Portable marine environment air salinity detection device and detection method

Abstract

This invention relates to the field of marine environmental air salinity monitoring technology. Currently, most commonly used salinity measurement technologies and methods are limited to measuring salinity in water. These methods involve complex optical path calculations and calibrations, which cannot meet the monitoring needs of marine operational equipment and outdoor facilities in coastal areas. This invention provides a portable marine environmental air salinity detection device and method. The device dissolves the salt in water vapor in the air into the water of a humidifier. A temperature sensor is used to compensate for the conductivity of the mixture. The air salinity is obtained by measuring the conductivity of the electrodes immersed in the mixture. The measurement method is based on conductivity and does not need to consider the influence of external environmental factors such as vibration and angle during use. It can be used in continuous motion, is not limited by space, has strong anti-interference ability, and is suitable for marine environmental monitoring in complex climates.

Description

Technical Field

[0001] This invention relates to the field of marine environmental air salinity monitoring technology, and more specifically, to a portable marine environmental air salinity detection device and detection method. Background Technology

[0002] Air salinity refers to the mass of all salts, including sulfates, nitrates, and chlorides, dissolved in a unit volume of water vapor. For marine and coastal areas, air salinity is a crucial indicator of air quality and is of significant importance to marine operational equipment and outdoor facilities in coastal areas. However, most marine operational equipment and outdoor facilities operate in harsh environments, making it difficult to measure air salinity using sophisticated equipment. Due to water vapor evaporation over the sea surface, the air in marine environments contains a large amount of highly saline water vapor. This high-salinity water vapor adheres to the surfaces of marine operational equipment and outdoor facilities in coastal areas for extended periods, causing adverse effects such as metal corrosion, reduced material durability, and impaired electrical conductivity. Real-time monitoring of air salinity in marine environments is beneficial for the regular maintenance of older equipment and the installation and deployment of new equipment.

[0003] Currently used salinity measurement techniques include conductivity and refractive index methods, and the corresponding detection devices are mostly limited to measuring salinity in water. Chinese Patent 201610153590.0 discloses an air salinity monitoring method and device based on coreless fiber cavity sensing, comprising a pump source, a wavelength division multiplexer (WDM), erbium-doped fiber, and an optical fiber isolator (ISO). The output is connected to an optical spectrum analyzer (OSA) and the WDM, forming a ring cavity. The air salinity value is calibrated using the curve relationship between air salinity and laser peak wavelength. While this invention's monitoring method has high measurement accuracy, the detection device is highly experimental. The OSA is a precision optical instrument requiring a stable and fixed platform during detection. The detection method involves complex optical path calculations and calibrations; even small displacements can introduce significant deviations, necessitating calibration after repositioning before use. Furthermore, the unit is extremely expensive and highly susceptible to interference from external factors in complex marine environments. Therefore, the entire device is not suitable for marine operations or coastal outdoor facilities. Balancing the accuracy and practicality of air salinity measurement methods and devices has become a major issue of discussion in the field of air salinity measurement.

[0004] In summary, monitoring marine air salinity is crucial for marine operational equipment and outdoor facilities in coastal areas. Currently, there are no portable marine air salinity detection devices on the market, and existing methods for measuring marine air salinity cannot meet the monitoring needs of marine operational equipment and outdoor facilities in coastal areas. Developing a portable marine air salinity sensor is an urgent problem to be solved in the field of marine environmental monitoring. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the present invention aims to provide a portable marine environment air salinity detection device and detection method. This invention dissolves the salt in water vapor in the air into the water of a humidifier, uses a temperature sensor to compensate for the temperature of the conductivity, and obtains the air salinity by measuring the conductivity of the electrodes immersed in the mixture.

