High-wettability and high-cohesiveness polysaccharide grafted foam dust-settling material as well as preparation method and application thereof

Abstract

The invention discloses a high-wetting and high-bonding polysaccharide grafted foam dust-settling material, which is characterized in that the foam dust-settling material is prepared from the following raw materials in parts by mass: 10 to 16 parts of bletilla striata polysaccharide, 8 to 12 parts of itaconic acid, 5 to 8 parts of trimethylolethane, 3 to 5 parts of diluted hydrochloric acid, 0.3 to 0.8 part of wetting agent, 2 to 4 parts of water-retaining agent and 100 to 300 parts of distilled water. The foam dust suppression material has a good foaming characteristic, and can rapidly wrap dust particles to achieve an effective dust suppression effect; the high-strength framework three-dimensional network with dynamic wettability and cohesiveness is achieved, the mechanical toughness and structural stability of the foam dust-settling material are remarkably improved, a formed dust consolidation layer can effectively resist erosion, and the defect that a traditional foam dust-settling material is prone to fragmentation is overcome.

Description

Technical Field

[0001] This invention relates to the field of dust control technology, specifically to a highly wettable, binding polysaccharide-grafted foam dust-suppressing material, its preparation method, and its application. Background Technology

[0002] Coal mining, as a crucial link in energy supply, has long faced the severe challenge of dust pollution. In underground operations, coal mining and transportation processes generate large amounts of fine dust. These extremely small particles possess strong suspension and diffusion properties, severely reducing visibility at the working face, affecting equipment operation, and posing a continuous threat to miners' health. Long-term exposure to high concentrations of dust can cause respiratory diseases and pneumoconiosis, and coal dust accumulation also carries the potential risk of explosions. Traditional dust suppression technologies, such as ordinary spray dust suppression, are limited by inherent defects such as high liquid surface tension and weak binding ability with hydrophobic coal dust, making it difficult to effectively capture and consolidate fine dust. Therefore, developing novel foam dust suppression materials that can efficiently penetrate the coal seam surface and achieve long-lasting adhesion has become an urgent need in the industry.

[0003] Foam dust suppression technology, due to its unique physical form, has shown significant advantages in the field of coal mine dust control. The porous network structure of foam can greatly increase the contact area between the dust suppression material and the dust, and its low surface tension gives it excellent wetting and spreading ability, enabling it to quickly encapsulate dust particles of different sizes. However, existing foam dust suppression materials generally suffer from insufficient mechanical strength and easy damage to the consolidated layer, making it difficult to meet the long-term dust suppression requirements under high-intensity mining conditions.

[0004] Therefore, there is an urgent need to develop a new type of foam dust suppression material with high bonding strength, which can maintain the inherent permeability advantage of foam while also having good dynamic wettability, adhesion, and high mechanical strength and stability of the consolidated layer, providing a breakthrough solution for complex mining environments. Summary of the Invention

[0005] To address the technical problems of poor wettability, poor adhesion, poor mechanical properties of the consolidated layer, and poor stability in existing dust suppression materials, this invention provides a highly wettable, adhesive polysaccharide-grafted foam dust suppression material, its preparation method, and its applications. This foam dust suppression material possesses excellent foaming properties, enabling it to rapidly encapsulate dust particles and achieve effective dust suppression. It also features a high-strength three-dimensional skeletal network with dynamic wettability and adhesion, significantly improving the mechanical toughness and structural stability of the foam dust suppression material. This allows the formed dust consolidation layer to effectively resist erosion, overcoming the fragility of traditional foam dust suppression materials.

[0006] The primary objective of this invention is to provide a highly wetting and binding polysaccharide-grafted foam dust-suppressing material, wherein the foam dust-suppressing material comprises the following raw materials in parts by weight: 10-16 parts of Bletilla striata polysaccharide, 8-12 parts of itaconic acid, 5-8 parts of trimethylol ethane, 3-5 parts of dilute hydrochloric acid, 0.3-0.8 parts of wetting agent, 2-4 parts of water-retaining agent, and 100-300 parts of distilled water.

[0007] Specifically, the wetting agent is Triton X-100; the water-retaining agent is glycerin; and the concentration of the dilute hydrochloric acid is 3%.

