Ammonia recovery and ammonia water preparation device and process based on citric acid cycle absorption

Abstract

This invention discloses an ammonia recovery and ammonia water preparation device based on citric acid recycling absorption in the field of ammonia recovery and treatment technology. The device includes a deammoniation tower and a stripping tower. The deammoniation tower receives an ammonia-containing reaction mixture and citric acid, reacting them to generate ammonium citrate, which is then fed into the stripping tower. The stripping tower processes the ammonium citrate to obtain citric acid and ammonia. One outlet of the stripping tower is connected to the deammoniation tower to recover citric acid, while the other outlet is recycled back into the stripping tower for spraying. A processing unit receives the ammonia discharged from the stripping tower, mixes it with water to form ammonia water, and then discharges it. This invention achieves the repeated recycling of citric acid, avoiding the generation of low-value ammonium salts, and also avoids the generation and treatment of saline wastewater. Excess ammonia in the ammonia-containing reaction mixture is used to form relatively higher-value ammonia water. Furthermore, this device effectively reduces steam consumption in the production process, resulting in low overall energy consumption and reducing the risk of hydrogen cyanide escape.

Description

Technical Field

[0001] This invention relates to the field of ammonia recovery and treatment, and specifically to an ammonia recovery and ammonia water preparation apparatus and process based on citric acid recycling absorption. Background Technology

[0002] Currently, in the production processes of hydrogen cyanide, the acrylonitrile by-product method, the natural gas ammonia oxidation method, and the methanol ammonia oxidation method all have the problem of excess ammonia as a reactant. Excess ammonia can easily lead to the risk of hydrogen cyanide polymerization, so it needs to be removed during the production process.

[0003] Common ammonia removal processes employ either water absorption or inorganic acid absorption. Water absorption has low efficiency and generates a large amount of dilute ammonia water that requires further treatment. While inorganic acid absorption is more efficient, it produces corresponding ammonium salt byproducts. These ammonium salts often require complex crystallization and drying processes before they can be sold as products, but the added value of these products is low. Furthermore, this process suffers from problems such as the inability to regenerate and recycle the absorbent, high consumption, and high production costs. Therefore, we propose an ammonia recovery and ammonia water preparation device and process based on citric acid recycling absorption. Summary of the Invention

[0004] The purpose of this invention is to provide an ammonia recovery and ammonia water preparation device and process based on citric acid cycle absorption, which solves the technical problems mentioned in the background art.

[0005] The present invention achieves the above objectives through the following technical solutions: An ammonia recovery and ammonia water preparation device based on citric acid cycle absorption includes an ammonia removal tower and a stripping tower; The ammonia removal tower is used to receive ammonia-containing reaction mixture gas and citric acid and react them to produce ammonium citrate, which is then fed into the stripping tower. The stripping tower is used to process ammonium citrate to obtain citric acid and ammonia. One outlet of the stripping tower is connected to the deammoniation tower to recover citric acid, and the other outlet is recycled back to the stripping tower for spraying. The processing unit is used to receive the ammonia discharged from the stripping tower, mix it with water to form ammonia water, and then discharge it.

[0006] A further improvement is that the reaction parameters of the deammoniation tower are: absorption temperature 40-85℃, pH value 3-7, and liquid-to-gas ratio 15-25:1.

[0007] A further improvement is that the deammoniation tower is equipped with an inlet pipe for the ammonia-containing reaction mixture, an inlet pipe for the citric acid, and a drain pipe for the ammonium citrate. The inlet pipe is connected to the deammoniation tower through a mixer, and the drain pipe is connected to a pump body. The output end of the pump body is connected to the mixer and the desorption tower through pipelines.

[0008] A further improvement is that the stripping tower includes a tower body, a nozzle assembly located at the top of the tower body, and a thermosiphon reboiler located at the bottom of the tower body. The thermosiphon reboiler is used to decompose ammonium citrate at high temperature to generate citric acid and ammonia. The stripping tower is connected to an ammonia discharge pipe for discharging ammonia. The outlet of the stripping tower is connected to a second pump body via a pipeline. The output end of the second pump body is connected to the deammoniation tower and the nozzle assembly via pipelines.

