as follows: △h=(r1 max +r1 min )×(h1-h2) / (r2 max +r2 min -r1 max -r1 min ).

[0010] As a further improvement of the present invention, in step S5, the formula for calculating the corrected actual apparent density ρ' of the ore is: ρ'=ρ×(1-K), where ρ is the apparent density and K is the mineral loss correction coefficient.

[0011] As a further improvement of the present invention, in step S4, the apparent density ρ is calculated using the formula: ρ=(m1+m2) / V, where m1 is the mass of the mixed sample; m2 is the total mass of the leachate; and V is the volume of the ore cone.

[0012] As a further improvement of the present invention, in step S5, the formula for calculating the mineral loss correction coefficient K is: K=Σ(Ci×ei), where Ci is the yield of the i-th particle size sample; ei is the content of easily hydrated minerals in the i-th particle size.

[0013] As a further improvement of the present invention, in step S2, the bearing bottom surface is made of cement and ore mixed in a volume ratio of 1:(0.1~0.5), and the edge of the bearing bottom surface is provided with anti-diffusion protrusions, which are used to limit the lateral expansion of the pile (ore cone) during the pressurization process. The height of the anti-diffusion protrusion is 0.1 to 0.2 times the initial height of the pile (ore cone), and the extension length of the anti-diffusion protrusion along the edge of the bearing bottom surface is 10 to 15 times the initial height of the pile (ore cone).

[0014] As a further improvement of the present invention, in step S2, the application of the overburden pressure simulating the actual heap leaching condition is achieved by a hydraulic pressurizing device; the lower pressure plate of the hydraulic pressurizing device has a porous structure, and the leachate can enter or exit the heap (ore cone) through the porous structure.

[0015] As a further improvement of the present invention, in step S3, the leachate is added from the top of the ore cone, the liquid flowing out from the bottom of the ore cone is collected, and the collected liquid is added back from the top of the ore cone to form a closed loop, thereby realizing the circulation of the leachate; during the circulation process, the evaporation of the leachate is monitored and the liquid is replenished in a timely manner to maintain a constant total mass of the leachate.

[0016] As a further improvement of the present invention, in step S1, the sieving is carried out according to the following four particle sizes: greater than 30.0 mm, less than or equal to 30.0 mm and greater than 10.0 mm, less than or equal to 10.0 mm and greater than 1.0 mm, and less than or equal to 1.0 mm.

[0017] Beneficial effects: The method provided by this invention is applicable to the density measurement of heap leaching ores such as copper, gold, and uranium, and is particularly suitable for the density determination of low-grade ores containing clay minerals and hydrated minerals. It possesses the following technical advantages: 1. Simulating the on-site heap leaching conditions, this method employs natural cone leaching and pressurization to recreate the morphology of the ore heap under its own weight and external pressure, resulting in a density that more closely approximates actual leaching conditions than traditional loose density methods. Compared to the traditional column loading method, this method comprehensively considers three major factors that cause density deviations: overlying compaction, liquid wetting, and mineral dissolution. The measured apparent density value shows a significantly improved agreement with the in-situ density at the production site.

[0018] 2. Considering the dynamic loss of minerals, the mass of the dissolved solid phase is corrected by weighted summation of the content of easily hydrated minerals in each particle size, so as to avoid underestimation of density or deviation in process calculation due to mineral dissolution.

[0019] 3. The ore is rationally blended by particle size distribution. After screening, it is remixed according to the actual production ratio to avoid representative errors caused by single-size testing. The changes in the radius and height of the upper and lower plane ellipses are considered, along with the changes in the cone shape before and after pressurization, reducing geometric approximation errors. The standardized ore blending process and specific rough bottom surface structure eliminate the influence of human operation differences and container wall effects. The introduction of hydraulic pressurization and liquid injection circulation ensures high comparability and reproducibility of measurement results for different batches and types of ores.

[0020] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it in accordance with the contents of the specification, and in order to make the above and other objects, features and advantages of the present invention more apparent and understandable, specific embodiments of the present invention are described below. Attached Figure Description

[0021] To more clearly illustrate the technical solution of the present invention, the accompanying drawings used in the present invention will be briefly described below. Obviously, the drawings described below are merely some embodiments of the present invention, and those skilled in the art can obtain other drawings based on these drawings without any creative effort.

