Anti-aging hot aerosol fire extinguishing agent and preparation method therefor

Abstract

Disclosed are an anti-aging hot aerosol fire extinguishing agent and a preparation method therefor. The anti-aging hot aerosol fire extinguishing agent comprises 60-80% of an oxidizing agent, 2-25% of a high-fire-extinguishing capability reducing agent, 2-25% of a high-burning-rate reducing agent, and 5-15% of a binder. The preparation method comprises: premixing a high-fire-extinguishing capability reducing agent and a high-burning-rate reducing agent, and then carrying out ball milling to obtain a uniform, small-particle-size reducing agent mixture; mixing the mixture with an oxidizing agent and a binder; and adding anhydrous ethanol, mixing, granulating, and drying to obtain an anti-aging hot aerosol fire extinguishing agent. The anti-aging hot aerosol fire extinguishing agent prepared by the present invention has a long service life, high safety, and excellent fire extinguishing performance, and propellant grains do not develop expansion cracks after aging.

Description

Anti-aging thermal aerosol fire extinguishing agent and preparation method thereof Technical Field

[0001] The invention belongs to the technical field of high-performance fire extinguishing agent preparation, and particularly relates to an anti-aging thermal aerosol fire extinguishing agent and a preparation method thereof. Background Art

[0002] Aerosol fire extinguishing agents have been widely studied due to their high fire extinguishing efficiency, non-toxicity, lack of ozone depletion, and ability to be stored at atmospheric pressure. Aerosol fire extinguishing agents primarily consist of an oxidizing agent, a reducing agent, and a binder. They extinguish fires by generating a large amount of extinguishing medium through a combustion reaction. Aerosol fire extinguishing agents are categorized as hot aerosols and cold aerosols based on the temperature at which the aerosol is generated. Unlike cold aerosols, hot aerosols require a combustion reaction to produce the desired product, and the choice of reducing agent significantly impacts their fire extinguishing capabilities.

[0003] A single reducing agent can exhibit either high fire extinguishing ability or high burning rate, but not both, which limits the fire extinguishing performance of thermal aerosol fire extinguishing agents. If reducing agent components with two properties are simply mixed, the mixing uniformity of various raw materials in the fire extinguishing agent will be seriously affected. In addition, the thermal aerosol fire extinguishing agent pellets prepared using two reducing agents will show varying degrees of expansion or cracking in accelerated aging tests. This result will not only greatly reduce the fire extinguishing efficiency of the thermal aerosol fire extinguishing agent, but also shorten the storage life of the pellets. In severe cases, it will cause the fire extinguishing device to be pressurized during use, thereby causing safety problems.

[0004] Summary of the Invention

[0005] In response to the above technical problems, the present invention provides an anti-aging hot aerosol fire extinguishing agent and a preparation method thereof. Reducing agents with different properties are premixed and then ball-milled, which improves the problems of large differences in particle size and uneven mixing of different reducing agents, increases the service life of the explosive column, and ensures fire extinguishing efficiency and safety of use.

[0006] To achieve the above object, the present invention provides an anti-aging thermal aerosol fire extinguishing agent, comprising the following components by mass percentage: 60-80% oxidant, 2-25% high fire extinguishing ability reducing agent, 2-25% high burning rate reducing agent and 5-15% adhesive.

[0007] Preferably, the oxidant is any one or more of potassium nitrate, strontium nitrate, sodium nitrate and guanidine nitrate.

[0008] Preferably, the reducing agent with high fire extinguishing ability is nitrogen-containing organic matter.

[0009] More preferably, the nitrogen-containing organic compound is any one of urea, nitroguanidine, dicyandiamide, melamine, melamine cyanurate, p-nitrophenol, and p-phenylenediamine.

[0010] Preferably, the high burning rate reducing agent is an organic acid or an anhydride.

