Online continuous monitoring system for high-concentration carbon dioxide

Abstract

The utility model relates to an online continuous monitoring system for high-concentration carbon dioxide. Comprising a sampling probe, a sucking pump and a CO2 analyzer, the sampling probe is connected with an inlet of the sucking pump through a sampling pipeline, a sampling valve, a filter and a condenser are installed on the pipeline, and an outlet of the sucking pump is connected with an emptying pipeline and a measuring pipeline at the same time; the measuring pipeline is connected to a gas inlet of the CO2 analyzer, a filter and a condenser are mounted on the measuring pipeline, and a gas outlet of the CO2 analyzer is connected to another emptying pipeline; the device further comprises a half-course calibration pipeline and a whole-course calibration pipeline, one end of the half-course calibration pipeline is connected to a reversing solenoid valve arranged on the measuring pipeline, and one end of the whole-course calibration pipeline is connected to the sampling pipeline; the device further comprises a back flushing pipeline. The system has a calibration function and a function of cleaning the sampling probe in a back flushing manner, and the accuracy of monitoring the CO2 concentration is improved by calibrating the system and keeping the sampling probe clean.

Description

Technical Field

[0001] The utility model belongs to the technical field of online monitoring equipment, and in particular relates to an online continuous monitoring system for high-concentration carbon dioxide. Background Art

[0002] Carbon dioxide emissions are a key component of national carbon monitoring and the cornerstone of achieving national carbon peak and carbon neutrality. Carbon dioxide emission reduction relies on an accurate carbon emissions monitoring system. Currently, the monitoring methods and technical foundations for carbon dioxide are relatively weak, especially when the concentration of carbon dioxide emitted by enterprises is high. High-concentration carbon dioxide monitoring technology needs to be further improved. High-precision CO2 analyzers are currently available, but monitoring systems based on these analyzers also require appropriate sampling methods and calibration of the analyzer and the entire system to ensure accurate measurement of carbon dioxide concentrations.

[0003] The specification of Chinese invention patent CN116819011 A discloses a carbon dioxide monitoring system and method for key links in coal-fired power plants. The technical solution disclosed in this patent only considers the sampling and measurement of the system. In actual application of the equipment, because flue gas usually contains water vapor, particulate matter or crystals, it is easy to cause blockage of the probe pipeline, resulting in a reduction in the amount of sampled gas, which seriously affects the accuracy of the measurement data. Ensuring the quality of the sample gas is particularly important in the scenario of high-concentration carbon dioxide concentration monitoring. On the other hand, as the application time goes by, the monitoring equipment also needs regular maintenance and calibration to ensure the accuracy of the measurement data.

[0004] The existing CO2 monitoring system is difficult to meet the above requirements and it is difficult to continuously obtain accurate monitoring data on CO2 concentration. Further development and design of the monitoring system is needed. Utility Model Content

[0005] The purpose of this utility model is to provide an online continuous monitoring system for high-concentration carbon dioxide, which has a calibration function and a backflushing cleaning function for the sampling probe. The accuracy of CO2 concentration monitoring is improved by calibrating the system and keeping the sampling probe clean.

[0006] The technical solution adopted by the utility model is: a high-concentration carbon dioxide online continuous monitoring system, including a sampling probe, an air pump and a CO2 analyzer, the sampling probe is connected to the inlet of the air pump through a sampling pipeline, and a sampling valve, a filter and a condenser are installed on the pipeline, and a vent pipeline and a measuring pipeline are connected to the outlet of the air pump at the same time, the measuring pipeline is connected to the air inlet of the CO2 analyzer, and a filter and a condenser are installed on the measuring pipeline, and the exhaust port of the CO2 analyzer is connected to another vent pipeline; it also includes a half-range calibration pipeline and a full-range calibration pipeline, one end of the half-range calibration pipeline is connected to a reversing solenoid valve arranged on the measuring pipeline, one end of the full-range calibration pipeline is connected to the sampling pipeline, and the other ends of the standard gas supply pipeline, the half-range calibration pipeline and the full-range calibration pipeline are connected through a manual reversing valve; it also includes a backflush pipeline, the backflush pipeline is connected between the sampling probe and the sampling valve on the sampling pipeline, and a backflush valve is installed on the backflush pipeline.