[0022] Figure 1 This is a schematic flowchart of the method for determining the density of heap leaching ore provided in an embodiment of the present invention. Detailed Implementation

[0023] The embodiments of the technical solution of the present invention will now be described in detail with reference to the accompanying drawings. These embodiments are merely illustrative of the technical solution of the present invention and are therefore intended to limit the scope of protection of the present invention.

[0024] 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 invention pertains; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the invention; the terms “comprising” and “having”, and any variations thereof, in the specification, claims, and foregoing description of the invention, are intended to cover non-exclusive inclusion.

[0025] In the description of the embodiments of this invention, technical terms such as "first" and "second" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this invention, "multiple" means two or more, unless otherwise explicitly defined.

[0026] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of the invention. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0027] In the description of the embodiments of this invention, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this document generally indicates that the preceding and following related objects have an "or" relationship.

[0028] To address the severe decoupling between the traditional static, instantaneous, and homogeneous density measurement system in the laboratory and the dynamic, time-varying, and heterogeneous heap leaching environment in existing low-grade ore heap leaching process designs, which leads to systematic distortion of basic physical property parameters (density), and consequently causes a series of technical problems such as inaccurate design benchmarks, deviations from expected leaching efficiency, and loss of control over engineering safety redundancy, this invention provides a method for determining the density of heap leaching ore. A free cone model with a rough bottom is constructed, and continuous pressurization for ≥7 days using a hydraulic device accurately simulates the overburden pressure of deep ore heaps (ore cones). This ensures that the ore density measured in the laboratory significantly approximates the actual production conditions, overcoming the technical shortcomings of traditional methods that loosely pack ore in smooth-walled containers, completely ignoring the compaction effect of the ore under its own weight and the wetting effect of the leachate in actual production. Furthermore, a liquid injection and circulation process is introduced, quantifying the content of easily hydrated minerals in each particle size by monitoring the consumption of leaching agent and combining it with automated mineralogical analysis. By modifying the formula to deduct the mass lost due to dissolution in density calculations, an effective apparent density that truly reflects the physical properties of the ore skeleton is obtained. This overcomes the technical shortcomings of traditional density measurements, which are all dry or static measurements assuming a constant ore mass. However, in actual heap leaching, easily hydrated gangue continuously dissolves and is lost, leading to a reduction in the mass of the heap skeleton and an artificial increase in porosity. This invention eliminates the wall effect through a rough boundary anti-diffusion design, uses an asymmetric truncated cone volume formula to calculate complex heap geometry, and finally uses process mineralogical data for macroscopic physical parameter correction. This fills the technical gap that traditional heap density measurements cannot reflect dynamic losses and compaction effects, significantly improving the accuracy of heap leaching volume calculations.

[0029] Please refer to Figure 1 As shown, this invention provides a method for determining the density of heap leaching ore. It measures the apparent density of heap leaching ore during production, and through a combined process of ore blending, screening, natural cone leaching with pressurization, liquid injection circulation, and correction of the mineral loss coefficient, obtains the theoretical density of the ore that more closely approximates the actual heap leaching process. Specifically, it includes the following steps: S1, Sampling and ore blending S11, ore type blending Take on-site samples and mix the ore according to the type and proportion of ore for heap leaching. Specifically, divide the ore into different types A, and take samples of Aa kg, where A is the quantity of ore type and a is the mass of ore type A. Prepare mixed samples according to the actual proportion of selected samples.

[0030] S12, sieved particle size distribution Based on the particle size characteristics of the ore at the site, the above-mentioned mixed sample was sieved according to particle size i (i is 1, 2, 3, 4, representing the particle size range of four particle sizes: greater than 30.0 mm, less than or equal to 30.0 mm and greater than 10.0 mm, less than or equal to 10.0 mm and greater than 1.0 mm, and less than or equal to 1.0 mm, respectively), to obtain sample Bi, which was weighed and recorded as bi g. Then, the yield of each particle size Ci = bi / ∑bi; Mix sample D according to the actual on-site ore particle size characteristics, weigh it, and record it as m1 kg, where m1 is 200~500.

[0031] S2, natural cone formation and pressurization S21, take the mixed sample D from step S1, and naturally stack a cone (with a rough bottom surface, cement: ore = 1: (0.1~0.5) volume ratio, mixed and manufactured) to obtain an ore cone, and record the initial cone height h1 m.

