Environmentally friendly anti-sol gel foam extinguishing agent

Abstract

The application discloses an environment-friendly anti-dissolution gel foam extinguishing agent, which is composed of a foaming agent, a gelling agent, a crosslinking agent and a flame retardant, wherein the foaming agent is alkyl polyglycoside APG0810, the gelling agent is kappa-carrageenan, the crosslinking agent is gluconolactone, and the flame retardant is tributyl phosphate. Compared with existing foam extinguishing agents, the anti-dissolution gel foam extinguishing agent has longer storage stability, fewer component types, better anti-dissolution and better extinguishing performance. In addition, the anti-dissolution gel foam extinguishing agent has lower manufacturing cost, simple preparation process and is more convenient for large-scale industrial production.

Description

Technical Field

[0001] This invention belongs to the field of fire extinguishing agent technology, specifically relating to an environmentally friendly alcohol-resistant gel foam fire extinguishing agent. Background Technology

[0002] With the rapid development of the energy and chemical industry, the large-scale storage and transportation of polar organic solvents such as alcohols and ketones are becoming increasingly common, significantly increasing their fire risk. For these types of polar liquid fires, commonly used foam extinguishing agents include protein foam, fluoroprotein foam, film-forming fluoroprotein foam (AFFF), and alcohol-resistant foam extinguishing agents. However, traditional foam extinguishing agents have the following problems:

[0003] 1. Environmental pollution issues. Fluorinated surfactants are difficult to degrade in the environment and have been gradually restricted or banned by international conventions.

[0004] 2. Insufficient solvent resistance. Polar organic solvents are easily miscible with foam water, causing the foam to collapse rapidly and significantly reducing extinguishing efficiency.

[0005] 3. Poor stability. Some foam extinguishing agents are prone to stratification and sedimentation during long-term storage, affecting their effectiveness.

[0006] 4. High manufacturing costs. Some compound systems have complex components and high costs, which is not conducive to large-scale promotion and application.

[0007] Therefore, there is an urgent need to develop a foam extinguishing agent that is simple in composition, stable in storage, environmentally friendly, and can maintain good solvent resistance in polar organic solvent fires, in order to replace existing fluorinated foam products. Summary of the Invention

[0008] To address the shortcomings of the existing technologies, this invention provides an environmentally friendly alcohol-resistant gel foam fire extinguishing agent. This invention utilizes the synergistic effect of natural polysaccharide gelling agents, green surfactants, and biodegradable crosslinking agents to significantly improve alcohol resistance and stability while ensuring good foaming performance. Furthermore, it achieves chemical flame retardancy through a small amount of flame-retardant additives, thus balancing fire extinguishing efficiency with environmental friendliness.

[0009] The alcohol-resistant gel foam fire extinguishing agent of the present invention is composed of a compound of foaming agent, gelling agent, crosslinking agent and flame retardant, wherein each component comprises, by weight percentage:

[0010] 2-5% foaming agent, 1-3% gelling agent, 1-3% crosslinking agent, 1-2% flame retardant, and the remainder is water.

[0011] Further preferred options are:

[0012] 2% foaming agent, 1% gelling agent, 1% crosslinking agent, 1% flame retardant, and the balance is water.

[0013] The foaming agent is a nonionic surfactant, alkyl glycoside APG0810.

[0014] The gelling agent is κ-carrageenan.

[0015] The crosslinking agent is gluconolactone (GDL), which can be gradually hydrolyzed in the foam solution to release H. + Ions neutralize the alkaline environment generated by alkyl glycoside APG0810 in the system, regulate the pH of the solution, promote the protonation of κ-carrageenan molecular chains, and induce them to form a stable three-dimensional gel network structure.

[0016] The flame retardant is preferably tributyl phosphate (TBP), which can decompose and release PO· and HPO· free radicals in the flame zone, thus blocking the combustion chain reaction.

[0017] The preparation method of the alcohol-resistant gel foam fire extinguishing agent of the present invention includes the following steps:

[0018] Step 1: Add the foaming agent and flame retardant to room temperature deionized water, stir and mix evenly to form a preliminary foaming solution;

[0019] Step 2: Add the gelling agent to deionized water at 70~80℃, heat and stir until completely dissolved, and let it cool naturally to room temperature to obtain a uniform and transparent gelling agent solution.

