CN102445473A - Method and system for monitoring and analyzing air - Google Patents

Abstract

The invention discloses an air monitoring and analysis method, comprising the following steps: collecting on-site gas, and performing pressurization on the collected on-site gas, wherein the pressure applied to the on-site gas is equal to or lower than the preset The pressure threshold; the pressure-treated gas is heated to a preset temperature threshold; the sensor group is used to detect the temperature-raised gas to obtain the parameters of various types of gases in the temperature-raised gas, and generate Multiple detection signals corresponding to the parameters of the various types of gases; analyzing and processing the multiple detection signals to obtain the gas conditions of the on-site gas. The invention also discloses an air monitoring and analyzing system. The invention effectively improves signal stability and resolution, lowers the minimum detection threshold of the entire air monitoring and analysis system by an order of magnitude, and fully meets the technical requirements of air quality monitoring.

Description

Air monitoring and analysis method and system

technical field

The invention relates to the technical field of environmental monitoring, in particular to an air monitoring and analysis method and system.

Background technique

Traditional instruments and devices used in environmental monitoring include the following situations:

(1) An environmental monitoring system consisting of one or more single gas analyzers. The system has the advantages that the monitoring parameters can be increased or decreased, and the monitoring accuracy is high, stable and reliable.

However, the system has the disadvantages of large volume, high power consumption, and inability to move. At the same time, the high cost of the system and the high maintenance cost make the system only suitable for monitoring in key areas of large cities, which is not conducive to promotion.

(2) A regional environmental monitoring method consisting of a group of monitoring systems and multiple gas samplers or particle samplers. In this method, the sampling area is determined by the monitoring and sampling staff, and the gas samples and particulate matter samples from different locations are sampled and returned to the laboratory for sample analysis. This method has the advantages of wide sampling range, many kinds of samples to be analyzed, and cost saving.

However, there are disadvantages that the samples analyzed are not real-time data, which increases the workload, and does not meet the requirements of continuous monitoring of pollution sources.

(3) The gas monitoring instrument using the electrochemical principle is used for environmental monitoring. This method has the advantages of small size, low power consumption, mobility, and continuous monitoring.

However, at present, there is no system test report from an authoritative organization that can analyze trace concentrations (1×10-9) of sensors based on this principle. In the known applications of environmental monitoring using electrochemical methods, constant temperature, constant humidity, constant The method of flow rate or the method of temperature and humidity compensation, this method can only be detected in the concentration range above the resolution of the sensor itself, and the stability of the data is guaranteed. Therefore, this principle sensor has the disadvantage that the detection resolution cannot meet the requirements of air quality monitoring. Currently, the low-concentration end data displayed by the instrument device manufactured with this sensor is calculated based on mid-to-high-end data and cannot represent real data. At the same time, because the electrochemical sensor itself has the characteristics of mutual interference between gases, there will be a large systematic error in the data obtained without the help of hardware design and software reasonable algorithm.

Contents of the invention

The purpose of the present invention is to solve at least one of the above-mentioned technical drawbacks.

To this end, the embodiment of the first aspect of the present invention provides an air monitoring and analysis method, including the following steps: collecting on-site gas, and performing pressurization on the collected on-site gas, wherein, applying to the on-site The pressure of the gas is equal to or lower than the preset pressure threshold;

The pressurized gas is heated up to the preset temperature threshold,

Using a sensor group to detect the gas after the temperature rise treatment to obtain the parameters of multiple types of gases in the gas after the temperature rise treatment, and generate multiple detection signals corresponding to the parameters of the multiple types of gases;

Analyzing and processing the multiple detection signals to obtain the gas condition of the on-site gas.

According to the air monitoring and analysis method of the embodiment of the present invention, the gas sample is collected through the gas sampling pump, and the gas is pressurized and heated through the pre-processing unit, thereby increasing the gas activity and unit density, and converting the gas concentration signal The electrical signal is transmitted to the acquisition and control unit of the single-board computer, and after signal processing, the result is displayed, stored, and transmitted. The air monitoring and analysis system of the embodiment of the present invention improves the signal sensitivity of the same gas sensor by 4-10 times in the detection, effectively improves the signal stability, improves the resolution, and makes the entire air monitoring and analysis system the lowest detection The threshold is reduced by an order of magnitude, fully meeting the technical requirements of air quality monitoring.

The embodiment of the second aspect of the present invention provides an air monitoring and analysis system, including a collection module for collecting on-site gas; a pressurization module for pressurizing the collected on-site gas, wherein the The pressure of the on-site gas is equal to or lower than the preset pressure threshold; the heating module is used to raise the temperature of the pressurized gas to the preset temperature threshold; the detection module is used to detect the heated gas to obtain The parameters of various types of gases in the gas after the temperature rise treatment, and generate multi-channel detection signals corresponding to the parameters of the various types of gases; the control module is used to analyze and process the multi-channel detection signals, and obtain the Describe the gas state of the on-site gas.

