Device for simulating emission of volatile pollutants in service stage of asphalt pavement and test method thereof

Abstract

The invention discloses a device for simulating emission of volatile pollutants in a service stage of an asphalt pavement and a test method of the device. The device comprises a heat preservation box, a device table, an aging bottle and a gas collection system, the middle part of the incubator is separated by a heat-insulating baffle, and ultraviolet lamps are respectively arranged at the top of the incubator; an aging bottle support is arranged on the upper portion of the device table, a heating pad is arranged in the aging bottle support, and a heating adjusting system is located in the device table. External threads are arranged at the opening of the aging bottle, internal threads are arranged in the bottle cap, the internal threads and the external threads are matched with each other and are provided with a sealing gasket, two vent holes are formed in the opening of the bottle cap, two conduits with different lengths penetrate through the vent holes, the thermometer penetrates through the bottle cap and extends into the bottle body, and sealing gaskets are arranged among the conduits, the thermometer and the bottle cap; the gas collection system comprises a gas pump, a valve and a gas collection bag. The device can simulate volatile pollution discharged in the use stage of pavement asphalt, collect and analyze the release condition of pollution gas, and provide powerful support for road environmental protection research and practical application.

Description

Technical Field

[0001] The present invention relates to the technical field of asphalt material research, and in particular to a device for simulating the emission of volatile pollutants during the service stage of an asphalt pavement and a test method thereof, which are used for analyzing the volatile pollutants emitted by the pavement asphalt during the use stage. Background Art

[0002] Asphalt materials are widely used in highway pavement projects. Studies have shown that pollutants released during the use of asphalt pavement are a major non-traditional source of secondary organic aerosol (SOA) precursors. It is estimated that in cities, the annual emission of asphalt-related SOA precursors has exceeded the estimated value of motor vehicles. In addition, due to global warming, summer temperatures around the world are on a straight upward trend, and studies have found that asphalt material emissions will be concentrated in the hottest and sunniest summer, causing the release of a large amount of SOA precursors, polluting the environment. In addition, SOA is a major source of PM2.5 and will also have adverse effects on human health.

[0003] At present, the research on the impact of environmental conditions on asphalt emissions, especially solar radiation conditions, mainly focuses on the performance, life and greenhouse gases of asphalt. Due to the long emission time scale of asphalt in the use stage, the source profile is easily confused with vehicle emissions in environmental conditions. There is currently insufficient research on the emission pathways of asphalt, and the changes in variables such as solar radiation, temperature and humidity during the use process are consistent throughout. Few studies have analyzed and studied the pollutant emissions during the use stage of asphalt. The relevant test devices based on indoor tests mainly include thin film ovens, rotary thin film ovens and pressure aging instruments, which are used to simulate the aging of asphalt under hot oxygen conditions and analyze the performance and service life of asphalt materials. There is no corresponding test device and related test method that can simulate and analyze the volatile emissions related to asphalt under the conditions of the use stage. Summary of the invention

[0004] The purpose of the present invention is to provide a device for simulating the emission of volatile pollutants during the service stage of asphalt pavement and a test method thereof. The device can simulate the use of asphalt under natural environmental conditions, including providing solar radiation, rainfall and temperature rise conditions. After the simulation experiment, the volatile pollutants emitted by the asphalt can be efficiently collected through an air pump and an air collection bag, which is convenient for subsequent analysis.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions to achieve it.

[0006] (1) A device for simulating the emission of volatile pollutants during the service stage of an asphalt pavement, comprising an insulated box, an apparatus table, an aging bottle and an air collection system; the middle of the insulated box is separated by a temperature-insulating baffle, and ultraviolet lamps are arranged on the top of each insulated box; an aging bottle holder is arranged on the top of the apparatus table, and a heating pad is built in the aging bottle holder, and a heating adjustment system of the heating pad is located inside the apparatus table; an external thread is arranged at the mouth of the aging bottle, and an internal thread is arranged inside the bottle cap, the internal thread and the external thread cooperate with each other and a sealing gasket is arranged, the upper opening of the bottle cap is designed with two ventilation holes, two catheters of different lengths pass through the ventilation holes, a thermometer passes through the bottle cap and extends into the aging bottle, and a sealing gasket is arranged between the catheter, the thermometer and the bottle cap; the air collection system comprises an air pump, a valve and an air collection bag.

