An automatic analysis device for analyzing total gaseous mercury

Abstract

The present invention relates to an automatic analysis device for analyzing total gaseous mercury, which includes an automatic air intake mechanism provided with a first pipeline for transporting a sample gas to be measured; a condensation and cracking mechanism for receiving the sample gas to be measured, low-temperature enriching the total gaseous mercury in the sample gas to be measured, and completely pyrolyzing the total gaseous mercury in the sample gas to be measured into gaseous elemental mercury at high temperature; an automatic gas transmission mechanism provided with a second pipeline for transporting gaseous elemental mercury; a detection and analysis mechanism for analyzing the total concentration of gaseous elemental mercury; and a controller for controlling the automatic operation of the automatic air intake mechanism, the condensation and cracking mechanism, and the automatic gas transmission mechanism. The present invention can achieve complete collection of the total gaseous mercury in the sample gas to be measured, improve the accuracy of the analysis of the total mercury concentration in the sample gas to be measured, thereby truly realizing the measurement of the total mercury content of all gases in the sample, and at the same time realizing a simple and reliable on-line analysis technology and reducing the analysis cost.

Description

Technical Field

[0001] The present invention relates to the field of sewage monitoring, and particularly to an automatic analysis device for analyzing total mercury in water quality. Background Art

[0002] Mercury is a toxic and harmful heavy metal element that exists in liquid state under normal temperature and pressure, and it is volatile. Therefore, this element is ubiquitous in nature, which can bring great ecological risks to the ecological environment and cause human poisoning. Therefore, after multiple rounds of negotiations organized by the United Nations, the Minamata Convention on Mercury, a global mercury convention with legal effect, was promulgated and came into force globally on August 16, 2017, aiming to reduce emissions and control mercury pollution. According to the requirements of the convention, it is necessary to monitor environmental mercury in order to evaluate the effectiveness of implementing the convention. Therefore, the monitoring of environmental mercury, especially the long-term monitoring of atmospheric mercury, is extremely important for evaluating the control measures and emission reduction effectiveness of mercury pollution in China. In terms of atmospheric mercury, it is mainly divided into gaseous elemental mercury (GEM), reactive gaseous mercury (GOM) and particulate mercury (PBM) according to physical and chemical forms. Generally, the sum of the three forms of mercury becomes the total gaseous mercury (TGM) in the atmosphere. Atmospheric mercury mainly comes from mercury emissions from human activities (anthropogenic sources) and natural processes (natural sources). Among them, anthropogenic sources mainly include fossil fuel combustion, incineration of municipal waste and medical waste, non-ferrous metal smelting, cement production, gold smelting activities and chlor-alkali industry, etc., while natural sources mainly include volcanic geothermal activities, volatilization on the surface of soil and water bodies, plant transpiration and forest fires, etc. The monitoring of atmospheric mercury can understand the distribution characteristics and transmission laws of atmospheric mercury, analyze the sources of atmospheric mercury pollution, optimize the emission inventory of atmospheric mercury, evaluate the long-term change trend of atmospheric mercury, and provide data support for evaluating the effectiveness of implementing the mercury convention, etc. At present, the global measurement of gaseous mercury is mainly to first remove air particulates by using a Teflon filter membrane (pore size greater than 2 microns), then enrich by gold amalgamation, and then heat and desorb, and introduce it into an atomic fluorescence or atomic absorption mercury detector through a carrier gas for analysis. This method can only measure elemental mercury, a part of reactive mercury and particulate mercury in the air, and cannot completely measure the true total gaseous mercury.

[0003] In order to prevent the influence of large particulates in the gas sample on the mercury enrichment tube and the detector in traditional total gaseous mercury analysis, it is necessary to remove the large particulates in the gas sample before mercury enrichment, and only allow particulates smaller than PM2.5 to enter. This also removes most of the particulate mercury in the gas sample, resulting in that the analyzed total gaseous mercury does not contain most of the particulate mercury. In addition, the particulates adsorbed on the filter membrane will also absorb elemental mercury and reactive mercury in the gas sample. Therefore, the above reasons can lead to the measured total gaseous mercury concentration being lower than the true total mercury concentration. Summary of the Invention

[0004] (1) Technical Problems to be Solved

[0005] An embodiment of the present invention provides an automatic analysis device for analyzing gaseous total mercury. The controller controls the automatic intake mechanism to automatically input the sample gas to be measured, and controls the condensation and cracking mechanism to automatically achieve low-temperature enrichment and high-temperature analysis of the gaseous total mercury in the sample gas to be measured, so as to obtain all gaseous elemental mercury. Then, it controls the automatic gas transmission mechanism to automatically output the gaseous elemental mercury into the detection and analysis mechanism, and uses the detection and analysis mechanism to measure the gaseous elemental mercury to obtain the total mercury concentration of the sample gas to be measured. It can completely collect the gaseous total mercury in the sample gas to be measured, improve the accuracy of the total mercury concentration analysis of the sample gas to be measured, thereby truly realizing the measurement of the total mercury content of all gases in the sample, and at the same time realizing a simple and reliable on-line analysis technology and reducing the analysis cost.

