Experimental method for evaluating dissolution mining effect of solid trona ore

Abstract

The invention discloses a solid trona ore solution mining effect evaluation experiment method, and relates to the technical field of salt mineral exploitation, and the method comprises the following steps: obtaining a physical simulation experiment device, and preparing a required alkali ore sample according to a sample specification required by a dissolution unit in the physical simulation experiment device; calculating and determining the water quantity V model required by the simulation experiment, and further preparing a solvent; filling the model with the prepared solvent, and performing a dissolution experiment to obtain dissolution experiment data; and analyzing the dissolution experiment data, and performing effect evaluation on an analysis result. According to the method, more reliable parameters are provided for development scheme compilation of the alkali mine and ground matching engineering construction planning, and meanwhile, the quality of the alkali mine can be preliminarily judged.

Description

Technical Field

[0001] This application belongs to the field of salt mineral development technology, and in particular relates to an experimental method for evaluating the leaching and mining effect of solid natural alkali ore. Background Technology

[0002] Natural alkali, in mineralogy, refers to minerals such as sodium carbonate and sodium bicarbonate. In industrial mineralogy and petrology, it refers to sodium carbonate, bicarbonate, and hydrous carbonate minerals from which sodium carbonate components can be extracted; it is an important raw material for the alkali production industry. Ancient solid natural alkali deposits were buried deep underground and generally mined using a water-dissolution method. Water or a specially formulated solvent was injected into the underground solid natural alkali deposit to dissolve the natural alkali, obtaining an alkaline brine solution mainly composed of sodium carbonate and sodium bicarbonate, which was then returned to the surface for processing. However, the dissolution process of natural alkali is greatly affected by the type of natural alkali, the solution temperature, and the solvent formulation. Dissolution experiments need to be conducted before alkali mining to understand the characteristics of the dissolution process in detail, and this information is used as the basis for developing development plans and planning the construction of supporting surface infrastructure.

[0003] There are few existing articles, patents, and standards concerning laboratory experiments on the water solubility parameters of natural alkalis. Appendix C of the geological and mineral industry standard DZ / T0212.3-2020 "Specifications for Mineral Geological Exploration - Salts Part 3: Ancient Solid Salts" issued by the Ministry of Natural Resources of the People's Republic of China describes the laboratory experimental methods and requirements for the water solubility properties of ancient solid salt ores. This method has the following characteristics: ① The solvent is tap water or neutral water; ② The temperature is room temperature; ③ The test is conducted in still water; ④ The core sample is at least 20cm long and is a complete ore core, and the test is conducted by suspending the sample in a dissolution pool; ⑤ The dissolution device is a large beaker or a dissolution pool; ⑥ The alkali ore sample needs to be coated with a 1:1 mixture of paraffin and bitumen boiling solution; ⑦ The amount of water used for dissolution is the expected amount of water saturated with brine at room temperature; ⑧ The dissolution rate is expressed as the average advance of dissolution erosion on the dissolution surface. However, in actual development, the dissolution conditions for natural alkali ore are: ① Water is not used as a solvent, but a low-concentration alkali solution is used; ② To improve dissolution efficiency, the solvent temperature is >50℃; ③ The solvent is not static, but continuously circulating; ④ Some alkali ore layers are thin-layered, less than 20cm thick, or to improve dissolution efficiency, thick ore layers are fractured, crushed, and modified. In these cases, it is impossible to obtain a 20cm long complete ore core. In addition, existing experimental methods have some shortcomings, including: ⑤ The simple dissolution apparatus used leads to water evaporation during the experiment, thus affecting the brine concentration; ⑥ The high-temperature mixture of paraffin and bitumen causes changes in ore composition; ⑦ The calculation of dissolved water volume does not take into account the characteristics of on-site dissolution and mining; ⑧ The data on dissolution rate is insufficient for on-site application guidance, and data on the alkali content, harmful component content, and optimal dissolution time in the brine are more needed on-site. These shortcomings prevent existing experimental methods from effectively simulating the development process, and the obtained dissolution parameters cannot effectively guide the development plan and the planning of ground supporting engineering construction. Summary of the Invention

[0004] The embodiments of this application provide an experimental method for evaluating the leaching and mining effect of solid natural soda ash ore, solving three technical problems in the existing technical solutions.

[0005] Other features and advantages of this application will become apparent from the following detailed description, or may be learned in part from practice of this application.

