A high-temperature resistant downhole emulsion explosive and its preparation method
By adding urea and chitosan quaternary ammonium salt to emulsion explosives, optimizing the oil phase material formulation, and using composite emulsifiers and stabilizers, the thermal stability problem of emulsion explosives under high-temperature environments was solved, ensuring the blasting effect.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-04-15
- Publication Date
- 2026-06-26
AI Technical Summary
Existing emulsion explosives have poor thermal stability at high temperatures, leading to oil-water phase separation, demulsification failure, and severely reducing the explosive's initiation sensitivity and detonation propagation performance.
Urea and chitosan quaternary ammonium salt are added to the aqueous phase of the emulsion explosive, and the oil phase material formulation is optimized by using composite emulsifiers, including Span80 and polyisobutylene succinimide derivatives, and thiolated long-chain alkyl phosphates are added as stabilizers to enhance the thermal stability and interfacial film strength of the emulsion.
It improves the stability of emulsion explosives at high temperatures, inhibits oil-water phase separation, ensures blasting effect, and maintains explosive performance in high-temperature environments.
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Abstract
Description
Technical Field
[0001] This invention belongs to the field of emulsion explosives technology, specifically relating to a high-temperature resistant downhole emulsion explosive and its preparation method. Background Technology
[0002] Emulsion explosives are a special type of aqueous mixed explosive. Their key components include an aqueous oxidant solution as the dispersed phase and a water-insoluble but liquefiable carbonaceous fuel as the continuous phase. Through the synergistic effect of emulsification and sensitizers, a unique water-in-oil structure is formed. This type of explosive has several significant characteristics: a wide density adjustment range, high detonation velocity and saturation, excellent initiation sensitivity, and outstanding water resistance.
[0003] Mining is the largest and most traditional application market for emulsion explosives, accounting for the majority of global demand. The use of emulsion explosives in mines can significantly improve mining efficiency. However, in special operating environments such as deep well mining or geothermal drilling, the underground temperature often reaches 80°C to 180°C or even higher. Conventional emulsion explosives face severe challenges. Under high-temperature conditions, the microstructure of the emulsion is easily damaged, leading to oil-water phase separation, demulsification failure, and severely reducing the explosive's initiation sensitivity and detonation transmission performance. Therefore, there is an urgent need to develop an emulsion explosive that combines excellent thermal stability, reliable safety, and adaptability to high-temperature and high-pressure underground environments. Summary of the Invention
[0004] This invention provides a high-temperature resistant downhole emulsion explosive and its preparation method, which can solve the problem of poor thermal stability of existing emulsion explosives.
[0005] The objective of this invention can be achieved through the following technical solutions: A high-temperature resistant downhole emulsion explosive comprises an aqueous phase material, an oil phase material, and a sensitizer, wherein the mass ratio of the three components is (88-96):(4-12):(0.8-2.0). The aqueous phase material, by mass parts, includes the following raw materials: Ammonium nitrate 70-80 parts, sodium nitrate 4-6 parts, urea 5-8 parts, chitosan quaternary ammonium salt 0.1-0.6 parts, water 10-20 parts; The oil phase material, by mass parts, includes the following raw materials: 50-70 parts of composite oil phase and 20-40 parts of composite emulsifier; The composite emulsifier includes Span80 and polyisobutylene succinimide derivatives; The structural formula of the polyisobutylene succinimide derivative is as follows:
[0006] Where R1 is or ; This invention adds urea and chitosan quaternary ammonium salt to the aqueous phase of emulsion explosives. On the one hand, adding urea to ammonium nitrate can effectively inhibit its decomposition and improve its thermal stability. On the other hand, the quaternary ammonium salt ions of chitosan quaternary ammonium salt have strong ionic interactions with nitrate ions, which can inhibit the crystallization of ammonium nitrate and avoid demulsification. Although the solubility of chitosan quaternary ammonium salt in water is higher than that of ordinary chitosan, its solubility is still limited. When urea is added simultaneously, urea molecules can form strong hydrogen bonds with the hydroxyl and amino groups on the chitosan molecular chain, thereby breaking the original hydrogen bond network structure inside chitosan and promoting the dissolution of chitosan quaternary ammonium salt in water. At this time, chitosan quaternary ammonium salt can slightly thicken the aqueous phase, so that the emulsified aqueous phase droplets maintain a stable structure and inhibit water evaporation and phase separation.
