Carbon dioxide removal device

Abstract

The invention relates to the technical field of carbon dioxide removal, and discloses a carbon dioxide removal device, which comprises a monitoring module for monitoring the concentration of carbon dioxide in an oxygen cabin in real time; the conversion module is used for converting and analyzing the information collected by the monitoring module; the control module corrects and restores the real carbon dioxide concentration value, and if the real carbon dioxide concentration value exceeds a threshold value, an alarm is triggered immediately; the removal module is used for reducing the concentration of carbon dioxide in the oxygen cabin. The monitoring module comprises a sampling unit which captures the concentration of carbon dioxide in the cabin in real time through a carbon dioxide concentration sensor, triggers infrared absorption change, converts the infrared absorption change into an analog voltage signal and outputs the analog voltage signal through the carbon dioxide concentration sensor, A / D conversion and a data processing algorithm are finely calibrated, and real-time accurate monitoring of the concentration of carbon dioxide is achieved. The measurement precision reaches + / -0.01%, the response time is less than 20 seconds, and the comprehensive coverage from slight concentration change to serious standard exceeding is realized, so that the health risk caused by carbon dioxide accumulation is greatly reduced.

Description

Technical Field

[0001] The invention relates to the technical field of carbon dioxide removal, and in particular to a carbon dioxide removal device. Background Art

[0002] In many fields such as modern industry and medical care, very ballast equipment plays an indispensable and key role. It covers a wide range, from the diving chambers relied on for deep-sea diving operations, to the highly-anticipated hyperbaric oxygen chambers in the field of medical rehabilitation, to the construction chambers that ensure the special working environment for workers in large-scale underground projects and deep-sea tunnel construction scenes. The application scenarios are rich, diverse and highly targeted.

[0003] During diving operations, divers must simulate high-pressure environments in a diving chamber to adjust their bodies and prevent decompression sickness before entering the water. However, this chamber is a closed space, and gas exchange relies on a limited ventilation circulation system. The human body exhales 4% to 5% carbon dioxide, which is easy to accumulate in the chamber. Normally, the carbon dioxide concentration is required to be controlled below 1%. Once it exceeds the standard, divers will experience headaches, dizziness, and shortness of breath in the early stage. When the concentration increases, the judgment and coordination will deteriorate. When faced with complex conditions such as undercurrents, equipment failures, and underwater creatures, it is very easy to drown due to poisoning, and decompression sickness will worsen, endangering life safety. In construction facilities, due to the dense personnel and energy consumption and heat generation of equipment, carbon dioxide is generated quickly and its circulation is blocked, and it is easy to accumulate exceeding the 2% safety threshold. In an environment with excessively high carbon dioxide concentration, construction workers will experience drowsiness, fatigue, and lack of concentration, which is easy to cause safety accidents due to internal carbon dioxide accumulation. Summary of the invention

[0004] In view of the deficiencies in the prior art, the present invention provides a carbon dioxide removal device, which solves the problem that the oxygen chamber, as a closed space, is prone to accumulation of carbon dioxide exceeding the limit, causing harm to the human body.

[0005] To achieve the above objectives, the present invention is implemented through the following technical solutions: A carbon dioxide removal device, comprising:

[0006] Monitoring module, real-time monitoring of carbon dioxide concentration in the oxygen chamber;

[0007] The conversion module converts and analyzes the information collected by the monitoring module;

[0008] The control module corrects and restores the actual carbon dioxide concentration value. If it exceeds the threshold, an alarm is triggered immediately;

[0009] Remove the module to reduce the concentration of carbon dioxide inside the oxygen chamber.

[0010] Preferably, the monitoring module includes:

[0011] The sampling unit uses a carbon dioxide concentration sensor to capture the infrared absorption changes caused by the carbon dioxide concentration in the cabin in real time and converts it into an analog voltage signal output.

[0012] Preferably, the conversion module comprises:

[0013] A conversion unit, which converts an analog signal output by the carbon dioxide concentration sensor into a digital signal;

[0014] The calibration unit establishes a voltage-concentration conversion mathematical model based on the least squares fitting method to calibrate the concentration data.