[0007] Preferably, it also includes a probe box and a cabinet; the sampling probe, sampling valve and back-blowing valve are arranged in the probe box, a sleeve for connecting to the exhaust pipe is provided on the probe box and the sampling probe is located in the sleeve, and a back-blowing gas source interface is provided on the probe box; the vacuum pump, CO2 analyzer, filter and condenser are arranged in the cabinet, and the cabinet is provided with an inlet, a vent and a standard gas source interface.

[0008] Preferably, a heating pipeline is installed on the sampling pipeline between the probe box and the cabinet, and the sample gas output from the probe box is transported to the cabinet in a manner of full-process heating.

[0009] Preferably, the filter on the sampling pipeline is a dust removal filter, the filter on the measuring pipeline includes a dust removal filter and a hydrophobic filter, the reversing solenoid valve is located between the condenser and the dust removal filter on the measuring pipeline, and also includes a humidity alarm connected to the dust removal filter.

[0010] Preferably, a hygrometer is installed between the filter and the condenser on the sampling pipeline, and a pressure switch is installed between the condenser and the vacuum pump on the sampling pipeline.

[0011] Preferably, a flow meter is installed on the venting pipeline connected to the vacuum pump, and a flow meter is installed on the measuring pipeline and on the pipeline between the hydrophobic filter and the CO2 analyzer.

[0012] Preferably, a water collecting tank is further provided in the cabinet, the water outlets of the sampling pipeline and the condensers on the measuring pipeline are connected to the water collecting tank through pipelines, and a peristaltic pump is installed on the pipelines.

[0013] Preferably, the backblowing pipeline uses compressed air as the backblowing gas source, and a pressure regulating control valve and an air storage tank are also provided in the probe box. The backblowing gas source interface is connected to the pressure regulating control valve through a pipeline, and the pressure regulating control valve is connected to the inlet of the air storage tank through a pipeline. The outlet of the air storage tank is connected to the backblowing valve through a pipeline, and a drain pipe is also connected to the drain outlet of the air storage tank, and a manual ball valve is provided on the drain pipe.

[0014] The advantages and positive effects of the utility model are:

[0015] The present invention provides a high-concentration carbon dioxide online continuous monitoring system. Compared with existing carbon dioxide monitoring systems, the monitoring system of the present invention is provided with a backflush pipeline, which uses a backflush gas source to backflush and clean the sampling probe, remove sediments in the sampling probe, solve the problem of clogging the sampling probe, and keep the collected sample gas volume stable, which is conducive to ensuring the accuracy of CO2 concentration measurement. The monitoring system of the present invention is provided with a half-range calibration pipeline and a full-range calibration pipeline, and uses a manual reversing valve and a reversing solenoid valve to control the on and off of the calibration pipeline. When the half-range calibration pipeline is open, the standard gas is passed through the measurement pipeline where the CO2 analyzer is located. When the full-range calibration pipeline is open, the standard gas is passed through the full-process pipeline. The accuracy of CO2 concentration measurement is ensured by applying necessary calibration operations to the CO2 analyzer.

[0016] By setting up sampling valves, back-blowing valves and reversing solenoid valves, etc., this system is allowed to adopt changes in control paths such as the pre-processing control center and industrial computer, so that this monitoring system can controllably realize multiple functions such as sampling analysis, calibration, and pipeline cleaning. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic diagram of the system structure of the utility model;

[0018] Figure 2 It is a schematic diagram of the application state of the utility model. DETAILED DESCRIPTION

[0019] In order to further understand the content, features and effects of the present invention, the following embodiments are given to illustrate in detail.

[0020] See Figure 1 The present invention provides a high-concentration online continuous carbon dioxide monitoring system, comprising a probe box and a cabinet. The probe box and its accessories are attached to the exhaust duct to sample the exhaust gas, obtaining a gas sample. The cabinet and its accessories receive the sample gas from the probe box and measure the CO2 concentration in the sample gas.

[0021] Based on the flow direction of the sample gas, this online continuous monitoring system includes a sampling probe, an air pump, and a CO2 analyzer. The sampling probe is connected to the inlet of the air pump via a sampling pipeline, and the outlet of the air pump is connected to the inlet of the CO2 analyzer via a measuring pipeline. The sampling probe is tubular and is used to obtain sample gas from the exhaust pipe. The air pump is used to provide the flow of the sample gas. The sample gas eventually enters the CO2 analyzer for processing and measurement of the CO2 concentration. The CO2 analyzer is a prior art, and its structure, function, and principle are not described in detail here.