[0006] According to an embodiment of this application, an experimental method for evaluating the leaching and mining effect of solid natural soda ash ore is provided, including the following steps:

[0007] Step (1): Obtain the physical simulation experimental device and prepare the required alkali ore sample according to the sample specifications required by the dissolution unit in the physical simulation experimental device;

[0008] Step (2): Calculate and determine the amount of water V required for the simulation experiment. 模 Then, the solvent is prepared;

[0009] Step (3): Fill the model with the prepared solvent and conduct a dissolution experiment to obtain dissolution experiment data;

[0010] Step (4): Analyze the dissolution experiment data and evaluate the effectiveness of the analysis results.

[0011] Furthermore, the physical simulation experimental device includes a temperature control unit, a dissolution experimental unit, a water circulation unit, a water storage unit, a parameter measurement unit, and a brine sampling unit.

[0012] Further, in step (1), the sample specifications required by the dissolution unit in the physical simulation experimental device are as follows: select a soda ash ore section with a thickness greater than 10cm, wherein the soda ash ore section includes no inclusions and no muddy layers, select a rock core cut perpendicular to the rock layer direction to form a rock sheet with a thickness of 3-5cm and the same length.

[0013] Furthermore, the preparation of the solvent in step (2) includes the following steps:

[0014] Step (2.1): Determine the solvent formulation, solvent temperature T, and solvent concentration in the solvent extraction scheme;

[0015] Step (2.2): Calculate the amount of solvent and weigh the solvent according to the amount of solvent;

[0016] Step (2.3): Take water using well site water source, distilled water or deionized water;

[0017] Step (2.4): Heat water to temperature T, slowly add solvent, stir with a glass rod to dissolve, and obtain the prepared solution;

[0018] Step (2.5): After preparation, seal the container and store it in a constant temperature incubator for later use.

[0019] Furthermore, the step (3) of filling the model with the prepared solvent includes the following steps:

[0020] Step (3.1): In non-fracturing mining, crystal glue is used to bond rock flakes to form annular alkali ore bodies; while in fracturing mining, support particles are laid on the fracture surface and the fragmented rock flakes are bonded together to form annular, fragmented alkali ore bodies.

[0021] Step (3.2): Turn on the model's temperature control unit to preheat the model and set the constant temperature to T;

[0022] Step (3.3): Fill the water storage unit with solvent;

[0023] Step (3.4): After the model temperature is kept constant for 15 minutes, the density of the brine is measured as g0 and the percentage of sodium carbonate is A0, and then the model is filled.

[0024] Furthermore, the dissolution experiment in step (3) includes the following steps:

[0025] Step (3.5): Turn on the water supply pipeline pump and fill the dissolving chamber with solvent. The time at this time is recorded as t0.

[0026] Step (3.6): Adjust the flow rate of the water supply pump and the return pump to keep the liquid level in the dissolution chamber completely submerging the upper edge of the dissolution window of each rock fragment, and obtain the complete dissolution simulation experiment process;

[0027] Step (3.7): In the dissolution simulation experiment, record parameters and take brine samples;

[0028] Step (3.8): After 24 hours of the experiment, the dissolution experiment is ended.

[0029] Furthermore, the analysis of the dissolution experiment data in step (4) includes: determining the dissolution effect at different time points by drawing a diagram of the change in brine density, a diagram of the change in the percentage content of sodium carbonate in brine, and a diagram of the change in the percentage content of sodium chloride in brine.

[0030] Furthermore, the chart showing the change in brine density is a graph with time as the horizontal axis and density as the vertical axis; the chart showing the change in the percentage of sodium carbonate content in brine is a graph with time as the horizontal axis and sodium carbonate content as the vertical axis; and the chart showing the change in the percentage of sodium chloride content in brine is a graph with time as the horizontal axis and sodium chloride content as the vertical axis.

[0031] Furthermore, in step (4), the analysis results are evaluated, including determining the optimal dissolution time and preliminarily evaluating the quality of the ore layer by the percentage content of sodium chloride.

[0032] This invention provides an experimental method for realistically simulating the water-soluble mining process of solid natural alkali ore, with the following characteristics: ① Dissolution experiments can be conducted using specific solvent formulations required by the development plan; ② The temperature of the entire experimental simulation process is adjustable, ranging from room temperature to 100℃; ③ The solvent flow characteristics can be simulated during the experiment; ④ The characteristics of thin-layered alkali ore and fractured alkali ore layers can be simulated; ⑤ The entire experimental process is closed to avoid the influence of water evaporation; ⑥ Low-temperature crystal glue is used to avoid changes in the composition of the alkali ore; ⑦ A reasonable method for calculating the dissolved water volume is established considering the characteristics of on-site dissolution and mining and the characteristics of the experimental model; ⑧ During the experiment, parameters such as solution density, alkali content, and sodium chloride content at different time points can be obtained as needed, and the optimal dissolution time can be evaluated. This provides more reliable parameters for the preparation of alkali ore development plans and the planning of ground-based supporting engineering construction.

