Improved liquid-mixed expanded ammonium nitrate explosive and preparation method thereof

Abstract

The application discloses an improved liquid-mixed expanded ammonium nitrate explosive and a preparation method thereof. The expanded ammonium nitrate explosive is composed of the following components in percentage by mass: 90-94% of ammonium nitrate, 3-5% of wood powder, 3-5% of integrated composite oil phase, and further including mica powder and polypropylene glycol as additives, wherein the adding amount of the mica powder is 5-20% of the total mass, and the adding amount of the polypropylene glycol is 2-5% of the total mass. The preparation method comprises the following steps: (1) preparing an ammonium nitrate aqueous solution; (2) heating and melting the integrated oil phase; (3) expanding and crystallizing; (4) adding the expanded ammonium oil mixture, the wood powder, the mica powder and the polypropylene glycol into a medicine mixer to be uniformly rolled, mixed and cooled. The mica powder is used in the expanded ammonium nitrate explosive to improve the bulk density and the charge density of the expanded explosive, and the polypropylene glycol is introduced to prevent the segregation phenomenon of the mica powder and the base explosive, so that the stability of the product performance is ensured.

Description

Technical Field

[0001] This invention relates to an ammonium nitrate explosive machine and its preparation method, and particularly to an improved liquid-mixed expanded ammonium nitrate explosive and its preparation method. Background Technology

[0002] The production process of expanded ammonium nitrate explosives employs liquid-mixing technology, which improves mixing uniformity, results in excellent explosive performance, and ensures stable and reliable quality. However, with the widespread application of expanded ammonium nitrate explosives, defects such as poor flowability, low charge density, and susceptibility to clumping in humid environments have emerged. Currently, research on improving the performance of liquid-mixed expanded ammonium nitrate explosives commonly involves adding appropriate amounts of porous granular ammonium nitrate or heavy calcium carbonate to adjust its physical and explosive properties, thus improving its performance to some extent. However, due to the density difference between porous granular ammonium nitrate or heavy calcium carbonate and the base explosive, mixing uniformity is affected, and segregation is prone to occur. Therefore, other functional additives are needed to further improve the performance of liquid-mixed expanded ammonium nitrate explosives. Summary of the Invention

[0003] Objectives of the Invention: The first objective of this invention is to provide an improved liquid-mixed expanded ammonium nitrate explosive, which increases the bulk density and charge density of the expanded explosive, while preventing the segregation of additives and matrix explosives, thereby improving product stability; the second objective of this invention is to provide a method for preparing the improved liquid-mixed expanded ammonium nitrate explosive.

[0004] Technical solution: The improved liquid-mixed expanded ammonium nitrate explosive of the present invention is composed of the following components by mass percentage: 90-94% ammonium nitrate, 3-5% wood flour, 3-5% integrated composite oil phase, and also includes external additives mica powder and polypropylene glycol, wherein the amount of mica powder added is 5-20% of the total mass and the amount of polypropylene glycol added is 2-5% of the total mass.

[0005] The mica powder and polypropylene glycol are added additives. The mica powder, as a functional additive, has a true density of 2.77 g / cm³. 3 Its high density and chemical stability can be used to increase the bulk density and charge density of expanded explosives. The clear, transparent, viscous liquid nature and non-volatile properties of polypropylene glycol can, to some extent, prevent the segregation of mica powder from the matrix explosive, ensuring stable product performance.

[0006] Preferably, the mica powder has a particle size of 60-125 mesh.

[0007] Preferably, the molecular weight of the polypropylene glycol is 400-1000.

[0008] Preferably, the integrated composite oil phase is a composite wax and octadecaneamine acetate, wherein the content of octadecaneamine acetate is 4-6%.

