A tailings sand-based grouting material and a method of preparing the same

Abstract

This application relates to a grouting material based on tailings sand and its preparation method, belonging to the field of grouting material technology. The grouting material based on tailings sand comprises component A and component B. This application utilizes lead-zinc tailings sand placed in an alkaline environment to enhance the gelation activity of its main component, feldspar. Through proper proportioning, it rapidly solidifies and maintains high strength under the combined action of water glass, sodium carbonate, and calcium hydroxide. Furthermore, the grouting material uses commonly used raw materials, ensuring ample market supply and convenient procurement. It also enables the resource utilization of tailings sand, resulting in significant economic and social benefits.

Description

Technical Field

[0001] This application relates to the field of grouting materials technology, and in particular to a grouting material based on tailings sand and its preparation method. Background Technology

[0002] In the mining process, the dispersed distribution, low grade, and complex beneficiation of non-ferrous metals such as lead and zinc result in the generation of large amounts of waste rock and tailings. Large stockpiles of lead-zinc tailings not only occupy land resources but also cause serious pollution to surrounding water bodies and farmland. Therefore, the resource-based reuse of lead-zinc tailings can not only achieve comprehensive tailings recovery but also enable large-scale disposal and transformation of tailings, turning waste into treasure and reducing the adverse ecological impact of tailings at the source.

[0003] In existing technologies, the main ways to comprehensively utilize tailings sand include filling mining voids and producing building materials, but the overall utilization rate and added value are relatively low.

[0004] Currently, when using existing grouting materials (such as clay curing, polyurethane, or cement-based materials) for waterproofing, there are common problems such as slow setting speed, high material cost, and low added value of comprehensive utilization. Especially in seepage sites with low static head pressure and low flow velocity, the long setting time of traditional grouting materials affects construction efficiency. Summary of the Invention

[0005] To address or partially address the problems existing in related technologies, this application provides a grouting material based on tailings sand and its preparation method, thereby realizing the resource utilization of tailings sand and achieving good economic and social benefits.

[0006] The first aspect of this application provides a grouting material based on tailings sand, the grouting material comprising component A and component B; Component A comprises the following raw materials by weight percentage: calcium hydroxide 12.7%–19.3%, tailings sand 55%–61%, water-reducing agent 0.09%–0.11%, with the balance being water; The tailings sand includes lead-zinc mine tailings sand; Component B comprises the following raw materials by weight percentage: sodium hydroxide 6.6%–10.4%, sodium carbonate 10.0%–19.4%, water glass 64%–75%, with the balance being water; The weight ratio of component A to component B is 3.3:1 to 5.1:1.

[0007] Optionally, in some implementations of the first aspect: The specific parameters of the lead-zinc mine tailings sand are as follows: density is 2.9 g / cm³~3.0 g / cm³, specific surface area is 450 m² / kg~460 m² / kg, sulfur trioxide content is 1.6%~1.8%, chloride ion content is 0.03%~0.04%, and loss on ignition is 33%~35%.

[0008] Optionally, in some implementations of the first aspect: The specific parameters of this water glass are as follows: modulus of 3.1 to 3.4, sodium oxide content of 8.5% to 10%, silicon dioxide content of 26% to 29%, and density of 1.3 g / cm³ to 1.4 g / cm³.

[0009] Optionally, in some implementations of the first aspect: When grouting, the grouting material adopts a two-liquid grouting method, in which the A component and the B component are mixed at a preset weight ratio to obtain a grouting material based on tailings sand for grouting.

[0010] Optionally, in some implementations of the first aspect: This water-reducing agent is a polycarboxylate type water-reducing agent.

[0011] Optionally, in some implementations of the first aspect: The grouting material also includes: an expanding agent; The expanding agent is a sulfur-aluminum expanding agent, accounting for 0.5% to 3% of the total weight of the grouting material.

