Atomization device and denitration system

Abstract

The utility model provides an atomization device and a denitration system.The atomization device comprises a boiler deaerator, a first pipeline, a second pipeline and a spraying mechanism, the boiler deaerator is used for outputting steam, the first pipeline communicates with the boiler deaerator and is used for leading out the steam in the boiler deaerator, and the second pipeline is used for conveying a reducing agent; the first pipeline and the second pipeline communicate with the spraying mechanism so that the steam can atomize the reducing agent. According to the atomization device, steam of the boiler deaerator is used for atomizing a reducing agent of the denitration system, heat energy recycling is achieved, and the energy-saving effect is achieved; reducing agent consumption can be reduced, and energy consumption is reduced; direct steam emission of the boiler deaerator is reduced, and noise generated by emptying of the boiler deaerator can be effectively reduced; the reducing agent and flue gas mixing temperature difference is reduced, and the denitration efficiency is improved; and meanwhile, the possibility of flue dust deposition and corrosion and rust penetration caused by reducing agent cooling and condensation is reduced.

Description

TECHNICAL FIELD

[0001] The application belongs to the field of denitration treatment, and more particularly relates to an atomizing device and a denitration system. BACKGROUND

[0002] The selective catalytic reduction technology is commonly used for the denitration of flue gas, so as to reduce the emission of nitrogen oxides. The principle is to add a reducing agent in the exhaust system, and to convert NOx into nitrogen and water under the action of a catalyst, so as to reduce the pollution to the environment. In the denitration system, the reducing agent needs to be atomized, so as to be fully contacted with the flue gas for reaction. At present, the reducing agent often uses compressed air as the atomizing gas source, which is easy to cause a large temperature difference between the reducing agent and the flue gas. CONTENT OF THE UTILITY MODEL

[0003] The purpose of the embodiment of the application is to provide an atomizing device and a denitration system, so as to solve the technical problem of a large temperature difference between the reducing agent and the flue gas in the prior art.

[0004] To achieve the above-mentioned purpose, the technical scheme adopted by the application is to provide an atomizing device for a denitration system, which comprises:

[0005] A boiler deaerator; the boiler deaerator is used for outputting steam;

[0006] A first pipeline; the first pipeline is in communication with the boiler deaerator, and is used for leading out the steam in the boiler deaerator;

[0007] A second pipeline; the second pipeline is used for conveying a reducing agent;

[0008] A spraying mechanism; the first pipeline and the second pipeline are both in communication with the spraying mechanism, so as to atomize the reducing agent by the steam.

[0009] Optionally, the boiler deaerator comprises a deaerator body and a steam discharge pipe connected to the deaerator body, a first valve for discharging steam is arranged on the steam discharge pipe, the first pipeline is connected to the steam discharge pipe, and the first pipeline is connected between the deaerator body and the first valve.

[0010] Optionally, the boiler deaerator further comprises a second valve, the second valve is arranged on the steam discharge pipe, and the second valve is located between the first pipeline and the deaerator body.

[0011] Optionally, the spraying mechanism comprises a denitration flue and a spray gun, the spray gun is arranged on the denitration flue, the spray gun has a nozzle facing the inside of the denitration flue, and the first pipeline and the second pipeline are both in communication with the spray gun.

[0012] Optionally, the first pipeline comprises a first main pipe and a plurality of first branch pipes, the first main pipe is in communication with the boiler deaerator, and the plurality of first branch pipes are all in communication with the first main pipe.

[0013] The second pipeline comprises a second main pipe for inputting the reducing agent and a plurality of second branch pipes in communication with the second main pipe;

[0014] The spray mechanism comprises a plurality of spray guns, the plurality of first branch pipes are in one-to-one correspondence with the plurality of spray guns, and the plurality of second branch pipes are in one-to-one correspondence with the plurality of first branch pipes.

[0015] Optionally, the denitration flue has opposite first and second inner sides, the first inner side is provided with at least two spray guns in the axial direction of the denitration flue, the first inner side has a first interval between adjacent two spray guns, and the second inner side is provided with at least one spray gun, and the spray gun of the second inner side faces the first interval.

