Asphalt flue gas detection system and detection method based on gas internal circulation

Abstract

The invention relates to an asphalt flue gas detection system and method based on gas internal circulation, and the system comprises a flue gas generation system which is used for providing a high-temperature sealed environment for to-be-detected asphalt; the gas testing system is used for detecting flue gas generated by asphalt in the flue gas generating system; the heating control assembly is used for controlling the temperature of the to-be-detected asphalt in the flue gas generation system; the gas testing system comprises a flue gas detection device used for detecting components in flue gas, a gas inlet pipe used for conveying the flue gas generated in the flue gas generation system to the flue gas detection device, and a gas outlet pipe used for conveying the detected gas back to the flue gas generation system. The detection system disclosed by the invention is based on an internal circulation design concept, realizes internal circulation of a pipeline system in the detection system through a multifunctional sealing flange, and solves the problem that the testing process of a current asphalt fume testing device is greatly influenced by external gas.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of asphalt fume detection devices, and relates to an asphalt fume detection system and method based on gas internal circulation. BACKGROUND

[0002] Asphalt pavement construction mainly adopts traditional hot-mixed asphalt mixture technology. During the storage, transportation and construction of petroleum asphalt (including modified asphalt), harmful fumes and irritating odors will be released into the air due to high temperature, which not only pollutes the environment, but also has a negative impact on the health of construction personnel and surrounding residents, especially for rubber asphalt and modified asphalt. The demand for odor removal and smoke suppression of traditional asphalt products is particularly urgent.

[0003] Building a reliable, accurate and convenient asphalt fume evaluation system is the premise of developing petroleum asphalt odor removal and smoke suppression. Asphalt fumes are composed of inorganic components, volatile organic compounds and solid particles. Due to the low content of the measured components, quantitative analysis requires high precision of the measuring equipment, and the test results are easily affected by objective factors such as test and operation methods. Currently, the test of asphalt fume is mainly carried out from indoor test and field test. Field test is easily disturbed by environmental factors, resulting in low reducibility of the collected sample to the field atmosphere. Therefore, indoor test with controllable parameters, stable sample and simple operation based on asphalt fume generation device is still the mainstream of research.

[0004] Many Chinese patents (such as CN 114669168 A, CN 113702311 A, CN 115445345 A, CN 105973742 A, CN 215218222 U, CN 218157728 U, CN 218358715 U, etc.) all use a flask as an asphalt fume generation device, but there are differences in fume detection. However, these devices have the following problems: First, the flask as a generation device has deficiencies in sealing. Second, most devices use traditional stirring devices, and the sealing problem of the stirring device and the flask is an important defect of the device. In addition, these devices all introduce external gas as a flow medium to collect asphalt fume and conduct detection. However, the introduction of external gas inevitably affects the detection results of asphalt fume. SUMMARY

[0005] To solve the above problems, the present application provides an asphalt fume detection system based on gas internal circulation, comprising: a fume generation system for providing a high-temperature sealed environment for the asphalt to be tested; a gas testing system for detecting the fume generated by the asphalt in the fume generation system; A heating control component used to control the temperature of the asphalt to be tested within a flue gas generation system; The gas testing system includes a flue gas detection device for detecting the components in flue gas, an inlet pipe for conveying the flue gas generated in the flue gas generation system to the flue gas detection device, and an outlet pipe for conveying the detected gas back to the flue gas generation system.

[0006] Based on the above scheme, the flue gas generation system includes a reaction vessel, a barrel-shaped heater located outside the reaction vessel, a sealing flange for sealing the reaction vessel, and a stirring system for stirring the asphalt to be tested.

[0007] Based on the above scheme, the sealing flange is provided with an outlet channel for connecting the inside of the reactor, and the outlet channel is connected to the inlet pipe of the flue gas detection device.

[0008] Based on the above scheme, the sealing flange is also provided with an air inlet channel for connecting the reactor, and the air inlet channel is connected to the exhaust pipe of the flue gas detection device.

[0009] Based on the above scheme, the stirring system includes stirring blades and stirring shaft; the stirring shaft is provided with a stirring shaft air inlet channel for connecting the stirring shaft inside the reaction vessel, and the stirring shaft air inlet channel is connected to the air outlet pipe of the flue gas detection device.

