Oxygen candle ignition powder and preparation method thereof

Abstract

The oxygen candle ignition powder is prepared from the following components in percentage by mass: 20%-46% of oxidant powder, 15%-32% of fuel powder and 28%-56% of inert inorganic filler, the fuel powder is composed of main fuel powder and auxiliary fuel powder according to the weight ratio of (1-8): 1. The preparation method comprises the following steps: uniformly mixing the raw materials in a dry manner, and loading into a mold press for compression molding. The oxygen candle ignition powder is suitable for rapidly igniting the oxygen production grain to generate oxygen when the solid chemical oxygen generator is fired and ignited, and the oxygen candle ignition powder is low in mechanical sensitivity and high in use safety; the formability is good, and the impact vibration resistance effect of the grain is strong; the ignition performance is good, and ignition and fire transfer in the environment of-40 DEG C to 70 DEG C can be achieved; the preparation method is simple, and the modular production efficiency is high.

Description

Technical Field

[0001] The present invention belongs to the field of manufacturing compositions of explosives or thermites, and particularly relates to an ignition charge for an oxygen candle. Background Art

[0002] An oxygen candle (solid chemical oxygen generator) is an oxygen supply device that uses a chemical reaction to generate oxygen, and is widely used in enclosed spaces such as aerospace, aviation, navigation, and mines. It is an important device for hypoxia protection and emergency escape. An oxygen candle mainly consists of an ignition system, an oxygen generation system, a heat insulation system, and a filtration system. The ignition system includes an igniter and an ignition charge. The ignition charge is located at the head of the oxygen generation charge column and is excited by the energy released by an electric igniter or an impact primer. It uses a large amount of high-temperature gas or glowing solid particles generated during combustion to provide sufficient energy and temperature to ignite the oxygen generation charge column, playing a role of relay ignition. The ignition charge plays a crucial role in the working performance of the oxygen candle, affecting the quality reliability and mission safety of the oxygen candle under various environmental conditions.

[0003] At present, relatively in-depth research has been carried out on the ignition charges for oxygen candles, and basically the fire transfer target can be achieved. However, most of the current domestic ignition charges for oxygen candles have problems such as unstable low-temperature ignition performance, high sensitivity, high safety risks, poor formability, and low production efficiency due to immature processes.

[0004] For example, the ignition charges disclosed in Chinese patents CN1817824A and CN103204755A both use the method of applying or pressing a layer of titanium powder on the surface of the ignition charge, indicating that the ignition ability of the ignition charge in the patent is poor, and there are disadvantages such as easy shedding of titanium powder and poor process consistency. At the same time, the ignition charge in the patent needs to be formed relying on the groove of the oxygen generation charge column, indicating that the formability of the ignition charge is poor and it cannot be formed alone.

[0005] Chinese patents CN108083235A, CN114890853A, and CN114804987A use barium chromate as an oxidant and magnesium powder, zirconium powder, etc. as fuels, and have disadvantages such as high formulation sensitivity, poor safety, insufficient calorific value, and poor low-temperature ignition performance. At the same time, processes such as chemical precipitation method and acid-base intervention are complex and the production efficiency is low.

[0006] Chinese patent CN107619021A wet-mixes the oxygen candle ignition charge and the oxygen generation charge column with water respectively, and then places the ignition charge on the oxygen generation charge column and presses them together. Wet pressing requires uniform wet mixing before pressing and high-temperature drying after pressing. These steps increase the process cost and extend the product production cycle. Pressing and demolding the ignition charge and the oxygen generation charge column together are prone to deflagration and explosion, and the safety is not good. Moreover, a large amount of ignition powder is required to ensure integral forming. Summary of the Invention

[0007] The object of the present invention is to overcome the above deficiencies of the prior art and provide an oxygen candle ignition charge, which has low mechanical sensitivity, high use safety, good formability, strong anti-impact and anti-vibration effects of the drug column, and good low-temperature ignition performance.

[0008] The technical solution provided by the present invention is as follows: An oxygen candle ignition charge, which is suitable for quickly igniting an oxygen-producing drug column to generate oxygen when a solid chemical oxygen generator is struck and ignited, and is composed of the following components in mass percentage: 20%-46% of oxidant powder, 15%-32% of fuel powder, and 28%-56% of inert inorganic filler;

[0009] The fuel powder is composed of a main fuel powder and an auxiliary fuel powder with a weight ratio of (1-8):1.