[0012] Optionally, in some implementations of the first aspect: The grouting material also includes: stabilizers; The stabilizer can be hydroxypropyl methylcellulose, accounting for 0.1% to 0.5% of the total weight of the grouting material.

[0013] A second aspect of this application provides a method for preparing a tailings sand-based grouting material. This method, used to prepare the aforementioned tailings sand-based grouting material, includes: Preparation of Component A: Weigh each component according to the designed ratio, mix the weighed tailings sand, calcium hydroxide, water-reducing agent and water evenly to obtain slurry, which is Component A; Preparation of Component B: Weigh each component according to the designed ratio, mix the weighed water glass and water, add sodium hydroxide, stir to obtain a homogeneous liquid, add sodium carbonate, mix well to obtain a slurry, which is Component B.

[0014] Optionally, in some implementations of the second aspect: The preparation of component A specifically includes: First, add the weighed tailings sand and calcium hydroxide to the mixing tank and mix well; Then add polycarboxylate superplasticizer; Finally, add water and turn on the mixer to stir at high speed until a homogeneous fluid is obtained. During mixing, use a hand-held mixer to stir for 10-20 seconds every 5 minutes to prevent settling.

[0015] Optionally, in some implementations of the second aspect: The preparation of component B specifically includes: First, add the weighed water glass and water to the mixing bowl and stir well; Then add sodium hydroxide and stir. After stirring to obtain a homogeneous liquid, slowly add sodium carbonate in small amounts several times to prevent the formation of insoluble lumps.

[0016] The technical solution provided in this application may include the following beneficial effects: This application places lead-zinc tailings sand in an alkaline environment, enabling the main component, feldspar, to exhibit high gelation activity. Through a rational formulation, and with the combined action of water glass, sodium carbonate, and calcium hydroxide, it rapidly solidifies and maintains high strength. Furthermore, the grouting material uses commonly available raw materials, ensuring ample market supply and convenient procurement. This also allows for the resource utilization of tailings sand, resulting in significant economic and social benefits.

[0017] This application relates to a grouting material based on tailings sand, which can be used in the field of groundwater disaster management in tunnels, water conservancy and hydropower projects, metal mines or waste treatment systems. It is particularly suitable for water hazard treatment in shallow surface seepage sites with low static head pressure (<70m) and low flow velocity (<0.2m / s), such as seepage grouting treatment in tunnels, reservoirs, tailings ponds in shallow mines, landfills and other places.

[0018] 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

[0019] The above and other objects, features and advantages of this application will become more apparent from the more detailed description of exemplary embodiments thereof in conjunction with the accompanying drawings, wherein the same reference numerals generally represent the same components in the exemplary embodiments thereof.

[0020] Figure 1 This is a schematic diagram of the process structure of the preparation method of grouting material based on tailings sand in the embodiments of this application. Detailed Implementation

[0021] Embodiments of this application will now be described in more detail with reference to the accompanying drawings. While embodiments of this application are shown in the drawings, it should be understood that this application may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided to make this application more thorough and complete, and to fully convey the scope of this application to those skilled in the art.

[0022] In the mining process, the dispersed distribution, low grade, and complex beneficiation of non-ferrous metals such as lead and zinc result in the generation of large amounts of waste rock and tailings. Large stockpiles of lead-zinc tailings not only occupy land resources but also cause serious pollution to surrounding water bodies and farmland. Therefore, the resource-based reuse of lead-zinc tailings can not only achieve comprehensive tailings recovery but also enable large-scale disposal and transformation of tailings, turning waste into treasure and reducing the adverse ecological impact of tailings at the source.

[0023] In existing technologies, the main ways to comprehensively utilize tailings sand include filling mining voids and producing building materials, but the overall utilization rate and added value are relatively low.

[0024] Currently, when using existing grouting materials (such as clay curing, polyurethane, or cement-based materials) for waterproofing, there are common problems such as slow setting speed, high material cost, and low added value of comprehensive utilization. Especially in seepage sites with low static head pressure and low flow velocity, the long setting time of traditional grouting materials affects construction efficiency.