[0010] Based on the above scheme, the sealing flange includes an upper flange plate and a lower flange plate; the lower flange plate is provided with a plurality of through holes perpendicular to the lower flange plate for connecting the suction pipe; the lower flange plate has a lower flange outlet channel groove on the surface near the upper flange plate that connects the through holes; the upper flange plate has an upper flange outlet channel groove on the surface near the lower flange plate that cooperates with the lower flange outlet channel groove; the through holes, the lower flange outlet channel groove, and the upper flange outlet channel groove together form an outlet channel.

[0011] Based on the above scheme, the length of the suction tube inserted into several through holes is different, and the length of the channel from the inlet of each suction tube to the outlet of the air outlet channel is the same.

[0012] Based on the above scheme, a liquid circulation assembly for cooling the internal space of the flue gas generation system is also included; the liquid circulation assembly includes a circulation pump, a condenser pipe, an inlet pipe, and an outlet pipe; the condenser pipe is installed inside the flue gas generation system.

[0013] Based on the above scheme, the sealing flange is provided with a water inlet channel for connecting the inlet of the condenser tube and the water inlet pipe, and also with a water outlet channel for connecting the outlet of the condenser tube and the water outlet pipe.

[0014] This application also provides a method for detecting asphalt fumes based on internal gas circulation, wherein the above-mentioned detection system is used during the detection.

[0015] Compared with the prior art, the present invention has the following beneficial effects: The system of this invention employs a reaction vessel and sealing flanges for sealing, effectively solving the sealing problem of current asphalt fume testing devices. The detection system of this invention is based on the "internal circulation" design concept. Through a multi-functional sealing flange, it achieves internal circulation of the piping system within the detection system, solving the problem of significant influence from external gases during the testing process of current asphalt fume testing devices. This invention, through the combined use of split sealing flanges and suction pipes of different lengths, allows the gas to mix along the height of the space, breaking down the hierarchical structure of the gas and ensuring the uniformity of the gas being tested. This invention incorporates a condenser-serpentine water-cooled pipe into the flue gas generator, overcoming the limitation of current asphalt fume testing devices that can only heat but not cool, improving the temperature controllability during the test process, and providing the possibility of continuous temperature-varying testing. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of the detection system in Embodiment 1 of this application; Figure 2 This is a schematic diagram of the flue gas generation system in the detection system of Embodiment 1 of this application; Figure 3 This is a schematic diagram of the sealing flange in a flue gas generation system; Figure 4 This is a schematic diagram of the structure of the lower flange of the sealing flange in the system of this application; Figure 5 This is a schematic diagram of the upper flange of the sealing flange in the system of this application; Figure 6 This is a structural diagram showing the combination of the upper flange plate and the lower flange plate. Figure 7 This is a schematic diagram of the liquid circulation component in the system of this application. Detailed Implementation

[0018] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0019] Example 1 This application provides a specific implementation scheme for an asphalt fume detection system based on internal gas circulation, such as... Figure 1 As shown, the detection system includes: A flue gas generation system 1 is used to provide a high-temperature sealed environment for the asphalt to be tested; Gas testing system 2 is used to detect the flue gas generated by asphalt in flue gas generation system 1; Heating control component 3 for temperature control of the asphalt to be tested in flue gas generation system 1; The gas testing system 2 includes a flue gas detection device 2-1 for detecting the components in the flue gas, an inlet pipe 2-2 for conveying the flue gas generated in the flue gas generating system 1 to the flue gas detection device 2-1, and an outlet pipe 2-3 for conveying the detected gas back to the flue gas generating system 1; a filter membrane clip 2-4 is also provided on the inlet pipe 2-2. The main function of the filter membrane clip 2-4 is to filter solid particles to prevent the flue gas detection device from being contaminated; at the same time, it can collect solid particles to evaluate the proportion of solid particles in the asphalt fumes.

[0020] Most existing detection devices use flasks as the generating unit, which inherently suffers from insufficient sealing. Furthermore, these devices all rely on introducing external gas as the circulation medium to collect and detect asphalt fumes. However, the introduction of external gas inevitably affects the detection results. Therefore, the detection system of this application sets the fume detection device 2-1 and the fume generating system 1 into a single sealed environment, effectively ensuring the system's sealing performance. Simultaneously, the internal circulation environment eliminates the need to introduce external gas.