[0007] This invention optimizes the formulation of oil-phase materials by using a composite emulsifier to improve emulsification. The composite emulsifier includes Span80 and a polyisobutylene succinimide derivative. Span80 is a low molecular weight nonionic surfactant with good oil solubility due to its lipophilic group, making it easy to emulsify. However, it has poor high-temperature stability, and the double bonds in its molecule are easily oxidized at high temperatures, leading to demulsification. Simultaneously, a polyisobutylene succinimide derivative is added. This derivative contains lipophilic macromolecular long-chain polyisobutylene with good thermal stability, and also contains polyhydroxyl groups introduced by glucoheponic acid lactone, which has strong hydrophilicity and can be adsorbed onto the aqueous phase surface. The lipophilic groups form a protective film on the outside. The polyisobutylene succinimide derivative's molecular structure contains not only ester bonds but also imide bonds. The imide bonds have strong polarity and can form strong hydrogen bonds with chitosan quaternary ammonium salt in the aqueous phase, enhancing the chemical adsorption of the oil phase on the aqueous phase surface and improving the stability of the emulsion droplets at high temperatures. The addition of thiolized long-chain alkyl phosphate to the oil phase material allows the stabilizer to be uniformly dispersed in the oil phase in the presence of long-chain alkyl groups. The thiol groups at the molecular ends are polar and can react with unsaturated double bonds in the oil phase to crosslink, thereby enhancing the oil film strength, inhibiting demulsification caused by molecular motion at high temperatures, and preventing the microstructure of the emulsion from being easily destroyed.
[0008] Furthermore, the composite oil phase includes composite wax, microcrystalline wax and engine oil, with a mass ratio of (10-20):(15-25):(10-20).
[0009] Furthermore, the mass ratio of Span80 to polyisobutylene succinimide derivative in the composite emulsifier is 1:(0.4-0.7).
[0010] Furthermore, the preparation steps of the polyisobutylene succinimide derivative are as follows: A1. Add polyisobutylene succinic anhydride to the flask, install a reflux separator on the flask, add n-octane as a solvent, and stir until completely dissolved. A2. Heat the system to 60-80℃, add 2,2'-((2-aminoethyl)azadiyl)bis(ethanol-1-ol), heat to 95-100℃, stir the reaction for 8-10 hours, remove the solvent by rotary evaporation after the reaction is completed, and dry under vacuum to obtain the intermediate product. A3. Add the intermediate product and xylene to the flask, which is equipped with a reflux separator. Stir to dissolve and then heat to 80-90℃. A4. While stirring, add glucohepatic lactone to the system in step A3. After the addition is complete, heat to 110-120℃ and continue stirring to react. Take a sample during the reaction to determine the acid value. Stop the reaction when the acid value remains unchanged. A5. Extract the product of step A4 with saturated brine to remove unreacted substances, and then remove the solvent by rotary evaporation of the organic phase to obtain the product.
[0011] The reaction formula for the above preparation is as follows:
[0012]
[0013] Where R1 is or .
[0014] Using polyisobutylene succinic anhydride as the raw material, with an anhydride group at the end, 2,2'-((2-aminoethyl)azadiyl)bis(ethylene-1-ol) is another reactant, which contains an amino group and two hydroxyl groups at the end. The anhydride group reacts with the primary amine group to form an imide bond, the succinic anhydride ring-opens and reacts with the hydroxyl group to form an ester bond and a carboxyl group, and n-octane and water form an azeotrope. The generated water is removed by a reflux water separator to promote the reaction. Two hydroxyl groups are introduced into two polyisobutylene carboxyl molecular chains through an esterification reaction. The terminal carboxyl groups react with polyhydroxy glucohepanoic acid lactone through esterification. During the reaction, xylene and water form an azeotrope. A reflux water separator continuously removes water, which can both promote the reaction and inhibit the hydrolysis of lactone. Finally, a tertiary amine nitrogen atom is formed to connect a polyisobutylene succinimide and two polyisobutylene succinate multi-arm derivatives, so that its hydrophilic group can fully contact the aqueous phase and its lipophilic group can fully contact the oil phase, thereby enhancing the emulsification effect, strengthening the interfacial film, connecting the oil film and the aqueous phase, and resisting high-temperature demulsification.