According to the air monitoring and analysis system of the embodiment of the present invention, the gas sample is collected through the gas sampling pump, and the gas is pressurized and heated through the pre-processing unit, thereby increasing the gas activity and unit density, and converting the gas concentration signal The electrical signal is transmitted to the acquisition and control unit of the single-board computer, and after signal processing, the result is displayed, stored, and transmitted. The air monitoring and analysis system of the embodiment of the present invention improves the signal sensitivity of the same gas sensor by 4-10 times in the detection, effectively improves the signal stability, improves the resolution, and makes the entire air monitoring and analysis system the lowest detection The threshold is reduced by an order of magnitude, fully meeting the technical requirements of air quality monitoring. Moreover, in the process of gas detection with cross interference, the factors affected by interfering gases are effectively eliminated.

Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention.

Description of drawings

The above and/or additional aspects and advantages of the present invention will become apparent and easy to understand from the following description of the embodiments in conjunction with the accompanying drawings, wherein:

Fig. 1 is the flowchart of the air monitoring and analyzing method according to one embodiment of the present invention;

Fig. 2 is the flowchart of the air monitoring and analysis method according to another embodiment of the present invention;

Fig. 3 is a structural diagram of an air monitoring and analysis system according to an embodiment of the present invention;

4 is a structural diagram of an air monitoring and analysis system according to another embodiment of the present invention;

5 is a structural diagram of a control module according to an embodiment of the present invention; and

Fig. 6 is a structural diagram of an air monitoring and analysis system according to another embodiment of the present invention.

Detailed ways

Embodiments of the present invention are described in detail below, examples of which are shown in the drawings, wherein the same or similar reference numerals designate the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by referring to the figures are exemplary only for explaining the present invention and should not be construed as limiting the present invention.

These and other aspects of embodiments of the invention will become apparent with reference to the following description and drawings. In these descriptions and drawings, some specific implementations of the embodiments of the present invention are specifically disclosed to represent some ways of implementing the principles of the embodiments of the present invention, but it should be understood that the scope of the embodiments of the present invention is not limited by this limit. On the contrary, the embodiments of the present invention include all changes, modifications and equivalents coming within the spirit and scope of the appended claims.

In environmental monitoring, electrochemical sensors are usually used to monitor gas parameters in the environment. The signal generated by the electrochemical sensor is a current source, and the signal sensitivity is at the level of nA/ppb. Such a weak signal is extremely susceptible to environmental interference and will vary with sensor temperature. Specifically, the instantaneous signal i(A) of a sensor during the entire ventilation period is the differential of the total transferred charge Q(C) during the entire response period, that is,

$\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; wxya</span>}}{\mathrm{<span\; class="notranslate">\; dt</span>}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; )</span>$

The total transfer charge Q(C) during the reaction is related to the number of molecules N(mol) participating in the reaction per unit time and the molecular activity A(mol/mol). Under the premise of constant temperature and constant electrolyte, the gas reactivity A degree is fixed. Therefore, the total number Q of charges generated in a complete reaction cycle of a certain fixed activity A is:

$\mathrm{<span\; class="notranslate">\; Q</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; A</span>}{<span\; class="notranslate">\; \&Integral;</span>}_{\mathrm{<span\; class="notranslate">\; 0</span>}}^{\mathrm{<span\; class="notranslate">\; t</span>}\mathrm{<span\; class="notranslate">\; 100</span>}}\mathrm{<span\; class="notranslate">\; N</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; )</span>\mathrm{<span\; class="notranslate">\; dt</span>}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; )</span>$

Among them, t100 is the entire reaction time period, A is the gas reaction activity, and N(t) is the molecular function of the instant time participating in the reaction.

From formula (1) and formula (2), it can be found that the sensor signal sensitivity is related to the number of gas molecules that the sensor electrolyte is exposed to per unit time. According to the theory of molecular motion, the higher the concentration of molecules, the greater the pressure, and the higher the temperature, the greater the chance of electrolyte contact. However, the excessive increase of pressure and temperature will cause damage to the life of the sensor, and if the increase is too large, it will even cause permanent failure of the sensor. Based on the above analysis, the present invention provides an air monitoring and analysis method that reasonably pressurizes and raises the temperature of the gas. The method reasonably pressurizes and raises the temperature of the gas on site, so that the gas molecules accumulate in the sensor diffusion port in a short time , on the premise of not damaging the sensor, the sensitivity of the sensor is greatly increased, and the sensor is provided with sufficient recovery time, so as to achieve the purpose of working stably within the validity period.

The air monitoring and analysis method according to the embodiment of the present invention will be described below with reference to FIG. 1 .

As shown in Figure 1, the air monitoring and analysis method of the embodiment of the present invention comprises the following steps:

Step S101, collect on-site gas, and pressurize the collected on-site gas. Wherein, the pressure applied to the on-site gas is equal to or lower than a preset pressure threshold.

