An acid-resistant plugging grouting material suitable for acid mine water treatment and a preparation method and application thereof

Abstract

This invention discloses an acid-resistant sealing grouting material suitable for the treatment of acidic mine water inrush, its preparation method, and its application. It belongs to the technical field of mine groundwater pollution prevention and control and mine water hazard management. The acid-resistant sealing grouting material, by weight, comprises: 8-12 parts nano-hydroxyapatite, 1.5-3 parts sodium alginate, 5-8 parts porous adsorbent material, 100 parts cement, 25-35 parts water glass, 3-5 parts quicklime, 0.5-1.0 parts retarder, and 50-65 parts water. The acid-resistant sealing grouting material of this invention can immobilize iron and manganese, exhibits strong acid resistance and good pressure resistance, and is suitable for grouting materials used in sealing goaf areas and fissures in closed mines.

Description

Technical Field

[0001] This invention belongs to the field of mine groundwater pollution prevention and control and mine water hazard management technology, specifically relating to an acid-resistant sealing grouting material suitable for the treatment of acidic mine water inrush, its preparation method and application. Background Technology

[0002] Acidic mine water is acidic wastewater formed by a series of chemical reactions in which sulfur-containing minerals react with air, water, and microorganisms. Its core characteristics are high concentrations of iron, manganese, and sulfates. When a mine is closed, groundwater drainage is often stopped. Sulfur-containing minerals in the surrounding rocks and strata are then immersed in mine water for extended periods, easily forming iron- and manganese-rich acidic mine water. This causes pollution of the mining area and surrounding water bodies, and sometimes even threatens the safety of drinking water sources.

[0003] Existing sealing materials are mostly ordinary cement-based or cement-water glass systems, which are easily corroded, weakened, and fail to prevent seepage in acidic environments, making it difficult to stably block dominant groundwater recharge channels in the long term. Therefore, there is an urgent need to develop a grouting material that is highly acid-resistant, has good fluidity, high consolidation strength, and excellent seepage prevention performance, suitable for sealing goaf areas and fissures in closed mines. Summary of the Invention

[0004] To address the aforementioned technical problems, this invention provides an acid-resistant sealing grouting material suitable for treating water inrush in acidic mines, its preparation method, and its application.

[0005] Terminology Explanation:

[0006] Unless otherwise defined, all technical terms used herein have the same meanings as commonly understood by one of ordinary skill in the art. Unless otherwise stated, all patents, patent inventions, and publications cited in this document are incorporated herein by reference in their entirety. If multiple definitions exist for terms, the definition provided in this chapter shall prevail.

[0007] It should be understood that the above brief description and the following detailed description are exemplary and for illustrative purposes only, and do not limit the subject matter of the invention in any way. In this invention, the singular is used in conjunction with the plural unless otherwise specifically stated. It should also be noted that, unless otherwise stated, the use of “or” or “or” means “and / or”. Furthermore, the use of the term “comprising” and other forms such as “including,” “containing,” and “contains” are not limiting.

[0008] Unless specifically defined herein, the use of all commercially available products herein employs standard techniques. For example, it may be carried out using the manufacturer's instructions for use with the kit, or in accordance with methods known in the art or the description of this invention. The techniques and methods described herein can generally be implemented according to conventional methods well known in the art, based on the descriptions in the various summary and more specific documents cited and discussed in this specification.

[0009] The terms “optional / arbitrary” or “optionally / arbitrarily” mean that the event or situation described below may or may not occur, including both the occurrence and non-occurrence of the event or situation.

[0010] The term "leak-sealing material" as used in this article refers to functional materials used to seal acidic mine water inflow, fill fissures in surrounding rock and voids in goaf areas, and block water inflow channels. In this invention, it specifically refers to acid-resistant sealing grouting materials containing components such as nano-hydroxyapatite, sodium alginate, and porous adsorbent materials.

[0011] The term "preferred supply channel" used in this article refers to the main pathways through which groundwater (including acid mine inflow) preferentially infiltrates and flows in acidic mines. These pathways typically include macroscopic fissures developed in the surrounding rock, through-flow fissures formed by mining, gaps between rock strata, and connecting channels in goaf areas. They are characterized by large inflow volume, fast flow velocity, and high efficiency of pollutant migration, and are the core target of grouting and sealing treatment.

