Single-tube flue gas CO2 concentration measuring probe based on multi-point dynamic pressure mixed sampling

Abstract

The utility model discloses a single-tube flue gas CO2 concentration measuring probe based on multi-point dynamic pressure mixed sampling. The single-tube flue gas CO2 concentration measuring probe comprises a single-tube flue gas sampling tube and a CO2 concentration pretreatment measuring probe, the pipe diameter D of the single-pipe type flue gas sampling pipe is larger than or equal to DN65, the single-pipe type flue gas sampling pipe is located in the flue, and the two ends of the single-pipe type flue gas sampling pipe are fixed to the flue wall The CO2 concentration measuring probe is mounted outside the flue, and the sampling end of the CO2 concentration measuring probe extends into the single-tube flue gas sampling tube in the flue; a back airflow exhaust port and a plurality of upstream airflow sampling ports are formed in the single-tube flue gas sampling tube, the back airflow exhaust port is higher than each upstream airflow sampling port, and the sampling end of the CO2 concentration pretreatment probe is located between the back airflow exhaust port and the upstream airflow sampling port closest to the back airflow exhaust port; and at least one water outlet is formed in the bottom of the single-pipe type flue gas sampling pipe in the flue. The device not only ensures the representativeness of the taken sample, but also improves the stability, and is simple, reliable and low in cost.

Description

Technical Field

[0001] The utility model relates to a single-tube flue gas CO2 concentration measuring probe based on multi-point dynamic pressure mixed sampling, belonging to the technical field of fixed source carbon emission monitoring. Background Art

[0002] Modern industrial production inevitably releases pollutants into the atmosphere, with large quantities emitted through flues, chimneys, and exhaust pipes. To calculate the total amount of pollutant emissions, flue gas flow and pollutant concentration measurement equipment is typically installed on these flues, chimneys, and exhaust pipes.

[0003] Currently, internationally recognized methods for quantifying CO2 emissions from coal combustion can be divided into the carbon balance method, the emission factor method, and the direct monitoring method. The carbon balance method requires relatively complete basic production records, but the statistical foundation of Chinese enterprises currently struggles to fully meet these requirements. The emission factor method, due to its simplicity, high authority, and widespread application, has been adopted in relevant Chinese greenhouse gas inventory compilation guidelines and greenhouse gas emission accounting and reporting guidelines. However, it suffers from issues such as low accuracy, inefficient data collection methods, and significant timeliness lags. The direct monitoring method is favored due to its advantages such as simple measurement, efficient data collection, and minimal human interference.

[0004] The reliability and accuracy of online carbon emission monitoring are key to determining its role in greenhouse gas emission source monitoring capacity building. For large coal-fired power generation units, flue gas generally must pass through a wet desulfurization device before being discharged. The desulfurization slurry is sprayed in a large space. Since spraying is difficult to achieve completely uniformity, the flue gas temperature, flow rate, and desulfurization reaction intensity in different areas are not exactly the same. The CO2 concentration emitted during the wet desulfurization process will also be uneven. Therefore, monitoring the CO2 concentration at a single point at the flue gas outlet downstream of the desulfurization device may result in large uncertainties. To improve the accuracy of CO2 concentration measurement, multi-point sampling measurement can be used, but traditional multi-point sampling devices have problems such as high cost and low reliability. Utility Model Content

[0005] In order to solve the above existing problems, the utility model provides a single-tube flue gas CO2 concentration measurement probe based on multi-point dynamic pressure mixed sampling, which has the advantages of low cost and high reliability.

[0006] In order to solve the above technical problems, the technical solutions adopted by the present invention are as follows:

[0007] A single-tube flue gas CO2 concentration measuring probe based on multi-point dynamic pressure mixed sampling, comprising a single-tube flue gas sampling tube and a CO2 concentration pretreatment measuring probe;

[0008] The diameter D of the single-tube flue gas sampling tube shall not be less than DN65. The single-tube flue gas sampling tube shall be located in the flue, and both ends of the single-tube flue gas sampling tube shall be fixed to the flue wall. The CO2 concentration measuring probe shall be installed outside the flue, and the sampling end of the CO2 concentration measuring probe shall extend into the single-tube flue gas sampling tube in the flue.

