Water-erosion-resistant high-hardness mining dust suppressant based on multi-crosslinking and preparation method of water-erosion-resistant high-hardness mining dust suppressant

Abstract

The invention discloses a multi-crosslinking-based water-erosion-resistant high-hardness mining dust suppressant and a preparation method thereof.The dust suppressant is prepared from, by weight, 2-5 parts of plant polysaccharide, 4-10 parts of an oxidizing agent, 1-10 parts of protein, 10-20 parts of acrylic acid, 0.1-0.5 part of an initiator, 3-8 parts of a wetting agent and the balance solvent. Through a multi-cross-linked network formed through covalent bond-hydrogen bond synergistic effect, the hardness, water erosion resistance and water retention of a consolidation layer of the dust suppressant are remarkably improved, the dust suppression efficiency is high, the material is biodegradable, the problems that a traditional dust suppressant is poor in weather resistance, secondary dust raising is likely to be caused, and environmental compatibility is insufficient can be effectively solved, and the dust suppressant is suitable for industrial production. The method is suitable for dust treatment in the scenes of mining, transportation, stockpiling and the like, and has good social and economic benefits.

Description

Technical Field

[0001] This invention relates to the field of dust control technology, specifically to a water-resistant, high-hardness mining dust suppressant based on multiple cross-linking and its preparation method. Background Technology

[0002] As a major coal producer and consumer, my country faces severe dust pollution problems during coal mining, transportation, and storage, despite the significant economic benefits it brings. Dust pollution generated during these processes poses a serious threat to safe production, miners' occupational health, and the ecological environment. When the concentration of dust floating in the air at the working face and in roadways reaches the explosive limit, it can cause a mine dust explosion upon contact with an open flame, resulting in a wide-ranging and destructive event that causes severe casualties and property damage. Current dust suppression technologies mainly include traditional methods such as ventilation dust removal, coal seam water injection, spray dust suppression, and dust collectors. However, these methods suffer from bottlenecks such as high water consumption, short suppression cycles, low efficiency, and high costs associated with repetitive operations. While chemical dust suppressants can extend their effectiveness, they generally suffer from limited dust suppression capabilities, poor weather resistance, low hardness of the coal dust consolidation layer, and easy disintegration upon rainwater erosion, leading to secondary dust pollution. Furthermore, chemical dust suppressants have poor biodegradability, and long-term use can easily lead to soil compaction and the accumulation of ecotoxicity, posing environmental risks.

[0003] Although existing studies have attempted to improve performance through compound modification, a single cross-linking mechanism still cannot synergistically resolve the contradiction between high-strength consolidation, long-term water erosion resistance, and environmental compatibility. Especially in open environments such as open mines, there is an urgent need for a new type of dust suppression material that can combine high coal dust consolidation strength, good rainwater erosion resistance, excellent water retention, high dust suppression efficiency, and good degradability, fundamentally overcoming the limitations of existing technologies in adapting to multiple environmental stresses. Summary of the Invention

[0004] To address the technical problems of existing dust suppressants, such as poor water erosion resistance, insufficient water retention, and low hardness of the consolidated layer, this invention discloses a water-erosion resistant, high-hardness mining dust suppressant based on multiple crosslinking and its preparation method.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a water-resistant, high-hardness mining dust suppressant based on multiple cross-linking, wherein the raw materials for preparation, by weight percentage, include:

[0006] 2-5 parts plant polysaccharide, 4-10 parts oxidant, 1-10 parts protein, 10-20 parts acrylic acid, 0.1-0.5 parts initiator, 3-8 parts wetting agent, and the remainder is solvent.

[0007] Preferably, the plant polysaccharide is tarara gum.

[0008] Preferably, sodium periodate is used as the oxidant.

[0009] Preferably, casein is selected as the protein.

[0010] Preferably, ammonium persulfate is selected as the initiator.

[0011] Preferably, the wetting agent is an anionic surfactant, and more preferably sodium fatty alcohol polyoxyethylene ether sulfate.

[0012] Preferably, distilled water is used as the solvent. Under the condition of 100mL distilled water, the weights of each raw material are as follows: 0.3g tara gum, 0.5g sodium periodate, 0.6g casein, 1.5g acrylic acid, 0.01g ammonium persulfate, and 0.5g sodium fatty alcohol polyoxyethylene ether sulfate.

[0013] This invention also proposes a method for preparing a water-erosion-resistant, high-hardness mining dust suppressant based on multiple crosslinking, as mentioned above, comprising the following steps:

[0014] S1. Dissolve tara gum in distilled water until completely dissolved to obtain a tara gum aqueous solution;

[0015] S2. Add sodium periodate to the Tara gum aqueous solution, adjust the pH, and then react to obtain an oxidized Tara gum aqueous solution.

