Preparation method of anti-seepage mixed emulsion explosive for fractured rock stratum

Abstract

The preparation method comprises the following steps: S1, preparing a water phase: weighing 78.6-78.9% by mass of ammonium nitrate, 15.1-15.4% by mass of water, 0.03-0.05% by mass of citric acid and 0.148-0.15% by mass of thiourea, mixing, heating to 95-100 DEG C, stirring until complete dissolution, adjusting the pH value of the system to 4.0-4.5, controlling the crystallization point of the water phase to be less than or equal to 68 DEG C, and preserving heat for later use; the oil phase is prepared from, by mass, 10%-20% of a compound emulsifier, 30%-40% of engine oil and 50%-60% of diesel oil, the compound emulsifier, the engine oil and the diesel oil are mixed and then heated to 80-90 DEG C, and the mixture is stirred to be uniform for standby application. Parameters such as emulsification rotating speed and temperature are compatible with an existing mixed loading production line, large-scale equipment transformation is not needed, and industrial popularization is easy.

Description

Technical Field

[0001] This invention relates to the field of emulsion explosive preparation technology, and in particular to a method for preparing anti-seepage mixed emulsion explosives for fractured rock strata. Background Technology

[0002] Mixed emulsion explosives are widely used in blasting operations in mining, water conservancy projects, and other fields due to their advantages such as good water resistance, excellent explosive performance, and low production cost. However, in fractured rock environments, existing mixed emulsion explosives generally suffer from insufficient matrix consistency and poor cohesion, leading to easy leakage along rock fissures after loading. This not only increases explosive consumption and blasting costs but may also affect blasting effectiveness due to uneven explosive distribution, and even cause safety hazards.

[0003] In existing technologies, improvements to mixed emulsion explosives mainly focus on storage stability and detonation velocity enhancement, such as improving stability by optimizing the emulsifier structure or enhancing detonation performance by adjusting the sensitization process. However, there are few technical solutions specifically addressing the anti-leakage requirements of fractured rock formations. Furthermore, blasting in fractured rock formations often faces complex conditions, such as low-temperature environments and storage requirements. Existing anti-leakage technologies often struggle to simultaneously achieve multiple performance indicators, including anti-leakage, detonation velocity, low-temperature resistance, and storage stability. Therefore, developing a method for preparing mixed emulsion explosives that combines high anti-leakage, excellent explosive performance, and environmental adaptability is crucial for solving the challenges of blasting in fractured rock formations. Summary of the Invention

[0004] The purpose of this invention is to address the shortcomings of existing technologies by proposing a method for preparing anti-seepage mixed emulsion explosives for fractured rock strata.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: A method for preparing a mixed emulsion explosive for preventing seepage in fractured rock formations includes the following steps: S1. Preparation of aqueous phase: Weigh out 78.6-78.9% ammonium nitrate, 15.1-15.4% water, 0.03-0.05% citric acid, and 0.148-0.15% thiourea by mass fraction. Mix them and heat to 95-100℃, stirring until completely dissolved. Adjust the pH of the system to 4.0-4.5 and control the crystallization point of the aqueous phase to ≤68℃. Keep warm for later use. S2. Oil phase preparation: The oil phase is composed of composite emulsifier, engine oil and diesel oil in a certain mass fraction ratio, wherein the composite emulsifier accounts for 10-20% of the total mass of the oil phase, the engine oil accounts for 30-40% of the total mass of the oil phase, and the diesel oil accounts for 50-60% of the total mass of the oil phase. After mixing the composite emulsifier, engine oil and diesel oil, heat to 80-90℃ and stir evenly for later use. S3. Emulsification reaction: The aqueous phase, after being kept at a constant temperature, is slowly added to the oil phase at a mass ratio of 94:6. The initial stirring speed is 400-600 r / min. After the aqueous phase is completely added, the speed is adjusted to 1100 r / min, and emulsification is continued for 2 minutes to obtain the latex matrix. The emulsification process adopts a single-stage emulsification method. The emulsifier operates at a speed of 1460 r / min, the discharge temperature is controlled at 70-80℃, and the production line operating pressure is maintained at about 0.5 MPa. S4. Sensitization treatment: Cool the latex matrix to the sensitization temperature, where the sensitization temperature at room temperature is 50-65℃ and the sensitization temperature in winter is 40-55℃; add sodium nitrite sensitizer with a concentration of 20-25%, the amount of which is 0.4-0.6‰ of the total mass of the explosive matrix, and continue stirring for sensitization for 15-20 minutes. After sensitization, the explosive is free of large air bubbles and the sensitization is uniform, thus obtaining the anti-seepage mixed emulsion explosive for fractured rock strata.