[0009] The single-tube flue gas sampling tube in the flue is provided with 3-12 upstream airflow sampling ports and at least one downstream airflow exhaust port. The upstream airflow sampling ports are arranged at equal intervals along the height direction. The downstream airflow exhaust port is set at a position higher than the setting position of each upstream airflow sampling port. The distance between the downstream airflow exhaust port and the nearest upstream airflow sampling port is not less than 10 cm. The sampling end of the CO2 concentration pretreatment probe is located between the downstream airflow exhaust port and the nearest upstream airflow sampling port.

[0010] At least one drainage port is provided at the bottom of the single-tube flue gas sampling tube in the flue.

[0011] The above-mentioned “interval between the backflow exhaust port and the upstream airflow sampling port closest thereto” refers to the interval between the backflow exhaust port and the upstream airflow sampling port closest thereto.

[0012] The above-mentioned upstream airflow sampling port refers to the sampling port arranged on the upstream airflow side of the single-tube flue gas sampling tube. The backflow exhaust port refers to the exhaust port arranged on the backflow side of the single-tube flue gas sampling tube.

[0013] This application adopts a single-tube flue gas sampling tube for sampling. Both ends of the single-tube flue gas sampling tube are fixed on the flue wall. The tube diameter D is not less than DN65, and multiple sampling ports are evenly arranged on the upstream airflow side. The flue gas taken from each sampling port can be fully mixed in the single-tube flue gas sampling tube, which not only ensures the representativeness of the sample taken, but also improves the stability. It has a simple structure, low cost, and high reliability; it is not easy to clog and is easy to maintain; at the same time, it is convenient for the discharge of condensed water in the single-tube flue gas sampling tube.

[0014] To improve the uniformity of multi-point mixing and minimize the corrosion or damage of the CO2 concentration pretreatment measurement probe, the above-mentioned single-tube flue gas CO2 concentration measurement probe based on multi-point dynamic pressure mixing sampling also includes a porous heating device. The porous heating device is installed in the single-tube flue gas sampling tube and is located between the backflow exhaust port and the upstream airflow sampling port closest to it (the backflow exhaust port). The heating temperature is set at 80-200°C. This can reduce or avoid the deposition of corrosive gases and promote the improvement of uniformity.

[0015] In order to meet the drainage needs of general working conditions and at the same time weaken the influence of the drainage outlet on the uniformity of multi-point mixed sampling, two drainage outlets are provided at the bottom of the single-tube flue gas sampling tube in the above-mentioned flue, namely the first drainage outlet and the second drainage outlet. The first drainage outlet and the second drainage outlet are located at the bottom of each upstream airflow sampling outlet. The first drainage outlet is set upstream of the airflow and the second drainage outlet is set away from the airflow.

[0016] The first drain outlet and the second drain outlet are both circular holes with the same size, and the hole diameter is (1 / 20-1 / 5)D.

[0017] In order to increase the flue gas sampling update speed and facilitate processing, the upstream airflow sampling port is preferably a circular hole, the aperture is preferably 1 / 10D to 1 / 2D, and the upstream airflow sampling ports are of the same size (ie, equal in size).

[0018] In order to ensure structural strength and facilitate processing, the backflow exhaust port is preferably an elliptical hole, and the total cross-sectional area of ​​the backflow exhaust port (the sum of the cross-sectional areas of all backflow exhaust ports) is larger than the total cross-sectional area of ​​the upflow sampling port (the sum of the cross-sectional areas of all upflow sampling ports).

[0019] In order to improve the representativeness of the sampling, it is further preferred that the total cross-sectional area of ​​the backflow exhaust port is 1 to 1.5 times the cross-sectional area of ​​the flue gas sampling tube.

[0020] In order to ensure structural strength and reduce smoke flow resistance, the diameter D of the single-tube smoke sampling tube is preferably DN100~DN150.

[0021] In order to meet the sampling requirements under general working conditions, it is preferred that the single-tube flue gas sampling tube in the flue has 4-6 upstream airflow sampling ports and 1 downstream airflow exhaust port.