In an embodiment of the present invention, the preset pressure threshold is lower than or equal to the safety pressure threshold of each sensor in the sensor group. The safe pressure threshold of a sensor is the highest pressure that the sensor can withstand.

According to the theory of gas molecules, increasing the pressure will increase the number of gas molecules per unit volume, so that the number of gas molecules entering the detection sensitive element (such as a sensor) will increase, which in turn will increase the sensitivity value. However, the sensor has a certain limit on the pressure, and excessive pressure will damage the sensor. The functional relationship between the pressure and the sensitivity of the sensor is A=f(p), and the gas concentration at the pressure can be calculated by calculating the sensitivity at a specific pressure. By adopting the method of pressurizing the gas, the sensitivity of the sensor can be increased to 2-3 times of the original within the pressure range that can withstand.

In step S102, the temperature of the pressurized gas is raised to a preset temperature threshold. Wherein, the preset temperature threshold is lower than or equal to the safe temperature threshold of each sensor in the sensor group. The safe temperature threshold of a sensor refers to the maximum temperature allowed by the sensor. In one embodiment of the present invention, the preset temperature threshold may be 5 degrees lower than the safe temperature threshold of the sensor.

According to the theory of gas thermodynamics, increasing the gas temperature will increase the movement of gas molecules, and also increase the reactivity of the gas sensor. Within the allowable temperature range of the sensor, sending the gas to the constant temperature gas chamber whose temperature is the preset temperature threshold can increase the temperature of the gas, thereby increasing the reactivity of the gas sensor, and allowing the sensor to work in a constant temperature environment can not only improve the sensitivity, but also Ensure the working stability of the sensor. By using the method of raising the temperature of the gas, the sensitivity can be increased to more than 2 times of the original.

It can be seen from the above that by combining the two methods of heating and pressurizing the gas, the sensitivity of the sensor can be increased to 4-6 times of the original.

Step S103 , using the sensor group to detect the gas after the temperature rise treatment to obtain parameters of various types of gases in the temperature increase treated gas, and generate multiple detection signals corresponding to the parameters of the various types of gases.

The sensor set includes one or more sensors, each corresponding to detecting a different type of gas. Since there are many different types of gases in the field gas, the monitoring of different types of gases can be realized by using different sensors.

The sensor group monitors the gas whose temperature rises to a preset temperature threshold, and obtains parameters of various types of gas. Wherein, the parameters of various types of gases include: concentration of various types of gases, activity of various types of gases, and concentration of inhalable particulate matter.

Specifically, the concentration of inhalable particulate matter can be connected to an inhalable particulate matter analysis instrument through a hardware interface, and the inhalable particulate matter data will be displayed in the monitoring system after corresponding analysis and processing, and the monitoring data will be transmitted to the environmental monitoring station, so that users can timely grasp the The concentration of respirable particulate matter in the field environment.

The concentration and activity of many types of gases can be monitored by sensors. For each sensor, the parameters of the gas it detects include the concentration and activity of the gas detected by the sensor. Thus, each sensor generates one detection signal.

In an embodiment of the present invention, electrochemical sensors are used to detect gas parameters. The use of electrochemical sensors to detect pressurized and heated on-site gases is not only suitable for the monitoring of conventional gas pollutants, such as SO2, NO2, CO, H2S, etc., but also suitable for unconventional gas pollution emitted by factories and enterprises. emissions, such as: halogen gases, halide gases, TVOC (Total Volatile Organic Compounds, total volatile organic compounds), etc.

Due to the broad-spectrum or gas cross-interference characteristics of electrochemical sensors, gases with similar chemical properties will have a response signal to the sensor. Therefore, in the process of detecting the mixed gas with cross-interference gas, some sensors have a common reaction phenomenon in the process of monitoring several gases. Therefore, the data obtained without reasonable and efficient data processing is incorrect. Since the sensor's own signal is very weak, if it is affected by environmental factors, such as large changes in temperature and humidity and electromagnetic interference, the signal will be severely distorted, and it is difficult or even difficult to compensate. Therefore, in the embodiment of the present invention, anti-gas cross-interference processing is performed on the multi-channel detection signals generated by the sensor group to generate multi-channel anti-gas cross-interference detection signals.

