Air mixing and diluting device for high-concentration waste gas

Abstract

The utility model discloses a high-concentration waste gas mixed air diluting device, which belongs to the technical field of environmental protection and energy conservation and comprises a diluting air conveying pipeline structure, the diluting air conveying pipeline structure is connected with one end of a diluting structure, and the other end of the diluting structure is connected with a mixed air output pipeline. The other end of the mixed air output pipeline is connected with one end of a mixed air conveying structure through a first pipeline, and the other end of the mixed air conveying structure is connected with waste gas treatment equipment. According to the utility model, mixed air is uniformly diluted, and the safety is guaranteed in the mixing process.

Description

Technical Field

[0001] The utility model belongs to the technical field of environmental protection and energy saving, and in particular relates to a high-concentration exhaust gas mixing and dilution device. Background Art

[0002] In industries such as coal mining and printing, a lot of high-concentration flammable and explosive waste gases are generated. Direct discharge of these waste gases will cause environmental pollution and energy waste. Since high-concentration flammable and explosive waste gases are mixed with air during the collection process, there are greater risks in transmission and treatment. Therefore, it is not suitable to directly pass them into waste gas treatment equipment (such as RTO, direct-fired furnace, etc.) for treatment. They must be diluted in advance to reach a safe concentration that the treatment equipment can accept before they can be safely treated. The key to high-concentration waste gas treatment in the prior art lies in the uneven dilution of mixed air and the weak safety of the mixing process.

[0003] For example, the patent text "Gas Mixing System" (application number 201720882278.5, publication number CN207064010U, publication date March 2, 2018) proposes a gas mixing system. After fluid finite element analysis, the mixing effect of its mixing device is not good. After mixing, the high-concentration exhaust gas is basically concentrated in the center of the pipe section. The methane concentration decreases step by step from the center to the pipe wall. At a distance of 5m from the mixing device, the highest concentration range is more than 22% of the exhaust gas inlet concentration. There is no safety discharge device, and there are certain safety risks. Utility Model Content

[0004] The utility model aims to provide a high-concentration exhaust gas mixed air dilution device, which realizes uniform dilution of the mixed air and ensures safety during the mixing process.

[0005] The technical solution adopted by the utility model is that the high-concentration exhaust gas mixed air dilution device comprises a dilution structure, one end of the dilution structure is connected to a dilution air fan for conveying dilution air, and the other end of the dilution structure is sequentially connected to a mixed air output pipeline, a first pipeline, and a mixed air transport structure;

[0006] The dilution structure includes a mixed air duct and a barrier box connected in sequence, the barrier box is connected to the mixed air output duct, and the mixed air duct is connected to a high-concentration exhaust gas transportation structure;

[0007] A dispersion screen cylinder and a swirl blade device are sequentially arranged in the air mixing duct along the air outlet direction of the dilution air fan;

[0008] The mixed air output duct is provided with a mixed air duct explosion relief piece;

[0009] The first pipeline is connected with a LEL concentration detection device.

[0010] The utility model is also characterized in that:

[0011] The air outlet of the dilution air fan is connected to the mixing air duct through a dilution air duct, and a first pressure transmitter and a dilution air duct pneumatic butterfly valve are sequentially arranged on the outside of the dilution air duct along the air outlet direction of the dilution air fan.

[0012] The dispersion screen drum is in an inverted T-shape, and a plurality of diversion holes are opened on the horizontal tube wall of the dispersion screen drum. One end of the horizontal pipe of the dispersion screen drum is connected to the dilution air pipe, and the other end of the horizontal pipe of the dispersion screen drum is in a blocked state. The swirl blade device includes an intermediate fixed cylinder, and a plurality of swirl blades are fixedly connected to the intermediate fixed cylinder. The plurality of swirl blades are evenly distributed along the circumference of the intermediate fixed cylinder. The ends of the plurality of swirl blades away from the intermediate fixed cylinder are fixedly connected to the outer ring of blades, and the outer ring of blades is fixedly connected to the mixed air pipe.

[0013] A blocking device is fixedly connected to the central axis position in the blocking box, and the blocking device comprises channel steels fixedly connected to the inner wall of the blocking box in a horizontal and vertical cross manner and a blocking plate fixedly connected to one side of the channel steel close to the air mixing duct.