[0033] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and do not limit this application. Attached Figure Description

[0034] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application. It is obvious that the drawings described below are merely some embodiments of this application, and those skilled in the art can obtain other drawings based on these drawings without any inventive effort. In the drawings:

[0035] Figure 1 A schematic diagram of a physical simulation experimental device for single-well karst mining in a solid natural soda ash ore karst mining effect evaluation experimental method described in one embodiment is shown.

[0036] Figure 2 A schematic diagram of the dissolution radius in an experimental method for evaluating the dissolution and mining effect of solid natural soda ore as described in one embodiment is shown, wherein Figure (a) is a schematic diagram of the first dissolution radius and Figure (b) is a schematic diagram of the second dissolution radius;

[0037] Figure 3 (a) shows the crystal glue sealing of rock fragments under non-fracturing conditions in an experimental method for evaluating the karst mining effect of solid natural alkali ore as described in one embodiment; (b) shows the fracturing simulation under fracturing conditions in an experimental method for evaluating the karst mining effect of solid natural alkali ore as described in one embodiment.

[0038] Figure 4 This figure shows the brine density variation in a single-well vertical well during a simulated leaching and mining experiment method for evaluating the leaching and mining effect of solid natural soda ash ore, as described in one embodiment.

[0039] Figure 5 This figure shows the change in sodium carbonate percentage in simulated brine during single-well vertical well leaching and mining in an experimental method for evaluating the leaching and mining effect of solid natural soda ash ore as described in one embodiment.

[0040] Figure 6 This figure shows the change in the percentage of sodium chloride in simulated brine during single-well vertical well leaching and mining in an experimental method for evaluating the leaching and mining effect of solid natural soda ash ore as described in one embodiment.

[0041] Figure 7 This figure shows the brine density variation in a single-well vertical shaft fracturing and leaching process, as described in an embodiment of an experimental method for evaluating the leaching and mining effect of solid natural soda ash ore.

[0042] Figure 8This figure shows the change in sodium carbonate percentage in simulated brine during single-well vertical well fracturing and leaching extraction, as described in an experimental method for evaluating the leaching and extraction effect of solid natural soda ash ore in one embodiment.

[0043] Figure 9 The diagram illustrates the change in the percentage of sodium chloride in simulated brine during single-well vertical well fracturing and leaching extraction, as described in an embodiment of an experimental method for evaluating the leaching and extraction effect of solid natural alkali ore.

[0044] The markings in the diagram are: 1. Temperature control unit; 6. Brine sampling unit; 4. Water storage unit; 5. Digital liquid density meter; 21. Dissolving chamber; 22. Dissolving chamber cover; 31. Water supply pipeline; 32. Water return pipeline. Detailed Implementation

[0045] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0046] Furthermore, the described features, structures, or characteristics can be combined in any suitable manner in one or more embodiments. Numerous specific details are provided in the following description to give a thorough understanding of embodiments of this application. However, those skilled in the art will recognize that the technical solutions of this application can be practiced without one or more of the specific details, or other methods, components, apparatuses, steps, etc., can be employed. In other instances, well-known methods, apparatuses, implementations, or operations are not shown or described in detail to avoid obscuring various aspects of this application.

[0047] The block diagrams shown in the accompanying drawings are merely functional entities and do not necessarily correspond to physically independent entities. That is, these functional entities can be implemented in software, in one or more hardware modules or integrated circuits, or in different network and / or processor devices and / or microcontroller devices.

[0048] The flowcharts shown in the accompanying drawings are merely illustrative and do not necessarily include all content and operations / steps, nor do they necessarily have to be performed in the described order. For example, some operations / steps can be broken down, while others can be combined or partially combined; therefore, the actual execution order may change depending on the specific circumstances.

[0049] This invention provides an experimental method for evaluating the dissolution and mining effects of solid natural alkali ore, overcoming the shortcomings of existing alkali ore dissolution experimental techniques and achieving the invention's objective. It has the following eight features: ① Dissolution experiments can be conducted using specific solvent formulations required by the development plan; ② The temperature of the entire experimental simulation process is adjustable, ranging from room temperature to 100℃; ③ The experiment can simulate solvent flow characteristics; ④ It can simulate the characteristics of thin-layered alkali ore and fractured alkali ore layers; ⑤ The entire experimental process is closed, avoiding the influence of water evaporation; ⑥ Low-temperature crystal glue is used to avoid changes in alkali ore composition; ⑦ A reasonable method for calculating dissolved water volume is established considering both on-site dissolution and mining characteristics and experimental model characteristics; ⑧ During the experiment, parameters such as solution density, alkali content, and sodium chloride content at different time points can be obtained as needed, and the optimal dissolution time can be evaluated. This provides more reliable parameters for development plan preparation and ground-based supporting engineering construction planning. Simultaneously, it can also provide a preliminary assessment of the alkali ore quality.

