Tail gas deamination system and method

Abstract

The invention provides a tail gas deamination system and method, and relates to the technical field of chemical production tail gas system treatment. The tail gas deamination system comprises an absorption device used for absorbing ammonia gas in tail gas by using an absorbent, the absorbent becomes a rich solution after absorbing the ammonia gas and enters an analysis device, and the tail gas without part of the ammonia gas becomes deaminated tail gas and enters a gas washing device; the gas washing device is used for absorbing ammonia gas and impurities in the deamination tail gas to form secondary deamination tail gas, cooling the secondary deamination tail gas, removing liquid drops in the secondary deamination tail gas and then discharging the secondary deamination tail gas; the desorption device is used for desorbing the rich solution by utilizing desorption steam so as to release ammonia gas in the rich solution, and the rich solution becomes barren solution after releasing the ammonia gas and is conveyed to the absorption device; and the cooling device is used for cooling the ammonia gas released from the desorption device to form liquid ammonia. The tail gas deamination system and the tail gas deamination method provided by the invention solve the problem that in the prior art, a product formed in the deamination process is difficult to release ammonia gas later.

Description

Technical Field

[0001] The present invention relates to the technical field of chemical production tail gas system treatment, in particular to a tail gas deamination system and a tail gas deamination method. Background Art

[0002] In the current trend, the control of sulfide emissions in the treatment of industrial furnace exhaust gas in thermal power plants is increasing year by year, and there is no shortage of treatment devices that control the sulfur dioxide content at 100 mg / m³; but the exhaust gas also contains ammonia, but the existing technology for the emission treatment of ammonia-containing exhaust gas is mainly treated by hollow fiber membrane heat exchangers. The main problem with this type of technology is that due to the presence of solid, dust and particulate impurities in the exhaust gas, pre-washing is required, and the control of ammonium sulfate crystallization discharge after sulfur deamination is difficult, resulting in the problem of being unable to maintain continuous operation, and this technology is also mostly limited to the exhaust gas processing capacity.

[0003] Therefore, there is an urgent need for a device that can solve at least one of the above problems. Summary of the invention

[0004] The purpose of the embodiments of the present invention is to provide a tail gas deamination system and method, which is used to solve the problem in the prior art that it is difficult to release ammonia from the products formed during the deamination process.

[0005] In order to achieve the above object, the present invention provides a tail gas deamination system on one hand, the tail gas deamination system comprising: An absorption device is used to absorb ammonia in the tail gas by using an absorbent. After the absorbent absorbs ammonia, it becomes a rich liquid and enters the analysis device. The tail gas that loses part of the ammonia becomes a deammoniation tail gas and enters the scrubbing device; The scrubber is used to absorb ammonia and impurities in the ammonia tail gas to form secondary deammoniation tail gas, and to cool and remove droplets in the secondary deammoniation tail gas before discharging it; The desorption device is used to desorb the rich liquid by using desorption steam to release ammonia in the rich liquid. After the rich liquid releases ammonia, it becomes lean liquid and is transported to the absorption device; A cooling device is used to cool the ammonia gas released from the analysis device to form liquid ammonia.

[0006] Specifically, the absorption device includes: an absorption tower, an absorbent supply assembly and a plurality of first spray plates; A plurality of first spray plates are layered in the absorption tower, and the absorbent is sprayed into the absorption tower through the plurality of first spray plates; The absorbent supply assembly is used to deliver absorbent to the plurality of first spray plates; The tail gas entering the absorption tower can fully contact with the absorbent in the absorption tower. After the absorbent absorbs the ammonia in the tail gas, it becomes rich liquid and gathers at the bottom of the absorption tower. The tail gas that loses part of the ammonia becomes deammoniation tail gas and is discharged from the absorption tower.

[0007] Specifically, a plurality of grids are arranged at the bottom of the absorption tower, and impurities in the rich liquid are filtered out through the grids.

[0008] Specifically, the spraying areas of the absorbent sprayed from the first spray plates of adjacent layers in the absorption tower are different.

[0009] Specifically, the absorbent supply assembly includes: an inclined tube settling tank, a liquid collecting tank, a separator and a distribution assembly; The inclined tube sedimentation tank is connected to the rich liquid outlet of the absorption tower and is used to precipitate the rich liquid discharged from the rich liquid outlet so that the particulate impurities in the rich liquid are precipitated in the inclined tube sedimentation tank; The liquid collecting box is connected to the inclined tube sedimentation tank and the analytical device, and is used to recover the rich liquid and the lean liquid after precipitation to form a mixed liquid; The distribution component is connected to the liquid collection tank and the plurality of first spray plates, and the distribution component is used to transport the mixed liquid in the liquid collection tank to each first spray plate as an absorbent; The separator is connected to the delivery component and the analysis device, and is used to recover the mixed liquid overflowed from the delivery component and heat the mixed liquid so that the mixed liquid becomes a rich liquid again and is transported to the analysis device.

