Flue gas sampling device and flue gas testing system

Abstract

The application discloses a flue gas sampling device and a flue gas testing system, and belongs to the field of flue gas sampling. The flue gas sampling device comprises: a front-end sampling assembly located at the front end of the sampling device and provided with a flue gas input port, which comprises: a first inner pipe, a first outer protective pipe and a cap; wherein the first outer protective pipe is sleeved outside the first inner pipe and a first air suction channel is formed between the first inner pipe and the first outer protective pipe; the inside space of the first inner pipe forms a second air suction channel; the cap is fixedly connected to the front end of the first inner pipe; a first annular channel is formed between the outer wall of the cap and the first outer protective pipe; a second annular channel is formed between the inner wall of the cap and the first inner pipe; a suction hole is formed in the pipe wall of the first inner pipe, and the suction hole is located in the inside region of the cap. The application solves the problems that the existing moisture content sampling device sucks the condensed liquid drops together when sucking the flue gas, and that the high-temperature heat tracing changes the flue gas water vapor content in the flue.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of flue gas sampling, in particular to a flue gas sampling device for measuring the moisture content of condensed flue gas and a testing system. BACKGROUND

[0002] In recent years, people pay more and more attention to the prevention and control technology of air pollution. The emission of industrial flue gas must strictly comply with the national emission standard. The content of various pollutants in the flue gas is mainly measured by a flue gas analyzer. Therefore, the accuracy of sample collection directly affects the detection accuracy, and further affects the normal operation of the entire factory waste gas emission system.

[0003] At present, the moisture content tester is usually used for testing the moisture content of flue gas in the condensing boiler. The reverse suction device is used to suck the wet flue gas. Under the condition of the same point flue gas heat tracing, the temperature of the wet flue gas is first tested, and then the wet flue gas is heated. The temperature and relative humidity of the heated flue gas are tested by using a humidity-sensitive capacitor, and the moisture content of the flue gas is calculated. Since the condensate droplets are contained in the flue gas of the condensing boiler, although a part of the droplets is filtered out by using the reverse sampling, a small amount of condensate droplets is still sucked into the flue gas by using the suction device, and then vaporized by heating, resulting in inaccurate final measurement of the moisture content. In addition, since high-temperature heat tracing is required at the rear end during the moisture content measurement, the temperature of the outer protective tube is very high when the heat tracing temperature is high. At this time, when sampling is put into the flue, part of the condensate droplets is vaporized, increasing the water vapor content in the flue gas, resulting in that the measured value is inconsistent with the true value. SUMMARY

[0004] The first technical problem to be solved by the present application is that the existing moisture content sampling device sucks the condensate droplets when sucking the flue gas.

[0005] The second technical problem to be solved by the present application is that the outer protective tube of the existing moisture content sampling device has a high temperature, which changes the water vapor content in the flue gas in the flue.

[0006] In view of the above technical problems, the present application provides the following technical scheme:

[0007] A flue gas sampling device, comprising: a front-end sampling assembly located at the front end of the sampling device and having a flue gas input port, which comprises: a first inner tube, a first outer protective tube and a cap; wherein the first outer protective tube is sleeved outside the first inner tube and a first air suction channel is formed between the first inner tube and the first outer protective tube, and a second air suction channel is formed in the inside space of the first inner tube; the cap is fixedly connected to the front end of the first inner tube, a first annular channel is formed between the outer wall of the cap and the first outer protective tube, a second annular channel is formed between the inner wall of the cap and the first inner tube, a suction hole is formed in the wall of the first inner tube, and the suction hole is located in the inside region of the cap.

[0008] In some embodiments of the present application, a suction device is further included, which comprises a first suction pump in communication with the first suction passage and a second suction pump in communication with the second suction passage.

[0009] In some embodiments of the present application, the suction force of the first suction pump is greater than that of the second suction pump.