[0014] The high-concentration exhaust gas transportation structure includes a high-concentration exhaust gas pipeline, one end of the high-concentration exhaust gas pipeline is connected to a high-concentration exhaust gas pipeline pneumatic butterfly valve, the other end of the high-concentration exhaust gas pipeline pneumatic butterfly valve is connected to a high-concentration exhaust gas pipeline pneumatic regulating valve through a third pipeline, and the other end of the high-concentration exhaust gas pipeline pneumatic regulating valve is connected to the vertical pipeline of the dispersion screen cylinder through a pipeline.

[0015] The outside of the third pipeline is connected with a second pressure transmitter, and the third pipeline is also provided with a high-concentration exhaust gas pipeline explosion relief piece.

[0016] The high-concentration exhaust gas pipeline is provided with a high-concentration exhaust gas pipeline emptying lift valve.

[0017] The mixed air transport structure comprises a mixed air duct, a second pipeline and a mixed air duct manual butterfly valve which are connected in sequence, and the mixed air duct is communicated with the first pipeline.

[0018] The second pipeline is connected with a mixing air duct exhaust lift valve.

[0019] The beneficial effects of the utility model are:

[0020] (1) The high-concentration exhaust gas mixing and dilution device of the utility model improves the uniformity of the mixed air. Through the fluid finite element analysis, the highest concentration of exhaust gas in the pipeline 5m away from the dilution structure outlet is reduced to less than 13%.

[0021] (2) The improved air mixing efficiency of the high-concentration exhaust gas air mixing and dilution device of the utility model reduces the length of the subsequent mixing pipe section.

[0022] (3) The utility model high-concentration exhaust gas mixing and dilution device adds an explosion relief device to the high-concentration exhaust gas pipeline and adds an explosion relief device to the dilution structure outlet pipeline, thereby improving the safety of the mixed air and reducing the economic losses caused by the explosion.

[0023] (4) The high-concentration exhaust gas mixing and dilution device of the utility model adds a pressure regulating system on the high-concentration exhaust gas pipeline, which can effectively ensure that the air volume and air pressure delivered will not exceed the design maximum value of the dilution structure.

[0024] (5) The high-concentration exhaust gas mixed air dilution device of the utility model adds a zero-leakage vent lift valve to the high-concentration exhaust gas pipeline and the mixed gas pipeline, thereby ensuring that there will be no exhaust gas leakage during normal operation of the system, and also ensuring the exhaust gas is vented in an emergency.

[0025] (6) The utility model high-concentration exhaust gas mixed air dilution device is equipped with an LEL concentration detection device on the mixed air duct, and different detection equipment can be selected according to different exhaust gas components, which can enhance the applicability of the device.

[0026] (7) The utility model high-concentration exhaust gas mixed air dilution device is equipped with a manual regulating valve on the mixed air duct, which can adjust the air pressure sent to the exhaust gas treatment equipment to ensure the smooth operation of the exhaust gas treatment equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 This is a schematic diagram of the structure of the high-concentration exhaust gas mixing and dilution device of the utility model;

[0028] Figure 2 It is a structural schematic diagram of the dilution structure in the utility model;

[0029] Figure 3 It is a structural schematic diagram of the swirl blade device in the utility model;

[0030] Figure 4 It is a schematic diagram of the structure of the barrier device in the utility model;

[0031] Figure 5 It is a schematic diagram of the internal structure of the high-concentration exhaust gas transport structure in the utility model;

[0032] Figure 6 This is a finite element analysis diagram of the fluid of the dilution structure mixing air effect in the utility model.

[0033] In the figure, 1. Dilution air fan, 2. Dilution air duct pneumatic butterfly valve, 3. Dilution structure, 4. Mixing air duct emptying lift valve, 5. High-concentration exhaust gas pipeline, 6. High-concentration exhaust gas pipeline emptying lift valve, 7. High-concentration exhaust gas pipeline pneumatic butterfly valve, 8. High-concentration exhaust gas pipeline explosion venting plate, 9. Second pressure transmitter, 10. High-concentration exhaust gas pipeline pneumatic regulating valve, 11. First pressure transmitter, 12. Dilution air duct, 13. Mixing air duct explosion venting plate, 14. LEL concentration Detection device sampling port, 15. Mixing air duct, 16. Mixing air duct manual butterfly valve, 17. Mixing air duct, 18. Dispersion screen cylinder, 19. Swirl blade device, 20. Barrier box, 21. Barrier device, 22. Swirl blade, 23. Intermediate fixed cylinder, 24. Channel steel, 25. Barrier plate, 26. First pipeline, 27. Second pipeline, 28. Third pipeline, 29. Mixed air output pipeline, 30. Mixed air transport structure, 31. High-concentration exhaust gas transport structure. DETAILED DESCRIPTION

[0034] The utility model is further explained below in conjunction with the accompanying drawings and specific implementation methods.