[0022] In order to facilitate installation, the top of the single-tube flue gas sampling tube passes through the flue, and the CO2 concentration measuring probe is installed on the top of the single-tube flue gas sampling tube.

[0023] In order to facilitate manual inspection of whether there is blockage in the upstream air sampling port and the downstream air exhaust port, a pedal plate is provided on the outer wall of the flue gas sampling tube along the height direction. Each pedal plate is arranged in the downstream direction, and the interval between adjacent pedal plates is 25 to 50 cm.

[0024] The CO2 concentration pretreatment measurement probe, porous heating device and other components of this application can directly use existing equipment.

[0025] The technologies not mentioned in this utility model are all referred to the existing technology.

[0026] The utility model discloses a single-tube flue gas CO2 concentration measuring probe based on multi-point dynamic pressure mixed sampling, which adopts a single-tube flue gas sampling tube for sampling. Both ends of the single-tube flue gas sampling tube are fixed on the flue wall, and multiple sampling ports are evenly arranged on the airflow side. The tube diameter D is not less than DN65, which not only ensures the representativeness of the sample taken, but also improves the stability. The structure is simple, only one pipeline is required, the cost is low, and the reliability is high. It is not easy to be blocked and is easy to maintain. At the same time, it is convenient for the discharge of condensed water in the single-tube flue gas sampling tube. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 This is a structural schematic diagram of a single-tube flue gas CO2 concentration measuring probe based on multi-point dynamic pressure mixed sampling in Example 1 of the present utility model;

[0028] Figure 2 This is a schematic structural diagram of a single-tube flue gas CO2 concentration measuring probe based on multi-point dynamic pressure mixed sampling in Example 2 of the present utility model;

[0029] Figure 3 This is a schematic structural diagram of a single-tube flue gas CO2 concentration measuring probe based on multi-point dynamic pressure mixed sampling in Example 3 of the present utility model;

[0030] Figure 4 This is a schematic structural diagram of a single-tube flue gas CO2 concentration measuring probe based on multi-point dynamic pressure mixed sampling in Example 4 of the present utility model;

[0031] In the figure, 1 is the flue, 2 is the CO2 concentration pretreatment measurement probe, 3 is the flue gas sampling tube, 4 is the upstream airflow sampling port, 5 is the downstream airflow exhaust port, 6 is the first drain port, 7 is the second drain port, 8 is the porous heating device, 9 is the pedal plate, and 10 is the airflow direction. DETAILED DESCRIPTION

[0032] In order to better understand the present invention, the content of the present invention is further explained below in conjunction with the embodiments, but the content of the present invention is not limited to the following embodiments.

[0033] The directional words such as up and down, left and right, horizontal, vertical, top and bottom, inside and outside in this application are all based on the relative directions or positional relationships shown in the drawings and should not be understood as absolute limitations on this application.

[0034] Example 1

[0035] like Figure 1 As shown, a single-tube flue gas CO2 concentration measurement probe based on multi-point dynamic pressure mixing sampling includes a single-tube flue gas sampling tube and a CO2 concentration pretreatment measurement probe;

[0036] The diameter D of the single-tube flue gas sampling tube shall not be less than DN65. The single-tube flue gas sampling tube shall be located in the flue, and both ends of the single-tube flue gas sampling tube shall be fixed to the flue wall. The CO2 concentration measuring probe shall be installed outside the flue, and the sampling end of the CO2 concentration measuring probe shall extend into the single-tube flue gas sampling tube in the flue.

[0037] The single-tube flue gas sampling tube in the flue is provided with four upstream airflow sampling ports and one backflow exhaust port. The upstream airflow sampling ports are arranged at equal intervals along the height direction. The backflow exhaust port is set at a higher position than the upstream airflow sampling ports. The interval between the backflow exhaust port and the nearest upstream airflow sampling port is not less than 10 cm. The sampling end of the CO2 concentration pretreatment probe is located between the backflow exhaust port and the nearest upstream airflow sampling port.