Two types of sensors S1 and S2 are taken as examples for description below. Among them, the sensor S1 and the sensor S2 detect the gas G1 and the gas G2. The sensitivities of sensors S1 and S2 to gases G1 and G2 are A11, A12, A21 and A22, respectively. During the detection process, the total semaphore of S1 is D1, and the total semaphore of S2 is D2. In the test results, the gas concentration of G1 is C1, and the gas concentration of G2 is C2, and the corresponding formula is as follows:

A11*C1+A12*C2＝D1

A21*C1+A22*C2＝D2

According to the determinant solution,

$\mathrm{<span\; class="notranslate">\; C</span>}\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; =</span>\frac{\left|\begin{array}{cc}\mathrm{<span\; class="notranslate">\; D.</span>}\mathrm{<span\; class="notranslate">\; 1</span>}& \mathrm{<span\; class="notranslate">\; A</span>}\mathrm{<span\; class="notranslate">\; 12</span>}\\ \mathrm{<span\; class="notranslate">\; D.</span>}\mathrm{<span\; class="notranslate">\; 2</span>}& \mathrm{<span\; class="notranslate">\; A</span>}\mathrm{<span\; class="notranslate">\; twenty\; two</span>}\end{array}\right|}{\left|\begin{array}{cc}\mathrm{<span\; class="notranslate">\; A</span>}\mathrm{<span\; class="notranslate">\; 11</span>}& \mathrm{<span\; class="notranslate">\; A</span>}\mathrm{<span\; class="notranslate">\; 12</span>}\\ \mathrm{<span\; class="notranslate">\; A</span>}\mathrm{<span\; class="notranslate">\; twenty\; one</span>}& \mathrm{<span\; class="notranslate">\; A</span>}\mathrm{<span\; class="notranslate">\; twenty\; two</span>}\end{array}\right|}<span\; class="notranslate">\; ,</span>$ $\mathrm{<span\; class="notranslate">\; C</span>}\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; =</span>\frac{\left|\begin{array}{cc}\mathrm{<span\; class="notranslate">\; A</span>}\mathrm{<span\; class="notranslate">\; 11</span>}& \mathrm{<span\; class="notranslate">\; D.</span>}\mathrm{<span\; class="notranslate">\; 1</span>}\\ \mathrm{<span\; class="notranslate">\; A</span>}\mathrm{<span\; class="notranslate">\; 12</span>}& \mathrm{<span\; class="notranslate">\; D.</span>}\mathrm{<span\; class="notranslate">\; 2</span>}\end{array}\right|}{\left|\begin{array}{cc}\mathrm{<span\; class="notranslate">\; A</span>}\mathrm{<span\; class="notranslate">\; 11</span>}& \mathrm{<span\; class="notranslate">\; A</span>}\mathrm{<span\; class="notranslate">\; 12</span>}\\ \mathrm{<span\; class="notranslate">\; A</span>}\mathrm{<span\; class="notranslate">\; twenty\; one</span>}& \mathrm{<span\; class="notranslate">\; A</span>}\mathrm{<span\; class="notranslate">\; twenty\; two</span>}\end{array}\right|}$

Using the determinant calculation method can avoid systematic errors. Moreover, the above algorithm is suitable for the following three situations

(1) There are any two or more of gaseous pollutants SO ₂ , NO ₂ , H ₂ , and O ₃ ;

(2) Any two or more of gas pollutants CO, H ₂ S, and H ₂ are present;

(3) Any two or more of gas pollutants HF, HCL, H ₂ S, and CL ₂ are present.

The mutual interference between H ₂ S, NO ₂ and SO ₂ and the mutual interference between H ₂ S and CO can be avoided by performing anti-gas cross-interference processing on the multi-channel detection signals.

In one embodiment of the present invention, the electromagnetic interference between multiple channels of anti-gas cross-interference detection signals can be reduced by means of mode suppression and electromagnetic shielding.

Step S104, analyzing and processing the multi-channel detection signals to obtain the gas condition of the on-site gas.

The parameters of multiple types of gases in the multi-channel detection signals generated in step S103 are analyzed and processed, so that the gas conditions of the on-site gas can be obtained. The gas statistical curve is generated according to the obtained gas condition of the on-site gas, and the gas statistical curve is displayed to the monitoring personnel, so that the monitoring personnel can grasp the status of the on-site gas in time. Wherein, the gas statistical curve is used to indicate indicators of various gases in the on-site gas within different time periods.

By looking at the gas statistical curve, one or more gas indexes among various types of gases in the air on site are compared with the preset indexes corresponding to the gas. When the index of one or more of the various types of gases in the on-site air exceeds the preset index corresponding to the gas, an alarm signal is sent, thereby prompting the monitoring personnel that the current on-site air quality is not up to standard. After receiving the alarm signal, the monitoring personnel can make corresponding air purification treatment in time.

In the embodiment of the present invention, a series of preparatory actions need to be performed before step S101 is executed. Specifically, as shown in Figure 2,

Step S201, power on and start.

Step S202, start the control module, and start other functions by the control module. For example: start the working status monitoring function, start the gas pressurization and temperature rise function and start the sensor, etc.

Step S203, monitoring the working status of each functional unit, and judging whether each functional unit works normally. If each functional unit is normal, execute step S207, otherwise execute step S204.

Step S204, issuing an alarm.

Step S205, judging whether the working conditions are met. If so, execute step S207; otherwise, repeat step S205 until the working condition is satisfied. Wherein, the working condition may be whether the whole machine is preheated, in other words, each functional module satisfies its own working condition.

Step S206, judging whether the sensor is stable. If yes, execute step S207, otherwise repeat step S206 until the sensor works stably.