[0016] S3. Adjust the pH of the oxidized taraxacin aqueous solution, add casein and react to obtain the modified product I aqueous solution.

[0017] S4. Dissolve acrylic acid in distilled water and add ammonium persulfate to react and obtain an aqueous solution of polyacrylic acid.

[0018] S5. The obtained polyacrylic acid aqueous solution and modified product I aqueous solution are mixed and reacted to obtain modified product II aqueous solution.

[0019] S6. After adjusting the aqueous solution of modified product II to neutral, add sodium fatty alcohol polyoxyethylene ether sulfate and stir at room temperature until dissolved to finally obtain the dust suppressant solution.

[0020] Preferably, in S2, the pH is adjusted to 4, the reaction temperature is 60℃, and the reaction time is 2h. A pH that is too low (<4) will cause the reaction to be too vigorous, leading to excessive oxidation of tara gum, destroying its structure and producing byproducts. A pH that is too high (>4) will significantly reduce the oxidation efficiency due to the reduction of the active form of periodic acid, resulting in a sharp decrease in the reaction rate. At the same time, the aldehyde groups generated by oxidation are prone to side reactions in an alkaline environment, leading to a decrease in product stability. In S3, the pH is adjusted to 10, the reaction temperature is 75-90℃, and the reaction time is 2h. The temperature of 75-90℃ is high enough to accelerate molecular collisions, promote protein unfolding and polysaccharide dissolution, and drive dehydration and bonding. At the same time, it avoids excessive protein aggregation, polysaccharide degradation, exacerbation of Maillard side reactions, and product hydrolysis caused by excessively high temperatures. In S4, the reaction temperature is 60℃ and the reaction time is 1h. In S5, the reaction temperature is 60℃ and the reaction time is 2h.

[0021] Preferably, the solutions used to adjust the pH are 3% dilute hydrochloric acid and 5% sodium hydroxide.

[0022] The raw materials selected for preparing water-erosion-resistant, high-hardness dust suppressants have the following characteristics:

[0023] Tara gum is the endosperm of *Ligustrum lucidum* seeds. It is a natural plant polysaccharide that is completely biodegradable by microorganisms and is non-toxic and harmless to soil, water, plants, animals, and humans. Tara gum has excellent adhesive properties and is often used as an adhesive to effectively bind dust particles together. Simultaneously, tara gum has excellent water retention properties, which can effectively reduce the cracking of dust suppression films due to drying and extend the dust suppression time of the dust suppressant.

[0024] Casein is the most abundant protein in milk. It is inexpensive, readily available, non-toxic, and easily biodegradable. Casein possesses a unique spatial structure with numerous hydrogen and hydrophobic bonds, along with excellent emulsifying and heat-resistant properties, giving it outstanding film-forming characteristics. It can effectively coat dust surfaces, forming a dense dust-suppressing film. Furthermore, casein contains a large number of amino groups that can react with carbonyl groups for modification.

[0025] Polyacrylic acid is a high molecular compound polymerized from acrylic acid monomers. Its molecular structure contains a large number of hydrophilic carboxyl groups, which have excellent water retention properties and can be used as a water-retaining agent. At the same time, the large number of carboxyl groups in polyacrylic acid makes it easy to crosslink with other dust suppression materials, thereby enhancing the mechanical properties of dust suppression materials.

[0026] Sodium periodate is a commonly used oxidizing agent in laboratories and industries due to its strong oxidizing power and wide applicability.

[0027] Sodium fatty alcohol polyoxyethylene ether sulfate is an anionic surfactant with excellent wetting properties and low irritation to human skin. It can be used in detergents such as laundry liquid, laundry powder, and dishwashing detergent, and its biodegradability is greater than 80%.

[0028] The reaction equation of this invention is as follows:

[0029]

[0030] Reaction principle:

[0031] Tara gum molecules contain a large number of hydroxyl groups (-OH). The hydroxyl groups on carbons 2, 3, and 4 of the repeating units in the tara gum molecule are oxidized by sodium periodate. Through the cleavage of carbon-carbon bonds, two aldehyde groups (-CHO) are formed on each oxidized monomer unit, which can then undergo a Schiff base reaction with casein. Casein has abundant amino groups (-NH2), which are nucleophilic and can attack the aldehyde groups (-CHO) on the oxidized tara gum to carry out an addition reaction, forming an unstable intermediate with hydroxyl groups. The intermediate is unstable and, after a dehydration reaction, eventually forms an imine bond (-C=N).

[0032] The highly reactive SO4- radicals generated by the thermal decomposition of ammonium persulfate, a strong oxidant, can initiate free radical polymerization of acrylic acid to generate long polyacrylic acid chains. The numerous carboxyl groups (-COOH) in the long polyacrylic acid chains crosslink with the hydroxyl groups (-OH) in modified product I through hydrogen bonds, causing the molecular chains to entangle with each other and ultimately forming a multi-layered crosslinked network structure.

