A device for diluting concentrated ammonia water for denitration

Abstract

The application discloses a kind of for diluting device of concentrated ammonia water for denitration, it is related to diluting device technical field, including mixing tank, water spraying component, heat preservation component, stirring assembly and dilution process control system, the water spraying component includes water tank, shunt tank, water pipe, four ammonia gas concentration detectors and spray head, wherein the connecting pipeline is provided between the water tank and mixing tank, the input of the shunt tank is communicated with the output of connecting pipeline, the output of the shunt tank is connected water pipe, the ammonia gas concentration detector is evenly separated and arranged on water pipe, the spray head is set on water pipe and corresponds with ammonia gas concentration detector one by one, the water pipe is erected in mixing tank inside, the heat preservation component is set to mixing tank periphery, the stirring assembly is set in mixing tank. The application can be according to the ammonia gas volatilized by using dilution water to capture concentrated ammonia water, improve the dilution quality of ammonia water.

Description

Technical Field

[0001] This invention relates to the field of dilution device technology, specifically to a device for diluting concentrated ammonia water for denitrification. Background Technology

[0002] To prevent excessive nitrogen oxide pollution from coal combustion in boilers, coal denitrification treatment is necessary. The world's mainstream denitrification processes are SCR and SNCR. Aside from the fact that SCR uses a catalyst, resulting in a lower reaction temperature than SNCR, these two processes are largely the same. However, considering both construction and operating costs, the investment in SCR is at least several times, and sometimes more than ten times, that of SNCR.

[0003] Cement plants generally use the "SNCR" method for denitrification. SNCR, or Selective Non-Catalytic Reduction, refers to the process of reducing nitrogen oxides in flue gas into harmless nitrogen and water by injecting a reducing agent within a suitable "temperature window" for the denitrification reaction, without the action of a catalyst. The reducing agent is the largest consumable item in SNCR denitrification. Urea or ammonia water is generally used as the reducing agent in cement denitrification. When using ammonia water, concentrated ammonia water is purchased and diluted with water to a certain concentration (around 10%) before use.

[0004] The ammonia concentration of concentrated ammonia solution is generally between 25% and 28%. Existing concentrated ammonia dilution processes involve injecting concentrated ammonia solution into a mixing tank, mixing it with a certain amount of dilution water, and then transferring it to a reaction vessel. Concentrated ammonia solution itself is highly volatile, and some of it will evaporate during the dilution process. Since the total amount of dilution water injected remains constant, the concentration of the diluted ammonia solution deviates from the ideal value. Summary of the Invention

[0005] The purpose of this invention is to provide a concentrated ammonia dilution device for denitrification, so as to solve the problems mentioned in the background art.

[0006] To solve the above-mentioned technical problems, the present invention provides the following technical solution: a concentrated ammonia dilution device for denitrification, comprising a mixing tank, a water spraying assembly, a heat preservation assembly, a stirring assembly, and a dilution process control system. The water spraying assembly includes a water tank, a distribution box, a water supply pipe, four ammonia concentration detectors, and nozzles. A connecting pipe is provided between the water tank and the mixing tank. The input end of the distribution box is connected to the output end of the connecting pipe, and the output end of the distribution box is connected to the water supply pipe. The ammonia concentration detectors are evenly spaced on the water supply pipe, suitable for detecting the ammonia concentration in the area. The nozzles are set on the water supply pipe and correspond one-to-one with the ammonia concentration detectors, suitable for spraying dilution water into the area. The water supply pipe is installed inside the mixing tank. The heat preservation assembly is set on the outer periphery of the mixing tank, suitable for controlling the temperature inside the mixing tank. The stirring assembly is set inside the mixing tank, suitable for stirring the ammonia water to achieve uniform dilution. The dilution process control system is signal-connected to the water spraying assembly, the heat preservation assembly, and the stirring assembly, suitable for regulating the dilution process.

[0007] Furthermore, the water supply pipe includes a ring main pipe and four branch pipes, wherein each branch pipe is led out from the ring main pipe, and the aforementioned ammonia concentration detector and nozzle are installed on the corresponding branch pipe.

[0008] Furthermore, the water tank has a built-in water pump for conveying water, and the output end of the diversion box is equipped with four diversion valves.

[0009] Furthermore, the annular main pipe is provided with four stop rings, dividing the annular main pipe into four sections. Each section corresponds to a branch pipe, and each section is provided with an inlet. Each inlet is connected to a corresponding diversion valve.

[0010] Furthermore, a solenoid valve is provided at the connection between the branch pipe and the annular main pipe.