[0010] In some embodiments of the present application, a rear-end sampling assembly is further included, which is located at the rear end of the sampling device and in communication with the front-end sampling assembly through a connecting assembly; the rear-end sampling assembly comprises: a second inner tube, the inner space of the second inner tube forms a third suction passage and is in communication with the second suction passage of the first inner tube; a heating device is arranged on the outer wall of the second inner tube; a second inner protective tube is sleeved on the second inner tube and connected with the front end of the second inner tube through a connecting assembly; a second outer protective tube is sleeved on the outer side of the second inner protective tube and forms a fourth suction passage therebetween, which is in communication with the first suction passage.

[0011] In some embodiments of the present application, the connecting assembly comprises: an inner connecting sleeve, the front end of the inner connecting sleeve is fixedly connected with the first outer protective tube, and the rear end of the inner connecting sleeve is fixedly connected with the second inner protective tube; a support plate is fixedly connected to the rear end of the inner connecting sleeve, and the front end of the second inner tube is arranged through the support plate; an outer connecting sleeve is sleeved on the outer side of the inner connecting sleeve, the front end of the outer connecting sleeve is fixedly connected with the end of the second inner protective tube, and the rear end of the outer connecting sleeve is fixedly connected with the end of the second outer protective tube.

[0012] In some embodiments of the present application, a connecting passage for connecting the first suction passage and the fourth suction passage is arranged on the inner connecting sleeve, and a communication hole for connecting the first suction passage and the fourth suction passage is arranged on the second inner protective tube.

[0013] In some embodiments of the present application, the rear end of the first inner tube is isolated from the connecting passage of the inner connecting sleeve.

[0014] In some embodiments of the present application, the rear end of the first inner tube is spaced apart from the front end of the second inner tube.

[0015] In some embodiments of the present application, the second outer protective tube is provided with an air outlet interface, which is in communication with the first suction pump.

[0016] The present application also provides a flue gas testing system, which comprises the above flue gas sampling device and a detection device located at the rear end of the flue gas sampling device.

[0017] The technical solution of the present application has the following technical effects compared with the prior art:

[0018] In the flue gas sampling device, the cap is arranged at the front end of the first inner tube to prevent the flue gas from directly entering the first inner tube, so that the flue gas enters the sampling device through the first annular channel between the cap and the first outer protective tube, and then turns back to the second annular channel and enters the first inner tube through the suction hole. The condensate in the flue gas duct is directly discharged to the outside of the sampling device along the first suction channel, and will not be sucked into the second suction channel on the inner side of the first inner tube. The flue gas in the second suction channel does not contain condensate drops, so that the sampling result of the sampling device is more accurate.

[0019] Further, in the flue gas sampling device, a heating device is arranged on the inner side of the second inner tube to realize high-temperature heating of the rear section of the sampling device. The flue gas passes through the fourth suction channel between the second outer protective tube and the second inner protective tube, which can effectively block the heat transfer on the inner side of the second inner tube, so that the temperature of the second outer protective tube is close to the temperature of the flue gas duct, and the influence of high-temperature heating on the water vapor content of the flue gas in the flue gas duct is avoided. BRIEF DESCRIPTION OF DRAWINGS

[0020] The preferred embodiments of the present application will be described in detail below with the help of the accompanying drawings, which will help to understand the purposes and advantages of the present application, in which:

[0021] Figure 1 is a structure schematic view of a specific embodiment of the flue gas sampling device of the present application;

[0022] Figure 2 is a structure schematic view of the front end sampling assembly in a specific embodiment of the flue gas sampling device of the present application;

[0023] Figure 3 is a partial structure schematic view of a specific embodiment of the flue gas sampling device of the present application;

[0024] Figure 4 is a structure schematic view of a specific embodiment of the flue gas testing system of the present application;

[0025] Figure 5 is a partial structure schematic view of another specific embodiment of the flue gas testing system of the present application. EMBODIMENT

[0026] The technical solutions of the present application will be described in detail below with the help of the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0027] In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" and the like indicate the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application. In addition, the terms "first", "second", "third" are only for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0028] In the description of the present application, it should be noted that unless otherwise explicitly specified and limited, the terms "mounting", "connecting", "connecting" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be directly connected, or indirectly connected through an intermediate medium; it can be the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0029] In addition, the technical features involved in the different embodiments of the application described below can be combined with each other as long as there is no conflict between them.

