Special dust suppressant under tunnel blasting condition and preparation method thereof

Abstract

The invention discloses a special dust suppressant under a tunnel blasting condition and a preparation method thereof. The invention relates to the technical field of dust suppressant preparation. The invention discloses a special dust suppressant under a tunnel blasting condition. The special dust suppressant comprises a component A and a component B, the component A comprises the following raw materials in parts by weight: 2-4 parts of sodium carboxymethyl starch; 3-15 parts of acrylic acid with a neutralization degree of 70%; 0.01 to 0.09 part of potassium persulfate; 0.01 to 0.06 part of sodium hydrogen sulfite; 0.01 to 0.15 part of N, N '-methylene bisacrylamide; and the component B is a surfactant which is one or a mixture of more of isodecyl alcohol polyoxyethylene ether and fatty alcohol polyoxyethylene ether. The preparation method is simple, the prepared special dust suppressant under the tunnel blasting condition can greatly reduce raised dust in the tunnel blasting period, dust falling in a short time is achieved, tunnel construction is facilitated, and the construction efficiency is improved.

Description

Technical Field

[0001] The invention relates to the technical field of dust suppressant preparation, in particular to a special dust suppressant for tunnel blasting conditions and a preparation method thereof. Background Art

[0002] The dust generated during tunnel construction blasting is an important source of dust generation during the construction process. During the tunnel construction process, due to the need for blasting, a large amount of dust will be generated in a short period of time, which will affect the construction efficiency. According to the occupational health regulations of the "Technical Specifications for Highway Tunnel Construction" (JTG / T 3660-2020), the dust concentration on the tunnel working face should not exceed 2 mg / m 3 Therefore, if dust cannot be effectively suppressed, the presence of large amounts of dust will be an important factor endangering the occupational health of construction workers. Therefore, it is of great significance to reduce dust efficiently and quickly. This can not only protect the health of workers, but also speed up the construction process and improve construction efficiency.

[0003] To address the problems of dust being difficult to settle in a short period of time, polluting the environment, and affecting construction operations, the traditional method is to spray large amounts of water and some chemical dust suppressants. These methods have solved the problem of flying dust to a certain extent, but there are still some shortcomings. For example, the use of water spraying is inconvenient to operate during tunnel construction, a large amount of water resources is wasted, and the effective dust suppression time is short. Some dust suppressants focus on forming a shell layer to prevent materials from piling up dust. The existing dust suppressants on the market include wetting type, condensing type, bonding type, composite type and other dust suppressants. For example, wetting type dust suppressants mainly suppress dust by increasing the humidity of the dust surface, but once the water evaporates, the dust will dissipate into the air again; the bonding type focuses on forming a shell to prevent the material from piling up dust; the ordinary dust suppressants on the market have relatively single dust suppression functions and are basically suitable for open-air occasions. They fail to take into account the characteristics of blasting and environmental closure in highway and railway tunnel construction, and must not be corrosive, eco-toxic, or have residues that are difficult to clean up. This limits the application scope of ordinary dust suppressants to occasions with low requirements, such as roads, material transport vehicles, material yards, etc., and cannot be widely used in tunnel construction scenarios of highway and railway construction.

[0004] Common dust suppressants typically contain polyacrylamide, sodium carboxymethyl cellulose, and sodium dodecylbenzene sulfonate. The chemical surfactant sodium dodecylbenzene sulfonate, currently used extensively in mines, is toxic and corrosive, potentially harmful to humans. Commercially available polymers, such as sodium polyacrylate, retain water but are expensive. Inorganic salts, such as calcium chloride, can easily seep into water bodies with rainwater, increasing groundwater chloride concentrations and threatening agricultural irrigation.

[0005] Dust suppressants used during tunnel blasting have stringent viscosity requirements. High viscosity makes spraying difficult, resulting in heavy droplets that struggle to capture fine dust particles and risk clogging the spraying equipment. Low viscosity results in poor dust suppression, making it difficult to capture and settle dust generated during blasting. Therefore, the optimal viscosity range for the prepared dust suppressant solution is 20mPa·s to 40Pa·s.

