A device and method for combined treatment of sulfur-containing tail gas and ammonia-nitrogen wastewater

Abstract

This invention relates to the field of wastewater and waste gas treatment technology, specifically to a device and method for the combined treatment of sulfur-containing tail gas and ammonia nitrogen wastewater. The combined treatment device includes a sulfur-containing tail gas treatment tower, an ammonia nitrogen wastewater treatment tower, and an ammonia gas collection tower. The gas phase exit line of the sulfur-containing tail gas treatment tower is connected to the inlet of the ammonia nitrogen wastewater treatment tower via a tail gas conveying pipeline. The top gas phase exit line of the ammonia nitrogen wastewater treatment tower is connected to the ammonia gas collection tower via an ammonia-rich tail gas conveying pipeline. The liquid phase exit line of the ammonia gas collection tower is connected to the sulfur-containing tail gas treatment tower via an ammonia water conveying pipeline. This invention combines the treatment of Claus sulfur recovery tail gas with the converted high-ammonia nitrogen wastewater, achieving the combined treatment of sulfur-containing tail gas and ammonia nitrogen wastewater with relatively low capital investment.

Description

Technical Field

[0001] This invention relates to the field of integrated wastewater and waste gas treatment technology, specifically to a device and method for the combined treatment of sulfur-containing tail gas and ammonia nitrogen wastewater. Background Technology

[0002] The background technology of this invention is intended to point out the background of the development of this invention, and does not mean that the background technology is admitted to be prior art of this invention.

[0003] In coal chemical production, after sulfur recovery treatment, the tail gas of Claus acid gas contains SO2 and sulfur dust. After the sulfur is washed away by the scrubbing tower, the tail gas is sent to the boiler for incineration. The sulfur dust is easily adsorbed on the pipe wall and clogs the pipe and scrubbing tower, causing the scrubbing tower plate to be blocked and the tower wall to be corroded many times. Moreover, because the tail gas contains SO2, it is highly corrosive and has repeatedly caused corrosion of the tail gas pipe. The sulfur recovery wastewater treatment process is long, consumes a lot of resources, and is difficult to treat. It is necessary to treat the sulfur-containing tail gas to reduce sulfur dust.

[0004] After the converted gas is washed with water, the high ammonia nitrogen wastewater enters the stripping tower and is stripped in a counter-current manner with low-pressure steam. The high ammonia nitrogen gas phase is then vented through the flare, causing some environmental pollution. At the same time, it causes water corrosion in the flare gas pipeline, resulting in a large amount of liquid in the flare gas, which affects the normal operation of the flare system. The ammonia nitrogen-containing liquid phase after stripping is sent to the wastewater treatment plant, which has a serious odor on site and fluctuates ammonia nitrogen levels, making wastewater treatment difficult. It is necessary to solve the pollution problem of high ammonia nitrogen wastewater. Summary of the Invention

[0005] To address the aforementioned problems, this invention provides a device and method for the combined treatment of sulfur-containing tail gas and ammonia nitrogen wastewater, which combines Claus sulfur recovery tail gas with high ammonia nitrogen wastewater after conversion, achieving the combined treatment of sulfur-containing tail gas and ammonia nitrogen wastewater with relatively low capital investment.

[0006] The technical solution adopted in this application to address this technical problem is as follows:

[0007] A combined treatment device for sulfur-containing tail gas and ammonia nitrogen wastewater includes a sulfur-containing tail gas treatment tower, an ammonia nitrogen wastewater treatment tower, and an ammonia gas collection tower.

[0008] The gas phase output line of the sulfur-containing tail gas treatment tower is connected to the inlet of the ammonia nitrogen wastewater treatment tower via a tail gas conveying pipeline. The top gas phase output line of the ammonia nitrogen wastewater treatment tower is connected to the ammonia collection tower via an ammonia-rich tail gas conveying pipeline. The liquid phase output line of the ammonia collection tower is connected to the sulfur-containing tail gas treatment tower via an ammonia water conveying pipeline.

[0009] Through combined treatment, the ammonia nitrogen in the ammonia nitrogen wastewater can help remove sulfur particles from the sulfur-containing tail gas, reducing clogging problems in the treatment of sulfur-containing tail gas and reducing environmental pollution. The temperature in the sulfur-containing tail gas can raise the gas temperature, which can strip the ammonia nitrogen wastewater and reduce the amount of superheated steam used. Thus, the combined treatment reduces the various problems that would occur with individual treatment.