[0016] Optionally, the first main pipe is provided with a third valve for adjusting the steam pressure in the first main pipe, and the first main pipe is provided with a pressure detection member for detecting the steam pressure in the first main pipe, and the third valve is in communication connection with the pressure detection member, so as to adjust the opening degree of the third valve based on the detected pressure value of the pressure detection member.

[0017] Optionally, each first branch pipe is respectively provided with a fourth valve for adjusting the steam pressure in each first branch pipe.

[0018] And / or, each second branch pipe is respectively provided with a fifth valve for adjusting the reducing agent pressure in each second branch pipe.

[0019] The application also provides a denitration system comprising the atomization device.

[0020] Optionally, the denitration system further comprises a dust remover and a denitration reactor in sequence communication, and the spray mechanism is arranged between the dust remover and the denitration reactor.

[0021] The atomization device and the denitration system provided by the application have the following beneficial effects: compared with the prior art, the atomization device in the application utilizes steam from a boiler deaerator as an atomization gas source, the steam introduced through the first pipeline and the reducing agent introduced through the second pipeline are mixed, and then the reducing agent is atomized by the spray mechanism. The atomization device atomizes the reducing agent of the denitration system by using the steam of the boiler deaerator, realizes the recycling of heat energy, and achieves the effect of energy saving; because the oxygen content in the steam of the boiler deaerator is very low, the amount of reducing agent can be reduced, and the energy consumption can be reduced; the steam of the boiler deaerator is used for atomizing the reducing agent, which reduces the direct discharge of the steam of the boiler deaerator, and can effectively reduce the noise generated by the emptying of the boiler deaerator; the temperature of the steam is higher than that of the compressed air, which reduces the temperature difference between the reducing agent and the flue gas, reduces the possibility of condensation and dewing, ensures the full contact of the atomized reducing agent with the flue gas, and is conducive to improving the denitration efficiency; at the same time, the possibility of flue ash accumulation and corrosion caused by the cooling and dewing of the reducing agent is reduced. BRIEF DESCRIPTION OF DRAWINGS

[0022] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the embodiments or prior art description will be briefly introduced. Obviously, the drawings in the following description only constitute some embodiments of the present application, and other drawings can be obtained by those skilled in the art without any creative effort on the basis of these drawings.

[0023] Figure 1 A simplified block diagram of the atomizing device in the embodiments of the present application;

[0024] Figure 2 A simplified diagram of the denitration system in the embodiments of the present application.

[0025] In the drawings, the reference signs are as follows: boiler deaerator 1; deaerator body 11; exhaust pipe 12; first valve 13; second valve 14; reducing agent storage tank 2; spraying mechanism 3; denitration flue 31; spray gun 32; first pipeline 4; third valve 42, pressure detection member 43, first branch pipe 44, fourth valve 45; second pipeline 5; second main pipe 51; delivery pump 52; second branch pipe 53; fifth valve 54; dust collector 6; denitration reactor 7. DETAILED DESCRIPTION

[0026] In order to make the technical problems to be solved by the present application, the technical solutions and beneficial effects more clearly understood, the present application will be further described in detail below in combination with the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and not to limit the present application.

[0027] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it can be directly on the other element or indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element.

[0028] It should be understood that the terms "length", "width", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only used to facilitate the description of the present application and simplify the description, and therefore cannot be understood as indicating or implying that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application.

[0029] In addition, the terms "first", "second", "third", etc. are used only for descriptive purposes and are not to be construed as indicating or implying relative importance or an ordered ranking of the indicated technical features. Thus, features defined with "first", "second" or "third" can explicitly or implicitly include one or more of such features. In the description of the present application, the meaning of "a plurality of" is two or more, unless otherwise expressly and specifically defined.

[0030] Selective catalytic reduction denitration technology, referred to as SCR technology, is a technology for reducing nitrogen oxide (NOx) emissions, widely used in glass, automobile, industrial boiler, power plant and other fields. SCR technology injects a reducing agent into the flue gas, which is reduced to harmless nitrogen and water under the action of a catalyst. This process occurs on the surface of the catalyst, which can be a metal oxide such as vanadium, titanium, tungsten, etc. The reducing agent can be ammonia water, liquid ammonia, urea, etc.