[0035] Embodiment 1:

[0036] like Figure 1 and Figure 2 As shown, the high-concentration exhaust gas mixed air dilution device disclosed in the utility model comprises a dilution structure 3, one end of the dilution structure 3 is connected to a dilution air fan 1 for conveying dilution air, and the other end of the dilution structure 3 is sequentially connected to a mixed air output pipeline 29, a first pipeline 26, and a mixed air transport structure 30;

[0037] The dilution structure 3 includes a mixed air duct 17 and a baffle box 20 connected in sequence, the baffle box 20 is connected to the mixed air output duct 29, and the mixed air duct 17 is connected to a high-concentration exhaust gas transport structure 31;

[0038] A dispersion screen 18 and a swirl blade device 19 are sequentially arranged in the air mixing duct 17 along the air outlet direction of the dilution air fan 1;

[0039] The mixed air output duct 29 is provided with a mixed air duct explosion relief piece 13 for reducing explosion hazards;

[0040] The first pipe 26 is connected to a sampling port 14 of a LEL concentration detection device for obtaining LEL concentration.

[0041] The dilution air fan 1 blows the dilution air into the dilution structure 3 to mix it with the high-concentration exhaust gas blown into the high-concentration exhaust gas transport structure 31. The mixed air is passed through the mixed air output pipe 29, the first pipe 26, and the mixed air transport structure 30 into the mixed air treatment equipment for treatment. The sampling port 14 of the LEL concentration detection device on the first pipe 26 can be used to take samples for concentration detection.

[0042] Embodiment 2:

[0043] On the basis of Example 1, the air outlet of the dilution air fan 1 is connected to the mixing air duct 17 through the dilution air duct 12. The first pressure transmitter 11 and the dilution air duct pneumatic butterfly valve 2 are sequentially arranged on the outside of the dilution air duct 12 along the air outlet direction of the dilution air fan 1. The first pressure transmitter 11 is linked with the dilution air fan 1 to detect and adjust the air pressure at the fan outlet.

[0044] like Figure 2 As shown, the dispersion screen drum 18 is in an inverted T-shape, and a plurality of diversion holes are opened on the horizontal tube wall of the dispersion screen drum 18. One end of the horizontal pipe of the dispersion screen drum 18 is made into a 45-degree trumpet shape to connect to the dilution air pipe 12, and the other end of the horizontal pipe of the dispersion screen drum 18 is blind plate welded and blocked. The trumpet design of the dispersion screen drum 18 can make the dilution air blown in by the dilution air fan 1 directly blown into the high-concentration exhaust gas wind coming in from the high-concentration exhaust gas transport structure 31, so as to achieve a preliminary dilution purpose. The diversion holes can make the high-concentration exhaust gas wind dispersed into many small streams to be blown out for secondary mixing with the dilution air. The swirl blade device 19 includes an intermediate fixed cylinder 23, and 18-24 steel plates with a twist angle of about 20°-25° are fixedly connected to the intermediate fixed cylinder 23 to form swirl blades 22. The plurality of swirl blades 22 are evenly distributed along the circumference of the intermediate fixed cylinder 23, such as Figure 4 As shown, the ends of the multiple swirl blades 22 away from the middle fixed cylinder are fixedly connected with the outer ring of the blades, and the outer ring of the blades is fixedly connected to the air mixing duct 17. The swirl blades 22 can make the air flow rotate to achieve the purpose of three-time mixing;

[0045] like Figure 3 As shown, the barrier box 20 has a square pipe shape, and the inlet and outlet of the barrier box 20 are circular pipes. A barrier device 21 is fixedly connected to the central axis position of the barrier box 20 to block the high-concentration exhaust gas in the middle and allow it to diffuse around and mix more with the low-concentration exhaust gas. The barrier device 21 includes a channel steel 24 fixedly connected to the inner wall of the barrier box in a horizontal and vertical cross manner, and a barrier plate 25 fixedly connected to the channel steel 24 on the side close to the mixed air duct 17. The barrier plate 25 is a circular steel plate. The diameter of the circular steel plate should be close to or consistent with the size of the mixed air duct, and the center of the circular steel plate should also be coaxial with the center of the mixed air duct.