[0006] (2) Technical solution

[0007] In a first aspect, an embodiment of the present invention provides an automatic analysis device for analyzing gaseous total mercury, including an automatic intake mechanism provided with a first pipeline for transporting the sample gas to be measured; a condensation and cracking mechanism for receiving the sample gas to be measured and low-temperature enriching the gaseous total mercury in the sample gas to be measured, and for completely high-temperature analyzing the gaseous total mercury into gaseous elemental mercury; an automatic gas transmission mechanism provided with a second pipeline for transporting the gaseous elemental mercury; a detection and analysis mechanism for analyzing the total concentration of the gaseous elemental mercury; and a controller for controlling the automatic operation of the automatic intake mechanism, the condensation and cracking mechanism, and the automatic gas transmission mechanism.

[0008] Further, the condensation and cracking mechanism includes a container communicated with the first pipeline and the second pipeline for enriching the gaseous total mercury in the sample gas to be measured, a condensation unit for low-temperature condensing the gaseous total mercury in the container, and a cracking unit for high-temperature analyzing the gaseous total mercury in the container into the gaseous elemental mercury.

[0009] Further, the condensation unit includes a condensation tank for accommodating the container, a coolant storage tank communicated with the condensation tank through an injection pipeline and a return pipeline, a liquid pump provided on the injection pipeline, a stop valve provided on the return pipeline, a liquid level sensor for detecting the liquid level height, a thermometer for detecting the temperature in the condensation tank, and a temperature controller for maintaining the temperature in the condensation tank at a set temperature in the condensation tank.

[0010] Further, the cracking unit includes a first heating wire wound around the outer wall of the container.

[0011] Further, the interior of the container is filled with an enrichment agent for enriching the total gaseous mercury in the gas of the sample to be measured. The output end of the first pipeline and the input end of the second pipeline are both arranged inside the container. The output end of the first pipeline is buried in the enrichment agent, and the input end of the second pipeline is located above the enrichment agent.

[0012] Further, the automatic air intake mechanism further includes a first electromagnetic valve and a second electromagnetic valve which are arranged on the first pipeline and are communicated with each other. The first electromagnetic valve is provided with a first pipe interface for inputting the gas of the sample to be measured and a second pipe interface for communicating with the second electromagnetic valve. The second electromagnetic valve is further provided with a third pipe interface for inputting carrier gas, a fourth pipe interface for communicating with the first electromagnetic valve, and a fifth pipe interface for communicating with the container.

[0013] Further, the first electromagnetic valve is further provided with a sixth pipe interface for conveying mercury standard gas and a seventh pipe interface for conveying mercury-free air.

[0014] Further, the automatic air intake mechanism further includes an air extraction pump for extracting the gas of the sample to be measured from the first pipeline into the second pipeline. The automatic gas transmission mechanism includes a mass flow controller for controlling the flow rate of the carrier gas, a third electromagnetic valve, a drying tube for drying the gaseous elemental mercury, a fourth electromagnetic valve, an enrichment component for secondary purification of the gaseous elemental mercury, and a fifth electromagnetic valve which are arranged on the second pipeline and are communicated with each other. The third electromagnetic valve is arranged between the mass flow controller and the drying tube. The fourth electromagnetic valve is arranged between the drying tube and the enrichment component. The fifth electromagnetic valve is arranged between the enrichment component and the detection and analysis mechanism. The third electromagnetic valve is provided with an eighth pipe interface for communicating with the air extraction pump.

[0015] Further, the fourth electromagnetic valve is provided with a ninth pipe interface for inputting carrier gas. The fifth electromagnetic valve is provided with a tenth pipe interface for discharging waste gas and an eleventh pipe interface for communicating with the detection and analysis mechanism.