[0031] In the SCR denitration system, atomization is a key step, mainly involving spraying the reducing agent in the form of mist into the flue gas to ensure that it is fully mixed with nitrogen oxides and reacts. The quality of atomization directly affects the denitration efficiency of the SCR system. The current SCR denitration system mostly uses compressed air as the atomizing gas source, and the reducing agent is pumped from the tank through the pipeline to the flue gas spraying mechanism 3 in front of the denitration reactor 7, then the normal temperature compressed air atomizes the normal temperature reducing agent in the flue gas spray gun 32, the flue gas and the atomized reducing agent are mixed in the grid, and the reducing agent is accelerated by the catalyst to reduce the nitrogen oxides in the flue gas to harmless nitrogen and water. After the reducing agent is atomized by the normal temperature compressed air and mixed with the high temperature flue gas, due to the large temperature difference, there is local cooling and condensation during the mixing of the atomized reducing agent and the flue gas, which leads to insufficient mixing of the ammonia gas and the flue gas, resulting in low denitration efficiency, and the reducing agent cooling and condensation also easily leads to easy ash accumulation and corrosion in this section of the flue gas.

[0032] An online flue gas analysis system can also be provided after the denitration reactor 7 for analyzing the composition of the flue gas after denitration. Since the compressed air contains 21% oxygen, the oxygen content of most industrial flue gas is much less than 21%, for example, the oxygen content of the flat glass industry flue gas is 8%, when the oxygen content is greater than 8%, the flue gas analysis data needs to be multiplied by a base greater than 8%, which causes the nitrogen oxide conversion data to be high, and the reducing agent usage to be relatively increased.

[0033] Based on the above factors, the present application provides an atomizing device, please refer to Figure 1 , now the atomizing device provided by the embodiment of the present application will be described. The atomizing device of the present embodiment is used in a denitration system, and the atomizing device comprises:

[0034] A boiler deaerator 1; the boiler deaerator 1 is used to output steam;

[0035] The first pipeline 4 is connected with the boiler deaerator 1, and is used for leading out the steam in the boiler deaerator 1.

[0036] The second pipeline 5 is used for conveying the reducing agent.

[0037] The spraying mechanism 3 is connected with the first pipeline 4 and the second pipeline 5, so that the steam atomizes the reducing agent.

[0038] The atomization device of the embodiment uses the steam from the boiler deaerator 1. The boiler deaerator 1 is a device for removing the dissolved oxygen in the boiler feed water, and its main purpose is to prevent the damage of the boiler and its piping system due to oxidation corrosion. The boiler deaerator 1 will discharge a large amount of steam while removing the oxygen in the boiler feed water, especially the common thermal type boiler deaerator 1. These steams can be used for atomization of the reducing agent.

[0039] The steam from the boiler deaerator 1 is used as the atomization gas source in the embodiment. The first pipeline 4 is used as a transmission channel of the steam from the boiler deaerator 1, and is connected with the boiler deaerator 1, so as to ensure that the steam can be smoothly led out from the boiler deaerator 1 and used for atomizing the reducing agent. The second pipeline 5 is used for conveying the reducing agent. The reducing agent is a key substance in the denitration process, and is used for reacting with the nitrogen oxides in the flue gas, so as to reduce the emission thereof. The reducing agent can be at least one of ammonia water, liquid ammonia and urea. Through the second pipeline 5, the reducing agent is stably and continuously conveyed to the spraying mechanism 3, and is ready to be mixed with the steam for atomization.

[0040] The spraying mechanism 3 is used for spraying the atomized reducing agent, and is connected with the first pipeline 4 and the second pipeline 5. Specifically, the first pipeline 4 and the second pipeline 5 can be connected first and then connected with the spraying mechanism 3, so that the steam and the reducing agent are fully mixed, and then sprayed from the spraying mechanism 3 to form the atomized reducing agent; or the first pipeline 4 and the second pipeline 5 can be converged on the spraying mechanism 3, so that the steam and the reducing agent meet and mix in the spraying mechanism 3, and then are sprayed from the spraying mechanism 3 together, so as to realize the atomization of the reducing agent. The atomized reducing agent has a larger surface area, and can more fully contact and react with the nitrogen oxides in the flue gas, so as to improve the denitration efficiency.

