Flue gas bypass ammonia production coupling wide-load denitration device
Through flue gas bypass ammonia production technology, pyrolyzed urea to produce ammonia, combined with the design of ammonia distributor, the problems of complex process and high cost in the traditional liquid ammonia conversion process are solved, and efficient and safe wide-load denitrification effect is achieved.
Patent Information
- Application Number
- CN202411871704.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-18
- Publication Date
- 2025-03-25
AI Technical Summary
During the traditional liquid ammonia conversion process, the hydrolysis process has huge investment and complex process equipment, resulting in low safety and efficiency of denitrification in power plants.
The flue gas bypass ammonia-generating coupled wide-load denitrification device is adopted to pyrolyze urea through bypass flue gas to generate ammonia gas, replace liquid ammonia technology, and combine the ammonia distributor to uniformly spray it into the SCR inlet flue pipeline to optimize the ammonia spraying process.
It reduces the investment and operating costs of urea ammonia production, improves denitrification efficiency and load adaptability, enhances the safety and efficiency of denitrification in power plants, and reduces the cost of later transformation.
Smart Images
Figure CN119687467A_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the field of boiler denitration, and in particular to a flue gas bypass ammonia production coupled with a wide load denitration device. Background Art
[0002] Nitrogen oxides are the main component of air pollution. Denitrification transformation of power plants is an important measure to reduce nitrogen oxide emissions and protect the environment.
[0003] Among the related technologies, converting liquid ammonia to urea is also the current theme of denitrification transformation in power plants. Liquid ammonia to urea usually uses urea hydrolysis technology to replace the original liquid ammonia technology. However, the hydrolysis process has the problems of huge investment, complex process equipment, insufficient safety and high operating costs. Summary of the invention
[0004] The present application provides a flue gas bypass ammonia production coupled with a wide load denitrification device, which can solve the problems of huge investment and complex process equipment in the hydrolysis process in the traditional liquid ammonia to urea process, and improve the safety and efficiency of power plant denitrification.
[0005] The present application provides a flue gas bypass ammonia production coupled with a wide load denitrification device, which includes:
[0006] A boiler, wherein the boiler is connected to an SCR inlet flue pipeline, and the SCR inlet flue pipeline is connected to an SCR reactor;
[0007] A bypass flue pipe, one end of which is connected to the boiler, and the other end of which is connected to an ammonia production reaction chamber, wherein a urea injection device is installed in the ammonia production reaction chamber;
[0008] An ammonia distributor, one end of which is communicated with the ammonia production reaction chamber, and the other end of which is communicated with the side wall of the SCR inlet flue pipe.
[0009] In one embodiment, the urea injection device comprises:
[0010] A plurality of urea spray guns are installed on the bypass flue pipe in an annularly spaced manner.
[0011] In one embodiment, a plug-in door is installed in the bypass flue pipe.
[0012] In one embodiment, an adjusting door is installed in the bypass flue pipe, and along the direction of the flue gas path in the bypass flue pipe, the adjusting door is located in front of the plug-in door.
[0013] In one embodiment, the ammonia dispenser comprises:
[0014] A connecting trunk pipeline, one end of which is connected to the ammonia production reaction chamber, and the other end of which is connected to the side wall of the SCR inlet flue pipeline, and the connecting trunk pipeline is installed with a regulating valve and a flow meter.
[0015] In one embodiment, the ammonia dispenser comprises:
[0016] A connecting trunk pipeline, one end of which is connected to the ammonia production reaction chamber, and the other end of which is connected to multiple connecting branch pipelines, each of which is installed with a regulating valve and a flow meter, and each of which is connected to the side wall of the SCR inlet flue pipeline.
[0017] In one embodiment, the connecting trunk pipeline is roughly funnel-shaped, the narrow end of the connecting trunk pipeline is connected to the ammonia production reaction chamber, and the wide end thereof is connected to the plurality of connecting branch pipelines.
[0018] In one embodiment, a plurality of guide plates are disposed in the connecting main pipeline, and the plurality of guide plates correspond one-to-one to the plurality of connecting branch pipelines, and guide the ammonia gas into the corresponding connecting branch pipelines.