[0008] Specifically, when the amount of distilled water is 100 mL, the preferred weights of the other raw materials are: 15 g of Bletilla striata polysaccharide, 10.5 g of itaconic acid, 6.5 g of trimethylol ethane, 0.4 g of wetting agent and 1 g of water-retaining agent.

[0009] The second objective of this invention is to provide a method for preparing a highly wettable, binding polysaccharide-grafted foam dust-suppressing material, the method comprising the following steps:

[0010] S1. Distilled water and Bletilla striata polysaccharide are added to a beaker in sequence. The beaker is placed in a water bath and heated and stirred to completely dissolve the Bletilla striata polysaccharide in the distilled water, thus obtaining an aqueous solution of Bletilla striata polysaccharide.

[0011] S2 added itaconic acid to the aqueous solution of Bletilla striata polysaccharide to obtain a mixed solution; the pH of the mixed solution was adjusted to 4 with dilute hydrochloric acid and then an esterification grafting reaction was carried out to obtain grafted modified product I;

[0012] S3 adds distilled water and trimethylolethane to another beaker in sequence, and stirs at room temperature until the trimethylolethane is completely dissolved in the distilled water to obtain an aqueous solution of trimethylolethane;

[0013] S4. Trimethylolethane aqueous solution was added to graft-modified product I, and esterification and crosslinking reaction was carried out in a water bath to obtain crosslinked modified product II.

[0014] S5 is added sequentially to the crosslinked modified product II as a wetting agent and a water-retaining agent and stirred at a constant speed to obtain a highly wettable, binding polysaccharide-grafted foam dust-suppressing material.

[0015] Specifically, the heating and stirring process in step S1 is carried out at a temperature of 70°C for 1-2 hours and at a stirring rate of 300-400 r / min.

[0016] Specifically, the esterification grafting reaction in step S2 is carried out at a temperature of 70-90℃ for 3-4 hours and at a stirring rate of 300-400 r / min.

[0017] Specifically, the temperature of the esterification crosslinking reaction in step S4 is 70-90℃, the time is 3-4h, and the stirring rate is 300-400r / min.

[0018] Specifically, the reaction equation for the esterification grafting reaction in step S3 is as follows:

[0019]

[0020] Specifically, the reaction equation for the esterification crosslinking reaction in step S4 is as follows:

[0021]

[0022] The third objective of this invention is to provide an application of the aforementioned highly wettable, binding polysaccharide-grafted foam dust-suppressing material in dust suppression during coal mining.

[0023] The reaction mechanisms involved in this invention include:

[0024] (1) Esterification grafting reaction: The carboxyl group in the itaconic acid molecule undergoes an esterification condensation reaction with the active hydroxyl group on the Bletilla striata polysaccharide molecular chain, and water molecules are removed to form ester bonds (-COO-). This reaction introduces itaconic acid side chains containing double bonds into the Bletilla striata polysaccharide backbone to generate grafted modified product I. The structure retains unreacted free carboxyl groups (-COOH) to prepare for the cross-linking reaction of trimethylolethane introduced in the next step.

[0025] (2) Esterification and cross-linking reaction: The free carboxyl group (-COOH) in the grafted modified product I molecule and the hydroxyl group (-OH) in the trimethylolethane molecule undergo further esterification and cross-linking reaction. The grafted modified product I is bridged with the trimethylolethane chain through the newly formed ester bond (-COO-), which increases the hydroxyl content of the final product, improves hydrophilicity, and forms a three-dimensional network structure, further enhancing the stability of the foam dust suppression material.

[0026] Compared with the prior art, the present invention has the following beneficial technical effects:

[0027] (1) The Bletilla striata polysaccharide in this invention is a glucomannan with a unique structure. It contains a large amount of mucilage, has strong adhesion, and is rich in a large number of hydrophilic groups such as hydroxyl groups, which can significantly improve the wetting and penetration efficiency of dust-suppressing materials on dust particles. It is biodegradable, non-irritating, and non-toxic, and is an environmentally friendly material. Itaconic acid is a bio-based active monomer. The dicarboxyl group gives it excellent free radical polymerization activity, which can be grafted efficiently. After being discarded, it can be naturally decomposed and returned to the ecological cycle, which is highly consistent with the concept of green and sustainable development. This invention uses the esterification reaction of the carboxyl group (-COOH) of itaconic acid and its hydroxyl group (-OH) to successfully introduce the itaconic acid side chain containing double bonds into the molecular structure while retaining the biodegradability. The grafted modified product I generated by this reaction has an incompletely reacted carboxyl group (-COOH), which lays the foundation for the subsequent construction of a three-dimensional network. Moreover, the reaction process only uses water molecules as a byproduct, achieving zero-toxicity modification.