Step S207, start the monitoring program and collect data.

Step S208, analyzing and calculating the collected data, storing and displaying the above collected data, forming a curve and transmitting the above data, etc. When abnormal data is detected, an alarm signal is sent.

It can be understood that the functions in step S101 to step S104 in FIG. 1 are executed after step S206, wherein step S207 and step S208 are an overview of the functions in step S101 to step S104.

According to the air monitoring and analysis method of the embodiment of the present invention, the gas sample is collected through the gas sampling pump, and the gas is pressurized and heated through the pre-processing unit, thereby increasing the gas activity and unit density, and converting the gas concentration signal The electrical signal is transmitted to the acquisition and control unit of the single-board computer, and after signal processing, the result is displayed, stored, and transmitted. The air monitoring and analysis system of the embodiment of the present invention improves the signal sensitivity of the same gas sensor by 4-10 times in the detection, effectively improves the signal stability, improves the resolution, and makes the entire air monitoring and analysis system the lowest detection The threshold is reduced by an order of magnitude, fully meeting the technical requirements of air quality monitoring. Moreover, in the process of gas detection with cross interference, the factors affected by interfering gases are effectively eliminated.

An air monitoring and analysis system according to an embodiment of the present invention will be described below with reference to FIGS. 3 and 4 .

As shown in Figure 3, the air monitoring and analysis system of the embodiment of the present invention includes an acquisition module 310, a pressurization module 320, a heating module 330, a detection module 340 and a control module 350, wherein the acquisition module 310 is used to collect on-site gas; The pressure module 320 is used to pressurize the collected on-site gas, wherein the pressure applied to the on-site gas is equal to or lower than the preset pressure threshold; the temperature rise module 330 is used to raise the temperature of the pressurized gas to the preset pressure. Temperature threshold; the detection module 340 is used to detect the gas after the temperature rise treatment to obtain the parameters of multiple types of gases in the temperature rise treated gas, and generate multiple detection signals corresponding to the parameters of multiple types of gases, wherein The detection module 340 may be a sensor group; the control module 350 is used to analyze and process multiple detection signals to obtain the gas state of the on-site gas.

In one embodiment of the present invention, the pressurization module 320 may be a pressurized air pump.

In one embodiment of the present invention, the temperature raising module 330 may be a constant temperature box. The safe temperature threshold of a sensor refers to the maximum temperature allowed by the sensor. In one embodiment of the present invention, the preset temperature threshold may be 5 degrees lower than the safe temperature threshold of the sensor.

According to the theory of gas thermodynamics, increasing the gas temperature will increase the movement of gas molecules, and also increase the reactivity of the gas sensor. Within the allowable temperature range of the sensor, sending the gas to the constant temperature gas chamber whose temperature is the preset temperature threshold can increase the temperature of the gas, thereby increasing the reactivity of the gas sensor, and allowing the sensor to work in a constant temperature environment can not only improve the sensitivity, but also Ensure the working stability of the sensor. By using the method of raising the temperature of the gas, the sensitivity can be increased to more than 2 times of the original.

It can be seen from the above that by combining the two methods of heating and pressurizing the gas, the sensitivity of the sensor can be increased to 4-6 times of the original.

In an embodiment of the present invention, the detection module 340 may be a sensor group. Wherein, the sensor group includes at least one sensor. Each sensor is used to detect a parameter of a type of gas and generate a detection signal corresponding to the parameter of the type of gas. Since there are many different types of gases in the field gas, the monitoring of different types of gases can be realized by using different sensors. Wherein, the parameters of the gas include the concentration of the gas and the density of the gas. The sensor group monitors the gas whose temperature rises to a preset temperature threshold, and obtains parameters of various types of gas. Wherein, the parameters of the various types of gases include: the concentration of the various types of gases and the activity of the various types of gases. Specifically, for each sensor, the parameters of the gas detected by it include the concentration and activity of the gas detected by the sensor. Thus, each sensor generates one detection signal.

In an embodiment of the present invention, the preset pressure threshold is lower than or equal to the safety pressure threshold of each sensor in the sensor group. The safe pressure threshold of a sensor is the highest pressure that the sensor can withstand.

According to the theory of gas molecules, increasing the pressure will increase the number of gas molecules per unit volume, so that the number of gas molecules entering the detection sensitive element (such as a sensor) will increase, which in turn will increase the sensitivity value. However, the sensor has a certain limit on the pressure, and excessive pressure will damage the sensor. The functional relationship between the pressure and the sensitivity of the sensor is A=f(p), and the gas concentration at the pressure can be calculated by calculating the sensitivity at a specific pressure. By adopting the method of pressurizing the gas, the sensitivity of the sensor can be increased to 2-3 times of the original within the pressure range that can withstand.