[0015] Furthermore, the polyisobutylene succinic anhydride is prepared from highly reactive polyisobutylene with a molecular weight of 1000 and an acid value ≥70mgKOH / g.
[0016] Furthermore, the molar ratio of the polyisobutylene succinic anhydride and 2,2'-((2-aminoethyl)azadiyl)bis(ethanol-1-ol) is 3.00:1.05-1.10.
[0017] Furthermore, the mass ratio of the intermediate product to glucoheponic acid lactone is 1:(0.12-0.13).
[0018] Furthermore, the oil phase material also includes a stabilizer, wherein the stabilizer comprises 0.2-1.2 parts by mass.
[0019] Furthermore, the stabilizer is one of 11-mercaptoundecylphosphonic acid and 12-mercaptododecylphosphonic acid.
[0020] Furthermore, the sensitizer is one of hollow glass microspheres and expanded perlite. The use of a physical sensitizer provides better heat resistance, preventing the hollow structure from easily decomposing and collapsing at high temperatures, thus maintaining its function as a hotspot.
[0021] This invention also provides a method for preparing a high-temperature resistant downhole emulsion explosive, which includes the following steps: Step 1: Mix ammonium nitrate, sodium nitrate, urea, chitosan quaternary ammonium salt with water to obtain an aqueous phase material; Step 2: Heat the composite oil phase to 100-110℃, mix it well, add the other raw materials in the oil phase, stir and mix well to obtain the oil phase material; Step 3: Add the aqueous phase material to the oil phase material according to the mass ratio, heat to 100-130℃ for emulsification and homogenization to obtain the emulsified matrix; Step 4: Add the sensitizer to the emulsion matrix at room temperature and stir to obtain the emulsion explosive.
[0022] The beneficial effects of this invention are: (1) Based on the application of downhole emulsion explosives, the present invention designs and optimizes the formula by adding urea and chitosan quaternary ammonium salt to the aqueous phase of the emulsion explosive. Urea is used to inhibit the thermal decomposition of ammonium nitrate, improve the thermal stability of nitrate oxidizer, and ensure the blasting effect. Chitosan quaternary ammonium salt inhibits the crystallization of ammonium nitrate through the interionic interaction with ammonium nitrate, reducing the risk of demulsification caused by crystallization. Urea can destroy the intramolecular hydrogen bond network of chitosan and promote the dissolution of chitosan quaternary ammonium salt in the aqueous phase. With a slight increase in the viscosity of the aqueous phase, it can stabilize the emulsion droplet structure and inhibit oil-water separation at high temperature, thereby improving the stability of emulsion explosives under high temperature environment.
[0023] (2) The present invention simultaneously optimizes the oil phase formulation and adds a composite emulsifier to the composite oil phase. The composite emulsifier includes Span80 and polyisobutylene succinimide derivative. The polyisobutylene succinimide derivative is synthesized by independent design. Span80 provides a beneficial emulsifying effect. The polyisobutylene succinimide derivative has a multi-arm molecular chain structure. It is formed by reacting polyisobutylene succinic anhydride with 2,2'-((2-aminoethyl)azadiyl)bis(ethanol-1-ol), reacting succinic anhydride with primary amine and hydroxyl groups respectively, and then esterifying the product with glucoheponic acid lactone. Finally, a multi-arm derivative is formed with a tertiary amine nitrogen atom connecting a polyisobutylene succinimide and two polyisobutylene succinates. The polyisobutylene succinimide derivative has excellent thermal stability. It contains hydrophilic chains with multiple hydroxyl groups and long lipophilic chains of polyisobutylene, which can form a strong interfacial adsorption film at the oil-water interface, enhancing the interfacial strength and stability of the emulsion droplets at high temperatures.