[0028] (2) Trimethylolethane in this invention is a tasteless white crystalline solid of a polyol with three primary hydroxyl groups. It has the characteristics of good fluidity and excellent chemical stability. Under natural conditions, it gradually hydrolyzes into water-soluble small molecules and participates in the natural carbon cycle. This invention uses the unreacted carboxyl groups (-COOH) in itaconic acid as crosslinking hubs. Through the abundant hydroxyl groups (-OH) in trimethylolethane, it undergoes a deep esterification reaction with it to form a high-density covalent crosslinking network structure, which fundamentally reconstructs the material properties, greatly improves the mechanical strength, and enables the foam solidification layer to resist various mechanical impacts. In addition, the newly added hydroxyl groups greatly increase the density of hydrophilic groups in the network, and work with the wetting agent to give the foam dust-reducing material high wettability. At the same time, it forms a hydrogen bond water-locking layer with the water-retaining agent to achieve efficient protection of the solidification layer.

[0029] (3) The foam dust-suppressing material prepared by this invention uses Bletilla striata polysaccharide, itaconic acid, trimethylolethane, dilute hydrochloric acid, wetting agent, water-retaining agent and distilled water as raw materials; the raw materials are readily available, environmentally friendly and highly biodegradable; the dust-suppressing material also has excellent wettability, adhesion and foaming properties, and can quickly encapsulate dust particles to achieve effective dust suppression. The grafting agent (itaconic acid) and crosslinking agent (trimethylolethane) used not only have biodegradable properties, but also have excellent free radical polymerization activity, and can efficiently carry out grafting and crosslinking reactions; forming a three-dimensional network with a high-strength skeleton, which not only retains the biodegradable properties, but also significantly improves the mechanical toughness and structural stability of the foam, can well wet the coal seam surface and form a hard and dense solidified layer, effectively resisting erosion and avoiding secondary dust re-entrainment caused by coal seam rupture. Attached Figure Description

[0030] Figure 1 This is a process flow diagram of the highly wettable, binding polysaccharide-grafted foam dust-suppressing material prepared in Example 1 of the present invention;

[0031] Figure 2 The diagram shows a comparison of the wetting properties of the dust-suppressing materials prepared in Examples 1-9 and Comparative Examples 1-2 of this invention. Detailed Implementation Plan

[0032] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. Unless otherwise defined, all technical and scientific terms used in this specification have the same meaning as commonly understood by those skilled in the art to which this invention pertains. The terminology used in this specification is for the purpose of describing specific embodiments only and is not intended to limit the present invention.

[0033] Example 1

[0034] Please see Figure 1 , Figure 1 This is a process flow diagram for preparing highly wettable, binding polysaccharide-grafted foam dust-suppressing material in Example 1 of the present invention. The specific steps include:

[0035] S1. Add 50 mL of distilled water and 13 g of Bletilla striata polysaccharide to a beaker in sequence. Place the beaker in a water bath at 70 °C and 300 r / min and heat it with magnetic stirring for 1.5 h to completely dissolve the Bletilla striata polysaccharide in the distilled water to obtain Bletilla striata polysaccharide aqueous solution a.

[0036] S2 added 8.5g itaconic acid to the aqueous solution of Bletilla striata polysaccharide a to obtain mixed solution a; after adjusting the pH of mixed solution a to 4 with dilute hydrochloric acid (concentration of 3%), it was placed in a water bath at 75℃ and 300r / min for esterification grafting reaction for 3h to obtain grafted modified product Ia;

[0037] S3 adds 50 mL of distilled water and 4.5 g of trimethylolethane to another beaker in sequence, and stirs evenly at room temperature for 1 h to completely dissolve the trimethylolethane in the distilled water, thus obtaining trimethylolethane aqueous solution a;

[0038] S4. Trimethylolethane aqueous solution a was added to the grafted modified product Ia and placed in a water bath at 75°C and 300 r / min for esterification and crosslinking reaction for 3 h to obtain crosslinked modified product IIa.

