Tail gas absorption tower for heavy benzol rectification tail gas treatment

Abstract

The utility model relates to the technical field of tail gas treatment, in particular to a tail gas absorption tower for heavy benzol rectification tail gas treatment. Comprising a tower body, a cooling assembly is arranged at the lower end of the tower body, a lower filter screen is fixed in the tower body above the cooling assembly, an air inlet pipe is fixedly communicated with the tower body above the lower filter screen, a water curtain treatment assembly is arranged in the tower body above the air inlet pipe, the tower body above the water curtain treatment assembly is filled with filler, and a spraying assembly is arranged in the tower body above the filler. The spraying assembly is partially communicated with the tower body above the lower filter screen through a conveying assembly, and an interception assembly is arranged in the tower body above the spraying assembly. By arranging the cooling assembly, the cooling assembly can cool the absorption liquid in the lower end of the tower body, and the amount of absorption liquid steam can be reduced, so that the generation amount of the absorption liquid steam is reduced, the amount of the absorption liquid entering subsequent tail gas treatment equipment is reduced, and the working pressure of the subsequent tail gas treatment equipment is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of tail gas treatment, in particular to a tail gas absorption tower for treating tail gas from heavy benzene distillation. Background Art

[0002] In order to overcome the environmental pollution caused by direct emission and incineration of heavy benzene distillation tail gas from heavy benzene distillation unit, it is necessary to set up a tail gas absorption tower to treat the tail gas of heavy benzene distillation. The tail gas of heavy benzene distillation includes cyclopentadiene, low boiling point alkanes, benzene, toluene, carbon disulfide, thiophene, xylene, styrene, indene and naphthalene. The tail gas absorption tower can be used with methylnaphthalene absorption liquid to absorb the harmful gases in the tail gas of heavy benzene distillation discharged from the heavy benzene distillation unit, and the absorption rate can reach 90%.

[0003] Existing tail gas absorption towers, such as the patent document with application number CN201721251967.2 and titled "A Tail Gas Absorption Tower", disclose a packed tower for absorbing tail gas. The tail gas absorption tower absorbs the tail gas entering through the bottom of the tower, and the tail gas is evenly distributed and ascended through the support plate. The alkali solution is evenly sprayed from the top of the tower using an alkali spray nozzle, which fully contacts the tail gas and absorbs the substances to be washed in the rising gas, which then flows down and is discharged from the alkali solution reflux pipe at the bottom of the tower, making full use of the spraying to make the tail gas absorption more complete. However, the tail gas absorption tower only relies on the uniform distribution of the support plate, and the sprayed alkali solution cannot be fully mixed with the tail gas, so the harmful substances in the tail gas are not completely absorbed.

[0004] The patent document with application number CN201821360321.2 and titled "A Glass Fiber Reinforced Plastic Tail Gas Absorption Tower" discloses a tail gas absorption tower that can improve the mixing efficiency of tail gas and absorption liquid. The tail gas absorption tower body includes a first packing layer, a second packing layer and a lower air chamber, and an annular spray pipe is provided on the top of the first packing layer and the second packing layer. The tail gas absorption tower is provided with two layers of packing layers in the tower body, so that the tail gas and the absorption liquid can be fully mixed, and the removal rate of harmful substances in the tail gas can be improved. However, the provision of two layers of packing layers is likely to lead to large upward resistance of the tail gas, and the tail gas pressure needs to be increased. When dealing with flammable tail gas, the cost of pressurizing the tail gas is high.

[0005] At the same time, some existing tail gas absorption towers cannot effectively recover the absorption liquid sprayed on the top of the tower. The sprayed absorption liquid is easily discharged from the top of the tower along with the tail gas and enters the subsequent processing equipment, increasing the working pressure of the subsequent processing equipment. Utility Model Content

[0006] The technical problem to be solved by the utility model is a tail gas absorption tower which can improve the mixing effect of absorption liquid and tail gas and can effectively cool the absorption liquid. The tail gas absorption tower can intercept the absorption liquid vapor and reduce the amount of absorption liquid entering the subsequent tail gas treatment equipment.

[0007] In order to achieve the above purpose, the technical solution provided by the utility model is:

[0008] A tail gas absorption tower for treating tail gas from heavy benzene distillation comprises a tower body, a cooling assembly is arranged at the lower end of the tower body, a lower filter is fixed in the tower body above the cooling assembly, an air inlet pipe is fixedly connected to the tower body above the lower filter, a water curtain treatment assembly is arranged in the tower body above the air inlet pipe, the tower body above the water curtain treatment assembly is filled with fillers, a spray assembly is arranged in the tower body above the fillers, the spray assembly is connected with the tower body part above the lower filter through a conveying assembly, and an interception assembly is arranged in the tower body above the spray assembly.