[0011] Further preferably, the organic acid is any one of ethylenediaminetetraacetic acid, phthalic acid, terephthalic acid, adipic acid, octadecanoic acid, ferulic acid, sinapic acid, citric acid, caffeic acid, sorbic acid, fumaric acid, benzoic acid, capric acid, oxalic acid, malonic acid, succinic acid, pimelic acid, suberic acid, tridecanedioic acid, hexadecanedioic acid, 2-hydroxysuccinic acid, maleic acid and isophthalic acid; and the acid anhydride is phthalic anhydride.

[0012] Preferably, the adhesive is any one of epoxy resin, phenolic resin, polyethylene glycol, polyester resin and shellac.

[0013] The present invention also provides a method for preparing an anti-aging thermal aerosol fire extinguishing agent, comprising the following steps:

[0014] (1) premixing a high fire extinguishing ability reducing agent and a high burning rate reducing agent, and ball milling the mixture to obtain a reducing agent mixture;

[0015] (2) sieving and mixing the oxidizing agent, the reducing agent mixture, and the binder to obtain a mixture;

[0016] (3) The mixture is mixed with anhydrous ethanol and stirred, and then sieved, granulated, and dried to obtain an anti-aging hot aerosol fire extinguishing agent.

[0017] Preferably, the premix in step (1) needs to be passed through a 100-mesh sieve first, the ball milling speed is 200-300 rpm / min, and the ball milling time is 12-18 min; the mass ratio of balls to materials during ball milling is 2:1.

[0018] Preferably, the sieve used in step (1) is 100 mesh.

[0019] Preferably, the mass of the anhydrous ethanol in step (3) is 5-10% of the total mass of the mixture, the sieve is 20 mesh, and the drying temperature is 50-55°C.

[0020] The beneficial effects of the present invention are:

[0021] 1. Combining a high fire extinguishing ability reducing agent and a high burning rate reducing agent, and mixing them by premixing and ball milling, so that the hot aerosol fire extinguishing agent has both high fire extinguishing ability and high burning rate. At the same time, the premixing and ball milling method can also overcome the problems of non-uniform particle size and uneven mixing of the two reducing agent components, avoid the expansion or cracking of the prepared fire extinguishing powder column after aging, and improve the anti-aging performance of the hot aerosol fire extinguishing agent.

[0022] 2. The hot aerosol fire extinguishing agent prepared by the present invention increases the service life of the powder column and ensures the fire extinguishing efficiency and safety of the powder column. DETAILED DESCRIPTION

[0023] The technical solutions of the present invention are further explained below with reference to specific embodiments. It is worth noting that the following embodiments are only preferred embodiments of the present invention and should not be construed as limiting the present invention. The scope of protection of the present invention shall be determined by the claims. Any modifications or substitutions made to the technical solutions of the present invention by those skilled in the art without creative effort shall fall within the scope of protection of the present invention.

[0024] Example 1

[0025] The invention discloses an anti-aging hot aerosol fire extinguishing agent, which has the following formula: 5% urea, 12% phthalic anhydride, 75% potassium nitrate and 8% epoxy resin.

[0026] Preparation method:

[0027] (1) Premixing a high fire extinguishing ability reducing agent and a high burning rate reducing agent through a 100-mesh sieve, and then planetary ball milling for 15 minutes at a speed of 300 rpm and a ball-to-material ratio of 2:1 to obtain a reducing agent mixture;

[0028] (2) adding an oxidizing agent and a binder to the reducing agent mixture, and mixing again through a 100-mesh sieve to obtain a mixture;

[0029] (3) adding 5% anhydrous ethanol to the mixture, stirring the mixture thoroughly to make it uniform, then passing the mixture through a 20-mesh sieve to form granules, and drying the granules at 50° C. to obtain a hot aerosol fire extinguishing agent, wherein the content of anhydrous ethanol in the hot aerosol fire extinguishing agent after drying is ≤1%.

[0030] Example 2

[0031] An anti-aging hot aerosol fire extinguishing agent has a formula of 8% nitroguanidine, 12% ethylenediaminetetraacetic acid, 72% sodium nitrate and 8% phenolic resin. The preparation method is the same as that of Example 1.

