Adsorption plugging fire preventing and extinguishing material and application thereof

Abstract

The invention relates to the technical field of coal mine underground plugging fire prevention and extinguishing and carbon sequestration, in particular to an adsorption plugging fire prevention and extinguishing material and application thereof. The adsorption plugging fire preventing and extinguishing material comprises a porous carrier and organic amine, the preparation method of the porous carrier comprises the following steps: uniformly mixing garbage bottom ash and slag to obtain a mixed material; dissolving a surfactant in water, stirring and foaming, then adding an alkali activator, and uniformly mixing to obtain an alkaline foaming solution; uniformly mixing the alkaline foaming liquid with the mixed material to obtain foaming slurry; curing the foaming slurry at normal temperature to obtain the porous carrier; the organic amine accounts for 5wt%-25wt% of the mass of the foaming slurry. The material is environment-friendly, the cost is low, the preparation is simple, an air leakage channel of a goaf can be blocked and carbon dioxide can be adsorbed at the same time, and when a fire occurs in an underground coal mine, the temperature of the surrounding environment rises, the adsorbed CO2 can be desorbed in time, and the fire preventing and extinguishing effect is achieved.

Description

Technical Field

[0001] The invention relates to the technical field of underground plugging, fire prevention and carbon fixation in coal mines, and in particular to an adsorption, plugging and fire prevention material and application thereof. Background Art

[0002] The increasing depth of coal mining has led to increasingly severe problems in fire prevention and extinguishing in mines. The air leakage plugging technology prevents oxygen from entering and controls air leakage by injecting leak-proof and fire-proof materials into the goaf, which is crucial to preventing the spread of fire and protecting underground equipment and personnel safety. At present, the commonly used air leakage plugging materials in mines are divided into two categories: organic and inorganic. Organic plugging materials mainly include polyurethane foam, phenolic foam and urea-formaldehyde foam, but they are expensive, flammable at high temperatures and produce harmful irritating gases. Among inorganic plugging materials, fly ash has poor plugging effect, long solidification time, slow strength growth, great environmental impact and limited scope of application; traditional ammonium salt gel will release toxic gases when forming colloid, and has poor compressive strength and toughness, will powder and crack after water loss, and the fire area is easy to reignite after fire extinguishing; cement-based materials are not only expensive, easy to shrink and crack, but also have problems of high energy consumption and high carbon emissions.

[0003] At the same time, with the global concern about CO2 emissions, carbon fixation technology has become a research hotspot. In the field of producing porous carbon dioxide adsorbents, the synthesis of most porous carbon dioxide adsorbents requires the use of multiple templates or calcination at high temperatures to form pores, resulting in cumbersome synthesis processes, long preparation cycles, and high costs, which limits large-scale industrial production. In addition, the common loading methods of solid amine adsorbents are grafting or impregnation, which is not conducive to field application; and the utilization rate of loaded amines in many solid amine adsorbents is low, so that the carbon dioxide adsorption capacity of the adsorbent needs to be further enhanced. The existing method of CO2 storage in coal mines is the mineralization of CO2. For example, patent CN114673552A passes CO2 into fly ash-based filling slurry, and reacts with calcium aluminosilicate therein to generate CaCO3 mineralization, but this method is a permanent storage of CO2. It is difficult to achieve CO2 desorption under general conditions. When a fire occurs in a coal mine, the sealed CO2 cannot be released in time for fire extinguishing, which limits its flexibility in practical applications such as mine fire extinguishing. Therefore, using solid waste as raw materials to prepare carbon adsorption leak-plugging and fire-extinguishing materials can not only realize the resource utilization of solid waste, but also plug leaks and prevent fires, and can also adsorb and seal carbon dioxide. When a fire occurs and the temperature rises, it can release carbon dioxide to play a fire-extinguishing role. It has important practical significance and application value. Summary of the invention

[0004] Based on the above content, the present invention uses solid waste as raw material to prepare a porous carbon dioxide adsorption and blocking fire extinguishing material loaded with organic amine based on municipal waste incineration bottom ash with high porosity and specific surface area, high adsorption performance and stability. The material has the characteristics of low cost, mild reaction conditions and easy preparation, and can be mass-produced and applied in coal mines.