[0024] (3) In this invention, a stabilizer is added to the oil phase simultaneously. The stabilizer is a mercapto-modified long-chain alkyl phosphate. The long-chain alkyl of the stabilizer makes it uniformly dispersed in the oil phase. The mercapto groups at the end of the molecular chain can cross-link with the unsaturated bonds of other raw materials in the oil phase, strengthen the network structure of the continuous phase of the oil phase, enhance the mechanical strength of the oil film, and jointly inhibit the destruction of the emulsion structure caused by the molecular thermal motion caused by high temperature, thus solving the high-temperature instability caused by the presence of unsaturated double bonds in the oil phase. Detailed Implementation
[0025] 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 of ordinary skill in the art without creative effort are within the scope of protection of the present invention.
[0026] Example 1 Preparation of polyisobutylene succinimide derivatives: A1. Add polyisobutylene succinic anhydride to a flask equipped with a reflux separator, add n-octane as a solvent, and the mass ratio of polyisobutylene succinic anhydride to n-octane is 1:1.5. Stir until completely dissolved.
[0027] A2. The system was heated to 70°C, and 2,2'-((2-aminoethyl)azadiyl)bis(ethylene-1-ol), polyisobutylene succinic anhydride and 2,2'-((2-aminoethyl)azadiyl)bis(ethylene-1-ol) in a molar ratio of 3.00:1.06 were added. The temperature was raised to 95°C, and the reaction was stirred for 10 h. After the reaction was completed, the solvent was removed by rotary evaporation, and the intermediate product was obtained by vacuum drying.
[0028] A3. Add the intermediate product and xylene to the flask at a mass ratio of 1:2. The flask is equipped with a reflux separator. After stirring and dissolving, heat to 90°C.
[0029] A4. While stirring, add glucohepatic lactone to the system of step A3. The mass ratio of intermediate product to glucohepatic lactone is 1:0.12. After the addition is complete, heat to 110℃ and continue stirring to react. Take a sample during the reaction to determine the acid value. Stop the reaction after the acid value remains unchanged.
[0030] A5. Extract the product of step A4 with saturated brine to remove unreacted substances, and then remove the solvent by rotary evaporation of the organic phase to obtain the product.
[0031] Preparation of high-temperature resistant downhole emulsion explosives: Step 1: Prepare the aqueous phase material according to the mass proportions. Mix 75 parts ammonium nitrate, 5 parts sodium nitrate, 6 parts urea, 0.4 parts chitosan quaternary ammonium salt and 14.6 parts water to obtain the aqueous phase material.
[0032] Step 2: Prepare the oil phase material according to the mass proportions. Add 20 parts of composite wax, 20 parts of microcrystalline wax and 20 parts of machine oil to a container, heat to 110℃, melt and stir until well mixed, add 20 parts of Span80 and 10 parts of polyisobutylene succinimide derivative, stir and mix until well mixed to obtain the oil phase material.
[0033] Step 3: Add the aqueous phase material to the oil phase material at a mass ratio of 90:10, heat to 120℃ for emulsification and homogenization to obtain the emulsified matrix.
[0034] Step 4: Add hollow glass microspheres to the emulsion matrix at room temperature. The mass ratio of hollow glass microspheres to aqueous phase material is 1.6:90. Stir for 20 minutes to obtain emulsion explosive.
[0035] Example 2 The only difference from Example 1 is that the mass fraction of chitosan quaternary ammonium salt in the aqueous phase material of the emulsion explosive is adjusted to 0.6 parts, while the other conditions and steps are the same as in Example 1.
[0036] Example 3 The only difference from Example 1 is that the mass fraction of chitosan quaternary ammonium salt in the aqueous phase material of the emulsion explosive is adjusted to 0.1 parts, while the other conditions and steps are the same as in Example 1.
[0037] Example 4 The only difference from Example 1 is that the mass fraction of Span80 in the oil phase material of the emulsion explosive is adjusted to 21.4 parts, and the mass fraction of polyisobutylene succinimide derivative is adjusted to 8.6 parts. Other conditions and steps are the same as in Example 1.
[0038] Example 5 The only difference from Example 1 is that the mass fraction of Span80 in the oil phase material of the emulsion explosive is adjusted to 17.7 parts, and the mass fraction of polyisobutylene succinimide derivative is adjusted to 12.3 parts. Other conditions and steps are the same as in Example 1.
