Adsorptive plugging and fire extinguishing material and application thereof

Abstract

The present application relates to coal mine sealing fire prevention and carbon sequestration technology field, especially to a kind of adsorption sealing fire prevention and extinguishing material and its application.The adsorption sealing fire prevention and extinguishing material includes porous carrier and organic amine;The preparation method of the porous carrier includes the following steps: mixing garbage bottom ash and slag uniformly, to obtain mixture material;Surfactant is dissolved in water, stirring and foaming, then adding alkali activator and mixing uniformly, to obtain alkaline foaming liquid;The alkaline foaming liquid is mixed with the mixture material to obtain foaming slurry;The foaming slurry is cured at room temperature, to obtain the porous carrier;The organic amine accounts for 5wt%-25wt% of the mass of the foaming slurry.The present application not only takes environmental protection, low cost, simple preparation, but also can seal gob air leakage channel at the same time, and adsorb carbon dioxide, when coal mine fire occurs, ambient temperature rises, and the adsorbed CO2 can be promptly desorbed, to achieve the effect of fire prevention.

Description

Technical Field

[0001] This invention relates to the field of underground coal mine sealing, fire prevention and extinguishing technology and carbon fixation technology, and in particular to an adsorption sealing and fire prevention and extinguishing material and its application. Background Technology

[0002] The increasing depth of coal mining has led to increasingly severe fire prevention and extinguishing problems in mines. Air leakage sealing technology, which involves injecting fire-prevention and sealing materials into the goaf to prevent oxygen entry and control air leakage, is crucial for preventing the spread of fire and protecting underground equipment and personnel. Currently, commonly used air leakage sealing materials in mines are divided into two main categories: organic and inorganic. Organic sealing materials mainly include polyurethane foam, phenolic foam, and urea-formaldehyde foam, but they are expensive and flammable at high temperatures, producing harmful and irritating gases. Among inorganic sealing materials, fly ash has poor sealing effect, long setting time, slow strength gain, is greatly affected by the environment, and has limited applicability; traditional ammonium salt gels release toxic gases when forming colloids, have poor compressive strength and toughness, and will pulverize and crack after water loss, making the fire zone prone to reignition after extinguishing; while cement-based materials are not only expensive and prone to shrinkage and cracking, but also have high energy consumption and high carbon emissions.

[0003] Meanwhile, with global attention focused on CO2 emissions, carbon sequestration technology has become a research hotspot. In the field of porous carbon dioxide adsorbent materials, the synthesis of most porous carbon dioxide adsorbent materials requires the use of various template agents or calcination at high temperatures to create pores, resulting in cumbersome synthesis processes, long preparation cycles, and high costs, limiting large-scale industrial production. Furthermore, common solid amine adsorbent loading methods are grafting or impregnation, which are not suitable for field applications; and the utilization rate of loaded amines in many solid amine adsorbents is low, meaning the carbon dioxide adsorption capacity of the adsorbents needs further enhancement. Currently, the common method for CO2 sequestration in coal mines is CO2 mineralization, such as patent CN114673552A, which introduces CO2 into fly ash-based filling slurry, reacting it with calcium aluminosilicate to generate CaCO3. However, this method permanently sequesters CO2, making desorption difficult under normal conditions. When a fire occurs in a coal mine, the sequestered CO2 cannot be released in time for firefighting, limiting its flexibility in practical applications such as mine fire suppression. Therefore, using solid waste as raw material to prepare carbon adsorption leak-sealing and fire-extinguishing materials can not only realize the resource utilization of solid waste, but also seal leaks and extinguish fires, and adsorb and store carbon dioxide. When a fire occurs and the temperature rises, it can release carbon dioxide to play a fire-extinguishing role, which has important practical significance and application value. Summary of the Invention

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

[0005] To achieve the above objectives, the present invention provides the following solution:

[0006] One of the technical solutions of this invention is an adsorption and sealing fire extinguishing material, comprising a porous carrier and an organic amine;

[0007] The method for preparing the porous support includes the following steps:

[0008] The waste bottom ash and slag are mixed evenly to obtain a mixture;

[0009] The surfactant is dissolved in water and foamed using a high-speed stirrer. Then, an alkaline activator is added and mixed well to obtain an alkaline foaming liquid.