[0025] To address the aforementioned issues, this application provides a grouting material based on tailings sand and its preparation method, thereby realizing the resource utilization of tailings sand and achieving good economic and social benefits.

[0026] The technical solutions of the embodiments of this application are described in detail below with reference to the accompanying drawings.

[0027] A grouting material based on tailings sand, the grouting material comprising component A and component B; Component A comprises the following raw materials by weight percentage: calcium hydroxide 12.7%–19.3%, tailings sand 55%–61%, water-reducing agent 0.09%–0.11%, with the balance being water; The tailings include lead-zinc mine tailings.

[0028] Specifically, the parameters of the tailings sand of this lead-zinc mine are as follows: density is 2.9 g / cm³~3.0 g / cm³, specific surface area is 450 m² / kg~460 m² / kg, sulfur trioxide content is 1.6%~1.8%, chloride ion content is 0.03%~0.04%, and loss on ignition is 33%~35%.

[0029] Specifically: the water-reducing agent is a polycarboxylate type water-reducing agent.

[0030] Component B comprises the following raw materials by weight percentage: sodium hydroxide 6.6%–10.4%, sodium carbonate 10.0%–19.4%, water glass 64%–75%, with the balance being water.

[0031] Specifically, the parameters of this water glass are as follows: modulus of 3.1 to 3.4, sodium oxide content of 8.5% to 10%, silicon dioxide content of 26% to 29%, and density of 1.3 g / cm³ to 1.4 g / cm³.

[0032] The weight ratio of component A to component B is 3.3:1 to 5.1:1.

[0033] In this embodiment, lead-zinc tailings sand is the main raw material in component A, which mainly includes quartz, feldspar and mica. Under the stimulation of component B, it will have high cementing activity. The principle is that alkalization causes the Al-O-Al bonds in feldspar to break and then recombine. The specific reactions of feldspar components under alkali activation are as follows: First step: Feldspar generates orthosilicate hydrate molecules or calcium disilicate (CSH) molecules under alkali activation, releasing aluminum hydroxide gel, non-glassy silicon units, or magnesium hydroxide gel. Second step: Orthosilicate hydrate molecules condense with calcium disilicate to form tetragonal orthosilicate-disilicate molecules [Si-O-Al-SiO-Si-O]. Simultaneously, introducing water glass into the main cementitious material increases orthosilicate hydrate production, significantly promoting the forward reaction in the second step and shortening the setting time. To improve the system's strength during later curing and further shorten the setting time, introducing a carbon source, sodium carbonate, consumes large amounts of calcium hydroxide, aluminum hydroxide gel, and magnesium hydroxide gel, generating insoluble precipitates, while simultaneously promoting the forward alkali activation reaction and further shortening the setting time.

[0034] While the introduction of sodium carbonate can increase early strength, the decrease in pH leads to a reduction in calcium hydroxide and other gels, thus lowering later strength. Simultaneously, the introduction of water glass accelerates the reaction, generating numerous unstable defects and reducing later strength. Therefore, this application further introduces a long-term, stable, and excessive alkali source, namely calcium hydroxide, to ensure later strength. Furthermore, due to the low solubility of calcium hydroxide, the calcium hydroxide gel in the system is ensured to remain relatively abundant over the long term as it is continuously consumed.

[0035] In summary, this application places lead-zinc tailings sand in an alkaline environment, enabling the main component, feldspar, to exhibit high gelation activity. Through a rational formulation, and with the combined action of water glass, sodium carbonate, and calcium hydroxide, it rapidly solidifies and maintains high strength. Furthermore, the grouting material uses commonly available raw materials, ensuring ample market supply and convenient procurement. This also allows for the resource utilization of tailings sand, resulting in significant economic and social benefits.