[0010] Specifically, the absorption device further includes: a second spray plate, which is arranged in the absorption tower and is located below all the first spray plates, the second spray plate is connected to the liquid collecting tank, and is used to spray the mixed liquid in the liquid collecting tank into the absorption tower as an absorbent; The spraying area of ​​the second spray plate is different from the spraying area of ​​the adjacent first spray plate.

[0011] Specifically, the scrubber comprises: a scrubber tower, a first cooler, an electric demister and a scrubbing liquid supply assembly; The washing liquid supply assembly is used to supply washing liquid into the scrubbing tower; The scrubber is connected to the absorption tower, and a filler is arranged in the scrubber. The scrubber is used to absorb ammonia in the deammoniation tail gas with a washing liquid and filter out impurities in the deammoniation tail gas with the filler to form a secondary deammoniation tail gas; The first cooler is used to cool the secondary deammoniation tail gas; The electric demister is used to remove liquid droplets in the cooled secondary deammoniation tail gas.

[0012] Specifically, the analysis device includes: an analysis tower connected to the separator and the liquid collecting tank, used to analyze the rich liquid from the separator using analysis steam to release ammonia in the rich liquid, and the rich liquid after releasing ammonia becomes lean liquid and enters the liquid collecting tank.

[0013] Specifically, the analysis device further includes: a first heat exchanger, which is arranged between the analysis tower and the separator and is used to preliminarily heat the rich liquid from the separator by using the ammonia released by the analysis tower.

[0014] Another aspect of the present invention provides a tail gas deamination method, which is implemented based on any of the tail gas deamination systems described above, and the tail gas deamination method comprises: The absorbent is used to absorb ammonia in the tail gas, and the absorbent becomes a rich liquid after absorbing ammonia, and the tail gas that loses part of the ammonia becomes deammoniation tail gas; The washing liquid is used to absorb the ammonia in the deammoniation tail gas, and the filler is used to filter out the impurities in the deammoniation tail gas to form a secondary deammoniation tail gas, which is discharged after cooling and removing the droplets in the secondary deammoniation tail gas; Decomposing the rich liquid by using decomposition steam to release ammonia in the rich liquid; The ammonia gas is cooled to form liquid ammonia.

[0015] The tail gas deammonification system provided by the present invention comprises an absorption device that absorbs ammonia in the tail gas by an absorbent, and the absorbent becomes a rich liquid after absorbing ammonia. The tail gas that loses part of ammonia becomes a deammonified tail gas and enters a scrubber after being discharged from the absorption device. The scrubber absorbs ammonia in the deammonified tail gas again and filters out impurities in the deammonified tail gas. The deammonified tail gas becomes a secondary deammonified tail gas, and the secondary deammonified tail gas is cooled and the liquid droplets of the secondary deammonified tail gas are removed before the secondary deammonified tail gas is discharged. The rich liquid enters a decomposition device and decomposes ammonia in the rich liquid by decomposition steam. The released ammonia enters a cooling device after being discharged from the decomposition device. The cooling device cools the ammonia to cool the ammonia into liquid ammonia for storage. The tail gas deammonification system and method provided by the present invention first become a rich liquid after absorbing ammonia in the tail gas by an absorbent, and then decomposes the rich liquid by decomposition steam to release ammonia in the rich liquid, and cools the ammonia to liquefy the ammonia into liquid ammonia, which is convenient for storage, and solves the problem of difficulty in releasing ammonia in the products formed in the deammonification process in the prior art.

[0016] Other features and advantages of the embodiments of the present invention will be described in detail in the subsequent detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The accompanying drawings are used to provide a further understanding of the embodiments of the present invention and constitute a part of the specification. Together with the following specific implementations, they are used to explain the embodiments of the present invention, but do not constitute a limitation on the embodiments of the present invention. In the accompanying drawings: Figure 1Schematic diagram of the structure of the tail gas deamination system provided by an embodiment of the present invention; Figure 2 is a schematic diagram of the structure of an absorption tower in a tail gas deammoniation system provided in an embodiment of the present invention; Figure 3 Schematic diagram of the bottom structure of an absorption tower in a tail gas deammoniation system provided in an embodiment of the present invention; Figure 4 It is a schematic diagram of the layout of the first pipeline component in the tail gas deamination system provided in an embodiment of the present invention.