[0015] Preferably, the control module includes:

[0016] A judgment unit, which judges whether the carbon dioxide concentration exceeds a preset safety threshold after filtering and preprocessing;

[0017] The sound and light alarm unit implements a graded alarm strategy based on the degree of excess when it determines that the carbon dioxide concentration exceeds the preset safety threshold.

[0018] Preferably, the removal module comprises:

[0019] Exhaust unit, which performs ventilation operations in the oxygen cabin;

[0020] The balance unit establishes a flow-pressure correlation model based on the ideal gas state equation to maintain the dynamic balance of gas inside the oxygen chamber.

[0021] Preferably, the removal module further comprises an adsorption unit, which adsorbs carbon dioxide in the cabin at a constant rate through an adsorption mechanism.

[0022] Preferably, the carbon dioxide concentration sensor is installed at the center of the top of the cabin, at a height of 0.5-1m from the breathing plane of the personnel.

[0023] Preferably, the adsorption mechanism comprises a basic frame, a filling column is arranged inside the basic frame, the upper layer of the filling column is high specific surface area activated carbon fiber, the middle layer is metal organic framework material, and the lower layer is modified molecular sieve, and a fan is arranged on one side of the outer wall of the basic frame.

[0024] Preferably, the adsorption mechanism further includes a regeneration component therein, and the regeneration component includes an extension frame, and a heating wire is installed inside the extension frame.

[0025] Preferably, when the concentration of carbon dioxide entering and leaving the filling column is less than a set value, the regeneration component starts vacuum heating regeneration.

[0026] The present invention provides a carbon dioxide removal device having the following beneficial effects:

[0027] 1. The present invention realizes real-time and accurate monitoring of carbon dioxide concentration through carbon dioxide concentration sensor, fine calibration A / D conversion and data processing algorithm, with a measurement accuracy of ±0.01% and a response time of less than 20 seconds. It cooperates with graded sound and light alarms to cover all aspects from slight concentration changes to serious exceeding of the standard, ensuring that personnel can detect abnormalities in the first time and greatly reducing the health risks caused by carbon dioxide accumulation.

[0028] 2. While efficiently discharging carbon dioxide, the present invention uses high-precision pressure sensor closed-loop feedback and optimized PID control to strictly control the pressure fluctuation in the cabin within ±0.02ATA, which meets the stringent pressure requirements of non-normal pressure equipment, ensures the safety of the equipment structure, and ensures that personnel are in a stable pressure environment, maintain normal physiological functions, and improve the reliability of equipment operation and the comfort of personnel operation.

[0029] 3. The present invention optimizes the adsorption process by combining a multi-layer composite adsorption material filling column with an adaptive adsorption kinetic model. The advantages of each layer of material complement each other. Graphene modification improves the adsorption capacity and rate, UiO-66 enhances selectivity, and molecular sieves ensure stability. The variable frequency fan is used for intelligent speed regulation, and the adsorption efficiency is high.

[0030] 4. The present invention adopts the vacuum temperature change combined regeneration method after adsorption saturation, and scientifically sets the process parameters to efficiently desorb carbon dioxide for recycling, thereby reducing the cost of consumables, ensuring the long-term stable operation of the device, and continuously maintaining a low carbon dioxide concentration level in an extraordinary pressure environment, protecting the lives and health of personnel and the normal operation of equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 is a three-dimensional diagram of a carbon dioxide removal device in the present invention;

[0032] Figure 2 It is a structural explosion diagram of the adsorption mechanism in the present invention.

[0033] Among them, 1. basic frame; 2. filling column; 3. activated carbon fiber; 4. metal organic framework material; 5. modified molecular sieve; 6. fan; 7. extension frame; 8. heating wire. DETAILED DESCRIPTION

[0034] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0035] Please see attached Figure 1 - Attachment Figure 2 , an embodiment of the present invention provides a carbon dioxide removal device, comprising:

[0036] 1. Monitoring module

[0037] In this embodiment, the main function of the monitoring module is to capture the infrared absorption changes caused by the carbon dioxide concentration in the cabin in real time through the carbon dioxide concentration sensor and convert them into analog voltage signal output, as follows:

[0038] 1.1 Sampling Unit

[0039] In this embodiment, a sensor based on the principle of non-dispersive infrared is used as a carbon dioxide concentration sensor. The sensor monitors the carbon dioxide concentration in real time under an abnormal pressure environment according to the Lambert-Beer law A=ε×c×l (where A is absorbance, ε is molar absorption coefficient, c is the amount of carbon dioxide, and l is the optical path length). The installation position of the sensor is a gas mixing uniform area selected in the oxygen cabin of the equipment according to computational fluid dynamics (CFD) simulation. The installation position of the carbon dioxide concentration sensor in this embodiment is selected at the top center of the oxygen cabin body and 0.5-1m above the breathing plane of the personnel after multiple simulations, considering the obstruction of the internal structural parts of the equipment to the airflow, the position of the vents and the flow direction, and the heat convection factors caused by the activities of the personnel, and is electrically connected to the subsequent circuit through a sealed connection structure;

[0040] After the system is started, the carbon dioxide concentration sensor continues to work at a high-frequency sampling frequency of 20 times per second, capturing the infrared absorption changes caused by the carbon dioxide concentration in the cabin in real time and converting them into analog voltage signals for output. The signal is first processed by the signal conditioning circuit, which includes a second-order Butterworth low-pass filter with a cutoff frequency of 150Hz to effectively filter out high-frequency noise interference, and a programmable gain amplifier (based on the sensor sensitivity and the A / D converter input range requirements, the amplification factor is dynamically adjusted in the range of 1-10 times to ensure that the input A / D converter signal is adapted to the range). After processing, the signal is transmitted to the A / D converter, which quickly converts according to the set sampling rate and accuracy, and efficiently transmits the digital signal to the CPU memory buffer via the high-speed data bus with the help of the interrupt mechanism, SPI protocol and the attached CRC check code. After the CPU reads the data, it restores the true carbon dioxide concentration value based on the calibration formula, and then activates the adaptive Kalman filter algorithm. It iteratively updates the predicted value and observed value weights based on the state-space model and the observation equation, accurately smoothes the concentration data, and tracks the dynamic change trend of the concentration. At the same time, it uses a time series prediction model based on the long short-term memory network (LSTM) to optimize the network weights by training a large amount of historical data covering various working conditions, predicting the concentration trend in the next 1 to 2 minutes and detecting the risk of exceeding the standard in advance.

[0041] 2. Conversion module

[0042] In this embodiment, the main function of the conversion module is to convert and analyze the information collected by the monitoring module, as follows:

[0043] 2.1 Conversion Unit

[0044] In this embodiment, a 24-bit ∑-Δ type A / D converter is used, and the SPI communication protocol is followed. Under the drive of the synchronous clock pulse, the analog signal is converted into a 24-bit digital code. The conversion time is less than 5μs. After each conversion is completed, the data transmission is triggered by the interrupt mechanism, and the digital code data is transmitted to the CPU memory buffer via the high-speed data bus. The transmission is accompanied by a CRC16 check code. After the CPU receives the data and verifies that it is correct, it is stored in the data queue and waits for the next step of analysis. The sensor output analog signal is converted into a digital signal through the above steps. In the converter configuration stage, according to the sensor output voltage range (0-5V corresponds to 0% to 5% carbon dioxide concentration), a known voltage value (covering multiple typical values ​​within the sensor range, such as 0.5V, 1.5V, 3V, 4.5V, etc.) is output through a precision voltage source to simulate the sensor signal and input it into the A / D converter for calibration;

[0045] 2.2 Calibration Unit

[0046] In this embodiment, the calibration process is based on the least squares method to fit and establish a voltage-concentration conversion mathematical model, and the conversion formula is:

[0047] C=α×V 3 +b×V 3 +c×V+d

[0048] Where C is the carbon dioxide concentration (%), V is the voltage value corresponding to the digital quantization after A / D conversion, α, b, c, d are the calibration coefficients to be fitted, and multiple sets of calibration data points (V i ,C i ), and solve the minimum value of the objective function by the least squares method:

[0049]

[0050] Among them, C predicted To predict the concentration, n is the number of calibration data groups, and the optimal values ​​of a, b, c, and d are determined. The conversion error after calibration is controlled within the concentration error range of ±0.005V to ensure the accuracy of subsequent concentration restoration. The predicted value and the observed value weights are iteratively updated to accurately smooth the concentration data and track the dynamic change trend of the concentration, effectively reducing the impact of random noise and systematic errors.