[0006] Preferably, in step S1, the amount of citric acid added is 0.04%, the amount of thiourea added is 0.148%, the pH value of the aqueous phase is controlled at 4.2-4.3, and the crystallization point is controlled at 66-68℃.

[0007] Preferably, in step S2, the composite emulsifier is Span-80, a compound of the reaction product of polyisobutylene succinic anhydride and N,N-dimethylethanolamine. The molar ratio of polyisobutylene succinic anhydride to N,N-dimethylethanolamine is 1:2. The reaction temperature is controlled at 160°C, and the reaction time is 6 hours. During the reaction, SN150 base oil accounting for 60-70% of the mass of polyisobutylene succinic anhydride is added, and a 30% concentration sodium hydroxide aqueous solution accounting for 0.05-0.1% of the total mass of the reaction system is added as a catalyst. In the composite emulsifier, the mass ratio of the reaction product of polyisobutylene succinic anhydride and N,N-dimethylethanolamine to Span-80 is 8:2. Preferably, the polyisobutylene succinic anhydride has a molecular weight of 1000, and the amount of SN150 base oil added is 65% of the mass of the polyisobutylene succinic anhydride.

[0008] Preferably, the amount of sodium hydroxide catalyst added is 0.08% of the total mass of the reaction system, and a 30% sodium hydroxide aqueous solution is slowly added dropwise to the reaction system at 90-95°C.

[0009] Preferably, in step S2, the engine oil is 46# engine oil and the diesel oil is 0# diesel oil; the total amount of composite emulsifier added accounts for 1.6-1.7% of the total mass of the explosive matrix, wherein the reaction product of polyisobutylene succinic anhydride and N,N-dimethylethanolamine accounts for 80-85% of the total mass of the composite emulsifier.

[0010] Preferably, in step S4, the concentration of sodium nitrite sensitizer is 22%, the addition amount at room temperature is 0.5‰, the addition amount in winter is 0.6‰, and the sensitization stirring speed is 800-1000 r / min.

[0011] Preferably, in step S3, the aqueous phase is added at a rate of 5-8 mL / s, and nitrogen protection is used during the emulsification process, with a nitrogen introduction rate of 0.5-1 L / min, to prevent the oil phase from oxidizing and deteriorating.

[0012] Compared with the prior art, the beneficial effects of the present invention are: 1. In this invention, by increasing the proportion of engine oil and the cohesive effect of composite emulsifier, the consistency of the latex matrix is ​​improved, the leakage in the fractured rock layer is reduced, and the consumption of explosives is reduced. 2. The invention features a high detonation velocity, a significant improvement over existing products, and enhanced blasting power, making it suitable for breaking up complex fractured rock strata. 3. The invention has a longer shelf life at room temperature, no demulsification or crystallization, and is suitable for blasting operations in different regions and seasons. 4. In this invention, parameters such as emulsification speed and temperature are compatible with existing mixing production lines, requiring no large-scale equipment modification and making it easy to promote industrialization. Attached Figure Description

[0013] Figure 1 This is a flowchart of a method for preparing anti-seepage mixed emulsion explosives for fractured rock strata, as proposed in this invention. Detailed Implementation