[0018] Description of Reference Numerals 1-absorption device; 2-gas scrubber; 3-analyzer; 4-cooling device; 5-liquid ammonia storage tank; 11-absorption tower; 110-smoke inlet; 111-smoke outlet; 112-liquid outlet; 113-liquid inlet; 12-absorbent supply assembly; 13-first spray plate; 14-grid; 15-second spray plate; 121-inclined tube sedimentation tank; 122-liquid collecting tank; 123-separator; 124-distribution assembly; 125 - pipeline pump; 126- first circulation pump; 127- second circulation pump; 1241- collection tank; 1242- distribution pump; 21- scrubbing tower; 22- first cooler; 23- electric demister; 24- washing liquid supply assembly; 25- negative pressure pipeline; 31- analysis tower; 32- first heat exchanger; 33- equalizer; 210- tail gas inlet; 211- tail gas outlet; 212- washing liquid inlet; 241- washing liquid tank; 242- acid replenishing tank. DETAILED DESCRIPTION

[0019] The specific implementation of the embodiment of the present invention is described in detail below in conjunction with the accompanying drawings. It should be understood that the specific implementation described here is only used to illustrate and explain the embodiment of the present invention, and is not used to limit the embodiment of the present invention.

[0020] Figure 1 It is a schematic diagram of the structure of the tail gas deamination system; Figure 2 It is a schematic diagram of the structure of the absorption tower in the tail gas deammoniation system; Figure 3 It is a schematic diagram of the bottom structure of the absorption tower in the tail gas deammoniation system; Figure 4 Schematic diagram of the layout of the first pipeline component in the tail gas deamination system.

[0021] like Figure 1-Figure 4 As shown, the present invention provides a tail gas deamination system, the tail gas deamination system comprising: Absorption device 1, used for absorbing ammonia in tail gas by using absorbent, the absorbent becomes rich liquid after absorbing ammonia and enters into analysis device 3, the tail gas which loses part of ammonia becomes deammoniation tail gas and enters into scrubbing device 2; The scrubber 2 is used to absorb ammonia and impurities in the deammoniation tail gas to form secondary deammoniation tail gas, and to cool and remove droplets in the secondary deammoniation tail gas before discharging it; The analysis device 3 is used to analyze the rich liquid by using the analysis steam to release the ammonia in the rich liquid. After the rich liquid releases the ammonia, it becomes the lean liquid and is transported to the absorption device 1; The cooling device 4 is used to cool the ammonia gas released from the analysis device 3 to form liquid ammonia.

[0022] In the tail gas deammonification system provided by the present invention, the absorption device 1 absorbs ammonia in the tail gas by using the incoming absorbent, and the absorbent becomes rich liquid after absorbing ammonia. Part of the ammonia in the tail gas is absorbed to become deammonified tail gas, and the deammonified tail gas is discharged from the absorption device and enters the scrubbing device 2. The scrubbing device 2 absorbs the remaining ammonia in the deammonified tail gas and filters out impurities in the deammonified tail gas, and the deammonified tail gas becomes secondary deammonified tail gas. After the secondary deammonified tail gas is cooled and the droplets are removed, the secondary deammonified tail gas is discharged, and the ammonia in the tail gas is thoroughly absorbed by the scrubbing device 2; the rich liquid in the absorption device 1 enters the analysis device 3, and the analysis device 3 uses the incoming analysis steam to fully contact with the rich liquid to analyze the rich liquid so that the ammonia in the rich liquid is released, and the released ammonia enters the cooling device 4 for cooling and liquefaction to become liquid ammonia, which is convenient for storage, and solves the problem of difficulty in releasing ammonia in the product formed in the deammonification process in the prior art.

[0023] In one embodiment, the absorbent is dilute sulfuric acid, and the absorbent is configured with the concentration of dilute sulfuric acid in the hollow ion membrane method, and the absorbent concentration is 10%-20% dilute sulfuric acid, preferably 12% dilute sulfuric acid as the absorbent, and the dilute sulfuric acid enters the absorption device 1 and fully contacts with the tail gas to produce a reaction: NH3+H2SO4→(NH4)2SO4 (positive reaction), Ammonia in the tail gas reacts with dilute sulfuric acid to generate ammonium sulfate solution, i.e., a rich liquid. After the ammonium sulfate is dissolved, it enters the analysis device 3, and the ammonium sulfate solution is analyzed by analysis steam to release ammonia. The released ammonia is cooled by the cooling device 4 and becomes liquid ammonia for storage.