[0020] Step 3: Mix the preliminary foaming liquid obtained in Step 1 with the gelling agent solution obtained in Step 2, and form a homogeneous mixed solution under stirring conditions;

[0021] Step 4: Slowly add the crosslinking agent to the system obtained in Step 3, and continue stirring to mix evenly to obtain the finished environmentally friendly alcohol-resistant gel foam fire extinguishing agent.

[0022] When mixing, mechanical stirring or air blowing can be used, and the foaming ratio should be controlled between 3 and 6.

[0023] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0024] 1. Compared with traditional fluorinated foam fire extinguishing agents: Traditional alcohol-resistant foams often use fluorinated surfactants (such as fluorocarbon surfactants) as key components. Although they have good alcohol resistance, they are difficult to degrade and pose an environmental risk of persistent organic pollutants (POPs). This invention does not use any fluorinated surfactants and uses the biodegradable alkyl glycoside APG0810 as a foaming agent, avoiding secondary environmental pollution at the source and conforming to international environmental protection trends.

[0025] 2. Compared with ordinary protein / synthetic foam extinguishing agents: Protein foam and some synthetic foam extinguishing agents are rapidly destroyed in polar liquid fires and have insufficient solvent resistance. This invention significantly improves the stability of foam on the surface of polar organic solvents by forming a three-dimensional gel film with κ-carrageenan and glucono-delta-lactone, preventing the absorption of the foam's aqueous phase and thus maintaining the integrity of the cover layer.

[0026] 3. Compared with existing solvent-resistant compound systems: Some existing solvent-resistant systems use complex polymers and multiple additives, resulting in complex system structure, poor foam liquid stability, and a tendency to stratification or precipitation during storage, as well as high manufacturing costs. The system components used in this invention consist only of alkyl glycoside APG0810 + κ-carrageenan + GDL and a small amount of TBP, with a simple formulation, widely available raw materials, simple preparation process, and environmental friendliness. This system is a gel-like solid at room temperature, which is beneficial for storage and transportation. When the temperature rises to about 50°C, it can change from a gel state to a liquid state, and this phase transition process has no significant impact on fire extinguishing performance, exhibiting excellent thermal reversibility and good system stability.

[0027] 4. Ordinary alcohol-resistant foam extinguishing agents mainly rely on physical isolation and lack chemical flame-suppressing mechanisms. This invention introduces a low dose of tributyl phosphate (TBP), which pyrolyzes in the flame zone to generate PO· and HPO· free radicals, effectively blocking the combustion chain reaction and achieving a dual extinguishing effect of "physical coverage + chemical flame suppression". Attached Figure Description

[0028] Figure 1 This is a demonstration of the small-scale fire extinguishing and solvent resistance effects of the foam prepared in this embodiment of the invention.

[0029] Figure 2 This is a SEM microstructure image of the foam prepared in an embodiment of the present invention.

[0030] Figure 3 This is a schematic diagram showing the solidification of the foam liquid prepared in an embodiment of the present invention after cooling and standing.

[0031] Figure 4 This is a demonstration of the fire extinguishing performance test results of the foam prepared in the embodiments of the present invention.

[0032] Figure 5 The test results of the anti-reignition performance of the foam prepared in the embodiments of the present invention are shown. Detailed Implementation

[0033] The present invention will be further described below with reference to embodiments, but this is not intended to limit the scope of protection of the present invention.

[0034] Example 1:

[0035] The preparation method of the environmentally friendly alcohol-resistant gel foam fire extinguishing agent in this embodiment includes the following steps:

[0036] Step 1: Select Formulation. This alcohol-resistant gel foam extinguishing agent consists of a foaming agent, a gelling agent, a crosslinking agent, and a flame retardant, comprising, by weight percentage:

[0037] 2% foaming agent, 1% gelling agent, 1% crosslinking agent, 1% flame retardant, and the balance is water.