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

[0007] A humidifier for detecting salinity includes a temperature sensor and several arrayed electrode probes disposed inside the humidifier. The signal output terminals of the arrayed electrode probes and the temperature sensor are connected to the third set of signal input terminals of the control system circuit through a sensor signal transmission interface. It also includes a humidifier air inlet, a humidifier water inlet, a humidifier exhaust port, and a humidifier drain port. The humidifier exhaust port and the humidifier water inlet are located on the same side of the humidifier, as are the humidifier air inlet and the humidifier drain port. The horizontal positions of the humidifier exhaust port and the humidifier water inlet are higher than those of the humidifier air inlet and the humidifier drain port. Several stirring paddles are disposed at the bottom of the inner wall of the humidifier.

[0008] A portable marine environment air salinity detection device, based on the aforementioned humidifier for salinity detection, includes a housing and an air salinity detection system placed inside the housing. A humidity sensor is installed on the outer wall of the housing. The air salinity detection system includes a control system circuit, an airflow channel, and a water flow channel. The airflow channel and the water flow channel are integrated within the humidifier. The control system circuit realizes real-time control of the airflow channel and the water flow channel through a signal output terminal. The signal input terminal of the control system circuit receives signals from an array-type electrode probe, a temperature sensor, and a humidity sensor.

[0009] Furthermore, the airflow channel includes a miniature air pump and a flow meter. The miniature air pump is connected to the air inlet via a one-way air guide tube A, which is located outside the housing. The exhaust port of the miniature air pump is connected to the air inlet of the flow meter via a one-way air guide tube B. The exhaust port of the flow meter is connected to the air inlet of the humidifier to form a one-way air path. The miniature air pump draws air from the marine environment, and the flow meter detects the air flow rate in real time. The airflow enters the humidifier through the one-way air path. The salt in the airflow dissolves in the pure water to form a mixture. The conductivity of the mixture is detected using an array of electrode probes and a control system circuit.

[0010] Furthermore, the water inlet of the water flow channel is located outside the housing, and an inlet valve is installed between the inlet and the flow metering micro liquid pump. The outlet of the flow metering micro liquid pump is connected to the humidifier inlet through a one-way guide pipe, and the mixed liquid is discharged through the drain valve connected to the humidifier drain outlet and the drain outlet located outside the housing.

[0011] Furthermore, the control system circuit includes a microcontroller, the first set of signal output terminals of the microcontroller being connected to a micro air pump, the second set of signal output terminals being connected to a flow meter micro liquid pump, the third set of signal output terminals being connected to the control terminal of the airflow meter, the first set of signal input terminals being connected to the signal output terminal of the airflow meter, the second set of signal input terminals being connected to the signal output terminal of the humidity sensor, and the third set of signal input terminals being connected to the sensor signal transmission interface of the humidifier; the control system circuit also includes a power supply circuit for powering the circuit components inside the housing.

[0012] A method for detecting air salinity in a marine environment, based on the aforementioned portable air salinity detection device, involves a flow metering micro-pump drawing pure water into a humidifier, and a micro-air pump drawing air from the marine environment into the humidifier via an airflow channel. Salts in the water vapor of the air mix and dissolve thoroughly with the pure water in the humidifier to form a mixture. A temperature sensor compensates for the conductivity at different temperatures, and an array of electrode probes detects changes in the conductivity of the mixture to obtain the air salinity. The specific steps are as follows:

[0013] Step 1. After initializing the control system circuit, complete the electrode sampling calibration and temperature sampling calibration, and use a flow meter micro liquid pump to draw pure water into the humidifier until the water volume reaches the preset value and then turn off the flow meter micro liquid pump.

[0014] Step 2. The control system circuit drives the micro air pump to draw the air to be tested into the airflow channel. When the air flow reaches the preset value, the micro air pump is turned off. During the air extraction process, under the action of the stirring paddle, the salt in the water vapor in the air is fully dissolved in the pure water to form a mixture. The conductivity of the mixture is detected by an array electrode probe, and the temperature sensor is detected by a temperature sensor.

[0015] Step 3. The microcontroller calculates the conductivity of the mixture by receiving the conductivity and temperature signals of the mixture, calculates the salinity in the air based on the conductivity and the volume of the extracted airflow, discharges the mixture through the drain outlet, and extracts pure water to rinse the humidifier for the next test.

