MVR falling film ammonia evaporation device

Abstract

The utility model discloses a kind of MVR falling film ammonia evaporation device, it is related to wastewater ammonia removal technical field, it includes ammonia evaporation front liquid pump, ammonia evaporation front liquid tank, gas-liquid separator, steam compressor, ammonia evaporation front liquid pump is connected in ammonia evaporation front liquid tank by connecting pipe, and ammonia evaporation front liquid tank is connected with gas-liquid separator by first pipeline, ammonia evaporation front liquid pump and gas-liquid separator and steam compressor are all connected in falling film ammonia evaporation tower assembly;Falling film ammonia evaporation tower assembly includes disc distributor, heat exchange pipe and tower body, and the bottom of disc distributor is connected with several groups of heat exchange pipe, disc distributor evenly distributes ammonia evaporation front liquid to every heat exchange pipe upper end, and heat exchange pipe inside is equipped with falling film passage, ammonia evaporation front liquid forms film-like flow along heat exchange pipe inner wall under the action of gravity, and steam compressor is contacted with tower body and heat exchange pipe after temperature and pressure increasing to ammonia-containing steam, and heat exchange with ammonia evaporation front liquid in heat exchange pipe.This MVR falling film ammonia evaporation device significantly reduces consumed electric energy and operating cost.

Description

Technical Field

[0001] This utility model relates to the field of wastewater ammonia removal technology, and in particular to an MVR falling film ammonia stripping device. Background Technology

[0002] Ammonia stripping is a process that removes ammonia nitrogen from wastewater through physical or chemical methods. Its main purpose is to remove ammonia nitrogen from wastewater, reduce environmental pollution, and recover ammonia water for reuse. The current mainstream ammonia stripping technology mainly uses steam to pass into the ammonia stripping tower to complete the mass transfer process with the wastewater. However, traditional MVR process ammonia stripping units require the consumption of live steam (such as boiler steam), resulting in high energy consumption and significant operating costs. At the same time, energy utilization is not sufficient. Furthermore, since the liquid to be treated before ammonia stripping may contain impurities, long-term operation can easily lead to blockage of heat exchange tubes, affecting treatment efficiency. Utility Model Content

[0003] The present invention proposes an MVR falling film ammonia stripping device, which solves the problems of high energy consumption and heat exchange tube blockage in existing MVR falling film ammonia stripping devices.

[0004] To achieve the above objectives, the present invention adopts the following technical solution:

[0005] A falling film ammonia stripping device includes an ammonia stripping pre-liquid pump, an ammonia stripping pre-liquid tank, a gas-liquid separator, and a steam compressor. The ammonia stripping pre-liquid pump is connected to the ammonia stripping pre-liquid tank via a connecting pipe, and the ammonia stripping pre-liquid tank is connected to the gas-liquid separator via a first pipe. The ammonia stripping pre-liquid pump, the gas-liquid separator, and the steam compressor are all connected to the falling film ammonia stripping tower assembly.

[0006] The falling film ammonia stripping tower assembly includes a disc distributor, heat exchange tubes, and a tower body. The bottom of the disc distributor is connected to several sets of heat exchange tubes. The disc distributor evenly distributes the pre-absorption liquid to the upper end of each heat exchange tube. Each heat exchange tube is provided with a falling film channel. Under the action of gravity, the pre-absorption liquid forms a thin film and flows along the inner wall of the heat exchange tube. The steam compressor heats and pressurizes the ammonia-containing vapor and discharges it into the tower body to contact the heat exchange tubes and exchange heat with the pre-absorption liquid in the heat exchange tubes.

[0007] Preferably, a tower body is provided on the outside of the heat exchange tube, and a steam compressor is provided on the outside of the tower body. The steam compressor is connected to the inside of the tower body through a compression pipe.

[0008] Preferably, a drain pipe is provided on the outside of the heat exchange tube inside the tower body, and an ammonia tank is provided on the outside of the tower body. The drain pipe is connected to the ammonia tank, and an ammonia pump is provided on the outside of the ammonia tank.

[0009] Preferably, the disc distributor is provided with an upper end cap on its outer side, and the upper end cap is connected to the tower body by a first bolt. The side of the disc distributor is provided with a first connection port located outside the upper end cap, and the gas-liquid separator is connected to the first connection port through a pipe. The top of the upper end cap is provided with a second connection port, and the ammonia pre-disinfection liquid pump is connected to the second connection port.

[0010] Preferably, the bottom of the tower body is provided with a lower end cap, and the lower end cap is connected to the bottom of the tower body by a second bolt, and a support base is provided at the bottom of the lower end cap.

[0011] Preferably, a water outlet pipe is provided on the outside of the lower end cap, and one end of the water outlet pipe is connected to the heat exchange pipe inside the tower body through the lower end cap, while an ammonia water post-liquid pump is provided on the outside of the other end of the water outlet pipe.