[0007] According to the device for simulating the emission of volatile pollutants during the service stage of asphalt pavement of the present invention, the insulation box is made of heat-insulating material, the outer dimensions of the box are length×width×height=450mm×450mm×700mm, and the inner dimensions are length×width×height=400mm×400mm×600mm; two identical device tables are designed on the left and right sides of the box body, with a total height of 200mm, a length and width of 150mm, and a thickness of 50mm on the device table surface, which is convenient for embedding the heating pad adjustment system; the aging bottle is made of glass, the total height of the bottle body is 200mm, the wall thickness is 1mm, the radius is 50mm, the height of the bottle cap is 30mm±1.5mm, the radius of the thermometer hole is 4mm, and the radius of the two ventilation holes is 6mm, and in order to ensure the sealing of the aging bottle, a sealing ring is provided at the joint between the bottle body and the bottle cap, and anti-slip grooves are provided on the outside of the bottle cap, in order to facilitate the unscrewing of the bottle cap after the test.

[0008] Preferably, the thermal insulation box is equipped with two independent left and right doors, and an ultraviolet light switch is arranged on the upper part of the door.

[0009] Preferably, the device table is placed inside the incubator.

[0010] Preferably, the body size of the aging bottle is slightly smaller than the aging bottle bracket, and the aging bottle is connected to the aging bottle bracket via a steel frame.

[0011] According to the device for simulating volatile pollutant emission during the service stage of an asphalt pavement of the present invention, the steel frame is in the shape of a truncated cone with a small top and a large bottom, the upper part of which firmly holds the aging bottle, and the lower part of which is connected to the aging bottle bracket.

[0012] Preferably, the aging bottle holder is cylindrical, the aging bottle holder is equipped with a middle interlayer, and a heating pad is arranged on the upper part of the middle interlayer.

[0013] According to the device for simulating the emission of volatile pollutants during the service stage of an asphalt pavement of the present invention, the aging bottle bracket is a thin-walled cylinder with a height of 150 mm, a radius of 55 mm, and a thickness of 1 mm. The thickness of the middle interlayer is 30 mm. The lower part of the steel frame is connected to the middle interlayer of the aging bottle bracket. The vertical rotation of the middle interlayer can drive the entire aging bottle to rotate.

[0014] Preferably, a cylindrical steel pipe is embedded in the middle interlayer, the steel pipe is in a shape with large ends and a small middle, and the steel pipe is connected to the aging bottle bracket through two external slide rails.

[0015] According to the device for simulating the emission of volatile pollutants during the service stage of an asphalt pavement of the present invention, the steel pipe is 60 mm in length and 30 mm in diameter, and is tightly connected to the middle interlayer. Both ends of the steel pipe can move on the slide rails, so as to facilitate the control of the aging bottle bracket to drive the aging bottle to rotate vertically, and the rotation angle range is -30° to 30°.

[0016] Preferably, the sample is separated from water by a filter support inside the aging bottle.

[0017] According to the device for simulating the emission of volatile pollutants during the service stage of an asphalt pavement of the present invention, the filter bracket has a height of 30 mm and a radius of 55 mm, and is tightly fitted with the aging bottle and placed at the bottom of the aging bottle.

[0018] (II) A test method for simulating the emission of volatile pollutants during the service period of an asphalt pavement, based on the above-mentioned device for simulating the emission of volatile pollutants during the service period of an asphalt pavement, comprising the following experimental steps:

[0019] Step 1, check the sealing performance of the test device. The air tightness can be checked by the air extraction method: plug the vent hole 1 with a wooden plug, insert the catheter into the vent hole 2 first, connect the syringe to the catheter port with a hose, pull the syringe piston outward for a distance and then release it. If the syringe returns to its original position, it means that the device is airtight.