[0009] A further improvement is that the processing unit includes a Venturi tube connected to the ammonia discharge pipe, the outlet of the Venturi tube being connected to an ammonia absorption tank, the ammonia absorption tank being used to receive ammonia and water and mix them to form ammonia water, the ammonia absorption tank being connected to a pump body three, and the output end of the pump body three being connected to the liquid outlet pipe and the Venturi tube respectively through pipelines.

[0010] A further improvement is that symmetrically staggered flow guiding and mixing components are arranged on the inner walls of the tower body and below the nozzle components on both sides. The flow guiding and mixing components include a flow guiding plate with one end fixed to the inner wall of one side of the tower body, a gap between the other end of the flow guiding plate and the inner wall of the other side of the tower body, and a baffle at the top of the other end of the flow guiding plate. A flow diverting plate is provided at the top of the flow guiding plate. The top of the flow diverting plate is inclined, with the end away from the baffle above the other end. A flow collecting seat is inserted through the flow guiding plate at the end of the flow diverting plate facing the baffle. Several sets of water outlet pipes are evenly arranged at the bottom of the flow collecting seat. A liquid guide plate is inclinedly provided on one side of the inner wall of the tower body, located between the flow mixing component and the nozzle component. The liquid guide plate is used to guide the liquid sprayed from the nozzle component to the uppermost flow mixing component.

[0011] A further improvement is that a float plate for sealing the top of the water outlet pipe is movably installed inside the water collection seat, and the float plate is connected to the inner wall of the water collection seat through an elastic connector.

[0012] A further improvement is that an impeller is rotatably provided on the bottom wall of the guide plate and on one side of the water outlet pipe. The shaft of the impeller is provided with dispersing blades, and the impeller is used to drive the dispersing blades to disperse and break the liquid discharged from the water outlet pipe.

[0013] A further improvement is that a preheating component is provided on the pipeline connecting the pump body and the nozzle. The preheating component includes an insulation shell, and a heat-conducting column is rotatably arranged inside the insulation shell. A connecting blade is provided on the outer wall of the heat-conducting column. The connecting blade is driven by the liquid entering the insulation shell to rotate the heat-conducting column. A spiral channel is opened inside the heat-conducting column. Both ends of the heat-conducting column are provided with connectors that communicate with the spiral channel. Two sets of connectors pass through both ends of the insulation shell. One connector is connected to the ammonia discharge pipe, and the other connector is connected to the Venturi tube through a pipeline.

[0014] A process for ammonia recovery and ammonia water preparation based on citric acid cycle absorption, utilizing the aforementioned apparatus, includes the following steps: S1: After the ammonia-containing reaction mixture is introduced into the deammoniation tower, citric acid is then introduced. The two react in the deammoniation tower to produce ammonium citrate, which is then discharged to the stripping tower. S2: Ammonium citrate enters the stripping tower for processing to obtain citric acid and ammonia. Citric acid is discharged from the stripping tower outlet into the deammoniation tower to continue processing the ammonia-containing reaction mixture. It is also recycled back to the stripping tower from the stripping tower outlet for spraying. S3: The ammonia discharged from the stripping tower enters the treatment unit, where the ammonia is mixed with water to form ammonia water.

[0015] The beneficial effects of this invention are as follows: This invention enables the repeated recycling of citric acid, avoiding the generation of low-value ammonium salts. Simultaneously, the closed-loop circulation method allows citric acid to be recycled within the device without external discharge, avoiding the generation and treatment of saline wastewater. Excess ammonia in the ammonia-containing reaction mixture is converted into ammonia water, which has a relatively higher value, thus realizing the resource utilization of ammonia. Furthermore, this device effectively reduces steam consumption in the production process, resulting in lower overall energy consumption and reducing the risk of hydrogen cyanide escape. It boasts higher economic efficiency, safety, and environmental friendliness. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the device structure of the present invention; Figure 2 This is a schematic diagram of the analytical tower structure of the present invention; Figure 3 For the present invention Figure 2 The structural sectional view in the middle; Figure 4 This is a schematic diagram of the flow guiding and mixing component structure of the present invention; Figure 5 For the present invention Figure 4 Another perspective structural diagram; Figure 6 For the present invention Figure 3 Enlarged view of structure A in the image.