[0019] In one embodiment, a zoned nitrogen and oxygen sensor is installed at the inlet and outlet of the SCR reactor respectively.
[0020] In one embodiment, the flue gas introduction point of the bypass flue pipe is located at the outlet of the turning chamber of the boiler, the inlet of the superheater of the boiler, or the inlet of the economizer of the boiler.
[0021] The beneficial effects brought by the technical solution provided in the embodiments of the present application include:
[0022] (1) Utilize the heat of the bypass flue gas to pyrolyze urea and decompose urea into ammonia, replacing the original liquid ammonia technology and eliminating the safety hazards caused by liquid ammonia. Through the design of the bypass flue pipe and the ammonia production reaction chamber, wide-load denitrification is achieved, the denitrification efficiency is improved, and the load adaptability is enhanced. Ammonia is evenly sprayed into the SCR inlet flue pipe through an ammonia distributor, which optimizes the ammonia spraying process and further improves the denitrification efficiency. The urea bypass ammonia production technology uses high-temperature flue gas to directly decompose the urea solution. Compared with the traditional pyrolysis using electricity and hydrolysis using steam, it greatly reduces the investment cost and operating cost of urea ammonia production. At the same time, the higher flue gas temperature improves the urea decomposition efficiency;
[0023] (2) The bypass ammonia production process outlet adopts a multi-branch distribution device, which can cooperate to realize the zoned ammonia injection (ammonia injection optimization) modification of the boiler, so that the boiler is exempted from the ammonia injection grid modification, reducing the cost of the subsequent ammonia injection optimization modification. At the same time, the bypass flue gas increases the temperature of the SCR reactor inlet, solves the problem of insufficient catalyst inlet temperature during the low-load operation of the boiler, and ensures the safety of the catalyst under low load;
[0024] (3) This technical combination solves the problems of large investment, complex process equipment, insufficient safety, high operating costs, etc. in the hydrolysis and pyrolysis processes commonly used to convert liquid ammonia to urea. At the same time, it enables the denitrification system to have the function of zoned ammonia injection, which saves the power plant boiler from further ammonia injection optimization modification, improves the safety and efficiency of power plant denitrification, and saves a lot of investment costs and operating costs. BRIEF DESCRIPTION OF THE DRAWINGS
[0025] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.
[0026] Figure 1 This is a schematic diagram of the structure of a flue gas bypass ammonia production coupled with a wide load denitrification device;
[0027] Figure 2 This is a schematic diagram of the structure of the ammonia distributor.
[0028] In the figure: 1. boiler; 2. SCR inlet flue pipe; 3. SCR reactor; 4. bypass flue pipe; 5. ammonia production reaction chamber; 6. urea injection device; 7. plug-in door; 8. regulating door; 9. ammonia distributor; 91. connecting main pipeline; 92. regulating valve; 93. connecting branch pipeline; 94. flow meter. DETAILED DESCRIPTION
[0029] In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.
[0030] The embodiment of the present application provides a flue gas bypass ammonia production coupled with a wide load denitrification device, which can solve the problems of huge investment and complex process equipment in the hydrolysis process in the traditional liquid ammonia to urea process, and improve the safety and efficiency of power plant denitrification.
[0031] like Figure 1 As shown, an embodiment of the present application provides a flue gas bypass ammonia production coupled wide-load denitrification device, which includes: a boiler 1, the boiler 1 is connected to an SCR inlet flue pipeline 2, and the SCR inlet flue pipeline 2 is connected to an SCR reactor 3; a bypass flue pipe 4, one end of the bypass flue pipe 4 is connected to the boiler 1, and the other end thereof is connected to an ammonia production reaction chamber 5, and the ammonia production reaction chamber 5 is equipped with a urea injection device 6; an ammonia distributor 9, one end of the ammonia distributor 9 is connected to the ammonia production reaction chamber, and the other end thereof is connected to the side wall of the SCR inlet flue pipeline 2.