[0016] Further, the enrichment component includes a mercury enrichment tube and a second heating wire wound around the outside of the mercury enrichment tube. The third electromagnetic valve is further provided with a twelfth pipe interface for communicating with the mass flow controller and a thirteenth pipe interface for communicating with the drying tube. The fourth electromagnetic valve is further provided with a fourteenth pipe interface for communicating with the other end of the drying tube and a fifteenth pipe interface for communicating with the mercury enrichment tube. The fifth electromagnetic valve is further provided with a sixteenth pipe interface for communicating with the other end of the mercury enrichment tube.

[0017] (3) Beneficial effects

[0018] In summary, the controller of the present invention controls the automatic intake mechanism to automatically input the gas of the sample to be tested, controls the condensation and cracking mechanism to automatically and stepwise achieve low-temperature enrichment and high-temperature analysis of the total gaseous mercury in the gas of the sample to be tested, and then obtains all the gaseous elemental mercury. It controls the automatic gas transmission mechanism to automatically output the gaseous elemental mercury into the detection and analysis mechanism, and uses the detection and analysis mechanism to measure the gaseous elemental mercury to obtain the total mercury concentration of the gas of the sample to be tested. It can completely collect various forms of mercury (including gaseous elemental mercury, active gaseous mercury, and particulate mercury) in the gas of the sample to be tested, improve the accuracy of the analysis of the total mercury concentration of the gas of the sample to be tested, thereby truly realizing the measurement of the total mercury content of the gas in the sample, and at the same time realizing a simple and reliable on-line analysis technology, which is more suitable for long-term on-line monitoring, and is easy to maintain. The entire detection and analysis process does not require the existing technology to regularly replace the filter membrane to filter the sample gas, nor does it require chemical reagents to enrich the sample, thereby reducing the detection and analysis cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required to be used in the embodiments of the present invention will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0020] Figure 1 It is a schematic structural diagram of the present invention.

[0021] In the figure:

[0022] 1 - First pipeline; 11 - First solenoid valve; 12 - Second solenoid valve; 111 - First pipe interface; 112 - Sixth pipe interface; 113 - Seventh pipe interface; 114 - Second pipe interface; 121 - Third pipe interface; 122 - Fourth pipe interface; 123 - Fifth pipe interface

[0023] 2 - Second pipeline; 21 - Mass flow controller; 22 - Third solenoid valve; 23 - Fourth solenoid valve; 25 - Drying tube; 26 - Enrichment component; 27 - Air extraction pump; 221 - Twelfth pipe interface; 222 - Thirteenth pipe interface; 223 - Eighth pipe interface; 231 - Ninth pipe interface; 232 - Fourteenth pipe interface; 233 - Fifteenth pipe interface; 241 - Tenth pipe interface; 242 - Sixteenth pipe interface; 243 - Eleventh pipe interface; 261 - Mercury enrichment tube; 262 - Second heating wire

[0024] 3 - Container; 31 - Enriching agent

[0025] 41-condensate tank; 42-injection pipeline; 43-return pipeline; 44-condensing agent storage tank; 45-liquid pump; 46-stop valve; 47-thermometer; 48-thermostat; 49-first heating wire;

[0026] 5- Mercury analyzer. DETAILED DESCRIPTION

[0027] The following is a further detailed description of the embodiments of the present invention in conjunction with the accompanying drawings and examples. The detailed description of the following embodiments and the accompanying drawings are used to exemplarily illustrate the principles of the present invention, but cannot be used to limit the scope of the present invention, that is, the present invention is not limited to the described embodiments, and covers any modification, replacement and improvement of parts, components and connection modes without departing from the spirit of the present invention.

[0028] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0029] Figure 1 is a schematic diagram of the structure of an automatic analysis device for analyzing total mercury in gaseous state according to an embodiment of the present invention. Figure 1 As shown, the automatic analysis device includes an automatic air intake mechanism, which is provided with a first pipeline 1 for conveying the sample gas to be tested; a condensation and cracking mechanism, which is used to receive the sample gas to be tested and to enrich the gaseous total mercury in the sample gas to be tested at low temperature, and to resolve all the gaseous total mercury into gaseous elemental mercury at high temperature; an automatic gas delivery mechanism, which is provided with a second pipeline 2 for conveying gaseous elemental mercury; a detection and analysis mechanism, which is used to analyze the total concentration of gaseous elemental mercury; and a controller, which is used to control the automatic operation of the automatic air intake mechanism, the condensation and cracking mechanism, and the automatic gas delivery mechanism.

