Radon and temperature and humidity combined elimination control system and method thereof

Abstract

The application provides a radon and temperature and humidity combined elimination control system and a method thereof. The system comprises a supply air section, an exhaust air section and a return air section connected with a radon scattered underground room. In the supply air section, an air inlet of the radon scattered underground room is connected with a supply fan, a mixed air section and a fresh air fan in sequence. In the exhaust air section, an air outlet of the radon scattered underground room is connected with a secondary condenser, an electric heater, a radon continuous adsorption and desorption device, a cooling section of a heat recovery device and an exhaust fan in sequence. In the return air section, a return air outlet of the radon scattered underground room is connected with a return fan, a primary and medium efficiency filter, a primary evaporator, a secondary evaporator, the radon continuous adsorption and desorption device, a primary condenser, a heating section of the heat recovery device and the mixed air section in sequence. The system simultaneously realizes continuous and reliable operation of large air volume adsorption and desorption, can be used for radon elimination in a large space room or a multi-room area, overcomes the deficiencies of conventional radon adsorption devices that cannot continuously eliminate radon in depth and have small air volume, and is beneficial to promotion and application.

Description

Technical Field

[0001] This invention relates to the field of radon gas treatment technology, and in particular to a radon gas and temperature and humidity combined elimination control system and method. Background Technology

[0002] Some underground engineering projects have high radon concentrations within the rock formations, causing radon gas to continuously release into the project. This leads to a buildup and increase in radon concentration within the rooms, potentially exceeding safety limits and causing irreversible harm, including lung cancer. Therefore, continuous radon removal in these rooms is essential. Currently, radon removal in underground projects primarily relies on fresh air replacement. However, improving the replacement effect requires increasing the fresh air supply, leading to significant energy consumption due to deep temperature and humidity control, as well as large ductwork requiring substantial underground space, and higher investment and operating costs. Existing radon removal systems typically use activated carbon adsorption, which also suffers from limitations such as low adsorption airflow (less than 500 m³ / h). 3 Radon has several shortcomings, including its low adsorption capacity ( / h) and difficulty in continuous and effective removal after adsorption saturation.

[0003] In view of this, the present invention is proposed. Summary of the Invention

[0004] The purpose of this invention is to provide a radon gas and temperature and humidity combined elimination control system and method to solve the technical problems existing in the prior art.

[0005] In a first aspect, the present invention provides a radon gas and temperature and humidity combined elimination control system, which includes: an air supply section, an exhaust section and a return air section connected to an underground radon dissipation room;

[0006] In the air supply section, the air inlet of the underground radon-dissipating room is sequentially connected to a supply fan, a mixing section, and a fresh air unit;

[0007] In the exhaust section, the exhaust vent of the underground radon-dissipating room is sequentially connected to a secondary condenser, an electric heater, a radon gas continuous adsorption and desorption device, a cooling section of a heat recovery device, and an exhaust fan;

[0008] In the return air section, the return air vent of the underground radon-dissipating room is sequentially connected to a return air fan, a primary and secondary efficiency filter, a primary evaporator, a secondary evaporator, a radon gas continuous adsorption and desorption device, a primary condenser, a heating section of a heat recovery device, and a mixing section.

[0009] Preferably, the heating section and cooling section of the heat recovery device are connected by a solution pipe and a solution pump to transfer heat from the exhaust air to the return air.

[0010] Preferably, the primary and secondary filters, the first-stage evaporator, the second-stage evaporator, the radon continuous adsorption and desorption device, the first-stage condenser, the heating section of the heat recovery device, the second-stage condenser, the electric heater, the cooling section of the radon continuous adsorption and desorption device and the heat recovery device, and the exhaust fan can be integrated into one unit to form an integrated temperature and humidity control radon removal unit.

[0011] Preferably, the radon continuous adsorption and desorption device has two radon adsorption and desorption modules, one of which is located in the return air channel and the other is located in the exhaust air channel. The two radon adsorption and desorption modules can be moved and interchanged between the return air channel and the exhaust air channel.