[0022] A sampling valve, a filter and a condenser are installed on the sampling pipeline. The sampling valve is an electrically controlled valve used to control the on-off connection between the sampling probe and the sampling pipeline. The filter is selected as a dust removal filter to filter and intercept dust particles in the sample gas. The condenser is used to condense and dehydrate the sample gas, remove water vapor in the sample gas and make it dry.

[0023] In this embodiment, a hygrometer is installed between the filter and the condenser on the sampling pipeline, and a pressure switch is installed between the condenser and the vacuum pump on the sampling pipeline. The hygrometer is used to measure the humidity value of the passing sample gas, and the pressure switch is used to measure the pressure value of the passing sample gas.

[0024] As shown in the figure, the probe box in this embodiment comprises a sealed, insulated enclosure. The sampling probe and sampling valve are housed within the probe box. A sleeve is provided on the probe box for connection to the exhaust duct, and the sampling probe is located within this sleeve. When the probe box is installed in the exhaust duct, the sleeve is inserted into a pre-determined monitoring port on the duct, allowing the sampling probe to draw exhaust gas from within the duct for sampling.

[0025] This online continuous monitoring system uses backflushing to clean the inside of the sampling probe. Backflushing removes sediments inside the sampling probe, keeps the inside of the sampling probe clean, solves the problem of sampling probe blockage, restores the effective inner diameter of the sampling probe, and keeps the collected sample gas volume stable, thereby ensuring the accuracy of CO2 concentration measurement.

[0026] As shown in the figure, the backblowing means used include a backblowing pipeline, which is connected between the sampling probe and the sampling valve on the sampling pipeline. A backblowing valve is installed on the backblowing pipeline. The backblowing pipeline uses compressed air as the backblowing gas source. A backblowing gas source interface is provided on the probe box. The external compressed air pipeline is connected to the backblowing gas source interface. The backblowing valve is used to control the on and off of the backblowing pipeline. The backblowing valve is an electrically controlled valve.

[0027] In this embodiment, a pressure regulating control valve and an air tank are also provided in the probe box. The back-blowing air source interface is connected to the pressure regulating control valve via a pipeline. The pressure regulating control valve is connected to the inlet of the air tank via a pipeline. The outlet of the air tank is connected to the back-blowing valve via a pipeline. A drain pipe is also connected to the drain outlet of the air tank and a manual ball valve is provided on the drain pipe. The pressure regulating control valve is used to set the back-blowing pressure of the compressed air for back-blowing. The air tank is used to buffer the pressure and remove condensed water at the same time. The dry compressed air source eventually enters the sampling pipeline under the control of the back-blowing valve. At this time, the sampling valve is closed, and the compressed air passes through the sampling probe in the opposite direction to achieve air cleaning inside the sampling probe. The cleaned exhaust gas enters the exhaust channel. The internal condensed water is discharged by opening the manual valve on the drain pipe of the air tank.

[0028] The outlet of the vacuum pump is connected to both a vent line and a measurement line. The measurement line is connected to the air inlet of the CO2 analyzer and is equipped with a filter and a condenser. The exhaust port of the CO2 analyzer is connected to another vent line. The vent line directly connected to the outlet of the vacuum pump is used to discharge a portion of the sample gas directly to the outside of the cabinet. A flow meter is installed on this vent line. Another vent line is used to discharge the sample gas after the CO2 concentration measurement is completed. Therefore, in this embodiment, two vent ports are installed on the cabinet, and the two vent lines inside the cabinet are connected to these two vent ports respectively.

[0029] The filter is used to further filter the sample gas, and the condenser is used to further remove water vapor from the sample gas and further dry it. In this embodiment, the filter on the measurement pipeline includes a dust removal filter and a hydrophobic filter, wherein the dust removal filter is used to further remove particulate matter from the sample gas, and the hydrophobic filter is used to further remove moisture. The sample gas discharged through the hydrophobic filter has been fully free of particulate matter and water vapor, resulting in a sufficiently clean sample gas that meets the concentration measurement requirements of the CO2 analyzer. In this embodiment, a flow meter is installed on the measurement pipeline, between the hydrophobic filter and the CO2 analyzer, for measuring the flow value.

