A direct CO2 air capture device based on microwave heating

Abstract

This invention discloses a direct CO2 air capture device based on microwave heating. The device includes an inlet pipe, an outlet pipe, a CO2 capture tower, a microwave heating integrated device, a carbon dioxide storage tank, a water tank, various valves, a pump, and a sensor control device. During operation, the air pump introduces air into the CO2 capture tower, where the CO2 is adsorbed by a moisture-curing capture material. After adsorption, water is poured into the capture tower from the water tank to moisten the material. A vacuum pump then creates a vacuum in the water tank, causing the water to flow back into the capture tower, thus maintaining a vacuum state. Subsequently, the microwave heating integrated device is activated, using microwave vibration to rapidly heat the moistened capture material, achieving efficient CO2 desorption. This invention solves the problems of slow desorption speed and low efficiency in traditional moisture-curing capture technology by using microwave heating, and combines this with a vacuum environment to ensure the purity of the desorbed CO2, thereby improving capture efficiency.

Description

Technical Field

[0001] This utility model relates to the field of CO2 variable humidity capture technology, specifically to a CO2 direct air capture device based on microwave heating. Background Technology

[0002] In the face of the pressing situation of addressing climate change, Direct Air Capture (DAC) technology, as a key strategy for achieving carbon neutrality, is receiving widespread attention globally. This technology aims to directly remove carbon dioxide from the atmosphere, which is of great significance for mitigating the greenhouse effect and reducing atmospheric carbon dioxide concentration.

[0003] Moisture Swing Capture, as an important component of the DAC (Modular Carbon Dioxide) technology system, has a unique operating mechanism. Its principle is that under dry conditions, basic groups (such as CO32-) on the surface of the adsorbent... 2- The adsorbent adsorbs CO2 from the air; however, under conditions of high humidity or high hydration, the adsorbed CO2 gradually desorbs. However, in practical applications, the desorption process driven by high humidity is very slow, resulting in a low desorption rate. Furthermore, the CO2 produced during desorption in a closed environment inhibits further desorption reactions, making it difficult to efficiently desorb CO2 at room temperature; the desorption is incomplete and the CO2 yield is low. Summary of the Invention

[0004] In order to solve the problems existing in the prior art, the purpose of this utility model is to provide a direct CO2 air capture device based on microwave heating, so as to solve the problems of low desorption rate and incomplete desorption in CO2 wet capture technology.

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

[0006] A direct CO2 air capture device based on microwave heating includes an inlet pipe 1, an adsorption inlet valve 1-1, a desorption water inlet valve 1-2, a capture tower inlet valve 1-3, an outlet pipe 2, an air pump inlet valve 2-1, a desorption water return valve 2-2, a capture tower outlet valve 2-3, an air pump 2-4, an air pump outlet valve 2-5, a first microwave heating integrated device 3, a first waveguide valve 3-1, a second microwave heating integrated device 4, a second waveguide valve 4-1, a CO2 capture tower 5, a microwave absorbing material 6, a CO2 humidification capture material 7, a carbon dioxide storage tank 8, a storage tank inlet valve 8-1, a compressor 8-2, a water tank 9, a water tank vent valve 9-1, a water tank vacuum valve 9-2, a water pump 9-3, a vacuum pump 9-4, a liquid level monitor 10, a temperature and humidity detector 11, a microwave alarm sensor 13, and an integrated central control device 14.

[0007] The air inlet pipe 1 is connected to the upper end of the CO2 collection tower 5 through the air inlet valve 1-3 of the collection tower; the CO2 collection tower 5 is wrapped with microwave absorbing material 6, the first microwave heating integrated device 3 and the second microwave heating integrated device 4 are arranged on both sides of the CO2 collection tower 5, and are respectively connected to the CO2 collection tower 5 by the first waveguide valve 3-1 and the second waveguide valve 4-1, and the liquid level monitor 10 is arranged on the side of the CO2 collection tower 5;

[0008] The outlet pipe 2 is connected to the lower end of the CO2 capture tower 5 through the capture tower outlet valve 2-3. The air pump 2-4 draws air into the CO2 capture tower 5 through the adsorption inlet valve 1-1, the inlet pipe 1, and the capture tower inlet valve 1-3 to adsorb the CO2 wet capture material 7 loaded in the tower, and then releases the air into the outside air through the capture tower outlet valve 2-3, the air pump inlet valve 2-1, and the air pump outlet valve 2-5. The carbon dioxide storage tank 8 is connected in series with the compressor 8-2 through the storage tank inlet valve 8-1 and is connected to the CO2 capture tower 5 through the outlet pipe 2.