[0036] This application relates to a grouting material based on tailings sand, which can be used in the field of groundwater disaster management in tunnels, water conservancy and hydropower projects, metal mines or waste treatment systems. It is particularly suitable for water hazard treatment in shallow surface seepage sites with low static head pressure (<70m) and low flow velocity (<0.2m / s), such as seepage grouting treatment in tunnels, reservoirs, tailings ponds in shallow mines, landfills and other places.

[0037] Specifically: When grouting, the grouting material adopts a two-liquid grouting method, in which the A component and the B component are mixed in a preset weight ratio to obtain a grouting material based on tailings sand for grouting.

[0038] In this embodiment, a "two-component grouting" process is adopted, in which components A and B are stored and pumped separately and mixed only momentarily at the grouting orifice, which facilitates on-site construction.

[0039] Specifically, the grouting material also includes an expanding agent; the expanding agent is a sulfur-aluminum expanding agent, accounting for 0.5% to 3% of the total weight of the grouting material.

[0040] In this embodiment, by adding an expansion agent when necessary, the grout can be more tightly bonded to the surrounding matrix, reducing the generation of shrinkage cracks, improving impermeability, and ensuring construction quality.

[0041] Specifically, the grouting material also includes a stabilizer; the stabilizer may be hydroxypropyl methylcellulose, accounting for 0.1% to 0.5% of the total weight of the grouting material.

[0042] In this embodiment, by adding a stabilizer when necessary, the viscosity and water retention of the grout can be increased, ensuring the uniformity of the grout components and guaranteeing the construction quality.

[0043] Corresponding to the foregoing embodiments, this application also provides a method for preparing grouting materials based on tailings sand and corresponding embodiments.

[0044] Figure 1 This is a schematic diagram of the process structure of the preparation method of grouting material based on tailings sand in the embodiments of this application.

[0045] See Figure 1 A method for preparing a tailings sand-based grouting material, the method comprising: S100: Preparation of Component A: Weigh each component according to the design ratio, mix the weighed tailings sand, calcium hydroxide, water-reducing agent and water evenly to obtain slurry, which is Component A.

[0046] Specifically: the preparation of component A includes: S101: First, add the weighed tailings sand and calcium hydroxide to the mixing tank and mix evenly; S102: Polycarboxylate superplasticizer is then added; S103: Finally, add water and turn on the mixer to stir at high speed until a homogeneous fluid is obtained. During mixing, use a hand-held mixer to stir for 10-20 seconds every 5 minutes to prevent settling.

[0047] S:200: Preparation of component B: Weigh each component according to the designed ratio, mix the weighed water glass and water, add sodium hydroxide, stir to obtain a homogeneous liquid, add sodium carbonate, mix well to obtain a slurry, which is component B.

[0048] Specifically: the preparation of component B includes: S201: First, add the weighed water glass and water to the mixing bowl and stir well; S202: Then add sodium hydroxide and stir; S203: After stirring to obtain a homogeneous liquid, slowly add sodium carbonate in small amounts several times to prevent the formation of insoluble lumps.

[0049] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0050] The performance index tests in this application embodiment are based on the following standards: The final setting time was tested in accordance with the "Test Methods for Standard Consistency Water Requirement, Setting Time and Soundness of Cement (GB / T1346-2011)". The flow spread (SL) was tested in accordance with the "Technical Specification for Application of Cement-based Grouting Materials (GB / T50448-2015)". The gelation time was measured using a rapid detection method. Timing began when components A and B were mixed, and the mixture was poured back and forth between two paper cups until it could no longer be poured out, at which point the timing stopped. The strength and permeability of the test blocks were determined according to the "Test Method for Strength of Cement Mortar (ISO Method) (GB / T17671-1999)," which included the preparation, curing, and testing of the test blocks.

