Concentrating tower provided with wall flow prevention device and used for nitric acid production

Abstract

The utility model discloses a nitric acid production concentration tower provided with a wall flow prevention device, the upper part of the concentration tower is a rectifying section, the lower part of the concentration tower is a stripping section, and the concentration tower is characterized in that the wall flow prevention device is arranged in the rectifying section and comprises a chassis and an inclined flow guide ring plate, and the lower end of the flow guide ring plate is connected with the outer end of the chassis; the upper end of the flow guide ring plate is connected with the inner wall of the concentration tower, a plurality of through holes are formed in the flow guide ring plate, and the chassis and the flow guide ring plate form a big-end-up funnel shape. According to the wall-flow liquid collecting device, wall-flow liquid can be collected, gas rises through the through holes, the rising gas can heat and evaporate the collected liquid again, the liquid is prevented from flowing into next equipment, gas heat is fully utilized, the yield is increased, and energy consumption is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of nitric acid production, and particularly relates to a concentration tower for nitric acid production provided with an anti-wall flow device. Background Technique

[0002] Nitric acid is one of the important products in the basic chemical industry and also an important chemical raw material. The main way to produce concentrated nitric acid in industrial production is the magnesium nitrate water absorption method. After concentrated magnesium nitrate and dilute nitric acid are metered by a flow meter, they are mixed and enter a mixing distributor, and then enter the middle part of the concentration tower. The lower part of the nitric acid concentration tower is a stripping section, and the upper part is a rectifying section. After the concentrated magnesium nitrate solution absorbs the water in the dilute nitric acid, its concentration decreases, and it flows into the magnesium nitrate heater from the bottom of the tower. After being heated and denitrified, it flows into the dilute magnesium nitrate storage tank. The secondary steam generated by the magnesium nitrate heater enters the concentration tower from the bottom of the concentration tower to provide the heat source for the concentration tower.

[0003] The mixture is distilled in the concentration tower. Nitric acid vapor with a content of 85% - 90% enters the rectifying section from the stripping section and is concentrated into nitric acid vapor with a concentration of more than 98%. The nitric acid vapor enters the concentrated nitric acid condenser and is condensed into concentrated nitric acid. After being separated by a gas-liquid separator, the acid enters the distribution acid seal. The non-condensable gas is subjected to negative pressure recovery by a tower tail ejector to generate acidic water, and the acidic water enters the tower tail water circulation tank for recycling. About 1 / 2 of the concentrated nitric acid returns to the concentration tower as reflux acid, and about 1 / 2 of the concentrated nitric acid enters the bleaching tower through the bleaching acid seal. The air heated by the air heater removes nitrite and then enters the finished acid tank area as the finished acid.

[0004] After nitric acid evaporates in the concentration tower and encounters the low-temperature tower wall, the gas is condensed into a liquid, and the liquid flows down along the tower wall to the bottom of the tower, causing wall flow. After the wall flow occurs, the effective gas decreases, the output decreases, and after the liquid wall flows to the bottom of the tower and enters the magnesium nitrate heater, the nitric acid that has already been vaporized is reheated again, resulting in waste of steam and energy consumption. Content of the Utility Model

[0005] The purpose of the utility model is to provide a concentration tower for nitric acid production provided with an anti-wall flow device to solve the problems existing in the background technique.

[0006] To achieve the above purpose, the utility model provides the following technical solution: A concentration tower for nitric acid production provided with an anti-wall flow device, the upper part of the concentration tower is a rectifying section, and the lower part is a stripping section. An anti-wall flow device is arranged inside the rectifying section. The anti-wall flow device includes a chassis and a diversion ring plate arranged obliquely. The lower end of the diversion ring plate is connected to the outer end of the chassis, the upper end of the diversion ring plate is connected to the inner wall of the concentration tower, a plurality of through holes are arranged on the diversion ring plate, and the chassis and the diversion ring plate form a funnel shape with a large upper part and a small lower part.

[0007] As a preference of this technical solution, the included angle between the diversion ring plate and the inner wall of the concentration tower is 30 - 50°.

[0008] Preferably, as a technical solution of the present invention, the anti-wall flow device is arranged between the tower sections of the concentration tower.

[0009] Preferably, as a technical solution of the present invention, the through holes are evenly distributed on the flow guiding ring plate.

[0010] Preferably, as a technical solution of the present invention, the minimum distance between the through hole and the chassis is 2-10 mm.

[0011] Preferably, as a technical solution of the present invention, a gas outlet is arranged at the upper end of the concentration tower, a liquid outlet is arranged at the lower end of the concentration tower, and a liquid inlet is arranged in the middle of the concentration tower.

