Efficient wetting and agglomeration composite dust suppression material as well as preparation method and application thereof

Abstract

The invention discloses an efficient wetting and agglomeration composite dust suppression material and a preparation method and application thereof.The preparation method includes the following steps that 1, water, artemisia seed gum and ethyl alcohol are added into a container and stirred to be uniform, then a NaOH solution is dropwise added, alkalization is conducted for 30 min to 1 h, and a mixed solution I is obtained; (2) adding sodium chloroacetate and epoxypropane into the mixed solution I, heating to react until the reaction is complete, cooling the mixed solution to room temperature, and dropwise adding hydrochloric acid while stirring to neutralize until the pH is neutral, so as to obtain a mixed solution II; and (3) adding polyacrylamide into the mixed solution II, heating to react until the reaction is complete, and adding a surfactant to obtain a dust suppressant solution. The dust suppressant has efficient wetting and coagulation effects, the anti-interference capability of a consolidation layer is improved, water evaporation is effectively slowed down, and the action time of the dust suppressant is prolonged.

Description

Technical Field

[0001] The invention relates to the technical field of dust suppressants, and in particular to a high-efficiency wetting and condensing composite dust suppressant material and a preparation method and application thereof. Background Art

[0002] In recent years, with the continuous improvement of the mechanization level of coal mining, the widespread use of highly mechanized equipment such as comprehensive excavation and comprehensive mining has significantly increased coal production, but this has been accompanied by a substantial increase in the amount of coal mine dust, which has had a serious impact on the working environment of the mine and the health of the workers. Therefore, the control of mine dust has become an issue that needs to be urgently addressed.

[0003] Among the many dust prevention measures, chemical dust suppressants have shown more significant application potential compared to traditional physical dust suppression methods due to their high dust suppression efficiency, long-lasting action time and relatively simple operation process. In the complex process of dust control, wetting is a key step in suppressing dust flying. However, although the existing wetting dust suppressants have played a role to a certain extent, they still face many challenges in practical applications. For example, the scope of application of most dust suppressants is relatively narrow, and frequent spraying is required to maintain the effect, which not only increases the economic cost, but also may cause secondary pollution problems due to excessive use. More importantly, this type of dust suppressant often lacks sufficient coagulation ability after wetting the dust, resulting in secondary dust after drying, and the dust suppression effect is difficult to achieve the expected effect. Therefore, there is an urgent need to develop a new type of dust suppressant that can effectively suppress dust and has efficient wetting and coagulation capabilities. Summary of the invention

[0004] In view of the deficiencies in the prior art, the first purpose of the present invention is to provide a method for preparing a highly efficient wetting and condensing composite dust suppression material, the second purpose is to provide a highly efficient wetting and condensing composite dust suppression material prepared thereby, and the third purpose is to provide its application. The composite dust suppression material has highly efficient wetting and condensing effects, improves the anti-interference ability of the consolidation layer, effectively slows down the evaporation of water, and prolongs the action time of the dust suppressant.

[0005] In order to achieve the above first purpose, the present invention adopts the following technical solution: a method for preparing a highly efficient wetting and condensing composite dust suppression material, characterized in that the preparation is carried out according to the following steps:

[0006] (1) Add water, Artemisia ordosica seed gum and ethanol into a container, stir evenly, then add NaOH solution dropwise, alkalize for 30 min-1 h, and obtain mixed solution I;

[0007] (2) adding sodium chloroacetate and propylene oxide to the mixed solution I, heating the mixture to react until the reaction is complete, cooling the mixed solution to room temperature, and then adding hydrochloric acid dropwise while stirring to neutralize the mixture until the pH is neutral, thereby obtaining a mixed solution II;

[0008] (3) Add polyacrylamide to the mixed solution II, raise the temperature to react until the reaction is complete, and add a surfactant to obtain a dust suppressant solution.