[0032] The height of the anti-diffusion protrusion is 0.1 to 0.2 times the initial height of the ore cone, and the extension length of the anti-diffusion protrusion along the edge of the bearing bottom surface is 10 to 15 times the initial height of the ore cone. That is, in order to prevent the endless diffusion of the ore sample, the anti-diffusion protrusion is in the shape of a ring with a diameter of (10 to 15) × h1 m.

[0033] S22, calculate or measure the overburden pressure of the ore cone (specifically measure the density characteristics at different depths), and pressurize this pressure using a pressurizing device until it stabilizes (continuous pressurization, constant cone height, maintained for 7 days or more).

[0034] The pressurizing device is preferably a hydraulic device, with a porous flat plate at the bottom and a rough surface.

[0035] S3, Injection Circulation Add leaching reagent (such as dilute sulfuric acid for copper ore), and perform a cyclic leaching operation (add liquid at the top, collect at the bottom, then add more from the top, controlling the total liquid volume, and replenishing liquid promptly during evaporation) until the target element concentration stabilizes. Weigh the liquid used (excluding the evaporated liquid) and record it as m² kg. Record the descent height of the pressure plate as h² m, which is the descent height of the ore cone after circulation.

[0036] The liquid used is a solution for reacting with the target element. The liquid is then recovered, and the target element is extracted from it. Different target elements require different liquids; for example, sodium cyanide liquid is used for gold.

[0037] S4, Parameter Measurement and Density Calculation Measure the parameters of the ore surface at the pressure plate, i.e., the major axis radius r1 of the upper plane of the heap leaching ore. max m, minor axis radius r1 min m; Measure the parameters of the ore surface at the bottom of the heap cone, i.e., the major axis radius r2 of the lower plane of the heap leaching ore. max m, minor axis radius r2 min m.

[0038] Calculate the height compensation amount △h=(r1) max +r1 min )×(h1-h2) / (r2 max +r2 min -r1 max -r1 min ); The volume V of the ore cone is calculated using the following formula: V=π×[(r2 max +r2 min ) 2 ×(h1-h2+△h)-(r1 max +r1 min ) 2 [×△h] / 12; Then the apparent density ρ = (m1 + m2) / V.

[0039] S5, Data Correction The sample Bi from step S12 is finely ground and then subjected to automated mineralogical analysis. The contents of easily hydrated minerals are measured to be ei. The loss rate of dissolved minerals in the ore, i.e. the mineral loss correction coefficient, is K, K=ΣCi×ei.

[0040] The actual apparent density of the ore is ρ' = ρ × (1 - K).

[0041] The content of easily hydrated minerals refers to the total content of minerals that are easily soluble in leaching agents.

[0042] The fine grinding is carried out using dry grinding methods, such as rod mills and jar mills.

[0043] No water is added during the entire sample preparation and polishing process. Oily substances are preferred, such as OS type, MP-Y, K type lubricants, paraffin oil, etc.

[0044] The sample preparation process is as follows: the finely ground sample is placed in a grinding mold and mixed with an epoxy resin mixture (epoxy resin and its corresponding curing agent, volume ratio 1.0:(0.2~1.0)), with the height controlled at 1.0~1.5 cm. The sample is then subjected to ultrasonic vibration for 10.0~20.0 min to remove air bubbles, and then placed in a constant temperature environment of 45~65℃ to accelerate curing. The bottom surface of the inlaid sample is then subjected to coarse grinding, fine grinding, and polishing (polishing uses 1~0.5 micrometer abrasive) to create a flat and smooth initial measurement surface, and then carbonized to 10~20 nm.

[0045] Example 1 Embodiment 1 of the present invention provides a method for determining the density of heap leaching ore, specifically applied to the density determination of a sample of copper ore after it has been heaped, and includes the following steps: S1, Sampling and ore blending S11, a copper mine heap leaching process has two types of ore: copper oxide (A1) and copper sulfide (A2). The ore is mixed according to the production ratio of oxide ore: sulfide ore = 6.23: 3.77.

[0046] Take 311.5 kg of oxide ore and 188.5 kg of sulfide ore, mix them to obtain sample Aa = 500 kg.

[0047] S12, blend the above samples according to the four particle size characteristics of the ore on site: i=1 (particle size > 30.0 mm); b1=48.52%; i=2 (30.0 ≥ particle size > 10.0 mm); b2=27.35%; i=3 (10.0 ≥ particle size > 1.0 mm); b3=14.28%; i=4 (particle size ≤ 1.0 mm); b4=9.85%.