[0014] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0015] Reference Figure 1 A method for preparing anti-seepage mixed emulsion explosives for fractured rock strata includes the following steps: S1. Preparation of aqueous phase: Weigh out 78.6-78.9% ammonium nitrate, 15.1-15.4% water, 0.03-0.05% citric acid, and 0.148-0.15% thiourea by mass fraction. Mix them and heat to 95-100℃, stirring until completely dissolved. Adjust the pH of the system to 4.0-4.5 and control the crystallization point of the aqueous phase to ≤68℃. Keep warm for later use. S2. Oil phase preparation: The oil phase is composed of composite emulsifier, engine oil and diesel oil in a certain mass fraction ratio, wherein the composite emulsifier accounts for 10-20% of the total mass of the oil phase, the engine oil accounts for 30-40% of the total mass of the oil phase, and the diesel oil accounts for 50-60% of the total mass of the oil phase. After mixing the composite emulsifier, engine oil and diesel oil, heat to 80-90℃ and stir evenly for later use. S3. Emulsification reaction: The aqueous phase, after being kept at a constant temperature, is slowly added to the oil phase at a mass ratio of 94:6. The initial stirring speed is 400-600 r / min. After the aqueous phase is completely added, the speed is adjusted to 1100 r / min, and emulsification is continued for 2 minutes to obtain the latex matrix. The emulsification process adopts a single-stage emulsification method. The emulsifier operates at a speed of 1460 r / min, the discharge temperature is controlled at 70-80℃, and the production line operating pressure is maintained at about 0.5 MPa. S4. Sensitization treatment: Cool the latex matrix to the sensitization temperature, where the sensitization temperature at room temperature is 50-65℃ and the sensitization temperature in winter is 40-55℃; add sodium nitrite sensitizer with a concentration of 20-25%, the amount of which is 0.4-0.6‰ of the total mass of the explosive matrix, and continue stirring for sensitization for 15-20 minutes. After sensitization, the explosive is free of large air bubbles and the sensitization is uniform, thus obtaining the anti-seepage mixed emulsion explosive for fractured rock strata.

[0016] In step S1, the amount of citric acid added is 0.04%, the amount of thiourea added is 0.148%, the pH value of the aqueous phase is controlled at 4.2-4.3, and the crystallization point is controlled at 66-68℃.

[0017] In step S2, the composite emulsifier is Span-80, a compound of the reaction product of polyisobutylene succinic anhydride and N,N-dimethylethanolamine. The molar ratio of polyisobutylene succinic anhydride to N,N-dimethylethanolamine is 1:2. The reaction temperature is controlled at 160℃, and the reaction time is 6h. During the reaction, SN150 base oil accounting for 60-70% of the mass of polyisobutylene succinic anhydride is added, and a 30% concentration sodium hydroxide aqueous solution accounting for 0.05-0.1% of the total mass of the reaction system is added as a catalyst. In the composite emulsifier, the mass ratio of the reaction product of polyisobutylene succinic anhydride and N,N-dimethylethanolamine to Span-80 is 8:2. The molecular weight of polyisobutylene succinic anhydride is 1000, and the amount of SN150 base oil added is 65% of the mass of polyisobutylene succinic anhydride.

[0018] The amount of sodium hydroxide catalyst added is 0.08% of the total mass of the reaction system, and a 30% sodium hydroxide aqueous solution is slowly added dropwise to the reaction system at 90-95℃.

[0019] In step S2, the engine oil is 46# engine oil and the diesel oil is 0# diesel oil; the total amount of composite emulsifier added accounts for 1.6-1.7% of the total mass of the explosive matrix, of which the reaction product of polyisobutylene succinic anhydride and N,N-dimethylethanolamine accounts for 80-85% of the total mass of the composite emulsifier.

[0020] In step S4, the concentration of sodium nitrite sensitizer is 22%, the addition amount at room temperature is 0.5‰, the addition amount in winter is 0.6‰, and the sensitization stirring speed is 800-1000 r / min.

[0021] In step S3, the aqueous phase is added at a rate of 5-8 mL / s, and nitrogen is used for protection during emulsification at a rate of 0.5-1 L / min to prevent the oil phase from oxidizing and deteriorating.

[0022] In this invention, by increasing the proportion of engine oil and the cohesive effect of the composite emulsifier, the consistency of the latex matrix is ​​improved, the leakage in fractured rock strata is reduced, and the consumption of explosives is reduced; the detonation velocity is fast, which is significantly improved compared with existing products, and the blasting power is enhanced, which can meet the crushing requirements of complex fractured rock strata; the storage period at room temperature is longer, there is no demulsification and crystallization phenomenon, and it is suitable for blasting operations in different regions and seasons; the emulsification speed, temperature and other parameters are compatible with existing mixed production lines, without the need for large-scale equipment modification, and are easy to promote industrially.