[0039] S5 added 0.4g Triton X-100 and 1g glycerol to the crosslinked modified product IIa in sequence, and stirred at a constant speed at room temperature to obtain a highly wettable, binding polysaccharide-grafted foam dust-suppressing material a.

[0040] Example 2

[0041] S1. Add 50 mL of distilled water and 13 g of Bletilla striata polysaccharide to a beaker in sequence. Place the beaker in a water bath at 70 °C and 300 r / min and heat and stir magnetically for 1.5 h to completely dissolve the Bletilla striata polysaccharide in the distilled water to obtain Bletilla striata polysaccharide aqueous solution b.

[0042] S2 added 10.5g itaconic acid to the aqueous solution b of Bletilla striata polysaccharide to obtain mixed solution b; after adjusting the pH of mixed solution b to 4 with dilute hydrochloric acid (concentration of 3%), it was placed in a water bath at 80℃ and 300r / min for 3h for esterification grafting reaction to obtain grafted modified product Ib.

[0043] S3 adds 50 mL of distilled water and 6.5 g of trimethylolethane to another beaker in sequence, and stirs evenly at room temperature for 1 h to completely dissolve the trimethylolethane in the distilled water, thus obtaining trimethylolethane aqueous solution b;

[0044] S4. Trimethylolethane aqueous solution b was added to the grafted modified product Ib, and the mixture was placed in a water bath at 80°C and 300 r / min for 3 h to carry out the esterification and crosslinking reaction to obtain the crosslinked modified product IIb.

[0045] S5 added 0.4g Triton X-100 and 1g glycerol to the crosslinked modified product IIb in sequence, and stirred at a constant speed at room temperature to obtain highly wettable, binding polysaccharide-grafted foam dust-suppressing material b.

[0046] Example 3

[0047] S1. Add 50 mL of distilled water and 13 g of Bletilla striata polysaccharide to a beaker in sequence. Place the beaker in a water bath at 70 °C and 300 r / min and heat it with magnetic stirring for 1.5 h to completely dissolve the Bletilla striata polysaccharide in the distilled water, and obtain Bletilla striata polysaccharide aqueous solution c.

[0048] S2 added 12.5g itaconic acid to the aqueous solution c of Bletilla striata polysaccharide to obtain mixed solution c; after adjusting the pH of mixed solution c to 4 with dilute hydrochloric acid (concentration of 3%), it was placed in a water bath at 85℃ and 300r / min for 3h for esterification grafting reaction to obtain grafted modified product Ic;

[0049] S3. Add 50 mL of distilled water and 8.5 g of trimethylolethane to another beaker in sequence, and stir evenly at room temperature for 1 h to completely dissolve the trimethylolethane in the distilled water to obtain trimethylolethane aqueous solution c.

[0050] S4. Trimethylolethane aqueous solution c was added to the grafted modified product Ic, and the mixture was placed in a water bath at 85°C and 300 r / min for 3 h to carry out the esterification and crosslinking reaction to obtain the crosslinked modified product IIc.

[0051] S5 added 0.4g Triton X-100 and 1g glycerol to the crosslinked modified product IIc in sequence, and stirred at a constant speed at room temperature to obtain highly wettable, binding polysaccharide-grafted foam dust-suppressing material c.

[0052] Example 4

[0053] S1. Add 50 mL of distilled water and 15 g of Bletilla striata polysaccharide to a beaker in sequence. Place the beaker in a water bath at 70 °C and 300 r / min and heat and stir magnetically for 1.5 h to completely dissolve the Bletilla striata polysaccharide in the distilled water to obtain a Bletilla striata polysaccharide aqueous solution d.

[0054] S2 added 10.5g itaconic acid to the aqueous solution d of Bletilla striata polysaccharide to obtain mixed solution d; after adjusting the pH of mixed solution d to 4 with dilute hydrochloric acid (concentration of 3%), it was placed in a water bath at 80℃ and 300r / min for 3h for esterification grafting reaction to obtain grafted modified product Id;

[0055] S3. Add 50 mL of distilled water and 6.5 g of trimethylolethane to another beaker in sequence, and stir evenly at room temperature for 1 h to completely dissolve the trimethylolethane in the distilled water to obtain a trimethylolethane aqueous solution d.

[0056] S4. Trimethylolethane aqueous solution d was added to the grafted modified product Id, and the mixture was placed in a water bath at 80℃ and 300r / min for 3h for esterification and crosslinking reaction to obtain crosslinked modified product IId.