[0021] The airtightness of the flue gas generating system 1 is crucial for asphalt fume detection. As a specific implementation scheme, this application provides a specific implementation scheme for the flue gas generating system 1, such as... Figure 2As shown, the flue gas generating system 1 includes a reaction vessel 1-1, a barrel-shaped heater 1-2 disposed outside the reaction vessel 1-1, a sealing flange 1-3 for sealing the reaction vessel 1-1, and a stirring system 1-4 for stirring the asphalt to be tested. The barrel-shaped heater 1-2 is controlled by a heating control component 3, which includes a temperature controller 3-1 and a temperature sensor 3-2. The temperature sensor 3-2 penetrates through the sealing flange 1-3 and extends into the interior of the flue gas generating system 1. The technical means of controlling the temperature inside the flue gas generating system 1 through the heating control component 3 is a conventional technical means for those skilled in the art and will not be described in detail here.

[0022] Specifically, the sealing flange 1-3 and the reactor 1-1 are fixed and sealed by bolts (8 bolts are shown in the figure, not labeled). For better sealing, a sealing gasket can be added between the two. The fixing method and sealing method are not innovative in this application, and will not be described in detail here.

[0023] As a specific implementation plan, such as Figure 3 As shown, the sealing flange 1-3 is provided with an outlet channel 1-31 for connecting to the reactor 1-1. The outlet channel 1-31 is connected to the inlet pipe 2-2 of the flue gas detection device 2-1. Thus, during detection, the flue gas generated in the flue gas generating system 1 will enter the flue gas detection device 2-1 through the outlet channel 1-31 and the inlet pipe 2-2.

[0024] The gas detected by the flue gas detection device 2-1 is pumped back into the reaction vessel 1-1. As a specific implementation plan, for example... Figure 3 As shown, the sealing flange 1-3 is also provided with an air inlet channel 1-32 for connecting to the reactor 1-1. The air inlet channel 1-32 is connected to the outlet pipe 2-3 of the flue gas detection device 2-1. The flue gas detection device 2-1 can use the KP830 pump-suction particulate gas detector from Zhong'an Testing.

[0025] Based on the above technical solution, internal gas circulation can be achieved during flue gas detection. For example... Figure 3 As shown, the exhaust channel 1-31 and the inlet channel 1-32 can be directly opened on the sealing flange 1-3, but this method is difficult to implement. Furthermore, the openings of both the exhaust channel 1-31 and the inlet channel 1-32 are located at the top of the reactor 1-1. Gas returned from the inlet channel 1-32 can easily be directly discharged back into the reactor 1-1 through the exhaust channel 1-31, resulting in low detected flue gas concentration and uneven gas mixing. To solve this technical problem, this application also provides another implementation scheme for the inlet channel, such as... Figure 2As shown, the stirring system 1-4 includes a stirring blade 1-41 and a stirring shaft 1-42. The stirring shaft 1-42 is provided with an air inlet channel 1-421 connecting to the reactor 1-1. The air inlet channel 1-421 is connected to the outlet pipe 2-3 of the flue gas detection device 2-1. By placing the air inlet channel on the stirring shaft 1-42, the incoming air can be directly delivered to the lower middle part of the reactor 1-1, allowing for more thorough mixing with the newly generated flue gas. Furthermore, the outlet of the air inlet channel 1-421 is located away from the air inlet channel 1-32, effectively preventing the gas entering the reactor 1-1 from being directly discharged from the reactor 1-1. In addition to the stirring blade 1-41 and the stirring shaft 1-42, the stirring system 1-4 also includes a magnetic stirring speed controller 1-43.

[0026] In the same detection system, air inlet channel 1-32 and air inlet channel 1-421 of the stirring shaft do not need to be set at the same time. It is preferable to use air inlet channel 1-421 of the stirring shaft.

[0027] Based on the above technical solution, in order to reduce the processing difficulty of sealing flange 1-3 and increase the mixing uniformity of asphalt fumes, this application provides a specific implementation scheme for sealing flange 1-3, such as... Figure 4 , Figure 5 and Figure 6 As shown, the sealing flange 1-3 includes an upper flange plate 1-3-1 and a lower flange plate 1-3-2. The lower flange plate 1-3-2 has several through holes 1-311 perpendicular to it for connecting to the suction pipe 1-33. The lower flange plate 1-3-2 has a lower flange outlet channel groove 1-312 on its surface near the upper flange plate 1-3-1, connecting all the through holes 1-311. The upper flange plate 1-3-1 has an upper flange outlet channel groove 1-313 on its surface near the lower flange plate 1-3-2, which cooperates with the lower flange outlet channel groove 1-312. The through holes 1-311, the lower flange outlet channel groove 1-312, and the upper flange outlet channel groove 1-313 together form the outlet channel 1-31. A sealing gasket can be used to seal between the upper flange plate 1-3-1 and the lower flange plate 1-3-2.