[0051] 3. Control module

[0052] In this embodiment, the function of the control module is to correct and restore the actual carbon dioxide concentration value. If it exceeds the threshold, an alarm is immediately triggered, as follows:

[0053] 3.1. Judgment Unit

[0054] In this embodiment, the CPU and control module are industrial-grade embedded CPUs based on the ARM Cortex-A9 core and run an embedded real-time operating system (RTOS). The carbon dioxide safety threshold and pressure safety upper and lower limit parameters set according to the purpose of the equipment are pre-stored, and the threshold value of the carbon dioxide concentration is judged. The module receives the data of the A / D conversion module and controls the ventilation, carbon dioxide adsorption and sound and light alarm inside the oxygen chamber accordingly. At the same time, it has a communication interface with an external host computer for remote monitoring and parameter adjustment.

[0055] 3.2. Sound and light alarm unit

[0056] In this embodiment, when the judgment unit determines that the carbon dioxide concentration exceeds the preset safety threshold after filtering and prediction processing, a fine-grade alarm strategy is implemented according to the degree of exceeding the standard. In case of slight exceeding the standard (exceeding the threshold of 0% to 0.015%), the high-brightness LED light in the sound and light alarm device is controlled to flash green at a frequency of 0.5Hz, and the buzzer sounds intermittently (sounds for 0.3 seconds and stops for 1.5 seconds). This level reminds the cabin personnel and monitoring personnel to pay attention to the rising trend of carbon dioxide concentration; in case of moderate exceeding the standard (exceeding the threshold of 0.015% to 0.03%), the LED light is always on yellow light, the buzzer sounds continuously, and the volume is adjusted to 70dB to strengthen the warning intensity; in case of severe exceeding the standard (exceeding the threshold by more than 0.03%), the LED light turns to red strong light flashing (flashing frequency 1Hz), and the buzzer sounds continuously at a high decibel of 90dB until the concentration drops back to the safe range. The alarm logic is written as part of the CPU interrupt service program to ensure timely response, and the alarm parameters can be remotely monitored and adjusted through the host computer.

[0057] 4. Remove modules

[0058] In this embodiment, the function of the removal module is to remove the carbon dioxide accumulation in the oxygen cabin when the concentration is too high, as follows:

[0059] 4.1 Exhaust unit

[0060] In this embodiment, the CPU outputs a pulse width modulation (PWM) control signal to drive the CO2 exhaust valve, the intake valve and the exhaust valve to operate accurately. The CO2 exhaust valve is based on the flow characteristic equation:

[0061]

[0062] Among them, Q out is the carbon dioxide discharge flow rate (m 3 / s), K v1 is the valve flow coefficient (determined by the valve structure and size, and the value is obtained through experimental measurement), ΔP1 is the pressure difference before and after the valve (Pa ), ρ1 is the gas density (kg / m 3 , calculated by the gas state equation according to the temperature and pressure in the cabin), D1 is the PWM duty cycle (value range 0-1). At the initial stage of exceeding the standard, D1 = 0.1, and then every 8 seconds, the duty cycle is increased by 0.03 according to the concentration exceeding the standard gradient (according to each exceeding threshold value of 0.005%), up to a maximum of 0.8, to efficiently discharge carbon dioxide;

[0063] 4.2 Balance Unit

[0064] In this embodiment, the intake valve and the exhaust valve cooperate to maintain the dynamic balance of the cabin pressure. Based on the ideal gas state equation PV = nRT and the principle of mass conservation, a complex flow-pressure correlation model is established. Assume that the intake flow rate Q in , Exhaust flow Q out ,have:

[0065]

[0066] Among them, ρ2 and ρ3 are the intake and exhaust gas densities, Δn is the change in carbon dioxide moles per unit time, M co2 is the molar mass of carbon dioxide, R is the gas constant, and T is the cabin temperature.