[0030] The present invention controls an automatic air intake mechanism to automatically input a sample gas to be tested through a controller, controls a condensation and cracking mechanism to automatically and step-by-step realize low-temperature enrichment and high-temperature analysis of the total gaseous mercury in the sample gas to be tested, obtains all the gaseous elemental mercury, controls an automatic gas transmission mechanism to automatically output the gaseous elemental mercury to a detection and analysis mechanism, uses the detection and analysis mechanism to measure the gaseous elemental mercury, and obtains the total mercury concentration of the sample gas to be tested. The present invention can realize complete collection of various forms of mercury in the total gaseous mercury (including gaseous elemental mercury, active gaseous mercury and particulate mercury) in the sample gas to be tested, improves the accuracy of the total mercury concentration analysis of the sample gas to be tested, thereby truly realizing the measurement of all the total mercury content of the gas in the sample, and at the same time realizing a simple and reliable online analysis technology and reducing the analysis cost.

[0031] As a preferred embodiment, Figure 1As shown in the figure, the condensation and cracking mechanism includes a container 3 that is connected to the first pipeline 1 and the second pipeline 2 and is used to enrich the total gaseous mercury in the gas of the sample to be measured, a condensation unit for low-temperature condensing the total gaseous mercury in the container 3, and a cracking unit for thermally decomposing the total gaseous mercury in the container 3 into gaseous elemental mercury. The inside of the container 3 is filled with an enrichment agent 31 for enriching the total gaseous mercury in the gas of the sample to be measured. The enrichment agent can be quartz sand, silicon carbide particles, or a combination of both. The output end of the first pipeline 1 is buried in the enrichment agent 31, and the input end of the second pipeline 2 is located above the enrichment agent 31. By using the characteristic of the melting point of mercury itself, various forms of gaseous mercury (including gaseous elemental mercury, reactive gaseous mercury, and particulate mercury) in the gas of the sample to be measured input into the container 3 can be enriched by performing low-temperature treatment on the container 3. There is no need to use a Teflon filter membrane to filter the total gaseous mercury in the sample to be measured, thus removing particulate mercury in the large particle state and affecting the accuracy of the total mercury concentration analysis. By heating and raising the temperature of the container 3, the total gaseous mercury enriched on the enrichment agent 31 can be volatilized again to form gaseous elemental mercury, and then carrier gas (high-purity nitrogen) is injected into the third pipe interface 121 of the second solenoid valve 12 (described in detail later) to transport the gaseous elemental mercury from the container 3 into the detection and analysis mechanism, realizing the purification of the total gaseous mercury in the gas of the sample to be measured.

[0032] As another preferred embodiment, as Figure 1As shown in the figure, the condensation unit includes a condensation tank 41 for accommodating the container 3, and a coolant storage tank 44 that is connected to the condensation tank 41 through both an injection pipeline 42 and a reflux pipeline 43. The coolant storage tank 44 is filled with a coolant (methanol or ethylene glycol hydrate or a mixture of both). A liquid pump 45 is provided on the injection pipeline 42, and a stop valve 46 is provided on the reflux pipeline 43. A liquid level sensor for detecting the liquid level height (not shown in the figure), a thermometer 47 for detecting the temperature inside the condensation tank 41, and a temperature controller 48 for maintaining the inside of the condensation tank 41 at a set temperature (preferably -50°C, lower than the melting point of mercury) are also provided inside the condensation tank 41. The cracking unit includes a first heating wire 49 wound around the outer wall of the container 3. The output end of the first pipeline 1 and the input end of the second pipeline 2 are both provided inside the container 3. Through the mutual cooperation of the liquid pump 45 and the stop valve 46, when the container 3 needs to be cryogenically treated, the coolant in the coolant storage tank 44 is pumped from the coolant storage tank 44 through the injection pipeline 42 into the condensation tank 41. When performing high-temperature desorption treatment, the stop valve 46 is opened to return the coolant in the condensation tank 41 back to the coolant storage tank 44 through the reflux pipeline 43, enabling automatic transportation and reflux of the coolant; the liquid level sensor is used to detect the rising liquid level of the condensate in the condensation tank 41. When the liquid level height of the coolant is slightly higher than the height of the enrichment agent 31 in the container 3, the liquid pump 45 is controlled to stop injecting the coolant into the condensation tank 41 to prevent excessive injection of the coolant and overflow, while also increasing the cost of cryogenic treatment of the coolant; the temperature controller 48 is used to cool the temperature of the coolant in the condensation tank 41 to a preset temperature value (minus 50°C), which can effectively ensure full cryogenic condensation of gaseous mercury in various forms in the sample gas to be measured in the container 3 and improve the comprehensive collection of mercury elements; through the real-time monitoring of the thermometer 47, it is ensured that the temperature controller 48 can dynamically balance and maintain the temperature of the coolant in the condensation tank 41 at the preset temperature value, guaranteeing the condensation effect of gaseous mercury in various forms in the sample gas to be measured in the container 3.