[0009] The preparation method of the improved liquid-mixed expanded ammonium nitrate explosive of the present invention includes the following steps:

[0010] (1) Aqueous phase preparation: Add water to the ammonium nitrate dissolving tank, crush the ammonium nitrate and put it into the dissolving tank to prepare an ammonium nitrate aqueous solution, stir and keep warm for later use;

[0011] (2) Oil phase preparation: Add the integrated oil phase to the oil phase melting tank, heat and melt it, stir and keep it warm for later use;

[0012] (3) Expansion crystallization: The aqueous phase and the oil phase are mixed evenly in a mixer and then sent to an expansion crystallizer for expansion and drying under vacuum to form a fluffy expanded ammonium oil mixture;

[0013] (4) Mixing drugs:

[0014] The expanded ammonium oil mixture, wood flour, mica powder and polypropylene glycol are added to a mixer, crushed and mixed evenly, and then cooled to obtain an improved liquid-mixed expanded ammonium nitrate explosive before loading.

[0015] Preferably, in step (1), the mass fraction of the ammonium nitrate aqueous solution is 90.9-92.5%.

[0016] Preferably, in step (1), the temperature of the ammonium nitrate aqueous solution is controlled at 125-128°C to prevent the ammonium nitrate aqueous solution from crystallizing.

[0017] Preferably, in step (2), the heating and melting temperature is 90-95℃.

[0018] Preferably, in step (4), the cooling temperature is 50-60°C.

[0019] Preferably, after step (4) is completed, the explosive is loaded, and the loading temperature of the expanded ammonium nitrate explosive is controlled at 45-50℃.

[0020] Beneficial effects: Compared with the prior art, the present invention has the following significant advantages: (1) The present invention improves the bulk density and charge density of the expanded ammonium nitrate explosive by using mica powder as a functional additive, and at the same time introduces polypropylene glycol to prevent the separation of mica powder from the base explosive and ensure the stability of product performance; (2) The preparation method is simple and easy to industrialize. Attached Figure Description

[0021] Figure 1 This is a photograph of the improved liquid-mixed expanded ammonium nitrate explosive prepared in Example 4. Detailed Implementation

[0022] The technical solution of the present invention will be further described below with reference to the embodiments.

[0023] Example 1

[0024] The improved liquid-mixed expanded ammonium nitrate explosive of this invention is composed of the following components by mass percentage: 92% ammonium nitrate, 4% wood flour (80 mesh), 4% integrated composite oil phase, and 5% mica powder (bulk density 0.35 g / cm³). 3 It contains 60 mesh particles and 2% polypropylene glycol (molecular weight 400).

[0025] Its preparation method includes the following steps:

[0026] (1) Aqueous phase preparation: Add 92 g of water to the ammonium nitrate dissolving tank, heat and stir, add 920 g of crushed ammonium nitrate to the dissolving tank, prepare a 90.9% ammonium nitrate aqueous solution, control the temperature of the solution at 125℃, stir and keep warm for later use.

[0027] (2) Oil phase preparation: Add 40 g of integrated oil phase to the oil phase melting tank, heat and melt at 90°C, stir and keep warm for later use. The integrated oil phase is a mixture of composite wax and octadecaneamine acetate, wherein the content of octadecaneamine acetate is 6%.

[0028] (3) Expansion crystallization: The aqueous phase and the oil phase are mixed evenly in a mixer and then sent to an expansion crystallizer for expansion and drying under vacuum. The vacuum degree is 0.093 MPa, forming a fluffy expanded ammonium oil mixture.

[0029] (4) Mixing drugs:

[0030] The expanded ammonium oil mixture, 40g of wood flour, 50g of mica powder and 20g of polypropylene glycol are added to a mixer, crushed and mixed evenly, and cooled (50-60℃) to obtain the improved liquid-mixed expanded ammonium nitrate explosive before loading.

[0031] (5) Loading explosives:

[0032] The temperature during the loading process is controlled at 45-50℃.

[0033] Example 2

[0034] The improved liquid-mixed expanded ammonium nitrate explosive of this invention is composed of the following components by mass percentage: 92% ammonium nitrate, 3% wood flour (80 mesh), 5% integrated composite oil phase, and 20% mica powder (bulk density 0.22 g / cm³). 3 It contains 125 mesh particles and 5% polypropylene glycol (molecular weight 1000).