[0032] In this embodiment, the boiler 1 serves as the main heat source and flue gas generating device. The SCR inlet flue pipe 2 connects the boiler 1 and the SCR reactor 3, and is used to transport the flue gas to the SCR reactor for denitration treatment. The SCR reactor 3 is the core denitration device, which reduces the nitrogen oxides in the flue gas to nitrogen and water through a catalyst. The bypass flue pipe 4 is connected to the boiler 1, and is used to introduce part of the flue gas into the ammonia production reaction chamber for urea pyrolysis to produce ammonia. The ammonia production reaction chamber 5 is equipped with a urea injection device 6, which is used to pyrolyze urea to produce ammonia. The urea injection device 6 injects urea into the ammonia production reaction chamber 5 for pyrolysis reaction. One end of the ammonia distributor 9 is connected to the ammonia production reaction chamber 5, and the other end is connected to the side wall of the SCR inlet flue pipe 2, which is used to evenly distribute the generated ammonia to the SCR inlet flue pipe 2. Wide load denitration: Through the design of the bypass flue pipe 4 and the ammonia production reaction chamber 5, the device can effectively perform denitration treatment under different loads, thereby improving the denitration efficiency and adaptability. Urea pyrolysis to produce ammonia: The urea injection device 6 is used to spray urea into the ammonia production reaction chamber 5 for pyrolysis, and ammonia is produced as a denitrification agent, which reduces the operating cost. Uniform distribution of ammonia: The ammonia produced is evenly distributed to the SCR inlet flue pipe 2 through the ammonia distributor 9, which improves the denitrification efficiency and the utilization rate of the catalyst. In summary, the flue gas bypass ammonia production coupled with a wide load denitrification device has the advantages of high efficiency, economy, strong adaptability, etc., and is suitable for denitrification treatment of boilers of various sizes.
[0033] Specifically, the three technical improvements of boiler wide-load denitrification, liquid ammonia conversion to urea, and precise ammonia injection are coupled into one, which saves a lot of initial investment while streamlining the process and equipment; the flue gas bypass ammonia production technology uses the heat of the flue gas itself as the heat source for urea production. Compared with the use of steam for urea hydrolysis and electricity as the pyrolysis heat source for conventional pyrolysis technology, its energy-saving effect is very significant and the operating cost is low.
[0034] In one embodiment, Figure 1 As shown, the urea injection device 6 includes: a plurality of urea spray guns, and the plurality of urea spray guns are circumferentially spaced and installed on the bypass flue pipe 4 .
[0035] In this embodiment, a plurality of urea spray guns are installed in a distributed manner on the bypass flue pipe 4 in an annular spacing manner to ensure that urea can be uniformly sprayed into the ammonia production reaction chamber 5. Each urea spray gun must be firmly mounted on the bypass flue pipe 4 and ensure reliable connection with the urea supply system so that urea can be accurately and stably sprayed when needed. As the core component of the urea injection device 6, the urea spray gun is responsible for spraying urea into the ammonia production reaction chamber 5 in a mist form. By distributing a plurality of urea spray guns in an annular spacing manner, uniform urea injection can be achieved, thereby improving the pyrolysis efficiency and the quality of ammonia generation. This embodiment ensures the uniformity and stability of urea injection and provides a reliable source of ammonia for the subsequent denitration reaction.
[0036] In one embodiment, a plug-in door 7 is installed in the bypass flue pipe 4 .
[0037] In this embodiment, the plug-in door 7 should be able to withstand the working temperature of the flue gas, without damage, adhesion, curling or leakage, and should be designed according to the maximum design positive and negative pressure values. The plug-in door 7 and its drive device should be able to withstand the corrosion of the working medium under operating conditions. At the design pressure and design temperature, the plug-in door 7 should have good airtightness to facilitate maintenance work on the flue isolation section. According to actual needs, the plug-in door 7 can be made of stainless steel to adapt to high temperature and corrosive environments. This implementation method ensures the reliability and durability of the plug-in door 7 in the bypass flue pipe 4, and meets the needs of flue gas isolation and maintenance work.
[0038] In one embodiment, an adjusting door 8 is installed in the bypass flue pipe 4 , and along the direction of the flue gas path in the bypass flue pipe 4 , the adjusting door 8 is located in front of the plug-in door 7 .