[0009] The water tank 9 is connected to the CO2 collection tower 5 via a water pump 9-3, a desorption water inlet valve 1-2, and an air inlet pipe 1. The upper side of the water tank 9 is provided with a water tank vent valve 9-1 and a water tank vacuum valve 9-2 connected to a vacuum pump 9-4. The desorption water return valve 2-2 connects the air outlet pipe 2 to the water tank 9.

[0010] The temperature and humidity detector 11 is located on the side and above the CO2 humidity trapping tower 5; the microwave alarm sensor 13 is located on the outside of the overall device; the integrated central control device 14 receives data signals from the liquid level monitor 10 and the temperature and humidity detector 11, and controls all valves, pumps and microwave heating integrated devices in this device.

[0011] The first microwave heating integrated device 3 and the second microwave heating integrated device 4 are respectively connected to the interior of the CO2 capture tower 5 through the first waveguide valve 3-1 and the second waveguide valve 4-1. By using the principle of microwave vibration of water molecules transmitted through the waveguide, the CO2 in the tower is quickly and fully desorbed from the wet capture material 7.

[0012] The first microwave heating integrated device 3 and the second microwave heating integrated device 4 are multi-feed microwave heating devices. The first microwave heating integrated device 3 is a microwave heating device with a frequency of 2.45 GHz, and the microwave heating integrated device 4 is a microwave heating device with a frequency of 915 MHz. The microwave heating devices with different frequencies work simultaneously during the desorption process to form a multi-feed microwave heating integrated device.

[0013] The microwave absorbing material 6 is wrapped around the outside of the CO2 capture tower 5. The material can be a dielectric material such as ceramic or silicon carbide, or a carbon fiber or nanocomposite material. While preventing microwave leakage due to accidents, it also provides some insulation, which is beneficial for CO2 desorption.

[0014] Water in the water tank 9 is drawn by the water pump 9-3 and injected into the CO2 capture tower 5 through the desorption water inlet valve 1-2, fully wetting the CO2 wet capture material 7.

[0015] After the vacuum pump 9-4 fills the collection tower with water to fully wet the CO2-wetted collection material 7, it evacuates the water tank 9 to a vacuum state, so that the water in the CO2 collection tower 5 flows into the water tank 9 spontaneously by gravity, causing the CO2 collection tower 5 to become a vacuum state, so as to ensure that the desorbed CO2 is not mixed with air.

[0016] Compared with the prior art, the beneficial effects of this utility model are:

[0017] 1. Significantly improves desorption efficiency and rate. Existing variable humidity capture technology relies on high humidity to drive desorption, which is slow and difficult to achieve complete desorption. This invention utilizes a multi-feed microwave heating integrated device (working in tandem with 2.45GHz and 915MHz frequencies) to rapidly heat the wetted capture material by leveraging the properties of microwave vibration of water molecules, significantly accelerating the CO2 desorption process. This solves the core problems of low desorption rate and incomplete desorption in traditional technologies, significantly shortens the desorption cycle, and increases CO2 production per unit time.

[0018] 2. Ensuring high purity of desorbed CO2. In existing technologies, the purity of CO2 is easily reduced due to the intrusion of ambient air during the desorption process. This invention uses a vacuum pump to create a vacuum in the water tank, causing water to flow back into the collection tower and forming a vacuum environment. Combined with the sealed design of the desorption stage, air intrusion is effectively avoided, ensuring the purity of the desorbed CO2 and providing a high-quality gas source for subsequent storage, transportation, and resource utilization (such as industrial raw materials, carbon sequestration, etc.).

[0019] 3. Optimize energy consumption and heating uniformity. Traditional heating methods suffer from high energy consumption and uneven heating. This invention employs dual-frequency microwave synergistic heating, where microwaves of different frequencies act more evenly on the capturing material, improving heating efficiency. Simultaneously, microwave heating directly acts on water molecules, resulting in higher energy conversion efficiency than traditional heat conduction methods, reducing the energy cost per unit of CO2 desorption, and better meeting energy conservation and environmental protection requirements.

[0020] 4. Enhance the safety and stability of the device. By wrapping the outside of the CO2 capture tower with microwave-absorbing material, microwave leakage can be effectively prevented. In conjunction with the microwave alarm sensor, this can prevent microwaves from causing harm to the environment and operators. On the other hand, the microwave-absorbing material also has a heat-insulating effect, reducing heat loss during the desorption process and helping to maintain a stable temperature inside the tower. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the structure of the device of this utility model. Detailed Implementation

[0022] The specific embodiments of this utility model will be described in further detail below with reference to the accompanying drawings and examples. The following examples are used to illustrate this utility model, but are not intended to limit its scope.