[0010] The alkaline foaming liquid is mixed with the mixture to obtain a foaming slurry;

[0011] The foaming slurry is cured at room temperature to obtain the porous carrier;

[0012] The alkaline activator is a mixture of NaOH and water glass;

[0013] The organic amine is tetraethylenepentamine or polyethyleneimine.

[0014] The organic amine accounts for 5wt%-25wt% of the mass of the foaming slurry.

[0015] The second technical solution of this invention is the application of the above-mentioned adsorption, sealing, fire prevention and extinguishing materials in the goaf of underground coal mines.

[0016] The third technical solution of this invention is the application of the above-mentioned adsorption, sealing, fire extinguishing materials in carbon dioxide adsorption and desorption.

[0017] The present invention discloses the following technical effects:

[0018] This invention relates to an adsorption-sealing fire-extinguishing material prepared from solid waste (garbage bottom ash and slag). This material can both seal air leaks and extinguish fires, and adsorb and store carbon dioxide. It can desorb CO2 at 46℃ and can be used for fire extinguishing in coal mines.

[0019] This invention uses two solid wastes, alkali-activated bottom ash and slag, as carriers, ensuring foaming and the production of stable porous products for adsorption while achieving a green and environmentally friendly material sourcing method.

[0020] This invention applies surfactants to an alkaline-activated system. Specifically, under alkaline activation, an alkaline-resistant surfactant, AEC-9Na or OB-2, is used to foam a mixture of waste bottom ash and slag to prepare a foaming slurry. This physical-chemical composite foaming method enhances the pore structure of the carrier and increases the contact surface with amines and CO2.

[0021] The present invention provides a simple process for preparing porous carriers under mild reaction conditions, and the resulting adsorption-sealing fire extinguishing material exhibits strong adsorption performance for carbon dioxide.

[0022] This invention uses the method of spraying organic amines onto a porous carrier to achieve amine loading, which facilitates practical field application.

[0023] This invention is not only environmentally friendly and inexpensive to use, but also simple to prepare. It can also simultaneously seal the air leakage channels in the goaf and adsorb carbon dioxide. When a fire occurs in the coal mine, the ambient temperature rises and the adsorbed CO2 can be desorbed in time, achieving the effect of fire prevention and extinguishing. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 This is a magnified micrograph of the internal pore structure of the pure chemical foaming carrier with zero surfactant added, prepared in Example 1 of the present invention.

[0026] Figure 2 The foaming ratio of the carrier with different substrate (garbage bottom ash and slag) ratios when the surfactant addition amount is 0, as shown in Example 2 of the present invention;

[0027] Figure 3 This is a magnified micrograph of the internal pore structure of the porous carrier prepared in Example 3 of the present invention;

[0028] Figure 4 This is a graph showing the foaming ratio of the porous carriers prepared under different surfactant ratios in Example 3 of the present invention.

[0029] Figure 5 This is a CO2-TPD analysis curve of the porous carrier loaded with 25wt% TEPA prepared in Example 4 of the present invention;

[0030] Figure 6 This is a graph showing the CO2 desorption amount corresponding to the porous carriers with different amounts of TEPA prepared in Examples 4 and 5 of this invention;

[0031] Figure 7 This is a process flow diagram of the preparation and application of the adsorption-sealing fire prevention and extinguishing material of the present invention. Detailed Implementation

[0032] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as a limitation of the present invention, but rather as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0033] It should be understood that the terminology used in this invention is merely for describing particular embodiments and is not intended to limit the invention. Furthermore, with respect to numerical ranges in this invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Any stated value or intermediate value within a stated range, as well as each smaller range between any other stated value or intermediate value within said range, is also included in this invention. The upper and lower limits of these smaller ranges may be independently included or excluded from the range.

[0034] Unless otherwise stated, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. While only preferred methods and materials have been described herein, any methods and materials similar or equivalent to those described herein may be used in the implementation or testing of this invention. All references to this specification are incorporated by way of citation to disclose and describe methods and / or materials associated with those references. In the event of any conflict with any incorporated reference, the content of this specification shall prevail.