[0017] In the diagram: 1. Ammonia removal tower; 2. Inlet pipe; 3. Liquid inlet pipe; 4. Ammonia absorption tank; 5. Mixer; 6. Pump body one; 7. Desorption tower; 8. Thermosiphon reboiler; 9. Ammonia discharge pipe; 10. Pump body two; 11. Pump body three; 12. Liquid outlet pipe; 13. Nozzle component; 14. Liquid guide plate; 15. Flow guiding mixing component; 151. Flow guide plate; 152. Baffle; 153. Flow guide plate; 154. Flow collector; 155. Water outlet pipe; 156. Float plate; 157. Flexible connector; 158. Impeller component; 159. Dispersing blade; 16. Preheating component; 161. Insulation shell; 162. Heat conduction column; 163. Spiral channel; 164. Connecting blade; 17. Venturi tube. Detailed Implementation

[0018] The present application will now be described in further detail with reference to the accompanying drawings. It should be noted that the following specific embodiments are only used to further illustrate the present application and should not be construed as limiting the scope of protection of the present application. Those skilled in the art can make some non-essential improvements and adjustments to the present application based on the above application content. Example 1

[0019] Please see the appendix Figure 1 An ammonia recovery and ammonia water preparation device based on citric acid cycle absorption includes an ammonia removal tower 1 and an ammonia stripping tower 7. Both the ammonia removal tower 1 and the ammonia stripping tower 7 are conventional equipment in this field and will not be described in detail here. The ammonia removal tower 1 is used to receive the ammonia-containing reaction mixture gas and citric acid and react them to generate ammonium citrate, which is then fed into the stripping tower 7. In this embodiment, after the ammonia-containing reaction mixture gas enters the ammonia removal tower 1, it is absorbed by citric acid circulation. Through the ammonia removal tower 1, the two react fully under the conditions of absorption temperature 40-85℃, pH value 3-7, and liquid-to-gas ratio 15-25:1 to generate ammonium citrate. The ammonium citrate is then pumped into the stripping tower 7 for processing. The stripping tower 7 is used to process ammonium citrate to obtain citric acid and ammonia (the ammonia escapes from the top of the stripping tower 7). One outlet of the stripping tower 7 is connected to the deammoniation tower 1 to recover citric acid, thereby continuing to process the ammonia-containing reaction mixture. The other outlet is recycled back to the stripping tower 7 for spraying (the sprayed substance can be citric acid or ammonia citrate). The processing unit is used to receive the ammonia discharged from the stripping tower 7, mix it with water to form ammonia water, and then discharge it.

[0020] The above-mentioned device enables the repeated recycling of citric acid, avoiding the generation of low-value ammonium salts. Simultaneously, the closed-loop circulation method allows citric acid to be recycled within the device without external discharge, avoiding the generation and treatment of saline wastewater. Excess ammonia in the ammonia-containing reaction mixture is converted into ammonia water, which has a relatively higher value, thus realizing the resource utilization of ammonia. Furthermore, because the absorption process is controlled under weakly acidic conditions with a pH of 3-7, acidic impurities such as hydrogen cyanide are effectively captured by the solution in the deammoniation tower 1, reducing the risk of hydrogen cyanide escape. In summary, this device has higher economic efficiency, safety, and environmental friendliness.

[0021] Preferably, the deammoniation tower 1 in this embodiment is equipped with an inlet pipe 2 for the ammonia-containing reaction mixture, an inlet pipe 3 (with a regulating valve) for the citric acid, and a drain pipe for the ammonium citrate. The deammoniation tower 1 in this embodiment is also equipped with a pipe for discharging the deammoniation reaction gas. The inlet pipe 3 is connected to the deammoniation tower 1 via a mixer 5 (preferably a static pipeline mixer) (specifically connected to the liquid distributor in the deammoniation tower 1). The mixer 5 ensures uniform mixing of the citric acid. A pump body 6 (such as a washing pump) is installed on the drain pipe. The output end of the pump body 6 is connected to the mixer 5 and the desorption tower 7 via pipelines, as shown in the attached diagram. Figure 1 As shown, the pipeline connecting pump body 6 to mixer 5 is equipped with devices for measuring the pH value of the liquid (ammonia citrate), and the pipeline connecting pump body 6 to desorption tower 7 is equipped with a regulating valve. By switching control of pump body 6, some ammonium citrate can be sent back to mixer 5 to mix with fresh citric acid and then re-enter desorption tower 1 for circulation absorption, so as to adjust the pH value and concentration of the absorbent in desorption tower 1. Ammonium citrate can also be pumped into desorption tower 7 for treatment.

