A method of spraying thin layers of material in mining using supercritical carbon dioxide

Abstract

The application discloses a kind of mining methods for spraying thin layer material using supercritical carbon dioxide, and relates to the technical field of mining spraying material.The method comprises the following steps: preparing solid-phase material and placing it in an explosion-proof mixer, preparing liquid-phase material, and placing the liquid-phase material in a liquid-phase material storage tank; the explosion-proof mixer is heated and kept stirring; carbon dioxide storage tank provides gaseous carbon dioxide, and the gaseous carbon dioxide is converted into supercritical carbon dioxide by temperature control and pressurization; the liquid-phase material is input into the explosion-proof mixer, and in the explosion-proof mixer, the liquid-phase material and the solid-phase material are fully stirred and mixed in the environment of supercritical carbon dioxide to prepare a mining thin spraying material slurry; the mining thin spraying material slurry in the explosion-proof mixer is sprayed out through a spray gun.The preparation method is simple, improves the dispersibility of polymers, improves the performance of the mining thin spraying material, realizes the fixation of carbon dioxide, and also recovers carbon dioxide.

Description

Technical Field

[0001] This invention relates to the field of mining spraying materials technology, specifically to a method for spraying thin-layer materials using supercritical carbon dioxide in mining applications. Background Technology

[0002] Due to its low toxicity, volatility, and environmental friendliness, supercritical carbon dioxide technology has been widely used in fields such as chemical engineering, pharmaceuticals, and materials science.

[0003] Mining thin-layer sprayed materials generally refer to special materials used in mine support and engineering construction for gas control, fire prevention, dust control, and reinforcement of roadways and slopes. These materials are typically sprayed onto the surfaces of mine roadways and slopes to improve their stability and reduce coal dust, provide fire protection, and offer support. These materials are characterized by strong adhesion, wear resistance, and impact resistance, enabling them to meet the specific support requirements of the mining environment. However, the performance of mining thin-layer sprayed materials is inextricably linked to the uniformity of polymer dispersion, and current technologies still suffer from the technical problem of uneven polymer dispersion.

[0004] This shows that the existing technology needs further improvement. Summary of the Invention

[0005] The purpose of this invention is to provide a method for spraying thin-layer materials for mining using supercritical carbon dioxide. Because supercritical carbon dioxide has gas and liquid phase properties, it has high diffusivity and permeability. By making full use of its properties, the dispersion of polymers can be promoted, and better performance mining thin-layer spray materials can be prepared. The equipment can be used directly underground, and the prepared mining thin-layer spray materials can be directly sprayed onto the required roadways and slopes. Gas recovery can also be achieved, allowing carbon dioxide to be reused.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] A method for spraying a thin-film material using supercritical carbon dioxide in mining applications includes the following steps:

[0008] Step 1: Prepare the necessary equipment

[0009] The device includes an explosion-proof mixer, the input end of which is connected to a carbon dioxide storage tank and a liquid material storage tank, and the output end of which is connected to a spray gun.

[0010] Step 2: Prepare solid materials and place them in the explosion-proof mixer. The solid materials include cement and light calcium carbonate. Mix and stir the solid materials in the explosion-proof mixer thoroughly to make them evenly mixed.

[0011] Prepare a liquid material, which includes a polymer, an additive, and water, and place the liquid material in a liquid material storage tank.

[0012] Step 3: Heat the explosion-proof mixer while maintaining stirring;

[0013] Step 4: Provide gaseous carbon dioxide through a carbon dioxide storage tank, and convert the gaseous carbon dioxide into supercritical carbon dioxide located in an explosion-proof mixer by temperature and pressure control.

[0014] Step 5: Input the liquid phase material into the explosion-proof mixer. Inside the explosion-proof mixer, the liquid phase material and the solid phase material are thoroughly stirred and mixed in a supercritical carbon dioxide environment to prepare a slurry of thin-spray material for mining.

[0015] Step 6: The slurry of mining thin-film material in the explosion-proof mixer is sprayed out through the spray gun.