[0038] The foaming agent is a nonionic surfactant alkyl glycoside APG0810 (added in the form of a 50wt% aqueous solution); the gelling agent is κ-carrageenan; the crosslinking agent is gluconolactone (GDL), which can gradually hydrolyze to release H⁺ ions, neutralize the alkaline environment, and induce κ-carrageenan to form a three-dimensional gel network; the flame retardant is preferably tributyl phosphate (TBP), which can decompose and release PO· and HPO· free radicals in the flame zone, blocking the combustion chain reaction.

[0039] Step 2: Preparation of foaming liquid

[0040] Step 2.1: Add 400 ml of 50% APG0810 aqueous solution and 100 ml of TBP to 10 L of room temperature deionized water, and mix them evenly on a magnetic stirrer at 800 rpm to form a preliminary foaming solution;

[0041] Step 2.2: Weigh 100 g of κ-carrageenan and add it to deionized water at 70~80℃. Heat and stir at the same stirring rate until completely dissolved, and then let it cool naturally to room temperature to obtain a uniform and transparent κ-carrageenan solution.

[0042] Step 2.3: Mix the preliminary foaming solution obtained in Step 2.1 with the κ-carrageenan solution obtained in Step 2.2, and form a homogeneous mixture under stirring at 800 rpm;

[0043] Step 2.4: Weigh 100 g of GDL and slowly add it to the mixture in Step 2.3. After stirring and mixing evenly at 800 rpm, 10 L of finished environmentally friendly alcohol-resistant gel foam fire extinguishing agent will be obtained.

[0044] Among them, GDL slowly hydrolyzes and releases H + Ions, as shown in Equation 1 below.

[0045] GDL + H₂O → Gluconic acid + H₂O + (1)

[0046] These H + It can react with the negative charge (-SO3) on the κ-carrageenan molecular chain. - The combination of these molecules partially protonates them, as shown in Equation 2 below.

[0047] -SO3 - +H + +→-SO3H (2)

[0048] After charge neutralization, the electrostatic repulsion between the molecular chains weakens, making it easier for the chains to approach each other and form intermolecular crosslinks through non-covalent interactions such as hydrogen bonds and van der Waals forces. This promotes the reconstruction of the double helix structure. As the double helix further aggregates and entangles, a continuous three-dimensional network gel structure is gradually formed, effectively enhancing the structural stability and anti-dissolution properties of the foam film.

[0049] Step 2.5: Place the foam solution obtained in Step 2.4 into a mixer and stir at 3000 rpm for 2 minutes to obtain uniform foam with a foaming ratio of 5.2. Subsequently, small-scale fire extinguishing experiments and alcohol resistance tests were conducted, and the results are as follows: Figure 1 As shown in the figure, no ethanol contamination was observed after the foam was removed, indicating that the prepared gel foam has excellent solvent resistance.

[0050] Step 2.6: The foam obtained in Step 2.5 is subjected to vacuum freeze-drying and its microstructure is observed under a 200x microscope. A distinct three-dimensional network gel structure is visible, such as... Figure 2 As shown.

[0051] Step 2.7: Fill the container with the foam liquid obtained in Step 2.4 and let it stand for about 6 hours. It will naturally solidify to form a solid gel. Figure 3 When the gel was heated in a 50°C water bath, the system returned to a liquid state, exhibiting obvious temperature-sensitive thermal reversible behavior.

[0052] Step 2.8: Add the heated and reliquefied foam liquid from Step 2.7 to the compressed air foam system, and conduct fire extinguishing performance and anti-reignition performance tests according to the GB15301 standard for foam extinguishing agents. In the test, 9L of ethanol was added and pre-ignited for 120 seconds. Foam spraying began at 3:52 in the DV recording and the flame was completely extinguished by 4:38, with an extinguishing time of 46 seconds. Figure 4 This is significantly better than the national standard requirement of less than 120 seconds. Subsequently, the flame-retardant canister was ignited at 6:39 in the DV recording, and the flame continued to spread to the entire oil pan until it was completely covered at 25:35, with a reignition time of 18 minutes and 56 seconds. Figure 5 This indicates that the prepared extinguishing agent has excellent extinguishing efficiency and anti-reignition performance.

[0053] To verify the screening process and superior performance of the raw material components for the solvent-resistant fire extinguishing agent proposed in this invention, several comparative examples were designed and implemented as follows:

[0054] Example 2:

[0055] Add 400 ml of 50 wt% aqueous solution of APG0810, 100 g of κ-carrageenan and 10 L of deionized water to a reaction vessel, heat to 70 °C at a stirring rate of 800 rpm and continue stirring until the system is completely dissolved and a homogeneous foam extinguishing agent is formed.