[0038] Example 2

[0039] On the basis of Example 1, the following improvements were made: Figure 2 As shown, a first drain port and a second drain port are provided at the bottom of the single-tube flue gas sampling tube in the flue. The first drain port and the second drain port are located at the bottom of each upstream airflow sampling port. The first drain port is provided upstream of the airflow and the second drain port is provided away from the airflow.

[0040] The above-mentioned single-tube flue gas sampling tube is used for sampling. Both ends of the single-tube flue gas sampling tube are fixed on the flue wall. The tube diameter D is not less than DN65, and multiple sampling ports are evenly arranged on the airflow side. The flue gas taken from each sampling port can be fully mixed in the single-tube flue gas sampling tube, which not only ensures the representativeness of the sample taken, but also improves the stability. It has a simple structure, low cost, and high reliability; it is not easy to clog and is easy to maintain; at the same time, it is convenient to discharge condensed water in the single-tube flue gas sampling tube.

[0041] Example 3

[0042] On the basis of Example 2, the following improvements were made: Figure 3 As shown, in order to improve the uniformity of multi-point mixing and minimize the corrosion or damage of the CO2 concentration pretreatment measurement probe, the single-tube flue gas CO2 concentration measurement probe based on multi-point dynamic pressure mixing sampling also includes a porous heating device. The porous heating device is installed in the single-tube flue gas sampling tube and is located between the backflow exhaust port and the upstream airflow sampling port closest to it (the backflow exhaust port). The heating temperature is set at 80-200°C. This can reduce or avoid the deposition of corrosive gases and promote the improvement of uniformity.

[0043] Example 4

[0044] On the basis of Example 3, the following improvements were made: Figure 4As shown, in order to facilitate manual inspection of whether there are problems such as blockage in the upstream air sampling port and the downstream air exhaust port, a pedal plate is arranged along the height direction on the outer wall of the flue gas sampling tube. Each pedal plate is arranged in the downstream direction, and the interval between adjacent pedal plates is 25 to 50 cm.

[0045] Example 5

[0046] On the basis of Example 4, the following improvements were made: Figure 1-4 As shown, for ease of installation, the top of the single-tube flue gas sampling tube extends out of the flue, and the CO2 concentration measurement probe is installed on top of the single-tube flue gas sampling tube. In this example, the diameter D of the single-tube flue gas sampling tube is DN120 (nominal diameter 120 mm) (in practice, DN100, DN150, etc. can also be used). The single-tube flue gas sampling tube in the flue has four upstream gas sampling ports and one downstream gas exhaust port. Each upstream gas sampling port is a circular hole of equal size, with a diameter of 24 mm. The downstream gas exhaust port is an elliptical hole, with a total cross-sectional area larger than that of each upstream gas sampling port, which is 1.2 times the cross-sectional area of ​​the flue gas sampling tube. The first and second drain ports are both circular holes of the same size, with a diameter of (1 / 6) D. This device has been used in a boiler flue and has been operating continuously for 18 months without any problems or blockages, demonstrating stability and reliability.

[0047] The single-tube flue gas CO2 concentration measurement probe based on multi-point dynamic pressure mixing sampling in the above examples adopts a single-tube flue gas sampling tube for sampling. Both ends of the single-tube flue gas sampling tube are fixed on the flue wall, and multiple sampling ports are evenly arranged on the oncoming airflow side. The tube diameter D is not less than DN65, which not only ensures the representativeness of the samples taken, but also improves the stability. It has a simple structure, requires only one pipeline, is low in cost, and has high reliability. It is not easy to clog and is easy to maintain. At the same time, it is convenient for the discharge of condensed water in the single-tube flue gas sampling tube.