[0050] Specifically, an experimental method for evaluating the leaching and mining effect of solid natural soda ash ore includes the following steps:

[0051] Step (1): Obtain the physical simulation experimental device and prepare the required alkali ore sample according to the sample specifications required by the dissolution unit in the physical simulation experimental device;

[0052] Step (2): Calculate and determine the amount of water V required for the simulation experiment. 模 Then, the solvent is prepared;

[0053] Step (3): Fill the model with the prepared solvent and conduct a dissolution experiment to obtain dissolution experiment data;

[0054] Step (4): Analyze the dissolution experiment data and evaluate the effectiveness of the analysis results.

[0055] Specifically, in step (1), the sample specifications required by the dissolution unit in the physical simulation experimental device are as follows: select a soda ash ore section with a thickness greater than 10cm, wherein the soda ash ore section includes no inclusions and no muddy laminae, select a rock core cut perpendicular to the rock layer direction to form a rock sheet with a thickness of 3-5cm and the same length.

[0056] It should be noted that, based on the sample specifications required by the dissolution unit in the physical simulation experimental setup, appropriate mineral cores are selected for processing, including:

[0057] ① Selection of core sections. Select soda ash ore sections with a thickness greater than 10cm, free of inclusions and argillaceous laminae; for thin interbedded ore layers, calculate the cumulative thickness of the soda ash layer, and a cumulative thickness greater than 10cm is acceptable;

[0058] ② Cut the rock core along the direction perpendicular to the rock strata to form rock slices with a thickness of 3-5cm and the same length; the length of the rock slices is determined according to the size of the dissolution chamber; the number of rock slices needs to be determined according to the perimeter of the dissolution chamber; clean the rock slices with a brush and place them in a desiccator for later use;

[0059] ③ For non-fracturing mining, it is necessary to determine the location of the dissolution window for each rock fragment, and seal the part outside the dissolution window with crystal glue. The length of the window is h (unit, m).

[0060] For fracturing operations, crystal sealant is not required. Instead, the rock fragments should be carefully broken into irregular fractures, with each fragment having 3-6 fractures. The fragments should then be carefully placed in a desiccator for later use. The total sample length is h (in meters).

[0061] Specifically, the dissolution experiment in step (3) includes the following steps:

[0062] Step (3.5): Turn on the water supply pipeline pump and fill the dissolving chamber with solvent. The time at this time is recorded as t0.

[0063] Step (3.6): Adjust the flow rate of the water supply pump and the return pump to keep the liquid level in the dissolution chamber completely submerging the upper edge of the dissolution window of each rock fragment, and obtain the complete dissolution simulation experiment process;

[0064] Step (3.7): In the dissolution simulation experiment, record parameters and take brine samples;

[0065] Step (3.8): After 24 hours of the experiment, the dissolution experiment is ended.

[0066] The parameter recording and brine sampling include: recording the brine density value every 10 minutes within 1 hour and taking a 5ml brine sample through the brine sampling unit; recording the brine density value every hour after 1 hour and taking a 5ml brine sample through the brine sampling unit; the brine needs to be tested for the percentage content of sodium carbonate and sodium chloride.

[0067] Specifically, in this embodiment, the following describes in detail the experimental method for evaluating the leaching effect of solid natural alkali mines, taking the physical simulation process of leaching mining in a certain mine in a solid natural alkali mine block as an example.

[0068] In summary, this invention achieves efficient dissolution of alkali ore samples through a physical simulation experimental apparatus combined with precise water volume calculation formulas and solvent preparation steps. It particularly emphasizes the synergistic effect of temperature control, water circulation, and parameter measurement to ensure the stability and controllability of the dissolution process. By systematically recording and analyzing the changes in brine density, sodium carbonate, and sodium chloride percentages over time, this invention can accurately assess the dissolution effect at different time points, thus providing a scientific basis for determining the optimal dissolution time and evaluating ore layer quality. Furthermore, this invention provides detailed experimental procedures and data analysis methods, offering a novel technical approach for the efficient and environmentally friendly mining of solid natural alkali ore.