[0009] In the above scheme: according to the mass parts, the added amount of each substance in every 1000 parts of water is: 2-10 parts of artemisia seed gum, 15-95 parts of anhydrous ethanol, 0.5-1 part of sodium chloroacetate, 0.3-0.4 parts of propylene oxide, 1.5-5.5 parts of polyacrylamide, 0.4-1.2 parts of sodium hydroxide, and 8-12 parts of wetting agent.

[0010] In the above scheme: the reaction temperature of step (2) is 55-65°C, and the reaction time is 2.5-3.5h.

[0011] In the above scheme: in step (3), the reaction temperature is 70-80°C and the reaction time is 45min-1h.

[0012] In the above scheme: the water is distilled water.

[0013] In the above scheme: the wetting agent is sodium lauryl sulfate.

[0014] The second object of the present invention is achieved in this way: a highly permeable polymer dust suppressant prepared by the preparation method of the efficient wetting and condensation composite dust suppressant material.

[0015] The third object of the present invention is achieved by: applying the highly efficient wetting and condensing composite dust suppression material to dust suppression in coal mines.

[0016] In the present invention, the artemisia seed gum is a hydrophilic colloid extracted from the epidermis of artemisia seeds, has stable chemical properties, does not cause pollution, is an environmentally friendly material, and has strong bonding ability. The artemisia seed gum contains cross-linked polysaccharides, and the formed consolidation layer has good permeability and compression resistance.

[0017] Polyacrylamide has high permeability, is easy to degrade, is harmless to the environment, produces almost no secondary pollution during use, and has low cost and good economic benefits. Therefore, using it to prepare dust suppressants not only has the advantages of high efficiency, economy and environmental protection, but also provides good consolidation layer strength and permeability. It is an ideal dust suppression material.

[0018] As an etherifying agent, sodium chloroacetate can undergo efficient etherification reaction with substrates under appropriate conditions. When used in carboxymethylation reaction, its product has excellent physical and chemical properties, such as high salt and temperature resistance and low viscosity.

[0019] Propylene oxide has high reactivity and contains epoxy groups in its molecules. It can react with a variety of organic substances such as alcohols, phenols, amines, etc. to undergo epoxy ring-opening reactions to form new compounds, making it an important reaction intermediate.

[0020] Sodium dodecyl sulfate is an anionic surfactant with good emulsification, foaming and water solubility. Sodium dodecyl sulfate has good biodegradability and is environmentally friendly. Sodium dodecyl sulfate is stable in aqueous solutions with a wide pH value and is resistant to alkali and hard water.

[0021] Reaction formula of the present invention is as follows:

[0022] (1) Etherification reaction-carboxymethylation

[0023]

[0024] (2) Etherification reaction-hydroxypropylation

[0025]

[0026] (3) Polymer chain structure

[0027]

[0028] AG-OH represents Artemisia seed gum. In (3), in addition to the amide bonds formed, hydrogen bonds also exist among the hydroxyl, amino, and carboxyl groups in the product, thus forming a stable polymer chain structure.

[0029] Under alkaline conditions, the hydroxyl groups (-OH) on the macromolecular chain of Artemisia sphaerocephala seed gum are converted into alkoxy anions (-O-), and the chloromethyl groups (-CH2Cl) of sodium chloroacetate react with the alkoxy anions on the Artemisia sphaerocephala seed gum to undergo nucleophilic substitution reactions, introducing carboxymethyl groups (-CH2COOH) to obtain modified carboxymethyl Artemisia sphaerocephala seed gum. While the main reaction is taking place, propylene oxide is used as a secondary etherifying agent to perform hydroxypropyl modification on the Artemisia sphaerocephala seed gum, introducing hydroxypropyl groups. The carboxyl (-CH2COOH) groups contained in the modified Artemisia sphaerocephala seed gum and the amino (-NH2) groups on the polyacrylamide molecular chain can undergo copolymerization to form amide bonds, thereby forming a copolymer. The carboxyl groups and hydroxyl groups in the modified Artemisia sphaerocephala seed gum and the amino groups in the polyacrylamide form hydrogen bonds, and a stable structure is formed through hydrogen bond interactions.