[0006] Therefore, it is necessary to propose a special dust suppressant for tunnel blasting conditions and a preparation method thereof to solve the above problems. Summary of the Invention

[0007] The purpose of the present invention is to provide a special dust suppressant for tunnel blasting conditions and a preparation method thereof, which can quickly and efficiently reduce dust during tunnel blasting construction, improve construction efficiency, and protect the health of workers.

[0008] In a first aspect, the present invention provides a special dust suppressant for tunnel blasting conditions, comprising component A and component B; The component A comprises the following raw materials in parts by weight: 2-4 parts of sodium carboxymethyl starch; 3-15 parts of 70% neutralized acrylic acid; Potassium persulfate 0.01-0.09 parts; Sodium bisulfite 0.01-0.06 parts; 0.01-0.15 parts of N,N'-methylenebisacrylamide; The component B is a surfactant, which is a mixture of one or more of isodecanol polyoxyethylene ether and fatty alcohol polyoxyethylene ether.

[0009] Furthermore, the mass ratio of component A to component B is 20-100:1.

[0010] In a second aspect, the present invention provides a method for preparing a special dust suppressant for tunnel blasting conditions, comprising: Step 1: Provide the following raw materials: component A and component B; component A comprises the following raw materials in parts by weight: 2-4 parts sodium carboxymethyl starch; 3-15 parts 70% neutralized acrylic acid; 0.01-0.09 parts potassium persulfate; 0.01-0.06 parts sodium bisulfite; and 0.01-0.15 parts N,N'-methylenebisacrylamide; component B is a surfactant, which is a mixture of one or more of isodecanol polyoxyethylene ether and fatty alcohol polyoxyethylene ether; Sodium carboxymethyl starch and 150 mL to 200 mL of deionized water were added to a beaker, heated and stirred, and gelatinized in a water bath for 40 min to 50 min to obtain a mixture 1; Step 2: Cool the mixture 1 to room temperature, add acrylic acid with a neutralization degree of 70% under the protection of nitrogen, and mix thoroughly for 15 minutes to 40 minutes to obtain a mixture 2; Step 3: Heat the mixture 2, add sodium bisulfite at a constant temperature under nitrogen protection, stir for 5-15 minutes, add potassium persulfate, and stir the reaction for 1.5-2.5 hours to obtain a mixture 3; Step 4: adding a cross-linking agent N,N'-methylenebisacrylamide to the mixture 3, and reacting at a constant temperature for 0.5h-1.5h under nitrogen protection to obtain a mixture 4; Step 5: Cool the mixture 4 to room temperature, add 95% ethanol, wash 2-3 times, dry, and crush into powder to obtain a mixture 5; Step six, taking part of the mixture five, adding a surfactant thereto, adding deionized water and mixing until completely dissolved, thereby obtaining a special dust suppressant for tunnel blasting conditions.

[0011] Furthermore, the heating temperature in step 1 is 40° C.-65° C., and the stirring rate is 1600-2400 rpm.

[0012] Furthermore, the constant temperature in step three is 45°C-65°C.

[0013] Furthermore, the drying temperature in step five is 40° C.-60° C., and the drying time is 12 h-24 h.

[0014] Furthermore, in step six, part of the mixture five is used as component A, the surfactant is used as component B, and the mass ratio of component A to component B is 20~100:1.

[0015] The present invention has the following beneficial effects: The graft copolymerization modification product using sodium carboxymethyl starch as a raw material can enhance the viscosity and coagulation effect of the dust suppressant; the initiator used is a redox system of sodium bisulfite and potassium persulfate, which significantly improves the grafting efficiency and speed at low temperatures, achieving high performance and low cost; N,N'-methylenebisacrylamide is used as a crosslinker, the main function of which is to enhance the film-forming properties, mechanical strength, durability, and environmental adaptability of the dust suppressant, and N,N'-methylenebisacrylamide can be used as a crosslinker to construct a three-dimensional polymer network structure. The reaction temperature of the graft copolymerization modification is controlled at 45°C-65°C, resulting in a simple process flow and convenient operation; the special dust suppressant synthesized through this series of process operations for tunnel blasting conditions can effectively improve the grafting rate and water absorption performance of the dust suppressant. The surfactants used, isodecanol polyoxyethylene ether and fatty alcohol polyoxyethylene ether, have a good effect of reducing surface tension, improve the wetting effect of the dust suppressant on dust, make the dust settle, and effectively improve the dust suppression effect; the preparation method of the present invention is simple, and the special dust suppressant under tunnel blasting conditions can greatly reduce dust during tunnel blasting, achieve dust reduction in a short time, facilitate tunnel construction, and improve construction efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solution of the present invention, the following briefly introduces the drawings required for use in the embodiments. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0017] Figure 1 This is a flow chart of the preparation method of the special dust suppressant for tunnel blasting conditions provided by the present invention. DETAILED DESCRIPTION