[0009] Specifically, the cooling assembly includes a cooling pipe, which is located in the tower body below the lower filter screen and is connected to a refrigerator. The cooling assembly can cool the absorption liquid in the lower end of the tower body and reduce the amount of absorption liquid vapor.

[0010] Specifically, the water curtain treatment assembly includes a plurality of arc plates, which are evenly distributed along the axial direction of the tower body, the arc plates are fixedly and sealedly connected to the inner wall of the tower body, gaps are provided between the arc plates and the inner wall of the tower body, and the two gaps adjacent to each other are staggered, guide plates are fixed on the opposite end faces of the two adjacent arc plates, the guide plates between the two adjacent arc plates are staggered, slots are opened on the arc plates, porous plates are fixed in the slots, and the two adjacent porous plates are correspondingly arranged.

[0011] Specifically, lower grid plates are fixed in the tower body on both sides of the upper and lower sides of the filler, and the filler is filled between the two lower grid plates.

[0012] Specifically, the spray assembly includes a spiral tube, which is fixed in the tower body, and the lower end of the spiral tube is fixedly connected to a plurality of spray heads.

[0013] Specifically, the conveying assembly includes a connecting pipe connected to the spiral pipe, a liquid pump is installed on the connecting pipe, the liquid pump is fixed on the outside of the tower body, and the liquid inlet end of the connecting pipe is connected to the tower body above the lower filter screen.

[0014] Specifically, the interception assembly includes two upper grid plates fixed in the tower body, the two upper grid plates are arranged up and down, a plurality of baffles are fixed between the two upper grid plates, a baffle channel is formed between two adjacent baffles, and the bends of the two adjacent baffles are connected by an upper filter.

[0015] Compared with the prior art, the beneficial effects of the utility model are:

[0016] 1. The utility model is provided with a cooling component, which can cool the absorption liquid in the lower end of the tower body, thereby reducing the amount of absorption liquid vapor, thereby reducing the amount of absorption liquid vapor generated, reducing the amount of absorption liquid entering the subsequent exhaust gas treatment equipment, and reducing the working pressure of the subsequent exhaust gas treatment equipment.

[0017] 2. By setting up a water curtain treatment component, a water curtain is formed between two adjacent arc plates. The exhaust gas passes through the water curtain during the flow between the two adjacent arc plates, which can ensure that the exhaust gas and the absorption liquid are fully mixed. The guide plate can make the exhaust gas bend between the two adjacent arc plates, which can increase the contact area and contact time between the exhaust gas and the water curtain, and improve the absorption rate of the absorption liquid on harmful substances in the exhaust gas.

[0018] 3. By setting up the interception component, the tail gas passing through the filler and the spray component is deflected and upward when passing through the deflection channel, so that the absorption liquid droplets in the tail gas passing through the filler and the spray component can be gathered on the deflection plate to form droplets and drip, which can intercept the absorption liquid vapor, reduce the amount of absorption liquid entering the subsequent tail gas treatment equipment, and reduce the workload of the subsequent tail gas treatment equipment. At the same time, the setting of the upper filter can further accelerate the aggregation effect of the absorption liquid droplets in the tail gas.

[0019] 4. The utility model does not need to increase the tail gas pressure, and has high safety in the process of treating the tail gas from the distillation of heavy benzene. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a schematic diagram of the tail gas absorption tower.

[0021] Figure 2 for Figure 1 Magnified view of area A.

[0022] Figure 3 It is a schematic diagram of the coordination between the baffle plate and the upper filter plate.

[0023] Figure 4 Schematic diagram of the curved plate inside the tower body.

[0024] The names of the parts in the attached drawings are:

[0025] 1 tower body

[0026] 2 Intake pipe

[0027] 3. Material tube

[0028] 4 Lower filter

[0029] 5 Cooling pipe

[0030] 6 Refrigeration machine

[0031] 7 Connecting pipe

[0032] 8 Liquid pump

[0033] 9 Spiral tube

[0034] 10 Nozzle

[0035] 11 Curved plate

[0036] 12 Multiwell Plate

[0037] 13 Deflector

[0038] 14 Lower grille plate

[0039] 15 Filling

[0040] 16 Upper grille plate

[0041] 17 Baffle

[0042] 18 Upper filter

[0043] 19 Overflow weir. DETAILED DESCRIPTION

[0044] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments.