[0012] The term "mining void" used in this article refers to the space occupied by the mined ore body left after the underground mineral resources have been mined during the mining process. It consists of pillars, surrounding rock and roof, and is prone to water accumulation, forming acidic mine water. Moreover, it contains a large number of fissures and voids, making it an important storage space and one of the advantageous recharge channels for acidic mine water.

[0013] To achieve the above objectives, the present invention provides the following technical solution: In a first aspect, the present invention provides: an acid-resistant sealing grouting material suitable for the treatment of acidic mine water inrush, comprising nano-hydroxyapatite, sodium alginate, porous adsorbent material, cement, water glass, quicklime, retarder and water.

[0014] In some embodiments, the porous adsorbent is at least one selected from zeolite powder, bentonite, diatomaceous earth, molecular sieve, lignin, fly ash, and activated carbon. Bentonite, fly ash, and activated carbon are preferred. More preferably, the weight ratio of bentonite to fly ash is 1-5:3-8; even more preferably, it is 2:5.

[0015] In some embodiments, the retarder is citric acid and tartaric acid, preferably, the weight ratio of citric acid to tartaric acid is 1-5:1; more preferably 2-4:1.

[0016] In some embodiments, the acid-resistant sealing grouting material comprises, by weight: 8-12 parts nano-hydroxyapatite, 1.5-3 parts sodium alginate, 5-8 parts porous adsorbent material, 100 parts cement, 25-35 parts water glass, 3-5 parts quicklime, 0.5-1.0 parts retarder, and 50-65 parts water.

[0017] In some embodiments, the weight ratio of the nano-hydroxyapatite, sodium alginate, and porous adsorbent material is 8-12:1.5-3:5-8; preferably 9-11:2-3:5-7; and more preferably 10:2.5:6.

[0018] In some embodiments, the weight ratio of the nano-hydroxyapatite, cement, and retarder is 8-12:100:0.5-1.0; preferably 10:100:0.7.

[0019] In some embodiments, the acid-resistant sealing grouting material comprises, by weight: 10 parts nano-hydroxyapatite, 3 parts sodium alginate, 6 parts porous adsorbent material, 100 parts cement, 30 parts water glass, 4 parts quicklime, 0.7 parts retarder, and 60 parts water.

[0020] Secondly, the present invention provides a method for preparing the above-mentioned acid-resistant sealing grouting material, comprising the following steps: (1) Sodium alginate was dissolved in water to obtain sodium alginate sol. (2) Add nano-hydroxyapatite and porous adsorbent to sodium alginate sol, mix and homogenize to obtain composite slurry; (3) Add the amount of cement and the remaining water to the composite grout and stir evenly. Finally, add the amount of water glass, quicklime and retarder and stir evenly.

[0021] In some implementations, the homogenization in step (2) is carried out at 15-25 MPa, 1-3 times, for 3-5 minutes each time.

[0022] Thirdly, the present invention provides the application of the above-mentioned acid-resistant sealing grouting material in acidic mine water.

[0023] Fourthly, the present invention provides a method for treating acidic mine water, comprising the following steps: It includes source treatment of acidic mine inrush water, treatment during the flow process, and end-of-pipe treatment. The source treatment of acidic mine inrush water involves grouting and sealing the dominant channels of groundwater using the aforementioned acid-resistant sealing grouting material.

[0024] In some implementations, the grouting pressure is 0.5-3.0 MPa.

[0025] The beneficial effects of this invention are as follows: In the acid-resistant sealing grouting material of this invention, porous adsorption materials rapidly adsorb and fix iron and manganese ions through physical adsorption and ion exchange; sodium alginate further stabilizes metal ions through coordination complexation and three-dimensional gel encapsulation; nano-hydroxyapatite releases phosphate ions to generate insoluble phosphate precipitates, deeply stabilizing iron and manganese; quicklime neutralizes acidity and raises pH, promoting the precipitation of iron and manganese as hydroxides; the cement-water glass system rapidly gels, solidifying all products into a dense solid body, preventing acidic water from contacting the surrounding rock, controlling pollution at the source, and providing long-term sealing.