[0018] To make the objectives, technical solutions, and advantages of the present invention more clear, the technical solutions of the present invention will be clearly and completely described below in conjunction with specific embodiments of the present invention and corresponding drawings. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention. The technical solutions provided by each embodiment of the present invention are described in detail below in conjunction with the drawings.

[0019] See also Figure 1The present invention uses deionized water as a solvent, sodium carboxymethyl starch as a skeleton, acrylic acid as a monomer, sodium bisulfite and potassium persulfate redox system as an initiator, and then uses N,N'-methylenebisacrylamide as a monomer for synthesis. The obtained product is then compounded with a surfactant. The present invention is aimed at the synthesis of dust suppressants under tunnel construction blasting conditions. Therefore, the viscosity requirements are relatively strict. When the viscosity is high, it is not easy to spray, the sprayed droplets are heavy, and it is not easy to capture fine particles of dust. There is also a risk of clogging the spraying equipment. When the viscosity is too low, the dust suppression effect is not good, and the dust generated during blasting is not easy to be captured and precipitated. Therefore, the viscosity of the prepared dust suppressant solution needs to be within a certain range, and then by compounding with a surfactant, the wettability and permeability are enhanced to improve the dust capture efficiency. At the same time, the synthesized dust suppressant is formed by adding a cross-linking agent to form a polymer three-dimensional network structure, which can enhance the toughness of the solidified layer and make tunnel construction more convenient.

[0020] The present application provides a special dust suppressant for tunnel blasting conditions. The special dust suppressant comprises 2-4 parts of sodium carboxymethyl starch, 3-15 parts of 70% neutralized acrylic acid, 0.01-0.09 parts of potassium persulfate, 0.01-0.06 parts of sodium bisulfite, and 0.01-0.15 parts of N,N'-methylenebisacrylamide. The ratio of the synthesized surfactant component A to component B is 20-100:1.

[0021] Example 1: The special dust suppressant for tunnel blasting conditions includes, by weight, 3 parts of sodium carboxymethyl cellulose, 12.5 parts of 70% neutralized acrylic acid, 0.072 parts of potassium persulfate, 0.036 parts of sodium bisulfite, and 0.072 parts of N,N-methylenebisacrylamide. The ratio of the synthesized component A to component B surfactant is 20:1.

[0022] In this embodiment, the surfactant is fatty alcohol polyoxyethylene ether.

[0023] In this embodiment, a method for preparing a special dust suppressant for tunnel blasting conditions includes the following steps: 3 parts of sodium carboxymethyl starch and 150 mL of deionized water were added to a beaker, heated and stirred at 55° C. at a stirring rate of 2000 rpm, and gelatinized in a water bath for 50 min to obtain a mixture 1; The mixture 1 was slowly cooled to room temperature, and acrylic acid with a neutralization degree of 70% was added under the protection of nitrogen, and the mixture was thoroughly mixed for 30 minutes to obtain a mixture 2; The mixture 2 was heated to 60°C, sodium bisulfite was added while maintaining the temperature at 60°C, and the mixture was stirred for 10 minutes. Potassium persulfate was added and the mixture was reacted for 2 hours to obtain a mixture 3. Adding a crosslinking agent N,N'-methylenebisacrylamide to the mixture three, and reacting at a constant temperature for 1 hour to obtain a mixture four; The mixture 4 was cooled to room temperature, washed twice with 95% ethanol, dried at 55°C for 24 hours, and crushed into powder to obtain the mixture 5; Take a certain amount of mixture five, add fatty alcohol polyoxyethylene ether, add water to mix and dissolve, and then obtain a special dust suppressant for tunnel blasting conditions.