[0041] The atomization device of the embodiment has the following advantages:

[0042] 1. The denitration system is mainly used for reducing the content of nitrogen oxides in the flue gas, so as to meet the environmental protection requirements. The steam from the boiler deaerator 1 is usually directly discharged and treated. The steam from the boiler deaerator 1 is used for atomizing the reducing agent of the denitration system, so as to realize the recycling of heat energy, achieve the energy-saving effect, and further promote the environmental protection benefits of the whole system.

[0043] Second, the atomization of the reducing agent in the denitrification system requires a continuous and stable atomizing gas source, but in industrial production, it is difficult to achieve a continuous and stable supply of recoverable gas. The boiler deaerator 1, however, can provide a continuous and stable steam supply, thus providing a foundation for the continuous and stable operation of the denitrification system and meeting the requirements of flue gas treatment. Moreover, just as boilers are widely used in industry, so too is the boiler deaerator 1, allowing the atomization device in this embodiment to have more application scenarios and opportunities.

[0044] 3. The boiler deaerator 1 itself is a deaeration device with good internal sealing conditions and very low oxygen content. The oxygen content in the discharged steam mainly comes from the escape of dissolved oxygen in the boiler feedwater. External oxygen should not be mixed in. Therefore, the oxygen content in the steam is very low, which is less than the oxygen content in the flue gas and much less than the oxygen content in compressed air. This is beneficial for calculating flue gas analysis based on the oxygen content of the flue gas after denitrification, which can reduce the amount of reducing agent and reduce energy consumption.

[0045] Fourth, boiler deaerator 1 typically generates noise during steam venting, causing environmental noise pollution. In this embodiment, the steam from boiler deaerator 1 is drawn out and used for atomizing a reducing agent, reducing the direct emission of steam from boiler deaerator 1 and effectively lowering or even eliminating the noise generated during venting.

[0046] Fifth, the steam temperature of boiler deaerator 1 is much higher than that of compressed air at normal temperature, usually reaching over 120℃. Using it to atomize ammonia water reduces the temperature difference between the reducing agent and the flue gas, reduces the possibility of condensation, and ensures sufficient contact between the atomized reducing agent and the flue gas, which is beneficial to improving denitrification efficiency. At the same time, it reduces the possibility of ash accumulation and corrosion in the flue due to the cooling and condensation of the reducing agent.

[0047] Please see Figure 2 In some embodiments of this application, the boiler deaerator 1 includes a deaerator body 11 and an exhaust pipe 12 connected to the deaerator body 11. A first valve 13 for discharging steam is provided on the exhaust pipe. A first pipeline 4 is connected to the exhaust pipe 12 and is connected between the deaerator body 11 and the first valve 13.

[0048] The deaerator body 11 is the main part of the boiler deaerator 1, and the exhaust pipe 12 is connected to the deaerator body 11 and used for discharging excess steam generated inside the deaerator. The deaerator body 11 mainly includes a deaerator water tank and a deaerator tower, and the deaerator tower is installed above the deaerator water tank. The exhaust pipe 12 is usually installed at the top of the deaerator tower to facilitate the discharge of steam. The first valve 13 is arranged on the exhaust pipe 12 and used for controlling the discharge amount of steam. The first valve 13 can usually be an automatic control valve such as an electrically driven exhaust valve, which can realize automatic control of the boiler exhaust by cooperating with a pressure sensor and other boiler deaerator 1 working condition monitoring devices.

[0049] In the atomizing device of the embodiment, the first pipeline 4 is connected to the exhaust pipe 12 to facilitate the extraction of steam in the boiler deaerator 1. The first pipeline 4 is connected between the deaerator body 11 and the first valve 13. On the one hand, the exhaust noise of the boiler deaerator 1 is caused by the exhaust of the first valve 13. The steam is extracted before passing through the first valve 13, which can reduce the frequency and time of opening of the first valve 13, thereby further reducing the exhaust noise of the first valve 13. On the other hand, the first valve 13 can still independently play its exhaust function, thereby ensuring the normal working condition of the boiler deaerator 1.

[0050] Please refer to Figure 2 In some embodiments of the present application, the boiler deaerator 1 further includes a second valve 14, which is arranged on the exhaust pipe 12 and located between the first pipeline 4 and the deaerator body 11.