[0057] S5 added 0.4g Triton X-100 and 1g glycerol to the crosslinked modified product IId in sequence, and stirred at a constant speed at room temperature to obtain a highly wettable, binding polysaccharide-grafted foam dust-suppressing material d.

[0058] Example 5

[0059] S1. Add 50 mL of distilled water and 15 g of Bletilla striata polysaccharide to a beaker in sequence. Place the beaker in a water bath at 70 °C and 300 r / min and heat it with magnetic stirring for 1.5 h to completely dissolve the Bletilla striata polysaccharide in the distilled water, and obtain Bletilla striata polysaccharide aqueous solution e.

[0060] S2 added 10.5g itaconic acid to the aqueous solution e of Bletilla striata polysaccharide to obtain mixed solution e; after adjusting the pH of mixed solution e to 4 with dilute hydrochloric acid (concentration of 3%), it was placed in a water bath at 75℃ and 300r / min for 3h for esterification grafting reaction to obtain grafted modified product Ie.

[0061] S3. Add 50 mL of distilled water and 8.5 g of trimethylolethane to another beaker in sequence, and stir evenly at room temperature for 1 h to completely dissolve the trimethylolethane in the distilled water to obtain an aqueous solution of trimethylolethane e.

[0062] S4. Trimethylolethane aqueous solution e was added to the grafted modified product Ie, and the mixture was placed in a water bath at 75°C and 300 r / min for 3 h to carry out the esterification and crosslinking reaction to obtain the crosslinked modified product IIe.

[0063] S5 added 0.4g Triton X-100 and 1g glycerol to the crosslinked modified product IIe in sequence, and stirred at a constant speed at room temperature to obtain a highly wettable, binding polysaccharide-grafted foam dust-suppressing material e.

[0064] Example 6

[0065] S1. Add 50 mL of distilled water and 15 g of Bletilla striata polysaccharide to a beaker in sequence. Place the beaker in a water bath at 70 °C and 400 r / min and heat and stir magnetically for 2 h to completely dissolve the Bletilla striata polysaccharide in the distilled water to obtain a Bletilla striata polysaccharide aqueous solution f.

[0066] S2 added 12.5g itaconic acid to the aqueous solution f of Bletilla striata polysaccharide to obtain mixed solution f; after adjusting the pH of mixed solution f to 4 with dilute hydrochloric acid (concentration of 3%), it was placed in a water bath at 90℃ and 400r / min for 4h for esterification grafting reaction to obtain grafted modified product If;

[0067] S3. Add 50 mL of distilled water and 4.5 g of trimethylolethane to another beaker in sequence, and stir evenly at room temperature for 1 h to completely dissolve the trimethylolethane in the distilled water to obtain a trimethylolethane aqueous solution f.

[0068] S4. Trimethylolethane aqueous solution f was added to the grafted modified product If, and the mixture was placed in a water bath at 90℃ and 400r / min for 4h for esterification and crosslinking reaction to obtain the crosslinked modified product IIf.

[0069] S5 added 0.4g Triton X-100 and 1g glycerol to the crosslinked modified product IIf, and stirred at a constant speed at room temperature to obtain a highly wettable, binding polysaccharide-grafted foam dust-suppressing material f.

[0070] Example 7

[0071] S1. Add 50 mL of distilled water and 17 g of Bletilla striata polysaccharide to a beaker in sequence. Place the beaker in a water bath at 70 °C and 350 r / min and heat and stir magnetically for 1 h to completely dissolve the Bletilla striata polysaccharide in the distilled water to obtain a Bletilla striata polysaccharide aqueous solution j.

[0072] S2 added 8.5 g of itaconic acid to the aqueous solution j of Bletilla striata polysaccharide to obtain mixed solution j; after adjusting the pH of mixed solution j to 4 with dilute hydrochloric acid (concentration of 3%), it was placed in a water bath at 80℃ and 350 r / min for 3.5 h for esterification grafting reaction to obtain grafted modified product Ij;

[0073] S3. Add 50 mL of distilled water and 8.5 g of trimethylolethane to another beaker in sequence, and stir evenly at room temperature for 1 h to completely dissolve the trimethylolethane in the distilled water to obtain a trimethylolethane aqueous solution j.

