An ammonia recovery device for a blowdown tank

Abstract

The application discloses an ammonia recovery device for a blowdown tank, and relates to the technical field of ammonia recovery, which comprises a tapered pipe arranged between the blowdown tank and a washing tank, the large end of the tapered pipe is communicated with the blowdown tank to receive gaseous ammonia, and the small end of the tapered pipe is tangentially and radially communicated with the side of the washing tank to deliver the gaseous ammonia and make the gaseous ammonia form a rotating airflow in the washing tank. The gaseous ammonia forms a rotating airflow in the washing tank through the tapered pipe, which not only makes the gaseous ammonia uniformly distributed in the washing tank, improves the utilization rate of water mist, but also increases the contact time of the gaseous ammonia with the water mist in the washing tank, and improves the ammonia recovery rate.

Description

Technical Field

[0001] This application relates to the field of ammonia recovery technology, specifically to an ammonia recovery device for a sewage tank. Background Technology

[0002] In the synthetic ammonia production industry, the synthesis wastewater tank is mainly used to collect liquid ammonia discharged from ammonia coolers in various process sections. This liquid ammonia is then converted into gaseous ammonia through heating and stripping, and then transported to the flare system for combustion. However, when the gaseous ammonia is not fully combusted, a certain amount of nitrogen oxides (NOx) are generated. x This causes air pollution. Furthermore, directly burning ammonia gas, which has recycling value, not only wastes ammonia resources but also contradicts the current industrial development orientation of green, low-carbon, energy-saving, and emission-reduction.

[0003] In response, Chinese utility model patent CN216171229U proposes an ammonia recovery device. This device guides ammonia gas into a recovery chamber via a recovery component and uses nozzles to spray water mist to dissolve the ammonia, thereby generating ammonia water and achieving resource recovery of ammonia. While this solution provides a feasible recovery approach, it still has significant shortcomings in practical applications: because ammonia gas is less dense than air, it rapidly disperses upwards after entering the recovery chamber. On the one hand, the lack of an effective distribution or guiding structure during dispersion leads to localized oversaturation of water mist while other areas fail to fully utilize the water mist, resulting in low overall water mist utilization efficiency. On the other hand, it significantly shortens the effective contact time between ammonia gas and water mist, reducing mass transfer efficiency and absorption effect, thus affecting the ammonia recovery rate and failing to meet the requirements of efficient and stable operation for industrial-grade recovery devices. Therefore, this issue urgently needs to be addressed. Utility Model Content

[0004] In order to overcome the above-mentioned technical problems, the purpose of this application is to provide an ammonia recovery device for a sewage tank. By using a converging tube, gaseous ammonia is formed into a rotating airflow in the washing tank, which not only makes it evenly distributed in the washing tank and improves the water mist utilization rate, but also increases the contact time between gaseous ammonia and water mist in the washing tank, thereby improving the gaseous ammonia recovery rate.

[0005] The objective of this application can be achieved through the following technical solutions: Specifically, an ammonia recovery device for a sludge tank is provided, including a converging tube disposed between the sludge tank and the washing tank. The large end of the converging tube is connected to the sludge tank to receive gaseous ammonia, and the small end of the converging tube is radially tangent to and connected to the side of the washing tank to transport gaseous ammonia and form a rotating airflow in the washing tank.

[0006] As a further aspect of this application: a demineralized water inlet pipe and an ammonia water recovery pipe are respectively arranged at the top and bottom of the washing tank. The demineralized water inlet pipe is used to transport the demineralized water to the inner cavity of the washing tank. The demineralized water comes into contact with the gaseous ammonia in the inner cavity of the washing tank to form ammonia water, which is then recovered through the ammonia water recovery pipe.

[0007] As a further aspect of this application: the side wall of the sewage tank is provided with a sewage inlet, and the inner wall of the sewage tank near the sewage inlet is provided with a downward-opening guide hood.

[0008] As a further aspect of this application: an air jet pipe is arranged in the inner cavity of the washing tank near the converging tube, and the air jet pipe is connected to the converging tube.

[0009] As a further aspect of this application: a spray pipe is arranged in the inner cavity of the washing tank near the demineralized water inlet pipe, and the spray pipe is connected to the demineralized water inlet pipe.