[0010] Furthermore, the sulfur-containing tail gas treatment tower is a scrubbing tower for Claus sulfur recovery tail gas; the ammonia nitrogen wastewater treatment tower is a stripping tower in the coal chemical process; and the ammonia collection tower is an absorption tower.

[0011] The only new equipment in this invention is the ammonia collection tower. The combined treatment device requires less investment, has a high equipment utilization rate, and improves the economic benefits of enterprises.

[0012] Furthermore, the top of the scrubbing tower is used to receive sulfur-containing tail gas and ammonia water transported by the absorption tower, the middle of the scrubbing tower is equipped with an alkali spraying device, and the lower part of the scrubbing tower is equipped with a scrubbing liquid discharge pipeline and a tail gas transport pipeline.

[0013] The lower part of the stripping tower is connected to the tail gas conveying pipeline, the bottom of the stripping tower is connected to the stripping liquid discharge pipeline, the upper part of the stripping tower is connected to the ammonia nitrogen wastewater pipeline and is equipped with an ammonia nitrogen wastewater spraying device, and the top of the stripping tower is connected to the ammonia-rich tail gas conveying pipeline.

[0014] The lower part of the absorption tower is connected to the ammonia-rich tail gas conveying pipeline, and the lower end of the absorption tower is connected to the ammonia water conveying pipeline to convey ammonia water to the top of the scrubbing tower. A spray absorption device is installed inside the absorption tower, and the top of the absorption tower is connected to the boiler via a waste gas pipeline.

[0015] A branch pipe is provided on the gas stripping liquid discharge pipeline, and the branch pipe is connected to the spray absorption device at the top of the absorption tower.

[0016] The pipeline connections of the three treatment towers were disclosed in detail. This connection reduces the amount of pollutants discharged from the joint treatment and enables the reasonable utilization of the heat from the exhaust gas.

[0017] Furthermore, the washing liquid discharge pipeline is connected to the ammonia nitrogen wastewater pipeline, and a pipeline mixer is installed on the ammonia nitrogen wastewater pipeline.

[0018] Incorporating the washing liquid into the ammonia nitrogen wastewater pipeline can not only further treat sulfur particles, but also raise the temperature of the fluid in the ammonia nitrogen wastewater pipeline, which is beneficial for stripping.

[0019] Furthermore, the washing tower is equipped with a washing liquid circulation spray device inside the tower body. The washing liquid circulation spray device is located above the alkali addition spray device. The lower end of the washing tower is also connected to a washing liquid circulation pipeline, which is connected to the washing liquid circulation spray device.

[0020] Circulating spraying helps to provide a better pH environment for exhaust gas treatment, which enables the rapid reduction of sulfur particles.

[0021] Furthermore, the bottom of the absorption tower is also connected to a concentrated liquid circulation pipeline, and a concentrated liquid circulation spraying device is provided inside the absorption tower, which is connected to the concentrated liquid circulation pipeline.

[0022] Circulating spraying helps to increase the concentration of ammonia water.

[0023] Furthermore, a heat exchanger is provided on the stripping liquid discharge pipeline, wherein the hot fluid of the heat exchanger is the stripping tower bottom liquid, and the cold fluid is ammonia nitrogen wastewater from the ammonia nitrogen wastewater pipeline.

[0024] Make full use of the temperature of the wastewater that will be discharged.

[0025] Furthermore, a pH meter is installed on the ammonia nitrogen wastewater pipeline near the stripping tower.

[0026] A method for the combined treatment of sulfur-containing tail gas and ammonia nitrogen wastewater includes the following steps:

[0027] Step S1: Ammonia nitrogen wastewater is stripped by a stripping tower to obtain stripping wastewater and stripping gas, of which the stripping wastewater is discharged externally;

[0028] Step S2: The stripping gas obtained in step S1 is absorbed and concentrated to obtain ammonia water;

[0029] Step S3: The ammonia water obtained in step S2 is used to contact with sulfur-containing tail gas to obtain tail gas and washing liquid. The washing liquid is added to the ammonia nitrogen wastewater in step S1, and the tail gas is used to strip the ammonia nitrogen wastewater in step S1.