[0028] Compared to the integrated sealing flange 1-3, the combined sealing flange 1-3 in this embodiment is much simpler to prepare and install, and it has several through holes 1-311. Figure 4The diagram shows four outlets (one for each type of gas), which allows for the collection of flue gas from multiple points and its eventual discharge from a single outlet. This method results in better mixing of the asphalt fumes, making it more suitable for detection. Furthermore, since asphalt fumes contain a large amount of tar, it adheres to the gas channel during detection. Using integrated sealing flanges 1-3 would make cleaning very difficult, while using separate sealing flanges 1-3 allows for quick and easy cleaning after each use.

[0029] To further improve the mixing uniformity of asphalt fumes, based on the above-mentioned technical solutions, such as... Figure 6 As shown, several suction pipes 1-33 of different lengths are inserted into several through holes 1-311. The suction pipes 1-33 of different lengths can draw in flue gas from different heights in the reactor 1-1, and then mix the drawn flue gas in the channel formed by the upper plate outlet channel groove 1-313 and the lower plate outlet channel groove 1-312. To achieve the best mixing degree, the channel length from the inlet of each suction pipe 1-33 to the outlet of the outlet channel 1-31 is the same, so that the flue gas at different heights in the reactor 1-1 achieves a good degree of mixing when leaving the outlet channel 1-31.

[0030] To prevent gas backflow, a one-way valve (not labeled in the figure) is installed at the connection between the outlet channel 1-31 and the inlet pipe 2-2, and at the connection between the inlet channel 1-32 and the outlet pipe 2-3, to prevent gas from escaping at the interface.

[0031] Preliminary indoor tests revealed that temperature control within the sealed container is one of the challenges encountered by asphalt fume detection devices. Temperature sensor 3-2 collects the temperature signal from the inside of the asphalt, while the temperature of the external reaction container is typically much higher than the internal material temperature. The sealed condition reduces energy exchange between the reaction container and the external environment, leading to a "temperature surge" problem in the internal material during the test. However, the release behavior of asphalt fumes is significantly affected by the test temperature. Therefore, solving the temperature control problem of the asphalt fume detection device is also a key factor in ensuring data reliability and reproducibility. To address this, based on the aforementioned technical solutions, such as... Figure 1 As shown, the detection system also includes a liquid circulation component 4 for cooling the internal space of the flue gas generating system 1; as Figure 7 As shown, the liquid circulation component 4 includes a circulation pump 4-1, a condenser pipe 4-2, a water inlet pipe 4-3, and a water outlet pipe 4-4; the condenser pipe 4-2 is installed inside the flue gas generation system 1.

[0032] like Figure 3As shown, the sealing flange 1-3 is provided with a water inlet channel 1-34 for connecting the inlet of the condenser pipe 4-2 and the water inlet pipe 4-3, and also with a water outlet channel 1-35 for connecting the outlet of the condenser pipe 4-2 and the water outlet pipe 4-4. Specifically, the condenser pipe 4-2 is a serpentine water-cooled pipe.

[0033] like Figure 4 and Figure 5 As shown, the water inlet channel 1-34 and the water outlet channel 1-35 are also opened on the upper flange plate 1-3-1 and the lower flange plate 1-3-2. For details, please refer to the opening of the gas channel, which will not be elaborated here.

[0034] Example 2 Based on the detection system in Example 1, this application provides a method for detecting asphalt fumes based on internal gas circulation. Specifically, the detection method includes the following steps: S1. Place the asphalt to be tested into the oven for heating, and turn on the heating control component 3 to heat the reaction vessel 1-1 of the flue gas generation system 1 to the test temperature; S2. After the asphalt sample is heated to a fluid state, weigh the asphalt sample to be tested and immediately transfer it into the reaction vessel 1-1. Then, quickly fix the sealing flange 1-3 to the reaction vessel 1-1. Generally, weigh 150g ± 5g of the asphalt sample to be tested. S3. According to the test set temperature and the actual test temperature, adjust the heating control component 3 and the liquid circulation component 4, and turn on the stirring system 1-4, control the stirring speed to 100 rpm, and maintain the temperature for 5 minutes after it reaches the test temperature ±0.5℃. S4. Turn on the gas testing system 2 and set the data acquisition interval to 1 minute and the detection duration to 1 hour; S5. After the test is completed, shut down the system and organize and analyze the obtained data.