In an embodiment of the present invention, electrochemical sensors are used to detect gas parameters. The use of electrochemical sensors to detect pressurized and heated on-site gases is not only suitable for the monitoring of conventional gas pollutants, such as SO2, NO2, CO, H2S, etc., but also suitable for unconventional gas pollution emitted by factories and enterprises. emissions, such as: halogen gases, halide gases, TVOC (Total Volatile Organic Compounds, total volatile organic compounds), etc.

Due to the broad-spectrum or gas cross-interference characteristics of electrochemical sensors, gases with similar chemical properties will have a response signal to the sensor. Therefore, in the process of detecting the mixed gas with cross-interference gas, some sensors have a common reaction phenomenon in the process of monitoring several gases. Therefore, the data obtained without reasonable and efficient data processing is incorrect. Since the sensor's own signal is very weak, if it is affected by environmental factors, such as large changes in temperature and humidity and electromagnetic interference, the signal will be severely distorted, and it is difficult or even difficult to compensate. In the embodiment of the present invention, the air monitoring and analysis system of the embodiment of the present invention also includes an anti-gas cross-interference processing module 360, which is connected to the heating module 330 and the detection module 340 respectively, and is used to raise the temperature of the gas processed by the heating module 330. Perform anti-gas cross-interference processing to generate multi-channel anti-gas cross-interference detection signals.

Two types of sensors S1 and S2 are taken as examples for description below. Among them, the sensor S1 and the sensor S2 detect the gas G1 and the gas G2. The sensitivities of sensors S1 and S2 to gases G1 and G2 are A11, A12, A21 and A22, respectively. During the detection process, the total semaphore of S1 is D1, and the total semaphore of S2 is D2. In the test results, the gas concentration of G1 is C1, and the gas concentration of G2 is C2, and the corresponding formula is as follows:

A11*C1+A12*C2＝D1

A21*C1+A22*C2＝D2

According to the determinant solution,

$\mathrm{<span\; class="notranslate">\; C</span>}\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; =</span>\frac{\left|\begin{array}{cc}\mathrm{<span\; class="notranslate">\; D.</span>}\mathrm{<span\; class="notranslate">\; 1</span>}& \mathrm{<span\; class="notranslate">\; A</span>}\mathrm{<span\; class="notranslate">\; 12</span>}\\ \mathrm{<span\; class="notranslate">\; D.</span>}\mathrm{<span\; class="notranslate">\; 2</span>}& \mathrm{<span\; class="notranslate">\; A</span>}\mathrm{<span\; class="notranslate">\; twenty\; two</span>}\end{array}\right|}{\left|\begin{array}{cc}\mathrm{<span\; class="notranslate">\; A</span>}\mathrm{<span\; class="notranslate">\; 11</span>}& \mathrm{<span\; class="notranslate">\; A</span>}\mathrm{<span\; class="notranslate">\; 12</span>}\\ \mathrm{<span\; class="notranslate">\; A</span>}\mathrm{<span\; class="notranslate">\; twenty\; one</span>}& \mathrm{<span\; class="notranslate">\; A</span>}\mathrm{<span\; class="notranslate">\; twenty\; two</span>}\end{array}\right|}<span\; class="notranslate">\; ,</span>$ $\mathrm{<span\; class="notranslate">\; C</span>}\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; =</span>\frac{\left|\begin{array}{cc}\mathrm{<span\; class="notranslate">\; A</span>}\mathrm{<span\; class="notranslate">\; 11</span>}& \mathrm{<span\; class="notranslate">\; D.</span>}\mathrm{<span\; class="notranslate">\; 1</span>}\\ \mathrm{<span\; class="notranslate">\; A</span>}\mathrm{<span\; class="notranslate">\; 12</span>}& \mathrm{<span\; class="notranslate">\; D.</span>}\mathrm{<span\; class="notranslate">\; 2</span>}\end{array}\right|}{\left|\begin{array}{cc}\mathrm{<span\; class="notranslate">\; A</span>}\mathrm{<span\; class="notranslate">\; 11</span>}& \mathrm{<span\; class="notranslate">\; A</span>}\mathrm{<span\; class="notranslate">\; 12</span>}\\ \mathrm{<span\; class="notranslate">\; A</span>}\mathrm{<span\; class="notranslate">\; twenty\; one</span>}& \mathrm{<span\; class="notranslate">\; A</span>}\mathrm{<span\; class="notranslate">\; twenty\; two</span>}\end{array}\right|}$

Using the determinant calculation method can avoid systematic errors. Moreover, the above algorithm is suitable for the following three situations

(1) There are any two or more of gaseous pollutants SO ₂ , NO ₂ , H ₂ , and O ₃ ;

(2) Any two or more of gas pollutants CO, H ₂ S, and H ₂ are present;

(3) Any two or more of gas pollutants HF, HCL, H ₂ S, and CL ₂ are present.

The mutual interference between H ₂ S, NO ₂ and SO ₂ and the mutual interference between H ₂ S and CO can be avoided by performing anti-gas cross-interference processing on the multi-channel detection signals.