[0067] By dynamically adjusting the intake valve and exhaust valve PWM duty ratio D2, D3 (value range 0-1), with the help of high-precision pressure sensor (accuracy ± 0.005ATA) closed-loop feedback, using proportional-integral-differential, PID control algorithm, according to the pressure deviation:

[0068] e=P set -P current

[0069] Calculate the control output u:

[0070]

[0071] Among them, K p , K i , K d The PID coefficient has been debugged and optimized to ensure that the pressure fluctuation in the cabin is within the allowable narrow range (±0.02ATA), achieving ventilation and air exchange while stabilizing the pressure;

[0072] 4.3 Adsorption unit

[0073] In this embodiment, the carbon dioxide adsorption device adopts a multi-layer composite adsorption material filling column structure, the upper layer is graphene modified activated carbon fiber 3 (specific surface area exceeds 2000m 2 / g, rich in micropores and mesopores, which are conducive to carbon dioxide adsorption), the middle layer is the metal organic framework material 4UiO-66, whose crystal structure has a high selective adsorption capacity for carbon dioxide, and the lower layer is aluminosilicate modified molecular sieve 5, which can enhance the adsorption stability and improve the resistance to water vapor interference. The adsorption process is optimized according to the adsorption kinetics double resistance model and the adsorption isotherm equation;

[0074] Adsorption kinetics dual resistance model:

[0075]

[0076] Among them, q is the adsorption capacity per unit adsorbent, k1 and k2 are the external diffusion and internal diffusion mass transfer coefficients, C is the gas phase carbon dioxide concentration, and C eq is the adsorption equilibrium concentration;

[0077] Adsorption isotherm equation:

[0078]

[0079] Among them, q eq is the equilibrium adsorption amount, q m is the maximum monolayer adsorption capacity, b and n are empirical constants;

[0080] The adsorption device is equipped with a variable frequency fan 6, which intelligently adjusts the speed (range 1000-2000rpm) according to the gas flow demand and carbon dioxide concentration in the cabin, drives the gas in the cabin to flow through the adsorption column at an appropriate linear speed (1-3m / s) to ensure high adsorption efficiency. The adsorption process continues until the carbon dioxide concentration drops below the safety threshold, and then switches to the regeneration mode according to the preset adsorption cycle (running for 2-3 hours) or the adsorption saturation judgment condition (by monitoring the inlet and outlet concentration difference of the adsorption column is less than the set 0.05%). Regeneration adopts a vacuum temperature combination method. First, the adsorption column is evacuated to 2-5kPa to remove the adsorbed gas, and then the heating wire 8 is used to slowly heat it to 80-120℃ (heating rate 2-5℃ / min) to promote carbon dioxide desorption. The desorbed gas is condensed and recovered. The regeneration cycle is 1-2 hours, and the regeneration efficiency can reach 85% to 95%, ensuring the long-term operation of the adsorption device.

[0081] Working principle: The present invention provides a carbon dioxide removal device, which works in coordination with four main modules, namely, a monitoring module, a conversion module, a control module and a removal module, to monitor the carbon dioxide concentration in the oxygen cabin in real time, take timely measures to remove it when the concentration exceeds the standard, and maintain the cabin pressure stable to ensure a safe and suitable cabin environment, as follows:

[0082] The sensor based on the principle of non-dispersive infrared is used to monitor the carbon dioxide concentration in the oxygen chamber under the non-pressure environment in real time according to the specific optical absorption law (Lambert-Beer law). The installation position of the sensor is determined multiple times through computational fluid dynamics (CFD) simulation. The factors such as the obstruction of the internal structural parts of the equipment to the airflow, the position of the vents and the flow direction, and the heat convection caused by personnel activities are comprehensively considered to ensure that the gas at this position is evenly mixed and can accurately reflect the carbon dioxide concentration in the breathing zone of personnel. After the system is started, the sensor continues to work at a high-frequency sampling frequency of 20 times per second to capture the infrared absorption changes caused by the carbon dioxide concentration and convert it into an analog voltage signal output. After being transmitted to the CPU through the A / D converter, the CPU not only restores the real carbon dioxide concentration value according to the calibration formula, but also enables the adaptive Kalman filter algorithm to smooth the concentration data and track the dynamic change trend of the concentration. At the same time, the time series prediction model based on the long short-term memory network (LSTM) is used to optimize the network weight by training a large amount of historical data covering various working conditions, so that the trend of carbon dioxide concentration in the next 1 to 2 minutes can be predicted, and whether there is a risk of exceeding the standard in advance;

[0083] The conversion unit in the conversion module adopts a 24-bit A / D converter and follows the SPI communication protocol. Under the drive of the synchronous clock pulse, it quickly converts the analog signal received from the monitoring module into a 24-bit digital code. The conversion time is less than 5 microseconds. After each conversion is completed, the data transmission is triggered by the interrupt mechanism, and the digital encoded data is transmitted to the CPU memory buffer via the high-speed data bus. The transmission is also accompanied by a CRC16 check code to ensure the accuracy of data transmission.