[0030] Compared with the prior art, the present invention has the following beneficial effects:

[0031] (1) The present invention uses an etherification modification method to modify the Artemisia seed gum, reduce water insoluble matter, and improve fluidity. The introduction of carboxyl groups into the Artemisia seed gum molecules significantly improves its water solubility and wettability. At the same time, the steric hindrance generated by the introduced hydroxypropyl groups improves the thermal stability of the Artemisia seed gum. The modified Artemisia seed gum is copolymerized with polyacrylamide and then compounded with sodium dodecyl sulfate. Under the action of covalent bonds and non-covalent bonds, a polymer chain structure is formed, and finally a dust suppression material with efficient wetting and coagulation effects is obtained.

[0032] (2) When the dust suppressant developed by the present invention is applied to coal dust, the repulsive force between the lipophilic group of the surfactant sodium dodecyl sulfate and water molecules can be used to effectively reduce the surface tension, promote the dust suppressant to penetrate and fill the gaps between dust particles, and improve the hydrophilicity and wetting effect of the dust. The hydrophilic groups in the dust suppressant, hydroxyl and carboxyl, can generate electrostatic effects with nitrogen-containing functional groups in the dust and form hydrogen bonds with oxygen-containing functional groups, so that the dust suppressant is combined with dust particles, enhancing the agglomeration ability of the particles, and achieving a water retention effect through combination with water molecules.

[0033] (3) After being sprayed, the dust suppressant prepared by the present invention can aggregate dust particles, increase the dust particle size, and reduce dust caused by natural wind and induced wind flow. In the process of heat absorption and water evaporation in the external environment, a consolidation layer is formed on the surface of the coal dust. The addition of polyacrylamide enhances the structural rigidity of the consolidation layer, prevents cracking, improves the anti-interference ability of the consolidation layer, effectively slows down water evaporation, and prolongs the action time of the dust suppressant. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 is the contact angle of comparative example 1 and embodiment 7 at 2s.

[0035] Figure 2 The wind erosion resistance diagram of the embodiments and comparative examples.

[0036] Figure 3 It is a process flow chart of the present invention. DETAILED DESCRIPTION

[0037] The present invention is further described in detail below through specific embodiments:

[0038] Example 1

[0039] Add 100mL of distilled water, 0.2g of Artemisia seed gum and 7.5g of ethanol to a three-necked flask, stir evenly and then add NaOH solution dropwise, the amount of sodium hydroxide is 0.04g, alkalize at 20℃ for 30min, and obtain mixed solution I. Then slowly add 0.05g of sodium chloroacetate and 0.03g of propylene oxide to mixed solution I, heat to 55℃ in a water bath, and stop after 2.5h of reaction. After the mixed solution is cooled to room temperature, hydrochloric acid is added dropwise while stirring to neutralize to obtain mixed solution II. Continue to add 0.15g of polyacrylamide to mixed solution II, slowly heat to 70℃, react for 1h, and add 0.8g of sodium dodecyl sulfate to obtain a dust suppressant solution.

[0040] Example 2

[0041] Add 100mL of distilled water, 0.2g of Artemisia seed gum and 7.5g of ethanol to a three-necked flask, stir evenly and then add NaOH solution dropwise, the amount of sodium hydroxide is 0.04g, alkalize at 20℃ for 30min, and obtain mixed solution I. Then slowly add 0.07g of sodium chloroacetate and 0.05g of propylene oxide to mixed solution I, heat to 55℃ in a water bath, and stop after 2.5h of reaction. After the mixed solution is cooled to room temperature, hydrochloric acid is added dropwise while stirring to neutralize to obtain mixed solution II. Continue to add 0.25g of polyacrylamide to mixed solution II, slowly heat to 70℃, react for 1h, and add 0.8g of sodium dodecyl sulfate to obtain a dust suppressant solution.