[0012] Preferably, the radon adsorption and desorption module uses modified activated carbon. Modified activated carbon has a good adsorption and removal effect on radon, and its adsorption capacity is closely related to air temperature and water vapor content; the lower the temperature and the drier the air, the stronger its adsorption capacity. Lowering the temperature of activated carbon can significantly improve its kinetic adsorption coefficient and enhance its radon adsorption performance. Experimental tests show that at -40℃, the kinetic adsorption coefficient of activated carbon is approximately 162.5 L / g, which is more than 20 times higher than that at room temperature. Creating a continuous and reliable low-temperature and low-humidity environment is crucial for significantly improving radon removal efficiency. Underground projects are buried deep, and the internal room temperature remains stable year-round. However, due to the continuous influx of moisture from the surrounding mountains, the room environment is characterized by humidity and temperature stability. The radon and temperature / humidity combined elimination control system provided by this invention simultaneously achieves continuous and reliable operation of large-volume airflow for adsorption and desorption. It can be used for radon removal in large spaces or multi-room areas, overcoming the shortcomings of conventional radon adsorption devices, such as the inability to continuously remove radon at a deep depth and the small processing volume.

[0013] A second aspect of the present invention provides a method for the combined elimination and control of radon gas and temperature and humidity, comprising the following steps using the aforementioned combined elimination and control system for radon gas and temperature and humidity:

[0014] Outdoor fresh air, after being treated for temperature regulation and filtration, enters the mixing section through the fresh air unit; after being mixed with return air that has undergone radon removal and temperature and humidity treatment, it is sent into the underground radon-dissipating room by the supply fan;

[0015] The return air in the underground radon-dissipating room passes sequentially through the return air fan, primary and secondary filters, primary evaporator, secondary evaporator, radon continuous adsorption and desorption device, primary condenser, and the heating section of the heat recovery device before entering the mixing section. After mixing with the outdoor fresh air, it is sent into the underground radon-dissipating room by the supply fan.

[0016] The exhaust air in the underground radon-dissipating room is successively discharged to the outside through a two-stage condenser, an electric heater, a radon continuous adsorption and desorption device, a cooling section of a heat recovery device, and an exhaust fan.

[0017] Preferably, the outdoor fresh air is filtered and treated to a temperature of 10-30℃ before entering the fresh air unit.

[0018] Preferably, the 20°C return air in the underground radon-dissipating room is first filtered by a primary and medium-efficiency filter, then enters the first-stage evaporator for cooling and dehumidification until the temperature drops to 0°C, and then enters the second-stage evaporator for further deep cooling and dehumidification until it becomes -40°C dry air. After entering the radon continuous adsorption and desorption device, the air at -40°C and after radon removal enters the heating section of the first-stage condenser and heat recovery device. The temperature is heated to 10-30°C and then enters the mixing section, where it is mixed with outdoor fresh air and the temperature is adjusted to 25°C before being sent into the underground radon-dissipating room by the blower.

[0019] Preferably, the exhaust air from the underground radon-emitting room is heated to 40°C by a two-stage condenser and then enters an electric heater. The temperature is then reheated to 120°C before entering a continuous radon adsorption and desorption device. After that, it enters the cooling section of a heat recovery device, where the temperature drops to 50°C before being discharged outdoors.

[0020] Preferably, when the radon gas and temperature and humidity combined elimination control system is running, the automatic control mechanism adjusts the ratio of fresh air to return air by controlling the fresh air fan and return air fan according to the real-time monitoring value of radon concentration in the underground radon-emitting room, thereby accelerating the elimination speed of radon gas in the room.

[0021] Preferably, three radon gas measuring sensors are evenly installed in the outlet of the return air duct. When any one of the radon gas measuring sensors measures radon, it indicates that the radon adsorption in the radon adsorption and desorption module in the return air duct has reached saturation and a radon desorption operation is required.