[0024] In one embodiment, Figure 1 As shown, the absorption device 1 comprises: an absorption tower 11, an absorbent supply assembly 12 and a plurality of first spray plates 13; A plurality of first spray plates 13 are layered in the absorption tower 11, and the absorbent is sprayed into the absorption tower 11 through the plurality of first spray plates 13; The absorbent supply assembly 12 is used to deliver absorbent to the plurality of first spray plates 13; The tail gas entering the absorption tower 11 can fully contact with the absorbent in the absorption tower 11. The absorbent absorbs ammonia in the tail gas and becomes rich liquid and gathers at the bottom of the absorption tower 11. The tail gas that loses part of the ammonia becomes deammoniation tail gas and is discharged from the absorption tower 11.

[0025] A plurality of grids 14 are disposed at the bottom of the absorption tower 11 , and impurities in the rich liquid are filtered out through the grids 14 .

[0026] The absorbent sprayed from the first spray plates 13 of adjacent layers in the absorption tower 11 has different spraying areas.

[0027] The absorbent supply assembly 12 comprises: an inclined tube settling tank 121, a liquid collecting tank 122, a separator 123 and a distribution assembly 124; The inclined tube settling tank 121 is connected to the rich liquid outlet of the absorption tower 11 and is used to precipitate the rich liquid discharged from the rich liquid outlet so that the particulate impurities in the rich liquid are precipitated in the inclined tube settling tank 121; The liquid collecting box 122 is connected to the inclined tube sedimentation tank 121 and the analytical device 3, and is used to recover the rich liquid and the lean liquid after precipitation to form a mixed liquid; The distribution component 124 is connected to the liquid collection tank 122 and the plurality of first spray plates 13, and the distribution component 124 is used to transport the mixed liquid in the liquid collection tank 122 as an absorbent to each first spray plate 13; The separator 123 is connected to the delivery component 124 and the analysis device 3 , and is used to recover the mixed liquid overflowing from the delivery component 124 , and heat the mixed liquid so that the mixed liquid becomes a rich liquid again and is transported to the analysis device 3 .

[0028] The absorption device 1 also includes: a second spray plate 15, which is arranged in the absorption tower 11 and is located below all the first spray plates 13. The second spray plate 15 is connected to the liquid collecting tank 122 and is used to spray the mixed liquid in the liquid collecting tank 122 into the absorption tower 11 as an absorbent; wherein the spraying area of ​​the second spray plate 15 is different from the spraying area of ​​the adjacent first spray plate 13.

[0029] The absorption tower 11 has a flue gas inlet 110, a flue gas outlet 111, a liquid outlet 112 and a plurality of liquid inlets 113. The flue gas inlet 110 and the liquid outlet 112 are both arranged at the bottom of the absorption tower 11, and the flue gas inlet 110 is located above the liquid outlet 112. The flue gas outlet 111 is arranged at the top of the absorption tower 11. The liquid inlets 113 are arranged in layers on the absorption tower 11. A second spray plate 15 is arranged at the liquid inlet 113 at the bottom of the absorption tower 11. The remaining liquid inlets 113 are arranged at the bottom of the absorption tower 11. A first spray plate 13 is arranged at each layer. The tail gas enters the absorption tower 11 from the flue gas inlet 110. The tail gas rises from the bottom to the top and reacts with the dilute sulfuric acid sprayed from the second spray plate 15 and the first spray plate 13 above. The dilute sulfuric acid reacts with ammonia to generate ammonium sulfate solution which accumulates at the bottom of the absorption tower 11. In order to ensure that the ammonia and the dilute sulfuric acid are fully in contact, the spraying areas of the first spray plates 13 of adjacent layers are different, and the spraying areas of the second spray plate 15 and the adjacent first spray plate 13 are different. Figure 2 and Figure 3 As shown, the center of one layer of the first spray plate 13 is a hollow area, and the spray holes of the first spray plate 13 are arranged along the edge of the first spray plate 13, so that the dilute sulfuric acid sprayed from the first spray plate 13 of this layer is sprayed around the hollow area, and the exhaust gas can flow upward from the hollow area of ​​the first spray plate 13, and the spray holes of the first spray plate 13 of another layer adjacent thereto are arranged at the center position, and through holes are arranged at the edge of the first spray plate 13, and the dilute sulfuric acid sprayed from the first spray plate 13 of this layer is sprayed from the center position, and the spray holes of the second spray plate 15 arranged at the bottom of the absorption tower 11 are arranged in the same manner as the adjacent first spray plate 15. The arrangement method of the spray holes of the spray plate 13 is related. If the spray holes of the adjacent first spray plate 13 are arranged at the center position, the spray holes of the second spray plate 15 are arranged along the edge of the second spray plate 15. If the spray holes of the adjacent first spray plate 13 are arranged at the edge of the first spray plate 13, the spray holes of the second spray plate 15 are arranged at the center position; after the exhaust gas enters the absorption tower 11, it rises upward and reacts with each layer of sprayed dilute sulfuric acid. The dilute sulfuric acid sprayed layer by layer reacts with the exhaust gas to ensure that the exhaust gas is fully in contact with the dilute sulfuric acid, so that the dilute sulfuric acid as an absorbent can fully absorb the ammonia in the exhaust gas.