[0032] Example 3

[0033] An anti-aging hot aerosol fire extinguishing agent has a formula of 8% dicyandiamide, 17% phthalic acid, 50% potassium nitrate, 15% strontium nitrate and 10% polyester resin. The preparation method is the same as that of Example 1.

[0034] Example 4

[0035] An anti-aging hot aerosol fire extinguishing agent has the following formula: 10% melamine, 10% octadecanoic acid, 68% potassium nitrate, 2% guanidine nitrate and 10% shellac. The preparation method is the same as that of Example 1.

[0036] Example 5

[0037] An anti-aging hot aerosol fire extinguishing agent has a formula of 2% melamine cyanurate, 25% terephthalic acid, 63% sodium nitrate and 10% polyethylene glycol. The preparation method is the same as that of Example 1.

[0038] Example 6

[0039] An anti-aging hot aerosol fire extinguishing agent with a formula of 3% p-nitrophenol, 2% adipic acid, 80% guanidine nitrate and 15% phenolic resin.

[0040] Example 7

[0041] An anti-aging hot aerosol fire extinguishing agent has a formula of 15% p-phenylenediamine, 15% ethylenediaminetetraacetic acid, 40% potassium nitrate, 25% guanidine nitrate, and 5% polyester resin. The preparation method is the same as that of Example 1.

[0042] Comparative Example 1

[0043] The formula is the same as that of Example 1, except that the two reducing agents are directly mixed with the oxidizing agent and the binder without premixing and granulated.

[0044] Comparative Example 2

[0045] A hot aerosol fire extinguishing agent with the formula: 75% potassium nitrate, 17% urea and 8% epoxy resin.

[0046] Preparation method:

[0047] (1) mixing an oxidizing agent, a reducing agent, and a binder through a 100-mesh sieve to obtain a mixture;

[0048] (2) Add 5% anhydrous ethanol to the mixture, stir it thoroughly to make it uniform, and finally pass it through a 20-mesh sieve to granulate it, and dry it at 50° C. to obtain a hot aerosol fire extinguishing agent.

[0049] Comparative Example 3

[0050] A hot aerosol fire extinguishing agent with the formula of 75% potassium nitrate, 17% phthalic anhydride and 8% epoxy resin.

[0051] The preparation method is the same as that of Comparative Example 2.

[0052] Comparative Example 4

[0053] A hot aerosol fire extinguishing agent with the formula: 75% potassium nitrate, 17% urea and 8% epoxy resin.

[0054] Preparation method:

[0055] (1) The reducing agent was subjected to planetary ball milling at a speed of 300 rpm and a ball-to-material ratio of 2:1 for 15 min;

[0056] (2) adding an oxidizing agent and a binder to the mixture obtained in step (1), mixing through a 100-mesh sieve, and obtaining a mixture;

[0057] (3) Add 5% anhydrous ethanol and stir thoroughly to mix evenly, and finally granulate the mixture through a 20-mesh sieve and dry it at 50° C. to obtain a hot aerosol fire extinguishing agent.

[0058] Comparative Example 5

[0059] A hot aerosol fire extinguishing agent with the formula of 75% potassium nitrate, 17% phthalic anhydride and 8% epoxy resin.

[0060] The preparation method is the same as that of Comparative Example 4.