[0033] Compared with the prior art, the present invention provides a water-erosion-resistant, high-hardness mining dust suppressant based on multiple cross-linking and its preparation method, which has the following beneficial effects:

[0034] (1) This invention modifies the hydroxyl groups in Tara gum to aldehyde groups through oxidation modification, enabling them to undergo Schiff base reactions with the amino groups in casein to form imine bonds, thus constructing a covalent cross-linked network. This enhances the toughness and mechanical properties of the dust suppression film, making it better resistant to rainwater erosion. Simultaneously, cross-linking casein with polysaccharides in Tara gum effectively improves the problems of low casein solubility and easy precipitation, making the dust suppressant solution easier to spray.

[0035] (2) Acrylic acid is polymerized into long polyacrylic acid chains by ammonium persulfate, which can be cross-linked and wrapped in tara gum-casein molecules through hydrogen bonds to form a three-dimensional cross-linked network, thereby improving the mechanical properties of the dust suppressant. Polyacrylic acid contains abundant carboxyl groups, which gives it excellent water retention. The introduction of polyacrylic acid enhances the water retention of the dust suppressant and improves the problem of secondary dust generation caused by drying and cracking of the cured layer of the dust suppressant.

[0036] (3) The aldehyde groups (-CHO) generated by the oxidation of tara gum form Schiff base covalent bonds (-C=N) with the amino groups (-NH2) of casein, while the carboxyl groups (-COOH) of polyacrylic acid and the hydroxyl groups (-OH) of casein-tara gum form a hydrogen bond network. Combined with the hydrophobic interaction of casein, a multi-crosslinked system of covalent bonds and hydrogen bonds is formed. This structure significantly improves the mechanical strength and water erosion resistance of dust suppressants, and improves the problems of low hardness and easy disintegration of the consolidation layer of traditional dust suppressants when exposed to water.

[0037] (4) The dust suppressant prepared in this invention has readily available raw materials, good degradability, and excellent water retention. It also exhibits high hardness of the solidified layer, good water erosion resistance, and high dust suppression efficiency. The addition of materials such as Tara gum gives the dust suppressant excellent adhesion properties. After spraying, it effectively binds dust particles and forms a solidified layer on the coal dust surface, effectively suppressing dust dispersion. Simultaneously, the dust suppressant forms a high-strength solidified layer with both rigidity and toughness through a multi-linked network, significantly improving the hardness and water erosion resistance of the solidified layer. This achieves efficient dust suppression in different scenarios, resulting in significant social and economic benefits. Attached Figure Description

[0038] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used together with the embodiments of the invention to explain the invention, but do not constitute a limitation thereof. In the drawings:

[0039] Figure 1 This is a schematic diagram of the process flow of the present invention;

[0040] Figure 2 This is a comparison chart of the water loss rate of the dust suppressants prepared in various embodiments of the present invention during the water retention test;

[0041] Figure 3 The figure shows the experimental results of dust suppression efficiency tests of the dust suppressants prepared in various embodiments of the present invention. Detailed Implementation

[0042] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0043] Example 1

[0044] (1) Add 50 mL of distilled water to a beaker, dissolve 0.2 g of tara gum in the distilled water, place it in a magnetic stirring water bath, set the temperature to 75℃, stir at 350 r / min for 1 h until the tara gum is completely dissolved, and obtain a tara gum aqueous solution.

[0045] (2) Raise the water bath temperature to 60°C, add 0.5g of sodium periodate to the Tara gum aqueous solution, add dilute hydrochloric acid (3%) to adjust the pH to 4, and heat and stir at 300r / min for 2h to obtain oxidized Tara gum aqueous solution.

[0046] (3) Add sodium hydroxide (5%) to the oxidized tarara aqueous solution, adjust the pH to 10, and stir evenly on a magnetic stirrer; then add 0.2g of casein, and stir magnetically at 300r / min at 80℃ for 2h to obtain the modified product I aqueous solution.

[0047] (4) Take another beaker, add 50 mL of distilled water, dissolve 1 g of acrylic acid in the distilled water, add 0.01 g of ammonium persulfate, place the beaker in a water bath at 60 °C and react for 1 h to obtain an aqueous solution of polyacrylic acid.

[0048] (5) Slowly pour the polyacrylic acid aqueous solution into the beaker containing the modified product I solution and stir with a magnetic stirrer until uniform. Place the mixed solution in a water bath at 60°C and react for 2 hours to obtain the modified product II aqueous solution.

[0049] (6) After adjusting the aqueous solution of modified product II to neutral, add 0.5g of sodium fatty alcohol polyoxyethylene ether sulfate and stir until dissolved at room temperature to finally obtain the dust suppressant solution.