[0030] Furthermore, the ammonia nitrogen wastewater undergoes heat exchange with the bottom liquid from the stripping tower before being discharged into the stripping tower.

[0031] Beneficial effects

[0032] 1. This invention combines the treatment of Claus sulfur recovery tail gas with the high ammonia nitrogen wastewater after conversion, which not only reduces the problems of blockage of the Claus sulfur recovery tail gas scrubbing tower plates and corrosion of the tower wall, but also reduces the consumption of ammonia nitrogen wastewater treatment and reduces the environmental pollution caused by the flare release of high ammonia nitrogen gas phase.

[0033] 2. The scrubbing tower of the present invention is a Claus sulfur recovery tail gas scrubbing tower, and the stripping tower is a stripping tower in the coal chemical process. Only the absorption tower is a new piece of equipment. The whole set of equipment has few new equipment, high treatment efficiency, and achieves the joint treatment of sulfur-containing tail gas and ammonia nitrogen wastewater with less capital investment, and reduces various problems when sulfur tail gas and ammonia nitrogen wastewater are treated separately.

[0034] 3. In the joint treatment of Claus sulfur recovery tail gas and high ammonia nitrogen wastewater after conversion, the present invention utilizes the higher temperature of Claus sulfur recovery tail gas to treat ammonia nitrogen wastewater, and utilizes the ammonia in ammonia nitrogen wastewater to treat SO2 and sulfur in Claus sulfur recovery tail gas. The process has low consumption, low emission pollution, and significantly reduces the difficulty and cost of subsequent treatment of emissions. Attached Figure Description

[0035] Figure 1 This is a process flow diagram of the present invention;

[0036] Figure 2 This refers to the sulfur recovery device section in the process flow diagram of this invention;

[0037] Figure 3 This is the transformation device part in the process flow diagram of the present invention;

[0038] Figure 4 This is a newly added equipment component in the process flow diagram of this invention.

[0039] The attached diagram is labeled as follows: 1. Scrubber; 2. Stripping tower; 3. Absorption tower; 4. Alkali regulating valve; 5. Scrubber discharge pipeline; 6. Scrubber circulation pipeline; 7. Tail gas conveying pipeline; 8. Pressure regulating valve; 9. Stripping liquid discharge pipeline; 10. Wastewater regulating valve; 11. Ammonia nitrogen wastewater pipeline; 12. Pipeline mixer; 13. pH meter; 14. Ammonia-rich tail gas conveying pipeline; 15. Cooler; 16. Branch pipe; 17. Concentrate circulation pipeline; 18. Ammonia water conveying pipeline; 19. Heat exchanger; 20. Flow regulating valve. Detailed Implementation

[0040] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0041] like Figure 1 As shown, a combined treatment device for sulfur-containing tail gas and ammonia nitrogen wastewater includes a scrubbing tower 1, a stripping tower 2 and an absorption tower 3. The scrubbing tower 1 is the tail gas scrubbing tower of the Claus sulfur recovery system and belongs to the sulfur recovery device. The stripping tower 2 is the stripping tower for the shifted gas in the coal chemical process and belongs to the shifting device. All of these are existing equipment. Only the absorption tower 3 is a newly added device.

[0042] like Figure 1 and Figure 2As shown, the top of the scrubbing tower 1 is used to receive sulfur-containing tail gas and ammonia water transported by the absorption tower 3. The sulfur-containing tail gas is dispersed and transported downwards at the top of the scrubbing tower 1, and the ammonia water is sprayed at the top of the scrubbing tower 1. An alkali addition spray device is provided in the middle of the scrubbing tower 1. The alkali addition spray device is equipped with an alkali regulating valve 4 for adjusting the amount of alkali added. A scrubbing liquid circulation spray device is provided inside the scrubbing tower 1. The scrubbing liquid circulation spray device is located above the alkali addition spray device. A scrubbing liquid discharge pipeline 5, a scrubbing liquid circulation pipeline 6, and a tail gas conveying pipeline 7 are provided at the bottom of the scrubbing tower 1. The scrubbing liquid discharge pipeline 5 is used to discharge the scrubbing tower bottom liquid. The scrubbing liquid circulation pipeline 6 is connected to the scrubbing liquid circulation spray device. A pressure regulating valve 8 is provided on the tail gas conveying pipeline 7 for adjusting the gas flow pressure.