[0030] As Figure 1 shown is a specific embodiment of the flue gas sampling device 100 provided by the present application, at least part of the flue gas sampling device extends into the flue gas to be sampled, for making the flue gas sucked along the front end of the flue gas sampling device to the rear end of the flue gas sampling device, and finally transported to the detection device 200 for temperature and humidity detection, and finally obtaining the moisture content and other parameter information of the flue gas in the flue. Among them, the "front end" mentioned in the present application refers to the end of the sampling device or its component parts away from the detection device 200, and the "rear end" refers to the end of the sampling device or its component parts close to the detection device 200.

[0031] The flue gas sampling device 100 comprises: a front end sampling assembly 10 located at the front end of the sampling device, the front end sampling assembly 10 having a flue gas input port for sucking the flue gas to be detected, the front end sampling assembly 10 comprising: a first inner tube 11, a first outer protective tube 12 and a cap 13; wherein the first outer protective tube 12 is sleeved outside the first inner tube 11 and a first air suction channel 10a is formed between the two, and the inside space of the first inner tube 11 forms a second air suction channel 10b; the cap 13 is fixedly connected to the end of the first inner tube 11 close to the flue gas input port, the outer wall of the cap 13 and the first outer protective tube 12 have a first annular channel 10c, the inner wall of the cap 13 and the first inner tube 11 have a second annular channel 10d, the pipe wall of the first inner tube 11 is provided with a suction hole 11a, and the suction hole 11a is located in the inside area of the cap 13.

[0032] The flue gas sampling device 100 sets the cap 13 at the front end of the first inner tube 11 to block the flue gas from directly entering the first inner tube 11, so that the flue gas enters the sampling device from the first annular channel 10c between the cap 13 and the first outer sleeve 12, and is turned back to the second annular channel 10d and enters the first inner tube 11 through the suction hole 11a. The condensate in the flue gas is directly discharged to the outside along the first suction channel 10a and will not be sucked into the second suction channel 10b inside the first inner tube 11, so that the flue gas in the second suction channel 10b does not contain condensate droplets, so that the sampling result of the sampling device is more accurate.

[0033] Specifically, the suction hole 11a is spaced apart from the rear end of the cap 13, for example, the distance L1 between the suction hole 11a and the rear end of the cap 13 is between 5-10mm, and the length of the cap 13 is 15-25mm in the extension direction of the front end of the first inner tube 11, to further avoid the condensate from being sucked into the first inner tube 11.

[0034] Specifically, the flue gas sampling device 100 further comprises a suction device, the suction device comprising a first suction pump 31 communicating with the first suction channel 10a and a second suction pump 32 communicating with the second suction channel 10b. The suction device is used to accelerate the suction speed of the flue gas, wherein the suction force of the first suction pump 31 is greater than that of the second suction pump 32. The wet flue gas mixed with condensate droplets is sucked into and discharged outside the sampling device by the large flow of the first suction pump 31, and the wet flue gas without condensate droplets is sucked into the rear end for measurement by the small flow of the second suction pump 32 of the first inner tube 11.

[0035] Specifically, in the front-end sampling assembly 10, the first inner tube 11 and the first outer sleeve 12 respectively comprise a first segment and a second segment arranged perpendicular to each other, wherein the flue gas inlet is located on the first segment of the first inner tube 11 and the first outer sleeve 12. When the sampling device is inserted into the flue gas to be detected, the first segment of the first inner tube 11 and the first outer sleeve 12 is consistent with the flue gas flow direction in the flue gas to be detected, and the end thereof is opposite to the flue gas flow direction in the flue gas to be detected, so as to avoid the condensate droplets in the flue gas to be detected entering the flue gas sampling device 100 too much due to the direct flue gas flow direction.