[0074] S4. Trimethylolethane aqueous solution j was added to the grafted modified product Ij, and the mixture was placed in a water bath at 80℃ and 350r / min for 3.5h for esterification and crosslinking reaction to obtain crosslinked modified product IIj.

[0075] S5 added 0.4g Triton X-100 and 1g glycerol to the crosslinked modified product IIj in sequence, and stirred at a constant speed at room temperature to obtain a polysaccharide-grafted foam dust-suppressing material j with high wettability and binding properties.

[0076] Example 8

[0077] S1. Add 50 mL of distilled water and 17 g of Bletilla striata polysaccharide to a beaker in sequence. Place the beaker in a water bath at 70 °C and 300 r / min and heat it with magnetic stirring for 1.5 h to completely dissolve the Bletilla striata polysaccharide in the distilled water to obtain Bletilla striata polysaccharide aqueous solution k.

[0078] S2 added 10.5g itaconic acid to the aqueous solution k of Bletilla striata polysaccharide to obtain mixed solution k; after adjusting the pH of mixed solution k to 4 with dilute hydrochloric acid (concentration of 3%), it was placed in a water bath at 85℃ and 300r / min for 3h for esterification grafting reaction to obtain grafted modified product Ik;

[0079] S3 adds 50 mL of distilled water and 4.5 g of trimethylolethane to another beaker, and stirs evenly at room temperature for 1 h to completely dissolve the trimethylolethane in the distilled water, thus obtaining a trimethylolethane aqueous solution k.

[0080] S4. Trimethylolethane aqueous solution k was added to the grafted modified product Ik, and the mixture was placed in a water bath at 85°C and 300 r / min for 3 h to carry out the esterification and crosslinking reaction to obtain the crosslinked modified product IIk.

[0081] S5 added 0.4g Triton X-100 and 1g glycerol to the crosslinked modified product IIk in sequence, and stirred at a constant speed at room temperature to obtain highly wettable, binding polysaccharide-grafted foam dust-suppressing material k.

[0082] Example 9

[0083] S1. Add 50 mL of distilled water and 17 g of Bletilla striata polysaccharide to a beaker in sequence. Place the beaker in a water bath at 70 °C and 300 r / min and heat and stir magnetically for 1.5 h to completely dissolve the Bletilla striata polysaccharide in the distilled water to obtain a Bletilla striata polysaccharide aqueous solution m.

[0084] S2 added 12.5g itaconic acid to the aqueous solution m of Bletilla striata polysaccharide to obtain a mixed solution m; the pH of the mixed solution m was adjusted to 4 with dilute hydrochloric acid (concentration of 3%), and then placed in a water bath at 75℃ and 300r / min for 3h for esterification grafting reaction to obtain grafted modified product Im;

[0085] S3 adds 50 mL of distilled water and 6.5 g of trimethylolethane to another beaker in sequence, and stirs evenly at room temperature for 1 h to completely dissolve the trimethylolethane in the distilled water, thus obtaining a trimethylolethane aqueous solution m;

[0086] S4. Trimethylolethane aqueous solution m was added to the grafted modified product Im, and the mixture was placed in a water bath at 75°C and 300 r / min for 3 h for esterification and crosslinking reaction to obtain crosslinked modified product IIm.

[0087] S5 added 0.3g Triton X-100 and 0.8g glycerol to the crosslinked modified product IIm in sequence, and stirred at a constant speed at room temperature to obtain a highly wettable, binding polysaccharide-grafted foam dust-suppressing material m.

[0088] Comparative Example 1

[0089] Add 100 mL of distilled water and 13 g of Bletilla striata polysaccharide to a beaker, heat in a water bath at 70 °C, and stir magnetically at 300 r / min for 1.5 h until completely dissolved to obtain the dust-suppressing material A prepared in Comparative Example 1.

[0090] Comparative Example 2

[0091] Add 13g of Bletilla striata polysaccharide and 4.5g of trimethylolethane to a beaker containing 100mL of distilled water, heat in a water bath at 70℃, and stir magnetically at 300r / min for 1.5h until completely dissolved to obtain the dust-suppressing material B prepared in Comparative Example 2.

[0092] Performance testing

[0093] The wettability, adhesion and foaming properties of the dust-suppressing materials prepared in Examples 1-9 and Comparative Examples 1-2 were tested.