[0051] Compared with the previous embodiment, the second valve 14 is newly arranged on the exhaust pipe 12 and located between the first pipeline 4 and the deaerator body 11, i.e., the second valve 14 is arranged before the first pipeline 4. The first pipeline 4 is connected between the deaerator body 11 and the first valve 13, so the first pipeline 4 is connected between the first valve 13 and the second valve 14. The second valve 14 is arranged before the first pipeline 4 and the first valve 13. The first pipeline 4 is used to extract steam from the boiler deaerator tower for atomization of the reducing agent, and the first valve 13 is used to control the exhaust of steam from the boiler deaerator tower. Therefore, the second valve 14 can simultaneously control the on-off of steam atomization and steam exhaust. The second valve 14 mainly plays a blocking function and can usually be a stop valve. The first pipeline 4 is connected between the first valve 13 and the second valve 14, which can reduce the frequency and time of opening of the first valve 13 without affecting the independent exhaust of the first valve 13, and can also realize the cutting-off of steam in the first pipeline 4 by using the second valve 14.

[0052] Please refer to Figure 2In some embodiments of the present application, the spray mechanism 3 comprises a denitration flue 31 and a spray gun 32, the spray gun 32 is arranged on the denitration flue 31, the spray gun 32 has a nozzle facing the inside of the denitration flue 31, and the first pipeline 4 and the second pipeline 5 are both in communication with the spray gun 32.

[0053] The spray mechanism 3 is a key equipment in the denitration system, and its main function is to spray the mixed reducing agent and steam into atomization, and then spray the atomized reducing agent into the denitration flue 31 to react with nitrogen oxides in the flue gas, thereby reducing the emission of nitrogen oxides. In the present embodiment, the spray mechanism 3 comprises a denitration flue 31 and a spray gun 32, wherein the denitration flue 31 is a passage for the boiler flue gas emission, and at the same time provides a space for the atomization of the reducing agent. The spray gun 32 is the core component of the spray mechanism 3, which is arranged on the denitration flue 31 and has a nozzle facing the inside of the denitration flue 31. The function of the spray gun 32 is to atomize the steam and reducing agent mixture input from the first pipeline 4 and the second pipeline 5, and spray it into the denitration flue 31, so that the atomized reducing agent is fully contacted with the flue gas, and the subsequent catalytic reduction reaction provides good conditions.

[0054] Please refer to Figure 2 In some embodiments of the present application, the first pipeline 4 comprises a first main pipe and a plurality of first branch pipes 44, the first main pipe is in communication with the boiler deaerator 1, and the plurality of first branch pipes 44 are all in communication with the first main pipe; the second pipeline 5 comprises a second main pipe 51 and a plurality of second branch pipes 53, the second main pipe 51 is used for inputting the reducing agent, and the plurality of second branch pipes 53 are all in communication with the second main pipe 51; the spray mechanism 3 comprises a plurality of spray guns 32, the plurality of first branch pipes 44 are in one-to-one correspondence with the plurality of spray guns 32, and the plurality of second branch pipes 53 are in one-to-one correspondence with the plurality of first branch pipes 44.

[0055] The single spray gun 32 can atomize the reducing agent more preferentially, but in most cases it is difficult to meet the demand of flue gas denitration. In the embodiment, the first pipeline 4 includes a first main pipe and a plurality of first branch pipes 44. The first main pipe is a main steam conveying pipe connecting between the boiler deaerator 1 and the spray mechanism 3. It receives steam from the boiler deaerator 1 and conveys it to the plurality of first branch pipes 44. The first branch pipes 44 are pipes branched from the first main pipe, and the number of the first branch pipes 44 is plural, which is usually consistent with the number of the spray guns 32, so that the first branch pipes 44 are in one-to-one correspondence with the plurality of spray guns 32, that is, each first branch pipe 44 is respectively connected to one spray gun 32. Each first branch pipe 44 is responsible for conveying a certain amount of steam to the spray gun 32 connected thereto for atomizing the reducing agent. The second main pipe 51 is the main input pipe of the reducing agent. It receives the reducing agent from the reducing agent storage or preparation system and conveys it to the plurality of second branch pipes 53. A conveying power device such as a conveying pump 52 can be provided on the second main pipe 51 to provide stable power for the conveying of the reducing agent. The second branch pipes 53 are pipes branched from the second main pipe 51, and the number of the second branch pipes 53 is plural, which is usually consistent with the number of the first branch pipes 44. The second branch pipes 53 are in one-to-one correspondence with the plurality of first branch pipes 44, that is, each second branch pipe 53 is respectively connected to one first branch pipe 44. Each second branch pipe 53 is responsible for conveying a certain amount of reducing agent to the first branch pipe 44 connected thereto, so that the reducing agent and steam meet and mix fully in the first branch pipe 44. Each first branch pipe 44 is respectively connected to one spray gun 32, so that the mixed reducing agent and steam are sprayed into the flue gas denitration duct 31 and fully mixed with the flue gas.