[0043] like Figure 1 and Figure 3 As shown, the lower part of the stripping tower 2 is connected to the tail gas conveying pipeline 7 to receive the tail gas after washing by the washing tower 1. The bottom of the stripping tower 2 is connected to the stripping liquid discharge pipeline 9 for discharging the stripping tower bottom liquid. The stripping liquid discharge pipeline 9 is equipped with a wastewater regulating valve 10. The upper part of the stripping tower 2 is connected to the ammonia nitrogen wastewater pipeline 11 and is equipped with an ammonia nitrogen wastewater spray device. The washing liquid discharge pipeline 5 is connected to the ammonia nitrogen wastewater pipeline 11, and a pipeline mixer 12 is installed on the ammonia nitrogen wastewater pipeline 11. The pipeline mixer 12 is located between the washing liquid discharge pipeline 5 and the ammonia nitrogen wastewater pipeline 11 and the stripping tower 2. A pH meter 13 is installed at the entrance of the ammonia nitrogen wastewater pipeline 11 to the stripping tower 2. It is used in conjunction with the alkali regulating valve 4 to adjust the system pH and promote the absorption and decomposition of sulfur. The top of the stripping tower 2 is connected to the ammonia-rich tail gas conveying pipeline 14, and a cooler 15 is installed on the ammonia-rich tail gas conveying pipeline 14.

[0044] like Figure 1 and Figure 4 As shown, the lower part of the absorption tower 3 is connected to the ammonia-rich tail gas conveying pipeline 14. A spray absorption device is installed inside the absorption tower 3. A branch pipe 16 is provided on the gas stripping liquid discharge pipeline 9, and the branch pipe 16 is connected to the spray absorption device at the top of the absorption tower 3. The bottom end of the absorption tower 3 is connected to the concentrated liquid circulation pipeline 17. A concentrated liquid circulation spray device is installed inside the absorption tower 3. The concentrated liquid circulation spray device is located below the spray absorption device and is connected to the concentrated liquid circulation pipeline 17. The top of the absorption tower 3 is connected to the boiler via a waste gas pipeline. The bottom end of the absorption tower 3 is also connected to an ammonia water conveying pipeline 18, which is used to convey ammonia water to the top of the scrubbing tower 1.

[0045] A heat exchanger 19 is provided on the stripping liquid discharge pipeline 9. The hot fluid of the heat exchanger 19 is the bottom liquid of the stripping tower 2, and the cold fluid is the ammonia nitrogen wastewater from the ammonia nitrogen wastewater pipeline 11.

[0046] Flow regulating valves 20 are installed on the ammonia water delivery pipeline 18, the washing liquid circulation pipeline 6, the concentrate circulation pipeline 17, and the branch pipe 16.

[0047] A method for the combined treatment of sulfur-containing tail gas and ammonia nitrogen wastewater includes the following steps:

[0048] Step S1: The tail gas from the Claus sulfur recovery unit comes into contact with ammonia water in the scrubbing tower 1 in a co-current flow to absorb sulfur dust and SO2 gas in the tail gas; the gas is discharged from the bottom of the scrubbing tower 1 to the stripping tower 2, part of the bottom liquid is circulated and sprayed, and the other part is mixed with the ammonia nitrogen wastewater in the stripping tower 2 to heat the wastewater and promote the discharge of ammonia gas.

[0049] Step S2: The scrubbing gas from scrubbing tower 1 comes into countercurrent contact with the ammonia nitrogen wastewater in stripping tower 2, causing ammonia gas to be released from the ammonia nitrogen wastewater, and the bottom liquid of stripping tower 2 is discharged.

[0050] Step S3: The ammonia-rich tail gas from stripping tower 2 is cooled and then comes into countercurrent contact with a portion of the waste liquid discharged from the bottom of stripping tower 2 in absorption tower 3 to absorb ammonia. The bottom liquid is ammonia water. A portion of the ammonia water in the bottom liquid of absorption tower 3 is sent to scrubbing tower 1 to treat the sulfur-containing tail gas, while the other portion of the ammonia water is circulated and sprayed.