[0024] Example 2:

[0025] The special dust suppressant for tunnel blasting conditions includes, by weight, 3 parts of sodium carboxymethyl cellulose, 12.5 parts of 70% neutralized acrylic acid, 0.048 parts of potassium persulfate, 0.024 parts of sodium bisulfite, and 0.09 parts of N,N-methylenebisacrylamide. The ratio of the synthesized component A to component B surfactant is 20:1.

[0026] In this embodiment, the surfactant is isodecanol polyoxyethylene ether.

[0027] In this embodiment, a method for preparing a special dust suppressant for tunnel blasting conditions includes the following steps: Sodium carboxymethyl starch and 150 mL of deionized water were added to a beaker, heated and stirred at 55° C. at a stirring rate of 1800 rpm, and gelatinized in a water bath for 50 min to obtain a mixture 1; The mixture 1 was slowly cooled to room temperature, and acrylic acid with a neutralization degree of 70% was added under the protection of nitrogen, and the mixture was thoroughly mixed for 40 minutes to obtain a mixture 2; The mixture 2 was heated to 55°C, sodium bisulfite was added while maintaining the temperature at 55°C, and the mixture was stirred for 10 minutes. Potassium persulfate was added and the mixture was reacted for 2 hours to obtain a mixture 3. Adding a crosslinking agent N,N'-methylenebisacrylamide to the mixture three, and reacting at a constant temperature for 1 hour to obtain a mixture four; The mixture 4 was cooled to room temperature, washed three times with 95% ethanol, dried at 55°C for 24 hours, and crushed into powder to obtain the mixture 5; Take a certain amount of mixture five, add isodecanol polyoxyethylene ether, add water to mix and dissolve, and then obtain a special dust suppressant for tunnel blasting conditions.

[0028] Example 3:

[0029] The special dust suppressant for tunnel blasting conditions includes, by weight, 3 parts of sodium carboxymethyl cellulose, 12.5 parts of 70% neutralized acrylic acid, 0.048 parts of potassium persulfate, 0.024 parts of sodium bisulfite, and 0.09 parts of N,N-methylenebisacrylamide. The ratio of the synthesized component A to component B surfactant is 20:1.

[0030] In this embodiment, the surfactants used are fatty alcohol polyoxyethylene ether and isodecanol polyoxyethylene ether.

[0031] In this embodiment, a method for preparing a special dust suppressant for tunnel blasting conditions includes the following steps: Sodium carboxymethyl starch and 150 mL of deionized water were added to a beaker, heated and stirred at 55° C. at a stirring rate of 1800 rpm, and gelatinized in a water bath for 50 min to obtain a mixture 1; The mixture 1 was slowly cooled to room temperature, and acrylic acid with a neutralization degree of 70% was added under the protection of nitrogen, and the mixture was thoroughly mixed for 40 minutes to obtain a mixture 2; The mixture 2 was heated to 55°C, sodium bisulfite was added while maintaining the temperature at 55°C, and the mixture was stirred for 10 minutes. Potassium persulfate was added and the mixture was reacted for 2 hours to obtain a mixture 3. Adding a crosslinking agent N,N'-methylenebisacrylamide to the mixture three, and reacting at a constant temperature for 1 hour to obtain a mixture four; The mixture 4 was cooled to room temperature, washed three times with 95% ethanol, dried at 55°C for 24 hours, and crushed into powder to obtain the mixture 5; Take a certain amount of mixture five, add fatty alcohol polyoxyethylene ether and isodecanol polyoxyethylene ether in a mass ratio of 40:1:1, add water to mix and dissolve, and thus obtain a special dust suppressant for tunnel blasting conditions.

[0032] The dust suppressants prepared in Examples 1 to 3 of the present invention were used to perform performance tests, and the data obtained are shown in Table 1.