[0050] Example 2

[0051] (1) Add 50 mL of distilled water to a beaker, dissolve 0.2 g of tara gum in the distilled water, place it in a magnetic stirring water bath, set the temperature to 75℃, stir at 350 r / min for 1 h until the tara gum is completely dissolved, and obtain a tara gum aqueous solution.

[0052] (2) Raise the water bath temperature to 60°C, add 0.5g of sodium periodate to the Tara gum aqueous solution, add dilute hydrochloric acid (3%) to adjust the pH to 4, and heat and stir at 300r / min for 2h to obtain oxidized Tara gum aqueous solution.

[0053] (3) Add sodium hydroxide (5%) to the oxidized tarara aqueous solution, adjust the pH to 10, and stir evenly on a magnetic stirrer; then add 0.4g of casein, and stir magnetically at 300r / min at 85℃ for 2h to obtain the modified product I aqueous solution.

[0054] (4) Take another beaker, add 50 mL of distilled water, dissolve 1.5 g of acrylic acid in the distilled water, add 0.01 g of ammonium persulfate, place the beaker in a water bath at 60 °C and react for 1 h to obtain an aqueous solution of polyacrylic acid.

[0055] (5) Slowly pour the polyacrylic acid aqueous solution into the beaker containing the modified product I solution and stir with a magnetic stirrer until uniform. Place the mixed solution in a water bath at 60°C and react for 2 hours to obtain the modified product II aqueous solution.

[0056] (6) After adjusting the aqueous solution of modified product II to neutral, add 0.5g of sodium fatty alcohol polyoxyethylene ether sulfate and stir until dissolved at room temperature to finally obtain the dust suppressant solution.

[0057] Example 3

[0058] (1) Add 50 mL of distilled water to a beaker, dissolve 0.2 g of tara gum in the distilled water, place it in a magnetic stirring water bath, set the temperature to 75℃, stir at 350 r / min for 1 h until the tara gum is completely dissolved, and obtain a tara gum aqueous solution.

[0059] (2) Raise the water bath temperature to 60°C, add 0.5g of sodium periodate to the Tara gum aqueous solution, add dilute hydrochloric acid (3%) to adjust the pH to 4, and heat and stir at 300r / min for 2h to obtain oxidized Tara gum aqueous solution.

[0060] (3) Add sodium hydroxide (5%) to the oxidized tarara aqueous solution, adjust the pH to 10, and stir evenly on a magnetic stirrer; then add 0.1g of casein, and stir magnetically at 300r / min at 90℃ for 2h to obtain the modified product I aqueous solution.

[0061] (4) Take another beaker, add 50 mL of distilled water, dissolve 2 g of acrylic acid in the distilled water, add 0.01 g of ammonium persulfate, place the beaker in a water bath at 60 °C and react for 1 h to obtain an aqueous solution of polyacrylic acid.

[0062] (5) Slowly pour the polyacrylic acid aqueous solution into the beaker containing the modified product I solution and stir with a magnetic stirrer until uniform. Place the mixed solution in a water bath at 60°C and react for 2 hours to obtain the modified product II aqueous solution.

[0063] (6) After adjusting the aqueous solution of modified product II to neutral, add 0.5g of sodium fatty alcohol polyoxyethylene ether sulfate and stir until dissolved at room temperature to finally obtain the dust suppressant solution.

[0064] Example 4

[0065] (1) Add 50 mL of distilled water to a beaker, dissolve 0.3 g of tara gum in the distilled water, place it in a magnetic stirring water bath, set the temperature to 75℃, stir at 350 r / min for 1 h until the tara gum is completely dissolved, and obtain a tara gum aqueous solution.

[0066] (2) Raise the water bath temperature to 60°C, add 0.5g of sodium periodate to the Tara gum aqueous solution, add dilute hydrochloric acid (3%) to adjust the pH to 4, and heat and stir at 300r / min for 2h to obtain oxidized Tara gum aqueous solution.

[0067] (3) Add sodium hydroxide (5%) to the taraxer aqueous solution, adjust the pH to 10, and stir evenly on a magnetic stirrer; then add 0.3g of casein, and stir magnetically at 300r / min at 90℃ for 2h to obtain the modified product I aqueous solution.

[0068] (4) Take another beaker, add 50 mL of distilled water, dissolve 1.5 g of acrylic acid in the distilled water, add 0.01 g of ammonium persulfate, place the beaker in a water bath at 60 °C and react for 1 h to obtain an aqueous solution of polyacrylic acid.

[0069] (5) Slowly pour the polyacrylic acid aqueous solution into the beaker containing the modified product I solution and stir with a magnetic stirrer until uniform. Place the mixed solution in a water bath at 60°C and react for 2 hours to obtain the modified product II aqueous solution.

[0070] (6) After adjusting the aqueous solution of modified product II to neutral, add 0.5g of sodium fatty alcohol polyoxyethylene ether sulfate and stir until dissolved at room temperature to finally obtain the dust suppressant solution.