[0030] After the reaction of dilute sulfuric acid and ammonia, an ammonium sulfate solution is formed and sprinkled to the bottom of the absorption tower 11. In order to prevent the impurities in the ammonium sulfate solution from clogging the bottom of the absorption tower 11, a plurality of grids 14 are arranged at the bottom of the absorption tower 11. The grids 14 are inclined plate grids. The second spray plate 15 is arranged above the flue gas inlet 110, and the grids 14 are arranged below the flue gas inlet 110. The falling ammonium sulfate solution can intercept the impurities in the ammonium sulfate solution when it sprinkles to the bottom of the absorption tower 11. At the same time, the grids 14 can also prevent the ammonium sulfate solution from volatilizing.

[0031] The inclined tube sedimentation tank 121 is connected to the liquid outlet 112 at the bottom of the absorption tower 11 through a first pipeline assembly, such as Figure 4 As shown, the first pipeline assembly includes a first main pipeline and a plurality of first branch pipelines, one end of the first main pipeline is connected to the liquid outlet 112, and the other end of the first main pipeline is connected to the plurality of first branch pipelines at the same time, and a pipeline pump 125 is arranged on each first branch pipeline, and the pipeline pump 125 is used to pump the rich liquid at the bottom of the absorption tower 11 through the corresponding first branch pipeline to the inclined tube sedimentation tank 121, and the rich liquid enters the inclined tube sedimentation tank 121 for sedimentation, and the particulate impurities in the rich liquid are precipitated at the bottom of the inclined tube sedimentation tank 121, and the inclined tube sedimentation tank The rich liquid at the top of 121 overflows into the liquid collecting tank 122, and the liquid collecting tank 122 also receives the lean liquid in the analysis tower 31. The rich liquid and the lean liquid are mixed in the liquid collecting tank 122 to form a mixed liquid, which can be used as an absorbent. The liquid collecting tank 122 is connected to the second spray plate 15 through a second pipe, and a first circulation pump 126 is arranged on the second pipe. The mixed liquid in the liquid collecting tank 122 is pumped to the second spray plate 15 by the first circulation pump 126, and the absorbent is sprayed into the absorption tower 11 through the second spray plate 15.

[0032] like Figure 1 As shown, the distribution component 124 includes a plurality of collecting tanks 1241 and a plurality of distribution pumps 1242. Each collecting tank 1241 is connected to the liquid collecting tank 122 through a third pipeline. A second circulation pump 127 is arranged on the third pipeline. The mixed liquid in the liquid collecting tank 122 is pumped into each collecting tank 1241 through the second circulation pump 127. Each collecting tank 1241 is connected to a first spray plate 13, and each first spray plate 13 is connected to the corresponding collecting tank 1241 through a fourth pipeline. A distribution pump 1242 is arranged on each fourth pipeline. The mixed liquid in the corresponding collecting tank 1241 is pumped to the corresponding first spray plate 13 through the distribution pump 1242. The tray 13, the separator 123 is connected to each collecting tank 1241 and the separator 123 is also connected to the scrubber 2 through the negative pressure pipe 25. The separator 123 recovers the mixed liquid overflowing from each collecting tank 1241. The separator 123 can also heat the overflowed mixed liquid to make the mixed liquid rich again. The free gas generated when the mixed liquid is heated enters the scrubber 2 through the negative pressure pipe 25 to absorb ammonia in the free gas through the scrubber 2. In order to heat the mixed liquid in the separator 123, auxiliary steam can be introduced to heat the mixed liquid in the separator 123. The auxiliary steam heats the mixed liquid to 90°C-104°C to make the mixed liquid rich again.

[0033] In order to fully absorb ammonia in the tail gas, the scrubber 2 comprises: a scrubber 21, a first cooler 22, an electric demister 23 and a scrubbing liquid supply assembly 24; The washing liquid supply assembly 24 is used to supply washing liquid into the scrubbing tower 21; The scrubber 21 is connected to the absorption tower 11. A filler is arranged in the scrubber 21. The scrubber 21 is used to absorb ammonia in the deaminated tail gas with a washing liquid and filter out impurities in the deaminated tail gas with the filler to form a secondary deaminated tail gas. The first cooler 22 is used to cool the secondary deammoniation tail gas; The electric demister 23 is used to remove liquid droplets in the cooled secondary deammoniation tail gas.