[0022] The present invention has at least the following beneficial effects:

[0023] This invention utilizes a two-stage compression refrigeration system with two-stage evaporators and condensers to significantly enhance the system's low-temperature processing capabilities, achieving the goal of cooling the air to -40°C while simultaneously greatly improving the removal capacity of water vapor in the air at -40°C. Specifically, the two-stage compression refrigeration system not only creates a low-temperature, low-humidity adsorption environment, significantly enhancing the radon adsorption capacity of modified activated carbon, but also regulates the temperature and humidity of the room air, ensuring the required room temperature and humidity. Furthermore, through a continuous radon adsorption and desorption device, it simultaneously achieves high-volume, continuous, and reliable operation of both adsorption and desorption. This invention can be used for radon removal in large spaces or multi-room areas, overcoming the shortcomings of conventional radon adsorption devices, such as the inability to continuously and deeply remove radon and the small processing volume, demonstrating its advanced nature. Attached Figure Description

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

[0025] Figure 1 This is a schematic diagram of the radon gas and temperature and humidity combined elimination control system provided by the present invention;

[0026] Figure 2 This is a schematic diagram of the radon gas continuous adsorption and desorption device provided by the present invention.

[0027] Explanation of reference numerals in the attached diagram: 1-Underground radon dissipation room; 2-Supply fan; 3-Mixing section; 4-Fresh air fan; 5-Secondary condenser; 6-Electric heater; 7-Continuous radon adsorption and desorption device; 8-Cooling section of heat recovery device; 9-Exhaust fan; 10-Return air fan; 11-Primary and secondary filters; 12-First-stage evaporator; 13-Secondary evaporator; 14-First-stage condenser; 15-Heating section of heat recovery device; 16-Solution pump; 17-Radon gas measuring sensor; 18-Slide rail. Detailed Implementation

[0028] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0029] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting this invention.

[0030] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the stated features. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified. Furthermore, the terms "installed," "connected," and "linked" should be interpreted broadly; for example, they may refer to a fixed connection, a detachable connection, or an integral connection; they may refer to a mechanical connection or an electrical connection; they may refer to a direct connection or an indirect connection through an intermediate medium; and they may refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0031] Example 1

[0032] like Figures 1 to 2 As shown, this embodiment provides a radon gas and temperature / humidity combined elimination control system, including: an air supply section, an exhaust section, and a return air section connected to an underground radon-dissipating room 1; in the air supply section, the air inlet of the underground radon-dissipating room 1 is sequentially connected to a supply fan 2, a mixing section 3, and a fresh air fan 4; in the exhaust section, the exhaust outlet of the underground radon-dissipating room 1 is sequentially connected to a secondary condenser 5, an electric heater 6, a radon gas continuous adsorption and desorption device 7, a cooling section 8 of a heat recovery device, and an exhaust fan 9; in the return air section, the return air outlet of the underground radon-dissipating room 1 is sequentially connected to a return air fan 10, a primary and secondary efficiency filter 11, a primary evaporator 12, a secondary evaporator 13, the radon gas continuous adsorption and desorption device 7, a primary condenser 14, a heating section 15 of a heat recovery device, and a mixing section 3.

[0033] In this embodiment, the heating section 15 and the cooling section 8 of the heat recovery device are connected by a solution pipe and a solution pump 16 to transfer heat from the exhaust air to the return air, thereby increasing the return air temperature and reducing system energy consumption.

[0034] In this embodiment, apart from the fresh air system, the mixing section, and the supply fan, the rest of the system can be integrated into a combined air conditioning unit. The unit can be named an "integrated temperature and humidity control radon removal unit". That is, the primary and secondary filters 11, the first-stage evaporator 12, the second-stage evaporator 13, the radon continuous adsorption and desorption device 7, the first-stage condenser 14, the heating section 15 of the heat recovery device, the second-stage condenser 5, the electric heater 6, the cooling section 8 of the radon continuous adsorption and desorption device 7 and the heat recovery device, and the exhaust fan 9 can be integrated into one unit to form an integrated temperature and humidity control radon removal unit.