[0071] Example 5

[0072] (1) Add 50 mL of distilled water to a beaker, dissolve 0.3 g of tara gum in the distilled water, place it in a magnetic stirring water bath, set the temperature to 75℃, stir at 350 r / min for 1 h until the tara gum is completely dissolved, and obtain a tara gum aqueous solution.

[0073] (2) Raise the water bath temperature to 60°C, add 0.5g of sodium periodate to the Tara gum aqueous solution, add dilute hydrochloric acid (3%) to adjust the pH to 4, and heat and stir at 300r / min for 2h to obtain oxidized Tara gum aqueous solution.

[0074] (3) Add sodium hydroxide (5%) to the oxidized tarara aqueous solution, adjust the pH to 10, and stir evenly on a magnetic stirrer; then add 0.6g of casein, and stir magnetically at 300r / min at 80℃ for 2h to obtain the modified product I aqueous solution.

[0075] (4) Take another beaker, add 50 mL of distilled water, dissolve 2 g of acrylic acid in the distilled water, add 0.01 g of ammonium persulfate, place the beaker in a water bath at 60 °C and react for 1 h to obtain an aqueous solution of polyacrylic acid.

[0076] (5) Slowly pour the polyacrylic acid aqueous solution into the beaker containing the modified product I solution and stir with a magnetic stirrer until uniform. Place the mixed solution in a water bath at 60°C and react for 2 hours to obtain the modified product II aqueous solution.

[0077] (6) After adjusting the aqueous solution of modified product II to neutral, add 0.5g of sodium fatty alcohol polyoxyethylene ether sulfate and stir until dissolved at room temperature to finally obtain the dust suppressant solution.

[0078] Example 6

[0079] (1) Add 50 mL of distilled water to a beaker, dissolve 0.3 g of tara gum in the distilled water, place it in a magnetic stirring water bath, set the temperature to 75℃, stir at 350 r / min for 1 h until the tara gum is completely dissolved, and obtain a tara gum aqueous solution.

[0080] (2) Raise the water bath temperature to 60°C, add 0.5g of sodium periodate to the Tara gum aqueous solution, add dilute hydrochloric acid (3%) to adjust the pH to 4, and heat and stir at 300r / min for 2h to obtain oxidized Tara gum aqueous solution.

[0081] (3) Add sodium hydroxide (5%) to the oxidized tarara aqueous solution, adjust the pH to 10, and stir evenly on a magnetic stirrer; then add 0.15g of casein, and stir magnetically at 300r / min at 85℃ for 2h to obtain the modified product I aqueous solution.

[0082] (4) Take another beaker, add 50 mL of distilled water, dissolve 1 g of acrylic acid in the distilled water, add 0.01 g of ammonium persulfate, place the beaker in a water bath at 60 °C and react for 1 h to obtain an aqueous solution of polyacrylic acid.

[0083] (5) Slowly pour the polyacrylic acid aqueous solution into the beaker containing the modified product I solution and stir with a magnetic stirrer until uniform. Place the mixed solution in a water bath at 60°C and react for 2 hours to obtain the modified product II aqueous solution.

[0084] (6) After adjusting the aqueous solution of modified product II to neutral, add 0.5g of sodium fatty alcohol polyoxyethylene ether sulfate and stir until dissolved at room temperature to finally obtain the dust suppressant solution.

[0085] Example 7

[0086] (1) Add 50 mL of distilled water to a beaker, dissolve 0.4 g of tara gum in the distilled water, place it in a magnetic stirring water bath, set the temperature to 75℃, stir at 350 r / min for 1 h until the tara gum is completely dissolved, and obtain a tara gum aqueous solution.

[0087] (2) Raise the water bath temperature to 60°C, add 0.5g of sodium periodate to the Tara gum aqueous solution, add dilute hydrochloric acid (3%) to adjust the pH to 4, and heat and stir at 300r / min for 2h to obtain oxidized Tara gum aqueous solution.

[0088] (3) Add sodium hydroxide (5%) to the oxidized tarara aqueous solution, adjust the pH to 10, and stir evenly on a magnetic stirrer; then add 0.4g of casein, and stir magnetically at 300r / min at 85℃ for 2h to obtain the modified product I aqueous solution.

[0089] (4) Take another beaker, add 50 mL of distilled water, dissolve 1.5 g of acrylic acid in the distilled water, add 0.01 g of ammonium persulfate, place the beaker in a water bath at 60 °C and react for 1 h to obtain an aqueous solution of polyacrylic acid.

[0090] (5) Slowly pour the polyacrylic acid aqueous solution into the beaker containing the modified product I solution and stir with a magnetic stirrer until uniform. Place the mixed solution in a water bath at 60°C and react for 2 hours to obtain the modified product II aqueous solution.