[0030] In this embodiment, a water collecting tank is also provided in the cabinet. The water outlets of the condensers on the sampling pipeline and the measuring pipeline are connected to the water collecting tank through pipelines, and a peristaltic pump is installed on the pipeline. When the peristaltic pump works, the condensed water generated by the condenser is sent into the water collecting tank for storage.

[0031] The vacuum pump, CO2 analyzer, the in-cabinet portion of the sampling line, the measuring line, and its accessories (filter and condenser) are installed inside the cabinet. To better transport the sample gas, a heating line is installed on the sampling line between the probe box and the cabinet. The sample gas output from the probe box is transported to the cabinet with heating throughout the entire process. Furthermore, the cabinet is equipped with a sampling port, to which the in-cabinet portion of the sampling line is connected, and the out-cabinet portion of the sampling line is connected.

[0032] It also includes a half-range calibration pipeline and a full-range calibration pipeline. The half-range calibration pipeline transports standard gas (that is, calibration gas) to the measuring pipeline where the CO2 analyzer is located in the cabinet, and the full-range calibration pipeline transports standard gas to the entire passage. When the standard gas passes through the CO2 analyzer, the calibration procedure of the CO2 analyzer is executed to complete the calibration operation of the CO2 analyzer and improve the accuracy of CO2 concentration measurement.

[0033] One end of the half-range calibration pipeline is connected to the reversing solenoid valve arranged on the measuring pipeline, one end of the full-range calibration pipeline is connected to the sampling pipeline, and the other ends of the standard gas supply pipeline, the half-range calibration pipeline and the full-range calibration pipeline are connected through a manual reversing valve. The reversing solenoid valve is used to control the connection and disconnection of the pipeline by electronic control, and the manual reversing valve is used to control the connection and disconnection of the pipeline manually.

[0034] In this embodiment, the reversing solenoid valve is located between the condenser and the dust removal filter on the measuring pipeline, and also includes a humidity alarm connected to the dust removal filter. The humidity alarm is used to detect the humidity value of the sample gas and generate an alarm when the humidity value exceeds the standard. The sample gas with excessive humidity will cause the CO2 concentration measurement to fail.

[0035] In this embodiment, a standard gas source interface is provided on the cabinet, which improves the convenience of connecting the standard gas supply pipeline to the system.

[0036] How to run:

[0037] Figure 2 The following diagram shows the application state of this online continuous monitoring system. It shows that the CO2 analyzer sends digital signals to the industrial computer (measurement data) and provides control signals to the preprocessing control center (operating status, operation signals). The industrial computer receives digital signals from the CO2 analyzer and the preprocessing control center, displays, analyzes, and stores the data. The industrial computer provides control signals to the preprocessing control center (operating status, operation signals). The preprocessing control center can control the operation of the sampling valve, backflush valve, vacuum pump, and reversing solenoid valve 1.

[0038] Connect the standard gas supply pipeline to the standard gas source interface, connect the compressed air supply pipeline to the back-blowing gas source interface, and correctly install the probe box to the preset monitoring interface on the exhaust pipe;

[0039] When the system performs half-range calibration: a manual reversing valve is used to connect the standard gas supply pipeline with the half-range calibration pipeline, and the reversing solenoid valve is switched to the half-range calibration channel, that is, the half-range calibration pipeline is connected with the measuring pipeline; at this time, the vacuum pump stops working, and the standard gas is connected through the standard gas source interface. The standard gas passes through the manual reversing valve and the reversing solenoid valve, flows through the filter and hydrophobic filter on the measuring pipeline, and enters the CO2 analyzer through the adjustment of the flow meter. The calibration operation is performed on the CO2 analyzer to complete the calibration of the CO2 analyzer.

[0040] When the system is fully calibrated: a manual reversing valve is used to connect the standard gas supply pipeline with the full calibration pipeline, the standard gas is connected through the standard gas source interface, the sampling valve is closed, and the vacuum pump draws the standard gas through the full calibration pipeline and the sampling pipeline. The standard gas enters the sampling port for heating through the heating pipeline, and the standard gas enters the cabinet. The dust and other particulate matter are removed by the filter on the sampling pipeline, and then enters the hygrometer for humidity measurement. It enters the condenser for cooling and water removal. At the same time, the peristaltic pump works to take away the condensed water and discharge it into the water collection tank. The treated standard gas is pressure-measured through a pressure switch and is divided into two paths after passing through a vacuum pump. One path is adjusted by a flow meter to enter the vent pipeline and is discharged from the vent port. The other path is adjusted by a flow meter to enter the condenser on the measuring pipeline for secondary cooling and water removal. The peristaltic pump works to discharge the condensed water into the water collection tank, and the reversing solenoid valve switches the path. The standard gas is dust-removed and humidity monitored (humidity exceeds the standard alarm) through the filter on the measuring pipeline. After that, it continues to be dehumidified through the hydrophobic filter and enters the CO2 analyzer and is discharged from the vent port.