[0033] As another preferred embodiment, as Figure 1As shown in the figure, the automatic air intake mechanism further includes a first solenoid valve 11 and a second solenoid valve 12 provided on the first pipeline 1 and communicating with each other. The first solenoid valve 11 is provided with a first pipe interface 111 for inputting the gas of the sample to be measured and a second pipe interface 114 for communicating with the second solenoid valve 12. The second solenoid valve 12 is further provided with a third pipe interface 121 for inputting carrier gas, a fourth pipe interface 122 communicating with the first solenoid valve 11, and a fifth pipe interface 123 communicating with the container 3. By controlling the opening of the first pipe interface 111, the second pipe interface 114, the fourth pipe interface 122, and the fifth pipe interface 123 and the closing of the third pipe interface 121, the automatic transportation of the gas of the sample to be measured into the container 3 can be realized. And by controlling the closing of the first pipe interface 111 and the fourth pipe interface 122 and the opening of the third pipe interface 121 and the fifth pipe interface 123, the injection of carrier gas (high-purity nitrogen) into the container 3 can be realized to discharge the gaseous elemental mercury after high-temperature desorption or high-temperature pyrolysis from the container 3 into the second pipeline 2. It should be noted here that controlling the opening and closing of the first pipe interface, the second pipe interface, the third pipe interface, the fourth pipe interface, and the fifth pipe interface actually controls the opening and closing of the corresponding valves (not shown in the figure) provided in the corresponding solenoid valves. The opening and closing of each pipe interface described in this application refer to the opening and closing of the corresponding valves on the corresponding solenoid valves, which will not be elaborated later.

[0034] As another alternative embodiment.

[0035] Preferably, as Figure 1 shown, the first solenoid valve 11 is further provided with a sixth pipe interface 112 for transporting mercury standard gas and a seventh pipe interface 113 for transporting mercury-free air. By providing the sixth pipe interface 112 for transporting mercury standard gas and the seventh pipe interface 113 for transporting mercury-free air on the first solenoid valve 11, mercury-free air can be introduced into the first pipeline 1, the container 3, and the second pipeline 2 before measuring and analyzing the total mercury concentration of the gas of the sample to be measured until the total mercury concentration value measured by the detection and analysis mechanism is zero, so as to prevent the residual gaseous mercury in the entire analysis device from affecting the accuracy of the formal measurement or the next measurement of the total mercury concentration. On the other hand, mercury standard gas can be introduced into the first pipeline 1, the container 3, and the second pipeline 2 before measuring and analyzing the total mercury concentration of the gas of the sample to be measured to calibrate and calibrate the total mercury concentration of the entire analysis device, so as to accurately detect the recovery rate of the gas of the sample to be measured (that is, when the difference degree between the total mercury concentration value of the gas of the sample to be measured and the total mercury concentration value of the mercury standard gas is detected, it can be used as a reference basis for whether the gas of the sample to be measured is recovered).

[0036] Preferably, as Figure 1As shown in the figure, the automatic gas injection mechanism is provided on the second pipeline 2 and includes a mass flow controller 21, a third solenoid valve 22, a drying tube 25 for drying gaseous elemental mercury, a fourth solenoid valve 23, an enrichment assembly 26 for secondary purification of gaseous elemental mercury, and a fifth solenoid valve 24, which are interconnected and used to control the carrier gas flow. The third solenoid valve 22 is arranged between the mass flow controller 21 and the drying tube 25, the fourth solenoid valve 23 is arranged between the drying tube 25 and the enrichment assembly 26, and the fifth solenoid valve 24 is arranged between the enrichment assembly 26 and the detection and analysis mechanism. The automatic gas intake mechanism further includes a suction pump 27 for extracting the gas of the sample to be measured from the first pipeline 1 into the second pipeline 2. An eighth pipe interface 223 for communicating with the suction pump 27 is provided on the third solenoid valve 22. The mass flow controller 21 is used to monitor the flow rate of the gas of the sample to be measured extracted by the suction pump 27 in real time, so as to automatically adjust the intake flow rate of the gas of the sample to be measured, prevent waste caused by the inability to quickly condense due to excessive intake flow rate of the gas of the sample to be measured or affect the efficiency of automatic analysis due to too small intake flow rate and long intake time, and at the same time record the total flow rate of the gas of the sample to be measured passing through the mass flow controller; by setting a desiccant, such as soda lime, etc., in the drying tube to adsorb water vapor and other impurity gases mixed in the gaseous elemental mercury, it is possible to avoid inaccurate influence on the measurement results of the detection and analysis mechanism caused by water vapor and other impurity gases; by setting a mercury enrichment tube between the fourth solenoid valve and the fifth solenoid valve to perform secondary purification on the gaseous elemental mercury after removing water vapor and other impurity gases, it is ensured that the purity of the gaseous elemental mercury entering the detection and analysis mechanism is higher, making the measurement results more accurate.