[0069] It should be noted that in some relevant embodiments, the alkali ore layer in this mine is buried at a depth of 1710m-1747m. The main alkali ore component is natural alkali (Na2CO3·NaHCO3·2H2O), with a small amount of sodium hydroxide (Na2CO3·3NaHCO3), all in solid form. The industrial ore layer thickness is 25.8m. The lithology of the top and bottom plates of the ore layer is mainly mudstone, silty mudstone, and carbonate mudstone, interbedded with thin layers of argillaceous dolomite. The interbedded rocks in the natural alkali ore layer are mainly evaporite mudstone, evaporite silty mudstone, and evaporite silty mudstone; they are mostly dark gray or grayish-black, with a argillaceous structure and layered texture; the rock inclusion rate is 30.23%. A 3% sodium carbonate solution at 80℃ is proposed to be used as the solvent. Simulation experiments are needed to determine the optimal dissolution time under different mining methods, providing data support for the development of surface treatment facilities.

[0070] In some embodiments, the karst mining effect of the ore layer was evaluated using the technical solution described in this invention, and the effect was significant. The steps for the single-well vertical shaft karst mining effect evaluation experiment are as follows:

[0071] Step 1: Obtain the physical simulation experimental setup

[0072] The physical simulation experimental device should include six modular units: a temperature control unit, a dissolution experiment unit, a water circulation unit, a water storage unit, a parameter measurement unit, and a brine sampling unit. (Some components may be listed here.) Figure 1 As shown.

[0073] Step 2: Sample preparation of alkali ore

[0074] ① Selection of core sections. The thickness of a single layer of soda ash ore in this ore layer is mostly 10-30cm. Therefore, a soda ash ore section with a thickness of about 15cm was selected, without interbedded stones or argillaceous laminations.

[0075] ② Cut the rock core along the direction perpendicular to the rock strata to form a rock slice with a thickness of 5cm; the rock slice is 0.15m long and about 8cm wide; there are 8 rock slices in total (the perimeter of the dissolution test unit is 62.8cm); clean the rock slices with a brush and place them in a desiccator for later use;

[0076] ③ The dissolution window is 10cm long. Seal the part outside the dissolution window with crystal glue.

[0077] Step 3: Calculate and determine the amount of water V required for the simulation experiment. 模

[0078] ①The actual dissolution radius R of the production well ore layer is taken as 0.5m, and the model dissolution radius r is taken as 0.1m, such as Figure 2 As shown in (a) and (b) in the figure.

[0079] ② Calculate V according to formula (1) 模 It is 0.0157m 3 That is, 15.7 liters.

[0080] Step 4: Prepare the solvent

[0081] ① The solvent formulation in the solvent extraction scheme is specified as sodium carbonate solution, solvent temperature 80℃, and solvent concentration 3%;

[0082] ② Calculate the amount of sodium carbonate. The mass of sodium carbonate is 0.4855 kg;

[0083] ③ Weigh 0.4855 kg of sodium carbonate (analytical grade);

[0084] ④ Measure 15.7 kg of water, using the well site water source;

[0085] ⑤ Prepare the solution. Heat water to 80℃, slowly add sodium carbonate, and stir with a glass rod to help dissolve;

[0086] ⑥ After preparation, seal and store in a constant temperature incubator for later use.

[0087] Step 5: Fill in the model

[0088] ① Arrange the rock slices prepared in step 2 according to position 22 in step 1, as follows: Figure 1 As shown, the dissolution window faces inward, and the rock fragments are close together, bonded together with crystal glue to form a ring-shaped alkali ore body;

[0089] ② Preheat the model by turning on the model's temperature control unit and keeping the model temperature constant at 80℃ until the temperature remains constant.

[0090] ③ Fill the water storage unit with solvent;

[0091] ④ Keep the model temperature constant for 15 minutes.

[0092] Step 6: Dissolution Experiment

[0093] Turn on the water supply line pump to quickly fill the dissolving chamber with solvent; the time at this point is recorded as t0.

[0094] ② Turn on the return water pipeline pump; adjust the flow rate of the supply water pump and the return water pump to keep the liquid level in the dissolution chamber completely submerging the upper edge of the dissolution window of each rock fragment; at this point, a complete dissolution simulation experiment process has been established.

[0095] ③ Parameter recording and brine sampling: Within 1 hour, record the brine density value every 10 minutes and take a 5ml brine sample through the brine sampling unit; after 1 hour, record the brine density value every 1 hour and take a 5ml brine sample through the brine sampling unit; the brine needs to be tested for sodium carbonate and sodium chloride percentages.

[0096] ④ The dissolution experiment ends after 24 hours.

[0097] Step 7: Analysis of dissolution experiment data

[0098] ① Data on the density variation of brine are shown in Appendix Table 1, with time on the x-axis and density on the y-axis.