[0023] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A method for preparing a leak-resistant mixed emulsion explosive for a fractured rock formation, characterized by, It comprises the following steps: S1, water phase preparation: according to the mass fraction, ammonium nitrate 78.6-78.9%, water 15.1-15.4%, citric acid 0.03-0.05%, and thiourea 0.148-0.15% are weighed, mixed and heated to 95-100℃, stirred until completely dissolved, the pH value of the system is adjusted to 4.0-4.5, the water phase crystallization point is controlled to be less than or equal to 68℃, and the system is kept warm for standby; S2, oil phase preparation: the oil phase is composed of complex emulsifier, machine oil and diesel oil according to the mass fraction, wherein the complex emulsifier accounts for 10-20% of the total mass of the oil phase, the machine oil accounts for 30-40% of the total mass of the oil phase, and the diesel oil accounts for 50-60% of the total mass of the oil phase, the complex emulsifier, machine oil and diesel oil are mixed and heated to 80-90℃, and then uniformly stirred for standby; S3, emulsification reaction: the water phase is slowly added into the oil phase according to the mass ratio of water phase to oil phase of 94:6, the initial stirring speed is 400-600r / min, the stirring speed is adjusted to 1100r / min after the water phase is completely added, and the emulsion base is prepared by continuously emulsifying for 2min; the emulsification process adopts primary emulsification mode, the working speed of the emulsifier is 1460r / min, the drug outlet temperature is controlled at 70-80℃, and the production line operating pressure is maintained at about 0.5MPa; S4, sensitization treatment: the emulsion base is cooled to the sensitization temperature, wherein the normal temperature sensitization temperature is 50-65℃, and the winter sensitization temperature is 40-55℃; the sensitization agent of 20-25% sodium nitrite is added, the addition amount is 0.4-0.6‰ of the total mass of the explosive base, the sensitization is continuously stirred for 15-20min, and the anti-leakage mixed loading emulsion explosive for fractured rock stratum is obtained after the sensitization of the explosive without air bubbles.

2. The preparation method of the anti-leakage mixed emulsion explosive for fractured rock stratum according to claim 1, characterized in that, In the step S1, the addition amount of citric acid is 0.04%, the addition amount of thiourea is 0.148%, the pH value of the water phase is controlled to be 4.2-4.3, and the crystallization point is controlled to be 66-68℃.

3. The preparation method of the anti-leakage mixed emulsion explosive for fractured rock stratum according to claim 1, characterized in that, In the step S2, the complex emulsifier is the reaction product of polyisobutylene succinic anhydride and N,N-dimethyl ethanolamine compounded with Span-80, the reaction molar ratio of polyisobutylene succinic anhydride to N,N-dimethyl ethanolamine is 1:2, the reaction temperature is controlled to be 160℃, the reaction time is 6h, 60-70% of SN150 base oil of the mass of polyisobutylene succinic anhydride is added during the reaction, and 0.05-0.1% of 30% sodium hydroxide aqueous solution of the total mass of the reaction system is added as a catalyst; in the complex emulsifier, the mass ratio of the reaction product of polyisobutylene succinic anhydride and N,N-dimethyl ethanolamine to Span-80 is 8:

2.

4. The preparation method of the anti-leakage mixed emulsion explosive for fractured rock stratum according to claim 3, characterized in that, The molecular weight of the polyisobutylene succinic anhydride is 1000, and the addition amount of the SN150 base oil is 65% of the mass of the polyisobutylene succinic anhydride.

5. The method of claim 3, wherein the method further comprises: The addition amount of the sodium hydroxide catalyst is 0.08% of the total mass of the reaction system, and the 30% sodium hydroxide aqueous solution is slowly added into the reaction system at 90-95℃. ​ 6. The method of claim 3, wherein the method further comprises: In the step S2, the machine oil is 46# machine oil, the diesel oil is 0# diesel oil; the total adding amount of the compound emulsifier accounts for 1.6-1.7% of the total mass of the explosive matrix, wherein the reaction product of polyisobutylene succinic anhydride and N,N-dimethylethanolamine accounts for 80-85% of the total mass of the compound emulsifier. ​ 7. The method of claim 1, wherein the method further comprises: adding the water to the emulsion to form the emulsion, and adding the emulsion to the slurry to form the emulsion-in-slurry explosive. 7 In the step S4, the concentration of the sodium nitrite sensitizer is 22%, the adding amount at normal temperature is 0.5‰, the adding amount in winter is 0.6‰, and the stirring speed of sensitization is 800-1000 r / min.

8. The method for preparing a mixed emulsion explosive for preventing seepage in fractured rock formations according to claim 1, characterized in that, In the step S3, the adding speed of the water phase is 5-8 mL / s, nitrogen protection is adopted in the emulsification process, the nitrogen inlet rate is 0.5-1 L / min, and the oxidation deterioration of the oil phase is avoided.

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