In one embodiment of the present invention, the electromagnetic interference between multiple channels of anti-gas cross-interference detection signals can be reduced by means of mode suppression and electromagnetic shielding.

As shown in FIG. 4 , 410 is an internal detection space, and 420 is an electrical connection line. The gas boosted by the pressurization module 320 and heated by the temperature raising module 330 enters the internal detection space 410 , and the parameters of the gas are detected by the detection module 340 , and the detection module 340 further sends the detected parameters to the control module 350 .

As shown in Figure 5, the control module 350 includes a curve generation unit 351, an analysis unit 352 and an alarm unit 353, wherein the curve generation unit 351 is used to generate and display a gas statistical curve according to the gas conditions of the on-site air, wherein the gas statistical curve is used to indicate Indexes of various types of gases in the on-site air in different time periods, the analysis unit 352 is used to analyze the gas statistical curve to determine whether one or more indicators of the various types of gases in the on-site air exceed the The preset index; the alarm unit 353 is used to send an alarm signal when the index of one or more of the various types of gases in the on-site air exceeds the preset index corresponding to the gas.

The curve generation unit 351 analyzes and processes the parameters of multiple types of gases in the generated multi-channel detection signals, so as to obtain the gas conditions of the on-site gas. The curve generating unit 351 generates a gas statistical curve according to the acquired gas condition of the on-site gas, and displays the gas statistical curve to the monitoring personnel, so that the monitoring personnel can grasp the status of the on-site gas in time. Wherein, the gas statistical curve is used to indicate indicators of various gases in the on-site gas within different time periods.

The analysis unit 352 compares one or more gas indicators among the various types of gases in the on-site air with the preset indicators corresponding to the gas. When the index of one or more of the various types of gases in the on-site air exceeds the preset index corresponding to the gas, the alarm unit 353 will send an alarm signal, thereby prompting the monitoring personnel that the current on-site air quality is not Up to standard. After receiving the alarm signal, the monitoring personnel can make corresponding air purification treatment in time.

In one embodiment of the present invention, the control module 350 is also used to implement signal acquisition and analog-to-digital conversion, data processing, functional unit control, display, communication, keyboard or remote control interface, fault diagnosis and prompting, calibration, query and Data storage and other functions. The control module 350 is a management unit that realizes all functions of man-machine dialogue.

As shown in FIG. 6 , the air monitoring and analysis system provided by the embodiment of the present invention further includes a working state monitoring module 370 . The monitoring module 370 is used for each functional unit to have its normal working parameters when the environmental analyzer is working normally. When a functional unit is not within normal parameters, the analyzer is not working properly or is in a faulty state. The monitoring module 370 can normally detect the working status of the internal functional modules of the air monitoring and analysis system. When one of the monitored functional units is not normal, it will send out an out-of-operation point prompt or a fault warning. The monitoring module 370 can ensure the normal operation of the air monitoring and analysis system and the accuracy and reliability of the data.

In one embodiment of the present invention, the air monitoring and analysis system provided by the embodiment of the present invention further includes a front module 380, a display module 390, a keyboard or a remote controller 400, a power supply, a communication, an air pump, and the like. The air monitoring and analysis system provided by the embodiment of the present invention basically adopts common components or protocols of current products.

According to the air monitoring and analysis system of the embodiment of the present invention, the gas sample is collected through the gas sampling pump, and the gas is pressurized and heated through the pre-processing unit, thereby increasing the gas activity and unit density, and converting the gas concentration signal The electrical signal is transmitted to the acquisition and control unit of the single-board computer, and after signal processing, the result is displayed, stored, and transmitted. The air monitoring and analysis system of the embodiment of the present invention improves the signal sensitivity of the same gas sensor by 4-10 times in the detection, effectively improves the signal stability, improves the resolution, and makes the entire air monitoring and analysis system the lowest detection The threshold is reduced by an order of magnitude, fully meeting the technical requirements of air quality monitoring. Moreover, in the process of gas detection with cross interference, the factors affected by interfering gases are effectively eliminated.

The air monitoring and analysis system of the embodiment of the present invention achieves a resolution level that meets the requirements of ambient air quality detection through technological innovation based on the existing electrochemical technology, and can eliminate system errors caused by mutual interference of gases. The air monitoring and analysis system has the functions of continuous monitoring, portability, low power consumption, automatic data storage, expandable functions and monitoring pollutant types, communication, and matching with particle pollutant analysis instruments and meteorological monitoring devices. , with reliable technology for mass production.

In the description of this specification, descriptions referring to the terms "one embodiment", "some embodiments", "example", "specific examples", or "some examples" mean that specific features described in connection with the embodiment or example , structure, material or characteristic is included in at least one embodiment or example of the present invention. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

Although the embodiments of the present invention have been shown and described, those skilled in the art can understand that various changes, modifications and substitutions can be made to these embodiments without departing from the principle and spirit of the present invention. and modifications, the scope of the invention is defined by the appended claims and their equivalents.