[0012] Preferably, the gas-liquid separator is connected to the steam compressor via a second pipe.

[0013] Compared with the prior art, the beneficial effects of this utility model are:

[0014] 1. This MVR falling film ammonia stripping unit uses a steam compressor to compress and heat ammonia-containing steam, which then exchanges heat with the pre-stripping liquid in the heat exchange tubes. After heat exchange, part of the ammonia-containing steam enters the gas-liquid separator through the first connection port and the connecting pipe. The gas-liquid separator then re-enters the steam compressor through the second pipe, thus achieving efficient recovery and reuse of the latent heat of the steam. This avoids the large consumption of cooling water in the traditional process. According to statistics, the improved process mainly consumes electricity, and its energy cost is only 1 / 3 to 1 / 4 of that of the traditional ammonia stripping tower. This improvement not only reduces the economic burden on enterprises but also conforms to the current green and sustainable development concept.

[0015] 2. The bottom of the disc distributor is connected to several sets of heat exchange tubes. After the ammonia pre-disinfection liquid is pumped into the top of the tower by the ammonia pre-disinfection liquid pump, it is evenly distributed to the upper end of each heat exchange tube through the disc distributor. It flows down naturally along the tube wall to form a thin film. During this process, the thin film exchanges heat with the steam outside the tube wall, completing the mass transfer. Ammonia evaporates from the liquid. This design not only improves the mass transfer efficiency, but also promotes the effective utilization of heat.

[0016] 3. The upper and lower end caps are connected to the top and bottom of the tower body by the first bolt and the second bolt, respectively. The detachable design facilitates the replacement of internal components of the tower body. At the same time, it is convenient to regularly clean the heat exchange tubes with chemical cleaning or high-pressure water gun to prevent blockage. Severely damaged heat exchange tubes can also be directly replaced, ensuring the quality of film formation on the inner wall of the heat exchange tubes and improving the ammonia stripping efficiency. Attached Figure Description

[0017] Figure 1 This is a traditional process flow diagram.

[0018] Figure 2 This is a flowchart illustrating the process of this utility model.

[0019] Figure 3 This is a schematic diagram of the falling film ammonia stripping tower component of this utility model.

[0020] Figure 4 This is a schematic diagram of the falling film ammonia stripping tower assembly from another perspective of this utility model.

[0021] Figure 5 This is a schematic diagram of the exploded structure of the falling film ammonia stripping tower component of this utility model.

[0022] The following are the labels in the diagram: 1. Ammonia pre-dispensing liquid pump; 2. Ammonia pre-dispensing liquid tank; 3. Gas-liquid separator; 4. Steam compressor; 5. Connecting pipe; 7. Disc distributor; 8. Heat exchange tube; 10. Tower body; 11. Through pipe; 12. Compression pipe; 13. Upper end cap; 14. First bolt; 16. First connection port; 17. Second connection port; 18. Lower end cap; 19. Second bolt; 20. Support base; 21. Drain pipe; 22. Ammonia tank; 23. Ammonia pump; 24. Water outlet pipe; 25. Ammonia post-dispensing liquid pump; 26. First pipeline; 27. Second pipeline. Detailed Implementation

[0023] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present utility model. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments.

[0024] Reference Figure 1 As shown, in the traditional process, the pre-ammonia liquid is pumped into the ammonia stripping tower by the pre-ammonia liquid pump. The pre-ammonia liquid completes the mass transfer process with the steam in the ammonia stripping tower. The ammonia-containing steam enters the condenser and exchanges heat with the circulating cooling water before condensing into ammonia water. The post-ammonia liquid is pumped out of the system by the post-ammonia liquid pump.

[0025] This invention further improves and optimizes the traditional process: by using a compressor to mechanically recompress the ammonia-containing vapor, the latent heat of the vapor is recovered; compared with the traditional process that requires cooling water for heat exchange, energy costs are significantly reduced. Details are as follows:

[0026] Reference Figure 2 , Figure 4This utility model provides a technical solution: an MVR falling film ammonia stripping device, comprising an ammonia stripping pre-liquid pump 1, an ammonia stripping pre-liquid tank 2, a gas-liquid separator 3, and a steam compressor 4. The ammonia stripping pre-liquid pump 1 is connected to the ammonia stripping pre-liquid tank 2 via a connecting pipe 5, and the ammonia stripping pre-liquid tank 2 is connected to the gas-liquid separator 3 via a first pipe 26. The ammonia stripping pre-liquid pump 1, the gas-liquid separator 3, and the steam compressor 4 are all connected to the falling film ammonia stripping tower assembly. The falling film ammonia stripping tower assembly includes a disc distributor 7, heat exchange tubes 8, and a tower body 10, and the bottom of the disc distributor 7 is connected to several sets of heat exchange tubes 8. The heat exchange tube 8 is the core heat and mass transfer element of the falling film ammonia stripping tower assembly. The number and height of the heat exchange tube 8 need to be determined through strict mass transfer process calculations to ensure optimal heat transfer efficiency and ammonia recovery rate. The disc distributor 7 evenly distributes the pre-stripping liquid to the upper end of each heat exchange tube 8, and each heat exchange tube 8 is equipped with a falling film channel. Under the action of gravity, the pre-stripping liquid forms a thin film and flows along the inner wall of the heat exchange tube 8. The steam compressor 4 heats and pressurizes the ammonia-containing vapor and discharges it into the tower body 10 to contact the heat exchange tube 8 and exchange heat with the pre-stripping liquid in the heat exchange tube 8.

[0027] Reference Figure 2 A tower body 10 is installed outside the heat exchange tube 8. The tower body 10 is the main structure of the falling film ammonia stripping tower. It is usually made of corrosion-resistant materials to withstand high temperature, high pressure and corrosive media. A steam compressor 4 is installed outside the tower body 10. The steam compressor 4 is connected to the inside of the tower body 10 through a compression pipe 12. A drain pipe 21 is installed outside the heat exchange tube 8 inside the tower body 10. An ammonia tank 22 is installed outside the tower body 10. The drain pipe 21 is connected to the ammonia tank 22. An ammonia pump 23 is installed outside the ammonia tank 22.

[0028] Reference Figure 4 , Figure 5 The disc distributor 7 has an upper end cap 13 on its outer side, and the upper end cap 13 is connected to the tower body 10 by a first bolt 14. The disc distributor 7 has a first connection port 16 on its side outside the upper end cap 13, and the gas-liquid separator 3 is connected to the first connection port 16 through a pipe 11. The upper end cap 13 has a second connection port 17 on its top, and the ammonia pre-vaporization liquid pump 1 is connected to the second connection port 17. The tower body 10 has a lower end cap 18 at its bottom, and the lower end cap 18 is connected to the bottom of the tower body 10 by a second bolt 19. The lower end cap 18 has a support base 20 at its bottom, and a water outlet pipe 24 is provided on the outer side of the lower end cap 18. One end of the water outlet pipe 24 is connected to the heat exchange pipe 8 inside the tower body 10 through the lower end cap 18, and the other end of the water outlet pipe 24 is provided to the outer side of the ammonia post-vaporization liquid pump 25. The gas-liquid separator 3 is connected to the steam compressor 4 through a second pipe 27.

[0029] In practical implementation, when using an MVR falling film ammonia stripping device, the ammonia stripping pre-liquid is pumped into the falling film ammonia stripping tower assembly by the ammonia stripping pre-liquid pump 1. The ammonia stripping pre-liquid first enters the disc distributor 7 through the second connection port 17. Because the bottom of the disc distributor 7 is connected to several sets of heat exchange tubes 8, and the disc distributor 7 consists of an inlet, a disc surface, and multiple outlets, the liquid flows along the surface of the disc after entering from the inlet and is evenly distributed through the outlets (not shown in the figure), thereby achieving the even distribution of the ammonia stripping pre-liquid entering the tower body 10 to each section of the tower. At the upper end of a heat exchange tube 8, a good distribution effect is key to ensuring the efficient operation of the falling film ammonia stripping process. Then, because each heat exchange tube 8 has falling film channels, the liquid before ammonia stripping flows in a thin film along the inner wall of the heat exchange tube 8 under gravity. Simultaneously, the steam compressor 4 is started, heating and pressurizing the ammonia-containing vapor and sending it back to the tower body 10 through the compression pipe 12. The heated and pressurized ammonia-containing vapor enters the falling film ammonia stripping tower assembly and exchanges heat with the liquid before ammonia stripping in the heat exchange tube 8. Then, some of the ammonia-containing vapor rises from the bottom. The liquid, carried by the vapor, is introduced into the gas-liquid separator 3 through the first connection port 16 and the through pipe 11. The vapor undergoes gas-liquid separation in the gas-liquid separator 3. The separated liquid flows by gravity into the pre-ammonia stripping liquid tank 2 through the first pipe 26. The separated ammonia-containing vapor then re-enters the steam compressor 4 through the second pipe 27 for heating and pressurization. The heated and pressurized ammonia-containing vapor then enters the falling film ammonia stripping tower assembly to exchange heat with the pre-ammonia stripping liquid in the heat exchange tube 8, thereby achieving efficient recovery and reuse of the latent heat of the steam. Following this, the heat exchange... The remaining ammonia vapor condenses into ammonia water, which collects at the bottom of the tower body 10. The ammonia water inside the heat exchange tube 8 flows by gravity into the lower head 18. Then, the ammonia water pump 25 and the ammonia water pump 23 are started. The ammonia water inside the lower head 18 is pumped out to the outside of the falling film ammonia stripping tower assembly by the ammonia water pump 25. The ammonia water pump 23 pumps the ammonia water collected at the bottom of the tower body 10 into the ammonia water tank 22. Through the above operations, the latent heat of steam is efficiently recovered and reused, and the energy cost is only 1 / 3 to 1 / 4 of that of the traditional ammonia stripping tower.