[0099] Plot a graph showing the density change of the brine, such as... Figure 4 As shown;

[0100] Table 1 Data from Single-Well Vertical Well Sanitation Production Simulation Experiment

[0101] Dissolution time <![CDATA[Brine density, g / cm 3 > Sodium carbonate concentration, % Sodium chloride concentration, % 0min 1.0287 2.97 0.000 10min 1.0391 4.66 0.002 20min 1.0511 5.53 0.004 30min 1.0587 6.24 0.006 40min 1.0677 7.12 0.008 50min 1.0743 8.18 0.010 60min 1.0818 9.09 0.013 2h 1.1000 10.88 0.014 3h 1.1168 11.61 0.016 4h 1.1246 13.03 0.018 5h 1.1393 13.46 0.018 6h 1.1435 14.54 0.020 7h 1.1595 15.26 0.022 8h 1.1637 16.50 0.023 9h 1.1706 16.89 0.024 24h 1.1970 18.50 0.027

[0102] ② The data on the change in the percentage content of sodium carbonate are shown in Table 1. A graph showing the change in the percentage content of sodium carbonate in the brine is plotted with time on the x-axis and the sodium carbonate percentage data on the y-axis, as shown below. Figure 5 As shown;

[0103] ③ The data on the change in the percentage content of sodium chloride are shown in Table 1. A graph showing the change in the percentage content of sodium chloride in the brine is plotted with time on the x-axis and the sodium chloride percentage data on the y-axis, as shown below. Figure 6 As shown;

[0104] ④ The above three data charts clearly show the dissolution effect of the dissolution mining scheme at different time points.

[0105] Step 8: Evaluation of dissolution effect

[0106] ① Determination of the optimal dissolution time. The first dissolution time corresponding to a sodium carbonate percentage content - A0 ≥ 10% is 4 hours, therefore the optimal dissolution time is 4 hours.

[0107] ② Preliminary evaluation of ore layer quality. The sodium chloride content corresponding to the optimal dissolution time is <1.2%, indicating that this deposit is a high-quality ore layer.

[0108] The leaching and mining effect of this ore layer was evaluated using the technical solution described in this invention, and the effect was significant. The evaluation experiment for the leaching and mining effect of single-well vertical fracturing is as follows:

[0109] Step 1: Obtain the physical simulation experimental setup

[0110] The physical simulation experimental device should include 6 modular units, namely, temperature control unit, dissolution experiment unit, water circulation unit, water storage unit, parameter measurement unit, and brine sampling unit.

[0111] Step 2: Sample preparation of alkali ore

[0112] ① Selection of core sections. Select soda ash ore sections with a thickness greater than 10cm, free of inclusions and argillaceous laminations;

[0113] ② Cut the rock core along the direction perpendicular to the rock strata to form a rock slice with a thickness of 5cm; the rock slice is 0.1m long and about 8cm wide; there are 8 rock slices in total; clean the rock slices with a brush and place them in a desiccator for later use;

[0114] ④ Carefully break the rock fragments to create irregular cracks. Each rock fragment needs to be broken to create 3-6 cracks, such as... Figure 3 As shown, carefully place in a desiccator for later use.

[0115] Step 3: Calculate and determine the amount of water V required for the simulation experiment. 模

[0116] ①The actual dissolution radius R of the production well is taken as 0.5m, and the model dissolution radius r is taken as 0.1m.

[0117] ② Calculate V according to formula (1) 模 It is 0.0157m 3 That is, 15.7 liters.

[0118] Step 4: Prepare the solvent

[0119] ① The solvent formulation in the solvent extraction scheme is specified as sodium carbonate solution, solvent temperature 80℃, and solvent concentration 3%;

[0120] ② Calculate the amount of sodium carbonate. The mass of sodium carbonate is 0.4855 kg;

[0121] ③ Weigh 0.4855 kg of sodium carbonate (analytical grade);

[0122] ④ Measure 15.7 kg of water, using the well site water source;

[0123] ⑤ Prepare the solution. Heat water to 80℃, slowly add sodium carbonate, and stir with a glass rod to help dissolve;

[0124] ⑥ After preparation, seal and store in a constant temperature incubator for later use.

[0125] Step 5: Fill in the model

[0126] ① Arrange the fragmented rock pieces prepared in step 2 at position 22 in step 1, as follows: Figure 1 As shown, the ore fragments are arranged in a circular pattern, with ceramic support particles laid on each crack surface to support the alkali ore fragments and prevent the crack surface from closing, thus forming a ring-shaped, fragmented alkali ore body.

[0127] ② Preheat the model by turning on the model's temperature control unit and keeping the model temperature constant at 80℃ until the temperature remains constant.

[0128] ③ Pour the solution prepared in step 4 into the water storage unit;

[0129] ④ Keep the model temperature constant for 15 minutes.