Claims (16)

1. air monitering and analytical approach is characterized in that, comprise the steps:

Collection site gas, and the said gas on-site that will collect carries out pressurized treatments, wherein, the pressure that imposes on said gas on-site is equal to or less than the preset pressure threshold value;

Gas after the pressurized treatments is carried out hyperthermic treatment to preset temperature threshold value;

Gas after utilizing sensor groups to hyperthermic treatment detects obtaining the parameter of the polytype gas in the gas after the said hyperthermic treatment, and generates the multichannel detection signal corresponding to the parameter of said polytype gas;

Said multichannel detection signal is carried out analyzing and processing, obtain the gas-condition of said gas on-site.

2. air monitering as claimed in claim 1 and analytical approach is characterized in that, said preset pressure threshold value is less than or equal to the safe pressure threshold value of each sensor in the said sensor groups.

3. air monitering as claimed in claim 1 and analytical approach is characterized in that, said preset temperature threshold value is less than or equal to the safe temperature threshold value of each sensor in the said sensor groups.

4. air monitering as claimed in claim 1 and analytical approach is characterized in that, the parameter of the polytype gas that said sensor groups obtains comprises: the activity of the concentration of said polytype gas and said polytype gas.

5. air monitering as claimed in claim 1 and analytical approach; It is characterized in that; Before institute's multichannel detection signal is carried out analyzing and processing, comprise the steps: that also the gas after the said hyperthermic treatment is carried out anti-gas cross disturbs processing, generates the anti-gas cross Interference Detection of multichannel signal.

6. air monitering as claimed in claim 1 and analytical approach is characterized in that, also comprise the steps:

Reduce the electromagnetic interference (EMI) between the anti-gas cross Interference Detection of the said multichannel signal through common mode inhibition and electromagnetic screen method.

7. air monitering as claimed in claim 1 and analytical approach is characterized in that, also comprise the steps:

Gas-condition according to said on-the-spot air generates and demonstration gas statistic curve, and wherein, said gas statistic curve is used to indicate the index of the polytype gas of said gas on-site in different time sections.

8. air monitering as claimed in claim 7 and analytical approach is characterized in that, also comprise the steps:

Said gas statistic curve is analyzed, after one or more the index in the airborne polytype gas in said scene surpasses the preset index corresponding to this gas, sent alerting signal.

9. air monitering and analytic system is characterized in that, comprising:

Acquisition module is used for collection site gas;

Compression module is used for the said gas on-site that collects is carried out pressurized treatments, and wherein, the pressure that imposes on said gas on-site is equal to or less than the preset pressure threshold value;

The intensification module is used for the gas after the pressurized treatments is warming up to the preset temperature threshold value;

Detection module is used for the gas after the hyperthermic treatment is detected the parameter with the polytype gas of the gas after the acquisition hyperthermic treatment, and generates the multichannel detection signal corresponding to the parameter of said polytype gas;

Control module is used for said multichannel detection signal is carried out analyzing and processing, obtains the gaseous state of said gas on-site.

10. air monitering as claimed in claim 9 and analytic system; It is characterized in that said detection module is a sensor groups, wherein; Said sensor groups comprises at least one sensor; Wherein, each said sensor is used to detect a kind of parameter of types of gases, and generates road detection signal corresponding to the parameter of the type gas.

11. air monitering as claimed in claim 10 and analytic system is characterized in that, the parameter of said gas comprises: the concentration of the concentration of gas, the density of gas and pellet.

12. air monitering as claimed in claim 10 and analytic system is characterized in that, said preset pressure threshold value is less than or equal to the safe pressure threshold value of each sensor in the said sensor groups.

13. air monitering as claimed in claim 10 and analytic system is characterized in that, said preset temperature threshold value is less than or equal to the safe temperature threshold value of each sensor in the said sensor groups.

14. air monitering as claimed in claim 9 and analytic system is characterized in that, said intensification module is an insulation can.

15. air monitering as claimed in claim 9 and analytic system; It is characterized in that; Also comprise anti-gas cross interference processing module; Link to each other with said detection module with said intensification module respectively, be used for that the gas after the hyperthermic treatment of said intensification module is carried out anti-gas cross and disturb processing, generate the anti-gas cross Interference Detection of multichannel signal.

16. air detection as claimed in claim 9 and analytic system is characterized in that, said control module comprises:

The curve generation unit is used for generating and demonstration gas statistic curve according to the gas-condition of said on-the-spot air, and wherein, said gas statistic curve is used to indicate the index of the polytype gas of said on-the-spot air in different time sections;

Analytic unit is used for said gas statistic curve is analyzed, and whether surpasses the preset index corresponding to this gas to judge one or more the index in the airborne polytype gas in said scene;

Alarm unit is used for after one or more index of the airborne polytype gas in said scene surpasses the preset index corresponding to this gas, sending alerting signal.

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