[0023] like Figure 1 As shown, this utility model provides a direct CO2 air capture device based on microwave heating, including an inlet pipe 1, an adsorption inlet valve 1-1, a desorption water inlet valve 1-2, a capture tower inlet valve 1-3, an outlet pipe 2, an air pump inlet valve 2-1, a desorption water return valve 2-2, a capture tower outlet valve 2-3, an air pump 2-4, an air pump outlet valve 2-5, a first microwave heating integrated device 3, a first waveguide valve 3-1, a second microwave heating integrated device 4, a second waveguide valve 4-1, a CO2 capture tower 5, a microwave absorbing material 6, a CO2 humidification capture material 7, a carbon dioxide storage tank 8, a storage tank inlet valve 8-1, a compressor 8-2, a water tank 9, a water tank vent valve 9-1, a water tank vacuum valve 9-2, a water pump 9-3, a vacuum pump 9-4, a liquid level monitor 10, a temperature and humidity detector 11, a support frame 12, a microwave alarm sensor 13, and an integrated central control device 14.

[0024] The air inlet pipe 1 is connected to the upper end of the CO2 collection tower 5 through the collection tower inlet valve 1-3; the CO2 collection tower 5 is wrapped with microwave absorbing material 6, the first microwave heating integrated device 3 and the second microwave heating integrated device 4 are arranged on both sides of the CO2 collection tower 5, and are respectively connected to the CO2 collection tower 5 by the first waveguide valve 3-1 and the second waveguide valve 4-1; the liquid level monitor 10 is arranged on the side of the CO2 collection tower 5; the support frame 12 is used to fix the CO2 collection tower 5.

[0025] The outlet pipe 2 is connected to the lower end of the CO2 capture tower 5 through the capture tower outlet valve 2-3. The air pump 2-4 draws air into the CO2 capture tower 5 through the adsorption inlet valve 1-1, the inlet pipe 1, and the capture tower inlet valve 1-3 to adsorb the CO2 wet capture material 7 loaded in the tower, and then releases the air into the outside air through the capture tower outlet valve 2-3, the air pump inlet valve 2-1, and the air pump outlet valve 2-5. The carbon dioxide storage tank 8 is connected in series with the compressor 8-2 through the storage tank inlet valve 8-1 and is connected to the CO2 capture tower 5 through the outlet pipe 2.

[0026] The water tank 9 is connected to the CO2 collection tower 5 via a water pump 9-3, a desorption water inlet valve 1-2, and an air inlet pipe 1. The upper side of the water tank 9 is equipped with a water tank vent valve 9-1 and a water tank vacuum valve 9-2 connected to a vacuum pump 9-4. The desorption water return valve 2-2 connects the air outlet pipe 2 to the water tank 9.

[0027] The temperature and humidity detector 11 is located on the side and above the CO2 humidity capture tower 5; the microwave alarm sensor 13 is located on the outside of the overall device; the integrated central control device 14 receives data signals from the liquid level monitor 10, temperature and humidity detector 11 and other sensors, and controls all valves, pumps and microwave heating integrated devices in this device.

[0028] In a preferred embodiment of the present invention, the first microwave heating integrated device 3 and the second microwave heating integrated device 4 are respectively connected to the interior of the CO2 capture tower 5 through the first waveguide valve 3-1 and the second waveguide valve 4-1. By utilizing the principle of microwave vibration of water molecules transmitted through the waveguide, the CO2 in the tower is quickly and fully desorbed from the wetted CO2 capture material 7.

[0029] In a preferred embodiment of this utility model, the first microwave heating integrated device 3 and the second microwave heating integrated device 4 are multi-feed microwave heating devices. The first microwave heating integrated device 3 is a microwave heating device with a frequency of 2.45 GHz, and the microwave heating integrated device 4 is a microwave heating device with a frequency of 915 MHz. The microwave heating devices of different frequencies work simultaneously during the desorption process to form a multi-feed microwave heating integrated device.

[0030] In a preferred embodiment of this invention, the microwave absorbing material 6 is wrapped around the outside of the CO2 trapping tower 5. The material can be a dielectric material such as ceramic or silicon carbide, or a carbon fiber or nanocomposite material. While preventing microwave leakage due to accidents, it also provides some insulation, which is beneficial for CO2 desorption.

[0031] In a preferred embodiment of the present invention, water in the water tank 9 is drawn by the water pump 9-3 and injected into the CO2 capture tower 5 through the desorption water inlet valve 1-2, fully wetting the CO2 wet capture material 7.