[0010] As a further aspect of this application, a desalination water inlet control valve is provided on the desalination water inlet pipe.

[0011] As a further aspect of this application: a shielded pump is installed on the ammonia recovery pipe.

[0012] As a further aspect of this application: the side wall of the sewage tank is provided with a sewage inlet, and the top and bottom of the sewage tank are respectively provided with a gas outlet and a discharge port, and the gas outlet is connected to a converging pipe.

[0013] As a further aspect of this application, the side wall of the sewage tank is also provided with a steam inlet and a nitrogen inlet.

[0014] The beneficial effects of this application are: 1. In this application, by using a converging tube installed between the sludge tank and the washing tank, when the gaseous ammonia formed in the sludge tank enters through the large end of the converging tube, the converging tube significantly increases the flow velocity of the gaseous ammonia at the small end by means of the Venturi effect, allowing the gaseous ammonia to enter the inner cavity of the washing tank at a higher flow rate and form a stable rotating airflow therein. This flow pattern promotes the uniform distribution of gaseous ammonia in the washing tank, ensuring that it is fully mixed with the demineralized water transported by the demineralized water inlet pipe, thereby greatly improving the utilization efficiency of the demineralized water. On the other hand, the formation of the rotating airflow significantly prolongs the residence path and time of gaseous ammonia in the washing tank, enhances the contact and reaction opportunities between gaseous ammonia and demineralized water, effectively improves the absorption efficiency of gaseous ammonia by the demineralized water, and thus improves the overall ammonia recovery rate.

[0015] 2. In this application, by coordinating the sewage tank and the washing tank, demineralized water is used to efficiently absorb gaseous ammonia. This not only achieves the effective removal and recovery of ammonia components from gaseous ammonia, but also allows the remaining non-condensable waste gas to be safely discharged and burned through a flare tube. This structure not only realizes the recycling of ammonia water resources, creating considerable economic benefits, but also significantly reduces the direct combustion of gaseous ammonia, thus achieving the dual effects of energy conservation, emission reduction, and environmental protection.

[0016] 3. In this application, by setting a flow guide, when the waste liquid is conveyed from the sewage inlet to the sewage tank, the flow guide can make the waste liquid form a vertically downward fluid, so as to avoid affecting the gaseous ammonia formed in the sewage tank. Attached Figure Description

[0017] The present application will be further described below with reference to the accompanying drawings.

[0018] Figure 1 This is a schematic diagram of an ammonia recovery device for a sewage tank according to this application; Figure 2 This is a schematic diagram of the washing tank in an ammonia recovery device for a sewage tank according to this application; Figure 3 This is a schematic diagram of the structure of the sewage tank in an ammonia recovery device for a sewage tank according to this application.

[0019] Explanation of reference numerals in the attached diagram: 1. Sewage tank; 11. Sewage inlet; 111. Flow deflector; 12. Gas outlet; 13. Exhaust port; 14. Steam inlet; 15. Nitrogen inlet; 16. Manhole; 17. Level gauge port; 18. Level switch port; 19. Pressure gauge port; 2. Washing tank; 21. Jet nozzle; 22. Spray pipe; 3. Converging pipe; 4. Demineralized water inlet pipe; 41. Demineralized water inlet control valve; 5. Ammonia recovery pipe; 6. Flare pipe; 7. Shielded pump. Detailed Implementation