[0084] During the converter configuration phase, calibration is required to ensure the accuracy of subsequent concentration restoration. According to the sensor output voltage range (0-5V corresponds to 0% to 5% carbon dioxide concentration), an analog signal covering multiple typical values ​​within the sensor range is output by a precision voltage source and input into the A / D converter for calibration. The calibration process establishes a voltage-concentration conversion mathematical model based on least squares fitting. By using multiple sets of calibration data points, the minimum value of the objective function is solved to determine the optimal calibration coefficient, thereby controlling the conversion error within the corresponding concentration error range, making the final restored carbon dioxide concentration value more accurate and reliable;

[0085] The CPU and control unit in the control module are based on an industrial-grade embedded CPU with an ARMCortex-A9 core and run an embedded real-time operating system (RTOS). The unit pre-stores parameters such as the carbon dioxide safety threshold, pressure safety upper and lower limits set according to the purpose of the equipment, and performs threshold judgment on the carbon dioxide concentration data received from the conversion module to determine whether the carbon dioxide concentration in the cabin exceeds the standard. When the judgment unit determines that the carbon dioxide concentration exceeds the preset safety threshold after filtering and prediction processing, it will implement a fine-grained alarm strategy based on the degree of excess. For example, when the standard is slightly exceeded, the high-brightness LED light in the sound and light alarm device is controlled to flash green at a frequency of 0.5Hz, and the buzzer sounds intermittently, prompting the cabin personnel and monitoring personnel to pay attention to the rising trend of carbon dioxide concentration; when the standard is moderately exceeded or severely exceeded, the warning intensity is increased through different LED light displays and buzzer volume settings until the concentration drops back to the safe range. In addition, the alarm logic is written as part of the CPU interrupt service program to ensure timely response. At the same time, the alarm parameters can be remotely monitored and adjusted through the host computer;

[0086] When the carbon dioxide concentration in the cabin exceeds the standard, the exhaust unit in the removal module starts to work. The CPU outputs a pulse width modulation (PWM) control signal to drive the carbon dioxide exhaust valve, the intake valve and the exhaust valve to move precisely. The carbon dioxide exhaust valve works according to a specific flow characteristic equation. A lower PWM duty cycle is set at the initial stage of exceeding the standard. After that, the duty cycle is increased by 0.03 every 8 seconds according to the concentration exceeding the standard gradient (by 0.005% for each exceeding threshold), up to a maximum of 0.8. In this way, carbon dioxide is efficiently discharged, and the intake valve and the exhaust valve work together to maintain the dynamic balance of the cabin pressure. Based on the ideal gas state equation and the principle of mass conservation, a complex flow-pressure correlation model is established. By dynamically adjusting the PWM duty cycle of the intake valve and the exhaust valve (value range 0-1), with the help of high-precision pressure sensor closed-loop feedback, and using the proportional-integral-differential (PID) control algorithm, the control output is calculated based on the pressure deviation to ensure that the cabin pressure fluctuation is within the allowable range, and ventilation and air exchange are achieved while stabilizing the pressure, which not only ensures the discharge of carbon dioxide, but also maintains the stability of the cabin pressure environment, avoiding adverse effects on the personnel and equipment in the cabin;

[0087] The carbon dioxide adsorption mechanism adopts a multi-layer composite adsorption material filling column 2 structure, the upper layer is graphene modified activated carbon fiber 3 (specific surface area exceeds 2000, rich in micropores and mesopores that are conducive to carbon dioxide adsorption), the middle layer is metal organic framework material 4UiO-66, whose crystal structure has a high selective adsorption capacity for carbon dioxide, and the lower layer is aluminosilicate modified molecular sieve 5, which can enhance adsorption stability and improve resistance to water vapor interference, and optimize the adsorption process according to the adsorption kinetics double resistance model and adsorption isotherm equation;

