Purge gas ammonia recovery device

Abstract

The utility model discloses a purge gas ammonia recovery device which comprises an isobaric ammonia recovery tower, a cooling gas inlet pipe is arranged at the bottom of the isobaric ammonia recovery tower, and a cooling assembly is arranged on the cooling gas inlet pipe. A motor is arranged at the top of the isobaric ammonia recovery tower, a stirring shaft is mounted at the output end of the motor, and the stirring shaft is positioned in the isobaric ammonia recovery tower. A lifting pump is arranged on the outer side of the isobaric ammonia recovery tower, a spraying pipe is installed on the upper portion of the inner wall of the isobaric ammonia recovery tower, and an outlet of the lifting pump is communicated with the spraying pipe through a lifting pipe. The utility model relates to the technical field of synthesis ammonia production, in particular to an ammonia recovery device for purge gas, which can cool the purge gas by arranging the cooling mechanism, and the cooled purge gas enters the recovery tower and is subjected to ammonia absorption by water washing and spraying, so that the recovery efficiency of the recovery tower on ammonia gas in the purge gas can be improved, the concentration of ammonia water can be improved, and the recovery efficiency of ammonia gas in the purge gas can be improved. And the standard-exceeding emission of tail gas is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of synthetic ammonia production, in particular to a purge gas ammonia recovery device. Background Art

[0002] The liquid ammonia product produced by coal chemical synthetic ammonia enterprises is produced by the reaction of H2 and N2 raw gases under high temperature (490℃), high pressure (20MPa) and catalyst. The generated liquid ammonia is sent to the liquid ammonia storage tank (1.6MPa, 15℃). As the pressure drops and the ambient temperature rises, the dissolved H2 and N2 are released. In order to prevent the liquid ammonia spherical tank from overpressure, the pressure is vented. The vented air is called purge gas. In addition to H2 and N2, the purge gas also carries NH3 gas. In order to recover ammonia and prevent environmental pollution, an ammonia recovery tower is usually used to recover ammonia in the purge gas.

[0003] At present, the temperature of the exhaust gas is still relatively high. Absorbing ammonia at a relatively high temperature is not conducive to further increasing the concentration of ammonia water and reducing the ammonia content in the exhaust gas. Utility Model Content

[0004] 1. Technical issues to be resolved

[0005] In view of the deficiencies in the prior art, the utility model provides a purge gas ammonia recovery device, which solves the problem of low recovery efficiency of the prior purge gas ammonia recovery mechanism.

[0006] (II) Technical solution

[0007] To achieve the above-mentioned purpose, the utility model provides the following technical solutions: a purge gas ammonia recovery device, comprising an isobaric ammonia recovery tower, a cooling air inlet pipe is installed at the bottom of the isobaric ammonia recovery tower, and a cooling assembly is arranged on the cooling air inlet pipe.

[0008] A motor is arranged on the top of the isobaric ammonia recovery tower, and a stirring shaft is installed at the output end of the motor. The stirring shaft is located inside the isobaric ammonia recovery tower.

[0009] A lifting pump is arranged outside the isobaric ammonia recovery tower, a spray pipe is installed on the upper part of the inner wall of the isobaric ammonia recovery tower, and the outlet of the lifting pump is connected with the spray pipe through the lifting pipe.

[0010] A liquid inlet pipe is provided on the isobaric ammonia recovery tower.

[0011] A liquid discharge pipe is arranged at the bottom of the isobaric ammonia recovery tower, and an ammonia concentration detector and a first switch valve are respectively arranged on the liquid discharge pipe.

[0012] An exhaust port is arranged at the top of the isobaric ammonia recovery tower, and an ammonia detector and a second switch valve are respectively arranged on the exhaust port.

[0013] As a further preference, the cooling air inlet pipe comprises a cooling section, a necking section and a narrow-mouth section, a cooling cavity is arranged in the cooling section, and a water inlet and a water outlet are respectively arranged on the cooling cavity.

[0014] As further preferred, the cooling component includes a cold water tank, on which a pump is provided, the pump is connected to a water inlet through a water pipe, and a water outlet is connected to the cold water tank through a water pipe.