[0035] If the temperature deviates from the set value by ±3℃ during the test, the test result is considered invalid and the test needs to be repeated; three parallel samples are selected for measurement in each test group.

[0036] The various embodiments in this specification are described in a related manner. Similar or identical parts between embodiments can be referred to interchangeably. Each embodiment focuses on its differences from other embodiments. The above descriptions are merely preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention are included within the scope of protection of the present invention.

Claims

1. A gas recirculation based asphalt fume detection system, characterized by, The utility model relates to a kind of asphalt smoke detection systems based on gas internal circulation, including: Flue gas generation system (1) for providing high temperature sealing environment for asphalt to be measured; Gas testing system (2) for detecting flue gas generated by asphalt in flue gas generation system (1); Heating control assembly (3) for temperature control to asphalt to be measured in flue gas generation system (1); The gas testing system (2) includes flue gas detection device (2-1) for detecting components in flue gas, gas inlet pipe (2-2) for conveying flue gas generated in flue gas generation system (1) to flue gas detection device (2-1) and gas outlet pipe (2-3) for conveying detected gas back to flue gas generation system (1).

2. The asphalt smoke detection system based on gas internal circulation according to claim 1, wherein The flue gas generation system (1) includes a reaction kettle (1-1), a barrel-type heater (1-2) disposed outside the reaction kettle (1-1), a sealing flange (1-3) for sealing the reaction kettle (1-1), and a stirring system (1-4) for stirring the asphalt to be measured.

3. The gas recirculation based asphalt fume detection system of claim 2, wherein, The sealing flange (1-3) is provided with an exhaust passage (1-31) for communicating with the reaction kettle (1-1), and the exhaust passage (1-31) is communicated with the gas inlet pipe (2-2) of the flue gas detection device (2-1).

4. The gas recirculation based asphalt fume detection system of claim 3, wherein, The sealing flange (1-3) is also provided with an air inlet passage (1-32) for communicating with the reaction kettle (1-1), and the air inlet passage (1-32) is communicated with the gas outlet pipe (2-3) of the flue gas detection device (2-1).

5. The gas recirculation based asphalt fume detection system of claim 3, wherein, The stirring system (1-4) includes stirring paddles (1-41) and a stirring shaft (1-42), and the stirring shaft (1-42) is provided with a stirring shaft air inlet passage (1-421) for communicating with the reaction kettle (1-1), and the stirring shaft air inlet passage (1-421) is communicated with the gas outlet pipe (2-3) of the flue gas detection device (2-1).

6. The gas recirculation based asphalt fume detection system of claim 3, wherein, The sealing flange (1-3) includes a flange upper disc (1-3-1) and a flange lower disc (1-3-2), the flange lower disc (1-3-2) is provided with a plurality of through holes (1-311) perpendicular to the flange lower disc (1-3-2) for connecting the air suction pipe (1-33), the flange lower disc (1-3-2) is provided with a lower disc exhaust passage groove (1-312) on the surface close to the flange upper disc (1-3-1) side for communicating with each through hole (1-311), the flange upper disc (1-3-1) is provided with an upper disc exhaust passage groove (1-313) on the surface close to the flange lower disc (1-3-2) side for cooperating with the lower disc exhaust passage groove (1-312), and the through hole (1-311), the lower disc exhaust passage groove (1-312) and the upper disc exhaust passage groove (1-313) together constitute the exhaust passage (1-31).

7. The gas recirculation based asphalt fume detection system of claim 6, wherein, The air suction pipes (1-33) inserted into the plurality of through holes (1-311) have different lengths, and the channel length between the inlet of each air suction pipe (1-33) and the outlet of the exhaust passage (1-31) is the same.

8. The gas recirculation based asphalt fume detection system of claim 1, wherein, Also included is a liquid circulation assembly (4) for cooling the internal space of the smoke generation system (1); the liquid circulation assembly (4) comprises a circulation pump (4-1), a condensing pipe (4-2), a water inlet pipe (4-3) and a water outlet pipe (4-4); the condensing pipe (4-2) is arranged in the smoke generation system (1).

9. The gas recirculation based asphalt fume detection system of claim 8, wherein, An inlet water passage (1-34) for connecting the inlet of the condensing pipe (4-2) and the water inlet pipe (4-3) is arranged on the sealing flange (1-3), and an outlet water passage (1-35) for connecting the outlet of the condensing pipe (4-2) and the water outlet pipe (4-4) is also arranged.

10. A method for detecting asphalt fume based on gas internal circulation, characterized in that, The detection system of any one of claims 1-9.

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