[0022] Please see the appendix Figure 1-3 Preferably, the desorption tower 7 in this embodiment includes a tower body, a nozzle 13 located at the top of the tower body, and a thermosiphon reboiler 8 located at the bottom of the tower body. The thermosiphon reboiler 8 is used to decompose ammonium citrate at high temperature to generate citric acid and ammonia. In this embodiment, the decomposition is carried out at a temperature of 100-140°C for 4-8 hours. The thermosiphon reboiler 8 utilizes the density difference between the liquid in the tower bottom and the heated gas-liquid mixture in the reboiler to drive the natural circulation of the liquid, achieving continuous heating and decomposition without the need for an additional power pump, which greatly reduces the energy consumption of this device. The top of the desorption tower 7 is connected to an ammonia discharge pipe 9 for discharging ammonia. The outlet of the desorption tower 7 is connected to a second pump body 10 (a circulation pump can be used) through a pipeline. The output end of the second pump body 10 is connected to the deammonia removal tower 1 and the nozzle 13 through pipelines, as shown in the attached figure. Figure 1 As shown, the pipeline connecting pump body 2 10 and deammoniation tower 1 has a regulating valve. Through the switching control of pump body 2 10, on the one hand, the processed citric acid can be sent back to deammoniation tower 1 for recycling, and on the other hand, some ammonium citrate or citric acid can be supplied to nozzle component 13 for re-spraying in the tower to increase the number of gas-liquid contact times and the desorption depth. In this embodiment, nozzle component 13 preferably adopts an atomizing nozzle structure to uniformly atomize the incoming liquid and spray it into the tower to fully contact the rising ammonia, preparing it for entering the thermosiphon reboiler 8 for processing.

[0023] Preferably, the processing unit in this embodiment includes a Venturi tube 17 (such as a Venturi nozzle) connected to the ammonia discharge pipe 9. The outlet of the Venturi tube 17 is connected to the ammonia absorption tank 4. The ammonia absorption tank 4 is used to receive ammonia and water and mix them to form ammonia water. In this embodiment, the ammonia absorption tank 4 is connected to a pipeline leading to the demineralized water. The ammonia absorption tank 4 is connected to a pump body 11 (which can be a water pump). The output end of the pump body 11 is connected to the outlet pipe 12 and the Venturi tube 17 through pipelines, as shown in the attached figure. Figure 1 As shown, the pipeline connecting the pump body 11 and the outlet pipe 12 has a regulating valve. By switching the pump body 11, on the one hand, ammonia water that has reached the target concentration can be sold or stored through the outlet pipe 12; on the other hand, ammonia water (or demineralized water) that has not reached the target concentration can be supplied to the Venturi tube 17. The water flow generates a local negative pressure through the throat of the Venturi tube 17, which actively draws the ammonia gas discharged from the desorption tower 7 into the water flow, realizing the first mixing and partial absorption of gas and water, and then entering the ammonia absorption tank 4. This process can complete the ammonia gas capture without additional power gas, further reducing the energy consumption of this device. In addition, the ammonia absorption tank 4 provides sufficient residence time and space for ammonia gas and water to further contact and transfer mass, and finally form uniform ammonia water. In this embodiment, the ammonia absorption tank 4 can preferably be equipped with baffles or baffle structures to extend the water flow path and prevent short-circuiting, thereby improving the absorption efficiency. Of course, it is not limited to this one, and will not be described in detail here.

[0024] A process for ammonia recovery and ammonia water preparation based on citric acid cycle absorption, utilizing the aforementioned apparatus, includes the following steps: S1: After the ammonia-containing reaction mixture is introduced into the deammoniation tower 1, citric acid is then introduced. The two react in the deammoniation tower 1 to generate ammonium citrate, which is then discharged to the stripping tower 7. S2: Ammonium citrate enters the stripping tower 7 for processing to obtain citric acid and ammonia. Citric acid is discharged from the outlet of stripping tower 7 into the deammoniation tower to continue processing the ammonia-containing reaction mixture. It is also recycled back to stripping tower 7 from the outlet of stripping tower 7 for spraying. S3: The ammonia discharged from the stripping tower 7 enters the treatment unit, where the ammonia is mixed with water to form ammonia water. Example 2