[0035] It is worth noting that a radon detection element can also be installed in the underground radon dispersal room 1. This radon detection element is connected to the automatic control mechanism via a signal. Based on the real-time monitoring value of the radon concentration in the underground radon dispersal room 1, the automatic control mechanism controls the fresh air fan 4 and the return air fan 10 to adjust the ratio of fresh and return air, thereby accelerating the elimination of radon in the room and quickly creating a safe air quality environment for the staff in the room, meeting their immediate work needs. Specifically, when the radon concentration in the room is high, the proportion of fresh air is automatically increased to further enhance the radon removal capacity of the acceleration system. Of course, in this embodiment, the automatic control mechanism also establishes a communication connection with the primary evaporator 12, the secondary evaporator 13, the primary condenser 14, the secondary condenser 5, the electric heater 6, and the exhaust fan 9 to achieve feedback control between the various devices.

[0036] In this embodiment, the radon continuous adsorption and desorption device 7 has two radon adsorption and desorption modules. One radon adsorption and desorption module is located in the return air channel, and the other radon adsorption and desorption module is located in the exhaust air channel. The two radon adsorption and desorption modules can be moved and swapped between the return air channel and the exhaust air channel.

[0037] In this embodiment, three radon gas measuring sensors 17 are evenly installed in the outlet of the return air duct. When any one of the radon gas measuring sensors 17 measures radon, it indicates that the radon adsorption in the radon adsorption and desorption module in the return air duct has been saturated and a radon desorption operation is required.

[0038] Specifically, the radon adsorption and desorption modules in the radon continuous adsorption and desorption device 7 can be moved in a staggered manner via the slide rail 18 installed at the bottom. When a module is not radon saturated, it should be located in the return air duct to efficiently adsorb and remove radon from the low-temperature, low-humidity return air. Another module is located in the exhaust air duct, where high-temperature exhaust air continuously desorbs radon from it. When any one of the three radon measuring sensors 17 evenly installed at the outlet of the return air duct detects radon, it indicates that the radon adsorption in this module is saturated and a radon desorption operation is required. This system uses a motor to drive the modules in the return and exhaust air ducts to be swapped. The radon-saturated module is moved to the exhaust air duct, and the desorbed module is moved to the return air duct for the next round of radon adsorption and desorption, thus realizing the continuous radon adsorption and desorption function of the device.

[0039] Example 2

[0040] Based on Example 1, this embodiment provides a method for the combined elimination and control of radon gas and temperature and humidity, including the following steps:

[0041] Outdoor fresh air is treated by temperature regulation and filtration to 10-30℃ (not within the treatment range of this system; the treatment temperature is lower in winter and higher in summer) and then enters the mixing section 3 through the fresh air unit 4; after mixing with the return air that has been treated for radon removal and temperature and humidity, it is sent into the underground radon dissipation room 1 by the supply fan 2.

[0042] Air volume is 1000m³ 3 / h-10000m 3 The 20°C return air in the underground radon dispersing room 1 is first filtered by the primary and medium-efficiency filters 11, then enters the first-stage evaporator 12 for cooling and dehumidification, reducing the temperature to 0°C before entering the second-stage evaporator 13. There, it undergoes further deep cooling and dehumidification, becoming -40°C dry air, which then enters the radon continuous adsorption and desorption device 7. As the low-temperature, low-humidity radon-containing air passes through the adsorption module, the radon in the air is efficiently adsorbed (approximately 20 times more efficient than at room temperature). The radon-desorbed air, at -40°C, enters the first-stage condenser 14 and the heating section 15 of the heat recovery device, where its temperature is heated to 10-30°C (higher in winter and lower in summer, complementing the fresh air treatment temperature and reducing system energy consumption). It then enters the mixing section, where it mixes with the outdoor fresh air, and the temperature is adjusted to 25°C before being sent into the underground radon dispersing room 1 by the blower 2, achieving the purpose of removing radon from the room and controlling the room's temperature and humidity.