[0051] The ammonia nitrogen wastewater undergoes heat exchange with the bottom liquid from the stripping tower 2 before being discharged.

[0052] After being treated by the Claus sulfur recovery unit, the sulfur-containing tail gas flow rate of Claus acid gas is 2000 Nm³. 3 The sulfur dust, containing 0.5% SO2 and 5 mg / L sulfur dust, is discharged at a temperature of 120-130℃ per hour into the top of scrubbing tower 1. There, it comes into contact with the ammonia water sprayed from the top of scrubbing tower 1 in a co-current flow. The sulfur dust reacts with the sprayed ammonia water at a depth of 0.7 m. 3 A 5% ammonia solution at a concentration of approximately 5% per hour forms a concentrated ammonia phase at a high temperature of 120-130℃, increasing the probability of ammonia reacting with sulfur dust to form soluble ammonium sulfide. This reacts to remove approximately 25% of the sulfur dust from the sulfur-containing tail gas. The sulfur-containing tail gas, still containing sulfur dust, continues to flow downwards and comes into contact with the alkaline reflux liquid sprayed in the middle of scrubbing tower 1. The sulfur dust continues to react with this liquid, removing approximately 30% of the sulfur dust. The sulfur-containing tail gas, still containing sulfur dust, continues to flow downwards and comes into contact with the bottom layer of scrubbing tower 1 sprayed with approximately 25% sulfur dust at a concentration of 0.5m. 3The sulfur dust is reacted with a NaOH solution at a temperature of 120-130℃ to form a concentrated NaOH reaction zone, which removes 35% of the sulfur dust. The amount of alkali added is controlled to maintain a pH of 8-9 on the pH meter. After the reaction, about 90% of the nano-sized sulfur particles are removed from the trays of scrubbing tower 1. The remaining sulfur particles enter the bottom of the tower with the alkaline liquid phase and continue to react there, ultimately removing about 95% of the sulfur particles. The sulfur content in the tail gas is reduced to 0.25 mg / L. The alkali is added in a co-current, segmented manner to solve the problem of sulfur dust clogging the trays. The waste heat of the tail gas is used to heat the alkali, providing a good reaction environment. The alkali is added at the bottom to prevent premature addition and decomposition of ammonia. At the same time, the sulfur dioxide in the tail gas undergoes a neutralization reaction in the tower to generate sulfite, which solves the problem of subsequent acidic gas corrosion. The pressure at the top of the scrubbing tower is controlled at 15 kPaG by a pressure regulating valve to ensure the temperature of the scrubbing gas entering the stripping tower.

[0053] The reaction formula for the disproportionation reaction of the sulfur powder is as follows:

[0054] 6NH3·H20+3S=2(NH4)2S+(NH4)2SO3+3H20

[0055] 6NaOH+3S=2(Na)2S+(Na)2SO3+3H20

[0056] The temperature of the scrubbing gas, which removes sulfur dust at a rate of 2000 Nm³ / h, is reduced to approximately 90-100℃ and enters stripping tower 2. This gas serves as the heat source and stripping gas for stripping tower 2. It mixes with the bottom liquid from scrubbing tower 1 and ammonia nitrogen wastewater preheated by heat exchanger 19 via a pipe mixer 12 on the ammonia nitrogen wastewater pipeline 11 before entering the upper part of stripping tower 2. (The ammonia nitrogen wastewater is obtained after the shifted gas has been scrubbed by S2002 water spray and is 10m³ / h). 3 The pressure is 3 MPaG, containing 5000 ppm of wastewater. The alkali addition is controlled by the alkali regulating valve 4, and the pH meter 13 is kept at 8-9. After stripping, the ammonia-rich tail gas is cooled to 40℃ by the circulating water in the cooler 15 before entering the absorption tower. The wastewater after stripping in the stripping tower 2 contains 20-30 mg / L of ammonia nitrogen, approximately 9 m³. 3 / h, after being pressurized by the bottom liquid pump of stripping tower 2, the wastewater is cooled by heat exchanger 19. After stripping, the wastewater is sent to the wastewater treatment regulating tank after the bottom liquid level of stripping tower 2 is adjusted by wastewater regulating valve 10.