[0016] In the above-mentioned method for applying thin-layer materials using supercritical carbon dioxide in mining, in step one, a carbon dioxide explosion-proof delivery booster pump is connected between the carbon dioxide storage tank and the explosion-proof mixer, and a liquid phase material explosion-proof delivery booster pump is connected between the liquid phase material storage tank and the explosion-proof mixer; a thin-layer spray material explosion-proof delivery pump is connected between the explosion-proof mixer and the spray gun.

[0017] In the above-mentioned method for spraying thin-layer materials using supercritical carbon dioxide in mining, in step one, the explosion-proof mixer includes an explosion-proof tank body, an auger is installed inside the explosion-proof tank body, and an explosion-proof motor is installed on the outer wall of the explosion-proof tank body. The explosion-proof motor drives the auger to rotate. An explosion-proof mixer exhaust port, an explosion-proof mixer pressure relief valve, a heater, a pressure gauge, and a temperature gauge are connected to the outside of the explosion-proof tank body.

[0018] In the above-mentioned method for spraying thin-layer materials using supercritical carbon dioxide in mining, in step two, the polymer is a powder or liquid, and the additives include water-reducing agents, film-forming agents, defoamers, and cellulose.

[0019] In the above-mentioned method for spraying thin-layer materials using supercritical carbon dioxide in mining, the temperature in step four is 32-50℃ and the pressure is 7.4-20MPa.

[0020] The above-mentioned method for spraying a thin-layer material using supercritical carbon dioxide in mining applications, wherein the polymer is a resin liquid, and by weight, the polymer is 50-70 parts, the additive is 5-10 parts, and the water is 20-40 parts.

[0021] In the above-mentioned method for spraying thin-layer materials using supercritical carbon dioxide in mining applications, the weight ratio of water-reducing agent, film-forming agent, defoamer, and cellulose in the additives is 1-2:2-3:4-6:1-2.

[0022] The above-mentioned method for spraying thin-layer materials using supercritical carbon dioxide in mining applications includes a water-reducing agent that is a polycarboxylate water-reducing agent, a film-forming agent that is a polyurethane resin, an antifoaming agent that is an organosilicon antifoaming agent, and a cellulose that is lignocellulose.

[0023] Compared with the prior art, the present invention brings the following beneficial technical effects:

[0024] (1) The mining thin-spray material prepared by this invention utilizes supercritical carbon dioxide. Because supercritical carbon dioxide possesses both gaseous and liquid phase properties, it exhibits high solubility under supercritical conditions, allowing it to rapidly penetrate into the polymer system and uniformly disperse the polymer molecules within it. Furthermore, supercritical carbon dioxide possesses both the solubility of a liquid state and the diffusivity of a gaseous state; this dual characteristic further promotes polymer dispersion. Therefore, the polymer dispersion is more uniform, resulting in better adhesion and sealing properties.

[0025] (2) The present invention utilizes a method of spraying thin-layer materials with supercritical carbon dioxide, which can expand the utilization of carbon dioxide resources.

[0026] (3) The device involved in the method of supercritical carbon dioxide spraying thin-layer material of the present invention is suitable for underground use. It can directly spray the mixed mining thin-layer spray material onto the roadway and slope through an explosion-proof conveying pump and spray gun.

[0027] In summary, the method of the present invention is simple to operate, improves the dispersibility of polymers, enhances the performance of mining thin-spray materials, achieves carbon dioxide fixation, and can also recover carbon dioxide for reuse. Furthermore, the device for preparing mining thin-spray materials using supercritical carbon dioxide can be used underground, and the prepared mining thin-spray materials can be directly sprayed onto coal mine roadways and slopes to reduce coal dust, prevent fires, and provide support. Attached Figure Description

[0028] The present invention will be further described below with reference to the accompanying drawings:

[0029] Figure 1 This is a flowchart of the method for spraying thin-layer materials using supercritical carbon dioxide according to the present invention;

[0030] Figure 2 This is a schematic diagram of the device structure required for the present invention;

[0031] Figure 3 This is a schematic diagram of the explosion-proof mixer structure of the present invention;

[0032] In the picture:

[0033] 1-Carbon dioxide storage tank; 2-Carbon dioxide explosion-proof conveying and booster pump; 3-Explosion-proof mixer; 4-Liquid material storage tank; 5-Liquid material explosion-proof conveying and booster pump; 6-Explosion-proof gas recovery device; 7-Thin spray material explosion-proof conveying pump; 8-Spray gun; 9-Carbon dioxide storage tank outlet; 10-Carbon dioxide storage tank valve; 11-Carbon dioxide explosion-proof conveying and booster pump inlet; 12-Carbon dioxide explosion-proof conveying and booster pump outlet; 13-Liquid material storage tank outlet; 14-Liquid material storage tank valve; 15-Liquid material explosion-proof conveying and booster pump inlet; 16-Liquid material explosion-proof conveying and booster pump 17 - Explosion-proof gas recovery unit inlet; 18 - Explosion-proof mixer outlet valve; 19 - Thin spray material explosion-proof conveying pump inlet; 20 - Thin spray material explosion-proof conveying pump outlet; 21 - Explosion-proof mixer liquid phase material inlet; 22 - Explosion-proof mixer carbon dioxide inlet; 23 - Explosion-proof motor; 24 - Auger; 25 - Explosion-proof mixer outlet; 26 - Explosion-proof mixer exhaust port; 27 - Explosion-proof mixer pressure relief valve; 28 - Heater; 29 - Pressure gauge; 30 - Thermometer; 31 - Carbon dioxide explosion-proof conveying booster pump outlet valve; 32 - Liquid phase material explosion-proof conveying booster pump outlet valve. Detailed Implementation

[0034] This invention proposes a method for spraying thin-layer materials using supercritical carbon dioxide in mining. To make the advantages and technical solutions of this invention clearer and more explicit, the invention will be further described below with reference to specific embodiments.

[0035] It is understood that the connection relationships described in this application refer to direct or indirect connections. For example, the connection between A and B can be a direct connection between A and B, or an indirect connection between A and B through one or more other electrical components. For example, A can be directly connected to C, and C can be directly connected to B, thus achieving a connection between A and B through C. It is also understood that the "A connects to B" described in this application can be a direct connection between A and B, or an indirect connection between A and B through one or more other electrical components.

[0036] The technical solution of this application will be further described in detail below with reference to the accompanying drawings.

[0037] Combination Figure 2 and Figure 3As shown, the apparatus required for a method of spraying thin-layer materials using supercritical carbon dioxide for mining applications according to the present invention includes a carbon dioxide storage tank 1, an explosion-proof mixer 3, a liquid material storage tank 4, and a spray gun 8. The carbon dioxide storage tank 1 stores carbon dioxide. An explosion-proof carbon dioxide delivery booster pump 2 is provided between the carbon dioxide storage tank 1 and the explosion-proof mixer 3. The carbon dioxide storage tank 1 is provided with a carbon dioxide storage tank outlet 9 and a carbon dioxide storage tank valve 10. The explosion-proof carbon dioxide delivery booster pump 2 is provided with a carbon dioxide explosion-proof delivery booster pump inlet 11 and a carbon dioxide explosion-proof delivery booster pump outlet 12. An explosion-proof carbon dioxide delivery booster pump outlet valve 31 is provided between the explosion-proof carbon dioxide delivery booster pump 2 and the explosion-proof mixer 3.

[0038] A liquid material explosion-proof conveying booster pump 5 is installed between the liquid material storage tank 4 and the explosion-proof mixer 3. The liquid material explosion-proof conveying booster pump 5 is equipped with a liquid material explosion-proof conveying booster pump inlet 15 and a liquid material explosion-proof conveying booster pump outlet 16. The liquid material storage tank 4 is equipped with a liquid material storage tank outlet 13. A liquid material storage tank valve 14 is installed between the liquid material storage tank 4 and the liquid material explosion-proof conveying booster pump 5.

[0039] The explosion-proof mixer 3 is connected to the explosion-proof gas recovery device 6, and the explosion-proof gas recovery device 6 is provided with an explosion-proof gas recovery device inlet 17.

[0040] The explosion-proof mixer 3 is connected to the spray gun 8 via the explosion-proof conveying pump 7 for thin spraying material. The explosion-proof conveying pump 7 for thin spraying material is equipped with an inlet 19 and an outlet 20. An explosion-proof mixer outlet valve 18 is installed on the pipeline connecting the explosion-proof conveying pump 7 and the explosion-proof mixer 3.