[0020] Step 2, taking about 500g of asphalt with different properties according to the experimental plan;

[0021] Step 3: first pour distilled water into the bottle until the liquid level is slightly lower than the filter bracket, then pour asphalt into the bottle above the filter bracket, and close the bottle cap and vent hole;

[0022] Step 4, using an ultraviolet lamp with UVA wavelength intensity, simulating sunlight exposure by controlling the switch of the ultraviolet lamp; heating the asphalt by controlling the heating pad, the heating temperature range is 50℃~80℃, the heating rate range is 1℃ / min~3℃ / min, observing the temperature of the asphalt by a thermometer, simulating the heating condition; controlling the steel pipe in the middle of the aging bottle bracket to vertically rotate the aging bottle bracket, so that the asphalt contacts with water, simulating rainfall;

[0023] Step 5, after the reaction is completed, open the vent, insert the catheter, connect the two catheters to the air pump and the gas collection bag respectively, open the gas valve, and collect the gas;

[0024] Step 6: Use gas analysis equipment to analyze the gas in the gas collection bag. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0026] Figure 1 is a schematic diagram of a device for simulating the emission of volatile pollutants during the service stage of an asphalt pavement according to the present invention, Figure 1 Contains detailed description of the internal structure of the device. Figure 2 It is an overall schematic diagram.

[0027] Among them, 1 is an insulated box; 101 is a baffle; 102 is a box door; 103 is an ultraviolet lamp; 104 is an ultraviolet lamp switch; 2 is a device table; 201 is a heating pad adjustment system; 3 is an aging bottle bracket; 301 is a steel frame; 302 is a middle interlayer; 303 is a slide rail; 304 is a steel pipe; 305 is a heating pad; 4 is an aging bottle; 401 is a bottle cap; 402 is a vent; 403 is a catheter; 404 is a thermometer; 405 is a sealing gasket; 406 is a filter bracket; 5 is a gas collection system; 501 is an air pump; 502 is a valve; 503 is a gas collection bag. DETAILED DESCRIPTION

[0028] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary persons in the art without creative work are within the scope of protection of the present invention.

[0029] For ease of description, spatially relative terms may be used herein to describe the relationship of one element or feature relative to another element or feature as shown in the figures, such as "inside", "outside", "upper", "lower", etc. These spatially relative terms are intended to describe different orientations of the device during use or operation, including orientations other than those depicted in the figures.

[0030] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "install", "connect" and "connected" should be understood in a broad sense. For ordinary personnel in this field, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances.

[0031] refer to Figure 1The device for simulating the emission of volatile pollutants during the service stage of an asphalt pavement according to the content of the present invention comprises an insulated box 1, a device table 2, an aging bottle 4 and a gas collection system 5; the middle part of the insulated box 1 is separated by a heat-insulating baffle 101, and the top of the insulated box 1 is provided with an ultraviolet lamp 103; an aging bottle holder 3 is provided on the upper part of the device table 2, and a heating pad 305 is built in the aging bottle holder 3, and a heating adjustment system 201 of the heating pad 305 is located inside the device table 2; the mouth of the aging bottle 4 is provided with External thread, the inside of the bottle cap 401 is provided with an internal thread, the internal thread and the external thread cooperate with each other and are provided with a sealing gasket, the opening of the bottle cap 401 is designed with two ventilation holes 402, two catheters 403 of different lengths pass through the ventilation holes 402, a thermometer 404 passes through the bottle cap 401 and extends into the aging bottle 4, a sealing gasket 405 is provided between the catheter 403, the thermometer 404 and the bottle cap 401; the gas collection system 5 includes an air pump 501, a valve 502 and an air collection bag 503.

[0032] In the above embodiment, the insulated box 1 is made of heat-insulating material, the outer dimensions of the box are length × width × height = 450mm × 450mm × 700mm, and the inner dimensions are length × width × height = 400mm × 400mm × 600mm; two identical device tables 2 are designed on the left and right sides of the box body, with a total height of 200mm, a length and width of 150mm, and a thickness of 50mm on the surface of the device table 2, which is convenient for embedding the heating pad adjustment system 201; the aging bottle 4 is made of glass, the total height of the bottle body is 200mm, the wall thickness is 1mm, its radius is 50mm, the height of the bottle cap 401 is 30mm±1.5mm, the radius of the thermometer hole is 4mm, and the radius of the two vents 402 is 6mm, and in order to ensure the sealing of the aging bottle, a sealing ring is set at the joint of the bottle body and the bottle cap 401, and an anti-slip pattern is set on the outside of the bottle cap 401 to facilitate unscrewing the bottle cap after the test.