[0037] Preferably, as Figure 1 shown in the figure, a ninth pipe interface 231 for inputting carrier gas is provided on the fourth solenoid valve 23, a tenth pipe interface 241 for discharging waste gas (water vapor and other impurity gases except high-purity nitrogen) and an eleventh pipe interface 243 for communicating with the detection and analysis mechanism are provided on the fifth solenoid valve 24. The enrichment assembly 26 includes a mercury enrichment tube 261 and a second heating wire 262 wound around the outside of the mercury enrichment tube 261. A twelfth pipe interface 221 for communicating with the mass flow controller 21 and a thirteenth pipe interface 222 for communicating with the drying tube 25 are further provided on the third solenoid valve 22. A fourteenth pipe interface 232 for communicating with the other end of the drying tube 25 and a fifteenth pipe interface 233 for communicating with the mercury enrichment tube 261 are further provided on the fourth solenoid valve 23. A sixteenth pipe interface 242 for communicating with the other end of the mercury enrichment tube 261 is further provided on the fifth solenoid valve 24. By controlling the closure of the fourteenth pipe interface 232 and the eleventh pipe interface 243 and opening the ninth pipe interface 231, the fifteenth pipe interface 233, the sixteenth pipe interface 242 and the tenth pipe interface 241, it is possible to perform secondary enrichment on the gaseous elemental mercury after removing water vapor and other impurity gases, thereby improving the purity of the gaseous elemental mercury to be measured and ensuring the accuracy of the measurement results.

[0038] Preferably, as Figure 1 shown, the detection and analysis institution is a mercury analyzer 5, and the mercury analyzer 5 can be an atomic fluorescence or atomic absorption mercury detector.