[0010] The oxidant powder is selected from one or more of sodium chlorate, sodium perchlorate, potassium chlorate, and potassium perchlorate.

[0011] The main fuel powder is selected from one or more of Mg, Al, and Ti powders.

[0012] The auxiliary fuel powder is selected from one or more of Si, Fe, Sn, and Mn powders.

[0013] The inert inorganic filler is selected from one or more of metal oxides, silicon dioxide, sulfate compounds, silicate compounds, and boron nitride.

[0014] Preferably, the inert inorganic filler is selected from one or more of zinc oxide, nickel oxide, titanium oxide, chromium oxide, aluminum oxide, silicon dioxide, magnesium sulfate, calcium sulfate, calcium silicate, and boron nitride.

[0015] The particle size of the oxidant powder is 60-200 mesh; the particle size of the fuel powder is 100-400 mesh; the particle size of the inert inorganic filler is not less than 800 mesh.

[0016] On the other hand, the present invention also provides an oxygen candle ignition charge block, which is formed by dry-mixing 20%-46% of oxidant powder, 15%-32% of fuel powder, and 28%-56% of inert inorganic filler in mass percentage and then pressing them into shape;

[0017] The fuel powder is composed of a main fuel powder and an auxiliary fuel powder with a weight ratio of (1-8):1.

[0018] The oxidant powder is selected from one or more of sodium chlorate, sodium perchlorate, potassium chlorate, and potassium perchlorate, and the particle size is 60-200 mesh.

[0019] The main fuel powder is selected from one or more of Mg, Al, and Ti powders, and the particle size is 100-400 mesh. The auxiliary fuel powder is selected from one or more of Si, Fe, Sn, and Mn powders, and the particle size is 100-400 mesh.

[0020] The inert inorganic filler is selected from one or more of metal oxides, silica, sulfate compounds, silicate compounds, and boron nitride, and the mesh number of the particle size is not less than 800.

[0021] On the other hand, the present invention also provides a preparation method of an oxygen candle ignition agent, comprising the following steps:

[0022] S1. Weigh 20%-46% of oxidant powder, 15%-32% of fuel powder, and 28%-56% of inert inorganic filler by mass percentage in proportion, and mix and sieve to disperse the powders; the fuel powder is composed of main fuel powder and auxiliary fuel powder with a weight ratio of (1-8):1;

[0023] S2. Pour the sieved mixture into a mixer, mix it, and pour it out after making it uniform to complete the dry mixing of the ignition agent;

[0024] S3. Load the ignition agent after dry mixing into a mold and press it into shape.

[0025] In step S1, the oxidant powder is selected from one or more of sodium chlorate, sodium perchlorate, potassium chlorate, and potassium perchlorate, and the particle size is 60-200 mesh.

[0026] The main fuel powder is selected from one or more of Mg, Al, and Ti powders, and the particle size is 100-400 mesh. The auxiliary fuel powder is selected from one or more of Si, Fe, Sn, and Mn powders, and the particle size is 100-400 mesh.

[0027] The inert inorganic filler is selected from one or more of metal oxides, silica, sulfate compounds, silicate compounds, and boron nitride, and the mesh number of the particle size is not less than 800.

[0028] In step S2, the mixing time is 5-10 min.

[0029] In step S3, an automatic press is used for pressing, the press pressure is 30-50 T / cm 2 , and the density of the ignition agent column after pressing into shape is 1.7-2.3 g / cm 3 .

[0030] Compared with the prior art, the advantages of the present invention are as follows:

[0031] 1) The ignition charge has low mechanical sensitivity and high safety. The inert inorganic filler can perform a desensitization treatment on the ignition charge, forming a well-performing protective layer between the oxidizer and the fuel, which can prevent and extinguish the explosive propagation of hot spots under mechanical action, play a heat-absorbing filling role and a friction buffering role between the oxidizer and metal particles, thereby reducing its sensitivity under mechanical action and improving the safety during transportation and use. At the same time, the inorganic filler is beneficial to the formation of the grain without cracking and the stable residue without flowing, improves the ignition performance, and further enhances the ignition safety.