[0039] Example 6 The only difference from Example 1 is that 0.8 parts of 11-mercaptoundecyl phosphate are added to the oil phase material as a stabilizer.
[0040] The conditions and steps for preparing the polyisobutylene succinimide derivative are the same as in Example 1.
[0041] Preparation of high-temperature resistant downhole emulsion explosives: Step 1: Prepare the aqueous phase material according to the mass proportions. Mix 75 parts ammonium nitrate, 5 parts sodium nitrate, 6 parts urea, 0.4 parts chitosan quaternary ammonium salt and 14.6 parts water to obtain the aqueous phase material.
[0042] Step 2: Prepare the oil phase material according to the mass proportions. Add 20 parts of composite wax, 20 parts of microcrystalline wax and 20 parts of machine oil to a container, heat to 110℃, melt and stir until well mixed. Add 20 parts of Span80, 10 parts of polyisobutylene succinimide derivative and 0.8 parts of 11-mercaptoundecyl phosphoric acid, stir and mix until well mixed to obtain the oil phase material.
[0043] Step 3: Add the aqueous phase material to the oil phase material at a mass ratio of 90:10, heat to 120℃ for emulsification and homogenization to obtain the emulsified matrix.
[0044] Step 4: Add hollow glass microspheres to the emulsion matrix at room temperature. The mass ratio of hollow glass microspheres to aqueous phase material is 1.6:90. Stir for 20 minutes to obtain emulsion explosive.
[0045] Example 7 The only difference from Example 1 is that 0.2 parts of 11-mercaptoundecylphosphonic acid are added to the oil phase material as a stabilizer.
[0046] The conditions and steps for preparing the polyisobutylene succinimide derivative are the same as in Example 1.
[0047] Preparation of high-temperature resistant downhole emulsion explosives: Step 1: Prepare the aqueous phase material according to the mass proportions. Mix 75 parts ammonium nitrate, 5 parts sodium nitrate, 6 parts urea, 0.4 parts chitosan quaternary ammonium salt and 14.6 parts water to obtain the aqueous phase material.
[0048] Step 2: Prepare the oil phase material according to the mass proportions. Add 20 parts of composite wax, 20 parts of microcrystalline wax and 20 parts of machine oil to a container, heat to 110℃, melt and stir until well mixed. Add 20 parts of Span80, 10 parts of polyisobutylene succinimide derivative and 0.2 parts of 11-mercaptoundecyl phosphoric acid, stir and mix until well mixed to obtain the oil phase material.
[0049] Step 3: Add the aqueous phase material to the oil phase material at a mass ratio of 90:10, heat to 120℃ for emulsification and homogenization to obtain the emulsified matrix.
[0050] Step 4: Add hollow glass microspheres to the emulsion matrix at room temperature. The mass ratio of hollow glass microspheres to aqueous phase material is 1.6:90. Stir for 20 minutes to obtain emulsion explosive.
[0051] Example 8 The only difference from Example 1 is that 1.2 parts of 11-mercaptoundecyl phosphate are added to the oil phase material as a stabilizer.
[0052] The conditions and steps for preparing the polyisobutylene succinimide derivative are the same as in Example 1.
[0053] Preparation of high-temperature resistant downhole emulsion explosives: Step 1: Prepare the aqueous phase material according to the mass proportions. Mix 75 parts ammonium nitrate, 5 parts sodium nitrate, 6 parts urea, 0.4 parts chitosan quaternary ammonium salt and 14.6 parts water to obtain the aqueous phase material.
[0054] Step 2: Prepare the oil phase material according to the mass proportions. Add 20 parts of composite wax, 20 parts of microcrystalline wax and 20 parts of machine oil to a container, heat to 110℃, melt and stir until well mixed. Add 20 parts of Span80, 10 parts of polyisobutylene succinimide derivative and 1.2 parts of 11-mercaptoundecyl phosphoric acid, stir and mix until well mixed to obtain the oil phase material.
[0055] Step 3: Add the aqueous phase material to the oil phase material at a mass ratio of 90:10, heat to 120℃ for emulsification and homogenization to obtain the emulsified matrix.