[0032] In a preferred embodiment of this utility model, after the vacuum pump 9-4 fills the CO2 collection tower with water to fully wet the CO2 wet collection material 7, it pumps the water tank 9 to a vacuum state, so that the water in the CO2 collection tower 5 flows into the water tank 9 spontaneously by gravity, thereby changing the CO2 collection tower 5 into a vacuum state to ensure that the desorbed CO2 is not mixed with air.

[0033] like Figure 1 As shown, the working process of this utility model device is as follows: In the initial state, all valves, pumps, and microwave heating integrated devices are closed. During adsorption, the adsorption inlet valve 1-1, the trapping tower inlet valve 1-3, the trapping tower outlet valve 2-3, the air pump inlet valve 2-1, and the air pump outlet valve 2-5 are opened, and the air pump 2-4 is turned on. The device forms a circulating air path with air entering from the top and exiting from the bottom. The temperature and humidity detector 11 monitors the relative humidity of the circulating air path and transmits the information to the integrated central control device 14. If the relative humidity is greater than 80%, the device stops working and closes all valves and air pumps. If the relative humidity is less than or equal to 80%, the above valves and air pumps are kept open. The CO2 humidification trapping material 7 loaded in the CO2 trapping tower 5 adsorbs CO2 in the circulating air. After adsorption is completed, the air pump 2-4 is turned off.

[0034] When wetting the material, keep the adsorption inlet valve 1-1 and the collection tower inlet valve 1-3 open, close the collection tower outlet valve 2-3, the air pump inlet valve 2-1 and the air pump outlet valve 2-5, open the desorption water inlet valve 1-2 and the water tank vent valve 9-1, and turn on the water pump 9-3 to pour the water in the water tank 9 into the CO2 collection tower 5 through the desorption water inlet valve 1-2 and the collection tower inlet valve 1-3. After the liquid level monitor 10 detects that the CO2 collection tower 5 is full of water, turn off the water pump 9-3.

[0035] Before desorption begins, close the adsorption inlet valve 1-1, the desorption water inlet valve 1-2, the collection tower inlet valve 1-3, and the water tank vent valve 9-1. Open the water tank vacuum valve 9-2 and start the vacuum pump 9-4 to evacuate the water tank 9 to a vacuum state. Then close the vacuum pump 9-4 and the water tank vacuum valve 9-2. Open the collection tower outlet valve 2-3 and the desorption return water valve 2-2 to allow the water in the CO2 collection tower 5 to flow into the water tank 9 spontaneously by gravity, while the CO2 collection tower 5 becomes a vacuum state. After the liquid level monitor 10 detects that the water in the CO2 collection tower 5 has been emptied, close the desorption return water valve 2-2 and the collection tower outlet valve 2-3.

[0036] During the microwave desorption stage, the first waveguide valve 3-1 and the second waveguide valve 4-1 are opened, and the first microwave heating integrated device 3 and the second microwave heating integrated device 4 are turned on, making the tower a sealed microwave space. The CO2 humidification capturing material 7 in the CO2 capture tower is rapidly desorbed by the principle of microwave vibration of water molecules. The temperature and humidity detector 11 monitors the temperature in the CO2 capture tower 5 and transmits the information to the integrated central control device 14. If the temperature rises to the range of 80-100℃, the first microwave heating integrated device 3, the second microwave heating integrated device 4, the first waveguide valve 3-1 and the second waveguide valve 4-1 are closed, the capture tower outlet valve 2-3, the air pump inlet valve 2-1 and the storage tank inlet valve 8-1 are opened, and the air pump 2-4 and the compressor 8-2 are turned on to transport and store the CO2 generated by desorption into the carbon dioxide storage tank 8. After the transportation is completed, all valves and pumps are closed.

[0037] The above specific embodiments are only for illustrating the technical concept and features of this utility model. Their purpose is to enable those skilled in the art to implement the technology based on the content of this utility model. It should be noted that all embodiments obtained by those skilled in the art without creative labor, within the principle of this utility model and only by making certain improvements to this utility model, are within the protection scope of this utility model.