[0039] In this embodiment, in the bypass flue pipe 4, along the flue gas path direction, the regulating door 8 is located in front of the plug-in door 7. The regulating door 8 can flexibly control the flue gas flow in the bypass flue pipe 4. By regulating the regulating door 8, the working efficiency of the denitration system can be optimized to ensure that ultra-low NOx emissions can be achieved even under low load conditions. This embodiment improves the flexibility and controllability of the flue gas flow in the bypass flue pipe 4 by adding the regulating door 8, which helps to optimize the working efficiency of the denitration system and ensure that the emission of environmental protection indicators meets the standards.
[0040] In one embodiment, the ammonia distributor 9 includes: a connecting main pipeline 91, one end of which is connected to the ammonia production reaction chamber 5, and the other end of which is connected to the side wall of the SCR inlet flue pipeline 2, and the connecting main pipeline 91 is installed with a regulating valve 92 and a flow meter 94.
[0041] In this embodiment, the connecting trunk pipeline 91 is used as the core component of the ammonia distributor 9, and the connecting trunk pipeline 91 is responsible for transporting the ammonia generated in the ammonia production reaction chamber 5 to the SCR inlet flue pipeline 2. The regulating valve 92 is installed on the connecting trunk pipeline 91 to adjust the flow rate of ammonia and ensure that ammonia can enter the SCR inlet flue pipeline 2 according to the set ratio and flow rate. The flow meter 94 is also installed on the connecting trunk pipeline 91 to monitor the flow rate of ammonia in real time and provide accurate data support for the regulation of the regulating valve 92. One end of the connecting trunk pipeline 91 is connected to the ammonia production reaction chamber 5 to ensure that the ammonia generated in the ammonia production reaction chamber 5 can be received. The other end of the connecting trunk pipeline 91 is connected to the side wall of the SCR inlet flue pipeline 2 to ensure that ammonia can smoothly enter the SCR inlet flue pipeline 2. The ammonia distributor 9 realizes accurate distribution and flow control of ammonia through the coordinated work of the connecting trunk pipeline 91, the regulating valve 92 and the flow meter 94. The regulating valve 92 can adjust the flow rate of ammonia according to actual needs to ensure that the mixing ratio of ammonia and flue gas reaches the optimal state, thereby improving the denitration efficiency. The flow meter 94 monitors the flow rate of ammonia in real time, providing accurate data support for operators, which helps to find and solve problems in time. This implementation method ensures the accuracy and reliability of the ammonia distributor 9 and provides a strong guarantee for the stable operation of the denitration system.
[0042] In one embodiment, Figure 2 As shown, the ammonia distributor 9 includes: a connecting main pipeline 91, one end of which is connected to the ammonia production reaction chamber 5, and the other end of which is connected to multiple connecting branch pipelines 93, each of which is equipped with a regulating valve 92 and a flow meter 94, and each of the connecting branch pipelines 93 is connected to the side wall of the SCR inlet flue pipeline 2.
[0043] In this embodiment, the connecting trunk pipeline 91 is used as a transport channel for ammonia. One end is connected to the ammonia production reaction chamber 5 to receive ammonia, and the other end is divided into multiple connecting branch pipelines 93, each branch is connected to the side wall of the SCR inlet flue pipeline 2. The regulating valve 92 is used to adjust the flow rate of ammonia in each branch pipeline. The flow meter 94 monitors the flow rate of ammonia in each branch pipeline in real time. This embodiment realizes the precise distribution and flow monitoring of ammonia through multiple connecting branch pipelines 93, ensuring the stable operation of the denitrification system.
[0044] In one embodiment, Figure 2 As shown, the connecting trunk pipeline 91 is roughly funnel-shaped, and the narrow end of the connecting trunk pipeline 91 is connected to the ammonia production reaction chamber 5, and the wide end thereof is connected to the plurality of connecting branch pipelines 93.