[0035] Its preparation method includes the following steps:

[0036] (1) Aqueous phase preparation: Add 92 g of water to the ammonium nitrate dissolving tank, heat and stir, add 920 g of crushed ammonium nitrate to the dissolving tank, prepare a 90.9% ammonium nitrate aqueous solution, control the temperature of the solution at 125℃, stir and keep warm for later use;

[0037] (2) Oil phase preparation: Add 50 g of integrated oil phase to the oil phase melting tank, heat and melt at 95°C, stir and keep warm for later use; the integrated oil phase is a mixture of composite wax and octadecaneamine acetate, wherein the content of octadecaneamine acetate is 4%.

[0038] (3) Expansion crystallization: The aqueous phase and the oil phase are mixed evenly in a mixer and then sent to an expansion crystallizer for expansion and drying under vacuum. The vacuum degree is 0.093 MPa, forming a fluffy expanded ammonium oil mixture.

[0039] (4) Mixing drugs:

[0040] The expanded ammonium oil mixture, 30 g of wood flour, 200 g of mica powder and 50 g of polypropylene glycol were added to a mixer, crushed and mixed evenly, and cooled (50-60℃) to obtain the improved liquid-mixed expanded ammonium nitrate explosive.

[0041] (5) Loading explosives:

[0042] The loading temperature should be controlled at 45-50℃.

[0043] Example 3

[0044] The improved liquid-mixed expanded ammonium nitrate explosive of this invention is composed of the following components by mass percentage: 94% ammonium nitrate, 3% wood flour (80 mesh), 3% integrated composite oil phase, and 10% mica powder (bulk density 0.22 g / cm³). 3 It contains 125 mesh particles and 3% polypropylene glycol (molecular weight 1000).

[0045] Its preparation method includes the following steps:

[0046] (1) Aqueous phase preparation: Add 76 g of water to the ammonium nitrate dissolving tank, heat and stir, add 940 g of crushed ammonium nitrate to the dissolving tank, prepare a 92.5% ammonium nitrate aqueous solution, control the temperature of the solution at 128℃, stir and keep warm for later use.

[0047] (2) Oil phase preparation: Add 30 g of integrated oil phase to the oil phase melting tank, heat and melt at 90°C, stir and keep warm for later use. The integrated oil phase is a mixture of composite wax and octadecaneamine acetate, wherein the content of octadecaneamine acetate is 6%.

[0048] (3) Expansion crystallization: The aqueous phase and the oil phase are mixed evenly in a mixer and then sent to an expansion crystallizer for expansion and drying under vacuum. The vacuum degree is 0.093 MPa, forming a fluffy expanded ammonium oil mixture.

[0049] (4) Mixing drugs:

[0050] The expanded ammonium oil mixture, 30g wood flour, 100g mica powder and 30g polypropylene glycol are added to a mixer, crushed and mixed evenly, and cooled (50-60℃) to obtain the improved liquid-mixed expanded ammonium nitrate explosive before loading.

[0051] (5) Packaging of the drug:

[0052] After continuous cooling, mixing, and conveying, the finished powdered medicine is fed into the hopper of a fully automatic bagging machine to be filled into bags, with the filling temperature controlled at 45-50℃.

[0053] Example 4

[0054] The improved liquid-mixed expanded ammonium nitrate explosive of this invention is composed of the following components by mass percentage: 92% ammonium nitrate, 5% wood flour (80 mesh), 3% integrated composite oil phase, and 15% mica powder (bulk density 0.35 g / cm³). 3 It contains 60 mesh particles and 4% polypropylene glycol (molecular weight 400).

[0055] (1) Aqueous phase preparation: Add 92 g of water to the ammonium nitrate dissolving tank, heat and stir, add 920 g of crushed ammonium nitrate to the dissolving tank, prepare a 90.9% ammonium nitrate aqueous solution, control the temperature of the solution at 125℃, stir and keep warm for later use.