[0041] Specifically, such as Figure 3 As shown, the specific structure of the explosion-proof mixer 3 includes an explosion-proof tank body, an auger 24 installed inside the tank body, and an explosion-proof motor 23 installed on the outer wall of the tank body. The auger is driven to rotate by the explosion-proof motor. An explosion-proof mixer exhaust port 26, an explosion-proof mixer pressure relief valve 27, a heater 28, a pressure gauge 29, and a temperature gauge 30 are connected to the outside of the explosion-proof tank body. The explosion-proof tank body also has an explosion-proof mixer liquid phase material inlet 21, an explosion-proof mixer carbon dioxide inlet 22, and an explosion-proof mixer outlet 25.

[0042] Using the above-mentioned device, combined with Figure 1 This invention provides a detailed description of a method for spraying a thin-film material using supercritical carbon dioxide for mining applications, specifically including the following steps:

[0043] Step 1: Prepare solid materials and place them in an explosion-proof mixer. The solid materials include cement and light calcium carbonate. Mix and stir the solid materials in the explosion-proof mixer thoroughly to ensure that the two are evenly mixed.

[0044] Prepare the liquid phase material, which includes polymer, additives and water. After mixing the liquid phase material evenly, place it in the liquid phase material storage tank.

[0045] The aforementioned polymer, whether in powder or liquid form, specifically a resin solution, comprises 50-70 parts by weight of polymer, 5-10 parts by weight of additives, and 20-40 parts by weight of water. Additives include water-reducing agents, film-forming agents, defoamers, and cellulose.

[0046] In the admixtures, the weight ratio of water-reducing agent, film-forming agent, defoamer, and cellulose is 1-2:2-3:4-6:1-2.

[0047] More specifically, the water-reducing agent is a polycarboxylate water-reducing agent, the film-forming agent is a polyurethane resin, the defoamer is an organosilicon defoamer, and the cellulose is lignocellulose.

[0048] Step 2: Heat the explosion-proof mixer while maintaining stirring;

[0049] Step 3: Provide gaseous carbon dioxide through a carbon dioxide storage tank, and then introduce the carbon dioxide into an explosion-proof mixer. The gaseous carbon dioxide is converted into supercritical carbon dioxide by temperature and pressure control; the temperature is 32-50℃ and the pressure is 7.4-20MPa.

[0050] Step 4: Input the liquid phase material into the explosion-proof mixer. Inside the explosion-proof mixer, the liquid phase material and the solid phase material are thoroughly stirred and mixed in the supercritical carbon dioxide environment to prepare a slurry of thin-spray material for mining. Supercritical carbon dioxide has both the solubility in the liquid state and the diffusivity in the gaseous state. This dual characteristic can further promote the dispersion of the polymer.

[0051] Step 5: The slurry of the mining thin-film material in the explosion-proof mixer is sprayed out through the spray gun.

[0052] The present invention will be further described below with reference to specific embodiments.

[0053] Example 1:

[0054] Step 1: Weigh out the solid phase materials: 100 parts each of cement and light calcium carbonate; weigh out the liquid phase materials: 70 parts of polymer, 10 parts of additives, and 20 parts of water. The weight ratio of the additives (water-reducing agent, film-forming agent, defoamer, and cellulose) is 1:3:4:2. Place the prepared solid phase materials in an explosion-proof mixer, mix thoroughly, and stir. Place the liquid phase materials in a polymer storage tank.

[0055] Step 2: Start the explosion-proof mixer and heat it;

[0056] Step 3: Open the valve of the carbon dioxide storage tank and the outlet valve of the carbon dioxide explosion-proof delivery booster pump. Use the carbon dioxide explosion-proof delivery booster pump to charge carbon dioxide into the explosion-proof mixer, increasing the pressure inside the explosion-proof mixer and causing the gaseous carbon dioxide to become supercritical.

[0057] Step 4: Open the valve of the liquid material storage tank and the discharge valve 32 of the liquid material explosion-proof conveying booster pump. The liquid material is injected into the explosion-proof mixer through the liquid material explosion-proof conveying booster pump. The solid material, liquid material and supercritical carbon dioxide in the explosion-proof mixer are fully mixed and stirred by the explosion-proof motor and auger to form a slurry of thin spray material for mining.