[0025] Please see the appendix Figure 2-5 Based on Example 1, in this example, flow guiding and mixing components 15 are symmetrically and staggeredly arranged on the inner walls of both sides of the tower body and below the nozzle component 13. The flow guiding and mixing component 15 includes a flow guide plate 151 fixed at one end to the inner wall of one side of the tower body. A gap is provided between the other end of the flow guide plate 151 and the inner wall of the other side of the tower body to form an ammonia gas rising channel. A baffle 152 is provided at the top of the other end of the flow guide plate 151 to intercept the liquid flowing along the flow guide plate 151 and reduce its dripping from the plate end. A guide plate 153 is provided at the top of the flow guide plate 151. The top of the guide plate 153 is inclined, and the end away from the baffle 152 is above the other end of the guide plate 153 to collect the dripping liquid and guide it towards the baffle 152. A collection seat 154 is inserted through the flow guide plate 151 at the end of the guide plate 153 facing the baffle 152. Several sets of water outlet pipes 155 are evenly provided at the bottom of the collection seat 154 along its width direction to allow the collected liquid to flow downward in the form of multiple thin streams. A liquid guide plate 14 is inclinedly provided on one side of the inner wall of the tower body, between the flow mixing component 15 and the nozzle component 13. The liquid guide plate 14 is used to guide the liquid sprayed by the nozzle component 13 to the uppermost flow mixing component 15. The lower end of the liquid guide plate 14 extends above the flow guide plate 153 of the uppermost flow mixing component 15 to accurately guide the liquid sprayed by the nozzle component 13 to the flow mixing component 15. The liquid sprayed from the nozzle 13 by the above-mentioned flow guide and mixing component 15 is collected, dispersed and guided to fall to form a uniformly distributed liquid curtain. At the same time, the rising gas flows upward in a tortuous manner between multiple sets of guide plates 151, repeatedly passing through the falling liquid curtain and making full contact with the liquid, thus extending the gas-liquid contact path, increasing the contact area and residence time, and enhancing the mass transfer effect.

[0026] Preferably, in this embodiment, a float plate 156 for sealing the top of the outlet pipe 155 is movably provided inside the collector 154. The float plate 156 is connected to the inner wall of the collector 154 via an elastic connector 157. In this embodiment, the elastic connector 157 includes a T-shaped guide rod with one end fixed to the inner wall of the collector 154 and movably passing through the float plate 156, and a spring sleeved on the outer wall of the T-shaped guide rod. The T-shaped guide rod is used to guide the up and down movement of the float plate 156 and prevent it from deviating. The spring is used to apply a downward preload to the float plate 156 so that it maintains the state of sealing the top of the outlet pipe 155 in the initial state. During operation, when the... After the liquid collected by the flow plate 153 enters the flow collector 154, the liquid level in the flow collector 154 gradually rises. Under the action of liquid buoyancy, the float plate 156 overcomes the spring force and floats upward, thereby opening the top of the water outlet pipe 155, allowing the liquid to drip downward through the water outlet pipe 155. This ensures that the water outlet pipe 155 is only opened after enough liquid has accumulated in the flow collector 154. When the appropriate liquid level has not been reached in the flow collector 154, the water outlet pipe 155 is in a closed state, reducing the probability of rising gas entering the water outlet pipe 155. This allows the gas to better zigzag upward through the gas channel between the guide plates 151 and fully contact the liquid curtain, ensuring the gas-liquid contact effect.

[0027] Preferably, in this embodiment, an impeller 158 is rotatably provided on the bottom wall of the guide plate 151 and on one side of the outlet pipe 155. The impeller 158 consists of an impeller and a shaft. The shaft of the impeller 158 is provided with a dispersing blade 159 (which can be a thin plate structure and inclined to increase the shearing effect on the droplets). The impeller 158 is used to drive the dispersing blade 159 to disperse and break the liquid discharged from the outlet pipe 155. Preferably, the bottom guide plate 151 may not be provided with an impeller 158 and a dispersing blade 159. During operation, the rising ammonia gas flows in the channel between the guide plates 151 and impacts the impeller 158, driving the impeller 158 to rotate, thereby driving the dispersing blade 159 to rotate. When the liquid flowing out of the outlet pipe 155 passes through the area where the dispersing blade 159 is located, the rotating dispersing blade 159 impacts and shears the liquid, breaking part of the liquid into droplets, increasing the gas-liquid contact surface area, and enhancing the gas-liquid contact effect. Example 3