[0061] Results: 30 g of the hot aerosol fire extinguishing agent prepared in the above examples and comparative examples were respectively taken and pressed into cylindrical charge with a diameter of 32 mm at a pressure of 5 MPa. The charge was then assembled into a fire extinguishing device and finally subjected to an accelerated aging life test at 95°C for 56 days. After 56 days, the condition of the charge was observed, and a spraying experiment was carried out to test the spraying time, fire extinguishing concentration, and fire extinguishing time. The results are shown in Table 1:

[0062] Table 1 Spraying effect after aging test

[0063] While the hot aerosol fire extinguishing agents prepared using a single-component reducing agent (Comparative Examples 2 and 3) showed no abnormalities in the morphology of the pellets, their fire extinguishing efficiency was low. However, when a multi-component reducing agent was simply mixed by screening or stirring, the pellets produced exhibited significant expansion and cracking after aging at 95°C (Comparative Example 1), significantly reducing the device's discharge time and seriously impacting its safe use. Regardless of whether the single-component reducing agent was ball-milled before being combined with an oxidant and binder to form a hot aerosol fire extinguishing agent (Comparative Examples 2 and 4, and Comparative Examples 3 and 5, respectively), the resulting pellets showed no expansion or cracking.

[0064] Compared with the agents prepared by simply mixing single-component reducing agents and multi-component reducing agents, the hot aerosol fire extinguishing agent column prepared by premixing and then ball milling not only did not show expansion or cracking after aging at 95°C, but also effectively guaranteed the high fire extinguishing ability of the agent.

Claims

1. An anti-aging thermal aerosol fire extinguishing agent, characterized in that: The invention comprises the following components in percentage by mass: 60-80% of an oxidant, 2-25% of a reducing agent with high fire extinguishing ability, 2-25% of a reducing agent with high burning speed and 5-15% of a binder.

2. The anti-aging thermal aerosol fire extinguishing agent according to claim 1, characterized in that: The oxidant is any one or more of potassium nitrate, strontium nitrate, sodium nitrate and guanidine nitrate.

3. The anti-aging thermal aerosol fire extinguishing agent according to claim 1, characterized in that: The high fire extinguishing ability reducing agent is nitrogen-containing organic matter.

4. The anti-aging thermal aerosol fire extinguishing agent according to claim 3, characterized in that: The nitrogen-containing organic matter is any one of urea, nitroguanidine, dicyandiamide, melamine, melamine cyanurate, p-nitrophenol and p-phenylenediamine.

5. The anti-aging thermal aerosol fire extinguishing agent according to claim 1, characterized in that: The high burning rate reducing agent is an organic acid and anhydride.

6. The anti-aging thermal aerosol fire extinguishing agent according to claim 5, characterized in that: The organic acid is any one of ethylenediaminetetraacetic acid, phthalic acid, terephthalic acid, adipic acid, octadecanoic acid, ferulic acid, sinapinic acid, citric acid, caffeic acid, sorbic acid, fumaric acid, benzoic acid, capric acid, oxalic acid, malonic acid, succinic acid, pimelic acid, suberic acid, tridecanedioic acid, hexadecanedioic acid, 2-hydroxysuccinic acid, maleic acid and isophthalic acid; and the acid anhydride is phthalic anhydride.

7. The anti-aging thermal aerosol fire extinguishing agent according to claim 1, characterized in that: The adhesive is any one of epoxy resin, phenolic resin, polyethylene glycol, polyester resin and shellac.

8. A method for preparing the anti-aging thermal aerosol fire extinguishing agent according to any one of claims 1 to 7, characterized in that: The following steps are involved: (1) premixing a high fire extinguishing ability reducing agent and a high burning rate reducing agent, and ball milling to obtain a reducing agent mixture; (2) sieving and mixing the oxidant, the reducing agent mixture and the binder to obtain a mixture; (3) The mixture is mixed with anhydrous ethanol and stirred, and then sieved, granulated, and dried to obtain an anti-aging hot aerosol fire extinguishing agent.

9. The preparation method according to claim 8, characterized in that: The premixing in step (1) needs to be passed through a 100-mesh screen first, the ball milling speed is 200-300 rpm / min, and the ball milling time is 12-18 min; the mass ratio of balls to materials during ball milling is 2:

1.

10. The preparation method according to claim 8, characterized in that: The sieve in step (1) is 100 mesh; The mass of the anhydrous ethanol in step (3) is 5-10% of the total mass of the mixture, the sieve is 20 mesh, and the drying temperature is 50-55°C.

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