[0005] To achieve the above object, the present invention provides the following solutions: One of the technical solutions of the present invention is an adsorption and blocking fire extinguishing material, comprising a porous carrier and an organic amine; The method for preparing the porous carrier comprises the following steps: Mixing garbage bottom ash and slag to obtain a mixed material; The surfactant is dissolved in water and foamed using a high-speed stirrer, and then an alkaline activator is added and mixed to obtain an alkaline foaming liquid; Mixing the alkaline foaming liquid and the mixed material to obtain a foaming slurry; Curing the foaming slurry at room temperature to obtain the porous carrier; The alkaline activator is a mixture of NaOH and water glass; The organic amine is tetraethylenepentamine, polyethyleneimine The organic amine accounts for 5wt%-25wt% of the mass of the foaming slurry.

[0006] The second technical solution of the present invention is the application of the above-mentioned adsorption, sealing and fire-proofing material in the goaf of underground coal mines.

[0007] The third technical solution of the present invention is the application of the above-mentioned adsorption and blocking fire extinguishing material in the adsorption and desorption of carbon dioxide.

[0008] The present invention discloses the following technical effects: The adsorption and blocking fire-fighting material prepared by the present invention with solid waste (garbage bottom ash and slag) as raw materials can not only block air leakage and prevent fire, but also adsorb and seal carbon dioxide. It can desorb CO2 at 46°C and can be used for fire extinguishing in coal mines.

[0009] The present invention uses two solid wastes, namely, alkali-activated garbage bottom ash and slag, as carriers, ensuring foaming and obtaining a stable porous product for adsorption while realizing a green and environmentally friendly material collection method.

[0010] The present invention applies a surfactant to an alkali excitation system, that is, under the premise of alkali excitation, AEC-9Na or OB-2 alkali-resistant surfactant is used to foam and mix with a mixture of garbage bottom ash and slag to prepare a foaming slurry, and the pore structure of the carrier is more developed in a physical-chemical composite foaming manner, thereby increasing the contact reaction surface with amine and CO2.

[0011] The process for preparing the porous carrier of the present invention is simple and the reaction conditions are mild. The prepared adsorption and blocking fire-proof extinguishing material has strong adsorption performance for carbon dioxide.

[0012] The present invention realizes the loading of amine by spraying organic amine on the porous carrier, which is convenient for practical application on site.

[0013] The invention not only uses environmentally friendly materials, has low cost and is simple to prepare, but can also simultaneously block air leakage channels in goaf areas and adsorb carbon dioxide. When a fire occurs underground in a coal mine, the ambient temperature rises and the adsorbed CO2 can be desorbed in time to achieve the effect of fire prevention and extinguishing. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0015] Figure 1 This is a microscopic magnified image of the internal pore structure of the pure chemical foaming carrier prepared in Example 1 of the present invention with a surfactant addition amount of 0; Figure 2 This is a diagram of the carrier foaming multiples of different base material (garbage bottom ash and slag) ratios when the surfactant addition amount prepared in Example 2 of the present invention is 0; Figure 3 This is a microscopic magnified image of the internal pore structure of the porous carrier prepared in Example 3 of the present invention; Figure 4 This is a diagram of the foaming multiples of the porous carrier prepared under different surfactant proportions in Example 3 of the present invention; Figure 5 This is a CO2-TPD analysis curve of a porous carrier loaded with 25 wt% TEPA prepared in Example 4 of the present invention; Figure 6 The CO2 desorption amount corresponding to the porous carrier loaded with different amounts of TEPA prepared in Examples 4 and 5 of the present invention; Figure 7 The present invention is a process flow chart for the preparation and application of the adsorption and blocking fire extinguishing material. DETAILED DESCRIPTION

[0016] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as limiting the present invention, but should be understood as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0017] It should be understood that the terms described in the present invention are only for describing a particular embodiment and are not intended to limit the present invention. In addition, for the numerical range in the present invention, it should be understood that each intermediate value between the upper and lower limits of the scope is also specifically disclosed. The intermediate value in any stated value or stated range, and each smaller range between any other stated value or intermediate value in the described range is also included in the present invention. The upper and lower limits of these smaller ranges can be independently included or excluded in the scope.

[0018] Unless otherwise indicated, all technical and scientific terms used herein have the same meanings as those generally understood by those skilled in the art. Although the present invention describes only preferred methods and materials, any methods and materials similar or equivalent to those described herein may also be used in the implementation or testing of the present invention. All documents mentioned in this specification are incorporated by reference to disclose and describe the methods and / or materials associated with the documents. In the event of a conflict with any incorporated document, the content of this specification shall prevail.

[0019] It will be apparent to those skilled in the art that various modifications and variations may be made to the specific embodiments of the present invention description without departing from the scope or spirit of the present invention. Other embodiments derived from the present invention description will be apparent to those skilled in the art. The present invention description and examples are exemplary only.