[0016] Furthermore, the flow metering micro-pump draws water in such a way that it completely submerges the temperature sensor within the humidifier.

[0017] In summary, the invention has the following beneficial effects:

[0018] The unidirectional airflow channel of this invention compresses the air to be tested into the humidifier. The air to be tested mixes with the pure water in the humidifier, dissolving the various salt ions to be tested in the water vapor of the air into the pure water. The conductivity of the electrodes immersed in the pure water is measured, and a temperature sensor is used to compensate for the conductivity of the array electrode probe. The measurement method is based on conductivity and does not need to consider the influence of external environmental factors such as vibration and angle during use. It can be used in continuous motion, is not limited by space, has a simple measurement method, and the measuring device has a simple structure, small size, and is easy to carry. It has low manufacturing cost and can be reused multiple times. In the later maintenance, faulty modules can be replaced individually, reducing maintenance costs. The connection is stable, and the anti-interference ability is strong. It is suitable for marine environmental testing in complex climates. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the sensing device structure of the present invention;

[0020] Figure 2 This is a schematic diagram of the humidifier of the present invention;

[0021] Figure 3 This is a schematic diagram of the gas flow direction to be measured according to the present invention;

[0022] Figure 4 This is a schematic diagram of the present invention;

[0023] Figure 5 This is a flowchart of the control process of the sensing device of the present invention.

[0024] In the diagram: 1. One-way air guide tube A, 2. Airflow meter, 3. One-way air guide tube B, 4. Flow meter micro liquid pump, 5. Inlet valve, 6. Inlet, 7. One-way liquid guide tube, 8. Drain valve, 9. Drain, 10. Exhaust port, 11. Exhaust valve, 12. Humidifier, 13. Air inlet, 14. Micro air pump, 15. First group signal output terminal, 16. First group signal input terminal, 17. Humidity sensor, 18. Second group signal input terminal, 19. Control system circuit, 20. Third group signal input terminal, 21. Humidifier exhaust port, 22. Sensor signal transmission interface, 23. Temperature sensor, 24. Agitator, 25. Humidifier water inlet, 26. Array electrode probe, 27. Humidifier drain port, 28. Humidifier air inlet. Detailed Implementation

[0025] The present invention will now be described in further detail with reference to the accompanying drawings.

[0026] It should be noted that, for ease of description, the descriptions of direction in the following text are consistent with the directions in the accompanying drawings, but they do not limit the structure of the present invention.

[0027] like Figures 1-5As shown, this invention discloses a humidifier for detecting salinity, including a temperature sensor 23 and several arrayed electrode probes 26 disposed inside the humidifier 12. The signal output terminals of the arrayed electrode probes 26 and the temperature sensor 23 are connected to the third set of signal input terminals 20 of the control system circuit 19 through a sensor signal transmission interface 22. It also includes a humidifier air inlet 28, a humidifier water inlet 25, a humidifier exhaust port 21, and a humidifier drain port 27. The humidifier exhaust port 21 and the humidifier water inlet 25 are located on the same side of the humidifier 12, and the humidifier air inlet 28 and the humidifier drain port 27 are also located on the same side of the humidifier 12. The horizontal positions of the humidifier exhaust port 21 and the humidifier water inlet 25 are higher than those of the humidifier air inlet 28 and the humidifier drain port 27. Several stirring paddles 24 are disposed at the bottom of the inner wall of the humidifier 12. After gas and water enter the humidifier 12, thorough stirring helps the salt in the water vapor in the air dissolve in the water to form a mixture. Figure 1 In the embodiment shown, two stirring paddles 24 are provided, and the number of stirring paddles 24 can be adjusted according to actual needs during use.