[0056] The first pipeline 4 branches into a plurality of first branch pipes 44 for conveying steam to the corresponding spray guns 32, so that each spray gun 32 can obtain a relatively independent steam supply. Similarly, the second pipeline 5 branches into a plurality of second branch pipes 53 for conveying reducing agent to the corresponding spray guns 32, so that each spray gun 32 can obtain a relatively independent reducing agent supply, thereby reducing the mutual influence between the spray guns 32. The plurality of spray guns 32 jointly spray atomized reducing agent into the flue gas denitration duct 31, which can ensure that sufficient and fully atomized reducing agent is sprayed into the flue gas denitration duct 31.

[0057] Please refer to Figure 2 In some embodiments of the present application, the flue gas denitration duct 31 has a first inner side and a second inner side. The first inner side is provided with at least two spray guns 32 along the axial direction of the flue gas denitration duct 31, and the adjacent two spray guns 32 on the first inner side have a first interval. The second inner side is provided with at least one spray gun 32, and the spray gun 32 on the second inner side faces the first interval.

[0058] When the spray mechanism 3 has multiple spray guns 32, the multiple spray guns 32 need to be well coordinated to achieve good coverage. In the embodiment, the denitration flue 31 has opposite first and second inner sides, and the spray guns 32 can be arranged on the first and second inner sides respectively to spray into the denitration flue 31 from both sides. Specifically, on the first inner side, at least two spray guns 32 are arranged along the axial direction of the denitration flue 31 (i.e. the main extension direction of the flue), and the adjacent two spray guns 32 are kept at a certain distance, which is referred to as the first interval. The first interval can ensure that each spray gun 32 can effectively cover its spraying area, while avoiding waste caused by overlapping spraying. On the second inner side, at least one spray gun 32 is also arranged. The spraying direction of the spray gun 32 on the second inner side is specially aligned with the first interval between the adjacent two spray guns 32 on the first inner side. Such design can make up for the area on the first inner side that cannot be covered by spraying between the adjacent two spray guns 32, so as to maximize the coverage of the internal space of the denitration flue 31 on the basis of as much overlapping spraying range as possible. In addition, not only can the spray gun 32 on the second inner side be directed towards the interval between the adjacent spray guns 32 on the first inner side, but when multiple spray guns 32 are arranged on the second inner side, the spray guns 32 on the first inner side can also be directed towards the interval between the adjacent spray guns 32 on the second inner side, i.e. the multiple spray guns 32 on both sides are staggered up and down, so as to improve the effective coverage range of the spray guns 32 on the basis of reducing the overlapping spraying range.

[0059] In addition, there are various specific arrangements of the multiple spray guns 32, for example, the multiple spray guns 32 can be uniformly arranged circumferentially along the denitration flue 31, or the multiple spray guns 32 can be arranged at intervals along the axial direction of the denitration flue 31.

[0060] Please refer to Figure 2 In some embodiments of the present application, a third valve 42 for adjusting the steam pressure in the first main pipe is arranged on the first main pipe, and a pressure detection member 43 for detecting the steam pressure in the first main pipe is arranged on the first main pipe, and the third valve 42 is in communication connection with the pressure detection member 43, so as to adjust the opening degree of the third valve 42 based on the pressure value detected by the pressure detection member 43.