[0045] Embodiment 1:

[0046] Reference Figure 1-Figure 4 As shown, the tail gas absorption tower for treating the tail gas from the distillation of heavy benzene includes a tower body 1, and a cooling assembly is arranged at the lower end of the tower body 1. A lower filter screen 4 is fixed in the tower body 1 above the cooling assembly, an air inlet pipe 2 is fixedly connected to the tower body 1 above the lower filter screen 4, and a material pipe 3 is fixedly connected to the tower body 1 below the lower filter screen 4. An absorption liquid can be injected into the lower end of the tower body 1 through the material pipe 3. In this embodiment, the absorption liquid is methylnaphthalene.

[0047] A water curtain treatment assembly is arranged in the tower body 1 above the air inlet pipe 2. The tower body 1 above the water curtain treatment assembly is filled with fillers 15. Specifically, lower grid plates 14 are fixed in the tower body 1 on both sides of the fillers 15, and the fillers 15 are filled between the two lower grid plates 14.

[0048] A spray assembly is arranged in the tower body 1 above the filler 15. The spray assembly is communicated with the part of the tower body 1 above the lower filter screen 4 through a conveying assembly. A retention assembly is arranged in the tower body 1 above the spray assembly.

[0049] The cooling assembly includes a cooling pipe 5, which is located in the tower body 1 below the lower filter screen 4, and is connected to a refrigerator 6. The refrigerator 6 can allow the heat transfer medium to flow in the cooling pipe 5 and cool the absorption liquid in the lower end of the tower body 1, thereby reducing the amount of absorption liquid vapor generated, reducing the amount of absorption liquid entering the subsequent exhaust gas treatment equipment, and reducing the working pressure of the subsequent exhaust gas treatment equipment.

[0050] The water curtain treatment assembly includes a plurality of arc plates 11, which are evenly distributed along the axial direction of the tower body 1, and the arc plates 11 are fixedly sealed and connected to the inner wall of the tower body 1. A gap is provided between the arc plates 11 and the inner wall of the tower body 1, and an overflow weir 19 is provided at the end of the arc plate 11 on one side of the gap. The two gaps adjacent to each other are staggered. In this embodiment, the two gaps adjacent to each other are staggered in the left-right direction in the tower body 1.

[0051] The opposite end surfaces of the two adjacent arc plates 11 are fixed with guide plates 13, and the guide plates 13 between the two adjacent arc plates 11 are staggered. The guide plates 13 are perpendicular to the arc plates 11, and the two adjacent guide plates 13 are parallel. The arc plates 11 are provided with slots, and the slots are fixed with porous plates 12, and the two adjacent porous plates 12 are arranged correspondingly.

[0052] The absorption liquid sprayed from the spray assembly flows downward after passing through the filler 15. The absorption liquid discharged from the lower end of the filler 15 enters the arc plate 11 and flows downward through the porous plate 12, forming a water curtain between two adjacent arc plates 11.

[0053] The tail gas from the distillation of heavy benzene ascends in the tower body 1 through the air inlet pipe 2, and the tail gas flows in a serpentine shape between the multiple curved plates 11. The tail gas passes through the water curtain while flowing between two adjacent curved plates 11, which can ensure that the tail gas and the absorption liquid are fully mixed. The guide plate 13 can cause the tail gas to be deflected again between the two adjacent curved plates 11, which can increase the contact area and contact time between the tail gas and the water curtain, and improve the absorption rate of the absorption liquid to the harmful substances in the tail gas. After passing through the water curtain, the tail gas is mixed again in the packing 15 with the absorption liquid flowing downward in the packing 15, further ensuring the absorption rate of the absorption liquid to the harmful substances in the tail gas.

[0054] The spray assembly includes a spiral tube 9 which is fixed in the tower body 1 , and a plurality of spray heads 10 are fixedly connected to the lower end of the spiral tube 9 .

[0055] The conveying assembly includes a connecting pipe 7 connected to the spiral pipe 9 , a liquid pump 8 is installed on the connecting pipe 7 , and the liquid pump 8 is fixed on the outside of the tower body 1 . The liquid inlet end of the connecting pipe 7 is connected to the tower body 1 above the lower filter screen 4 .

[0056] The liquid pump 8 is started, and the liquid pump 8 can pump the absorption liquid in the lower end of the tower body 1 into the spiral tube 9 through the connecting pipe 7 and then spray it out through the nozzle 10.

[0057] The interception assembly includes two upper grid plates 16 fixed in the tower body 1 . The two upper grid plates 16 are arranged up and down. A plurality of baffles 17 are fixed between the two upper grid plates 16 . A baffle channel is formed between two adjacent baffles 17 .