[0028] This invention also discloses a portable marine environment air salinity detection device. Based on the humidifier used for salinity detection described above, the salt in the water vapor of the air is dissolved in the pure water of the humidifier 12. The salt in the marine environment mainly exists in the water vapor of the air, with a very small portion in the aerosols of the air. Because the salt content in the aerosols is much smaller than that in the water vapor, it is negligible. The device includes a shell and an air salinity detection system placed inside the shell. A humidity sensor 17 is installed on the outer wall of the shell. The air salinity detection system includes a control system circuit 19, an airflow channel, and a water flow channel. The airflow channel and the water flow channel are integrated in the humidifier 12. The control system circuit 19 realizes real-time control of the airflow channel and the water flow channel through the signal output terminal. The signal input terminal of the control system circuit 19 receives signals from the array electrode probe 26, the temperature sensor 23, and the humidity sensor 17. The humidity sensor 17 is used to detect the air humidity of the current environment.

[0029] The airflow channel includes a miniature air pump 14 and an air meter 2. The miniature air pump 14 is connected to the air inlet 13 through a one-way air guide tube A1. The air inlet 13 is located outside the housing. The exhaust port of the miniature air pump 14 is connected to the air inlet of the air meter 2 through a one-way air guide tube B3. The exhaust port of the air meter 2 is connected to the air inlet 28 of the humidifier to form a one-way air path. The miniature air pump 14 draws air from the marine environment and the air flow is detected in real time by the air meter 2. The airflow enters the humidifier 12 through the one-way air path. The salt in the airflow dissolves in the pure water to form a mixture. The conductivity of the mixture is detected by an array electrode probe 26 and a control system circuit 19.

[0030] The water inlet 6 of the water flow channel is located outside the housing. An inlet valve 5 is installed between the inlet 6 and the flow metering micro-liquid pump 4. The outlet of the flow metering micro-liquid pump 4 is connected to the humidifier inlet 25 through a one-way guide pipe 7. The mixed liquid is discharged through the drain valve 8 connected to the humidifier drain port 27 and the drain port 9 located outside the housing. A drain valve 8 and a vent valve 11 are installed at the outlets of the humidifier drain port 27 and the humidifier vent port 21. The inlet valve 5, the drain valve 8, and the vent valve 11 are controlled by the control system circuit 19.

[0031] The control system circuit 19 includes a microcontroller. The first set of signal output terminals 15 of the microcontroller is connected to the micro air pump 14, the second set of signal output terminals is connected to the flow meter micro liquid pump 4, the third set of signal output terminals is connected to the control terminal of the air flow meter 2, the first set of signal input terminals 16 is connected to the signal output terminal of the air flow meter 2, the second set of signal input terminals 18 is connected to the signal output terminal of the humidity sensor 17, and the third set of signal input terminals 20 is connected to the sensor signal transmission interface 22 of the humidifier 12. The control system circuit 19 also includes a power supply circuit for powering the circuit components inside the housing.

[0032] This invention also discloses a method for detecting air salinity in a marine environment. Based on the aforementioned portable air salinity detection device for a marine environment, the air salinity detection system utilizes a flow metering micro-liquid pump 4 to draw pure water and deliver it to a humidifier 12. A micro-air pump 14 draws air from the marine environment to be tested and introduces it into the humidifier 12 through an airflow channel. The salt in the water vapor of the air mixes and dissolves thoroughly with the pure water in the humidifier 12 to form a mixture. A temperature sensor 23 performs temperature compensation for the conductivity, and an array electrode probe 26 detects the change in the conductivity of the mixture to obtain the salinity in the air. The specific steps are as follows:

[0033] Step 1. After initializing the control system circuit 19, complete the electrode sampling calibration and temperature sampling calibration. Use the flow meter micro liquid pump 4 to draw pure water into the humidifier 12 until the water volume reaches the preset value and then turn off the flow meter micro liquid pump 4. The water volume drawn by the flow meter micro liquid pump 4 is enough to completely submerge the temperature sensor 23 in the humidifier 12. The preset value of the water volume is adjusted according to the detection requirements during actual use to ensure that the water volume is not less than the water volume that completely submerges the temperature sensor 23.