[0056] (2) Oil phase preparation: Add 30 g of integrated oil phase to the oil phase melting tank, heat and melt at 90°C, stir and keep warm for later use. The integrated oil phase is a mixture of composite wax and octadecaneamine acetate, wherein the content of octadecaneamine acetate is 6%.

[0057] (3) Expansion crystallization: The aqueous phase and the oil phase are mixed evenly in a mixer and then sent to an expansion crystallizer for expansion and drying under vacuum. The vacuum degree is 0.093 MPa, forming a fluffy expanded ammonium oil mixture.

[0058] (4) Mixing drugs:

[0059] The expanded ammonium oil mixture, 50 g of wood flour, 150 g of mica powder and 40 g of polypropylene glycol were added to a mixer, crushed and mixed evenly, and cooled (50-60℃) to obtain the improved liquid-mixed expanded ammonium nitrate explosive.

[0060] (5) Loading explosives:

[0061] The loading temperature should be controlled at 45-50℃.

[0062] Example 5

[0063] The improved liquid-mixed expanded ammonium nitrate explosive of this invention is composed of the following components by mass percentage: 90% ammonium nitrate, 5% wood flour (80 mesh), 5% integrated composite oil phase, and 15% mica powder (bulk density 0.35 g / cm³). 3 It contains 60 mesh particles and 4% polypropylene glycol (molecular weight 400).

[0064] (1) Aqueous phase preparation: Add 84 g of water to the ammonium nitrate dissolving tank, heat and stir, add 900 g of crushed ammonium nitrate to the dissolving tank, prepare a 91.5% ammonium nitrate aqueous solution, control the temperature of the solution at 125℃, stir and keep warm for later use.

[0065] (2) Oil phase preparation: Add 50 g of integrated oil phase to the oil phase melting tank, heat and melt at 90°C, stir and keep warm for later use. The integrated oil phase is a mixture of composite wax and octadecaneamine acetate, wherein the content of octadecaneamine acetate is 6%.

[0066] (3) Expansion crystallization: The aqueous phase and the oil phase are mixed evenly in a mixer and then sent to an expansion crystallizer for expansion and drying under vacuum. The vacuum degree is 0.093 MPa, forming a fluffy expanded ammonium oil mixture.

[0067] (4) Mixing drugs:

[0068] The expanded ammonium oil mixture, 50 g of wood flour, 150 g of mica powder and 40 g of polypropylene glycol were added to a mixer, crushed and mixed evenly, and cooled (50-60℃) to obtain the improved liquid-mixed expanded ammonium nitrate explosive.

[0069] (5) Loading explosives:

[0070] The loading temperature should be controlled at 45-50℃.

[0071] Comparative Example 1

[0072] Based on Example 1, only 5% mica powder was added as a functional additive, while the other conditions remained unchanged, to obtain expanded ammonium nitrate explosive.

[0073] Comparative Example 2

[0074] Based on Example 1, the functional additive only contains 5% heavy calcium carbonate (bulk density 1.29 g / cm³). 3 With the particle size of 70 mesh unchanged, expanded ammonium nitrate explosive was obtained.

[0075] The performance of ammonium nitrate explosives in Examples 1-4 and Comparative Examples 1-2 was tested, and the test results are shown in Table 1.

[0076] Table 1 Performance test data of ammonium nitrate explosive

[0077] sample <![CDATA[Bulk density (g / cm 3 )]]> Average explosion velocity (m / s) Psycho detonation distance (cm) Example 1 0.41 3483 7 Example 2 0.35 3147 5 Example 3 0.36 3372 5 Example 4 0.38 3281 5 Example 5 0.37 3146 5 Comparative Example 1 0.39 3382 5 Comparative Example 2 0.45 3305 5

[0078] As shown in Table 1, the expanded ammonium nitrate explosives prepared by mica powder and polypropylene glycol in Examples 1-5 have excellent explosive performance. However, the explosive performance decreases with the increase of mica powder content. This is because mica powder is an insensitive substance and does not participate in the detonation reaction. Moreover, the finer mica powder plays a role in coating and insensitizing.