[0045] In this embodiment, the connecting trunk pipeline 91 is roughly funnel-shaped, and this design helps to evenly distribute and flow ammonia in the pipeline. The narrow end is connected to the ammonia production reaction chamber 5 as the inlet of ammonia. The wide end is connected to multiple connecting branch pipelines 93 as the distribution outlet of ammonia. The funnel-shaped design allows ammonia to gradually diffuse and evenly distribute to each connecting branch pipeline 93 after entering the connecting trunk pipeline 91 from the ammonia production reaction chamber 5. This design helps to reduce the eddy current and turbulence of ammonia in the pipeline, reduce energy consumption, and improve the distribution efficiency of ammonia. This embodiment optimizes the distribution effect of ammonia through the design of the connecting trunk pipeline 91 in a funnel shape, ensuring the stable operation and high efficiency of the denitrification system.
[0046] In one embodiment, a plurality of guide plates are disposed in the connecting main pipeline 91 , and the plurality of guide plates correspond one-to-one to the plurality of connecting branch pipelines 93 , and guide the ammonia gas into the corresponding connecting branch pipelines 93 .
[0047] In this embodiment, a plurality of guide plates are provided in the connecting trunk pipeline 91. These guide plates correspond one to one with the plurality of connecting branch pipelines 93. The function of the guide plates is to effectively guide the ammonia gas into the corresponding connecting branch pipelines 93. Through the above design, it can be ensured that the ammonia gas can flow into each connecting branch pipeline 93 evenly and smoothly in the connecting trunk pipeline 91, thereby further improving the distribution efficiency and heat dissipation effect of the ammonia distributor 9. This design helps to optimize the overall performance and ensure that it can maintain stability and efficiency during operation.
[0048] In one embodiment, the inlet and outlet of the SCR reactor 3 are respectively equipped with zoned nitrogen and oxygen sensors.
[0049] In this embodiment, the imported nitrogen oxide sensor is installed in the inlet area of the SCR reactor 3 to detect the concentration of nitrogen oxides in the exhaust gas entering the reactor. The exported nitrogen oxide sensor is installed in the outlet area of the SCR reactor 3 to detect the remaining concentration of nitrogen oxides in the treated exhaust gas. The nitrogen oxide sensor uploads the detected concentration data to the controller. The controller controls the urea injection amount of the SCR system based on these data to ensure the effective removal of nitrogen oxides. By monitoring the inlet and outlet nitrogen oxide concentrations, the processing efficiency of the SCR reactor 3 can be evaluated, and the operating parameters can be adjusted in time to optimize the performance. The nitrogen oxide sensor is one of the key components for achieving precise control and effective emission reduction of the SCR system. By setting the inlet and outlet nitrogen oxide sensors, it can be ensured that the SCR reactor 3 achieves the best effect when treating nitrogen oxides.
[0050] In one embodiment, the flue gas introduction point of the bypass flue pipe 4 is located at the outlet of the turning chamber of the boiler 1 or the inlet of the superheater of the boiler 1 or the inlet of the economizer of the boiler 1 .
[0051] In this embodiment, the flue gas introduction point of the bypass flue pipe 4 is carefully selected at a key position of the boiler 1 to improve the efficiency and performance of the overall system. Specifically, this introduction point can be located at one of the following three positions: the outlet of the turning chamber of the boiler 1: the turning chamber is an important node for the flow of flue gas inside the boiler. Selecting this as the introduction point can ensure that the bypass flue pipe 4 can capture stable and moderately heated flue gas. It helps to balance the flow of flue gas inside the boiler and reduce thermal stress. The superheater inlet of the boiler 1: the superheater is a key component in the boiler for further heating steam. Selecting this as the introduction point can ensure that the flue gas captured by the bypass flue pipe 4 has a higher temperature, which is conducive to the subsequent pyrolysis reaction and denitrification process. At the same time, this also helps to optimize the working conditions of the superheater and improve its efficiency. The economizer inlet of the boiler 1: the economizer is an important component in the boiler for preheating feed water. Selecting this as the introduction point can ensure that the flue gas captured by the bypass flue pipe 4 has a moderate temperature and flow rate. This helps to optimize the working conditions of the economizer, improve its preheating efficiency, and reduce heat loss. In summary, by reasonably selecting the flue gas introduction point of the bypass flue pipe 4, the working conditions of the boiler 1 and the entire denitrification system can be optimized, and the efficiency and performance of the system can be improved. This design helps to reduce pollutant emissions, protect the environment, and meet strict environmental protection standards.