[0026] Compared with existing technologies, the acid-resistant sealing grouting material of the present invention can immobilize iron and manganese, has strong acid resistance and good pressure resistance, and is suitable for grouting materials for sealing goaf areas and fissures in closed mines. Detailed Implementation

[0027] The following non-limiting embodiments are intended to enable those skilled in the art to gain a more comprehensive understanding of the present invention, but do not limit the invention in any way. The following content is merely an exemplary description of the scope of protection claimed by the present invention, and those skilled in the art can make various changes and modifications to the present invention based on the disclosed content, and such changes should also fall within the scope of protection claimed by the present invention.

[0028] The present invention will be further described below by way of specific embodiments. All instruments, devices, equipment, reagents, products, etc., used in the embodiments of the present invention were obtained through conventional commercial channels unless otherwise specified. Nano-hydroxyapatite, CAS: 1306-096-5, was purchased from Qianyan Chemical Technology (Wuhan) Co., Ltd.; bentonite was purchased from Sishui Shengxin Refractory Materials Co., Ltd., item number 1524554, particle size 300 mesh, density 2.6 g / cm³. 3 Fly ash (Grade 1 fly ash), particle size 45μm, purchased from Shuangshi Mineral Processing Plant, Lingshou County; cement is sulfoaluminate cement, grade 52.5; water glass, Baume degree 30-46, effective ingredient 40%, purchased from Chongqing Junheng Chemical Co., Ltd.; the mixing was carried out at 500rpm for 15min.

[0029] Example 1 An acid-resistant sealing grouting material suitable for treating acidic mine water inrush The formula by weight is as follows: 10 parts nano hydroxyapatite, 2.5 parts sodium alginate, 6 parts porous adsorbent material, 100 parts cement, 30 parts water glass, 4 parts quicklime, 0.7 parts retarder and 60 parts water. The porous adsorbent material is bentonite and fly ash in a weight ratio of 2:5. The retarder is citric acid and tartaric acid in a weight ratio of 3:1.

[0030] The preparation method is as follows: (1) Sodium alginate in the formula amount is swollen by adding 1 / 2 of the formula amount of water to obtain sodium alginate sol; (2) Add the formulated amount of nano-hydroxyapatite and porous adsorbent to the sodium alginate sol and mix. Homogenize twice at 20 MPa for 4 min each time to obtain a composite slurry. (3) Add the amount of cement and the remaining water to the composite grout and stir evenly. Finally, add the amount of water glass, quicklime and retarder and stir evenly.

[0031] Example 2 An acid-resistant sealing grouting material suitable for treating acidic mine water inrush The formula by weight is as follows: 8 parts nano hydroxyapatite, 1.5 parts sodium alginate, 5 parts porous adsorbent material, 100 parts cement, 25 parts water glass, 3 parts quicklime, 0.5 parts retarder and 50 parts water. The porous adsorbent material is bentonite and fly ash in a weight ratio of 1:3. The retarder is citric acid and tartaric acid in a weight ratio of 1:1.

[0032] The preparation method is as follows: (1) Sodium alginate in the formula amount is swollen by adding 1 / 2 of the formula amount of water to obtain sodium alginate sol; (2) Add the formulated amount of nano-hydroxyapatite and porous adsorbent to the sodium alginate sol and mix. Homogenize at 15 MPa for 3 times, 3 min each time, to obtain a composite slurry. (3) Add the amount of cement and the remaining water to the composite grout and stir evenly. Finally, add the amount of water glass, quicklime and retarder and stir evenly.

[0033] Example 3 An acid-resistant sealing grouting material suitable for treating acidic mine water inrush The formula by weight is as follows: 12 parts nano hydroxyapatite, 3 parts sodium alginate, 8 parts porous adsorbent material, 100 parts cement, 35 parts water glass, 5 parts quicklime, 1 part retarder and 65 parts water. Among them, the porous adsorbent material is bentonite and fly ash in a weight ratio of 5:8; The retarder is citric acid and tartaric acid in a weight ratio of 5:1.

[0034] The preparation method is as follows: (1) Sodium alginate in the formula amount is swollen by adding 1 / 2 of the formula amount of water to obtain sodium alginate sol; (2) Add the formulated amount of nano-hydroxyapatite and porous adsorbent to the sodium alginate sol and mix. Homogenize once at 25 MPa for 5 min each time to obtain a composite slurry. (3) Add the amount of cement and the remaining water to the composite grout and stir evenly. Finally, add the amount of water glass, quicklime and retarder and stir evenly.

[0035] Comparative Example 1 The difference between this comparative example and Example 1 is that the weight ratio of nano-hydroxyapatite, sodium alginate, and porous adsorbent material is different.