[0039] To further understand the creativity of the present invention, the working principle of the present invention is described as follows, as Figure 1As shown in the figure, the automatic analysis process implemented by the automatic analysis device for analyzing total gaseous mercury of the present invention includes a first control stage (the stage of injecting a coolant into the condensation tank and maintaining a preset temperature), that is, the controller controls the liquid pump 45 to start, and at the same time closes the stop valve 46. The liquid pump 45 pumps the coolant in the coolant storage tank 44 into the condensation tank 41 until the liquid level sensor detects that the liquid level of the coolant in the condensation tank 41 reaches the preset position (that is, slightly higher than the height formed by the enrichment agent 31 in the container 3 in the container 3). Then, the liquid pump 45 is closed and the temperature controller 48 is turned on to cool the coolant in the condensation tank 41 and maintain it at the preset temperature (that is, -50°C); the second control stage (the stage of automatic air intake and condensation enrichment), that is, opening the first pipe interface 111, the second pipe interface 114, the fourth pipe interface 122, the fifth pipe interface 123, the twelfth pipe interface 221 and the eighth pipe interface 223, and closing the sixth pipe interface 112, the seventh pipe interface 113, the third pipe interface 121 and the thirteenth pipe interface 222, and at the same time starting the air extraction pump 27 and the mass flow controller 21. Various forms of mercury (including gaseous elemental mercury, reactive gaseous mercury and particulate mercury) in the sample gas to be measured are enriched by the low-temperature condensed enrichment agent 31 when flowing through the container 3, and the mass flow controller 21 records the flow rate of the sample gas to be measured. When the preset sampling time or sampling volume is reached, it is used as a control signal for the completion of enrichment).In the third control stage (high temperature analysis and gas transmission detection stage), the vacuum pump 27 and the fourth interface 122 are controlled to be closed, and the stop valve 46 is opened to allow the condensing agent in the condensation tank 41 to automatically flow into the condensing agent storage tank 44 through the reflux pipeline 43. The thermostat 48 is then adjusted to heat the first heating wire 49 to a preset high temperature (i.e., 900° C.), and all forms of mercury enriched in the enrichment agent 31 are completely analyzed into gaseous elemental mercury. The sixth pipe interface 112, the eighth pipe interface 223, the ninth pipe interface 231, and the eleventh pipe interface 243 are controlled to be closed. At the same time, the third pipe interface 121, the thirteenth pipe interface 222, the fourteenth pipe interface 232, the fifteenth pipe interface 233, the sixteenth pipe interface 242 and the tenth pipe interface 241 are opened, and the carrier gas (high-purity nitrogen or argon) introduced from the third pipe interface 121 brings the analyzed gaseous elemental mercury out of the container 3 and passes through the twelfth pipe interface 221, the thirteenth pipe interface 222, the drying tube 25 (for removing water vapor and other impurity gases mixed in the gaseous elemental mercury), the fourteenth pipe interface 232 and the fifteenth pipe interface 233 in sequence. The mercury enters the mercury enrichment tube 261 (made of pure gold, quartz gold-plated, silicon carbide or activated carbon) to perform secondary purification and enrichment of gaseous elemental mercury. The waste gas (high-purity nitrogen and other impurity gases) formed at the same time is discharged to the external atmosphere through the sixteenth pipe interface 242 and the tenth pipe interface 241 in sequence. After the enrichment process is completed (the enrichment time is controlled to be 30-60 minutes, for example, by a timer), the fourteenth pipe interface 232 and the tenth pipe interface 241 are controlled to be closed, and the ninth pipe interface 231 and the eleventh pipe interface 242 are opened at the same time. 43, and start the second heating wire 262 to heat up to 500°C-600°C to re-analyze the mercury element enriched in the mercury enrichment tube into gaseous elemental mercury, inject carrier gas (high-purity nitrogen or argon) into the ninth pipe interface 231 to allow the gaseous elemental mercury that has been secondary analyzed to enter the mercury detector or mercury analyzer 5 through the sixteenth pipe interface 242 and the eleventh pipe interface 243 in sequence, and calculate the total mercury concentration in the sample gas to be tested based on the measured mercury content and the total flow rate or total sampling volume of the sample gas to be tested recorded by the mass flow controller 21. ;

[0040] To inject mercury standard gas and mercury-free air, it is only necessary to switch the first pipe interface 111 to the corresponding sixth pipe interface 112 or seventh pipe interface 113 in the second control stage. The remaining steps are the same as the analysis and measurement process of the sample gas to be tested, and will not be repeated here.

[0041] It should be clear that the various embodiments in this specification are described in a progressive manner, and the same or similar parts between the various embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. The present invention is not limited to the specific steps and structures described above and shown in the figures. In addition, for the sake of brevity, a detailed description of known methods and technologies is omitted here.

[0042] The above are only the embodiments of the present application and do not limit the present application. For those skilled in the art, various modifications and variations can be made to the present application without departing from the scope of the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included within the scope of the claims of the present application.

Claims

1. An automatic analysis device for analyzing total gaseous mercury, characterized in that, Comprising: An automatic air intake mechanism, provided with a first pipeline (1) for conveying the gas of the sample to be tested; A condensation and cracking mechanism, configured to receive the gas of the sample to be tested and low-temperature enrich the total gaseous mercury in the gas of the sample to be tested, the total gaseous mercury including gaseous elemental mercury, active gaseous mercury and particulate mercury, and configured to thermally desorb all of the total gaseous mercury into gaseous elemental mercury; an automatic gas transmission mechanism, provided with a second pipeline (2) for conveying the gaseous elemental mercury; A detection and analysis mechanism, configured to analyze the total concentration of the gaseous elemental mercury; A controller, configured to control the automatic operation of the automatic air intake mechanism, the condensation and cracking mechanism and the automatic gas transmission mechanism; The condensation and cracking mechanism includes a container (3) communicated with the first pipeline (1) and the second pipeline (2) for enriching the total gaseous mercury in the gas of the sample to be tested, a condensation unit for low-temperature condensing the total gaseous mercury in the container (3), and a cracking unit for thermally desorbing the total gaseous mercury in the container (3) into the gaseous elemental mercury; The interior of the container (3) is filled with an enrichment agent (31) for enriching the total gaseous mercury in the gas of the sample to be tested, the enrichment agent (31) being quartz sand or silicon carbide particles or a combination of both. The output end of the first pipeline (1) and the input end of the second pipeline (2) are both disposed inside the container (3), and the output end of the first pipeline (1) is buried in the enrichment agent (31), and the input end of the second pipeline (2) is located above the enrichment agent (31); The automatic analysis device controls, through the controller, the automatic input of the gas of the sample to be tested by the automatic air intake mechanism, controls the condensation and cracking mechanism to automatically and stepwise achieve low-temperature enrichment and high-temperature desorption of the total gaseous mercury in the gas of the sample to be tested to obtain all gaseous elemental mercury, then controls the automatic gas transmission mechanism to automatically output the gaseous elemental mercury into the detection and analysis mechanism, and uses the detection and analysis mechanism to measure the gaseous elemental mercury to obtain the total mercury concentration of the gas of the sample to be tested.