[0056] Example 3:

[0057] Add 400 ml of APG0810 50wt% aqueous solution, 100 g κ-carrageenan, 100 g GDL and 10 L of deionized water to the reaction vessel, heat to 70°C at 800 rpm and continue stirring until the system is completely dissolved and a homogeneous foam extinguishing agent is formed.

[0058] Example 4:

[0059] Add 400 ml of APG0810 50wt% aqueous solution, 100 g of sodium alginate, 100 g of GDL and 10 L of deionized water to the reaction vessel, heat to 70°C at 800 rpm and continue stirring until the system is completely dissolved and a homogeneous foam extinguishing agent is formed.

[0060] The fire extinguishing performance of the above Examples 1-4 and the purchased commercial AFFF / AR fire extinguishing agent was tested in accordance with the national standard GB15308-2025 "Foam Fire Extinguishing Agents". Table 1 below shows the fire extinguishing performance test results of the fire extinguishing agents prepared in the embodiments of the invention.

[0061]

[0062] Table 1 compares the key parameters of the fire extinguishing performance of the four examples and the commercial AFFF / AR fire extinguishing agent, including solvent resistance, pH value, extinguishing time, and reignition resistance time. Table 1 shows that Examples 1-3 all exhibit solvent resistance, while Example 4 does not, indicating that the system using κ-carrageenan as a gelling agent has superior solvent resistance compared to the system primarily using sodium alginate. Secondly, it can be observed that the pH of Example 2 is 11.2, indicating an alkaline environment in the foam solution, which does not meet the national standard range of 6.0-9.5. Regarding fire extinguishing performance, Example 1 has the shortest extinguishing time (46s), superior to the commercial AFFF / AR fire extinguishing agent (60s). In terms of reignition resistance, the reignition resistance times of Examples 1-3 all exceed 15 minutes, significantly better than the standard requirement (≥10 minutes) and AFFF / AR (14 minutes 23 seconds), indicating excellent fuel isolation and heat suppression capabilities. In summary, Example 1 performed best, exhibiting characteristics of low pH value, rapid fire extinguishing, and long-lasting resistance to reignition. This verifies the significant performance advantages and engineering application potential of the alcohol-resistant foam system constructed in this study for extinguishing alcohol-based fires.

Claims

1. An environmentally friendly alcohol-resistant gel foam fire extinguishing agent, characterized in that: The anti-alcohol gel foam fire extinguishing agent is composed of a compound of components including a foaming agent, a gelling agent, a crosslinking agent and a flame retardant. Each component includes, by weight percentage: 2-5% foaming agent, 1-3% gelling agent, 1-3% crosslinking agent, 1-2% flame retardant, and the balance being water. The foaming agent is a nonionic surfactant, alkyl glycoside APG0810; The gelling agent is κ-carrageenan; The crosslinking agent is gluconolactone; The flame retardant is tributyl phosphate.

2. The environmentally friendly alcohol-resistant gel foam fire extinguishing agent according to claim 1, characterized in that: The components, by weight percentage, include: 2% foaming agent, 1% gelling agent, 1% crosslinking agent, 1% flame retardant, and the balance being water.

3. The preparation method of the environmentally friendly alcohol-resistant gel foam fire extinguishing agent according to claim 1 or 2, characterized in that... Includes the following steps: Step 1: Add the foaming agent and flame retardant to room temperature deionized water, stir and mix evenly to form a preliminary foaming solution; Step 2: Add the gelling agent to deionized water at 70~80℃, heat and stir until completely dissolved, and let it cool naturally to room temperature to obtain a uniform and transparent gelling agent solution. Step 3: Mix the preliminary foaming liquid obtained in Step 1 with the gelling agent solution obtained in Step 2, and form a homogeneous mixed solution under stirring conditions; Step 4: Slowly add the crosslinking agent to the system obtained in Step 3, and continue stirring to mix evenly to obtain the environmentally friendly alcohol-resistant gel foam fire extinguishing agent.

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