[0051] Example 1 This embodiment 11 provides a grouting material based on tailings sand. The grouting material includes component A and component B. Component A includes the following raw materials by weight percentage: calcium hydroxide 14.01%, lead-zinc ore tailings sand 60.69%, polycarboxylate superplasticizer 0.10%, and water 25.2%. Component B includes the following raw materials by weight percentage: sodium hydroxide 10.22%, sodium carbonate 10.22%, water glass 74.09%, and water 5.47%. The weight ratio of component A to component B is 3.6:1.

[0052] In this embodiment, the tailings sand used is lead-zinc mine tailings sand, with the following specific parameters: density of 2.97 g / cm³, specific surface area of ​​455 m² / kg, sulfur trioxide content of 1.73%, chloride ion content of 0.035%, and loss on ignition of 34.4%. This embodiment also provides a method for preparing the above-mentioned tailings sand-based grouting material, which includes the following steps: Preparation of components S1 and A Add tailings sand and calcium hydroxide to the mixing tank and mix thoroughly. Then add polycarboxylate superplasticizer. Add water and turn on the mixer to stir at high speed until a fluid is formed, thus obtaining component A. Component A should be used as soon as possible after preparation. Every 5 minutes, it needs to be stirred with a hand-held mixer for 10 to 20 seconds to prevent sedimentation.

[0053] Preparation of components S2 and B First, add water glass and water to the mixing tank and stir until homogeneous. Then, add sodium hydroxide and stir until a homogeneous liquid is obtained. Next, slowly add sodium carbonate in small amounts several times to prevent the formation of insoluble lumps. After mixing thoroughly, component B is obtained. Stir with a hand-held mixer for 10-20 seconds every 5 minutes to prevent loss of fluidity. The slurry should be used as soon as possible after preparation, and the storage time should not exceed 20 hours.

[0054] During grouting, a two-liquid grouting method is adopted, in which the A component and the B component are mixed according to a preset weight ratio to obtain a grouting material based on tailings sand, which is denoted as grouting material I.

[0055] In this embodiment 1, the relevant indicators of intermediate component A, component B, grouting material I, and the performance of the stone body were also measured, and the specific contents are as follows.

[0056] 1. In this example 1, the density, viscosity, flowability, initial spread and pumpability of component A were investigated, and the density, viscosity and flowability of component B were investigated. The specific results are shown in Table 1.

[0057] Table 1 2. In this example 1, the density, initial setting time and final setting time of grouting material I were investigated. The specific results are shown in Table 2.

[0058] Table 2 3. In this example 1, the compressive strength and flexural strength of the grouting material I stone body were investigated. The specific results are shown in Table 3.

[0059] Table 3 Example 2 This embodiment 2 provides a grouting material based on tailings sand. The grouting material includes component A and component B. Component A includes the following raw materials by weight percentage: calcium hydroxide 13.63%, lead-zinc ore tailings sand 59.04%, polycarboxylate superplasticizer 0.10%, and water 27.24%. Component B includes the following raw materials by weight percentage: sodium hydroxide 10.22%, sodium carbonate 10.22%, water glass 74.09%, and water 5.47%. The weight ratio of component A to component B is 3.6:1.

[0060] In this embodiment 2, the tailings sand used is lead-zinc mine tailings sand, with the following specific parameters: density is... It has a content of 2.91 g / cm³, a specific surface area of ​​460 m² / kg, a sulfur trioxide content of 1.62%, a chloride ion content of 0.031%, and a loss on ignition of 33.12%.

[0061] Example 2 also provides a method for preparing the above-mentioned tailings sand-based grouting material, which is the same as the preparation method in Example 1. The tailings sand-based grouting material obtained by mixing component A and component B is denoted as grouting material II. Example 2 also measured the relevant indicators of intermediate component A, component B, grouting material II, and the properties of the slag body, as detailed below.

[0062] 1. In this Example 2, the density, viscosity, flowability, initial spread and pumpability of component A were investigated, and the density, viscosity and flowability of component B were investigated. The specific results are shown in Table 4.

[0063] Table 4 2. In this Example 2, the density, initial setting time and final setting time of grouting material II were investigated. The specific results are shown in Table 5.