[0036] Specifically, the flue gas sampling device 100 further comprises a rear-end sampling assembly 20 located at the rear end of the sampling device, the rear-end sampling assembly 20 is consistent with the second segment extension direction of the front-end sampling assembly 10, and the rear-end sampling assembly 20 is in communication with the front-end sampling assembly 10 through a connecting assembly 40; the rear-end sampling assembly 20 comprises a second inner tube 21, a second inner protective tube 22 sleeved on the second inner tube 21, and a second outer protective tube 23 sleeved on the outer side of the second inner protective tube 22, wherein the internal space of the second inner tube 21 forms a third suction channel 20a and is in communication with the second suction channel 10b of the first inner tube 11, the rear end of the second inner tube 21 extends into the detection device 200 for detecting the moisture content of the flue gas; the end of the second inner protective tube 22 close to the first inner tube 11 is connected with the second inner tube 21 through the connecting assembly 40, the fourth suction channel 20b is formed between the second inner protective tube 22 and the second outer protective tube 23, and the fourth suction channel 20b is in communication with the first suction channel 10a. Wherein, the third suction channel 20a and the fourth suction channel 20b are isolated from each other, the flue gas of the third suction channel 20a directly enters the detection device 200, and the gas of the fourth suction channel 20b is discharged outside the sampling device through the first suction pump 31.

[0037] Wherein, the second inner tube 21 is provided with a heating device 24 to realize high-temperature heating of the rear segment of the sampling device, and the airflow drawn by the first suction pump 31 passes through the interlayer (i.e. the fourth suction channel 20b) between the second outer protective tube 23 and the second inner protective tube 22, which can effectively block the heat transfer inside the second inner tube 21, so that the temperature of the second outer protective tube 23 is close to the temperature of the flue gas drawn, and the inner environment of the flue is well protected. Specifically, the heating device 24 is an electric heating wire wound on the outer wall of the second inner tube 21, and the heating device 24 is arranged from the starting point to the end point of the outer wall of the second inner tube 21 to realize full-range heating, and the flue gas passing through the second inner tube 21 does not condense when entering the detection device 200.

[0038] Specifically, the connecting assembly 40 comprises an inner connecting sleeve 41, an outer connecting sleeve 42, and a support plate 43; wherein the front end of the inner connecting sleeve 41 is fixedly connected with the first outer protective tube 12 of the front-end sampling assembly 10, and the rear end of the inner connecting sleeve 41 is fixedly connected with the second inner protective tube 22; the outer connecting sleeve 42 is sleeved on the outer side of the inner connecting sleeve 41, the first end of the outer connecting sleeve 42 is fixedly connected with the end of the second inner protective tube 22, and the second end of the outer connecting sleeve 42 is fixedly connected with the end of the second outer protective tube 23; the support plate 43 is fixedly connected with the end of the inner connecting sleeve 41 close to the second inner protective tube 22, and the end of the second inner tube 21 is fixedly connected with the support plate 43.