[0088] The adsorption device optimizes the adsorption process based on the adsorption kinetics double resistance model and the adsorption isotherm equation. The matching variable frequency fan 6 intelligently adjusts the speed (range 1000-2000rpm) according to the gas flow demand and carbon dioxide concentration in the oxygen cabin, driving the gas in the cabin to flow through the adsorption column at an appropriate linear speed (1-3m / s) to ensure high adsorption efficiency. When the adsorption process continues until the carbon dioxide concentration drops below the safety threshold, or the adsorption is saturated according to the preset adsorption cycle (running for 2-3 hours) or by monitoring the adsorption column inlet and outlet concentration difference less than the set 0.05%, the adsorption device will switch to the regeneration mode. Regeneration adopts the vacuum temperature combination method. First, the adsorption column is evacuated to 2-5kPa to remove the adsorbed gas, and then the heating wire 8 is slowly heated to 80-120℃ (heating rate 2-5℃ / min) to promote carbon dioxide desorption. The desorbed gas is condensed and recycled. The regeneration cycle is 1-2 hours, and the regeneration efficiency can reach 85% to 95%, ensuring that the adsorption device can circulate and operate for a long time and continuously adsorb and remove carbon dioxide in the cabin.

[0089] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A carbon dioxide removal device, characterized in that: include: Monitoring module, real-time monitoring of carbon dioxide concentration in the oxygen chamber; The conversion module converts and analyzes the information collected by the monitoring module; The control module corrects and restores the actual carbon dioxide concentration value. If it exceeds the threshold, an alarm is triggered immediately; Remove the module to reduce the concentration of carbon dioxide inside the oxygen chamber.

2. A carbon dioxide removal device according to claim 1, characterized in that: The monitoring module comprises: The sampling unit uses a carbon dioxide concentration sensor to capture the infrared absorption changes caused by the carbon dioxide concentration in the cabin in real time and converts it into an analog voltage signal output.

3. A carbon dioxide removal device according to claim 1, characterized in that: The conversion module comprises: A conversion unit, which converts an analog signal output by the carbon dioxide concentration sensor into a digital signal; The calibration unit establishes a voltage-concentration conversion mathematical model based on the least squares fitting method to calibrate the concentration data.

4. A carbon dioxide removal device according to claim 1, characterized in that: The control module comprises: A judgment unit, which judges whether the carbon dioxide concentration exceeds a preset safety threshold after filtering and preprocessing; The sound and light alarm unit implements a graded alarm strategy based on the degree of excess when it determines that the carbon dioxide concentration exceeds the preset safety threshold.

5. A carbon dioxide removal device according to claim 1, characterized in that: The removal module comprises: Exhaust unit, which performs ventilation operations in the oxygen cabin; The balance unit establishes a flow-pressure correlation model based on the ideal gas state equation to maintain the dynamic balance of gas inside the oxygen chamber.

6. A carbon dioxide removal device according to claim 5, characterized in that: The removal module further comprises an adsorption unit, which adsorbs carbon dioxide in the cabin at a constant rate through an adsorption mechanism.

7. A carbon dioxide removal device according to claim 2, characterized in that: The carbon dioxide concentration sensor is installed at the center of the top of the cabin, at a height of 0.5-1m from the breathing plane of the personnel.

8. A carbon dioxide removal device according to claim 6, characterized in that: The adsorption mechanism comprises a basic frame (1), a filling column (2) is arranged inside the basic frame (1), the upper layer of the filling column (2) is a high specific surface area activated carbon fiber (3), the middle layer is a metal organic framework material (4), and the lower layer is a modified molecular sieve (5), and a fan (6) is arranged on one side of the outer wall of the basic frame (1).

9. A carbon dioxide removal device according to claim 8, characterized in that: The adsorption mechanism further comprises a regeneration component inside, and the regeneration component comprises an extension frame (7), and a heating wire (8) is installed inside the extension frame (7).

10. A carbon dioxide removal device according to claim 9, characterized in that: When the concentration of carbon dioxide entering and leaving the filling column (2) is less than a set value, the regeneration component starts vacuum heating regeneration.

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