[0064] Table 5 3. In this Example 2, the compressive strength and flexural strength of the grouting material II stone body were investigated. The specific results are shown in Table 6.

[0065] Table 6 Example 3 This embodiment 3 provides a grouting material based on tailings sand. The grouting material includes component A and component B. Component A includes the following raw materials by weight percentage: calcium hydroxide 12.74%, lead-zinc ore tailings sand 55.17%, polycarboxylate superplasticizer 0.09%, and water 32.0%. Component B includes the following raw materials by weight percentage: sodium hydroxide 8.26%, sodium carbonate 12.18%, water glass 73.24%, and water 6.32%. The weight ratio of component A to component B is 4.2:1.

[0066] In this embodiment 3, the tailings sand used is lead-zinc mine tailings sand, with the following specific parameters: density is... It has a content of 3.0 g / cm³, a specific surface area of ​​452 m² / kg, a sulfur trioxide content of 1.79%, a chloride ion content of 0.04%, and a loss on ignition of 34.85%.

[0067] This embodiment 3 also provides a method for preparing the above-mentioned tailings sand-based grouting material, which is the same as the preparation method in embodiment 1. The tailings sand-based grouting material obtained by mixing component A and component B is referred to as grouting material III.

[0068] This embodiment 3 also discusses the phase relationship of intermediate component A, component B, grouting material III, and the properties of the slurry body. The relevant indicators were measured, and the details are as follows.

[0069] 1. In this Example 3, the density, flowability, initial spread and pumpability of component A were investigated, and the density, viscosity and flowability of component B were investigated. The specific results are shown in Table 7.

[0070] Table 7 2. In this embodiment 3, the density, initial setting time and final setting time of grouting material III were investigated. The specific results are shown in Table 8.

[0071] Table 8 3. In this embodiment 3, the compressive strength and flexural strength of the grouting material III stone body were investigated. The specific results are shown in Table 9.

[0072] Table 9 Example 4 This embodiment 4 provides a grouting material based on tailings sand. The grouting material includes component A and component B. Component A includes the following raw materials by weight percentage: calcium hydroxide 19.23%, lead-zinc ore tailings sand 56.47%, polycarboxylate superplasticizer 0.1%, and water 24.2%. Component B includes the following raw materials by weight percentage: sodium hydroxide 6.64%, sodium carbonate 19.43%, water glass 64.45%, and water 9.48%. The weight ratio of component A to component B is 5.1:1.

[0073] In this example, the tailings sand used is lead-zinc mine tailings sand, with the following specific parameters: density of 2.97 g / cm³, specific surface area of ​​455 m² / kg, sulfur trioxide content of 1.73%, chloride ion content of 0.035%, and loss on ignition of 34.4%.

[0074] In this embodiment 4, relevant indicators of intermediate component A, component B, grouting material IV, and the performance of the grouting body were also measured, as detailed below.

[0075] 1. In this Example 4, the density and flowability of component A and the density and viscosity of component B were investigated. The specific results are shown in Table 10.

[0076] Table 10 2. In this example 4, the density, initial setting time and final setting time of grouting material IV were investigated. The specific results are shown in Table 11.

[0077] Table 11 3. In this example 4, the compressive strength and flexural strength of the grouting material IV stone body were investigated. The specific results are shown in Table 12.

[0078] Table 12 Example 5 Analysis of the performance of the four tailings sand-based grouting materials prepared in Examples 1-4 showed that the initial setting time of the grouting materials was 46 min-102 min, the final setting time was 88 min-262 min, and the density was 1.73 g / cm³-1.80 g / cm³. After curing for 2 hours, the compressive strength of the grouting material was 0.31 MPa-0.72 MPa, and the flexural strength was 0.09 MPa-0.21 MPa. After curing for 28 days, the compressive strength of the grouting material was 1.92 MPa-3.5 MPa, and the flexural strength was 0.53 MPa-0.79 MPa.