[0032] 2) The preparation method is simple and the modular production efficiency is high. The wet mixing and drying processes are not required during the forming process, and the dry powder is directly pressed, significantly improving the production efficiency. At the same time, the ignition charge is separately formed in a modular manner, and the pressing and demolding processes are not affected or restricted by the oxygen-producing grain, with good process consistency.

[0033] 3) The ignition charge has good formability, can be pressed into various grain shapes according to the grain design, has a high density, and a strong anti-impact and anti-vibration effect.

[0034] 4) The ignition charge has good ignition performance. The particle size of the inorganic filler is significantly smaller than that of the oxidizer and fuel powders, so it does not affect the ignition and combustion performance of the ignition charge, and can achieve ignition and flame transfer in the environment of -40°C to 70°C.

[0035] 5) The ignition charge has a low gas generation rate, which is beneficial to the qualification of the gas component index of the oxygen candle product; there is no catalyst in the formula and the decomposition temperature is relatively high, so the calorific value is high, which is beneficial to the flame transfer performance of the ignition charge at low temperatures. Specific Embodiments

[0036] To facilitate the understanding of the present invention, the following will describe the present invention more comprehensively and meticulously in combination with preferred embodiments, but the protection scope of the present invention is not limited to the following specific embodiments.

[0037] Unless otherwise defined, all the professional terms used hereinafter have the same meaning as commonly understood by those skilled in the art. The professional terms used herein are only for the purpose of describing specific embodiments and are not intended to limit the protection scope of the present invention.

[0038] Unless otherwise specifically stated, all kinds of raw materials, reagents, instruments, and equipment used in the present invention can be obtained through market purchase or can be prepared by existing methods.

[0039] Example 1

[0040] The particle size and proportion of the components of the oxygen candle ignition charge in this example are shown in Table 1.

[0041] Table 1

[0042]

[0043] The preparation method of the oxygen candle ignition charge in this embodiment is as follows:

[0044] Weigh 28 g of potassium perchlorate with 80 mesh, 12 g of aluminum powder with 300 mesh, 12 g of tin powder with 400 mesh, 32 g of zinc oxide with 3000 mesh, and 16 g of calcium silicate with 7000 mesh. Sieve them through an 80-mesh sieve to disperse the powder. Pour the sieved mixture into a mixer and mix it with a vortex mixer for 5 minutes. After making it uniform, pour it out to complete the dry mixing of the ignition charge;

[0045] Weigh 15 g of the dry-mixed and uniform ignition charge and put it into a mold, and use an automatic press to press it into shape. The pressure of the press is 30 T / cm 2 After pressing into shape, the density of the ignition charge column is 1.9 g / cm 3 .

[0046] For the ignition charge produced in this embodiment, the impact sensitivity is 0%, the friction sensitivity is 8%, the electrostatic sensitivity is 3876 V, the flame sensitivity is 75 / 90 mm, the explosion heat is 5.4 kJ / g. After a 6-hour durability vibration test at 0.03 g 2 / Hz, the shedding and powder loss rate is ≤0.6%. Install it in an oxygen generator with a primer device and keep it at -40°C, 23°C, and 70°C for 4 hours respectively, then ignite it. The ignition is successful and the oxygen-producing charge column burns continuously.

[0047] Example 2

[0048] The particle size and proportion of the components in the oxygen candle ignition charge formula of this embodiment are shown in Table 2.

[0049] Table 2

[0050]

[0051] The preparation method of the oxygen candle ignition charge in this embodiment is as follows:

[0052] Weigh 32 g of sodium chlorate with 200 mesh, 12 g of magnesium powder with 300 mesh, 5 g of silicon powder with 400 mesh, 30 g of nickel oxide with 4000 mesh, and 21 g of magnesium sulfate with 900 mesh. Sieve them through a 200-mesh sieve to disperse the powder. Pour the sieved mixture into a mixer and mix it with a vortex mixer for 5 minutes. After making it uniform, pour it out to complete the dry mixing of the ignition charge;

[0053] Weigh 15 g of the dry-mixed and uniform ignition charge and put it into a mold, and use an automatic press to press it into shape. The pressure of the press is 30 T / cm 2 After pressing into shape, the density of the ignition charge column is 1.8 g / cm 3 .