[0034] The scrubber 21 has an exhaust gas inlet 210, an exhaust gas outlet 211, and a washing liquid inlet 212. The exhaust gas inlet 210 and the washing liquid inlet 212 are arranged at the top of the scrubber 21, and the exhaust gas outlet 211 is arranged at the bottom of the scrubber 21. The washing liquid inlet 212 is connected to the washing liquid supply component 24. The washing liquid supply component 24 supplies washing liquid into the scrubber 21 through the washing liquid inlet 212. The washing liquid is an acidic solution, for example, dilute sulfuric acid. The washing liquid enters the scrubber 21. The washing liquid supply component 24 includes a washing liquid tank 241 and an acid replenishing tank 242. The acid replenishing tank 242 is used to replenish washing liquid in the washing liquid tank 241. The washing liquid tank 241 is connected to the washing liquid inlet 212 of the scrubbing tower 21. The deammoniation tail gas enters the scrubbing tower 21 from the tail gas inlet 210 and flows to the tail gas outlet 211. While entering the scrubbing tower 21 for reaction, the impurities in the deammoniation tail gas are filtered by the filler arranged in the scrubbing tower 21. The remaining ammonia in the deammoniation tail gas is absorbed by the washing liquid to become the secondary deammoniation tail gas. The secondary deammoniation tail gas is discharged from the tail gas outlet 211 and then enters the first cooler 22. The first cooler 22 uses cooling water to exchange heat with the secondary deammoniation tail gas in the first cooler 22. The heat in the secondary deammoniation tail gas is absorbed by the cooling water to cool the secondary deammoniation tail gas. The cooled secondary deammoniation tail gas then enters the electric demister In 23, the droplets in the secondary deammoniation tail gas after cooling are removed by the electrostatic precipitator 23, and the secondary deammoniation tail gas after the droplets are removed is discharged from the electrostatic precipitator 23. In order to speed up the discharge of the secondary deammoniation tail gas from the electrostatic precipitator 23 after the droplets are removed, a plurality of induced draft fans are arranged at the gas outlet of the electrostatic precipitator 23, and the secondary deammoniation tail gas in the electrostatic precipitator 23 is guided to be discharged by the induced draft fans. The droplets removed from the secondary deammoniation tail gas in the electrostatic precipitator 23 enter the washing liquid pool 241.

[0035] In order to release ammonia in the rich liquid, the analysis device 3 includes: a analysis tower 31, which is connected to the separator 123 and the liquid collecting tank 122, and is used to use analysis steam to analyze the rich liquid from the separator 123 to release ammonia in the rich liquid. The rich liquid after the ammonia is released becomes a lean liquid and enters the liquid collecting tank 122.

[0036] The analysis device 3 further includes: a first heat exchanger 32 , which is disposed between the analysis tower 31 and the separator 123 and is used for preliminarily heating the rich liquid from the separator 123 by utilizing the ammonia released by the analysis tower 31 .

[0037] The analysis tower 31 has a rich liquid inlet, a lean liquid outlet, an ammonia outlet and a steam inlet. The rich liquid inlet and the ammonia outlet are both arranged at the top of the analysis tower 31, and the lean liquid outlet and the steam inlet are arranged at the bottom of the analysis tower 31. The rich liquid outlet of the separator 123 is connected to the rich liquid inlet of the analysis tower 31 through a fifth pipeline, and a rich liquid pump is arranged on the fifth pipeline to pump the rich liquid in the separator 123 into the analysis tower 31. The analysis steam enters the analysis tower 31 from the steam inlet. In order to make the analysis steam enter the analysis tower 31 evenly, an equalizer 33 is arranged in the analysis tower 31. The equalizer 33 allows the analysis steam to enter the analysis tower 31 evenly. The analysis steam flows from bottom to top and fully reacts with the rich liquid spilled from the top of the analysis tower 31. (NH4)2S04→NH3+H2S04 (reverse reaction), The temperature of the decomposition steam can reach 280°C-350°C. The ammonium sulfate solution as the rich liquid begins to decompose above 280°C, and the decomposition temperature reaches a maximum at 345°C. In order to improve the decomposition efficiency of the rich liquid, the rich liquid is preheated before entering the decomposition tower 31. The first heat exchanger 32 is arranged on the fifth pipeline. The first heat exchanger 32 is connected to the ammonia outlet of the decomposition tower 31. The decomposed ammonia enters the first heat exchanger 32 after being discharged from the ammonia outlet. The rich liquid first enters the first heat exchanger 32 to exchange heat with the ammonia. The rich liquid absorbs the heat of the ammonia to cool the ammonia. The rich liquid absorbs the heat of the ammonia to heat it up and then enters the decomposition tower 31. The ammonia discharged from the first heat exchanger 32 enters the cooling device 4, which is a cooler. After being cooled by the cooling device 4, it becomes liquid ammonia. The liquid ammonia enters the liquid ammonia storage tank 5 after being discharged from the cooling device 4. The concentration of liquid ammonia reaches 8%-10%.