[0030] In addition, when the heat exchange tube 8 becomes clogged, the first bolt 14 and the second bolt 19 can be unscrewed to remove the upper end cap 13 and the lower end cap 18 from the top and bottom of the tower body 10. The inside of the heat exchange tube 8 can be cleaned by chemical cleaning or high-pressure water gun cleaning to prevent blockage. At the same time, the severely damaged heat exchange tube 8 can also be directly replaced. Then, the upper end cap 13 and the lower end cap 18 are fixed to the top and bottom of the tower body 10 by the first bolt 14 and the second bolt 19. Through the above operations, the maintenance of the MVR falling film ammonia stripping unit is more convenient, the maintenance cost is reduced, and the ammonia stripping efficiency is improved.

[0031] The above are merely preferred embodiments of this utility model, but the scope of protection of this utility model is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in this utility model, based on the technical solution and inventive concept of this utility model, should be included within the scope of protection of this utility model.

Claims

1. An MVR falling film ammonia stripping device, characterized in that, The ammonia stripping pre-liquid pump (1), ammonia stripping pre-liquid tank (2), gas-liquid separator (3), and steam compressor (4) are included. The ammonia stripping pre-liquid pump (1) is connected to the ammonia stripping pre-liquid tank (2) through a connecting pipe (5), and the ammonia stripping pre-liquid tank (2) is connected to the gas-liquid separator (3) through a first pipe (26). The ammonia stripping pre-liquid pump (1), the gas-liquid separator (3), and the steam compressor (4) are all connected to the falling film ammonia stripping tower assembly. The falling film ammonia stripping tower assembly includes a disc distributor (7), heat exchange tubes (8), and a tower body (10). The bottom of the disc distributor (7) is connected to several sets of heat exchange tubes (8). The disc distributor (7) distributes the ammonia stripping liquid evenly to the upper end of each heat exchange tube (8). The heat exchange tubes (8) are provided with falling film channels inside. The ammonia stripping liquid forms a thin film and flows along the inner wall of the heat exchange tubes (8) under the action of gravity. The steam compressor (4) heats and pressurizes the ammonia-containing vapor and discharges it into the tower body (10) to contact the heat exchange tubes (8) and exchange heat with the ammonia stripping liquid in the heat exchange tubes (8).

2. The MVR falling film ammonia stripping device according to claim 1, characterized in that, A tower body (10) is provided on the outside of the heat exchange tube (8), and a steam compressor (4) is provided on the outside of the tower body (10). The steam compressor (4) is connected to the inside of the tower body (10) through a compression pipe (12).

3. The MVR falling film ammonia stripping device according to claim 2, characterized in that, A drain pipe (21) is provided on the outside of the heat exchange tube (8) inside the tower body (10), and an ammonia tank (22) is provided on the outside of the tower body (10). The drain pipe (21) is connected to the ammonia tank (22), and an ammonia pump (23) is provided on the outside of the ammonia tank (22).

4. The MVR falling film ammonia stripping device according to claim 1, characterized in that, The disc distributor (7) is provided with an upper end cap (13) on its outer side, and the upper end cap (13) is connected to the tower body (10) by a first bolt (14). The disc distributor (7) is provided with a first connection port (16) on its side outside the upper end cap (13), and the gas-liquid separator (3) is connected to the first connection port (16) through a pipe (11). The upper end cap (13) is provided with a second connection port (17) on its top, and the ammonia pre-steaming liquid pump (1) is connected to the second connection port (17).

5. The MVR falling film ammonia stripping device according to claim 1, characterized in that, The bottom of the tower body (10) is provided with a lower end cap (18), and the lower end cap (18) is connected to the bottom of the tower body (10) by a second bolt (19). The bottom of the lower end cap (18) is provided with a support base (20).

6. The MVR falling film ammonia stripping device according to claim 5, characterized in that, A water outlet pipe (24) is provided on the outside of the lower end cap (18), and one end of the water outlet pipe (24) is connected to the heat exchange pipe (8) inside the tower body (10) through the lower end cap (18), and an ammonia water post-liquid pump (25) is provided on the outside of the other end of the water outlet pipe (24).

7. The MVR falling film ammonia stripping device according to claim 1, characterized in that, The gas-liquid separator (3) is connected to the steam compressor (4) via a second pipe (27).

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