[0011] Furthermore, a main valve and a flow meter are installed on the connecting pipeline, which are used to control the opening and closing of the connecting pipeline and to detect the water flow rate through the connecting pipeline, respectively.

[0012] Furthermore, the insulation component includes an insulation cover and several thermocouples, wherein the insulation cover is placed around the outer periphery of the mixing tank and leaves a certain space, and the thermocouples are inserted through the bottom of the insulation cover.

[0013] Furthermore, the heat insulation cover is made of heat-insulating material, and a heat exchange medium is filled between it and the mixing tank. Thermocouples are used to detect the temperature of the heat exchange medium, and the heat exchange medium can be, but is not limited to, water.

[0014] Furthermore, the stirring assembly includes a rotary motor, a rotating shaft, and a stirring paddle, wherein the rotating shaft is connected to the output end of the rotary motor, and the stirring paddle is fixed on the rotating shaft.

[0015] Furthermore, the combined tank is also equipped with an ammonia inlet pipe and an ammonia outlet pipe, and has movable support legs at the bottom.

[0016] Furthermore, the dilution process control system includes an information collection module, a data processing module, and a post-processing module. The information collection module includes a temperature acquisition unit and an ammonia concentration acquisition unit. The data processing module is adapted to analyze real-time temperature and ammonia concentration data. The post-processing module adjusts the water spraying component and the heat preservation component based on the analysis results of the data processing module to improve the quality of ammonia dilution.

[0017] Furthermore, the specific methods are as follows:

[0018] S1. Concentrated ammonia water input: Concentrated ammonia water is input into the mixing tank through an external conveying device via the ammonia water input pipe, and the input port is closed;

[0019] S2. Ammonia Concentration Detection: The ammonia concentration acquisition unit detects the ammonia concentration in the upper area of ​​the concentrated ammonia solution using four ammonia concentration detectors.

[0020] S3. Dilution water distribution: The data processing module distributes dilution water according to the ammonia concentration ratio of each zone.

[0021] S4. Dilution water injection: The nozzle injects the appropriate amount of water to the area it is spraying.

[0022] S5. Stirring: The stirring component is started to mix the dilution water and concentrated ammonia solution evenly;

[0023] S6. Output: After dilution, the ammonia water is sent out through the ammonia water output pipe.

[0024] During processes S1 to S6, the insulation component remains operational. The temperature acquisition unit uses thermocouples to monitor the real-time temperature of the heat exchange medium, ensuring that the temperature remains within the range of 0℃ to 10℃. The solubility of ammonia in water decreases rapidly with temperature changes. For example, at 0℃, one volume of water can dissolve 1000 volumes of ammonia, while at 20℃, one volume of water can dissolve 700 volumes of ammonia. The insulation component keeps the temperature of the mixing tank body within a low range, indirectly keeping the internal ammonia solution temperature within a low range. This prevents the concentrated ammonia solution from becoming more volatile due to high temperatures during dilution, thus avoiding the loss of a large amount of ammonia from the solution.

[0025] The dilution water distribution method in S3 is as follows: The ratio of ammonia concentration detected by the four ammonia concentration detectors is set as a:b:c:d. The total water volume that the annular main pipe can hold is V. Therefore, the maximum water volume that can be injected into each zone at one time is V / 4. Assuming that the value of a is the largest among the four ratios, the zone corresponding to value a is filled with V / 4 water. Other zones are divided according to the ratio. For example, the area containing value b is injected with a water volume of... * The water injection volume in the area where value c is located is * The water injection volume in the area where the d value is located is * After one spraying is completed, the ammonia concentration detector will re-detect the ammonia concentration in each zone and use this as a benchmark to adjust the proportion of water to be sprayed in the next batch until all the dilution water is injected. By injecting dilution water in batches and adjusting the amount of water sprayed according to the ammonia concentration in different areas, the dilution water can be used to capture the volatilized ammonia in the space and improve the final dilution quality.