[0048] The yields of the ore particle size characteristics at the site were 48.52%, 27.35%, 14.28%, and 9.85%, respectively. A new mixed sample D was prepared based on these yields, with a total mass m1 = 300 kg.

[0049] S2, naturally conical and pressurized, the initial height after natural conical formation is h1=0.86 m. A porous pressure plate is used to pressurize until stable (pressure is 0.56 MPa, calculated value).

[0050] The natural cone-shaped ore pile is formed by mixing ores of different particle sizes according to the aforementioned particle size ratio and slowly pouring the mixture from a lower position to create an approximately conical ore pile. The bottom surface of the cone is rough. During the pressurization process, the pressure value can be calculated based on depth and measured on-site at the actual depth.

[0051] S3, leaching and circulation: Add a 5.0% (w / w) dilute sulfuric acid solution and leach for 8 days until the Cu²⁺ concentration in the leachate stabilizes (with two consecutive changes ≤0.05 g / L). Total mass of leachate added: m² = 175.12 kg. The height of the pressure plate drop after circulation (the height of the ore cone drop after circulation): h² = 0.13 m.

[0052] S4, Parameter Measurement and Density Calculation Upper surface of the pressure plate: r1max = 0.93 m, r1min = 0.75 m; Lower plane of the ore pile: r2max = 1.17 m, r2min = 1.04 m; △h=(r1 max +r1 min )×(h1-h2) / (r2 max +r2 min -r1 max -r1 min = 2.314 m; The volume V of the cone is calculated using the following formula: V=π×[(r2 max +r2 min ) 2 ×(h1-h2+△h)-(r1 max +r1 min ) 2 [×△h] / 12=2.1817 m 3 ; Apparent density: ρ = (300 + 175.12) / 2.1817 ≈ 217.78 kg / m³ 3 .

[0053] S5, mineral loss correction: After fine grinding (less than 0.074 mm) of each particle size, automated mineralogical analysis was performed to determine the content of easily hydrated minerals (combined content of copper minerals, montmorillonite, and chlorite minerals): e1 = 2.13%; e2=3.43%; e3 = 5.20%; e4 = 8.75%; The solubility coefficient K is then 0.4852×2.13%+0.2735×3.43%+0.1428×5.20%+0.0985×8.75%=3.576%.

[0054] Therefore, the actual theoretical density is: ρ′=217.78×(1-0.03576)≈209.99 kg / m³ 3 .

[0055] The above indicates that the actual theoretical density of the copper ore mixture under heap leaching conditions is 209.99 kg / m³, which can be directly used for subsequent heap height design, leaching agent dosage calculation and solution flow simulation. This density is more consistent with the actual leaching process than the apparent density without correction (217.78 kg / m³).

[0056] In summary, this invention discloses a method for determining the density of heap leaching ore, relating to the field of mineral processing and testing analysis technology. By precisely blending ore according to type and particle size ratio, a natural cone is formed on a rough bottom surface constructed from a cement-ore mixture. A simulated overburden pressure is applied using a hydraulic device and maintained stably for more than 7 days to reproduce the compacted state of the ore pile. Subsequently, the leaching agent is injected and circulated until the target element concentration stabilizes, capturing the mass loss caused by mineral dissolution. The geometric parameters of the upper and lower planes of the cone after compression are measured, and the volume is calculated using the asymmetric truncated cone volume formula to obtain the uncorrected density. Finally, the density is corrected by the loss rate based on the content of easily hydrated minerals obtained from automated mineralogical analysis to obtain the actual apparent density. This effectively solves the problems of traditional column-packing methods failing to simulate production compaction and ignoring chemical dissolution losses, leading to measurement distortion, and significantly improves the accuracy of heap leaching process parameter calculations.

[0057] It should be noted that the present invention is not limited to the above-described embodiments. The above embodiments are merely examples, and any embodiments that have the same structure and perform the same effects as the technical concept within the scope of the present invention are included within the scope of the present invention. Furthermore, various modifications that can be conceived by those skilled in the art to the embodiments, and other ways of constructing by combining some of the constituent elements of the embodiments, without departing from the spirit of the present invention, are also included within the scope of the present invention.