[0034] Step 2. The control system circuit 19 drives the micro air pump 14 to draw the air to be measured into the airflow channel. When the airflow reaches the preset value, the micro air pump 14 is turned off. During the air extraction process, under the action of the stirring paddle 24, the salt in the water vapor of the air is fully dissolved in the pure water to form a mixture. During the dissolution process, the speed of the stirring paddle 24 is variable. The dissolution time is determined by the delay of the timer inside the microcontroller. The conductivity of the mixture is detected by the array electrode probe 26, and the temperature sensor 23 detects the temperature of the mixture. The temperature of the mixture is used in the conductivity calculation process. The airflow meter 2 and the microcontroller have bidirectional signal transmission. The microcontroller controls the start and stop of the airflow meter 2 through the output signal and receives the real-time airflow signal detected by the airflow meter 2.

[0035] Step 3. The microcontroller calculates the conductivity of the mixture by receiving the conductivity and temperature signals of the mixture, calculates the salinity in the air based on the conductivity and the volume of the extracted airflow, discharges the mixture through the drain port 9, and extracts pure water to rinse the humidifier 12 for the next test.

[0036] The conductivity method for measuring salinity is simple in principle, uses low-cost materials, has a fast measurement speed, and the measuring device is small and portable. With the help of a signal conditioning module, it can achieve a measurement accuracy of 1 μg / m³. Compared with the existing refractive index method, the conductivity method of this invention has three major advantages: a simpler measurement process, faster measurement speed, and lower device manufacturing cost. It is suitable for marine air salinity sensing devices in complex climatic environments.

[0037] The microcontroller of this invention uses an STM32F103RET6 chip, with an external 8MHz crystal oscillator providing a high-speed clock signal. It also includes a reset circuit and a power supply circuit. The microcontroller performs sampling signal conditioning, timing logic control of the sampling circuit, and conversion of sampled data. It also controls the micro air pump 14, the flow metering micro liquid pump 4, and the airflow meter 2, as well as the driving and logic control of the connected peripheral functional modules. The microcontroller of the control system circuit 19 sends a signal to control the micro air pump 14 to turn on. After receiving the signal, the micro air pump 14 responds to the microcontroller and begins to extract gas. At this time, the microcontroller sends a signal to the airflow meter 2. After receiving the signal, the airflow meter 2 starts its flow metering timer and simultaneously begins its flow metering function, transmitting the current gas flow rate back to the control system circuit 19 every 10ms. The control system circuit 19 calculates the volume of the extracted gas by using the current gas flow rate transmitted every 10ms, the flow metering time, and the cross-sectional area of ​​the gas path. The calculation formula is: Volume = Cross-sectional area × Flow rate × Time.

[0038] The micro air pump 14 employs a full H-bridge power amplifier circuit internally in its air pump drive module. Combined with the externally input pulse signal and closed-loop current sampling feedback circuit, it provides drive current to the internal electrode windings of the micro air pump 14. The micro air pump 14 uses a brushless motor drive and features a constant flow function. The airflow meter 2 uses a MEMS gas flow sensor chip solution, capable of monitoring a maximum air flow rate of 5 L / min. The constant current source module uses an LM334 adjustable constant current source chip. The flow-metering micro liquid pump 4 communicates with the microcontroller via I2C. The flow-metering micro liquid pump 4 calculates the total liquid volume pumped based on real-time flow rate and pump start-up time. Real-time control of liquid flow rate and volume is achieved; the temperature signal conditioning module adopts a circuit structure of front-end differential amplification and rear-end filtering output; the sine wave signal generation module adopts a circuit structure of front-end AD9850DDS chip and rear-end voltage follower circuit; the array electrode probe 26 is made of glass platinum; the electrode signal conditioning module adopts a front-end current-to-voltage conversion circuit, a mid-stage RMS-DC converter for AC-DC conversion, and a rear-end low-pass filter for filtering output; the airflow sampling module, electrode sampling module, and temperature sampling module all adopt ADS1220 analog-to-digital converter chip; the power management module consists of a linear voltage regulator chip.