[0091] (6) After adjusting the aqueous solution of modified product II to neutral, add 0.5g of sodium fatty alcohol polyoxyethylene ether sulfate and stir until dissolved at room temperature to finally obtain the dust suppressant solution.

[0092] Example 8

[0093] (1) Add 50 mL of distilled water to a beaker, dissolve 0.4 g of tara gum in the distilled water, place it in a magnetic stirring water bath, set the temperature to 75℃, stir at 350 r / min for 1 h until the tara gum is completely dissolved, and obtain a tara gum aqueous solution.

[0094] (2) Raise the water bath temperature to 60°C, add 0.5g of sodium periodate to the Tara gum aqueous solution, add dilute hydrochloric acid (3%) to adjust the pH to 4, and heat and stir at 300r / min for 2h to obtain oxidized Tara gum aqueous solution.

[0095] (3) Add sodium hydroxide (5%) to the oxidized tarara aqueous solution, adjust the pH to 10, and stir evenly on a magnetic stirrer; then add 0.8g of casein, and stir magnetically at 300r / min at 90℃ for 2h to obtain the modified product I aqueous solution.

[0096] (4) Take another beaker, add 50 mL of distilled water, dissolve 1 g of acrylic acid in the distilled water, add 0.01 g of ammonium persulfate, place the beaker in a water bath at 60 °C and react for 1 h to obtain an aqueous solution of polyacrylic acid.

[0097] (5) Slowly pour the polyacrylic acid aqueous solution into the beaker containing the modified product I solution and stir with a magnetic stirrer until uniform. Place the mixed solution in a water bath at 60°C and react for 2 hours to obtain the modified product II aqueous solution.

[0098] (6) After adjusting the aqueous solution of modified product II to neutral, add 0.5g of sodium fatty alcohol polyoxyethylene ether sulfate and stir until dissolved at room temperature to finally obtain the dust suppressant solution.

[0099] Example 9

[0100] (1) Add 50 mL of distilled water to a beaker, dissolve 0.4 g of tara gum in the distilled water, place it in a magnetic stirring water bath, set the temperature to 75℃, stir at 350 r / min for 1 h until the tara gum is completely dissolved, and obtain a tara gum aqueous solution.

[0101] (2) Raise the water bath temperature to 60°C, add 0.5g of sodium periodate to the Tara gum aqueous solution, add dilute hydrochloric acid (3%) to adjust the pH to 4, and heat and stir at 300r / min for 2h to obtain oxidized Tara gum aqueous solution.

[0102] (3) Add sodium hydroxide (5%) to the oxidized tarara aqueous solution, adjust the pH to 10, and stir evenly on a magnetic stirrer; then add 0.2g of casein, and stir magnetically at 300r / min at 80℃ for 2h to obtain the modified product I aqueous solution.

[0103] (4) Take another beaker, add 50 mL of distilled water, dissolve 1.5 g of acrylic acid in the distilled water, add 0.01 g of ammonium persulfate, place the beaker in a water bath at 60 °C and react for 1 h to obtain an aqueous solution of polyacrylic acid.

[0104] (5) Slowly pour the polyacrylic acid aqueous solution into the beaker containing the modified product I solution and stir with a magnetic stirrer until uniform. Place the mixed solution in a water bath at 60°C and react for 2 hours to obtain the modified product II aqueous solution.

[0105] (6) After adjusting the aqueous solution of modified product II to neutral, add 0.5g of sodium fatty alcohol polyoxyethylene ether sulfate and stir until dissolved at room temperature to finally obtain the dust suppressant solution.

[0106] Comparative Example 1

[0107] Dissolve 0.3g of Tara gum in 100mL of distilled water and stir at 350r / min for 1h in a 75℃ water bath; then add 0.5g of sodium fatty alcohol polyoxyethylene ether sulfate and stir until dissolved at room temperature to obtain the material of Comparative Example 1.

[0108] Comparative Example 2

[0109] Dissolve 0.6 g of casein in 100 mL of distilled water and stir at 300 r / min for 1 h in a 75 °C water bath; then add 0.5 g of sodium fatty alcohol polyoxyethylene ether sulfate and stir until dissolved at room temperature to obtain the material of Comparative Example 2.

[0110] The present invention also tested the water retention, hardness of the consolidation layer, water erosion resistance, and dust suppression efficiency of the dust suppressants prepared in Examples 1-9 and Comparative Examples 1-2. The specific experiments are as follows:

[0111] Experiment 1 - Water retention and hardness test of the consolidation layer.

[0112] Test method: Weigh 5g of dried 200-mesh coal powder, make 11 portions, and place them in petri dishes. Add 20mL of the solutions prepared in Examples 1-9 and Comparative Examples 1-2 to each dish. Place the samples with added solutions in a vacuum drying oven at 60℃ for drying. Record the change in coal sample mass every hour for a total of 10 hours, and calculate the water loss rate.