Claims

1. A method for determining the density of heap leaching ore, characterized in that, The steps include the following: S1, Sampling and Blending: Obtain on-site ore samples, prepare mixed samples according to the type and proportion of heap leaching ore, then screen according to the on-site particle size, record the yield of each particle size, and re-blend the mixed samples according to the particle size ratio. S2, Cone Pressurization: The mixed sample is naturally stacked to form an ore cone, which is placed on a bearing base with a rough surface. An overburden pressure simulating the actual heap leaching condition is applied to the ore cone and the pressure is continuously applied until the height of the ore cone changes to a stable value. The height of the ore cone before pressurization is recorded. S3, Liquid Injection and Circulation: Add leaching agent to the ore cone after step S2, so that the leaching liquid circulates in the ore cone to simulate leaching until the leaching system reaches the target element chemical equilibrium state. Record the total mass of the leaching liquid participating in the circulation and the descent height of the ore cone after circulation. S4, Density Calculation: Measure the upper / lower planar dimensions of the ore cone after circulation. Based on the change in the height of the ore cone and the upper / lower planar dimensions, calculate the volume of the ore cone after simulated leaching with natural cone stacking, pressurization, and injection. Based on the mass of the mixed sample, the total mass of the leachate, and the volume, calculate the apparent density of the ore cone. S5, Density Correction: Mineralogical analysis is performed on subsamples of each particle size to determine the content of easily hydrated minerals in each particle size. Based on the yield of each particle size and the content of easily hydrated minerals, a mineral loss correction coefficient is calculated. The apparent density is corrected based on the correction coefficient to obtain the corrected actual apparent density of the ore. In step S4, the formula for calculating the volume of the ore cone is: V=π×[(r2 max +r2 min ) 2 ×(h1-h2+△h)-(r1 max +r1 min ) 2 ×△h] / 12; Where △h is the height compensation amount; h1 is the initial height of the ore cone; h2 is the descent height of the ore cone after the cycle; r1 max r1 is the radius of the major axis of the contact surface of the pressure plate at the top of the ore cone; min r2 is the minor axis radius of the contact surface of the pressure plate at the top of the ore cone; max r2 is the radius of the major axis of the contact surface between the lower part of the ore cone and the bearing bottom surface; min The minor axis radius of the contact surface between the lower part of the ore cone and the bearing bottom surface; The formula for calculating the height compensation amount is: △h=(r1 max +r1 min )×(h1-h2) / (r2 max +r2 min -r1 max -r1 min ); In step S4, the apparent density ρ is calculated using the formula: ρ = (m1 + m2) / V, where m1 is the mass of the mixed sample; m2 is the total mass of the leachate; and V is the volume of the ore cone. In step S5, the formula for calculating the corrected actual apparent density ρ' of the ore is: ρ'=ρ×(1-K), where ρ is the apparent density and K is the mineral loss correction coefficient; In step S5, the formula for calculating the mineral loss correction coefficient K is: K=Σ(Ci×ei), where Ci is the yield of the i-th particle size sample; ei is the content of easily hydrated minerals in the i-th particle size.

2. The method for determining the density of heap leaching ore according to claim 1, characterized in that, In step S2, the bearing bottom surface is made of cement and ore mixed in a volume ratio of 1:(0.1~0.5). The edge of the bearing bottom surface is provided with anti-diffusion protrusions, which are used to limit the lateral expansion of the ore cone during the pressurization process. The height of the anti-diffusion protrusion is 0.1 to 0.2 times the initial height of the ore cone, and the extension length of the anti-diffusion protrusion along the edge of the bearing bottom surface is 10 to 15 times the initial height of the ore cone.

3. The method for determining the density of heap leaching ore according to claim 1, characterized in that, In step S2, the application of the overburden pressure simulating the actual heap leaching conditions is achieved through a hydraulic pressurizing device; the lower pressure plate of the hydraulic pressurizing device has a porous structure, through which the leachate can enter or exit the ore cone.

4. The method for determining the density of heap leaching ore according to claim 1, characterized in that, In step S3, the leachate is added from the top of the ore cone, the liquid flowing out from the bottom of the ore cone is collected, and the collected liquid is added back from the top of the ore cone to form a closed loop, thereby realizing the circulation of the leachate. During the circulation process, the evaporation rate of the leachate is monitored and liquid is replenished in a timely manner to maintain a constant total mass of the leachate.

5. The method for determining the density of heap leached ore according to claim 1, characterized in that, In step S1, the sieving is carried out according to the following four particle sizes: greater than 30.0 mm, less than or equal to 30.0 mm and greater than 10.0 mm, less than or equal to 10.0 mm and greater than 1.0 mm, and less than or equal to 1.0 mm.

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