[0039] More specifically, as Figure 1 , Figure 3As shown, the first outer protective tube 12 is inserted into the front end through hole of the inner connecting sleeve 41 and welded to it. The rear end of the inner connecting sleeve 41 is inserted into the inner side of the second inner protective tube 22. The inner connecting sleeve 41 and the second inner protective tube 22 are sealed together by a sealing ring. The middle part of the support plate 43 is provided with an insertion hole. The front end of the second inner tube 21 is inserted into the insertion hole of the support plate 43. The support plate 43 and the inner connecting sleeve 41 are welded to each other and form a communicating cavity 40b between the first inner tube 11 and the second inner tube 21, so that the rear end of the first inner tube 11 and the front end of the second inner tube 21 are spaced apart, avoiding the problem of excessive airflow noise caused by the difference in pipe diameter when the two are directly connected. The outer side of the support plate 43 is welded to the end of the inner connecting sleeve 41 to prevent the flue gas in the first inner tube 11 from entering the area between the second inner tube 21 and the second inner protective tube 22. Specifically, the inner connecting sleeve 41 is provided with a connecting channel 40a for connecting the first intake channel 10a and the fourth intake channel 20b, and the second inner protective tube 22 is provided with a connecting hole 22a for connecting the first intake channel 10a and the fourth intake channel 20b. The flue gas in the first intake channel 10a enters the fourth intake channel 20b between the second outer protective tube 23 and the second inner protective tube 22 through the rear end of the first outer protective tube 12 along the connecting channel 40a and the connecting hole 22a, and is then drawn to the outside by the first suction pump 31. The aforementioned connecting component 40 can achieve a reliable connection between the front-end sampling component 10 and the rear-end sampling component 20, and after the flow is diverted by the connecting component 40, the flue gas in the inner and outer channels of the rear-end sampling component 20 is sealed and isolated.

[0040] Specifically, the end of the first inner tube 11 furthest from the flue gas inlet (i.e., the rear end of the first inner tube 11) is isolated from the connecting channel 40a of the inner connecting sleeve 41, so that the first suction channel 10a inside the first inner tube 11 is isolated from the flue gas in the connecting channel 40a. More specifically, the middle of the rear end of the inner connecting sleeve 41 is provided with an insertion hole matching the outer diameter of the first inner tube 11, and the distal end of the first inner tube 11 is inserted into the insertion hole and welded to it to achieve isolation of the first suction channel 10a from the flue gas in the connecting channel 40a. Specifically, the second outer protective tube 23 is provided with an outlet port 23a, which is connected to the first suction pump 31.

[0041] like Figure 4 The diagram shows a specific embodiment of the flue gas testing system of the present invention. The testing system includes a flue gas sampling device 100 and a detection device 200 located at the rear end of the flue gas sampling device 100. The detection device 200 includes a temperature sensor 201 and a humidity sensor 202 for detecting the flue gas inside the second inner tube 21.

[0042] Specifically, in the rear end sampling assembly 20 of the flue gas sampling device 100, the rear end of the second outer protective tube 23 is connected with the detection device 200, and the second inner protective tube 22 and the second inner tube 21 extend into the inside of the detection device 200, and the rear end of the second inner tube 21 is in communication with the temperature sensor 201 and the humidity sensor 202 of the detection device 200.

[0043] The flue gas test system of the present application has the following advantages: the flue gas sampling device 100 is arranged to make the flue gas in the first inner tube 11 and the second inner tube 21 consistent with the flue gas in the flue to be detected, so that the detection result is more accurate; the temperature of the outer protective tube of the sampling device is not affected by the high-temperature heating of the inner tube, so that the water vapor content in the flue gas will not be changed due to the sampling device, and the detection accuracy of the test system is further improved.

[0044] Specifically, in one specific embodiment, as shown in Figure 5 The flue gas test system further comprises a temperature measuring element 50 installed on the flue gas sampling device, which is used to detect the temperature of the flue gas entering the front end sampling assembly 10. Since the temperature measuring element 50 is located inside the front section of the gas path and far away from the heating area of the rear section, it is not affected by the heating of the second inner tube 21 located at the rear end, and can more accurately measure the temperature of the flue gas. Specifically, the temperature measuring element 50 comprises a temperature measuring main body 51 and a temperature sensing rod 52. The temperature measuring main body 51 is installed on the support plate 43, and the temperature sensing rod 52 extends into the inside of the first inner tube 11 along the connecting cavity. The end of the temperature sensing rod 52 is close to the first section of the first inner tube 11. More specifically, the support plate 43 is provided with a first mounting hole opposite to the rear end of the first inner tube 11. The temperature measuring main body 51 is installed in the first mounting hole of the support plate 43 through a mounting sleeve 60. A sealing and heat insulation sleeve 70 is arranged on the outside of the temperature measuring main body 51 and the mounting sleeve 60, so as to avoid the temperature measuring element 50 being affected by the heating of the second inner tube 21. The support plate 43 is further provided with a second mounting hole, and the second inner tube 21 is inserted and fixed in the second mounting hole of the support plate 43. The flue gas of the first inner tube 11 enters the inside of the second inner tube 21 through the communication cavity 40b.