[0012] Compared with the prior art, the present invention has the following beneficial effects: By arranging an anti-wall flow device in the concentration tower, the liquid flowing along the wall can be collected. The gas rises through the through holes, and the rising gas can reheat and evaporate the collected liquid, preventing the liquid from flowing into the next device, making full use of the gas heat, increasing the output, and reducing the energy consumption. Description of the Drawings

[0013] Figure 1 It is a structural schematic diagram of the present invention.

[0014] Figure 2 It is a structural schematic diagram of the anti-wall flow device of the present invention.

[0015] In the figure: 1, concentration tower; 2, chassis; 3, flow guiding ring plate; 3.1, through hole; 4, gas outlet; 5, liquid inlet; 6, liquid outlet. Detailed Embodiments

[0016] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0017] Please refer to Figure 1-2 , a concentration tower for nitric acid production provided with an anti-wall flow device according to the present invention. The upper part of the concentration tower 1 is a rectifying section, and the lower part is a stripping section. A gas outlet 4 is arranged at the upper end of the concentration tower 1, a liquid outlet 6 is arranged at the lower end of the concentration tower 1, and a liquid inlet 5 is arranged in the middle of the concentration tower 1. An anti-wall flow device is arranged inside the rectifying section. The anti-wall flow device includes a chassis 2 and an inclined flow guiding ring plate 3. The lower end of the flow guiding ring plate 3 is connected to the outer end of the chassis 2, the upper end of the flow guiding ring plate 3 is connected to the inner wall of the concentration tower 1, and a plurality of through holes 3.1 are arranged on the flow guiding ring plate 3. The chassis 2 and the flow guiding ring plate 3 form a funnel shape with a larger upper part and a smaller lower part.

[0018] When the specific implementation of the utility model is carried out, the anti-wall-flow device is arranged between the tower sections of the rectifying section of the concentrating tower 1. The guiding ring plate 3 of the anti-wall-flow device is connected to the inner wall of the concentrating tower 1. The liquid flowing along the wall is redirected to flow towards the chassis 2. The chassis 2 is arranged horizontally, and the cross-sectional area of the chassis 2 is smaller than that of the concentrating tower 1. The chassis 2 is arranged at the center of the cross-section of the concentrating tower. The included angle between the guiding ring plate 3 and the inner wall of the concentrating tower 1 is 30-50°, and this included angle refers to the acute angle between the two. The diameter of the through holes 3.1 can be controlled so that the gas can pass through and the liquid cannot leak a large amount from the through holes due to the relatively fast flow rate. The through holes 3.1 are evenly distributed on the guiding ring plate 3. The minimum distance between the through holes 3.1 and the chassis 2 is 2-10 mm, and this distance is the distance from the through hole 3.1 closest to the chassis 2 to the chassis 2.

[0019] Finally, it should be noted that: the above-mentioned embodiments are only specific implementation manners of the utility model, which are used to illustrate the technical solutions of the utility model, rather than to limit it. The protection scope of the utility model is not limited thereto. Although the utility model has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: any person skilled in the art within the technical scope disclosed by the utility model can still modify the technical solutions recorded in the foregoing embodiments, or can easily think of changes, or perform equivalent replacements on some of the technical features; and these modifications, changes or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the utility model, and should all be covered within the protection scope of the utility model. Therefore, the protection scope of the utility model should be subject to the protection scope of the claims.

Claims

1. A concentration tower for nitric acid production provided with a wall flow prevention device, wherein the upper part of the concentration tower is a rectifying section and the lower part is a stripping section, characterized in that: A wall flow prevention device is arranged inside the distillation section, and the wall flow prevention device comprises a bottom plate and an inclined guide ring plate, wherein the lower end of the guide ring plate is connected to the outer end of the bottom plate, and the upper end of the guide ring plate is connected to the inner wall of the concentration tower, and a plurality of through holes are arranged on the guide ring plate, so that the bottom plate and the guide ring plate form a funnel shape with a larger upper part and a smaller lower part.

2. The concentration tower for nitric acid production according to claim 1, characterized in that: The included angle between the guide ring plate and the inner wall of the concentration tower is 30-50°.

3. The concentration tower for nitric acid production according to claim 2, characterized in that: The wall flow prevention device is arranged between the tower sections of the concentration tower.

4. The concentration tower for nitric acid production according to claim 1, characterized in that: The through holes are evenly distributed on the guide ring plate.

5. The concentration tower for nitric acid production according to claim 1, characterized in that: The minimum distance between the through hole and the chassis is 2-10 mm.

6. The concentration tower for nitric acid production according to claim 1, characterized in that: The upper end of the concentrating tower is provided with a gas outlet, the lower end of the concentrating tower is provided with a liquid outlet, and the middle part of the concentrating tower is provided with a liquid inlet.

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