[0015] As a further preference, a water tank is provided outside the isobaric ammonia recovery tower, the water tank is filled with cold water, and a riser pipe runs through the water tank.

[0016] (III) Beneficial effects

[0017] The utility model provides a purge gas ammonia recovery device, which has the following beneficial effects:

[0018] The purge gas ammonia recovery device can cool the purge gas by arranging a cooling mechanism. The cooled purge gas enters a recovery tower and absorbs ammonia through water washing and spraying, thereby improving the recovery efficiency of the recovery tower for ammonia in the purge gas, increasing the concentration of ammonia water, and reducing excessive emissions of tail gas. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the structure of the utility model;

[0020] Figure 2 This is an enlarged view of the cooling air intake pipe structure of the utility model.

[0021] In the figure: 1. isobaric ammonia recovery tower; 2. cooling air inlet pipe; 21. cooling section; 211. cooling chamber; 212. water inlet; 213. water outlet; 22. necking section; 23. narrow section; 3. cold water tank; 4. pump; 5. water pipe; 6. motor; 7. stirring shaft; 8. lifting pump; 9. lifting pipe; 10. spray pipe; 11. liquid inlet pipe; 12. liquid discharge pipe; 13. ammonia concentration detector; 14. first switch valve; 15. exhaust port; 16. ammonia detector; 17. second switch valve; 18. water tank. DETAILED DESCRIPTION

[0022] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0023] like Figure 1-2As shown, the utility model provides a technical solution: a purge gas ammonia recovery device, comprising an isobaric ammonia recovery tower 1, a cooling air inlet pipe 2 is installed at the bottom of the isobaric ammonia recovery tower 1, and a cooling assembly is arranged on the cooling air inlet pipe 2.

[0024] The cooling air intake pipe 2 includes a cooling section 21, a constricted section 22 and a narrow section 23. The cooling section 21 has the largest diameter in order to increase the contact area between the cold water and the released air to achieve the purpose of cooling. A cooling cavity 211 is provided in the cooling section 21, and a water inlet 212 and a water outlet 213 are respectively provided on the cooling cavity 211.

[0025] The cooling component includes a cold water tank 3, on which a pump 4 is provided. The pump 4 is connected to a water inlet 212 through a water pipe 5, and a water outlet 213 is connected to the cold water tank 3 through the water pipe 5. Cold water enters from the water inlet 212, and the water after absorbing heat is discharged through the water outlet 213. After being cooled in the cold water tank 3, it is replenished again for recycling.

[0026] A motor 6 is arranged on the top of the isobaric ammonia recovery tower 1 , and a stirring shaft 7 is installed at the output end of the motor 6 . The stirring shaft 7 is located inside the isobaric ammonia recovery tower 1 .

[0027] A lifting pump 8 is arranged outside the isobaric ammonia recovery tower 1, and a spray pipe 10 is installed on the upper part of the inner wall of the isobaric ammonia recovery tower 1. The outlet of the lifting pump 8 is connected with the spray pipe 10 through the lifting pipe 9. A water tank 18 is arranged outside the isobaric ammonia recovery tower 1. The water tank 18 is filled with cold water. The lifting pipe 9 runs through the water tank 18. The lifting pipe 9 is also cooled when passing through the water tank 18.

[0028] The isobaric ammonia recovery tower 1 is provided with a liquid inlet pipe 11 .

[0029] A drain pipe 12 is provided at the bottom of the isobaric ammonia recovery tower 1, and an ammonia concentration detector 13 and a first switch valve 14 are provided on the drain pipe 12. After absorbing ammonia gas, the dilute ammonia water forms concentrated ammonia water with higher concentration, which can be sold.

[0030] An exhaust port 15 is provided at the top of the isobaric ammonia recovery tower 1 , and an ammonia detector 16 and a second switch valve 17 are respectively provided on the exhaust port 15 .

[0031] Meanwhile, the contents not described in detail in this specification belong to the prior art known to the professional and technical personnel in this field.