[0052] In one embodiment, the ammonia outlet point of the ammonia distributor 9 is located between the air preheater of the boiler 1 and the SCR inlet flue pipe 2 .
[0053] In this embodiment, the ammonia outlet point of the ammonia distributor 9 is cleverly set between the air preheater of the boiler 1 and the SCR inlet flue pipe 2. Setting the ammonia outlet point at this position can ensure that the ammonia is fully mixed with the flue gas before entering the SCR reactor 3. This helps to improve the utilization rate of ammonia in the SCR reactor 3, thereby more effectively reducing the nitrogen oxide content in the flue gas. Sufficient mixing of ammonia and flue gas helps to form a more uniform ammonia distribution in the SCR reactor 3. This ensures that the nitrogen oxides in the flue gas are fully in contact with ammonia, thereby improving the denitrification efficiency. By optimizing the mixing of ammonia and flue gas, the escape of unreacted ammonia into the atmosphere can be reduced. This helps to reduce the ammonia escape rate, thereby reducing the impact on the environment. Setting the ammonia outlet point between the air preheater and the SCR inlet flue pipe 2 can simplify the layout of the denitrification system. This helps to reduce system complexity and improve system reliability and maintainability. In summary, it is an efficient and practical implementation to set the ammonia outlet point of the ammonia distributor 9 between the air preheater of the boiler 1 and the SCR inlet flue pipe 2. This design choice helps to optimize the mixing of ammonia and flue gas, improve denitrification efficiency, reduce ammonia escape, and simplify the system layout.
[0054] In one embodiment, the regulating gate 8 of the bypass flue pipe 4 is used to adjust the amount of bypass flue gas. When the unit is under high load, the urea ammonia production function is mainly used, and the opening of the regulating gate 8 tracks the outlet temperature setting value (350-450°C) of the ammonia production reaction chamber 5; when the unit is under low load, the wide load denitrification function is mainly used, and the opening of the regulating gate 8 tracks the inlet temperature of the SCR reactor 3, and the setting value is the higher value of the lower limit of the SCR catalyst operation temperature and the outlet temperature setting value (350-450°C) of the ammonia production reaction chamber 5.
[0055] In this embodiment, when the load is high, urea is used to produce ammonia, and the opening of the regulating door 8 tracks the outlet temperature of the ammonia production reaction chamber 5 (350-450°C). When the load is low, wide load denitration is performed. The opening of the regulating door 8 tracks the higher value of the inlet temperature of the SCR reactor 3 and the outlet temperature of the ammonia production reaction chamber 5, wherein the inlet temperature setting value of the SCR reactor 3 is the lower limit of the SCR catalyst operation temperature. This embodiment ensures that the regulating door 8 of the bypass flue pipe 4 accurately adjusts the flue gas volume under different unit loads to meet the needs of the pyrolysis reaction and the denitration reaction.
[0056] In one embodiment, after the plug door 7 is fully opened, the regulating door 8 is opened, and the high-temperature flue gas of about 450 to 650°C from the turning chamber of the boiler 1 enters the bypass flue pipe 4, and is mixed with the mist urea solution sprayed by the urea spray gun in the ammonia production reaction chamber 5 to provide heat for the decomposition of urea into ammonia. There are two ways to control the bypass flue gas flow. One is to interlock the flue gas flow rate with the outlet temperature of the bypass flue pipe 4 by adjusting the opening of the regulating door 8 when only the ammonia production demand is met; the other is to interlock the flue gas flow rate with the outlet temperature of the bypass flue pipe 4 and the inlet temperature of the SCR reactor 3 by adjusting the opening of the regulating door 8 when the wide load denitrification requirements are met at the same time.