[0043] The exhaust air in the underground radon dispersing room 1 is heated to 40°C by the secondary condenser 5 and then enters the electric heater 6. The temperature is further heated to 120°C and then enters the desorption module of the radon gas continuous adsorption and desorption device 7. The high-temperature, low-radon-concentration exhaust air desorbs the radon gas in the module and then enters the cooling section 8 of the heat recovery device. After the temperature drops to 50°C, it is discharged to the outside by the exhaust fan 9.

[0044] The heating section 15 and the cooling section 8 of the heat recovery device are connected by a solution pipe and a solution pump 16, which continuously transfers heat from the exhaust air to the return air, thereby increasing the return air temperature and reducing system energy consumption.

[0045] The radon adsorption and desorption module (modified activated carbon) in the radon continuous adsorption and desorption device 7 can be moved in a staggered manner via the slide rail 18 installed at the bottom. When the module is not radon saturated, it should be located in the return air duct to efficiently adsorb and remove radon from the low-temperature, low-humidity return air. The other module is located in the exhaust air duct, where high-temperature exhaust air continuously desorbs radon from it. When any one of the three radon measuring sensors 17 evenly installed at the outlet of the return air duct detects radon, it indicates that the radon adsorption in this module is saturated and a radon desorption operation is required. This system uses a motor to drive the modules in the return and exhaust air ducts to be swapped. The radon-saturated module is moved to the exhaust air duct, and the desorbed module is moved to the return air duct for the next round of radon adsorption and desorption, thus realizing the continuous radon adsorption and desorption function of the device.

[0046] When the radon and temperature and humidity combined elimination control system is running, the automatic control mechanism adjusts the ratio of fresh air to return air by controlling the fresh air unit 4 and the return air unit 10 based on the real-time monitoring value of the radon concentration in the underground radon-emitting room 1. This accelerates the elimination of radon in the room, quickly creating a safe air quality environment for the staff in the room and meeting their immediate work needs. Specifically, when the radon concentration in the room is high, the proportion of fresh air is automatically increased to further enhance the radon removal capacity of the system.

[0047] In summary, this invention utilizes a two-stage compression refrigeration system with two-stage evaporators and condensers. First, air with high radon concentration is treated at low temperature and low humidity, becoming dry air at -40°C. This air then enters a radon continuous adsorption and desorption module filled with modified activated carbon for efficient adsorption and removal of radon from the air. Once the modified activated carbon module is saturated with radon, the room exhaust air is subjected to cascade heating (a two-stage condenser and an electric heater provide cascade heating). The high-temperature exhaust air then desorbs the radon from the saturated module. The two modules are staggered, one adsorbing and the other desorbing, achieving continuous and efficient removal of radon from underground radon-laden rooms.

[0048] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A radon gas and temperature / humidity combined elimination control system, characterized in that, include: The air supply section, exhaust section and return air section connected to the underground radon-emitting room (1); In the air supply section, the air inlet of the underground radon-dissipating room (1) is connected in sequence to the air supply fan (2), the air mixing section (3) and the fresh air fan (4). In the exhaust section, the exhaust vent of the underground radon dispersing room (1) is sequentially connected to a secondary condenser (5), an electric heater (6), a radon gas continuous adsorption and desorption device (7), a cooling section (8) of a heat recovery device, and an exhaust fan (9). In the return air section, the return air inlet of the underground radon dispersing room (1) is sequentially connected to a return air fan (10), a primary and secondary filter (11), a primary evaporator (12), a secondary evaporator (13), a radon gas continuous adsorption and desorption device (7), a primary condenser (14), a heating section (15) of a heat recovery device, and a mixing section (3). The radon continuous adsorption and desorption device (7) has a radon adsorption and desorption module, which uses modified activated carbon. The 20°C return air in the underground radon-dissipating room (1) is first filtered by a primary and medium-efficiency filter (11), and then enters the first-stage evaporator (12) for cooling and dehumidification. The temperature is reduced to 0°C and then enters the second-stage evaporator (13). It is further cooled and dehumidified to -40°C and then enters the radon continuous adsorption and desorption device (7). The air with a temperature of -40°C and after radon removal enters the first-stage condenser (14) and the heating section (15) of the heat recovery device. The temperature is heated to 10-30°C and then enters the mixing section. It is mixed with the outdoor fresh air and the temperature is adjusted to 25°C before being sent into the underground radon-dissipating room (1) by the blower (2). The exhaust air in the underground radon-emitting room (1) is heated to 40°C by the secondary condenser (5) and then enters the electric heater (6). The temperature is reheated to 120°C and then enters the radon gas continuous adsorption and desorption device (7). After that, it enters the cooling section (8) of the heat recovery device and the temperature is reduced to 50°C before being discharged to the outside.