[0020] The words “include,” “including,” “have,” “contain,” etc. used in this document are open-ended terms, meaning including but not limited to.

[0021] The "normal temperature" mentioned in the present invention, unless otherwise specified, means 15-35°C.

[0022] The present invention utilizes the high aluminum content in the bottom ash of municipal waste incineration to carry out chemical foaming, and simultaneously adds a surfactant to cooperate with the foaming in the process of preparing a porous carrier, and injects the foaming slurry into the coal mine goaf in a grouting manner, and after curing at room temperature, sprays the organic amine solution onto the porous carrier in a spray manner to prepare an adsorption, plugging and fire-proofing material, thereby realizing the plugging and fire-proofing of the coal mine goaf.

[0023] The first aspect of the present invention provides an adsorption and blocking fire extinguishing material, comprising a porous carrier and an organic amine; The method for preparing the porous carrier comprises the following steps: Mixing garbage bottom ash and slag to obtain a mixed material; The surfactant is dissolved in water and foamed using a high-speed stirrer, and then an alkaline activator is added and mixed to obtain an alkaline foaming liquid; Mixing the alkaline foaming liquid and the mixed material to obtain a foaming slurry; Curing the foaming slurry at room temperature to obtain the porous carrier; The alkaline activator is a mixture of NaOH and water glass; The organic amine is tetraethylenepentamine, polyethyleneimine The organic amine accounts for 5wt%-25wt% of the mass of the foaming slurry.

[0024] In some embodiments of the present invention, the mass ratio of the garbage bottom ash to the slag is 9:1-1:9. More preferably, it is 1:(1-1.2). Both the garbage bottom ash and the slag are of S95 grade.

[0025] In some embodiments of the present invention, the surfactant is AEC-9Na or OB-2; the mass fraction of the surfactant in the foaming slurry is 0.001‰-0.1‰, and the mass fraction of the alkali activator is 20%-40%.

[0026] In some embodiments of the present invention, the mass ratio of NaOH to water glass is (0.1-1):2.

[0027] The modulus of the alkaline activator is regulated to be 0.6-1.8 by limiting the mass ratio of NaOH to water glass (the modulus of the alkaline activator is the ratio of the amount of SiO2 to Na2O).

[0028] The purpose of controlling the mass ratio of NaOH and water glass is to control the amount of alkali; the purpose of controlling the amount of alkali is to avoid the negative impact of excessive alkali content on the environment.

[0029] In some embodiments of the present invention, the mass ratio of the alkaline foaming liquid to the mixed material is (3-5):5.

[0030] The water-cement ratio of the foaming slurry is 0.4-0.8 (the water-cement ratio is the ratio of the total mass of H2O to the total mass of the mixed material (garbage bottom ash + slag)). The water-cement ratio is regulated by adjusting the mass ratio of the alkaline foaming liquid to the mixed material; because water glass originally contains a certain amount of water, a lower water-cement ratio cannot be achieved, and when the water-cement ratio is low, the setting time of the foaming slurry is too short, which makes it difficult to mix evenly and is not conducive to grouting; and a higher water-cement ratio will not only lead to enhanced slurry fluidity, but also lead to an unobvious foaming effect of the foaming slurry, and the formed carrier is brittle and easily broken into powder and slag, which is not conducive to forming a stable and strong structure. Therefore, the present invention limits the water-cement ratio of the foaming slurry to the above parameter range.

[0031] In some embodiments of the present invention, the curing is specifically standing at room temperature for 2 days.

[0032] In some specific embodiments of the present invention, the mixing method can be carried out using a high-speed stirrer (a planetary cement mortar mixer, whose stirring paddle has a low-speed rotation speed of 140±5r / min, a low-speed revolution speed of 62±5r / min; a high-speed rotation speed of 285±10r / min, and a high-speed revolution speed of 125±10r / min).

[0033] The second aspect of the present invention provides an application of the above-mentioned adsorption, sealing and fire-proofing material in the goaf of an underground coal mine.

[0034] In some embodiments of the present invention, the foaming slurry is injected into the goaf of a coal mine, and a porous carrier is obtained after curing at room temperature for 2 days; organic amine is sprayed on the porous carrier to seal and prevent fire in the goaf of the coal mine.

[0035] The third aspect of the present invention provides an application of the above-mentioned adsorption and blocking fire extinguishing material in carbon dioxide adsorption and desorption.