[0036] Specifically, an acid-resistant sealing grouting material suitable for treating acidic mine water inrush has the following formula by weight: 6 parts nano hydroxyapatite, 0.5 parts sodium alginate, 12 parts porous adsorption material, 100 parts cement, 30 parts water glass, 4 parts quicklime, 0.7 parts retarder and 60 parts water. The porous adsorbent material is bentonite and fly ash in a weight ratio of 2:5. The retarder is citric acid and tartaric acid in a weight ratio of 3:1.

[0037] The preparation method is the same as in Example 1.

[0038] Comparative Example 2 The difference between this comparative example and Example 1 is that the weight ratio of nano-hydroxyapatite, sodium alginate, and porous adsorbent material is different.

[0039] Specifically, an acid-resistant sealing grouting material suitable for treating acidic mine water inrush has the following formula by weight: 14 parts nano hydroxyapatite, 2.5 parts sodium alginate, 2 parts porous adsorbent material, 100 parts cement, 30 parts water glass, 4 parts quicklime, 0.7 parts retarder and 60 parts water. The porous adsorbent material is bentonite and fly ash in a weight ratio of 2:5. The retarder is citric acid and tartaric acid in a weight ratio of 3:1.

[0040] The preparation method is the same as in Example 1.

[0041] Comparative Example 3 The difference between this comparative example and Example 1 is that the porous adsorbent material is bentonite.

[0042] Specifically, an acid-resistant sealing grouting material suitable for treating acidic mine water inrush. The formula by weight is as follows: 10 parts nano hydroxyapatite, 2.5 parts sodium alginate, 6 parts porous adsorbent material, 100 parts cement, 30 parts water glass, 4 parts quicklime, 0.7 parts retarder and 60 parts water. Among them, the porous adsorbent material is bentonite; The retarder is citric acid and tartaric acid in a weight ratio of 3:1.

[0043] The preparation method is the same as in Example 1.

[0044] Comparative Example 4 The difference between this comparative example and Example 1 is that the porous adsorbent material is fly ash.

[0045] Specifically, an acid-resistant sealing grouting material suitable for treating acidic mine water inrush. The formula by weight is as follows: 10 parts nano hydroxyapatite, 2.5 parts sodium alginate, 6 parts porous adsorbent material, 100 parts cement, 30 parts water glass, 4 parts quicklime, 0.7 parts retarder and 60 parts water. Among them, the porous adsorbent material is fly ash; The retarder is citric acid and tartaric acid in a weight ratio of 3:1.

[0046] The preparation method is the same as in Example 1.

[0047] Comparative Example 5 The difference between this comparative example and Example 1 is that the preparation method uses stirring to replace the homogenization step.

[0048] Everything else is the same as in Example 1.

[0049] Example 1: Test of acid-resistant sealing grouting material on Fe in acidic mine water 3+ Mn 2+ Removal effect Take a simulated acidic mine water solution (pH=3.0, Fe...) 3+ =100mg / L, Mn 2+ =20mg / L, SO4 2- =1500mg / L), added to the acid-resistant sealing grouting material prepared in the examples or comparative examples at a weight ratio of 20:1, shaken at 25℃ and 150r / min for 60min, allowed to stand and filtered, and the supernatant was used to determine the Fe content using an atomic absorption spectrophotometer. 3+ Mn 2+ Concentration, the removal rate is calculated using the following formula: Removal rate (%) = (initial ion concentration - final ion concentration) × 100% / initial ion concentration.

[0050] The results are shown in Table 1.

[0051] Table 1

[0052] The results showed that the acid-resistant sealing grouting materials prepared in Examples 1-3 of this invention effectively resisted the Fe in acidic mine water. 3+ Mn 2 + It has excellent removal effects, reaching 95.3%-97.5% and 91.7%-93.8% respectively.

[0053] Comparison of Examples 1-2 shows that the acid-resistant sealing material prepared by combining nano-hydroxyapatite, sodium alginate, and porous adsorbent materials in a conventional weight ratio exhibits better resistance to Fe. 3+ Mn 2+ The removal effect was poor, not exceeding 80%; at the same time, comparison with Comparative Examples 3-4 showed that the acid-resistant sealing and plugging materials prepared using bentonite or fly ash as the sole porous adsorbent material had a poor effect on Fe. 3+ Mn 2+ The removal effect was poor, not exceeding 85%, indicating that the present invention produced a synergistic effect through nano-hydroxyapatite, sodium alginate and specific porous adsorption materials, which can efficiently remove Fe ions and Mn ions in acidic mine water.