[0130] Step 6: Dissolution Experiment

[0131] ① Turn on the water supply line pump to quickly fill the dissolving chamber with solvent. Record the time at this point as 0.

[0132] ② Turn on the return water pipeline pump; adjust the flow rate of the supply water pump and the return water pump to keep the liquid level in the dissolution chamber completely submerging the upper edge of each rock fragment; at this point, a complete dissolution simulation experiment process has been established.

[0133] ③ Parameter recording and brine sampling: Within 1 hour, record the brine density value every 10 minutes and take a 5ml brine sample through the brine sampling unit; after 1 hour, record the brine density value every hour and take a 5ml brine sample through the brine sampling unit; the brine needs to be tested for sodium carbonate and sodium chloride content.

[0134] ④ The dissolution experiment ends after 24 hours.

[0135] Step 7: Analysis of dissolution experiment data

[0136] ① Data on the density variation of brine are shown in Table 2. The plot is calculated with time on the x-axis and density on the y-axis.

[0137] Plot a graph showing the density change of the brine, such as... Figure 7 As shown;

[0138] Table 2. Simulation data of single-well vertical well fracturing and leaching production experiment.

[0139]

[0140]

[0141] ② The data on changes in sodium carbonate content are shown in Table 2. A graph showing the changes in sodium carbonate content in the brine is plotted with time on the x-axis and sodium carbonate content data on the y-axis, as shown below. Figure 8 As shown;

[0142] ③ The data on changes in sodium chloride content are shown in Table 2. A graph depicting the changes in sodium chloride content in the brine is plotted with time on the x-axis and sodium chloride content data on the y-axis, as shown below. Figure 9 As shown;

[0143] ④ The above three data charts clearly show the dissolution effect of the dissolution mining scheme at different time points.

[0144] Step 8: Evaluation of dissolution effect

[0145] ① Determination of the optimal dissolution time. The first dissolution time corresponding to a sodium carbonate percentage content - A0 ≥ 10% is 2 hours, therefore the optimal dissolution time is 2 hours.

[0146] Preliminary evaluation of the ore layer quality: The optimal dissolution time corresponds to a sodium chloride content of <1.2%, indicating that this deposit is a high-quality ore layer.

[0147] By precisely controlling the water volume and solvent preparation in the simulation experiment, this invention can more effectively simulate the dissolution effect during actual mining, thereby improving mining efficiency. Furthermore, the physical simulation experimental device reduces direct mining of actual ore layers, conserving resources and lowering mining costs. Compared to traditional physical mining methods, the dissolution mining method is less environmentally damaging and more environmentally friendly. During the experiment, by plotting the changes in brine density, sodium carbonate, and sodium chloride percentages over time, the dissolution effect can be evaluated more accurately, providing data support for optimizing the mining process. Based on the experimental data, the optimal dissolution time can be determined, thereby optimizing the mining plan and improving resource utilization. Simultaneously, the preliminary evaluation of sodium chloride percentages allows for a more accurate assessment of ore layer quality, providing a basis for subsequent mining decisions. In addition, the physical simulation experimental device of this invention integrates multiple units such as temperature control, dissolution experiment, water circulation, water storage, parameter measurement, and brine sampling, achieving multi-functional integration and improving the convenience and accuracy of the experiment. This will promote the development of solid natural soda ash ore mining technology and provide new ideas and methods for technological innovation in related fields.

[0148] In summary, physical simulation experiments were conducted on the single-well vertical shaft leaching and single-well vertical shaft fracturing leaching processes of this mine using the technical solution described in this invention. Data on brine density, sodium carbonate percentage, and sodium chloride percentage during the leaching process were obtained. If the single-well vertical shaft leaching development method is used, the optimal leaching time is 4 hours; if the single-well vertical shaft fracturing leaching development method is used, the optimal leaching time is 2 hours, with twice the leaching efficiency. From the change in sodium chloride percentage, the sodium chloride percentage of this ore body is less than 1.2%, indicating a high-quality alkali deposit. Furthermore, by combining the brine density corresponding to the optimal leaching time with wellbore parameters and the optimal leaching time, the solvent injection rate, production rate, and daily alkali production can be further determined.

[0149] It should be noted that the specific manner in which each module performs its operation in the apparatus described in the above embodiments has been described in detail in the embodiments of the method, and will not be elaborated here.

[0150] The above description is merely an embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of the claims of this application.