[0039] The conductivity is obtained as follows: A constant current source is used to output a constant current, and the voltage across the temperature sensor 23 is detected to obtain the resistance change. The temperature change is obtained based on the resistance change of the temperature sensor 23, and the temperature measurement is completed. The voltage of the temperature sensor 23 is transmitted to the microcontroller through the temperature signal conditioning module and the temperature sampling module to obtain the digital value of the temperature. The microcontroller converts the digital value of the temperature into a temperature value as the temperature compensation for conductivity calculation. The current change of the mixture is detected by the array electrode probe 26. The current of the mixture is converted into a voltage signal through the electrode signal conditioning module and the RMS-DC conversion circuit and transmitted to the microcontroller. The microcontroller calculates the conductivity value G of the mixture and obtains the conductivity Q of the mixture by Q = G × K, where K is the electrode constant of the array electrode probe 26.

[0040] like Figure 4As shown, the microcontroller generates a PWM signal via an on-chip timer and inputs it to the air pump drive module. The air pump drive module outputs a current signal to drive the micro air pump 14. By adjusting the duty cycle of the PWM signal, the pumping speed of the micro air pump 14 is controlled. After the gas pumped by the micro air pump 14 flows through the airflow meter 2, the airflow meter 2 outputs an analog voltage signal of 0.5V-3V to the airflow sampling module. The airflow sampling module samples the voltage signal and converts it into a digital ADC value, which is sent to the microcontroller via the I2C protocol. The microcontroller calculates the airflow rate by the digital ADC value of the airflow, and then calculates the total volume of gas pumped based on the pumping time and the cross-sectional area of ​​the air path. In the figure, the constant current source outputs a 1mA current to drive the temperature sensor 23. In this embodiment, the temperature sensor 23 is a PT1000. The internal resistance of the PT1000 changes with temperature, and is 1000Ω at 0℃, with a temperature coefficient of (3.85±0).05) Ω / ℃, in this embodiment, the constant current source outputs 1mA. According to Ohm's law, the voltage across PT1000 is proportional to its resistance. By sampling the voltage across PT1000, the change in resistance can be calculated, and the temperature change can be obtained through calculation, thus realizing the temperature measurement function. The voltage across PT1000 is input differentially to the temperature signal conditioning module for pre-stage differential amplification and post-stage filtering. The temperature sampling module samples the differential voltage signal output by the temperature signal conditioning module to obtain the digital ADC value of the temperature, which is then sent to the microcontroller via the I2C protocol. The microcontroller calculates the temperature value after processing the digital ADC value. In the figure, the microcontroller controls the sine wave signal generation module to output a frequency of 10KHz and an amplitude of 10kHz via the SPI protocol. The sinusoidal signal Vdrive is transmitted to the array electrode probe 26, which is immersed in the mixture inside the humidifier 12. The mixture dissolves salts from the water vapor in the air being tested, causing a change in its conductivity, i.e., a change in the current flowing through it. This current change is transmitted through the array electrode probe 26 to the electrode signal conditioning module. The pre-amplifier current-to-voltage conversion circuit of the electrode signal conditioning module uses an operational amplifier to form an inverting amplifier circuit. The feedback resistor Rf is switched by an analog switch. One end of the array electrode probe 26 is connected to the drive signal generated by the sinusoidal signal generation module, and the other end is connected to the inverting input of the operational amplifier. The feedback resistor Rf converts the current Iac flowing through the mixture inside the humidifier 12 into an analog voltage signal Vac: Vac = Iac×Rf, where both voltage signal Vac and current Iac are AC signals, are converted from AC to DC by an RMS-DC converter circuit. Finally, a low-pass filter outputs an analog DC voltage signal Vdc. The microcontroller reads the value of Vdc through the electrode sampling module and calculates the current flowing through the mixture using I=Vdc / (Gain×Rf), where Gain is the overall gain of the RMS-DC converter and the low-pass filter circuit. The resistance value R is obtained using R=Vdrive / I, and the conductivity G of the mixture is obtained using G=1 / R. Finally, the conductivity Q of the mixture is obtained using Q=G×K, where K is the electrode constant of the array electrode probe 26. Since conductivity is highly dependent on temperature... Based on the temperature T of the mixed solution collected by the PT1000 temperature sensor, the final conductivity Q with temperature compensation is obtained using the formula Q_25=Q / (1+a(T-25)), where a is a temperature coefficient related to the type of salt ions, and a value of 0.019 or 0.021. When testing in areas other than marine environments, a value of 0.019 is used, and when testing in high-salinity marine environments, a value of 0.021 is used. 25 represents the ambient temperature of 25℃, which is a constant. The ambient temperature of 25℃ chosen for temperature compensation is a common reference value in the electrical and chemical fields. Then, the conductivity Q is substituted into the dimensionless practical salinity standard calculation formula to obtain the salinity value of the mixed solution. Practical salinity standard calculation formula: Salinity = Conductivity Q × 0.64~0.70. Since the salt in the mixture is entirely obtained by dissolving the extracted gas, the salinity value per unit volume of the extracted gas can be calculated based on the total volume of the extracted gas.