[0042] Example 3

[0043] Add 100mL of distilled water, 0.2g of Artemisia seed gum and 1.5g of anhydrous ethanol to a three-necked flask, stir evenly and then add NaOH solution dropwise, the amount of sodium hydroxide is 0.04g, alkalize at 20℃ for 30min, and obtain mixed solution I. Then slowly add 0.07g of sodium chloroacetate and 0.04g of propylene oxide to mixed solution I, heat to 55℃ in a water bath, and stop after 3.5h of reaction. After the mixed solution is cooled to room temperature, hydrochloric acid is added dropwise while stirring to neutralize to obtain mixed solution II. Continue to add 0.35g of polyacrylamide to mixed solution II, slowly heat to 70℃, react for 1h, and add 0.8g of sodium dodecyl sulfate to obtain a dust suppressant solution.

[0044] Example 4

[0045] Add 100mL of distilled water, 0.2g of Artemisia seed gum and 7.5g of ethanol to a three-necked flask, stir evenly and then add NaOH solution dropwise, the amount of sodium hydroxide is 0.04g, alkalize at 20℃ for 30min, and obtain mixed solution I. Then slowly add 0.05g of sodium chloroacetate and 0.03g of propylene oxide to mixed solution I, heat to 60℃ in a water bath, stop after 3h of reaction, cool the mixed solution to room temperature, add hydrochloric acid dropwise while stirring to neutralize to obtain mixed solution II. Continue to add 0.15g of polyacrylamide to mixed solution II, slowly heat to 50℃, react for 45min, and add 0.8g of sodium dodecyl sulfate to obtain dust suppressant solution.

[0046] Example 5

[0047] Add 100mL of distilled water, 0.4g of Artemisia seed gum and 95g of ethanol to a three-necked flask, stir evenly and then add NaOH solution dropwise, the amount of sodium hydroxide is 0.04g, alkalize at 20℃ for 30min, and obtain mixed solution I. Then slowly add 0.06g of sodium chloroacetate and 0.04g of propylene oxide to mixed solution I, heat to 60℃ in a water bath, and stop after 2.5h of reaction. After the mixed solution is cooled to room temperature, hydrochloric acid is added dropwise while stirring to neutralize to obtain mixed solution II. Continue to add 0.15g of polyacrylamide to mixed solution II, slowly heat to 70℃, react for 1h, and add 1.0g of sodium dodecyl sulfate to obtain a dust suppressant solution.

[0048] Example 6

[0049] Add 100mL of distilled water, 0.4g of Artemisia seed gum and 1.5g of ethanol to a three-necked flask, stir evenly and then add NaOH solution dropwise, the amount of sodium hydroxide is 0.1g, alkalize at 20℃ for 1h, and obtain mixed solution I. Then slowly add 0.07g of sodium chloroacetate and 0.03g of propylene oxide to mixed solution I, heat to 60℃ in a water bath, and stop after 3h of reaction. After the mixed solution is cooled to room temperature, hydrochloric acid is added dropwise while stirring to neutralize to obtain mixed solution II. Continue to add 0.25g of polyacrylamide to mixed solution II, slowly heat to 70℃, react for 1h, and add 1.0g of sodium dodecyl sulfate to obtain a dust suppressant solution.

[0050] Example 7

[0051] Add 100mL of distilled water, 0.6g of Artemisia seed gum and 9.5g of ethanol to a three-necked flask, stir evenly and then add NaOH solution dropwise, the amount of sodium hydroxide is 0.12g, alkalize at 20℃ for 1h, and obtain mixed solution I. Then slowly add 0.05g of sodium chloroacetate and 0.04g of propylene oxide to mixed solution I, heat to 65℃ in a water bath, and stop after 2.5h of reaction. After the mixed solution is cooled to room temperature, hydrochloric acid is added dropwise while stirring to neutralize to obtain mixed solution II. Continue to add 0.25g of polyacrylamide to mixed solution II, slowly heat to 70℃, react for 1h, and add 1.2g of sodium dodecyl sulfate to obtain a dust suppressant solution.