[0038] Another aspect of the present invention provides a tail gas deamination method, which is implemented based on the tail gas deamination system described in any one of the above items, and the tail gas deamination method comprises: The absorbent is used to absorb ammonia in the tail gas, and the absorbent becomes a rich liquid after absorbing ammonia, and the tail gas that loses part of the ammonia becomes deammoniation tail gas; The washing liquid is used to absorb the ammonia in the deammoniation tail gas, and the filler is used to filter out the impurities in the deammoniation tail gas to form a secondary deammoniation tail gas, which is discharged after cooling and removing the droplets in the secondary deammoniation tail gas; Decomposing the rich liquid by using decomposition steam to release ammonia in the rich liquid; The ammonia gas is cooled to form liquid ammonia.

[0039] The tail gas deammonification system provided by the present invention comprises an absorption device that absorbs ammonia in the tail gas by an absorbent, and the absorbent becomes a rich liquid after absorbing ammonia. The tail gas that loses part of ammonia becomes a deammonified tail gas and enters a scrubber after being discharged from the absorption device. The scrubber absorbs ammonia in the deammonified tail gas again and filters out impurities in the deammonified tail gas. The deammonified tail gas becomes a secondary deammonified tail gas, and the secondary deammonified tail gas is cooled and the liquid droplets of the secondary deammonified tail gas are removed before the secondary deammonified tail gas is discharged. The rich liquid enters a decomposition device and decomposes ammonia in the rich liquid by decomposition steam. The released ammonia enters a cooling device after being discharged from the decomposition device. The cooling device cools the ammonia to cool the ammonia into liquid ammonia for storage. The tail gas deammonification system and method provided by the present invention first become a rich liquid after absorbing ammonia in the tail gas by an absorbent, and then decomposes the rich liquid by decomposition steam to release ammonia in the rich liquid, and cools the ammonia to liquefy the ammonia into liquid ammonia, which is convenient for storage, and solves the problem of difficulty in releasing ammonia in the products formed in the deammonification process in the prior art.

[0040] The optional implementation modes of the embodiments of the present invention are described in detail above in conjunction with the accompanying drawings. However, the embodiments of the present invention are not limited to the specific details in the above implementation modes. Within the technical concept of the embodiments of the present invention, various simple modifications can be made to the technical scheme of the embodiments of the present invention, and these simple modifications all belong to the protection scope of the embodiments of the present invention.

[0041] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. To avoid unnecessary repetition, the embodiments of the present invention will not further describe various possible combinations.

[0042] Those skilled in the art can understand that all or part of the steps in the above-mentioned embodiment method can be completed by instructing the relevant hardware through a program, and the program is stored in a storage medium, including a number of instructions to enable a single-chip microcomputer, a chip or a processor to execute all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk and other media that can store program codes.

[0043] In addition, various implementation modes of the embodiments of the present invention may be arbitrarily combined, and as long as they do not violate the concept of the embodiments of the present invention, they should also be regarded as the contents disclosed by the embodiments of the present invention.

Claims

1. A tail gas deamination system, characterized in that: The tail gas deamination system comprises: An absorption device (1) is used to absorb ammonia in the tail gas by using an absorbent. After the absorbent absorbs the ammonia, it becomes a rich liquid and enters the analysis device (3). The tail gas that loses some ammonia becomes a deammoniation tail gas and enters the scrubbing device (2); The scrubber (2) is used to absorb ammonia and impurities in the deammoniation tail gas to form secondary deammoniation tail gas, and to cool and remove droplets in the secondary deammoniation tail gas before discharging it; The desorption device (3) is used to desorb the rich liquid using desorption steam to release ammonia in the rich liquid. After the rich liquid releases the ammonia, it becomes a lean liquid and is transported to the absorption device (1); A cooling device (4) is used to cool the ammonia gas released from the analysis device (3) to form liquid ammonia.