[0079] Comparative Example 1 only added mica powder as an additive. Compared with Example 1, its performance decreased because polypropylene glycol was not added, which caused segregation and a decrease in explosive performance.

[0080] Compared to Example 1, Comparative Example 2 showed a decrease in performance when the same mass of calcium carbonate was added. This is because, without the addition of polypropylene glycol, the bulk density of heavy calcium carbonate is greater than that of mica powder, making it more prone to segregation and resulting in a decrease in explosive performance.

[0081] From the appendix Figure 1 It can be seen that the improved liquid-mixed expanded ammonium nitrate explosive prepared in Example 4 is a powdery mixture with uniform particles. Although the content of 60-mesh mica powder with a larger particle size reaches 15%, no obvious segregation phenomenon occurs under the action of viscous liquid polypropylene glycol.

Claims

1. An improved liquid-mixed expanded ammonium nitrate explosive, characterized in that, By mass percentage, it consists of the following components: 90-94% ammonium nitrate, 3-5% wood flour, 3-5% integrated composite oil phase, and also includes external additives mica powder and polypropylene glycol, wherein the amount of mica powder added is 5-20% of the total mass and the amount of polypropylene glycol added is 2-5% of the total mass.

2. The improved liquid-mixed expanded ammonium nitrate explosive according to claim 1, characterized in that, The mica powder has a particle size of 60-125 mesh.

3. The improved liquid-mixed expanded ammonium nitrate explosive according to claim 1, characterized in that, The molecular weight of the polypropylene glycol is 400-1000.

4. The improved liquid-mixed expanded ammonium nitrate explosive according to claim 1, characterized in that, The integrated composite oil phase consists of composite wax and octadecaneamine acetate, wherein the content of octadecaneamine acetate is 4-6%.

5. A method for preparing the improved liquid-mixed expanded ammonium nitrate explosive according to any one of claims 1 to 4, characterized in that, Includes the following steps: (1) Aqueous phase preparation: Add water to the ammonium nitrate dissolving tank, crush the ammonium nitrate and put it into the dissolving tank to prepare an ammonium nitrate aqueous solution, stir and keep warm for later use; (2) Oil phase preparation: Add the integrated oil phase to the oil phase melting tank, heat and melt it, stir and keep it warm for later use; (3) Expansion crystallization: The aqueous phase and the oil phase are mixed evenly in a mixer and then sent to an expansion crystallizer for expansion and drying under vacuum to form a fluffy expanded ammonium oil mixture; (4) Mixing drugs: The expanded ammonium oil mixture, wood flour, mica powder and polypropylene glycol are added to a mixer, crushed and mixed evenly, and then cooled to obtain an improved liquid-mixed expanded ammonium nitrate explosive before loading.

6. The method for preparing the improved liquid-mixed expanded ammonium nitrate explosive according to claim 5, characterized in that, In step (1), the mass fraction of the ammonium nitrate aqueous solution is 90.9-92.5%.

7. The method for preparing the improved liquid-mixed expanded ammonium nitrate explosive according to claim 5, characterized in that, In step (1), the temperature of the ammonium nitrate aqueous solution is controlled at 125-128℃.

8. The method for preparing the improved liquid-mixed expanded ammonium nitrate explosive according to claim 5, characterized in that, In step (2), the heating and melting temperature is 90-95℃.

9. The preparation method of the improved liquid-mixed expanded ammonium nitrate explosive according to claim 5, characterized in that, In step (4), the cooling temperature is 50-60℃.

10. The method for preparing the improved liquid-mixed expanded ammonium nitrate explosive according to claim 5, characterized in that, After step (4) is completed, the explosive is loaded, and the loading temperature of the expanded ammonium nitrate explosive is controlled at 45-50℃.

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