Claims

1. A single-tube flue gas CO2 concentration measurement probe based on multi-point dynamic pressure mixed sampling, characterized by: It includes a single-tube flue gas sampling tube (3) and a CO2 concentration pretreatment measurement probe (2); The diameter D of the single-tube flue gas sampling tube (3) is not less than DN65, the single-tube flue gas sampling tube (3) is located in the flue (1), and both ends of the single-tube flue gas sampling tube (3) are fixed to the wall of the flue (1); the CO2 concentration measuring probe is installed outside the flue (1), and the sampling end of the CO2 concentration measuring probe extends into the single-tube flue gas sampling tube (3) in the flue (1); A single-tube flue gas sampling tube (3) in a flue (1) is provided with 3-12 upstream airflow sampling ports (4) and at least one downstream airflow exhaust port (5), the upstream airflow sampling ports (4) are arranged at equal intervals along the height direction, the downstream airflow exhaust port (5) is arranged at a position higher than the arrangement position of each upstream airflow sampling port (4), the distance between the downstream airflow exhaust port (5) and the upstream airflow sampling port (4) closest thereto is not less than 10 cm, and the sampling end of the CO2 concentration pretreatment probe is located between the downstream airflow exhaust port (5) and the upstream airflow sampling port (4) closest thereto; The bottom of the single-tube flue gas sampling tube (3) in the flue (1) is provided with at least one drainage port.

2. The single-tube flue gas CO2 concentration measuring probe based on multi-point dynamic pressure mixed sampling according to claim 1 is characterized in that: It also includes a porous heating device (8), which is arranged in the single-tube flue gas sampling tube (3) and located between the backflow exhaust port (5) and the frontflow sampling port (4) closest to it.

3. The single-tube flue gas CO2 concentration measuring probe based on multi-point dynamic pressure mixed sampling according to claim 1 or 2, characterized in that: Two drainage ports are provided at the bottom of the single-tube flue gas sampling tube (3) in the flue (1), namely a first drainage port (6) and a second drainage port (7). The first drainage port (6) and the second drainage port (7) are located at the bottom of each upstream airflow sampling port (4). The first drainage port (6) is provided upstream of the airflow, and the second drainage port (7) is provided away from the airflow.

4. The single-tube flue gas CO2 concentration measuring probe based on multi-point dynamic pressure mixed sampling according to claim 3 is characterized in that: The first drain port (6) and the second drain port (7) are both circular holes with the same size, and the apertures of the first drain port (6) and the second drain port (7) are both (1 / 20-1 / 5)D.

5. The single-tube flue gas CO2 concentration measuring probe based on multi-point dynamic pressure mixed sampling according to claim 1 or 2, characterized in that: The upstream airflow sampling port (4) is a circular hole with a hole diameter of 1 / 10D to 1 / 2D, and the sizes of the upstream airflow sampling ports (4) are consistent.

6. The single-tube flue gas CO2 concentration measuring probe based on multi-point dynamic pressure mixed sampling according to claim 1 or 2, characterized in that: The backflow exhaust port (5) is an elliptical hole, and the total cross-sectional area of ​​the backflow exhaust port (5) is larger than the total cross-sectional area of ​​the frontflow sampling port (4).

7. The single-tube flue gas CO2 concentration measuring probe based on multi-point dynamic pressure mixed sampling according to claim 1 or 2, characterized in that: The total cross-sectional area of ​​the backflow exhaust port (5) is 1 to 1.5 times the cross-sectional area of ​​the smoke sampling tube (3).

8. The single-tube flue gas CO2 concentration measuring probe based on multi-point dynamic pressure mixed sampling according to claim 1 or 2, characterized in that: The diameter D of the single-tube flue gas sampling tube (3) is DN100-DN150; the single-tube flue gas sampling tube (3) in the flue (1) has 4-6 upstream airflow sampling ports (4) and one downstream airflow exhaust port (5).

9. The single-tube flue gas CO2 concentration measuring probe based on multi-point dynamic pressure mixed sampling according to claim 1 or 2, characterized in that: The top of the single-tube flue gas sampling tube (3) passes through the flue (1), and the CO2 concentration measuring probe is installed on the top of the single-tube flue gas sampling tube (3).

10. The single-tube flue gas CO2 concentration measuring probe based on multi-point dynamic pressure mixed sampling according to claim 1 or 2, characterized in that: The outer wall of the smoke sampling tube (3) is also provided with a pedal plate (9) arranged in the height direction. Each pedal plate (9) is arranged with its back to the airflow, and the interval between two adjacent pedal plates (9) is 25 to 50 cm.

Images