Claims

1. A CO2 direct air capture device based on microwave heating, characterized in that, Includes an air inlet pipe (1), an adsorption air inlet valve (1-1), a desorption water inlet valve (1-2), a collection tower air inlet valve (1-3), an air outlet pipe (2), an air pump inlet valve (2-1), a desorption water return valve (2-2), a collection tower air outlet valve (2-3), an air pump (2-4), an air pump outlet valve (2-5), a first microwave heating integrated device (3), a first waveguide valve (3-1), a second microwave heating integrated device (4), and a second waveguide valve. (4-1) CO2 capture tower (5) Microwave absorbing material (6) CO2 humidification capture material (7) Carbon dioxide storage tank (8) Storage tank inlet valve (8-1) Compressor (8-2) Water tank (9) Water tank vent valve (9-1) Water tank vacuum valve (9-2) Water pump (9-3) Vacuum pump (9-4) Liquid level monitor (10) Temperature and humidity detector (11) Microwave alarm sensor (13) Integrated central control device (14) The air inlet pipe (1) is connected to the upper end of the CO2 collection tower (5) through the air inlet valve (1-3) of the collection tower. The CO2 collection tower (5) is wrapped with microwave absorbing material (6). The first microwave heating integrated device (3) and the second microwave heating integrated device (4) are located on both sides of the CO2 collection tower (5) and are connected to the CO2 collection tower (5) by the first waveguide valve (3-1) and the second waveguide valve (4-1) respectively. The liquid level monitor (10) is located on the side of the CO2 collection tower (5). The outlet pipe (2) is connected to the lower end of the CO2 collection tower (5) through the collection tower outlet valve (2-3). The air pump (2-4) draws air into the CO2 collection tower (5) through the adsorption inlet valve (1-1), the inlet pipe (1), and the collection tower inlet valve (1-3) to adsorb the CO2 wet collection material (7) loaded in the tower, and then releases the air into the outside air through the collection tower outlet valve (2-3), the air pump inlet valve (2-1), and the air pump outlet valve (2-5). The carbon dioxide storage tank (8) is connected in series with the compressor (8-2) through the storage tank inlet valve (8-1) and is connected to the CO2 collection tower (5) through the outlet pipe (2). The water tank (9) is connected to the CO2 collection tower (5) via a water pump (9-3), a desorption water inlet valve (1-2) and an air inlet pipe (1). The upper side of the water tank (9) is provided with a water tank vent valve (9-1) and a water tank vacuum valve (9-2) connected to a vacuum pump (9-4). The desorption water return valve (2-2) connects the air outlet pipe (2) to the water tank (9). The temperature and humidity detector (11) is located on the side above the CO2 capture tower (5); the microwave alarm sensor (13) is located on the outside of the overall device; the integrated central control device (14) receives data signals from the liquid level monitor (10) and the temperature and humidity detector (11), and controls all valves, pumps and microwave heating integrated devices in this device.

2. A CO2 direct air capture device based on microwave heating according to claim 1, characterized in that: The first microwave heating integrated device (3) and the second microwave heating integrated device (4) are connected to the interior of the CO2 capture tower (5) through the first waveguide valve (3-1) and the second waveguide valve (4-1), respectively. By using the principle of microwave vibration of water molecules transmitted through the waveguide, the CO2 in the tower is quickly and fully desorbed from the wet capture material (7).

3. A CO2 direct air capture device based on microwave heating according to claim 1, characterized in that: The first microwave heating integrated device (3) is a microwave heating device with a frequency of 2.45 GHz, and the second microwave heating integrated device (4) is a microwave heating device with a frequency of 915 MHz. The microwave heating devices with different frequencies work simultaneously during the desorption process to form a multi-feed microwave heating integrated device.

4. A CO2 direct air capture device based on microwave heating according to claim 1, characterized in that: The absorbing material (6) is wrapped around the outside of the CO2 capture tower (5), and the material is a dielectric material, carbon fiber or nanocomposite material.

5. A CO2 direct air capture device based on microwave heating according to claim 4, characterized in that: The dielectric material is ceramic or silicon carbide.

6. A CO2 direct air capture device based on microwave heating according to claim 1, characterized in that: Water in the water tank (9) is drawn by the water pump (9-3) and injected into the CO2 capture tower (5) through the desorption water inlet valve (1-2) to fully wet the CO2 wet capture material (7).

7. A CO2 direct air capture device based on microwave heating according to claim 1, characterized in that: After the vacuum pump (9-4) fills the CO2 collection tower with water to fully wet the CO2 wet collection material (7), it pumps the water tank (9) to a vacuum state, so that the water in the CO2 collection tower (5) flows into the water tank (9) spontaneously by gravity, so that the CO2 collection tower (5) becomes a vacuum state, ensuring that the desorbed CO2 is not mixed with air.

8. A CO2 direct air capture device based on microwave heating according to claim 1, characterized in that: It also includes a support frame (12) for fixing the CO2 capture tower (5).

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