[0057] The outlet of the ammonia distributor 9 is divided into a plurality of connecting branch pipes 93, and the connecting branch pipes 93 are inserted into the position of the bypass flue pipe 4 to divide the flue cross section into a plurality of ammonia injection zones. A regulating valve 92 is provided on each branch pipe, and the regulating valve 92 is in an electric or pneumatic form. During operation, the ammonia injection zone adjustment is interlocked with the measurement result of the NOx (nitrogen oxide) zone measurement device at the outlet of the SCR reactor 3 in a one-to-one manner, and the ammonia injection amount and the outlet NOx value of each zone are adjusted through the control logic.
[0058] In the description of the present application, it should be noted that the terms "upper", "lower", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. Unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be a connection between the two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to the specific circumstances.
[0059] It should be noted that, in this application, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.
[0060] The above description is only a specific implementation of the present application, so that those skilled in the art can understand or implement the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest range consistent with the principles and novel features applied for herein.
Claims
1. A flue gas bypass ammonia production coupled with wide load denitrification device, characterized in that: It includes: A boiler (1), the boiler (1) being connected to an SCR inlet flue pipe (2), and the SCR inlet flue pipe (2) being connected to an SCR reactor (3); a bypass flue pipe (4), one end of the bypass flue pipe (4) being connected to the boiler (1), and the other end of the bypass flue pipe (4) being connected to an ammonia production reaction chamber (5), wherein a urea injection device (6) is installed in the ammonia production reaction chamber (5); An ammonia distributor (9), one end of which is in communication with the ammonia production reaction chamber (5), and the other end of which is in communication with the side wall of the SCR inlet flue pipe (2).
2. The flue gas bypass ammonia production coupled with wide load denitrification device according to claim 1, characterized in that: The urea injection device (6) comprises: A plurality of urea spray guns are installed on the bypass flue pipe (4) in an annularly spaced manner.
3. The flue gas bypass ammonia production coupled with wide load denitrification device according to claim 1, characterized in that: A plug-in door (7) is installed in the bypass flue pipe (4).
4. The flue gas bypass ammonia production coupled with wide load denitrification device according to claim 3, characterized in that: An adjusting door (8) is installed in the bypass flue pipe (4), and along the direction of the flue gas path in the bypass flue pipe (4), the adjusting door (8) is located in front of the plug-in door (7).
5. The flue gas bypass ammonia production coupled with wide load denitrification device according to claim 1, characterized in that: The ammonia distributor (9) comprises: A connecting trunk pipeline (91), one end of which is connected to the ammonia production reaction chamber (5), and the other end of which is connected to the side wall of the SCR inlet flue pipeline (2), and the connecting trunk pipeline (91) is installed with a regulating valve (92) and a flow meter (94).
6. The flue gas bypass ammonia production coupled with wide load denitrification device according to claim 1, characterized in that: The ammonia distributor (9) comprises: A connecting trunk pipeline (91), one end of which is connected to the ammonia production reaction chamber (5), and the other end of which is connected to a plurality of connecting branch pipelines (93), each of which is equipped with a regulating valve (92) and a flow meter (94), and each of which is connected to the side wall of the SCR inlet flue pipeline (2).
7. The flue gas bypass ammonia production coupled with wide load denitrification device according to claim 6, characterized in that: The connecting trunk pipeline (91) is roughly funnel-shaped, and the narrow end of the connecting trunk pipeline (91) is connected to the ammonia production reaction chamber (5), and the wide end thereof is connected to the plurality of connecting branch pipelines (93).
8. The flue gas bypass ammonia production coupled with wide load denitrification device according to claim 7, characterized in that: A plurality of guide plates are arranged in the connecting main pipeline (91), and the plurality of guide plates correspond one-to-one to the plurality of connecting branch pipelines (93) and guide the ammonia gas into the corresponding connecting branch pipelines (93).
9. The flue gas bypass ammonia production coupled with wide load denitrification device according to claim 1, characterized in that: The inlet and outlet of the SCR reactor (3) are respectively equipped with zoned nitrogen and oxygen sensors.
10. The flue gas bypass ammonia production coupled with wide load denitrification device according to claim 1, characterized in that: The flue gas introduction point of the bypass flue pipe (4) is located at the outlet of the turning chamber of the boiler (1), the inlet of the superheater of the boiler (1), or the inlet of the economizer of the boiler (1).