[0079] By comprehensively evaluating its initial setting time, final setting time, density, and compressive and flexural strength of the stone body during curing, the grouting material, with its characteristics of rapid setting, appropriate compressive and flexural strength, and in conjunction with suitable technological means, can be applied to the field of groundwater disaster management in tunnels, water conservancy and hydropower projects, metal mines, or waste treatment systems to quickly seal leakage channels and achieve the purpose of treatment.

[0080] The grouting material based on tailings sand provided by this invention is particularly suitable for water hazard treatment in seepage sites with low static head pressure (<70m) and low flow velocity (<0.2m / s), such as grouting treatment for seepage in tunnels, reservoirs, tailings ponds in shallow mines, and landfills.

[0081] Depending on actual needs, an expansion agent may be used as needed to achieve a better sealing effect, thereby strengthening the bond between the grout and the injected body and forming a more tightly sealed water-blocking curtain.

[0082] To better demonstrate the effectiveness of the grouting material in this application, further explanation is provided through proportions.

[0083] Comparative Example 1 This comparative example provides a grouting material, which is a commonly used material in the art, prepared from cement and fly ash in a 6:4 ratio and a water-to-solid ratio of 0.5:1, denoted as Grouting Material Pair I. The density, fluidity, bleeding time, bleeding rate, initial setting time, final setting time, and compressive strength of the stone mass after 28 days of curing of Grouting Material Pair I were measured. The specific results are shown in Table 13 below.

[0084] Table 13 As can be seen from the comparison of the data in Table 13 with the corresponding indicators in the embodiments, the grouting material based on tailings sand provided by the present invention has better fluidity and a significantly faster setting speed than commonly used cement-fly ash grouting materials. It also has the characteristic of no bleeding, but the setting strength of the grout body is slightly worse.

[0085] Comparative Example 2 Comparative Example 1 provides a tailings sand-based grouting material. The raw materials and preparation method of the tailings sand-based grouting material in this comparative example are basically the same as those in Example 1. The only difference is that, in terms of raw materials, lead-zinc mine tailings sand is replaced with an equal amount of "fly ash". The types and amounts of other raw materials are the same as those in Example 1. The product obtained by mixing component A and component B is denoted as tailings sand-based grouting material II.

[0086] The fly ash used in this invention is obtained by grinding Grade I low-calcium fly ash (UFA, D50 = 2.26 μm) using a ball mill. It contains the following chemical components by weight: 49.3% silica, 40.3% alumina, 3.1% iron oxide, 5.1% calcium oxide, 1.12% sulfur trioxide, and 1.1% LOI. The density, fluidity, bleeding time, bleeding rate, initial setting time, final setting time, and compressive strength of the grouting material (Type II) after 28 days of curing were measured. The specific results are shown in Table 14 below.

[0087] Table 14 As can be seen from the comparison of the data in Table 14 with the corresponding indicators in Example 1, the grouting material based on tailings sand provided by the present invention has a significantly faster setting speed than the fly ash grouting material, and also has advantages such as no bleeding and strong slab setting strength.

[0088] The technical solution provided in this application has the following beneficial effects: This application places lead-zinc tailings sand in an alkaline environment, enabling the main component, feldspar, to exhibit high gelation activity. Through a rational formulation, and with the combined action of water glass, sodium carbonate, and calcium hydroxide, it rapidly solidifies and maintains high strength. Furthermore, the grouting material uses commonly available raw materials, ensuring ample market supply and convenient procurement. This also allows for the resource utilization of tailings sand, resulting in significant economic and social benefits.

[0089] This application relates to a grouting material based on tailings sand, which can be used in the field of groundwater disaster management in tunnels, water conservancy and hydropower projects, metal mines or waste treatment systems. It is particularly suitable for water hazard treatment in shallow surface seepage sites with low static head pressure (<70m) and low flow velocity (<0.2m / s), such as seepage grouting treatment in tunnels, reservoirs, tailings ponds in shallow mines, landfills and other places.