[0058] Step 5: Close the valves of the liquid material storage tank, the discharge valve of the liquid material explosion-proof conveying booster pump, the carbon dioxide storage tank, and the gas outlet valve of the carbon dioxide explosion-proof conveying booster pump in sequence to stop the injection of carbon dioxide and polymer.

[0059] Step 6: Open the pressure relief valve of the explosion-proof mixer to complete the pressure relief inside the explosion-proof mixer, and recover the discharged carbon dioxide through the explosion-proof gas recovery device.

[0060] Step 7: After depressurization is completed, close the pressure relief valve of the explosion-proof mixer, open the discharge valve of the explosion-proof mixer, and use the auger to transport the mixed mining thin-spray material to the thin-spray material explosion-proof conveying pump. Use the thin-spray material explosion-proof conveying pump and spray gun to spray the thin-spray material to the required location.

[0061] The explosion-proof mixer mentioned in this invention is a high-temperature and high-pressure explosion-proof mixer.

[0062] Any parts not mentioned in this invention can be achieved by referring to existing technologies.

[0063] Those skilled in the art should recognize that the above embodiments are only used to illustrate this application and are not intended to limit this application. Any appropriate changes and variations made to the above embodiments within the essential spirit and scope of this application fall within the scope of protection claimed in this application.

Claims

1. A method for spraying thin-layer materials using supercritical carbon dioxide in mining applications, characterized in that, Includes the following steps: Step 1: Prepare the necessary equipment; The device includes an explosion-proof mixer, the input end of which is connected to a carbon dioxide storage tank and a liquid material storage tank, and the output end of which is connected to a spray gun. Step 2: Prepare solid materials and place them in the explosion-proof mixer. The solid materials include cement and light calcium carbonate. Mix and stir the solid materials in the explosion-proof mixer thoroughly to make them evenly mixed. Prepare a liquid material, which includes a polymer, an additive, and water, and place the liquid material in a liquid material storage tank. Step 3: Heat the explosion-proof mixer while maintaining stirring; Step 4: Provide gaseous carbon dioxide through a carbon dioxide storage tank, and convert the gaseous carbon dioxide into supercritical carbon dioxide located in an explosion-proof mixer by temperature and pressure control. Step 5: Input the liquid phase material into the explosion-proof mixer. Inside the explosion-proof mixer, the liquid phase material and the solid phase material are thoroughly stirred and mixed in a supercritical carbon dioxide environment to prepare a slurry of thin-spray material for mining. Step 6: The slurry of mining thin-film material in the explosion-proof mixer is sprayed out through the spray gun; The admixtures include water-reducing agents, film-forming agents, defoamers, and cellulose; the polymer is a resin liquid, and by weight, the polymer is 50-70 parts, the admixtures are 5-10 parts, and the water is 20-40 parts. In step one, a carbon dioxide explosion-proof delivery booster pump is connected between the carbon dioxide storage tank and the explosion-proof mixer, and a liquid phase material explosion-proof delivery booster pump is connected between the liquid phase material storage tank and the explosion-proof mixer; a thin spray material explosion-proof delivery pump is connected between the explosion-proof mixer and the spray gun. In step one, the explosion-proof mixer includes an explosion-proof tank, an auger is installed inside the explosion-proof tank, and an explosion-proof motor is installed on the outer wall of the explosion-proof tank. The explosion-proof motor drives the auger to rotate. An explosion-proof mixer exhaust port, an explosion-proof mixer pressure relief valve, a heater, a pressure gauge, and a temperature gauge are connected to the outside of the explosion-proof tank. In step four, the temperature is 32–50℃ and the pressure is 7.4–20 MPa; In the aforementioned admixtures, the weight ratio of water-reducing agent, film-forming agent, defoamer, and cellulose is 1-2:2-3:4-6:1-2; The water-reducing agent is a polycarboxylate water-reducing agent, the film-forming agent is a polyurethane resin, the defoamer is an organosilicon defoamer, and the cellulose is lignocellulose.

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