[0032] When in use, the purge gas enters the isobaric ammonia recovery tower 1 through the cooling air inlet pipe 2. The cold water tank 3 contains cold water, which is pumped into the cooling chamber 211 through the pump 4 and the water pipe 5, thereby cooling the purge gas flowing through the cooling air inlet pipe 2.

[0033] Dilute ammonia water is added into the isobaric ammonia recovery tower 1 through the liquid inlet pipe 11, the purge gas is mixed with the dilute ammonia water, and the ammonia in the purge gas is dissolved in the ammonia water. In order to further accelerate the process of ammonia dissolving in water, the motor 6 is turned on to drive the stirring shaft 7 to rotate to accelerate the dissolution.

[0034] After that, the purge gas rises from the bottom of the tower to the top, the lifting pump 8 is turned on, and the ammonia water enters the spray pipe 10 through the lifting pipe 9 and is sprayed out, contacting with the purge gas again, thereby completely absorbing the residual ammonia in the purge gas. The ammonia concentration at the outlet is detected by the ammonia detector 16. When it meets the standard, the second switch valve 17 is opened to discharge it.

[0035] The concentration of the ammonia water is detected by an ammonia water concentration detector 13. When the concentration of the ammonia water reaches the standard, the first switch valve 14 is opened to discharge the ammonia water.

[0036] In summary, the purge gas ammonia recovery device can cool the purge gas by arranging a cooling mechanism. The cooled purge gas enters the recovery tower and absorbs ammonia through water washing and spraying, thereby improving the recovery efficiency of the recovery tower for ammonia in the purge gas, increasing the concentration of ammonia water, and reducing excessive emissions of tail gas.

[0037] It should be noted that the electrical components appearing in this article are all connected to the external main controller and 220V or 380V mains electricity, and the main controller can be a conventional known device for controlling computers, etc. Its control principle, internal structure and control switch mode are all conventional means of the prior art, which are directly quoted here without further elaboration. In this article, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variant thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0038] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A purge gas ammonia recovery device, characterized in that: It comprises an isobaric ammonia recovery tower (1), a cooling air inlet pipe (2) is installed at the bottom of the isobaric ammonia recovery tower (1), and a cooling component is arranged on the cooling air inlet pipe (2); A motor (6) is arranged at the top of the isobaric ammonia recovery tower (1), a stirring shaft (7) is installed at the output end of the motor (6), and the stirring shaft (7) is located inside the isobaric ammonia recovery tower (1); A lifting pump (8) is arranged outside the isobaric ammonia recovery tower (1), a spray pipe (10) is installed on the upper part of the inner wall of the isobaric ammonia recovery tower (1), and the outlet of the lifting pump (8) is connected to the spray pipe (10) through the lifting pipe (9); The isobaric ammonia recovery tower (1) is provided with a liquid inlet pipe (11); A liquid discharge pipe (12) is arranged at the bottom of the isobaric ammonia recovery tower (1), and an ammonia concentration detector (13) and a first switch valve (14) are respectively arranged on the liquid discharge pipe (12); An exhaust port (15) is arranged at the top of the isobaric ammonia recovery tower (1), and an ammonia detector (16) and a second switch valve (17) are respectively arranged on the exhaust port (15).

2. A purge gas ammonia recovery device according to claim 1, characterized in that: The cooling air inlet pipe (2) comprises a cooling section (21), a necking section (22) and a narrow section (23); a cooling cavity (211) is provided in the cooling section (21); and a water inlet (212) and a water outlet (213) are respectively provided on the cooling cavity (211).

3. A purge gas ammonia recovery device according to claim 2, characterized in that: The cooling assembly comprises a cold water tank (3), on which a pump (4) is arranged, the pump (4) being connected to a water inlet (212) via a water pipe (5), and a water outlet (213) being connected to the cold water tank (3) via a water pipe (5).

4. A purge gas ammonia recovery device according to claim 1, characterized in that: A water tank (18) is arranged outside the isobaric ammonia recovery tower (1), the water tank (18) contains cold water, and a riser pipe (9) passes through the water tank (18).

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