[0054] For the ignition charge produced in this embodiment, the impact sensitivity is 0%, the friction sensitivity is 0%, the electrostatic sensitivity is 3318 V, the flame sensitivity is 45 / 90 mm, the explosion heat is 4.8 kJ / g. After a 6-hour durability vibration test at 0.03 g 2The powder shedding rate after 6-hour durability vibration test at / Hz is ≤0.8%. It is installed in an oxygen generator with a primer device and is heated at -40°C, 23°C, and 70°C for 4 hours respectively and then ignited. The ignition is successful and the oxygen-producing medicine column burns continuously.

[0055] Example 3

[0056] The particle size and proportion of the components of the oxygen candle ignition medicine in this example are shown in Table 3.

[0057] Table 3

[0058]

[0059] The preparation method of the oxygen candle ignition medicine in this example is as follows:

[0060] Weigh 20 g of sodium chlorate with 200 mesh, 22 g of sodium perchlorate with 60 mesh, 18 g of magnesium powder with 300 mesh, 4 g of iron powder with 400 mesh, 28 g of silicon dioxide with 2000 mesh, and 8 g of titanium oxide with 1200 mesh. Sieve them through a 60-mesh sieve to disperse the powder. Pour the mixture under the sieve into a mixer and mix it with a vortex mixer for 5 minutes. After making it uniform, pour it out to complete the dry mixing of the ignition medicine.

[0061] Weigh 20 g of the dry-mixed and uniform ignition medicine and put it into a mold, and use an automatic press to press it into shape. The pressure of the press is 40 T / cm 2 , and the density of the ignition medicine column after pressing is 2.1 g / cm 3 .

[0062] For the ignition medicine produced in this example, the impact sensitivity is 0%, the friction sensitivity is 4%, the electrostatic sensitivity is 2983 V, the flame sensitivity is 65 / 90 mm, the heat of explosion is 5.2 kJ / g. After the 6-hour durability vibration test at 0.03 g / Hz, the powder shedding rate is ≤0.4%. It is installed in an oxygen generator with a primer device and is heated at -40°C, 23°C, and 70°C for 4 hours respectively and then ignited. The ignition is successful and the oxygen-producing medicine column burns continuously. 2 For the ignition medicine produced in this example, the impact sensitivity is 0%, the friction sensitivity is 4%, the electrostatic sensitivity is 2983 V, the flame sensitivity is 65 / 90 mm, the heat of explosion is 5.2 kJ / g. After the 6-hour durability vibration test at 0.03 g / Hz, the powder shedding rate is ≤0.4%. It is installed in an oxygen generator with a primer device and is heated at -40°C, 23°C, and 70°C for 4 hours respectively and then ignited. The ignition is successful and the oxygen-producing medicine column burns continuously.

[0063] Example 4

[0064] The particle size and proportion of the components of the oxygen candle ignition medicine in this example are shown in Table 4.

[0065] Table 4

[0066] Name Oxidizer Main fuel Auxiliary fuel Inert inorganic filler Sodium chlorate Titanium powder Tin powder Boron nitride Particle size 100 mesh 100 mesh 400 mesh 8000 mesh Ratio 36％ 14％ 7％ 43％

[0067] The preparation method of the oxygen candle ignition medicine in this example is as follows:

[0068] Weigh 36 g of 100-mesh sodium chlorate, 14 g of 100-mesh titanium powder, 7 g of 400-mesh tin powder, and 43 g of 8000-mesh boron nitride. Sieve them through a 100-mesh sieve to disperse the powder. Pour the sieved mixture into a mixer and mix it with a vortex mixer for 5 minutes. After it becomes uniform, pour it out to complete the dry mixing of the ignition charge.

[0069] Weigh 15 g of the uniformly dry-mixed ignition charge and put it into a mold. Use an automatic press to press it into shape. The pressure of the press is 40 T / cm 2 , and the density of the ignition charge column after pressing is 1.9 g / cm 3 .

[0070] For the ignition charge produced in this example, the impact sensitivity is 0%, the friction sensitivity is 0%, the electrostatic sensitivity is 3523 V, the flame sensitivity is 50 / 90 mm, the heat of explosion is 5.1 kJ / g. After a 6-hour durability vibration test at 0.03 g 2 / Hz, the powder shedding rate is ≤0.2%. Install it in an oxygen generator with a primer device and keep it at -40°C, 23°C, and 70°C for 4 hours respectively, then ignite it. The ignition is successful and the oxygen-producing charge column burns continuously.