[0046] like Figure 5 As shown, the high-concentration exhaust gas transport structure 31 includes a high-concentration exhaust gas pipeline 5, one end of the high-concentration exhaust gas pipeline 5 is connected to a high-concentration exhaust gas pipeline pneumatic butterfly valve 7, the other end of the high-concentration exhaust gas pipeline pneumatic butterfly valve 7 is connected to a high-concentration exhaust gas pipeline pneumatic regulating valve 10 through a third pipeline 28, and the other end of the high-concentration exhaust gas pipeline pneumatic regulating valve 10 is connected to the vertical pipeline of the dispersion screen cylinder 18 through a pipeline.

[0047] The third pipeline 28 is connected to the second pressure transmitter 9. The third pipeline 28 is also provided with a high-concentration exhaust gas pipeline explosion relief plate 8 for reducing explosion hazards. The second pressure transmitter 9 and the high-concentration exhaust gas pipeline pneumatic regulating valve 10 form a linkage, and the wind pressure in the pipeline is maintained stable through pressure detection of the two and the action of the valve.

[0048] The high-concentration exhaust gas pipeline 5 is provided with a high-concentration exhaust gas pipeline emptying lifting valve 6 for directly discharging the high-concentration exhaust gas from the pipeline to prevent the pipeline from being blocked and affecting the production space. The high-concentration exhaust gas pipeline pneumatic butterfly valve 7 is linked with the exhaust gas treatment equipment and the high-concentration exhaust gas pipeline emptying lifting valve 6. When the treatment equipment is not started, the high-concentration exhaust gas pipeline pneumatic butterfly valve 7 is closed and the high-concentration exhaust gas pipeline emptying lifting valve 6 is opened.

[0049] like Figure 6 As shown, the fluid finite element analysis of the air mixing effect of the air mixing device is carried out. The numbers in the figure are the proportions of high-concentration exhaust gas and air after mixing (the original gas is 100% exhaust gas simulation), and the step distribution of gas concentration after mixing can be seen.

[0050] Embodiment 3:

[0051] Based on Example 1, the mixed air transport structure 30 includes a mixed air duct 15, a second pipeline 27 and a mixed air duct manual butterfly valve 16 connected in sequence, the mixed air duct 15 is connected to the first pipeline 26, and the mixed air duct manual butterfly valve 16 is connected to the exhaust gas treatment equipment through a pipeline.

[0052] The LEL concentration detection device is linked with the pneumatic butterfly valve 2 of the dilution air duct, the pneumatic butterfly valve 7 of the high-concentration exhaust gas pipeline and the high-concentration exhaust gas pipeline emptying lifting valve 6. When the LEL concentration detection device detects that the gas concentration exceeds the calibration gas concentration, its associated valve will be directly closed, and the high-concentration exhaust gas pipeline emptying lifting valve 6 will be directly opened to discharge the high-concentration exhaust gas.

[0053] The second pipe 27 is provided with a mixed air pipe exhaust lift valve 4 for exhausting the mixed air out of the pipe.

[0054] The distance A between the LEL concentration detection device and the outlet of the air mixing device should be greater than or equal to 6 times the pipe diameter, and the distance B between the sampling port of the LEL concentration detection device and the mixing duct exhaust lift valve 4 should meet the following requirements:

[0055] B=(T1+T2-T3)*V

[0056] Among them: T1 is the sampling detection feedback time of the LEL concentration detection device; T2 is the action time of opening the mixed air duct emptying lift valve 4; T3 is the flow time of the gas from the mixed air duct emptying lift valve 4 to the inlet stop valve of the processing equipment; V is the maximum value of the mixed air flow in the pipeline.