[0113]

[0114] Where μ is the cumulative water loss rate of the sample, m0 is the initial sample weight (g), and m1 is the sample weight after drying (g).

[0115] Depend on Figure 2 As can be seen, Examples 1-9 all exhibited excellent water retention performance, retaining moisture even after evaporation at 60°C for 10 hours in a vacuum drying oven. Comparative Examples 1 and 2 showed faster water loss rates than Examples 1-9, and were completely dehydrated within approximately 7-8 hours. This is because the dust suppressant prepared in this invention uses hydrogen bonding to crosslink polyacrylic acid onto the dust suppressant molecules. Polyacrylic acid contains a large number of carboxyl groups, resulting in excellent water retention. Simultaneously, tara gum and casein, through covalent crosslinking, synergistically link the long chains of polyacrylic acid with hydrogen bonds, forming a three-dimensional crosslinked network that enhances the stability of the dust suppressant and further strengthens its water retention performance.

[0116] After the samples from Examples 1-9 and Comparative Examples 1-2 were completely dried, the hardness of the coal dust consolidation layer of different samples was measured using a Shore hardness tester. The test results are shown in Table 1.

[0117] Table 1. Results of Hardness Test of Consolidation Layer

[0118]

[0119] Table 1 shows that the hardness of the coal dust consolidation layer after drying in Examples 1-9 is above 75 HA, with a maximum of 87 HA. In contrast, the hardness of the consolidation layers in Comparative Examples 1 and 2 is only 53 HA and 46 HA, respectively. This indicates that the dust suppressant prepared in this invention can form a dense consolidation layer with good mechanical properties. This is because the casein molecules in the dust suppressant have excellent film-forming properties, which can form a consolidation layer on the coal seam surface. At the same time, the taraxer molecules and casein molecules undergo covalent cross-linking through Schiff base reaction, and the hydrogen bonds formed by the polyacrylic acid entanglement form a multi-cross-linking system with the covalent bonds, thereby improving the mechanical properties and hardness of the consolidation layer.

[0120] Experiment 2 - Water erosion resistance test.

[0121] The test method is as follows: Coal samples with the same initial mass are uniformly sprayed with equal masses of solutions from Examples 1-9 and Comparative Examples 1-2, and then placed in a 50℃ vacuum drying oven until completely dry. The mass at this point is recorded as m0. Spraying tests are then performed on materials sprayed with solutions from Examples 1-9 and Comparative Examples 1-2 for 2 minutes and 4 minutes respectively. After the test, the coal samples are again placed in a 50℃ vacuum drying oven until completely dry, and the mass at this point is recorded as m1. The water erosion resistance rate is calculated using the following formula:

[0122]

[0123] In the formula: μ is the water erosion resistance rate (%), m0 is the initial mass (g), and m1 is the mass after spraying (g).

[0124] The results of the water erosion resistance test are shown in Table 2:

[0125] Table 2 Results of water erosion resistance test

[0126]

[0127] As shown in Table 2, Examples 1-9 all had water erosion resistance rates of over 90% after spraying for 2 min and 4 min, while Comparative Examples 1 and 2 had water erosion resistance rates of only 43.69% and 41.53% after spraying for 4 min, respectively. This is because the dust suppressant prepared in this invention has excellent adhesion properties, which can cause dust to agglomerate and form a solidified layer on the coal seam surface. At the same time, since the dust suppressant prepared in this invention constructs a covalent bond-hydrogen bond multi-crosslinking system, it further improves the strength of the coal dust solidified layer, thus exhibiting better water erosion resistance.

[0128] Experiment 3 - Dust Suppression Efficiency Test

[0129] The test method is as follows: Equal amounts of coal powder are weighed and placed in petri dishes, then placed on a wind erosion simulation platform with a wind speed of 10 m / s. The dust suppression efficiency is determined through a wind erosion experiment. First, the initial concentrations C0 of PM2.5 and PM10 are detected using a handheld laser particle counter. Then, equal amounts of solutions from Examples 1-9 and Comparative Examples 1-2 are uniformly sprayed into the petri dishes, and placed in a constant temperature drying oven at 50°C until completely dry. The concentrations of PM2.5 and PM10 after spraying are detected again using a handheld laser particle counter and recorded as C1. The data are the average of three measurements. The dust suppression rate is calculated according to the following formula:

[0130]

[0131] In the formula, μ is the dust suppression rate (%), and C0 is the initial concentration of PM2.5 and PM10 (μg / m³). 3 C1 represents the concentrations of PM2.5 and PM10 after spraying the solution (μg / m³). 3 ).