Claims

1. An oxygen candle ignition agent, characterized in that: It consists of the following components by mass percentage: 20%-46% of oxidizer powder, 15%-32% of fuel powder, and 28%-56% of inert inorganic filler; The fuel powder is composed of main fuel powder and auxiliary fuel powder with a weight ratio of (1-8):

1.

2. The oxygen candle ignition agent according to claim 1, wherein: The oxidizer powder is selected from one or more of sodium chlorate, sodium perchlorate, potassium chlorate, and potassium perchlorate; The main fuel powder is selected from one or more of Mg, Al, and Ti powders; The auxiliary fuel powder is selected from one or more of Si, Fe, Sn, and Mn powders; The inert inorganic filler is selected from one or more of metal oxides, silica, sulfate compounds, silicate compounds, and boron nitride.

3. The oxygen candle ignition composition according to claim 2, characterized in that: The inert inorganic filler is selected from one or more of zinc oxide, nickel oxide, titanium oxide, chromium oxide, aluminum oxide, silica, magnesium sulfate, calcium sulfate, calcium silicate, and boron nitride.

4. The oxygen candle ignition composition according to claim 1, 2 or 3, characterized in that: The particle size of the oxidizer powder is 60-200 mesh; the particle size of the fuel powder is 100-400 mesh; the particle size of the inert inorganic filler is not less than 800 mesh.

5. An oxygen candle ignition charge block, characterized in that: 20%-46% of oxidizer powder, 15%-32% of fuel powder, and 28%-56% of inert inorganic filler by mass percentage are dry-mixed evenly and then pressed into shape; The fuel powder is composed of main fuel powder and auxiliary fuel powder with a weight ratio of (1-8):

1.

6. The oxygen candle ignition charge block according to claim 5, characterized in that: The oxidizer powder is selected from one or more of sodium chlorate, sodium perchlorate, potassium chlorate, and potassium perchlorate, and the particle size is 60-200 mesh; The main fuel powder is selected from one or more of Mg, Al, and Ti powders, and the particle size is 100-400 mesh; the auxiliary fuel powder is selected from one or more of Si, Fe, Sn, and Mn powders, and the particle size is 100-400 mesh; The inert inorganic filler is selected from one or more of metal oxides, silica, sulfate compounds, silicate compounds, and boron nitride, and the particle size is not less than 800 mesh.

7. A method for preparing an oxygen candle ignition agent, characterized in that: It includes the following steps: S1. Weigh 20%-46% of oxidizer powder, 15%-32% of fuel powder, and 28%-56% of inert inorganic filler by mass percentage, and mix and screen to disperse the powder; the fuel powder is composed of main fuel powder and auxiliary fuel powder with a weight ratio of (1-8):1; S2. Pour the mixture under the sieve into a mixer, mix it, and pour it out after making it uniform to complete the dry mixing of the ignition charge; S3. Load the ignition charge after dry mixing into a mold and press it into shape.

8. The preparation method of the oxygen candle ignition composition according to claim 7, characterized in that: In step S1, the oxidizer powder is selected from one or more of sodium chlorate, sodium perchlorate, potassium chlorate, and potassium perchlorate, and the particle size is 60-200 mesh; The main fuel powder is selected from one or more of Mg, Al, and Ti powders, and the particle size is 100-400 mesh; the auxiliary fuel powder is selected from one or more of Si, Fe, Sn, and Mn powders, and the particle size is 100-400 mesh; The inert inorganic filler is selected from one or more of metal oxides, silica, sulfate compounds, silicate compounds, and boron nitride, and the particle size is not less than 800 mesh.

9. The preparation method of the oxygen candle ignition agent according to claim 7, characterized in that: In step S2, the mixing time is 5-10 min.

10. The preparation method of the oxygen candle ignition agent according to claim 7, characterized in that: In step S3, it is pressed using an automatic press, and the press pressure is 30 - 50 T / cm 2 , and after pressing and forming, the density of the igniter charge is 1.7 - 2.3 g / cm 3 .

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