[0020] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0021] As one embodiment of this application, such as Figures 1-3As shown, an ammonia recovery device for a sewage tank is disclosed, comprising a sewage tank 1 and a washing tank 2 connected to each other. Specifically, a converging pipe 3 is installed between the sewage tank 1 and the washing tank 2. The larger end of the converging pipe 3 is connected to the top of the sewage tank 1, and the smaller end of the converging pipe 3 is connected to the bottom end of the side wall of the washing tank 2, and is radially tangent to the side wall of the washing tank 2. The sewage tank 1 is used to transport gaseous ammonia to the inner cavity of the washing tank 2 through the converging pipe 3. A demineralized water inlet pipe 4 and an ammonia recovery pipe 5 are respectively arranged at the top and bottom of the washing tank 2. A flare pipe 6 is arranged on the side wall of the washing tank 2. The end of the demineralized water inlet pipe 4 away from the washing tank 2 is connected to a... The demineralized water is stored in a storage tank. The storage tank can pump / gravity to deliver the demineralized water to the inner cavity of the washing tank 2. The demineralized water entering the inner cavity of the washing tank 2 will come into contact with the gaseous ammonia. Taking advantage of the fact that ammonia is easily soluble in water, the ammonia in the gaseous ammonia will quickly dissolve in the demineralized water to form ammonia water. The ammonia water will accumulate at the bottom of the inner cavity of the washing tank 2 under the action of gravity and will finally be discharged through the ammonia water recovery pipe 5. This achieves the removal and recovery of ammonia from the gaseous ammonia. The remaining insoluble waste gas from the gaseous ammonia will be discharged and burned through the flare pipe 6. Not only is ammonia water obtained through recovery, which improves economic efficiency, but the combustion of gaseous ammonia is also reduced, which achieves the effect of emission reduction.

[0022] Since the small end of the converging tube 3 is radially tangent to the side wall of the washing tank 2, when the gaseous ammonia formed in the drain tank 1 enters through the large end of the converging tube 3, the converging tube 3 increases the flow velocity of the gaseous ammonia at the lower end through the Venturi effect, causing the gaseous ammonia to enter the inner cavity of the washing tank 2 at a higher flow velocity and form a rotating airflow inside. On the one hand, this allows the gaseous ammonia to be evenly distributed in the washing tank 2, ensuring that it is in full contact with the demineralized water supplied by the demineralized water inlet pipe 4, thus improving the utilization rate of the demineralized water. On the other hand, the rotating airflow formed by the gaseous ammonia will significantly prolong its flow path in the washing tank 2, increasing the contact time between the gaseous ammonia and the demineralized water, thereby improving the absorption efficiency of the demineralized water for the gaseous ammonia and thus increasing the ammonia recovery rate.

[0023] like Figure 1 As shown, the sewage tank 1 is positioned higher than the washing tank 2 to shorten the transport path of gaseous ammonia.

[0024] like Figure 2As shown, a jet pipe 21 is arranged in the inner cavity of the washing tank 2 near the converging tube 3. One outer end of the jet pipe 21 is sealed to the small opening end of the converging tube 3, and the inner end of the jet pipe 21 is radially tangent to the side wall of the washing tank 2 and communicates with the washing tank 2. In this way, the gaseous ammonia in the converging tube 3 will be transported to the washing tank 2 through the jet pipe 21 and form a rotating airflow. A spray pipe 22 is arranged in the inner cavity of the washing tank 2 near the demineralized water inlet pipe 4. The top end of the spray pipe 22 passes through the top end of the washing tank 2 and connects to the bottom port of the demineralized water inlet pipe 4. A demineralized water inlet control valve 41 is installed on the water pipe 4. When the demineralized water inlet control valve 41 is opened, the demineralized water inlet pipe 4 will transport the demineralized water inside to the spray pipe 22. The arrangement of the spray pipe 22 is the same as that of the jet pipe 21. The difference is that several through holes are opened at the bottom of the spray pipe 22 so that the demineralized water inside can be sprayed out evenly. In this way, the demineralized water will fall freely in the inner cavity of the washing tank 2 due to its own gravity, while the gaseous ammonia will rotate and rise in the inner cavity of the washing tank 2, ensuring that the demineralized water and gaseous ammonia are in full contact in the inner cavity of the washing tank 2, thereby improving the ammonia absorption effect of the demineralized water.

[0025] A shielded pump 7 is installed on the ammonia recovery pipe 5. The type and specifications of the shielded pump 7 are selected by those skilled in the art based on the flow rate of the ammonia recovery pipe 5.

[0026] As one embodiment of this application, such as Figures 1-3 As shown, the side wall of the sewage tank 1 is provided with a sewage inlet 11, and a guide hood 111 with an opening facing the direction is provided near the sewage inlet 11. The top and bottom of the sewage tank 1 are respectively provided with a gas outlet 12 and a discharge port 13. The gas outlet 12 is connected to the converging pipe 3. The sewage inlet 11 is used to receive the waste liquid of the ammonia cooler and transport it to the inner cavity of the sewage tank 1. When the waste liquid enters the inner cavity of the sewage tank 1, the guide hood 111 can make it form a vertically downward fluid, which on the one hand prevents the waste liquid from splashing, and on the other hand avoids it from affecting the gaseous ammonia formed in the sewage tank 1.