[0033] refer to Figure 1 According to one embodiment of the present invention, the thermal insulation box 1 is equipped with two independent left and right doors 102 , and an ultraviolet light switch 104 is arranged on the upper part of the door 102 .

[0034] refer to Figure 1 According to one embodiment of the present invention, the device table 2 is placed inside the incubator 1 .

[0035] refer to Figure 1 According to one embodiment of the present invention, the body size of the aging bottle 4 is slightly smaller than the aging bottle bracket 3 , and the aging bottle 4 is connected to the aging bottle bracket 3 via a steel frame 301 .

[0036] In the above embodiment, the steel frame 301 is in the shape of a truncated cone with a small top and a large bottom. The upper part firmly holds the aging bottle 4 and the lower part is connected to the aging bottle bracket 3.

[0037] refer to Figure 1 According to one embodiment of the present invention, the aging bottle holder 3 is cylindrical, and the aging bottle holder 3 is provided with a middle interlayer 302 , and a heating pad 305 is arranged on the upper part of the middle interlayer 302 .

[0038] In the above embodiment, the aging bottle holder 3 is a thin-walled cylinder with a height of 150 mm, a radius of 55 mm, and a thickness of 1 mm. The thickness of the middle interlayer 302 is 30 mm. The lower part of the steel frame 301 is connected to the middle interlayer 302 of the aging bottle holder. The vertical rotation of the middle interlayer 302 can drive the entire aging bottle to rotate.

[0039] refer to Figure 1 According to one embodiment of the present invention, a cylindrical steel pipe 304 is embedded in the middle interlayer 302 . The steel pipe 304 is large at both ends and small in the middle. The steel pipe 304 is connected to the aging bottle holder 3 through two external slide rails 303 .

[0040] In the above embodiment, the steel pipe 304 is 60 mm long and 30 mm in diameter, and is tightly connected to the middle interlayer 302. Both ends of the steel pipe 304 can move on the slide rail 303, which is convenient for controlling the vertical rotation angle of the aging bottle bracket 3 to drive the aging bottle 4, and the rotation angle range is -30° to 30°.

[0041] refer to Figure 1 According to one embodiment of the present invention, the filter support 406 is used to separate the sample from the water inside the aging bottle 4 .

[0042] In the above embodiment, the filter support 406 has a height of 30 mm and a radius of 55 mm, and is tightly fitted with the aging bottle 4 and placed at the bottom of the aging bottle 4 .

[0043] A test method for simulating the emission of volatile pollutants during the service stage of an asphalt pavement, based on the above-mentioned device for simulating the emission of volatile pollutants during the service stage of an asphalt pavement, comprises the following experimental steps:

[0044] Step 1, check the sealing performance of the test device. The air tightness can be checked by the air extraction method: plug the vent hole 1 with a wooden plug, insert the catheter into the vent hole 2 first, connect the syringe to the catheter port with a hose, pull the syringe piston outward for a distance and then release it. If the syringe returns to its original position, it means that the device is airtight.

[0045] Step 2, taking about 500g of asphalt with different properties according to the experimental plan;

[0046] Step 3: first pour distilled water into the bottle until the liquid level is slightly lower than the filter bracket, then pour asphalt into the bottle above the filter bracket, and close the bottle cap and vent hole;

[0047] Step 4, using an ultraviolet lamp with UVA wavelength intensity, simulating sunlight exposure by controlling the switch of the ultraviolet lamp; heating the asphalt by controlling the heating pad, the heating temperature range is 50℃~80℃, the heating rate range is 1℃ / min~3℃ / min, observing the temperature of the asphalt by a thermometer, simulating the heating condition; controlling the steel pipe in the middle of the aging bottle bracket to vertically rotate the aging bottle bracket, so that the asphalt contacts with water, simulating rainfall;

[0048] Step 5: After the reaction is completed, open the vent hole, insert the catheter, and connect the two catheters to the air pump and the air collection bag respectively. Open the gas valve and collect the gas;

[0049] Step 6: Use gas analysis equipment to analyze the gas in the gas collection bag.