[0056] Step 4: Add hollow glass microspheres to the emulsion matrix at room temperature. The mass ratio of hollow glass microspheres to aqueous phase material is 1.6:90. Stir for 20 minutes to obtain emulsion explosive.
[0057] Example 9 The only difference from Example 1 is that the mass ratio of the aqueous phase material, the oil phase material, and the sensitizer is adjusted to 88:12:2.0.
[0058] The conditions and steps for preparing the polyisobutylene succinimide derivative are the same as in Example 1.
[0059] Preparation of high-temperature resistant downhole emulsion explosives: Step 1: Prepare the aqueous phase material according to the mass proportions. Mix 75 parts ammonium nitrate, 5 parts sodium nitrate, 6 parts urea, 0.4 parts chitosan quaternary ammonium salt and 14.6 parts water to obtain the aqueous phase material.
[0060] Step 2: Prepare the oil phase material according to the mass proportions. Add 20 parts of composite wax, 20 parts of microcrystalline wax and 20 parts of machine oil to a container, heat to 110℃, melt and stir until well mixed, add 20 parts of Span80 and 10 parts of polyisobutylene succinimide derivative, stir and mix until well mixed to obtain the oil phase material.
[0061] Step 3: Add the aqueous phase material to the oil phase material at a mass ratio of 88:12, heat to 120℃ for emulsification and homogenization to obtain the emulsified matrix.
[0062] Step 4: Add hollow glass microspheres to the emulsion matrix at room temperature. The mass ratio of hollow glass microspheres to aqueous phase material is 2.0:88. Stir for 20 minutes to obtain emulsion explosive.
[0063] Example 10 The only difference from Example 1 is that the mass ratio of the aqueous phase material, oil phase material and sensitizer is adjusted to 96:4:0.8.
[0064] The conditions and steps for preparing the polyisobutylene succinimide derivative are the same as in Example 1.
[0065] Preparation of high-temperature resistant downhole emulsion explosives: Step 1: Prepare the aqueous phase material according to the mass proportions. Mix 75 parts ammonium nitrate, 5 parts sodium nitrate, 6 parts urea, 0.4 parts chitosan quaternary ammonium salt and 14.6 parts water to obtain the aqueous phase material.
[0066] Step 2: Prepare the oil phase material according to the mass proportions. Add 20 parts of composite wax, 20 parts of microcrystalline wax and 20 parts of machine oil to a container, heat to 110℃, melt and stir until well mixed, add 20 parts of Span80 and 10 parts of polyisobutylene succinimide derivative, stir and mix until well mixed to obtain the oil phase material.
[0067] Step 3: Add the aqueous phase material to the oil phase material at a mass ratio of 96:4, heat to 120℃ for emulsification and homogenization to obtain the emulsified matrix.
[0068] Step 4: Add hollow glass microspheres to the emulsion matrix at room temperature. The mass ratio of hollow glass microspheres to aqueous phase material is 0.8:96. Stir for 20 minutes to obtain emulsion explosive.
[0069] Comparative Example 1 The only difference from Example 1 is that urea is not added to the aqueous phase material of the emulsion explosive.
[0070] The conditions and steps for preparing the polyisobutylene succinimide derivative are the same as in Example 1.
[0071] Preparation of high-temperature resistant downhole emulsion explosives: Step 1: Prepare the aqueous phase material according to the mass proportions. Mix 75 parts ammonium nitrate, 5 parts sodium nitrate, 0.4 parts chitosan quaternary ammonium salt with 14.6 parts water to obtain the aqueous phase material.
[0072] Step 2: Prepare the oil phase material according to the mass proportions. Add 20 parts of composite wax, 20 parts of microcrystalline wax and 20 parts of machine oil to a container, heat to 110℃, melt and stir until well mixed, add 20 parts of Span80 and 10 parts of polyisobutylene succinimide derivative, stir and mix until well mixed to obtain the oil phase material.
[0073] Step 3: Add the aqueous phase material to the oil phase material at a mass ratio of 90:10, heat to 120℃ for emulsification and homogenization to obtain the emulsified matrix.