2. The radon and temperature / humidity combined elimination control system according to claim 1, characterized in that, The heating section (15) and cooling section (8) of the heat recovery device are connected by a solution pipe and a solution pump (16) to transfer heat from the exhaust air to the return air.

3. The radon and temperature / humidity combined elimination control system according to claim 1, characterized in that, The primary and secondary filters (11), primary evaporator (12), secondary evaporator (13), radon continuous adsorption and desorption device (7), primary condenser (14), heating section (15) of heat recovery device, secondary condenser (5), electric heater (6), cooling section (8) of radon continuous adsorption and desorption device (7) and heat recovery device, and exhaust fan (9) can be integrated into one unit to form an integrated temperature and humidity control radon removal unit.

4. The radon and temperature / humidity combined elimination control system according to claim 1, characterized in that, The radon continuous adsorption and desorption device (7) has two radon adsorption and desorption modules. One radon adsorption and desorption module is located in the return air channel, and the other radon adsorption and desorption module is located in the exhaust air channel. The two radon adsorption and desorption modules can be moved and swapped between the return air channel and the exhaust air channel.

5. A method for the combined elimination and control of radon gas and temperature and humidity, characterized in that, The radon and temperature / humidity combined elimination control system according to any one of claims 1-4 includes the following steps: After being treated by temperature regulation and filtration, the outdoor fresh air enters the mixing section (3) through the fresh air unit (4); after being mixed with the return air that has been treated by radon removal and temperature and humidity control, it is sent into the underground radon-dissipating room (1) by the supply fan (2); The return air in the underground radon dissipation room (1) passes through the return air fan (10), primary and secondary filters (11), primary evaporator (12), secondary evaporator (13), radon continuous adsorption and desorption device (7), primary condenser (14), and the heating section (15) of the heat recovery device before entering the mixing section (3). After mixing with the outdoor fresh air, it is sent into the underground radon dissipation room (1) by the blower (2). The exhaust air in the underground radon dissipation room (1) is discharged to the outside through a two-stage condenser (5), an electric heater (6), a radon continuous adsorption and desorption device (7), a cooling section (8) of a heat recovery device, and an exhaust fan (9).

6. The radon gas and temperature / humidity combined elimination and control method according to claim 5, characterized in that, Outdoor fresh air is conditioned and filtered to 10-30℃ before entering the fresh air unit (4).

7. The radon gas and temperature / humidity combined elimination and control method according to claim 5, characterized in that, When the radon gas and temperature and humidity combined elimination control system is running, the automatic control mechanism adjusts the ratio of fresh air to return air by controlling the fresh air fan (4) and return air fan (10) based on the real-time monitoring value of radon concentration in the underground radon-emitting room (1), thereby accelerating the elimination speed of radon gas in the room.

8. The radon gas and temperature / humidity combined elimination and control method according to claim 5, characterized in that, Three radon gas measuring sensors are evenly installed inside the outlet of the return air duct. When any one of the radon gas measuring sensors detects radon gas, it indicates that the radon adsorption and desorption module in the return air duct has become saturated and a radon desorption operation is required.

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