[0028] Please see the appendix Figure 3 and Figure 6 Based on Example 1, in this example, a preheating element 16 is provided on the pipeline connecting the pump body 2 10 and the nozzle 13. The preheating component 16 includes an insulation shell 161, which is made of heat-insulating material or wrapped with an external heat-insulating layer to reduce heat loss. A heat-conducting column 162 is rotatably arranged inside the insulation shell 161. A connecting blade 164 is provided on the outer wall of the heat-conducting column 162. The connecting blade 164 is driven by the liquid (ammonium citrate or citric acid) entering the insulation shell 161 to rotate the heat-conducting column 162. Specifically, before the pump body 10 injects the liquid into the nozzle component 13, the liquid will enter the insulation shell 161 and impact the connecting blade 164, thereby causing the connecting blade 164 to drive the heat-conducting column 162 to rotate, and then discharge into the nozzle component 13. A spiral channel 163 is opened in the heat-conducting column 162. The spiral channel 163 is used to supply ammonia gas flow, and then exchange heat with the liquid flowing outside. Both ends of the heat-conducting column 162 are fixed with connectors that communicate with the spiral channel 163. The connectors are coaxial with the heat-conducting column 162. The two sets of connectors movably pass through both ends of the insulation shell 161. One connector can be connected to the ammonia discharge pipe 9 by a rotating connector, and the other connector can be connected to the pipeline by a rotating connector, and then connected to the Venturi tube 17 through the pipeline. The ammonia gas discharged from the ammonia discharge pipe 9 is introduced into the spiral channel 163 of the heat-conducting column 162 through the preheating component 16. During the flow in the spiral channel 163, its heat is transferred to the liquid flowing in the insulation shell 161 through the wall of the heat-conducting column 162, realizing heat exchange. The heat-exchanged ammonia gas is discharged to the venturi tube 17 for ammonia water preparation, while the preheated liquid enters the nozzle component 13 for spraying. The connecting blade 164 drives the heat-conducting column 162 to rotate, which can generate relative movement between the wall of the heat-conducting column 162 and the liquid, destroying the laminar boundary layer, enhancing the convective heat transfer effect, and making the circumferential heating of the heat-conducting column 162 more uniform, avoiding local overheating. By preheating the sprayed liquid through the preheating component 16, the steam consumption of the subsequent thermosiphon reboiler 8 is further reduced, and the thermal efficiency is improved.

[0029] The embodiments described above are merely examples of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the protection scope of the present invention.

Claims

1. An ammonia recovery and ammonia water preparation device based on citric acid cycle absorption, characterized in that, It includes a deammoniation tower (1) and a stripping tower (7); The ammonia removal tower (1) is used to receive the ammonia-containing reaction mixture gas and citric acid and react them to generate ammonium citrate, which is then fed into the stripping tower (7). The stripping tower (7) is used to process ammonium citrate to obtain citric acid and ammonia. One outlet of the stripping tower (7) is connected to the deammoniation tower (1) to recover citric acid, and the other outlet is recycled back to the stripping tower (7) for spraying. The processing unit is used to receive the ammonia discharged from the stripping tower (7) and mix it with water to form ammonia water before discharging it.

2. The apparatus according to claim 1, characterized in that, The reaction parameters of the deammoniation tower (1) are: absorption temperature 40-85℃, pH value 3-7, and liquid-to-gas ratio 15-25:

1.

3. The apparatus according to claim 1, characterized in that, The deammonia removal tower (1) is provided with an inlet pipe (2) for entering the ammonia-containing reaction mixture, an inlet pipe (3) for entering citric acid, and a drain pipe for discharging ammonium citrate. The inlet pipe (3) is connected to the deammonia removal tower (1) through a mixer (5), and the drain pipe is connected to a pump body (6). The output end of the pump body (6) is connected to the mixer (5) and the desorption tower (7) through pipelines.