[0052] Example 8

[0053] Add 100mL of distilled water, 0.6g of Artemisia seed gum and 9.5g of ethanol to a three-necked flask, stir evenly and then add NaOH solution dropwise, the amount of sodium hydroxide is 0.12g, alkalize at 20℃ for 1h, and obtain mixed solution I. Then slowly add 0.06g of sodium chloroacetate and 0.03g of propylene oxide to mixed solution I, heat to 65℃ in a water bath, and stop after 3.5h of reaction. After the mixed solution is cooled to room temperature, hydrochloric acid is added dropwise while stirring to neutralize to obtain mixed solution II. Continue to add 0.35g of polyacrylamide to mixed solution II, slowly heat to 70℃, react for 1h, and add 1.2g of sodium dodecyl sulfate to obtain a dust suppressant solution.

[0054] Example 9

[0055] Add 100mL of distilled water, 1g of Artemisia seed gum and 9.5g of ethanol to a three-necked flask, stir evenly and then add NaOH solution dropwise, the amount of sodium hydroxide is 0.12g, alkalize at 20℃ for 1h, and obtain mixed solution I. Then slowly add 0.1g of sodium chloroacetate and 0.04g of propylene oxide to mixed solution I, heat to 65℃ in a water bath, and stop after 2.5h of reaction. After the mixed solution is cooled to room temperature, hydrochloric acid is added dropwise while stirring to neutralize to obtain mixed solution II. Continue to add 0.55g of polyacrylamide to mixed solution II, slowly heat to 70℃, react for 1h, and add 1.2g of sodium dodecyl sulfate to obtain a dust suppressant solution.

[0056] Comparative Example 1

[0057] Add 0.4 g of Artemisia ordosica seed gum to a beaker and heat in 100 mL of distilled water bath until dissolved.

[0058] Comparative Example 2

[0059] Weigh 0.25 g of polyacrylamide into a beaker, add 100 mL of distilled water and heat until dissolved.

[0060] The effects of Examples 1-9 and Comparative Examples 1 and 2 are examined by experimental tests.

[0061] Test Example 1

[0062] The dust suppressants prepared in Examples 1-9 and Comparative Examples 1 and 2 were subjected to wettability tests.

[0063] The test method is as follows: take an equal amount of coal powder and put it into multiple tubes of the same size, shake the test tubes so that the coal samples are evenly distributed in them and the height is not less than 10 cm, then fix them on the test tube rack, take 10 mL of the solution of Examples 1-9 and Comparative Examples 1-2 and slowly drip them into each test tube, and use a stopwatch to record the penetration distance of each dust suppressant solution in the coal sample within 20 minutes, take the average value of multiple measurements, and calculate the corresponding penetration rate based on the penetration depth and time. The contact angle of the surface of the coal sample is measured with the help of an optical contact angle meter, the coal powder is pressed into a coal cake and placed on a glass slide on the sample table, and the contact angles of the embodiments and comparative examples dropped on the coal cake at 0s, 1s, and 2s are recorded respectively, and the test results are shown in Table 1 below.

[0064] Table 1 Wettability test

[0065]

[0066] Figure 1 The contact angles of Example 1 and Example 7 at 2s. The wettability experimental data in Table 1 show that under the same conditions, the penetration rates of Examples 1-9 are moderate and the penetration performance is ideal. Comparative Example 1 has a large viscosity and the worst penetration effect. The contact angles of Examples 1-9 and Comparative Example 1-2 dropped on the surface of the coal cake are decreasing with time. Among them, Example 7 has the largest change, and the contact angle decreases by 20.52° within 2s, while Comparative Example 1 only changes by 10.45°, and the contact angle remains at 53.78° after 2s, indicating that Examples 1-9 of the present invention can significantly improve the wettability of the coal dust surface, and can quickly penetrate the coal dust in a short time, thereby shortening the dust suppression time.