[0050] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, it should be understood by those skilled in the art that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features therein may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A device for simulating the emission of volatile pollutants during the service period of an asphalt pavement, characterized in that: It comprises an insulated box (1), a device table (2), an aging bottle (4) and a gas collection system (5); The middle part of the heat preservation box (1) is separated by a heat insulation baffle (101), and the top of each heat preservation box (1) is provided with an ultraviolet lamp (103); An aging bottle support (3) is provided on the upper part of the device platform (2), and a built-in heating pad (305), and a heating adjustment system (201) thereof is located inside the device platform (2); The mouth of the aging bottle (4) is provided with an external thread, and the inside of the bottle cap (401) is provided with an internal thread, the internal and external threads cooperate with each other and are provided with a sealing gasket, the upper opening of the bottle cap (401) is designed with two vents (402), two conduits (403) of different lengths pass through them, a thermometer (404) passes through the bottle cap (401) and extends into the bottle body, and a sealing gasket (405) is provided between the conduit (403), the thermometer (404) and the bottle cap (401); The gas collection system (5) comprises an air pump (501), a valve (502) and a gas collection bag (503).

2. The device for simulating the emission of volatile pollutants during the service period of an asphalt pavement according to claim 1 is characterized in that: The heat preservation box (1) is equipped with two independent box doors (102) on the left and right, and an ultraviolet light switch (104) is arranged on the upper part of the box door (102).

3. The device for simulating the emission of volatile pollutants during the service period of asphalt pavement according to claim 1 is characterized in that: The device table (2) is placed inside the thermal insulation box (1).

4. The device for simulating the emission of volatile pollutants during the service period of an asphalt pavement according to claim 1, characterized in that: The body size of the aging bottle (4) is slightly smaller than that of the aging bottle support (3), and the aging bottle (4) and the aging bottle support (3) are connected via a steel frame (301).

5. The device for simulating the emission of volatile pollutants during the service period of an asphalt pavement according to claim 4, characterized in that: The aging bottle support (3) is cylindrical, and is provided with a middle interlayer (302), and a heating pad (305) is arranged on the upper part of the middle interlayer (302).

6. The device for simulating the emission of volatile pollutants during the service period of an asphalt pavement according to claim 5, characterized in that: A cylindrical steel pipe (304) is embedded inside the middle interlayer (302), and the steel pipe (304) is in a shape of large ends and small middle part. The steel pipe (204) is connected to the aging bottle support (3) through two external slide rails (303).

7. The device for simulating the emission of volatile pollutants during the service period of asphalt pavement according to claim 1, characterized in that: The sample is separated from water inside the aging bottle (4) through a filter support (406).

8. A test method for simulating the emission of volatile pollutants during the service period of asphalt pavement, characterized in that: The device for simulating the emission of volatile pollutants during the service stage of an asphalt pavement according to any one of claims 1 to 7 comprises the following test steps: Step 1, check the sealing performance of the test device. The air tightness can be checked by the air extraction method: plug the vent hole 1 with a wooden plug, insert the catheter into the vent hole 2 first, connect the syringe to the catheter port with a hose, pull the syringe piston outward for a distance and then release it. If the syringe returns to its original position, it means that the device is airtight. Step 2, taking about 500g of asphalt with different properties according to the experimental plan; Step 3: first pour distilled water into the bottle until the liquid level is slightly lower than the filter bracket, then pour asphalt into the bottle above the filter bracket, and close the bottle cap and vent; Step 4, using an ultraviolet lamp with UVA wavelength intensity, simulating sunlight exposure by controlling the switch of the ultraviolet lamp; heating the asphalt by controlling the heating pad, the heating temperature range is 50℃~80℃, the heating rate range is 1℃ / min~3℃ / min, observing the temperature of the asphalt by a thermometer, simulating the heating condition; controlling the steel pipe in the middle of the aging bottle bracket to vertically rotate the aging bottle bracket, so that the asphalt contacts with water, simulating rainfall; Step 5, after the reaction is completed, open the vent, insert the catheter, connect the two catheters to the air pump and the gas collection bag respectively, open the gas valve, and collect the gas; Step 6: Use gas analysis equipment to analyze the gas in the gas collection bag.

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