[0132] Dust suppression efficiency test results are as follows Figure 3 As shown, through Figure 3 It can be concluded that the dust suppression efficiency of Examples 1-9 is significantly higher than that of Comparative Examples 1 and 2. The dust suppression efficiencies of PM10 and PM2.5 in Examples 1-9 are mostly above 95%. Therefore, the dust suppressant prepared by the present invention has good dust suppression properties, can effectively bind dust, and form a dense solidified layer on the dust surface, avoiding secondary dust generation caused by loose and sparse coal dust, and enhancing the dust suppression efficiency.

[0133] In summary, the water-resistant, high-hardness mining dust suppressant based on multiple cross-linking prepared in this invention possesses superior water retention, solidified layer hardness, water erosion resistance, and dust suppression efficiency. Spraying the dust suppressant prepared in this invention effectively binds dust and forms a high-strength solidified layer on the coal dust surface, efficiently resisting rainwater erosion and effectively preventing secondary dust generation. It improves upon the problems of poor rainwater erosion resistance, poor solidified layer strength, and low dust suppression efficiency of traditional dust suppressants, demonstrating significant social and economic benefits.

[0134] In the description of this invention, the terms "first," "second," "another," and "yet another" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, features defined as "first" or "second" may explicitly or implicitly include one or more features. In the description of embodiments of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0135] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "connected" and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances. Furthermore, in the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0136] Although embodiments of the invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A water-erosion-resistant, high-hardness dust suppressant for mining based on multiple cross-linking, characterized in that, The raw materials for preparation, by weight percentage, include: 2-5 parts plant polysaccharide, 4-10 parts oxidant, 1-10 parts protein, 10-20 parts acrylic acid, 0.1-0.5 parts initiator, 3-8 parts wetting agent, and the remainder is solvent.

2. The water-erosion-resistant, high-hardness mining dust suppressant based on multiple cross-linking as described in claim 1, characterized in that, The plant polysaccharide used is tarara gum.

3. The water-erosion-resistant, high-hardness mining dust suppressant based on multiple cross-linking as described in claim 2, characterized in that, Sodium periodate was chosen as the oxidant.

4. The water-erosion-resistant, high-hardness mining dust suppressant based on multiple cross-linking as described in claim 3, characterized in that, Casein was selected as the protein.

5. The water-erosion-resistant, high-hardness mining dust suppressant based on multiple crosslinking as described in claim 4, and its preparation method, characterized in that, Ammonium persulfate was chosen as the initiator.

6. The water-erosion-resistant, high-hardness mining dust suppressant based on multiple cross-linking as described in claim 5, characterized in that, The wetting agent is an anionic surfactant, preferably sodium fatty alcohol polyoxyethylene ether sulfate.

7. A water-erosion-resistant, high-hardness mining dust suppressant based on multiple cross-linking as described in claim 5, characterized in that, Distilled water was used as the solvent. Under 100mL of distilled water, the weights of each raw material were as follows: 0.3g tara gum, 0.5g sodium periodate, 0.6g casein, 1.5g acrylic acid, 0.01g ammonium persulfate, and 0.5g sodium fatty alcohol polyoxyethylene ether sulfate.

8. A method for preparing a water-erosion-resistant, high-hardness mining dust suppressant based on multiple crosslinking as described in claim 6 or 7, characterized in that, Includes the following steps: S1. Dissolve tara gum in distilled water until completely dissolved to obtain a tara gum aqueous solution; S2. Add sodium periodate to the Tara gum aqueous solution, adjust the pH, and then react to obtain an oxidized Tara gum aqueous solution. S3. Adjust the pH of the oxidized taraxacin aqueous solution, add casein and react to obtain the modified product I aqueous solution. S4. Dissolve acrylic acid in distilled water and add ammonium persulfate to react and obtain an aqueous solution of polyacrylic acid. S5. The obtained polyacrylic acid aqueous solution and modified product I aqueous solution are mixed and reacted to obtain modified product II aqueous solution. S6. After adjusting the aqueous solution of modified product II to neutral, add sodium fatty alcohol polyoxyethylene ether sulfate and stir at room temperature until dissolved to finally obtain the dust suppressant solution.

9. The preparation method of a water-erosion-resistant, high-hardness mining dust suppressant based on multiple cross-linking according to claim 8, characterized in that, In S2, the pH is adjusted to 4, the reaction temperature is 60℃, and the reaction time is 2 hours; in S3, the pH is adjusted to 10, the reaction temperature is 75-90℃, and the reaction time is 2 hours; in S4, the reaction temperature is 60℃, and the reaction time is 1 hour; in S5, the reaction temperature is 60℃, and the reaction time is 2 hours.

10. A water-erosion-resistant, high-hardness mining dust suppressant based on multiple crosslinking as described in claim 9, and its preparation method, characterized in that, The solutions used to adjust the pH were 3% dilute hydrochloric acid and 5% sodium hydroxide.

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