Claims

1. An experimental method for evaluating the sintering and mining effect of solid natural soda ash ore, characterized in that, Includes the following steps: Step (1): Obtain the physical simulation experimental device and prepare the required alkali ore sample according to the sample specifications required by the dissolution unit in the physical simulation experimental device; Step (2): Calculate and determine the amount of water V required for the simulation experiment. 模 Then, the solvent is prepared; Step (3): Fill the model with the prepared solvent and conduct a dissolution experiment to obtain dissolution experiment data; Step (4): Analyze the dissolution experiment data and evaluate the effectiveness of the analysis results.

2. The experimental method for evaluating the sintering and mining effect of solid natural soda ash ore according to claim 1, characterized in that, The physical simulation experimental device includes a temperature control unit, a dissolution experimental unit, a water circulation unit, a water storage unit, a parameter measurement unit, and a brine sampling unit.

3. The experimental method for evaluating the sintering and mining effect of solid natural soda ash ore according to claim 1, characterized in that, In step (1), the sample specifications required by the dissolution unit in the physical simulation experimental device are as follows: select a soda ash ore section with a thickness greater than 10cm, wherein the soda ash ore section includes no inclusions and no muddy layers, select a rock core cut perpendicular to the rock layer direction to form a rock sheet with a thickness of 3-5cm and the same length.

4. The experimental method for evaluating the sintering and mining effect of solid natural soda ash ore according to claim 1, characterized in that, In step (2), the required water volume V for the simulation experiment is calculated and determined. 模 The calculation formula is as follows: V 模 =πRrh In the formula, V 模 To simulate the water volume required for the experiment, R is the dissolution radius of the ore layer, r is the dissolution radius of the model, and h is the length of the dissolution window under non-fracturing conditions.

5. The experimental method for evaluating the leaching and mining effect of solid natural soda ash ore according to claim 1, characterized in that, The preparation of the solvent in step (2) includes the following steps: Step (2.1): Determine the solvent formulation, solvent temperature T, and solvent concentration in the solvent extraction scheme; Step (2.2): Calculate the amount of solvent and weigh the solvent according to the amount of solvent; Step (2.3): Take water using well site water source, distilled water or deionized water; Step (2.4): Heat water to temperature T, slowly add solvent, stir with a glass rod to dissolve, and obtain the prepared solution; Step (2.5): After preparation, seal the container and store it in a constant temperature incubator for later use.

6. The experimental method for evaluating the sintering and mining effect of solid natural soda ash ore according to claim 1, characterized in that, The step (3) of filling the model with the prepared solvent includes the following steps: Step (3.1): In non-fracturing mining, crystal glue is used to bond rock flakes to form annular alkali ore bodies; while in fracturing mining, support particles are laid on the fracture surface and the fragmented rock flakes are bonded together to form annular, fragmented alkali ore bodies. Step (3.2): Turn on the model's temperature control unit to preheat the model and set the constant temperature to T; Step (3.3): Fill the water storage unit with solvent; Step (3.4): After the model temperature is kept constant for 15 minutes, the density of the brine is measured as g0 and the percentage of sodium carbonate is A0, and then the model is filled.

7. The experimental method for evaluating the sintering and mining effect of solid natural soda ash ore according to claim 6, characterized in that, The dissolution experiment in step (3) includes the following steps: Step (3.5): Turn on the water supply pipeline pump and fill the dissolving chamber with solvent. The time at this time is recorded as t0. Step (3.6): Adjust the flow rate of the water supply pump and the return pump to keep the liquid level in the dissolution chamber completely submerging the upper edge of the dissolution window of each rock fragment, and obtain the complete dissolution simulation experiment process; Step (3.7): In the dissolution simulation experiment, record parameters and take brine samples; Step (3.8): After 24 hours of the experiment, the dissolution experiment is ended.

8. The experimental method for evaluating the sintering and mining effect of solid natural soda ash ore according to claim 1, characterized in that, The analysis of the dissolution experiment data in step (4) includes: determining the dissolution effect at different time points by drawing a diagram of the change in brine density, a diagram of the change in the percentage of sodium carbonate in brine, and a diagram of the change in the percentage of sodium chloride in brine.

9. The experimental method for evaluating the sintering and mining effect of solid natural soda ash ore according to claim 8, characterized in that, The chart showing the change in brine density is a graph with time on the horizontal axis and density on the vertical axis; the chart showing the change in the percentage of sodium carbonate content in brine is a graph with time on the horizontal axis and sodium carbonate content on the vertical axis; the chart showing the change in the percentage of sodium chloride content in brine is a graph with time on the horizontal axis and sodium chloride content on the vertical axis.

10. The experimental method for evaluating the sintering and mining effect of solid natural soda ash ore according to claim 1, characterized in that, The effect evaluation of the analysis results in step (4) includes: determining the optimal dissolution time and preliminarily evaluating the quality of the ore layer by the percentage content of sodium chloride.

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