[0057] The above requirements are to prevent high-concentration exhaust gas from being directly sent into the processing equipment, thereby increasing the explosion risk of the processing equipment. In addition, the electrical accessories in the system are matched according to the explosion-proof requirements (the explosion-proof level is matched according to the actual location), and the valves use relatively safer pneumatic control methods.

Claims

1. High-concentration exhaust gas mixed air dilution device, characterized in that: It comprises a dilution structure (3), one end of the dilution structure (3) is connected to a dilution air fan (1) for conveying dilution air, and the other end of the dilution structure (3) is sequentially connected to a mixed air output pipeline (29), a first pipeline (26), and a mixed air transport structure (30); The dilution structure (3) comprises an air mixing duct (17) and a blocking box (20) connected in sequence, the blocking box (20) is connected to the mixed air output duct (29), and the air mixing duct (17) is connected to a high-concentration exhaust gas transport structure (31); A dispersion screen drum (18) and a swirl blade device (19) are sequentially arranged in the air mixing duct (17) along the air outlet direction of the dilution air fan (1); The mixed air output pipe (29) is provided with a mixed air pipe explosion relief piece (13); The first pipeline (26) is connected to a LEL concentration detection device.

2. The high-concentration exhaust gas mixed air dilution device according to claim 1, characterized in that: The air outlet of the dilution air fan (1) is connected to the air mixing duct (17) via a dilution air duct (12), and a first pressure transmitter (11) and a dilution air duct pneumatic butterfly valve (2) are sequentially arranged on the outside of the dilution air duct (12) along the air outlet direction of the dilution air fan (1).

3. The high-concentration exhaust gas mixed air dilution device according to claim 2 is characterized in that: The dispersion screen drum (18) is in an inverted T-shape, a plurality of diversion holes are opened on the horizontal tube wall of the dispersion screen drum (18), one end of the horizontal tube of the dispersion screen drum (18) is connected to the dilution air tube (12), and the other end of the horizontal tube of the dispersion screen drum (18) is in a blocked state, the swirl blade device (19) comprises an intermediate fixed tube (23), a plurality of swirl blades (22) are fixedly connected to the intermediate fixed tube (23), the plurality of swirl blades (22) are evenly distributed along the circumference of the intermediate fixed tube (23), the plurality of swirl blades (22) are fixedly connected to a blade outer ring at one end away from the intermediate fixed tube, and the blade outer ring is fixedly connected to the air mixing tube (17); A blocking device (21) is fixedly connected to the central axis of the blocking box (20), and the blocking device (21) comprises a channel steel (24) fixedly connected to the inner wall of the blocking box in a horizontal and vertical cross manner, and a blocking plate (25) fixedly connected to the side of the channel steel (24) close to the air mixing duct (17).

4. The high-concentration exhaust gas mixed air dilution device according to claim 3 is characterized in that: The high-concentration exhaust gas transport structure (31) comprises a high-concentration exhaust gas pipeline (5), one end of the high-concentration exhaust gas pipeline (5) is connected to a high-concentration exhaust gas pipeline pneumatic butterfly valve (7), the other end of the high-concentration exhaust gas pipeline pneumatic butterfly valve (7) is connected to a high-concentration exhaust gas pipeline pneumatic regulating valve (10) via a third pipeline (28), and the other end of the high-concentration exhaust gas pipeline pneumatic regulating valve (10) is connected to the vertical pipeline of the dispersion screen cylinder (18) via a pipeline.

5. The high-concentration exhaust gas mixed air dilution device according to claim 4, characterized in that: The outer side of the third pipeline (28) is connected to a second pressure transmitter (9), and the third pipeline (28) is also provided with a high-concentration exhaust gas pipeline explosion relief plate (8).

6. The high-concentration exhaust gas mixed air dilution device according to claim 4, characterized in that: The high-concentration exhaust gas pipeline (5) is provided with a high-concentration exhaust gas pipeline emptying lift valve (6).

7. The high-concentration exhaust gas mixed air dilution device according to claim 1, characterized in that: The mixed air transport structure (30) comprises a mixed air duct (15), a second pipeline (27) and a mixed air duct manual butterfly valve (16) which are connected in sequence, and the mixed air duct (15) is connected to the first pipeline (26).

8. The high-concentration exhaust gas mixed air dilution device according to claim 7, characterized in that: The second pipeline (27) is connected to a mixing air duct exhaust lift valve (4).

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