2. The automatic analysis device for analyzing total gaseous mercury according to claim 1, characterized in that, The condensation unit includes a condensation tank (41) for accommodating the container (3), and a coolant storage tank (44) communicated with the condensation tank (41) through an injection pipeline (42) and a return pipeline (43). A liquid pump (45) is provided on the injection pipeline (42), a stop valve (46) is provided on the return pipeline (43), a liquid level sensor for detecting the liquid level height, a thermometer (47) for detecting the temperature inside the condensation tank (41), and a temperature controller (48) for maintaining the temperature inside the condensation tank (41) at a set temperature are further provided inside the condensation tank (41).

3. The automatic analysis device for analyzing total gaseous mercury according to claim 1, characterized in that, The cracking unit includes a first heating wire (49) wound around the outer wall of the container (3).

4. The automatic analysis device for analyzing total gaseous mercury according to claim 1, characterized in that, The automatic air intake mechanism further includes a first solenoid valve (11) and a second solenoid valve (12) which are arranged on the first pipeline (1) and communicate with each other. A first pipe interface (111) for inputting the gas of the sample to be measured and a second pipe interface (114) for communicating with the second solenoid valve (12) are arranged on the first solenoid valve (11). The second solenoid valve (12) further has a third pipe interface (121) for inputting carrier gas, a fourth pipe interface (122) communicating with the first solenoid valve (11), and a fifth pipe interface (123) communicating with the container (3).

5. The automatic analysis device for analyzing total gaseous mercury according to claim 4, characterized in that, A sixth pipe interface (112) for transporting mercury standard gas and a seventh pipe interface (113) for transporting mercury-free air are further arranged on the first solenoid valve (11).

6. The automatic analysis device for analyzing total gaseous mercury according to claim 4, characterized in that, The automatic air intake mechanism further includes an air extraction pump (27) for extracting the gas of the sample to be measured from the first pipeline (1) into the second pipeline (2). The automatic gas transmission mechanism includes a mass flow controller (21) for controlling the flow rate of carrier gas, a third solenoid valve (22), a drying tube (25) for drying the gaseous elemental mercury, a fourth solenoid valve (23), an enrichment component (26) for secondary purification of the gaseous elemental mercury, and a fifth solenoid valve (24) which are arranged on the second pipeline (2) and communicate with each other. The third solenoid valve (22) is arranged between the mass flow controller (21) and the drying tube (25). The fourth solenoid valve (23) is arranged between the drying tube (25) and the enrichment component (26). The fifth solenoid valve (24) is arranged between the enrichment component (26) and the detection and analysis mechanism. An eighth pipe interface (223) for communicating with the air extraction pump (27) is arranged on the third solenoid valve (22).

7. The automatic analysis device for analyzing total gaseous mercury according to claim 6, characterized in that, A ninth pipe interface (231) for inputting carrier gas is arranged on the fourth solenoid valve (23). A tenth pipe interface (241) for discharging waste gas and an eleventh pipe interface (243) communicating with the detection and analysis mechanism are arranged on the fifth solenoid valve (24).

8. The automatic analysis device for analyzing total gaseous mercury according to claim 7, characterized in that, The enrichment component (26) includes a mercury enrichment tube (261) and a second heating wire (262) wound around the outside of the mercury enrichment tube (261). A twelfth pipe interface (221) for communicating with the mass flow controller (21) and a thirteenth pipe interface (222) communicating with the drying tube (25) are further arranged on the third solenoid valve (22). A fourteenth pipe interface (232) for communicating with the other end of the drying tube (25) and a fifteenth pipe interface (233) for communicating with the mercury enrichment tube (261) are further arranged on the fourth solenoid valve (23). A sixteenth pipe interface (242) for communicating with the other end of the mercury enrichment tube (261) is further arranged on the fifth solenoid valve (24).

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