[0074] Step 4: Add hollow glass microspheres to the emulsion matrix at room temperature. The mass ratio of hollow glass microspheres to aqueous phase material is 1.6:90. Stir for 20 minutes to obtain emulsion explosive.
[0075] Comparative Example 2 The only difference from Example 1 is that chitosan quaternary ammonium salt is not added to the aqueous phase material of the emulsion explosive.
[0076] The conditions and steps for preparing the polyisobutylene succinimide derivative are the same as in Example 1.
[0077] Preparation of high-temperature resistant downhole emulsion explosives: Step 1: Prepare the aqueous phase material according to the mass proportions. Mix 75 parts ammonium nitrate, 5 parts sodium nitrate, 6 parts urea and 14.6 parts water to obtain the aqueous phase material.
[0078] Step 2: Prepare the oil phase material according to the mass proportions. Add 20 parts of composite wax, 20 parts of microcrystalline wax and 20 parts of machine oil to a container, heat to 110℃, melt and stir until well mixed, add 20 parts of Span80 and 10 parts of polyisobutylene succinimide derivative, stir and mix until well mixed to obtain the oil phase material.
[0079] Step 3: Add the aqueous phase material to the oil phase material at a mass ratio of 90:10, heat to 120℃ for emulsification and homogenization to obtain the emulsified matrix.
[0080] Step 4: Add hollow glass microspheres to the emulsion matrix at room temperature. The mass ratio of hollow glass microspheres to aqueous phase material is 1.6:90. Stir for 20 minutes to obtain emulsion explosive.
[0081] Comparative Example 3 The only difference from Example 1 is that the polyisobutylene succinimide derivative is replaced with an equal mass of Span80 in the oil phase material of the emulsion explosive.
[0082] Preparation of high-temperature resistant downhole emulsion explosives: Step 1: Prepare the aqueous phase material according to the mass proportions. Mix 75 parts ammonium nitrate, 5 parts sodium nitrate, 6 parts urea, 0.4 parts chitosan quaternary ammonium salt and 14.6 parts water to obtain the aqueous phase material.
[0083] Step 2: Prepare the oil phase material according to the mass proportions. Add 20 parts of composite wax, 20 parts of microcrystalline wax and 20 parts of machine oil to a container, heat to 110℃, melt and stir until well mixed, add 30 parts of Span80, stir and mix until well mixed to obtain the oil phase material.
[0084] Step 3: Add the aqueous phase material to the oil phase material at a mass ratio of 90:10, heat to 120℃ for emulsification and homogenization to obtain the emulsified matrix.
[0085] Step 4: Add hollow glass microspheres to the emulsion matrix at room temperature. The mass ratio of hollow glass microspheres to aqueous phase material is 1.6:90. Stir for 20 minutes to obtain emulsion explosive.
[0086] The performance of the emulsion explosives prepared in Examples 1-10 and Comparative Examples 1-3 was tested, and the results are shown in Table 1.
[0087] The intensity and detonation velocity of the emulsion explosives in the examples and comparative examples were tested in accordance with the standard GB18095-2000 "Emulsion Explosives".
[0088] High temperature resistance: The emulsion explosives of the examples and comparative examples were stored at 90°C for 24 hours, and then the saturation and detonation velocity were tested.
[0089] Table 1
[0090] As shown in Table 1, the emulsion explosives prepared in the embodiments of the present invention possess beneficial high-temperature resistance. Their explosive performance does not significantly decrease after high-temperature treatment, and their performance remains stable. The results of Examples 1, 1 (Comparative Example), and 2 (Comparative Example) indicate that urea can promote the stabilization of the aqueous phase by chitosan quaternary ammonium salt, ensuring the performance stability of the emulsion explosive at high temperatures. Examples 6-8 added stabilizers to the emulsion based on Example 1. The test results show that the stabilizers can weaken the impact of high temperatures on the emulsion explosive. Combined with the results of Examples 1 and 3 (Comparative Example), adding polyisobutylene succinimide derivatives to the emulsifier can improve the high-temperature resistance of the emulsion, reduce the probability of demulsification, and ensure that the emulsion explosive maintains high detonation velocity and intensity after high-temperature treatment.