[0041] When the system performs backflush operation: the vacuum pump stops working, the sampling valve is closed, compressed air enters from the backflush air source interface, the pressure regulating controller adjusts the pressure, the backflush valve is opened, and compressed air backflushes the sampling probe to remove internal sediment.

Claims

1. A high-concentration carbon dioxide online continuous monitoring system, characterized by: It includes a sampling probe, an air pump and a CO2 analyzer. The sampling probe is connected to the inlet of the air pump through a sampling pipeline, and a sampling valve, a filter and a condenser are installed on the pipeline. The outlet of the air pump is connected to a vent pipeline and a measuring pipeline at the same time. The measuring pipeline is connected to the air inlet of the CO2 analyzer, and a filter and a condenser are installed on the measuring pipeline. The exhaust port of the CO2 analyzer is connected to another vent pipeline; it also includes a half-range calibration pipeline and a full-range calibration pipeline. One end of the half-range calibration pipeline is connected to a reversing solenoid valve arranged on the measuring pipeline, and one end of the full-range calibration pipeline is connected to the sampling pipeline. The other ends of the standard gas supply pipeline, the half-range calibration pipeline and the full-range calibration pipeline are connected through a manual reversing valve; it also includes a backflush pipeline. The backflush pipeline is connected between the sampling probe and the sampling valve on the sampling pipeline, and a backflush valve is installed on the backflush pipeline.

2. The high-concentration carbon dioxide online continuous monitoring system according to claim 1, characterized in that: It also includes a probe box and a cabinet; the sampling probe, sampling valve and back-blowing valve are arranged in the probe box, the probe box is provided with a sleeve for connecting to the exhaust pipe and the sampling probe is located in the sleeve, and the probe box is provided with a back-blowing gas source interface; the vacuum pump, CO2 analyzer, filter and condenser are arranged in the cabinet, and the cabinet is provided with an inlet, a vent and a standard gas source interface.

3. The high concentration carbon dioxide online continuous monitoring system as claimed in claim 2, characterized in that: A heating pipeline is installed on the sampling pipeline between the probe box and the cabinet, and the sample gas output from the probe box is transported to the cabinet in a fully heated manner.

4. The high-concentration carbon dioxide online continuous monitoring system according to claim 3, characterized in that: The filter on the sampling pipeline is a dust removal filter, and the filters on the measuring pipeline include a dust removal filter and a hydrophobic filter. The reversing solenoid valve is located between the condenser and the dust removal filter on the measuring pipeline, and also includes a humidity alarm connected to the dust removal filter.

5. The high-concentration carbon dioxide online continuous monitoring system according to claim 4, characterized in that: A hygrometer is installed between the filter and the condenser on the sampling pipeline, and a pressure switch is installed between the condenser and the vacuum pump on the sampling pipeline.

6. The high concentration carbon dioxide online continuous monitoring system as claimed in claim 5, characterized in that: A flow meter is installed on the venting pipeline connected to the vacuum pump, and a flow meter is installed on the measuring pipeline and the pipeline between the hydrophobic filter and the CO2 analyzer.

7. The high-concentration carbon dioxide online continuous monitoring system according to claim 6, characterized in that: A water collecting tank is also provided in the cabinet. The water outlets of the condensers on the sampling pipeline and the measuring pipeline are connected to the water collecting tank through pipelines, and a peristaltic pump is installed on the pipelines.

8. The high-concentration carbon dioxide online continuous monitoring system according to claim 7, characterized in that: The backblowing pipeline uses compressed air as the backblowing gas source. A pressure regulating control valve and an air storage tank are also provided in the probe box. The backblowing gas source interface is connected to the pressure regulating control valve through a pipeline. The pressure regulating control valve is connected to the inlet of the air storage tank through a pipeline. The outlet of the air storage tank is connected to the backblowing valve through a pipeline. A drain pipe is also connected to the drain outlet of the air storage tank and a manual ball valve is provided on the drain pipe.

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