2. The tail gas deamination system according to claim 1, characterized in that: The absorption device (1) comprises: an absorption tower (11), an absorbent supply assembly (12) and a plurality of first spray plates (13); A plurality of first spray plates (13) are arranged in layers in the absorption tower (11), and the absorbent is sprayed into the absorption tower (11) through the plurality of first spray plates (13); The absorbent supply assembly (12) is used to deliver absorbent to a plurality of first spray plates (13); The tail gas entering the absorption tower (11) can fully contact with the absorbent in the absorption tower (11). The absorbent absorbs ammonia in the tail gas and becomes a rich liquid, which is gathered at the bottom of the absorption tower (11). The tail gas that loses some ammonia becomes deammoniation tail gas and is discharged from the absorption tower (11).

3. The tail gas deamination system according to claim 2, characterized in that: A plurality of grids (14) are arranged at the bottom of the absorption tower (11), and impurities in the rich liquid are filtered out through the grids (14).

4. The tail gas deamination system according to claim 2, characterized in that: The spraying areas of the first spray plates (13) of adjacent layers in the absorption tower (11) are different.

5. The tail gas deamination system according to claim 2, characterized in that: The absorbent supply component (12) comprises: an inclined tube sedimentation tank (121), a liquid collecting tank (122), a separator (123) and a distribution component (124); The inclined tube sedimentation tank (121) is connected to the rich liquid outlet of the absorption tower (11) and is used to precipitate the rich liquid discharged from the rich liquid outlet so that the particulate impurities in the rich liquid are precipitated in the inclined tube sedimentation tank (121); The liquid collecting box (122) is connected to the inclined tube sedimentation tank (121) and the analytical device (3) and is used to recover the rich liquid and the lean liquid after precipitation to form a mixed liquid; A distribution component (124) is connected to the liquid collection tank (122) and a plurality of first spray plates (13), and the distribution component (124) is used to transport the mixed liquid in the liquid collection tank (122) as an absorbent to each first spray plate (13); The separator (123) is connected to the delivery component (124) and the analysis device (3) and is used to recover the mixed liquid overflowing from the delivery component (124) and to heat the mixed liquid so that the mixed liquid becomes a rich liquid again and is transported to the analysis device (3).

6. The tail gas deamination system according to claim 5, characterized in that: The absorption device (1) further comprises: A second spray plate (15) is arranged in the absorption tower (11) and is located below all the first spray plates (13); the second spray plate (15) is connected to the liquid collecting tank (122) and is used to spray the mixed liquid in the liquid collecting tank (122) as an absorbent into the absorption tower (11); The spraying area of ​​the second spray plate (15) is different from the spraying area of ​​the adjacent first spray plate (13).

7. The tail gas deamination system according to claim 5, characterized in that: The scrubbing device (2) comprises: a scrubbing tower (21), a first cooler (22), an electric demister (23) and a scrubbing liquid supply assembly (24); The washing liquid supply assembly (24) is used to supply washing liquid into the scrubbing tower (21); The scrubber (21) is connected to the absorption tower (11), and a filler is arranged in the scrubber (21). The scrubber (21) is used to absorb ammonia in the deammoniation tail gas using a scrubbing liquid and to filter out impurities in the deammoniation tail gas using the filler to form a secondary deammoniation tail gas; The first cooler (22) is used to cool the secondary deammoniation tail gas; The electric demister (23) is used to remove liquid droplets in the cooled secondary deammoniation tail gas.

8. The tail gas deamination system according to claim 5, characterized in that: The analysis device (3) comprises: an analysis tower (31) connected to the separator (123) and the liquid collecting tank (122), and used for analyzing the rich liquid from the separator (123) by using analysis steam to release ammonia in the rich liquid, and the rich liquid after the ammonia is released becomes a lean liquid and enters the liquid collecting tank (122).

9. The tail gas deamination system according to claim 8, characterized in that: The analysis device (3) further comprises: a first heat exchanger (32) disposed between the analysis tower (31) and the separator (123) and used for preliminarily heating the rich liquid from the separator (123) by utilizing the ammonia released by the analysis tower (31).

10. A tail gas deamination method, implemented based on the tail gas deamination system according to any one of claims 1 to 9, characterized in that: The tail gas deamination method comprises: The absorbent is used to absorb ammonia in the tail gas, and the absorbent becomes a rich liquid after absorbing ammonia, and the tail gas that loses part of the ammonia becomes deammoniation tail gas; The ammonia in the deammoniation tail gas is absorbed by the washing liquid, and the impurities in the deammoniation tail gas are filtered out by the filling material to form the secondary deammoniation tail gas, which is discharged after cooling and removing the droplets in the secondary deammoniation tail gas; Decomposing the rich liquid by using decomposition steam to release ammonia in the rich liquid; The ammonia gas is cooled to form liquid ammonia.

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