[0027] The side wall of the sewage tank 1 is also equipped with a steam inlet 14 and a nitrogen inlet 15, which are located at the bottom of the side wall of the sewage tank 1. The steam inlet 14 is used to supply steam into the inner cavity of the sewage tank 1 at a pressure of 0.5 MPa. The nitrogen inlet 15 is used to supply nitrogen into the inner cavity of the sewage tank 1. After the steam and nitrogen enter the inner cavity of the sewage tank 1, they will heat and strip the waste liquid to form gaseous ammonia. The gaseous ammonia will then be transported through the gas outlet 12 to the converging pipe 3, and then from the converging pipe 3 to the washing tank. The waste liquid is recycled and burned in 2. The remaining waste liquid in the sewage tank 1 is discharged through the drain port 13. A level gauge port 17 and a level switch port 18 are also provided at the bottom of the side wall of the sewage tank 1. A manhole 16 is provided in the middle of the side wall of the sewage tank 1. A pressure gauge port 19 is provided on the top of the sewage tank 1 near the gas outlet 12. The level gauge port 17, the level switch port 18, the manhole 16 and the pressure gauge port 19 are equipped with corresponding devices by those skilled in the art according to the function of the port, such as pressure gauges, level gauges or level switches.

[0028] The foregoing has provided a detailed description of one embodiment of this application, but the description is merely a preferred embodiment and should not be construed as limiting the scope of this application. All equivalent variations and modifications made within the scope of this application should still fall within the patent coverage of this application.

Claims

1. An ammonia recovery device for a sewage tank, characterized in that, It includes a converging tube (3) installed between the sewage tank (1) and the washing tank (2). The large end of the converging tube (3) is connected to the sewage tank (1) to receive gaseous ammonia, and the small end of the converging tube (3) is radially tangent to and connected to the side of the washing tank (2) to transport gaseous ammonia and make it form a rotating airflow in the washing tank (2).

2. The ammonia recovery device for a sewage tank according to claim 1, characterized in that, The top and bottom of the washing tank (2) are respectively provided with a demineralized water inlet pipe (4) and an ammonia water recovery pipe (5). The demineralized water inlet pipe (4) is used to transport the demineralized water to the inner cavity of the washing tank (2). The demineralized water comes into contact with the gaseous ammonia in the inner cavity of the washing tank (2) to form ammonia water, which is then recovered through the ammonia water recovery pipe (5).

3. An ammonia recovery device for a sewage tank according to claim 2, characterized in that, The side wall of the sewage tank (1) is provided with a sewage inlet (11), and the inner wall of the sewage tank (1) is provided with a downward-opening guide hood (111) near the sewage inlet (11).

4. An ammonia recovery device for a sewage tank according to any one of claims 1-3, characterized in that, A spray pipe (22) is arranged in the inner cavity of the washing tank (2) near the demineralized water inlet pipe (4), and the spray pipe (22) is connected to the demineralized water inlet pipe (4).

5. An ammonia recovery device for a sewage tank according to claim 4, characterized in that, The desalinated water inlet pipe (4) is equipped with a desalinated water inlet control valve (41).

6. An ammonia recovery device for a sewage tank according to claim 2, characterized in that, A shielded pump (7) is installed on the ammonia recovery pipe (5).

7. An ammonia recovery device for a sewage tank according to any one of claims 1-3, characterized in that, The sewage tank (1) is positioned higher than the washing tank (2) to shorten the transport path of ammonia gas.

8. An ammonia recovery device for a sewage tank according to any one of claims 1-3, characterized in that, The top and bottom of the sewage tank (1) are respectively provided with a gas outlet (12) and a discharge port (13), and the gas outlet (12) is connected to the converging pipe (3).

9. An ammonia recovery device for a sewage tank according to claim 8, characterized in that, The side wall of the sewage tank (1) is also provided with a steam inlet (14) and a nitrogen inlet (15).

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