[0041] The above description is merely a preferred embodiment of the present invention. The scope of protection of the present invention is not limited to the above embodiments. All technical solutions falling within the scope of the present invention's concept are within the scope of protection of the present invention. It should be noted that for those skilled in the art, any improvements and modifications made without departing from the principles of the present invention should also be considered within the scope of protection of the present invention.

Claims

1. A method for detecting salinity in marine ambient air, based on a portable marine ambient air salinity detection device, characterized in that: The portable marine environment air salinity detection device includes a housing and an air salinity detection system placed inside the housing. A humidity sensor (17) is installed on the outer wall of the housing. The air salinity detection system includes a control system circuit (19), an airflow channel, and a water flow channel. The airflow channel and the water flow channel are merged in a humidifier (12) for detecting salinity. Various salt ions to be measured in the water vapor in the air are dissolved in pure water. The salinity in the air is obtained by measuring the conductivity of the electrodes immersed in the pure water and obtaining the change in conductivity of the mixture. The humidifier (12) includes a temperature sensor (23) and several array electrode probes (26) installed inside the humidifier (12). The signal output terminals of the array electrode probes (26) and the temperature sensor (23) are connected to the third set of signal input terminals of the control system circuit (19) through a sensor signal transmission interface (22). (20); The humidifier (12) also includes a humidifier air inlet (28), a humidifier water inlet (25), a humidifier exhaust port (21) and a humidifier drain port (27). The humidifier exhaust port (21) and the humidifier water inlet (25) are located on the same side of the humidifier (12), and the humidifier air inlet (28) and the humidifier drain port (27) are located on the same side of the humidifier (12). The horizontal position of the humidifier exhaust port (21) and the humidifier water inlet (25) is higher than that of the humidifier air inlet (28) and the humidifier drain port (27). Several stirring paddles (24) are provided at the bottom of the inner wall of the humidifier (12). The control system circuit (19) realizes real-time control of the airflow channel and the water flow channel through the signal output terminal. The signal input terminal of the control system circuit (19) receives the signals of the array electrode probe (26), the temperature sensor (23) and the humidity sensor (17). The conductivity obtained using the portable marine ambient air salinity detection device is as follows: Using a constant current source to output constant current, the voltage across the temperature sensor (23) is detected to obtain the resistance change. The temperature change is obtained based on the resistance change of the temperature sensor (23), and the temperature measurement is completed. The voltage of the temperature sensor (23) is transmitted to the microcontroller through the temperature signal conditioning module and the temperature sampling module to obtain the digital value of the temperature. The microcontroller converts the digital value of the temperature into a temperature value as temperature compensation for conductivity calculation. The current change of the mixture is detected by the array electrode probe (26). The current of the mixture is converted into a voltage signal through the electrode signal conditioning module and the RMS-DC conversion circuit and transmitted to the microcontroller. The microcontroller calculates and obtains the conductivity value G of the mixture. The conductivity Q of the mixture is obtained by Q=G×K, where K is the electrode constant of the array electrode probe (26). The air salinity detection system uses a flow meter-type micro liquid pump (4) to draw pure water and deliver it to the humidifier (12). A micro air pump (14) draws the air to be tested from the marine environment and enters the humidifier (12) through the airflow channel. The salt in the water vapor in the air is fully mixed and dissolved with the pure water in the humidifier (12) to form a mixture. The conductivity is compensated by a temperature sensor (23). The array electrode probe (26) detects the change in the conductivity of the mixture to obtain the salinity in the air. The specific steps are as follows: Step 1. After initialization of the control system circuit (19), electrode sampling calibration and temperature sampling calibration are completed. Pure water is drawn into the humidifier (12) by the flow meter micro liquid pump (4) until the water volume reaches the preset value and the flow meter micro liquid pump (4) is turned off. The water volume drawn by the flow meter micro liquid pump (4) completely submerges the temperature sensor (23) in the humidifier (12). Step 2. The control system circuit (19) drives the micro air pump (14) to draw the air to be tested into the airflow channel. When the air flow reaches the preset value, the micro air pump (14) is turned off. During the air extraction process, under the action of the stirring paddle (24), the salt in the water vapor in the air is fully dissolved in the pure water to form a mixture. The conductivity of the mixture is detected by the array electrode probe (26), and the temperature sensor (23) detects the temperature of the mixture. Step 3. The microcontroller calculates the conductivity of the mixture by receiving the conductivity and temperature signals of the mixture, calculates the salinity in the air based on the conductivity and the volume of the extracted airflow, discharges the mixture through the drain (9) and extracts pure water to rinse the humidifier (12) for the next test.