[0057] The ammonia-rich tail gas is cooled to 40°C by circulating water in cooler 15 before entering the lower part of absorber 3, where it meets the top spray at a flow rate of approximately 1 m³ / s. 3 The liquid in the bottom of stripping tower 2 at a rate of / h countercurrently contacts and absorbs ammonia nitrogen in the gas phase, forming ammonia water which enters the bottom of absorption tower 3. After being pressurized by the bottom liquid pump, part of the liquid in the bottom of absorption tower 3 is used as reflux in the middle of absorption tower 3 to concentrate the ammonia water, and the other part (5% dilute ammonia water) is sent to the top of washing tower 1.

[0058] Sulfur recovery tail gas at 120-130℃ replaces 1.27MPa low-pressure steam for heat recovery, reducing steam consumption during stripping by 2t / h, thus saving energy and reducing consumption. By adding alkali to control the pH of the ammonia nitrogen wastewater entering the stripping tower, the stripping of ammonia is promoted. After adding an appropriate amount of alkali to the ammonia nitrogen wastewater, sulfur components in the sulfur-containing tail gas can be removed, and the ammonia nitrogen removal rate can be accelerated, which greatly reduces the ammonia nitrogen in the shift washing liquid and solves the problem of difficult treatment due to the high content of shift condensate.

Claims

1. A combined treatment device for sulfur-containing tail gas and ammonia nitrogen wastewater, characterized in that, This includes a sulfur-containing tail gas treatment tower, an ammonia nitrogen wastewater treatment tower, and an ammonia gas collection tower; The gas phase exit line of the sulfur-containing tail gas treatment tower is connected to the inlet of the ammonia nitrogen wastewater treatment tower via the tail gas conveying pipeline (7). The top gas phase exit line of the ammonia nitrogen wastewater treatment tower is connected to the ammonia collection tower via the ammonia-rich tail gas conveying pipeline (14). The liquid phase exit line of the ammonia collection tower is connected to the sulfur-containing tail gas treatment tower via the ammonia water conveying pipeline (18). The sulfur-containing tail gas treatment tower is a Claus sulfur recovery tail gas scrubbing tower (1), the ammonia nitrogen wastewater treatment tower is a stripping tower (2) in the coal chemical process, and the ammonia gas collection tower is an absorption tower (3). The top of the scrubbing tower (1) is used to receive sulfur-containing tail gas and ammonia water transported by the absorption tower (3). After the Claus acid gas is treated by the Claus sulfur recovery unit, the flow rate of the sulfur-containing tail gas is 2000 Nm³. 3 The temperature is 120-130℃, containing 0.5% SO2 and 5mg / L sulfur dust. It enters the top of the scrubbing tower (1) and comes into contact with the ammonia water sprayed from the top of the scrubbing tower (1) in a co-current flow. An alkali spraying device is installed in the middle of the scrubbing tower (1). The sulfur dust and the sprayed ammonia water are mixed together. 3 A 5% ammonia solution per hour forms a concentrated ammonia phase at 120-130℃, increasing the probability of ammonia reacting with sulfur dust to generate soluble ammonium sulfide, which reacts to remove 25% of the sulfur dust in the sulfur-containing tail gas. The sulfur-containing tail gas carrying sulfur dust continues to flow downwards and comes into contact with the alkaline reflux liquid sprayed in the middle of the scrubbing tower (1). The sulfur powder continues to react with the ammonia solution to remove 30% of the sulfur dust. The sulfur-containing tail gas carrying sulfur dust continues to flow downwards and comes into contact with the alkaline reflux liquid sprayed at the bottom of the scrubbing tower (1) with a mass concentration of 0.5m. 3 When in contact with a / L NaOH solution at a high temperature of 120-130℃, a concentrated NaOH reaction zone is formed, which reacts and removes 35% of the sulfur dust, 2000Nm 3 The temperature of the washing gas used to remove sulfur dust is reduced to 90-100℃ and enters the stripping tower (2). It serves as the stripping heat source and stripping gas for the stripping tower (2). It is mixed with the bottom liquid from the washing tower (1) and the ammonia nitrogen wastewater preheated by the heat exchanger (19) through the pipe mixer (12) on the ammonia nitrogen wastewater pipeline (11) and then enters the upper part of the stripping tower (2). The amount of alkali added is controlled by the alkali regulating valve (4). The amount of alkali added is based on controlling the pH meter (13) reading to 8-9. After the reaction, 90% of the nano-sized sulfur particles are removed from the tower plates of the washing tower (1). The remaining sulfur particles enter the bottom of the tower with the alkaline liquid phase and continue to react in the bottom of the tower. Finally, 95% of the sulfur particles are reacted and the sulfur content of the tail gas is reduced to 0.25 mg / L. The washing liquid discharge pipeline (5) and the tail gas conveying pipeline (7) are installed at the bottom of the washing tower (1). The lower part of the stripping tower (2) is connected to the tail gas conveying pipeline (7), the bottom of the stripping tower (2) is connected to the stripping liquid discharge pipeline (9), the upper part of the stripping tower (2) is connected to the ammonia nitrogen wastewater pipeline (11) and is equipped with an ammonia nitrogen wastewater spraying device, and the top of the stripping tower (2) is connected to the ammonia-rich tail gas conveying pipeline (14). The lower part of the absorption tower (3) is connected to the ammonia-rich tail gas conveying pipeline (14), and the lower end of the absorption tower (3) is connected to the ammonia water conveying pipeline (18) for conveying ammonia water to the top of the scrubbing tower (1). A spray absorption device is installed inside the absorption tower (3), and the top of the absorption tower (3) is connected to the boiler through the waste gas pipeline. The gas stripping liquid discharge pipeline (9) is provided with a branch pipe (16), which is connected to the spray absorption device at the top of the absorption tower (3).