[0036] The technical solutions described in the present invention, unless otherwise specified, are all conventional solutions in the art, and the reagents or raw materials used, unless otherwise specified, are purchased from commercial channels or have been disclosed.

[0037] The garbage bottom ash and slag used in the embodiments of the present invention are both of grade S95.

[0038] The modulus of the base activator used in the embodiment of the present invention is 1.4.

[0039] The mass concentration of the surfactants used in the examples of the present invention is 2%, which are obtained through commercial sources.

[0040] The preparation and application process of the adsorption and blocking fire extinguishing material of the present invention is as follows: Figure 7 shown.

[0041] The technical solutions provided by the present invention are described in detail below in conjunction with the embodiments, but they should not be construed as limiting the protection scope of the present invention.

[0042] Example 1: Preparation of a pure chemical foaming carrier with zero surfactant addition 17.5 g of garbage bottom ash and 17.5 g of slag were taken and stirred at 200 r / min for 2 min to obtain a mixed material. 2.7131 g of NaOH and 21.3541 g of water glass were weighed and mixed with 3.2328 g of water to prepare an alkaline activator solution, which was poured into the mixed material, stirred at 400 rpm / min for 2 minutes, and then allowed to stand, and cured at room temperature for 2 days to obtain a pure chemical foaming carrier with 0 surfactant addition.

[0043] Figure 1This is a microscopic magnified image of the internal pore structure of the pure chemical foaming carrier with zero surfactant addition prepared in Example 1. It can be seen from the image that the aluminum contained in the bottom ash from the incineration of municipal waste reacts with the alkali in the alkali activator to release hydrogen, forming a clear pore structure inside the slurry.

[0044] Example 2: Preparation of carriers with different base material ratios with surfactant addition amount of 0 Take 24.5g of garbage bottom ash and 10.5g of slag, stir at 200r / min for 2min to evenly mix, and obtain a mixed material. Weigh 1.7441g of NaOH and 13.7276g of water glass and 8.3282g of water to evenly mix to prepare an alkaline activator solution, pour the alkaline activator solution into the above mixed material, stir at 400r / min for 2min, pour into a mold and let stand, and cure at room temperature for 2 days.

[0045] Figure 2 The foaming multiple diagram of the porous carrier obtained when the surfactant addition amount prepared in Example 2 is 0 and the ratios of garbage bottom ash and slag are different (that is, on the basis of Example 2, only the mass ratio of garbage bottom ash and slag is adjusted, and the other steps and parameters remain unchanged) shows that when the mass ratio of municipal waste incineration bottom ash: slag bottom material is 5:5, the foaming effect is the best, which is 132.70%, and the coagulation time is about 11 minutes and 45 seconds.

[0046] Example 3: Preparation of physical-chemical composite foaming carrier (porous carrier) with surfactant addition amount > 0 Take 17.5g of garbage bottom ash and 17.5g of slag, stir at 200r / min for 2min to mix evenly, and obtain a mixed material. Dissolve 11mL of surfactant OB-2 in 89mL of water, stir with a high-speed stirrer to prepare foam, weigh 2.7131g of NaOH and 21.3541g of water glass and mix evenly with 3.2328g of foam to obtain an alkaline foaming liquid. Mix the alkaline foaming liquid and the above mixed material, stir at 400r / min for 2 minutes (to obtain a foaming slurry), and then let it stand and cure at room temperature for 2 days.

[0047] Figure 3 This is a microscopic magnified image of the internal pore structure of the physical-chemical composite foaming carrier prepared in Example 3. It can be seen that the pore structure is distributed throughout the interior of the carrier. Compared with chemical foaming without adding surfactant, the pore structure of the carrier obtained by the physical-chemical composite foaming method is more developed.

[0048] Figure 4It is shown that on the basis of Example 3, the amount of foam added is kept unchanged, and the amount of surfactant added when preparing the foam is changed to change the foaming multiple of the porous carrier prepared by changing the proportion of surfactant. It can be seen that with the increase of the amount of surfactant added, the foaming multiple of the porous carrier also increases continuously. When the mass fraction of the surfactant in the foaming slurry is 0.001‰-0.01‰, the average foaming multiple of the porous carrier is 1.26-1.32 times; when the mass fraction of the added surfactant increases from 0.01‰ to 0.03‰, the foaming multiple of the carrier is also significantly improved; when the mass fraction of the added surfactant is 0.03‰-0.1‰, the average foaming multiple increases from 1.64 times to 2.34 times.