[0033] Table 1 Example effect analysis data table

[0034] According to the viscosity and surface tension data of the three embodiments in Table 1, it can be seen that the viscosity of the synthesized dust suppressant is 13 to 25 times that of the raw material sodium carboxymethyl starch, and the viscosity of the synthesized dust suppressant is significantly enhanced. By compounding the surfactant, it can be seen that compared with deionized water, the synthesized dust suppressant has a better effect of reducing surface tension, can improve the wetting effect of the dust suppressant on dust, can effectively reduce dust, and facilitate the implementation of the operation.

[0035] In summary, the preparation method of the present invention is simple, and the obtained special dust suppressant for tunnel blasting conditions has a significantly increased viscosity relative to the raw material sodium carboxymethyl starch. At the same time, compared with deionized water, it has a better effect of reducing surface tension, can improve the wetting effect of the dust suppressant on dust, can effectively reduce dust, and facilitate operation implementation.

[0036] The above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A special dust suppressant for tunnel blasting conditions, characterized in that: Comprising component A and component B; The component A comprises the following raw materials in parts by weight: 2-4 parts of sodium carboxymethyl starch; 3-15 parts of 70% neutralized acrylic acid; Potassium persulfate 0.01-0.09 parts; Sodium bisulfite 0.01-0.06 parts; 0.01-0.15 parts of N,N'-methylenebisacrylamide; The component B is a surfactant, which is a mixture of one or more of isodecanol polyoxyethylene ether and fatty alcohol polyoxyethylene ether.

2. The special dust suppressant for tunnel blasting according to claim 1, characterized in that: The mass ratio of component A to component B is 20~100:

1.

3. A method for preparing a special dust suppressant for tunnel blasting conditions, characterized in that: include: Step 1: Provide the following raw materials: component A and component B; component A comprises the following raw materials in parts by weight: 2-4 parts of sodium carboxymethyl starch; 3-15 parts of 70% neutralized acrylic acid; 0.01-0.09 parts of potassium persulfate; 0.01-0.06 parts of sodium bisulfite; 0.01-0.15 parts of N,N'-methylenebisacrylamide; the component B is a surfactant, which is a mixture of one or more of isodecanol polyoxyethylene ether and fatty alcohol polyoxyethylene ether; Sodium carboxymethyl starch and 150 mL to 200 mL of deionized water were added to a beaker, heated and stirred, and gelatinized in a water bath for 40 min to 50 min to obtain a mixture 1; Step 2: Cool the mixture 1 to room temperature, add acrylic acid with a neutralization degree of 70% under the protection of nitrogen, and mix thoroughly for 15 minutes to 40 minutes to obtain a mixture 2; Step 3: Heat the mixture 2, add sodium bisulfite at a constant temperature under nitrogen protection, stir for 5-15 minutes, add potassium persulfate, and stir the reaction for 1.5-2.5 hours to obtain a mixture 3; Step 4: adding a cross-linking agent N,N'-methylenebisacrylamide to the mixture 3, and reacting at a constant temperature for 0.5h-1.5h under nitrogen protection to obtain a mixture 4; Step 5: Cool the mixture 4 to room temperature, add 95% ethanol, wash 2-3 times, dry, and crush into powder to obtain a mixture 5; Step six, taking part of the mixture five, adding a surfactant thereto, adding deionized water and mixing until completely dissolved, thereby obtaining a special dust suppressant for tunnel blasting conditions.

4. The method for preparing a special dust suppressant for tunnel blasting according to claim 3, characterized in that: The heating temperature in the step 1 is 40° C.-65° C., and the stirring rate is 1600-2400 rpm.

5. The method for preparing a special dust suppressant for tunnel blasting according to claim 3, characterized in that: The constant temperature in step 3 is 45°C-65°C.

6. The method for preparing a special dust suppressant for tunnel blasting according to claim 3, characterized in that: The drying temperature in step 5 is 40° C.-60° C., and the drying time is 12 h-24 h.

7. The method for preparing a special dust suppressant for tunnel blasting according to claim 3, characterized in that: In step six, part of the mixture five is used as component A, the surfactant is used as component B, and the mass ratio of component A to component B is 20~100:1.

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