[0054] Detection Example 2 The acid-resistant sealing grouting materials prepared in the examples and comparative examples were injected into a standard mold and cured for 24 hours at 20°C and ≥90% humidity before demolding. After further curing for 3 days, standard samples were obtained. These standard samples were then subjected to acidic mine water simulation solution (pH=3.0, Fe) at 30°C. 3+ =100mg / L, Mn 2+ =20mg / L, SO4 2- After soaking in 1500mg / L solution for 30 days, the solution was removed, rinsed with water, and then subjected to a pressure test using a QD-2 type leak-stopping instrument (seam length 30mm, width 1mm). The test temperature was 20℃, and the maximum pressure at which the leak-stopping layer did not leak or crack was taken as the pressure resistance (MPa). The results are shown in Table 2.

[0055] Table 2

[0056] The results show that the acid-resistant sealing grouting materials prepared in Examples 1-3 of this invention have high initial compressive strength and no significant strength decay after being soaked in acidic mine water for 30 days, demonstrating excellent acid resistance and structural stability.

[0057] The acid-resistant sealing grouting material prepared in comparison showed a significant decrease in strength after being soaked in acidic mine water for 30 days.

[0058] Finally, it should be noted that the above content is only used to illustrate the technical solution of the present invention, and is not intended to limit the scope of protection of the present invention. Simple modifications or equivalent substitutions made by those skilled in the art to the technical solution of the present invention do not depart from the essence and scope of the technical solution of the present invention.

Claims

1. An acid-resistant plugging and grouting material suitable for the treatment of acid mine water, characterized in that, By weight, it includes: 8-12 parts nano hydroxyapatite, 1.5-3 parts sodium alginate, 5-8 parts porous adsorbent material, 100 parts cement, 25-35 parts water glass, 3-5 parts quicklime, 0.5-1.0 parts retarder and 50-65 parts water.

2. Acid-resistant plugging and grouting material according to claim 1, characterized in that The porous adsorbent material is at least one of zeolite powder, bentonite, diatomaceous earth, molecular sieve, lignin, fly ash, and activated carbon.

3. Acid-resistant plugging and grouting material according to claim 1, characterized in that The porous adsorbent material is bentonite and fly ash; the retarder is citric acid and tartaric acid.

4. Acid-resistant plugging and grouting material according to claim 3, characterized in that The weight ratio of bentonite to fly ash is 1-5:3-8; the weight ratio of citric acid to tartaric acid is 1-5:

1.

5. The acid-resistant sealing grouting material according to claim 1, characterized in that, The weight ratio of the nano-hydroxyapatite, sodium alginate, and porous adsorbent material is 8-12:1.5-4:5-8.

6. The acid-resistant sealing grouting material according to claim 1, characterized in that, The weight ratio of the nano-hydroxyapatite, cement, and retarder is 8-12:100:0.5-1.

0.

7. The method for preparing the acid-resistant sealing grouting material according to any one of claims 1-6, characterized in that, Includes the following steps: (1) Sodium alginate was dissolved in water to obtain sodium alginate sol. (2) Add nano-hydroxyapatite and porous adsorbent to sodium alginate sol, mix and homogenize to obtain composite slurry; (3) Add the amount of cement and the remaining water to the composite grout and stir evenly. Finally, add the amount of water glass, quicklime and retarder and stir evenly.

8. The preparation method according to claim 7, characterized in that, The homogenization in step (2) is carried out at 15-25 MPa, 1-3 times, 3-5 minutes each time.

9. The application of the acid-resistant sealing grouting material according to any one of claims 1-6 or the acid-resistant sealing grouting material prepared by the preparation method according to any one of claims 7-8 in acidic mine water.

10. A method for treating acidic mine inrush water, comprising the following steps: source treatment of the acidic mine inrush water, process treatment during flow, and end-of-pipe treatment, characterized in that, The treatment of the acidic mine water source involves grouting and sealing the dominant underground water channels using the acid-resistant sealing grouting material described in any one of claims 1-6 or the acid-resistant sealing grouting material prepared by the preparation method described in any one of claims 7-8.

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