[0049] Example 4: Amine loading Preparation of foaming slurry: The only difference from Example 3 is that 7 mL of surfactant AEC-9Na is dissolved in 93 mL of water, and the foam is prepared by stirring with a high-speed stirrer.

[0050] The foaming slurry was injected into the coal mine goaf in the form of grouting, and solidified at room temperature for 2 days to obtain a porous carrier, and tetraethylenepentamine (TEPA) was sprayed to achieve organic amine loading; wherein the amount of tetraethylenepentamine sprayed was 25wt% of the mass of the foaming slurry, that is, the amine loading was 25wt%. A porous carrier loaded with 25wt% TEPA was obtained, that is, an adsorption and blocking fire extinguishing material.

[0051] like Figure 5 As shown in the figure, it is a CO2-TPD test spectrum of the porous carrier loaded with 25wt% TEPA prepared in Example 4 (surfactant mass fraction in the foaming slurry is 0.07‰). During the test, the chemical adsorption instrument first uses inert gas helium to purge the impurity gas originally adsorbed by the porous carrier sample, then introduces CO2 to make the material adsorb, and finally introduces helium for desorption and records the TCD signal. It can be seen from the figure that CO2 desorption can be achieved at 46°C; its desorption peak area is 746371.701, and the actual desorption amount represented is 3.106mmol / g.

[0052] Example 5

[0053] On the basis of Example 4, only the spraying amount of TEPA was adjusted to make the spraying amount of tetraethylenepentamine 0%, 5wt%, 10wt%, 15wt%, and 20wt% of the foaming slurry mass, and the other steps and parameters remained unchanged; the CO2 desorption amount of the above-mentioned porous carrier loaded with TEPA was counted (the test method was the same as that of Example 4), and the results were as follows Figure 6 Shown Figure 6The following is a graph of CO2 desorption corresponding to the porous carriers loaded with different amounts of TEPA in Examples 4 and 5. As can be seen from the figure, the CO2 desorption amount increased significantly after loading with amines, indicating that the introduction of amines significantly increased the ability of the porous carrier to adsorb CO2; with the increase in the amine loading, the CO2 desorption amount of the carrier also increased continuously, and when the amine loading reached 25wt% of the foaming slurry, the CO2 desorption amount of the porous carrier was the highest, which was 3.106mmol / g.

[0054] The embodiments described above are only descriptions of the preferred modes of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. An adsorption and blocking fire extinguishing material, characterized in that: including a porous support and an organic amine; The method for preparing the porous carrier comprises the following steps: Mixing garbage bottom ash and slag to obtain a mixed material; Dissolve the surfactant in water and stir to produce foam, then add the alkaline activator and mix well to obtain an alkaline foaming liquid; Mixing the alkaline foaming liquid and the mixed material to obtain a foaming slurry; Curing the foaming slurry at room temperature to obtain the porous carrier; The alkaline activator is a mixture of NaOH and water glass; The organic amine is tetraethylenepentamine or polyethyleneimine; The organic amine accounts for 5wt%-25wt% of the mass of the foaming slurry.

2. The adsorption and blocking fire extinguishing material according to claim 1, characterized in that: The mass ratio of the garbage bottom ash to the slag is 9:1-1:

9.

3. The adsorption and blocking fire extinguishing material according to claim 1, characterized in that: The surfactant is AEC-9Na or OB-2; the mass fraction of the surfactant in the foaming slurry is 0.001‰-0.1‰, and the mass fraction of the alkali activator is 20%-40%.

4. The adsorption and blocking fire extinguishing material according to claim 1, characterized in that: The mass ratio of NaOH to water glass is (0.1-1):

2.

5. The adsorption and blocking fire extinguishing material according to claim 1, characterized in that: The mass ratio of the alkaline foaming liquid to the mixed material is (3-5):

5.

6. The adsorption and blocking fire extinguishing material according to claim 1, characterized in that: The curing is specifically performed by standing at room temperature for 2 days.

7. Use of the adsorption, sealing and fire-proofing material as described in any one of claims 1 to 6 in the goaf of an underground coal mine.

8. The use according to claim 7, characterized in that: The foaming slurry described in claim 1 is injected into the coal mine goaf, and a porous carrier is obtained after curing at room temperature for 2 days; and organic amine is sprayed on the porous carrier to seal and prevent fire in the coal mine goaf.

9. Use of the adsorption and blocking fire extinguishing material according to any one of claims 1 to 6 in carbon dioxide adsorption and desorption.

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