[0026] Compared with the prior art, the beneficial effects achieved by the present invention are as follows: by setting up a water spraying component and a dilution process control system, the ammonia concentration in each zone above the concentrated ammonia water can be detected, and the dilution water can be distributed according to the concentration ratio between different zones, so as to make reasonable use of the dilution water to dissolve the ammonia gas volatilized in the air and improve the dilution quality; by setting up a heat preservation component, the temperature of the mixing tank can be maintained at a low temperature to reduce the volatility of the ammonia water inside. Attached Figure Description

[0027] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used in conjunction with embodiments of the invention to explain the invention and do not constitute a limitation thereof. In the drawings:

[0028] Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0029] Figure 2 This is a cross-sectional view of the present invention;

[0030] Figure 3 This is a schematic diagram of the water supply pipe of the present invention;

[0031] Figure 4 This is a schematic diagram of the water spray assembly of the present invention;

[0032] In the diagram: 1. Mixing tank; 11. Ammonia water inlet pipe; 12. Ammonia water outlet pipe; 13. Support leg; 2. Spray assembly; 21. Water tank; 211. Water pump; 22. Diverter box; 221. Diverter valve; 23. Water supply pipe; 231. Ring main pipe; 2311. Stop ring; 2312. Inlet; 232. Branch pipe; 24. Ammonia concentration detector; 25. Nozzle; 3. Insulation assembly; 31. Insulation cover; 32. Thermocouple; 4. Stirring assembly; 41. Rotary motor; 42. Shaft; 43. Stirring paddle; 5. Connecting pipeline; 51. Main valve; 52. Flow meter; 6. Solenoid valve. Implementation

[0033] The following detailed, non-limiting description of the technical solution of the present invention, in conjunction with preferred embodiments and accompanying drawings, is provided. Obviously, the described embodiments are merely some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0034] Please see Figure 1-4 This invention provides a technical solution: a concentrated ammonia dilution device for denitrification, comprising a mixing tank 1, a water spraying assembly 2, a heat preservation assembly 3, a stirring assembly 4, and a dilution process control system. The water spraying assembly 2 includes a water tank 21, a distribution box 22, a water supply pipe 23, four ammonia concentration detectors 24, and nozzles 25. A connecting pipe 5 is provided between the water tank 21 and the mixing tank 1. The input end of the distribution box 22 is connected to the output end of the connecting pipe 5, and the output end of the distribution box 22 is connected to the water supply pipe 23. The ammonia concentration detectors 24 are evenly spaced... The system is installed on the water supply pipe 23 and is suitable for detecting the ammonia concentration in the area. The nozzle 25 is installed on the water supply pipe 23 and corresponds one-to-one with the ammonia concentration detector 24. It is suitable for spraying dilution water into the area. The water supply pipe 23 is installed inside the mixing tank 1. The heat preservation component 3 is installed on the outer periphery of the mixing tank 1 and is suitable for controlling the temperature inside the mixing tank 1. The stirring component 4 is installed inside the mixing tank 1 and is suitable for stirring the ammonia water to make the dilution uniform. The dilution process control system is connected to the water spray component 2, the heat preservation component 3 and the stirring component 4 and is suitable for regulating the dilution process.

[0035] The water supply pipe 23 includes a ring main pipe 231 and four branch pipes 232, wherein each branch pipe 232 is led out from the ring main pipe 231, and the aforementioned ammonia concentration detector 24 and nozzle 25 are installed on the corresponding branch pipe 232.

[0036] The water tank 21 has a built-in water pump 211 for conveying water, and the output end of the diversion box 22 is equipped with four diversion valves 221.

[0037] The annular main pipe 231 is provided with four stop rings 2311, which divide the annular main pipe 231 into four sections. Each section corresponds to a branch pipe 232, and each section is provided with an inlet 2312. Each inlet 2312 is connected to the corresponding diversion valve 221.

[0038] A solenoid valve 6 is installed at the connection between the branch pipe 232 and the annular main pipe 231.

[0039] A main valve 51 and a flow meter 52 are installed on the connecting pipe 5, which are used to control the opening and closing of the connecting pipe 5 and to detect the water flow rate through the connecting pipe 5, respectively.

[0040] In actual operation, the dilution water is stored in the water tank 21 and pumped to the annular main pipe 231 by the water pump 211. After passing through the branch pipe 232, it is finally sprayed out by the nozzle 25. The amount of water sprayed out by each nozzle 25 is determined by the ammonia concentration detected by the corresponding ammonia concentration detector 24. The total amount of dilution water remains unchanged. Specifically, the dilution water in the four zones on the annular main pipe 231 is sprayed in sequence. When a zone starts to deliver dilution water, the diversion valve 221 corresponding to that zone is opened, and the diversion valves 221 corresponding to other zones are closed.

[0041] The insulation component 3 includes an insulation cover 31 and several thermocouples 32. The insulation cover 31 covers the outer periphery of the mixing tank 1 and leaves a certain space. The thermocouples 32 pass through the bottom of the insulation cover 31.

[0042] It should be noted that: the heat insulation cover 31 is made of heat insulation material, and a heat exchange medium is filled between it and the mixing tank 1. Thermocouple 32 is used to detect the temperature of the heat exchange medium. The heat exchange medium can be, but is not limited to, water.