[0035] Various modifications and variations can be made to the specific embodiments described in this specification without departing from the scope or spirit of the invention, as will be apparent to those skilled in the art. Other embodiments derived from this specification will also be readily apparent to those skilled in the art. This specification and embodiments are merely exemplary.

[0036] The terms “include,” “including,” “have,” “contain,” etc., used in this article are all open-ended terms, meaning that they include but are not limited to.

[0037] Unless otherwise specified, "room temperature" in this invention refers to 15-35℃.

[0038] This invention utilizes the high aluminum content in the bottom ash of municipal solid waste incineration for chemical foaming. Simultaneously, surfactants are added during the preparation of the porous carrier to synergistically foam the material. The foaming slurry is injected into the goaf of a coal mine by grouting. After curing at room temperature, an organic amine solution is sprayed onto the porous carrier to prepare an adsorption, sealing, fire prevention and extinguishing material, thereby achieving fire prevention and extinguishing in the goaf of a coal mine.

[0039] The first aspect of this invention provides an adsorption-blocking fire extinguishing material, comprising a porous carrier and an organic amine;

[0040] The method for preparing the porous support includes the following steps:

[0041] The waste bottom ash and slag are mixed evenly to obtain a mixture;

[0042] The surfactant is dissolved in water and foamed using a high-speed stirrer. Then, an alkaline activator is added and mixed well to obtain an alkaline foaming liquid.

[0043] The alkaline foaming liquid is mixed with the mixture to obtain a foaming slurry;

[0044] The foaming slurry is cured at room temperature to obtain the porous carrier;

[0045] The alkaline activator is a mixture of NaOH and water glass;

[0046] The organic amine is tetraethylenepentamine or polyethyleneimine.

[0047] The organic amine accounts for 5wt%-25wt% of the mass of the foaming slurry.

[0048] In some embodiments of the present invention, the mass ratio of the waste bottom ash to the slag is 9:1 to 1:9. More preferably, it is 1:(1-1.2). Both the waste bottom ash and the slag are S95 grade.

[0049] 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%.

[0050] In some embodiments of the present invention, the mass ratio of NaOH to water glass is (0.1-1):2.

[0051] The modulus of the alkali activator is controlled to be 0.6-1.8 by limiting the mass ratio of NaOH to water glass (the modulus of the alkali activator is the molar ratio of SiO2 to Na2O).

[0052] The purpose of controlling the mass ratio of NaOH to water glass is to control the amount of alkali added; the purpose of controlling the amount of alkali added is to avoid the negative environmental impact of excessively high alkali content.

[0053] In some embodiments of the present invention, the mass ratio of the alkaline foaming liquid to the mixture is (3-5):5.

[0054] 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 materials (garbage bottom ash + slag)). The water-cement ratio is controlled by adjusting the mass ratio of the alkaline foaming liquid to the mixed materials. Because water glass originally contains a certain amount of water, a lower water-cement ratio cannot be achieved. Furthermore, a low water-cement ratio results in a short setting time for the foaming slurry, making it difficult to mix evenly and hindering grouting. Conversely, a high water-cement ratio not only increases the fluidity of the slurry but also leads to an insignificant foaming effect and a brittle, easily broken, carrier, unsuitable for forming a stable and robust structure. Therefore, this invention limits the water-cement ratio of the foaming slurry to the above-mentioned range.

[0055] In some embodiments of the present invention, the curing specifically involves standing at room temperature for 2 days.

[0056] In some specific embodiments of the present invention, the mixing method can be carried out by using a high-speed mixer (planetary cement mortar mixer, whose mixing 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).

[0057] A second aspect of the present invention provides the application of the above-mentioned adsorption, sealing, fire extinguishing material in the goaf of an underground coal mine.

[0058] In some embodiments of the present invention, the above-mentioned foaming slurry is injected into the goaf area of ​​a coal mine and cured at room temperature for 2 days to obtain a porous carrier; organic amine is sprayed onto the porous carrier to achieve sealing and fire prevention in the goaf area of ​​the coal mine.