[0045] Obviously, the above embodiments are only examples for the purpose of clarity, and are not intended to limit the embodiments. Based on the above description, those skilled in the art can make other different forms of changes or modifications. Here, it is not necessary and impossible to exhaust all the embodiments. The obvious changes or modifications derived therefrom are still within the protection scope of the present application.

Claims

1. A flue gas sampling device, characterized in that, The sampling device comprises: a front-end sampling assembly located at the front end of the sampling device and having a flue gas input port, which comprises a first inner tube, a first outer protective tube, and a cap; wherein the first outer protective tube is sleeved outside the first inner tube and a first air suction passage is formed between the first outer protective tube and the first inner tube, and a second air suction passage is formed in the inner space of the first inner tube; the cap is fixedly connected to the front end of the first inner tube, a first annular passage is formed between the outer wall of the cap and the first outer protective tube, a second annular passage is formed between the inner wall of the cap and the first inner tube, a suction hole is formed in the tube wall of the first inner tube, and the suction hole is located in the inner side region of the cap.

2. The flue gas sampling device of claim 1, wherein, The sampling device further comprises a suction device, which comprises a first suction pump in communication with the first air suction passage and a second suction pump in communication with the second air suction passage.

3. The flue gas sampling device of claim 2, wherein, The suction force of the first suction pump is greater than that of the second suction pump.

4. The smoke sampling device according to any one of claims 1 to 3, characterized in that The sampling device further comprises a rear-end sampling assembly located at the rear end of the sampling device and in communication with the front-end sampling assembly through a connecting assembly; the rear-end sampling assembly comprises: a second inner tube, the inner space of the second inner tube forming a third air suction passage and being in communication with the second air suction passage of the first inner tube; a heating device is arranged on the outer wall of the second inner tube; a second inner protective tube, which is sleeved on the second inner tube and connected to the front end of the second inner tube through a connecting assembly; a second outer protective tube, which is sleeved outside the second inner protective tube and forms a fourth air suction passage between the second inner protective tube and the second outer protective tube, and the fourth air suction passage is in communication with the first air suction passage.

5. The flue gas sampling device of claim 4, wherein, The connecting assembly comprises: an inner connecting sleeve, the front end of the inner connecting sleeve being fixedly connected to the first outer protective tube, and the rear end of the inner connecting sleeve being fixedly connected to the second inner protective tube; a support plate, which is fixedly connected to the rear end of the inner connecting sleeve, and the front end of the second inner tube being arranged through the support plate; an outer connecting sleeve, which is sleeved outside the inner connecting sleeve, the front end of the outer connecting sleeve being fixedly connected to the end of the second inner protective tube, and the rear end of the outer connecting sleeve being fixedly connected to the end of the second outer protective tube.

6. The flue gas sampling device of claim 5, wherein, a connecting passage for connecting the first air suction passage and the fourth air suction passage is arranged on the inner connecting sleeve, and a communication hole for connecting the first air suction passage and the fourth air suction passage is arranged on the second inner protective tube.

7. The flue gas sampling device of claim 6, wherein, the rear end of the first inner tube is isolated from the connecting passage of the inner connecting sleeve.

8. The flue gas sampling device of claim 6, wherein, the rear end of the first inner tube is arranged in a spaced manner with the front end of the second inner tube.

9. The device of claim 4, wherein, an air outlet is arranged on the second outer protective tube, and the air outlet is in communication with the first suction pump.

10. A smoke test system characterized by, The sampling device comprises: the flue gas sampling device according to any one of claims 1-9 and a detection device located at the rear end of the flue gas sampling device.

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