[0043] The stirring assembly 4 includes a rotary motor 41, a rotating shaft 42, and a stirring paddle 43, wherein the rotating shaft 42 is connected to the output end of the rotary motor 41, and the stirring paddle 43 is fixed on the rotating shaft 42.

[0044] The mixing tank 1 is also equipped with an ammonia water inlet pipe 11 and an ammonia water outlet pipe 12, and has movable support legs 13 at the bottom.

[0045] The dilution process control system includes an information collection module, a data processing module, and a post-processing module. The information collection module includes a temperature acquisition unit and an ammonia concentration acquisition unit. The data processing module is suitable for analyzing real-time temperature and ammonia concentration data. The post-processing module adjusts the water spray component 2 and the heat preservation component 3 based on the analysis results of the data processing module to improve the quality of ammonia dilution.

[0046] The specific implementation method is as follows:

[0047] S1. Concentrated ammonia water input: Concentrated ammonia water is input into the mixing tank 1 through the ammonia water input pipe 11 via an external conveying device, and the input port is closed;

[0048] S2. Ammonia Concentration Detection: The ammonia concentration acquisition unit detects the ammonia concentration in the upper area of ​​the concentrated ammonia solution using four ammonia concentration detectors 24.

[0049] S3. Dilution water distribution: The data processing module distributes dilution water according to the ammonia concentration ratio of each zone.

[0050] S4. Dilution water injection: Nozzle 25 is the amount of water mixed for the area to be sprayed;

[0051] S5. Stirring: Stirring component 4 is started to mix the dilution water and concentrated ammonia water evenly;

[0052] S6. Output: After dilution, the ammonia water is sent out through the ammonia water output pipe 12.

[0053] Specifically, during processes S1 to S6, the insulation component 3 is always in operation. The temperature acquisition unit detects the real-time temperature of the heat exchange medium through thermocouple 32, ensuring that the temperature of the heat exchange medium is within the range of 0℃ to 10℃. The solubility of ammonia in water decreases rapidly with temperature changes. For example, at 0℃, one volume of water can dissolve 1000 volumes of ammonia, while at 20℃, one volume of water can dissolve 700 volumes of ammonia. The insulation component 3 keeps the temperature of the mixing tank 1 within a low range, indirectly keeping the temperature of the ammonia solution inside within a low range. This avoids the increased volatility of concentrated ammonia solution due to high temperatures during the dilution process, preventing a large amount of ammonia from being lost from the ammonia solution.

[0054] The dilution water distribution method in S3 is as follows: The ratio of ammonia concentration detected by the four ammonia concentration detectors 24 is set as a:b:c:d. The total water volume that the annular main pipe 231 can hold is V. Therefore, the maximum water volume that can be injected into each zone at one time is V / 4. Assuming that the value of a is the largest among the four ratios, the zone corresponding to the value of a is filled with V / 4 water. Other zones are divided according to the ratio. For example, the area where the value of b is located is injected with a water volume of... * The water injection volume in the area where value c is located is * The water injection volume in the area where the d value is located is * After one spraying is completed, the ammonia concentration detector 24 will detect the ammonia concentration in each zone again, and use this as a benchmark to adjust the proportion of the next batch of sprayed water until all the dilution water is injected. By injecting dilution water in batches, the spray water volume can be controlled according to the ammonia concentration in different areas, and the dilution water can be used to capture the volatilized ammonia in the space, thereby improving the final dilution quality.

[0055] In the description of this invention, it should be understood that the terms "upper", "lower", "front", "rear", "left", "right", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this invention, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0056] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features, and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A device for diluting concentrated ammonia water for denitrification, characterized in that: include: The system includes a mixing tank (1), a water spray assembly (2), a heat preservation assembly (3), a stirring assembly (4), and a dilution process control system. The water spray assembly (2) includes a water tank (21), a distribution box (22), a water supply pipe (23), four ammonia concentration detectors (24), and a nozzle (25). A connecting pipe (5) is provided between the water tank (21) and the mixing tank (1). The input end of the distribution box (22) is connected to the output end of the connecting pipe (5), and the output end of the distribution box (22) is connected to the water supply pipe (23). The ammonia concentration detectors (24) are evenly spaced on the water supply pipe (23) and are suitable for detecting ammonia in the area. The nozzle (25) is set on the water supply pipe (23) and corresponds one-to-one with the ammonia concentration detector (24), which is suitable for spraying dilution water into the area. The water supply pipe (23) is set inside the mixing tank (1). The heat preservation component (3) is set on the outer periphery of the mixing tank (1), which is suitable for controlling the temperature inside the mixing tank (1). The stirring component (4) is set inside the mixing tank (1), which is suitable for stirring the ammonia water to make the dilution uniform. The dilution process control system is connected to the water spray component (2), the heat preservation component (3) and the stirring component (4) by signal, which is suitable for regulating the dilution process and distributing the dilution water according to the concentration ratio between different zones.