[0059] A third aspect of the present invention provides an application of the above-mentioned adsorption-blocking fire extinguishing material in carbon dioxide adsorption-desorption.

[0060] Unless otherwise specified, the technical solutions described in this invention are all conventional solutions in the field, and the reagents or raw materials used are all purchased from commercial channels or are publicly available unless otherwise specified.

[0061] The waste bottom ash and slag used in the embodiments of this invention are both S95 grade.

[0062] The modulus of the alkali activator used in the embodiments of the present invention is 1.4.

[0063] The surfactants used in the embodiments of this invention all have a mass concentration of 2% and are obtained through commercial channels.

[0064] The preparation and application process of the adsorption-sealing fire extinguishing material of this invention is as follows: Figure 7 As shown.

[0065] The technical solutions provided by the present invention will be described in detail below with reference to the embodiments, but they should not be construed as limiting the scope of protection of the present invention.

[0066] Example 1: Preparation of a pure chemical foaming carrier with zero surfactant addition

[0067] Take 17.5g of waste bottom ash and 17.5g of slag, and mix them evenly at 200r / min for 2min to obtain a mixture. Weigh 2.7131g of NaOH and 21.3541g of water glass and mix them evenly with 3.2328g of water to prepare an alkali activator solution. Pour the alkali activator solution into the above mixture, stir at 400rpm / min for 2 minutes, let stand, and cure at room temperature for 2 days to obtain a pure chemical foaming carrier with zero surfactant addition.

[0068] Figure 1 The image shows a magnified micrograph of the internal pore structure of the pure chemical foaming carrier with zero surfactant added, prepared in Example 1. As can be seen from the image, the aluminum contained in the municipal solid waste incineration bottom ash reacts with the alkali in the alkali activator to release hydrogen gas, forming a distinct pore structure inside the slurry.

[0069] Example 2: Preparation of carriers with different substrate ratios and zero surfactant addition

[0070] Take 24.5g of waste bottom ash and 10.5g of slag, and mix them evenly at 200r / min for 2min to obtain a mixture. Weigh 1.7441g of NaOH and 13.7276g of water glass and mix them evenly with 8.3282g of water to prepare an alkali activator solution. Pour the alkali activator solution into the above mixture, stir at 400r / min for 2 minutes, pour it into a mold and let it stand for 2 days to cure at room temperature.

[0071] Figure 2 The foaming ratio diagram of porous carriers prepared in Example 2 with different ratios of waste bottom ash and slag (i.e., based on Example 2, only the mass ratio of waste bottom ash and slag is adjusted, while the other steps and parameters remain unchanged) shows that when the mass ratio of municipal solid waste incineration bottom ash to slag is 5:5, the foaming effect is the best, reaching 132.70%, and the setting time is about 11 minutes and 45 seconds.

[0072] Example 3: Preparation of a physical-chemical composite foaming carrier (porous carrier) with surfactant addition > 0

[0073] Take 17.5g of waste bottom ash and 17.5g of slag, and mix them evenly at 200r / min for 2min to obtain a mixture. Dissolve 11mL of surfactant OB-2 in 89mL of water and prepare foam by stirring with a high-speed stirrer. Weigh 2.7131g of NaOH and 21.3541g of water glass and mix them evenly with 3.2328g of foam to obtain an alkaline foaming liquid. Mix the alkaline foaming liquid and the above mixture and stir at 400r / min for 2 minutes (to obtain a foaming slurry), then let it stand and cure at room temperature for 2 days.

[0074] Figure 3 The image shown is a magnified micrograph of the internal pore structure of the physical-chemical composite foaming carrier prepared in Example 3. It can be seen that the carrier is covered with pores. Compared with chemical foaming without the addition of surfactants, the pore structure of the carrier obtained by the physical-chemical composite foaming method is more developed.

[0075] Figure 4 This demonstrates that, based on Example 3, by keeping the foam addition amount constant and changing the amount of surfactant added during foam preparation, the foaming ratio of the porous carrier can be altered. It is evident that the foaming ratio of the porous carrier increases with increasing surfactant addition. When the surfactant mass fraction in the foaming slurry is between 0.001‰ and 0.01‰, the average foaming ratio of the porous carrier is 1.26-1.32 times. When the added surfactant mass fraction increases from 0.01‰ to 0.03‰, the foaming ratio of the carrier also shows a significant improvement. When the added surfactant mass fraction is between 0.03‰ and 0.1‰, the average foaming ratio increases from 1.64 times to 2.34 times.