4. The apparatus according to claim 1, characterized in that, The analysis tower (7) includes a tower body, a nozzle (13) located at the top of the tower body, and a thermosiphon reboiler (8) located at the bottom of the tower body. The thermosiphon reboiler (8) is used to decompose ammonium citrate at high temperature to generate citric acid and ammonia. The analysis tower (7) is connected to an ammonia discharge pipe (9) for discharging ammonia. The outlet of the analysis tower (7) is connected to a second pump body (10) through a pipeline. The output end of the second pump body (10) is connected to the deammoniation tower (1) and the nozzle (13) through pipelines respectively.

5. The apparatus according to claim 4, characterized in that, The processing unit includes a Venturi tube (17) connected to the ammonia discharge pipe (9). The outlet of the Venturi tube (17) is connected to the ammonia absorption tank (4). The ammonia absorption tank (4) is used to receive ammonia and water and mix them to form ammonia water. The ammonia absorption tank (4) is connected to a pump body three (11). The output end of the pump body three (11) is connected to the liquid outlet pipe (12) and the Venturi tube (17) through pipelines.

6. The apparatus according to claim 4, characterized in that, The inner walls of the tower body and below the nozzle (13) are symmetrically staggered with flow guiding and mixing components (15). The flow guiding and mixing component (15) includes a flow guiding plate (151) with one end fixed to the inner wall of one side of the tower body. There is a gap between the other end of the flow guiding plate (151) and the inner wall of the other side of the tower body. A baffle (152) is provided at the top of the other end of the flow guiding plate (151). A flow diverting plate (153) is provided at the top of the flow guiding plate (151). The top of the flow diverting plate (153) is inclined. One end of the flow diverting plate (153) away from the baffle (152) is above the other end. A flow collecting seat (154) is inserted through the flow guiding plate (151) at the end of the flow diverting plate (153) facing the baffle (152). Several sets of water outlet pipes (155) are evenly provided at the bottom of the flow collecting seat (154). A liquid guide plate (14) is inclinedly provided on one side of the inner wall of the tower body and located between the flow mixing component (15) and the nozzle component (13). The liquid guide plate (14) is used to guide the liquid sprayed by the nozzle component (13) to the uppermost flow mixing component (15).

7. The apparatus according to claim 6, characterized in that, The collector (154) is movably provided with a float plate (156) for sealing the top of the outlet pipe (155), and the float plate (156) is connected to the inner wall of the collector (154) through an elastic connector (157).

8. The apparatus according to claim 6, characterized in that, The bottom wall of the guide plate (151) is rotatably provided with an impeller (158) located on one side of the outlet pipe (155). The shaft of the impeller (158) is provided with a dispersing blade (159). The impeller (158) is used to drive the dispersing blade (159) to disperse and break the liquid discharged from the outlet pipe (155).

9. The apparatus according to claim 5, characterized in that, A preheating component (16) is provided on the pipeline connecting the pump body (10) and the nozzle component (13). The preheating component (16) includes an insulation shell (161). A heat-conducting column (162) is rotatably arranged inside the insulation shell (161). A connecting blade (164) is provided on the outer wall of the heat-conducting column (162). The connecting blade (164) is driven by the liquid entering the insulation shell (161) to rotate the heat-conducting column (162). A spiral channel (163) is opened inside the heat-conducting column (162). Both ends of the heat-conducting column (162) are provided with connectors that communicate with the spiral channel (163). The two sets of connectors pass through both ends of the insulation shell (161). One connector is connected to the ammonia discharge pipe (9), and the other connector is connected to the Venturi tube (17) through a pipeline.

10. A process for ammonia recovery and ammonia water preparation based on citric acid cycle absorption, utilizing the apparatus as described in any one of claims 1-9, characterized in that, Includes the following steps: S1: After the ammonia-containing reaction mixture is introduced into the deammoniation tower (1), citric acid is then introduced. The two react in the deammoniation tower (1) to generate ammonium citrate, which is then discharged to the stripping tower (7). S2: Ammonium citrate enters the stripping tower (7) for processing to obtain citric acid and ammonia. Citric acid is discharged from the outlet of the stripping tower (7) into the deammoniation tower to continue processing the ammonia-containing reaction mixture gas. It is also recycled back to the stripping tower (7) from the outlet of the stripping tower (7) for spraying. S3: The ammonia discharged from the stripping tower (7) enters the treatment unit, where the ammonia is mixed with water to form ammonia water.

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