[0094] The wettability test method is as follows: The foam dust-suppressing material solutions prepared in Examples 1-9 and Comparative Examples 1 and 2 were prepared. The experimental coal powder was compacted under a pressure of 20 MPa using a powder compactor to form cylindrical test pieces with a smoothed surface. The contact angle of the foam dust-suppressing material solutions prepared in Examples 1-9 and Comparative Examples 1-2 on the coal surface was measured using a JC2000D2 contact angle meter. Each group was measured three times, and the average value was taken as the final contact angle. The contact angle (θ) refers to the angle between the gas-liquid interface and the solid-liquid interface at the gas-liquid-solid three-phase interface when a droplet contacts a solid surface. When θ < 90°, it is wettable; when θ > 90°, it is non-wettable. The smaller the θ, the better the wettability.

[0095] Wettability test results: Please refer to Table 1, which shows the contact angle test results of the dust-suppressing materials prepared in Example-9 and Comparative Examples 1-2 of this invention.

[0096] Table 1

[0097]

[0098]

[0099] As shown in Table 1, the contact angles of the foam dust-suppressing material solutions prepared in Examples 1-9 are significantly lower than those in Comparative Examples 1 and 2, with Example 4 having the smallest contact angle at 35.31°. This indicates that after the modified dust-suppressing material solution has more hydroxyl groups, these hydrophilic groups can enhance the interaction between the solution molecules and the solid surface, thereby reducing the contact angle and achieving a good wetting effect.

[0100] The adhesion test method is as follows: Prepare the foam dust-suppressing material solutions obtained in Examples 1-9 and Comparative Examples 1 and 2, foam them, and spray them onto coal piles of the same mass. Place the coal piles that have formed a solidified layer after 60 hours at 10 cm from the air outlet of the experimental device, blow them continuously at a constant wind speed of 15 m / s for 1 hour, weigh them and record the data. Record the weight of the coal piles before and after the test and calculate the mass loss rate to explore and study their adhesion performance.

[0101] Adhesion test results: Please refer to Table 2, which shows the adhesion test results of the dust-suppressing materials prepared in Example-9 and Comparative Examples 1-2 of this invention.

[0102] Table 2

[0103]

[0104] As shown in Table 2, after spraying with the materials prepared in Comparative Examples 1 and 2, the coal pile's consolidation layer was destroyed by strong winds, and the coal dust on the coal seam surface was quickly blown away, resulting in mass loss rates as high as 65.2% and 54.8%, respectively. The coal piles sprayed with the foam dust-suppressing material solutions prepared in Examples 1-9 suffered almost no loss, with a maximum loss rate of only 4.8%. Example 4 showed the lowest mass loss rate, as low as 2.7%. The experiment demonstrates that after spraying with the foam dust-suppressing material solutions prepared in Examples 1-9, a hard and dense consolidation layer was formed on the surface of the coal pile, creating a protective layer to protect the internal coal dust from wind erosion and prevent secondary dust re-entrainment caused by coal seam cracking. This layer exhibits good adhesion.

[0105] The foaming test method is as follows: Prepare 200 ml of the foam dust-suppressing material solution obtained in Examples 1-9 and Comparative Examples 1 and 2 in a beaker. Measure 40 ml of the solution using a graduated cylinder and stir it under a stirrer. After foaming for 30 seconds, immediately pour it into the graduated cylinder and record the foam volume. To reduce error, all data are measured three times and the average value is taken. The foaming rate can be represented by α.

[0106]

[0107] In the formula, α is the foaming rate; w1 is the volume of foam after foaming; and w0 is the volume of solution before foaming.

[0108] Foaming test results: Please refer to Table 3, which shows the foaming test results of the dust-suppressing materials prepared in Example-9 and Comparative Examples 1-2 of this invention.

[0109] Table 3

[0110]

[0111] As shown in Table 3, the foam dust suppression materials prepared in Examples 1-9 are all higher than those in Comparative Examples 1-2. The foaming rate in Example 4 is as high as 475%. This is because the surfactant Triton X-100 was added in the example, which can effectively reduce the surface tension of the solution, promote foam formation, and the liquid film structure is compact, which can prolong the foam half-life and is suitable for the dynamic dust environment of coal mines.