[0090] The various embodiments of this application have been described above. These descriptions are exemplary and not exhaustive, nor are they limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments. The terminology used herein is chosen to best explain the principles, practical application, or improvement of the technology in the market, or to enable others skilled in the art to understand the embodiments disclosed herein.

Claims

1. A grouting material based on tailings sand, characterized in that: The grouting material includes component A and component B; Component A comprises the following raw materials by weight percentage: calcium hydroxide 12.7%–19.3%, tailings sand 55%–61%, water-reducing agent 0.09%–0.11%, and the balance being water; The tailings sand includes lead-zinc mine tailings sand. Component B comprises the following raw materials by weight percentage: sodium hydroxide 6.6%–10.4%, sodium carbonate 10.0%–19.4%, water glass 64%–75%, with the balance being water; The weight ratio of component A to component B is 3.3:1 to 5.1:

1.

2. The grouting material based on tailings sand according to claim 1, characterized in that: The specific parameters of the lead-zinc mine tailings sand are as follows: density of 2.9 g / cm³ to 3.0 g / cm³, specific surface area of ​​450 m² / kg to 460 m² / kg, sulfur trioxide content of 1.6% to 1.8%, chloride ion content of 0.03% to 0.04%, and loss on ignition of 33% to 35%.

3. The grouting material based on tailings sand according to claim 2, characterized in that: The specific parameters of the water glass are as follows: modulus of 3.1 to 3.4, sodium oxide content of 8.5% to 10%, silicon dioxide content of 26% to 29%, and density of 1.3 g / cm³ to 1.4 g / cm³.

4. The grouting material based on tailings sand according to claim 3, characterized in that: When the grouting material is used for grouting, a two-liquid grouting method is adopted, in which the A component and the B component are mixed at a preset weight ratio to obtain a grouting material based on tailings sand for grouting.

5. The grouting material based on tailings sand according to claim 4, characterized in that: The water-reducing agent is a polycarboxylate-type water-reducing agent.

6. The grouting material based on tailings sand according to any one of claims 1-5, characterized in that: The grouting material also includes: an expanding agent; The expanding agent is a sulfur-aluminum expanding agent, accounting for 0.5% to 3% of the total weight of the grouting material.

7. The grouting material based on tailings sand according to claim 6, characterized in that: The grouting material also includes: a stabilizer; The stabilizer can be hydroxypropyl methylcellulose, accounting for 0.1% to 0.5% of the total weight of the grouting material.

8. A method for preparing a grouting material based on tailings sand, characterized in that, The preparation method is used to prepare the grouting material based on tailings sand as described in any one of claims 1 to 7, and the preparation method includes: Preparation of Component A: Weigh each component according to the designed ratio, mix the weighed tailings sand, calcium hydroxide, water-reducing agent and water evenly to obtain slurry, which is Component A; Preparation of Component B: Weigh each component according to the designed ratio, mix the weighed water glass and water, add sodium hydroxide, stir to obtain a homogeneous liquid, add sodium carbonate, mix well to obtain a slurry, which is Component B.

9. The preparation method according to claim 8, characterized in that: The preparation of component A specifically includes: First, add the weighed tailings sand and calcium hydroxide to the mixing tank and mix well; Then add polycarboxylate superplasticizer; Finally, add water and turn on the mixer to stir at high speed until a homogeneous fluid is obtained. During mixing, use a hand-held mixer to stir for 10-20 seconds every 5 minutes to prevent settling.

10. The preparation method according to claim 9, characterized in that: The preparation of component B specifically includes: First, add the weighed water glass and water to the mixing bowl and stir well; Then add sodium hydroxide and stir. After stirring to obtain a homogeneous liquid, slowly add sodium carbonate in small amounts several times to prevent the formation of insoluble lumps.

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