2. The combined treatment device for sulfur-containing tail gas and ammonia nitrogen wastewater according to claim 1, characterized in that, The washing liquid discharge pipeline (5) is connected to the ammonia nitrogen wastewater pipeline (11), and a pipeline mixer (12) is provided on the ammonia nitrogen wastewater pipeline (11).

3. The combined treatment device for sulfur-containing tail gas and ammonia nitrogen wastewater according to claim 1, characterized in that, The washing tower (1) is equipped with a washing liquid circulation spraying device inside the tower body. The washing liquid circulation spraying device is located above the alkali spraying device. The lower end of the washing tower (1) is also connected to a washing liquid circulation pipeline (6), which is connected to the washing liquid circulation spraying device.

4. The combined treatment device for sulfur-containing tail gas and ammonia nitrogen wastewater according to claim 1, characterized in that, The bottom of the absorption tower (3) is also connected to a concentrated liquid circulation pipeline (17). The absorption tower (3) is equipped with a concentrated liquid circulation spray device, which is connected to the concentrated liquid circulation pipeline (17).

5. The combined treatment device for sulfur-containing tail gas and ammonia nitrogen wastewater according to claim 1, characterized in that, The stripping liquid discharge pipeline (9) is equipped with a heat exchanger (19), the hot fluid of the heat exchanger (19) is the bottom liquid of the stripping tower (2), and the cold fluid is the ammonia nitrogen wastewater from the ammonia nitrogen wastewater pipeline (11).

6. The combined treatment device for sulfur-containing tail gas and ammonia nitrogen wastewater according to claim 1, characterized in that, A pH meter (13) is installed on the ammonia nitrogen wastewater pipeline (11) near the stripping tower (2).

7. A method for the combined treatment of sulfur-containing tail gas and ammonia nitrogen wastewater, using the combined treatment device for sulfur-containing tail gas and ammonia nitrogen wastewater as described in any one of claims 1-6, characterized in that, Includes the following steps: Step S1: Ammonia nitrogen wastewater is stripped by a stripping tower to obtain stripping wastewater and stripping gas, of which the stripping wastewater is discharged externally; Step S2: The stripping gas obtained in step S1 is absorbed and concentrated to obtain ammonia water; Step S3: The ammonia water obtained in step S2 is used to contact with sulfur-containing tail gas to obtain tail gas and washing liquid. The washing liquid is added to the ammonia nitrogen wastewater in step S1, and the tail gas is used to strip the ammonia nitrogen wastewater in step S1.

8. The method for combined treatment of sulfur-containing tail gas and ammonia nitrogen wastewater according to claim 7, characterized in that, The ammonia nitrogen wastewater undergoes heat exchange with the bottom liquid from the stripping tower (2) before being discharged.

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