[0112] This invention tests the wettability, foaming properties, and adhesiveness of dust-suppressing materials prepared in Examples 1-9 by designing different formulations. Notably, the dust-suppressing material prepared in Example 4 exhibits the lowest mass loss rate, highest foaming rate, and smallest contact angle, and demonstrates excellent wetting effect on the experimental coal sample. Therefore, under the condition of 100 mL distilled water, the preferred addition amounts of other raw materials are: 15 g of Bletilla striata polysaccharide, 10.5 g of itaconic acid, 6.5 g of trimethylolethane, 4.2 g of dilute hydrochloric acid, 0.4 g of wetting agent, and 1 g of water-retaining agent. The dust-suppressing material prepared under this preferred formulation exhibits superior wettability, adhesiveness, and foaming properties, which is more conducive to forming a hard and dense consolidation layer to protect the internal coal dust from wind erosion and prevent secondary dust re-entrainment caused by coal seam rupture.

[0113] In summary, the highly wettable and binding polysaccharide-grafted foam dust-suppressing material prepared by this invention can effectively wet the coal seam surface and form a hard and dense consolidation layer. It also has good foaming properties and can quickly encapsulate dust particles to achieve effective dust suppression.

[0114] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A highly wettable, binding polysaccharide-grafted foam dust-suppressing material, characterized in that, The foam dust-suppressing material comprises the following raw materials in parts by weight: 10-16 parts of Bletilla striata polysaccharide, 8-12 parts of itaconic acid, 5-8 parts of trimethylolpropane, 3-5 parts of dilute hydrochloric acid, 0.3-0.8 parts of wetting agent, 2-4 parts of water-retaining agent, and 100-300 parts of distilled water.

2. The foam dust-suppressing material according to claim 1, characterized in that, The wetting agent is Triton X-100; the water-retaining agent is glycerin; and the concentration of the dilute hydrochloric acid is 3%.

3. The foam dust-suppressing material according to claim 1, characterized in that, When the amount of distilled water is 100 mL, the preferred weights of the other raw materials are: 15 g of Bletilla striata polysaccharide, 10.5 g of itaconic acid, 6.5 g of trimethylol ethane, 0.4 g of wetting agent and 1 g of water-retaining agent.

4. A method for preparing a highly wettable, binding polysaccharide-grafted foam dust-suppressing material as described in any one of claims 1-3, characterized in that, The preparation method includes the following steps: S1. Add distilled water and Bletilla striata polysaccharide to a beaker in sequence. Place the beaker in a water bath and heat and stir to completely dissolve the Bletilla striata polysaccharide in the distilled water to obtain a Bletilla striata polysaccharide aqueous solution. S2 added itaconic acid to the aqueous solution of Bletilla striata polysaccharide to obtain a mixed solution; the pH of the mixed solution was adjusted to 4 with dilute hydrochloric acid and then an esterification grafting reaction was carried out to obtain grafted modified product I; S3 adds distilled water and trimethylolethane to another beaker in sequence, and stirs at room temperature until the trimethylolethane is completely dissolved in the distilled water to obtain an aqueous solution of trimethylolethane; S4. Trimethylolethane aqueous solution was added to graft-modified product I, and esterification and crosslinking reaction was carried out in a water bath to obtain crosslinked modified product II. S5 is added sequentially to the crosslinked modified product II as a wetting agent and a water-retaining agent and stirred at a constant speed to obtain a highly wettable, binding polysaccharide-grafted foam dust-suppressing material.

5. The preparation method according to claim 4, characterized in that, The heating and stirring process in step S1 is carried out at a temperature of 70°C for 1-2 hours and at a stirring rate of 300-400 r / min.

6. The preparation method according to claim 4, characterized in that, The esterification grafting reaction in step S2 is carried out at a temperature of 70-90℃ for 3-4 hours and at a stirring rate of 300-400 r / min.

7. The preparation method according to claim 4, characterized in that, The temperature of the esterification crosslinking reaction in step S4 is 70-90℃, the time is 3-4h, and the stirring rate is 300-400r / min.

8. The preparation method according to claim 4, characterized in that, The reaction equation for the esterification grafting reaction in step S3 is:

9. The preparation method according to claim 4, characterized in that, The reaction equation for the esterification crosslinking reaction in step S4 is:

10. The application of a highly wettable, binding polysaccharide-grafted foam dust suppressant material as described in any one of claims 1-3 in dust suppression during coal mining.

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