[0091] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.
[0092] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.
Claims
1. A high temperature resistant downhole emulsion explosive, characterized in that, It includes aqueous phase materials, oil phase materials, and sensitizers in a mass ratio of (88-96):(4-12):(0.8-2.0); The aqueous phase material, by mass parts, includes the following raw materials: Ammonium nitrate 70-80 parts, sodium nitrate 4-6 parts, urea 5-8 parts, chitosan quaternary ammonium salt 0.1-0.6 parts, water 10-20 parts; The oil phase material, by mass parts, includes the following raw materials: 50-70 parts of composite oil phase and 20-40 parts of composite emulsifier; The composite emulsifier includes Span80 and polyisobutylene succinimide derivatives; The structural formula of the polyisobutylene succinimide derivative is as follows: wherein R1is or .
2. The high temperature resistant downhole emulsion explosive of claim 1, wherein, The composite oil phase includes composite wax, microcrystalline wax and engine oil, with a mass ratio of (10-20):(15-25):(10-20).
3. The high temperature resistant downhole emulsion explosive of claim 1, wherein, The mass ratio of Span80 to polyisobutylene succinimide derivative in the composite emulsifier is 1:(0.4-0.7).
4. The high temperature resistant downhole emulsion explosive of claim 1, wherein, The preparation steps of the polyisobutylene succinimide derivative are as follows: A1. Add polyisobutylene succinic anhydride to the flask, install a reflux separator on the flask, add n-octane as a solvent, and stir until completely dissolved. A2. Heat the system to 60-80℃, add 2,2'-((2-aminoethyl)azadiyl)bis(ethanol-1-ol), heat to 95-100℃, stir the reaction for 8-10 hours, remove the solvent by rotary evaporation after the reaction is completed, and dry under vacuum to obtain the intermediate product. A3. Add the intermediate product and xylene to the flask, which is equipped with a reflux separator. Stir to dissolve and then heat to 80-90℃. A4. While stirring, add glucohepatic lactone to the system in step A3. After the addition is complete, heat to 110-120℃ and continue stirring to react. Take a sample during the reaction to determine the acid value. Stop the reaction when the acid value remains unchanged. A5. Extract the product of step A4 with saturated brine to remove unreacted substances, and then remove the solvent by rotary evaporation of the organic phase to obtain the product.
5. The high-temperature resistant downhole emulsion explosive according to claim 4, characterized in that, The polyisobutylene succinic anhydride is prepared from highly active polyisobutylene with a molecular weight of 1000 and has an acid value ≥70mgKOH / g.
6. The high-temperature resistant downhole emulsion explosive according to claim 4, characterized in that, The molar ratio of the polyisobutylene succinic anhydride and 2,2'-((2-aminoethyl)azadiyl)bis(ethanol-1-ol) is 3.00:1.05-1.
10.
7. The high-temperature resistant downhole emulsion explosive according to claim 4, characterized in that, The mass ratio of the intermediate product to glucoheponic acid lactone is 1:(0.12-0.13).
8. The high-temperature resistant downhole emulsion explosive according to claim 1, characterized in that, The oil phase material also includes a stabilizer, with the stabilizer having a mass fraction of 0.2-1.2 parts.
9. A high-temperature resistant downhole emulsion explosive according to claim 8, characterized in that, The stabilizer is one of 11-mercaptoundecylphosphonic acid and 12-mercaptododecylphosphonic acid.
10. A method for preparing a high-temperature resistant downhole emulsion explosive, characterized in that, The preparation of the high-temperature resistant downhole emulsion explosive as described in any one of claims 1-9 includes the following steps: Step 1: Mix ammonium nitrate, sodium nitrate, urea, chitosan quaternary ammonium salt with water to obtain an aqueous phase material; Step 2: Heat the composite oil phase to 100-110℃, mix it well, add the other raw materials in the oil phase, stir and mix well to obtain the oil phase material; Step 3: Add the aqueous phase material to the oil phase material according to the mass ratio, heat to 100-130℃ for emulsification and homogenization to obtain the emulsified matrix; Step 4: Add the sensitizer to the emulsion matrix at room temperature and stir to obtain the emulsion explosive.