[0076] Example 4: Amine loading

[0077] 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 foam is prepared by stirring with a high-speed stirrer.

[0078] The above-mentioned foamed slurry was injected into the goaf of a coal mine by grouting and cured at room temperature for 2 days to form a porous carrier. Tetraethylenepentamine (TEPA) was then sprayed to achieve organic amine loading; the amount of tetraethylenepentamine sprayed was 25 wt% of the mass of the foamed slurry, that is, the amine loading was 25 wt%. A porous carrier loaded with 25 wt% TEPA was obtained, which is an adsorption, sealing and fire extinguishing material.

[0079] like Figure 5The figure shows the CO2-TPD spectrum obtained by chemisorption analyzer for the porous support loaded with 25 wt% TEPA prepared in Example 4 (the surfactant mass fraction in the foaming slurry is 0.07‰). During the test, the chemisorption analyzer first purged the porous support sample with inert helium to remove the impurity gas originally adsorbed, then introduced CO2 to allow the material to adsorb, and finally introduced helium for desorption and recorded the TCD signal. As can be seen from the figure, CO2 desorption can be achieved at 46℃; the desorption peak area is 746371.701, representing an actual desorption amount of 3.106 mmol / g.

[0080] Example 5

[0081] Based on Example 4, only the TEPA spraying amount was adjusted so that the tetraethylenepentamine spraying amount was 0%, 5wt%, 10wt%, 15wt%, and 20wt% of the foaming slurry mass, while all other steps and parameters remained unchanged. The CO2 desorption amount of the porous carrier loaded with TEPA was statistically analyzed (testing method was the same as in Example 4), and the results are as follows: Figure 6 As shown

[0082] Figure 6 The graph shows the CO2 desorption amounts of porous carriers loaded with different amounts of TEPA in Examples 4 and 5. As can be seen from the graph, the CO2 desorption amount increased significantly after loading with amine, indicating that the introduction of amine significantly increased the CO2 adsorption capacity of the porous carrier. With the increase of amine loading, the CO2 desorption amount of the carrier also increased continuously. When the amine loading reached 25 wt% of the foaming slurry, the CO2 desorption amount of the porous carrier was the highest, at 3.106 mmol / g.

[0083] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. An adsorption-sealing fire-extinguishing material, characterized in that, Including porous supports and organic amines; The method for preparing the porous support includes the following steps: The waste bottom ash and slag are mixed evenly to obtain a mixture; The surfactant is dissolved in water and stirred to produce foam. Then, an alkaline activator is added and mixed well to obtain an alkaline foaming solution. The alkaline foaming liquid is mixed with the mixture to obtain a foaming slurry; The foaming slurry is cured 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; The mass ratio of the waste bottom ash to the slag is 9:1-1:9; The surfactant is AEC-9Na or OB-2; the mass fraction of the surfactant in the foaming slurry is 0.001‰-0.1‰; The mass ratio of the alkaline foaming liquid to the mixture is (3-5):

5.

2. The adsorption-sealing fire-extinguishing material according to claim 1, characterized in that, The mass fraction of alkali activator in the foaming slurry is 20%-40%.

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

2.

4. The adsorption-sealing fire-extinguishing material according to claim 1, characterized in that, The curing process specifically involves standing at room temperature for 2 days.

5. The application of the adsorption-sealing fire extinguishing material as described in any one of claims 1-4 in the goaf of an underground coal mine.

6. The application according to claim 5, characterized in that, The foaming slurry described in claim 1 is injected into the goaf area of ​​a coal mine and cured at room temperature for 2 days to obtain a porous carrier; organic amine is sprayed onto the porous carrier to achieve sealing and fire prevention in the goaf area of ​​the coal mine.

7. The application of the adsorption-blocking fire extinguishing material as described in any one of claims 1-4 in carbon dioxide adsorption-desorption.

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