[0058] The exhaust gas passing through the packing 15 and the spray assembly is deflected upward when passing through the deflection channel, so that the absorption liquid droplets in the exhaust gas passing through the packing 15 and the spray assembly can gather on the deflection plate 17 to form droplets and drip, which can intercept the absorption liquid vapor, reduce the amount of absorption liquid entering the subsequent exhaust gas treatment equipment, and reduce the workload of the subsequent exhaust gas treatment equipment.

[0059] Embodiment 2:

[0060] Based on Example 1, refer to Figure 3 As shown, the bends of two adjacent baffles 17 are connected by an upper filter screen 18. The setting of the upper filter screen 18 can further accelerate the aggregation effect of the absorption liquid droplets in the tail gas. In this embodiment, the absorption liquid droplets in the tail gas can not only be aggregated on the baffle 17 but also on the upper filter screen 18. The interception rate of the absorption liquid droplets in the tail gas can be increased.

[0061] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A tail gas absorption tower for treating tail gas from heavy benzene distillation, comprising a tower body (1), characterized in that: A cooling assembly is arranged at the lower end of the tower body (1); a lower filter screen (4) is fixed in the tower body (1) above the cooling assembly; an air intake pipe (2) is fixedly connected to the tower body (1) above the lower filter screen (4); a water curtain treatment assembly is arranged in the tower body (1) above the air intake pipe (2); a filler (15) is filled in the tower body (1) above the water curtain treatment assembly; a spray assembly is arranged in the tower body (1) above the filler (15); the spray assembly is connected to the tower body (1) part above the lower filter screen (4) through a conveying assembly; and a retention assembly is arranged in the tower body (1) above the spray assembly.

2. The tail gas absorption tower for treating the tail gas from the heavy benzene distillation according to claim 1, characterized in that: The cooling assembly comprises a cooling pipe (5), the cooling pipe (5) is located in the tower body (1) below the lower filter screen (4), and the cooling pipe (5) is connected to a refrigerator (6).

3. The tail gas absorption tower for treating heavy benzene distillation tail gas according to claim 1, characterized in that: The water curtain treatment assembly comprises a plurality of arc plates (11), the plurality of arc plates (11) are evenly distributed along the axial direction of the tower body (1), the arc plates (11) are fixedly sealed and connected to the inner wall of the tower body (1), a gap is provided between the arc plates (11) and the inner wall of the tower body (1), two gaps adjacent to each other are staggered, guide plates (13) are fixed to the opposite end surfaces of the two arc plates (11) adjacent to each other, the guide plates (13) between the two adjacent arc plates (11) are staggered, a slot is provided on the arc plate (11), a porous plate (12) is fixed in the slot, and the two porous plates (12) adjacent to each other are arranged correspondingly.

4. The tail gas absorption tower for treating the tail gas from the heavy benzene distillation according to claim 3, characterized in that: The guide plate (13) is perpendicular to the arc-shaped plate (11), and two adjacent guide plates (13) are parallel.

5. The tail gas absorption tower for treating the tail gas from heavy benzene distillation according to claim 3, characterized in that: An overflow weir (19) is provided at the end of the arc-shaped plate (11) on one side of the gap.

6. The tail gas absorption tower for treating the tail gas from heavy benzene distillation according to claim 1, characterized in that: Lower grid plates (14) are fixed in the tower body (1) on both upper and lower sides of the filler (15), and the filler (15) is filled between the two lower grid plates (14).

7. The tail gas absorption tower for treating the tail gas from heavy benzene distillation according to claim 1, characterized in that: The spray assembly comprises a spiral tube (9), which is fixed in the tower body (1), and the lower end of the spiral tube (9) is fixedly connected to a plurality of spray heads (10).

8. The tail gas absorption tower for treating the tail gas from heavy benzene distillation according to claim 7, characterized in that: The conveying assembly comprises a connecting pipe (7) connected to the spiral pipe (9), a liquid pump (8) is installed on the connecting pipe (7), the liquid pump (8) is fixed on the outside of the tower body (1), and the liquid inlet end of the connecting pipe (7) is connected to the tower body (1) above the lower filter screen (4).

9. The tail gas absorption tower for treating tail gas from heavy benzene distillation according to claim 1, characterized in that: The interception assembly comprises two upper grid plates (16) fixed in the tower body (1), the two upper grid plates (16) being arranged up and down, a plurality of baffles (17) being fixed between the two upper grid plates (16), a baffle channel being formed between two adjacent baffles (17), and the bends of the two adjacent baffles (17) being connected via an upper filter screen (18).

10. The tail gas absorption tower for treating tail gas from heavy benzene distillation according to claim 1, characterized in that: A material pipe (3) is fixedly connected to the tower body (1) below the lower filter screen (4).

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