2. The method for detecting marine ambient air salinity according to claim 1, characterized in that: The airflow channel includes a micro air pump (14) and an air meter (2). The micro air pump (14) is connected to the air inlet (13) through a one-way air guide tube A (1). The air inlet (13) is located outside the housing. The exhaust port of the micro air pump (14) is connected to the air inlet of the air meter (2) through a one-way air guide tube B (3). The exhaust port of the air meter (2) is connected to the air inlet (28) of the humidifier to form a one-way air path. The micro air pump (14) draws air from the marine environment and the air flow is detected in real time by the air meter (2). The airflow enters the humidifier (12) through the one-way air path. The salt in the airflow dissolves in the pure water to form a mixture. The conductivity of the mixture is detected by an array electrode probe (26) and a control system circuit (19).

3. The method for detecting marine ambient air salinity according to claim 1, characterized in that: The inlet (6) of the water flow channel is located outside the housing. An inlet valve (5) is provided between the inlet (6) and the flow meter micro liquid pump (4). The outlet of the flow meter micro liquid pump (4) is connected to the humidifier inlet (25) through a one-way guide pipe (7). The mixed liquid is discharged through the drain valve (8) connected to the humidifier drain (27) and the drain outlet (9) located outside the housing.

4. The method for detecting marine ambient air salinity according to claim 1, characterized in that: The control system circuit (19) includes a microcontroller. The first set of signal output terminals (15) of the microcontroller is connected to a micro air pump (14), the second set of signal output terminals is connected to a flow meter micro liquid pump (4), the third set of signal output terminals is connected to the control terminal of the air flow meter (2), the first set of signal input terminals (16) is connected to the signal output terminal of the air flow meter (2), the second set of signal input terminals (18) is connected to the signal output terminal of the humidity sensor (17), and the third set of signal input terminals (20) is connected to the sensor signal transmission interface (22) of the humidifier (12). The control system circuit (19) also includes a power supply circuit for powering the circuit components inside the housing.

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