2. The concentrated ammonia dilution device for denitrification according to claim 1, characterized in that: The water supply pipe (23) includes a ring main pipe (231) and four branch pipes (232), wherein each branch pipe (232) is led out from the ring main pipe (231), and the ammonia concentration detector (24) and the nozzle (25) are installed on the corresponding branch pipe (232).

3. The concentrated ammonia dilution device for denitrification according to claim 2, characterized in that: The water tank (21) has a built-in water pump (211) for conveying water, and the output end of the diversion box (22) is equipped with four diversion valves (221).

4. The concentrated ammonia dilution device for denitrification according to claim 3, characterized in that: The annular main pipe (231) is provided with four stop rings (2311), which divide the annular main pipe (231) into four sections. Each section corresponds to a branch pipe (232), and each section is provided with an inlet (2312). Each inlet (2312) is connected to the corresponding diversion valve (221).

5. The concentrated ammonia dilution device for denitrification according to claim 4, characterized in that: A solenoid valve (6) is provided at the connection between the branch pipe (232) and the annular main pipe (231).

6. The concentrated ammonia dilution device for denitrification according to claim 5, characterized in that: The insulation component (3) includes an insulation cover (31) and several thermocouples (32), wherein the insulation cover (31) covers the outer periphery of the mixing tank (1) and leaves a certain space, and the thermocouples (32) pass through the bottom of the insulation cover (31); The heat insulation cover (31) is made of heat insulation material and is filled with heat exchange medium between itself and the mixing tank (1). The thermocouple (32) is used to detect the temperature of the heat exchange medium, and water is selected as the heat exchange medium.

7. The concentrated ammonia dilution device for denitrification according to claim 6, characterized in that: The mixing tank (1) is also equipped with an ammonia water inlet pipe (11) and an ammonia water outlet pipe (12), and has movable support feet (13) at the bottom.

8. The concentrated ammonia dilution device for denitrification according to claim 7, characterized in that: The dilution process control system includes an information collection module, a data processing module, and a post-processing module. The information collection module includes a temperature acquisition unit and an ammonia concentration acquisition unit. The data processing module is suitable for analyzing real-time temperature and ammonia concentration data. The post-processing module adjusts the water spray component (2) and the heat preservation component (3) according to the analysis results of the data processing module to improve the quality of ammonia dilution.

9. The method of using the concentrated ammonia dilution device for denitrification according to claim 8, characterized in that: The specific method is as follows: S1, concentrated ammonia water input: concentrated ammonia water is input into the mixing tank (1) through the ammonia water input pipe (11) via an external conveying device, and the input port is closed; S2, Ammonia Concentration Detection: The ammonia concentration acquisition unit detects the ammonia concentration in the upper area of ​​the concentrated ammonia water using four ammonia concentration detectors (24); S3. Dilution water distribution: The data processing module distributes dilution water according to the ammonia concentration ratio of each zone. S4, Dilution water injection: The nozzle (25) sprays the amount of water mixed in the area; S5. Stirring: Start the stirring component (4) to mix the dilution water and concentrated ammonia water evenly; S6. Output: After dilution, the ammonia water is sent out through the ammonia water output pipe (12).

10. The method of using the concentrated ammonia dilution device for denitrification according to claim 9, characterized in that: The dilution water distribution method in S3 is as follows: The ratio of ammonia concentration detected by the four ammonia concentration detectors (24) is set as a:b:c:d. The total volume of water that the annular main pipe (231) can hold is V. Therefore, the maximum amount of water that can be injected into each zone at one time is V / 4. Assuming that the value of a is the largest among the four ratios, the zone corresponding to the value of a is filled with V / 4 water. Other zones are divided according to the ratio, and the area where the value of b is located is injected with water as follows: * The water injection volume in the area where value c is located is * The water injection volume in the area where the d value is located is * After one spraying is completed, the ammonia concentration detector (24) will detect the ammonia concentration in each zone again, and adjust the ratio of the next batch of sprayed water based on this, until all the dilution water is injected. By injecting dilution water in batches, the spray water volume can be controlled according to the ammonia concentration in different areas, and the dilution water can be used to capture the volatilized ammonia in the space, thereby improving the final dilution quality.

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