[0067] Test Example 2

[0068] The dust suppressants prepared in Examples 1-9 and Comparative Examples 1 and 2 were subjected to wind erosion resistance tests.

[0069] The test method is: 15g of the solution of Examples 1-9 and Comparative Examples 1-2 are sprayed on the surface of 5g of coal powder, and the dust is measured after drying for 48 hours under natural conditions, and the mass of the coal dust is recorded at this time. The wind speed of different samples is set to 1m / s, 3m / s, 5m / s, 7m / s and 9m / s respectively, and lasts for 10min. After each stage, the mass of the coal pile is measured and the wind erosion rate is calculated. The test results are as follows Figure 2 shown.

[0070] Figure 2The results show that under the condition of a wind speed of 1 m / s, there is almost no loss in the mass of the coal samples treated with Examples 1-9, and under the erosion condition of 9 m / s, the mass loss rate of the coal sample treated with Example 4 remains low, with a wind erosion rate of 12.77%, while the mass loss rate of the coal sample treated with Comparative Example 2 has reached 32.41%. This is because the molecules in the present invention form a network structure through hydrogen bonds, thereby effectively enhancing the strength of the dust solidification layer. It can be seen that the dust suppressant of the present invention has good wind erosion resistance.

[0071] In summary, the dust suppressant prepared by the present invention can suppress dust with high efficiency, effectively solve the technical problems of difficult wetting and poor condensation effect of traditional dust suppressants, and has good social benefits and considerable economic benefits.

[0072] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the purpose and scope of the technical solution of the present invention, which should be included in the scope of the claims of the present invention.

Claims

1. A method for preparing a highly efficient wetting and condensing composite dust suppression material, characterized in that: Prepare according to the following steps: (1) Add water, Artemisia ordosica seed gum and ethanol into a container, stir evenly, then add NaOH solution dropwise, alkalize for 30 min-1 h, and obtain mixed solution I; (2) adding sodium chloroacetate and propylene oxide to the mixed solution I, heating the mixture to react until the reaction is complete, cooling the mixed solution to room temperature, and then adding hydrochloric acid dropwise while stirring to neutralize the mixture until the pH is neutral, thereby obtaining a mixed solution II; (3) Add polyacrylamide to the mixed solution II, raise the temperature to react until the reaction is complete, and add a surfactant to obtain a dust suppressant solution.

2. The method for preparing the highly efficient wetting and condensing composite dust suppression material according to claim 1, characterized in that: According to the mass percentage, the added amount of each substance in every 1000 parts of water is: 2-10 parts of artemisia seed gum, 15-95 parts of anhydrous ethanol, 0.5-1 part of sodium chloroacetate, 0.3-0.4 parts of propylene oxide, 1.5-5.5 parts of polyacrylamide, 0.4-1.2 parts of sodium hydroxide, and 8-12 parts of wetting agent.

3. The method for preparing the highly efficient wetting and condensing composite dust suppression material according to claim 2 is characterized in that: The reaction temperature of step (2) is 55-65° C., and the reaction time is 2.5-3.5 h.

4. The method for preparing the highly efficient wetting and condensing composite dust suppression material according to claim 3 is characterized in that: In step (3), the reaction temperature is 70-80°C and the reaction time is 45min-1h.

5. The method for preparing the highly efficient wetting and condensing composite dust suppression material according to any one of claims 1 to 4, characterized in that: The water is distilled water, and the wetting agent is sodium lauryl sulfate.

6. A highly permeable polymer dust suppressant prepared by the method for preparing a highly efficient wetting and condensing composite dust suppressant material as described in any one of claims 1 to 5.

7. Use of the high-efficiency wetting and condensing composite dust suppression material according to claim 6 in dust suppression of coal mines.

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