[0061] The third valve 42 is arranged on the first main pipe, and mainly functions to regulate the steam pressure in the first main pipe, so as to ensure that the steam has sufficient pressure to atomize the reducing agent, and meanwhile, the pressure is not too high to cause backflow of the reducing agent. To this end, a pressure detecting element 43 is also arranged on the first main pipe, and functions to detect the steam pressure in the first main pipe in real time. The third valve 42 can be an electric or pneumatic regulating valve, and the pressure detecting element 43 can be a pressure gauge, a pressure sensor or the like. The pressure detecting element 43 is in communication connection with the third valve 42, so that the opening of the third valve 42 is regulated according to the pressure value detected by the pressure detecting element 43. When the pressure detecting element 43 detects that the steam pressure in the first main pipe changes, it will immediately transmit the detected pressure value to the third valve 42. After receiving the information, the third valve 42 will automatically regulate its opening according to preset logic. If the steam pressure is too high, the third valve 42 can slightly reduce the opening, so as to reduce the steam pressure flowing into the first main pipe; if the steam pressure is too low, the third valve 42 can increase the opening, so as to increase the steam pressure flowing into the first main pipe. In this way, the first main pipe can maintain an appropriate pressure value, and the steam pressure in the first branch pipe 44 can be kept within an appropriate range.

[0062] Please refer to Figure 2 In some embodiments of the present application, each first branch pipe 44 is provided with a fourth valve 45 for regulating the steam pressure in each first branch pipe 44.

[0063] The third valve 42 can regulate the steam pressure in the first branch pipe 44 by regulating the steam pressure in the first main pipe, but it cannot independently regulate the steam pressure in each first branch pipe 44. In the present embodiment, each first branch pipe 44 is provided with a fourth valve 45, so that the steam pressure in each first branch pipe 44 can be independently regulated, so as to ensure that the steam pressure in each branch pipe reaches an appropriate value, and the steam in each first branch pipe 44 can have a good atomization effect on the reducing agent. The fourth valve 45 can be an electric or pneumatic regulating valve, or a manual valve such as a ball valve.

[0064] Please refer to Figure 2 In some embodiments of the present application, each second branch pipe 53 is provided with a fifth valve 54 for regulating the reducing agent pressure in each second branch pipe 53. Similar to the previous embodiment, in the present embodiment, each second branch pipe 53 is provided with a fifth valve 54, so that the reducing agent pressure in each second branch pipe 53 can be independently regulated, so as to ensure that the reducing agent pressure in each second branch pipe 53 reaches an appropriate value. The fifth valve 54 can be an electric or pneumatic regulating valve, or a manual valve such as a ball valve.

[0065] The fourth valve 45 can adjust the steam pressure in the first branch pipe 44, and the fifth valve 54 can adjust the reducing agent pressure in the second branch pipe 53. The two can cooperate with each other to make the steam pressure and the reducing agent pressure reach the preset value, thereby ensuring good atomization. For example, in some embodiments, the steam pressure can be adjusted to 0.25 MPa, and the reducing agent pressure is comparable to the steam pressure and slightly less than the steam pressure. The two can be mixed to achieve good atomization effect. In addition to adjusting the pressure, the fourth valve 45 and the fifth valve 54 can actually adjust the flow, so that the flow of steam and the flow of reducing agent are matched. For example, in some embodiments, the flow of steam can be adjusted to 400 m 3 / h, and the flow of ammonia as the reducing agent can be adjusted to 500 L / h.

[0066] For example, Figure 2 , in the atomization device in Figure 2 , the first main pipe is connected between the first valve 13 and the second valve 14 of the exhaust pipe 12 of the deaerator 1 of the boiler, to lead out the steam in the deaerator body 11. The first main pipe is provided with a third valve 42 and a pressure detection piece 43 to control the steam pressure in the first main pipe. The first main pipe is connected with four first branch pipes 44, and each of the four first branch pipes 44 is provided with a fourth valve 45 for controlling the steam pressure in each first branch pipe 44. The second main pipe 51 is connected with a delivery pump 52 to deliver the reducing agent. The second main pipe 51 is divided into four second branch pipes 53, and each of the four second branch pipes 53 is provided with a fifth valve 54 for controlling the pressure of the reducing agent in each second branch pipe 53. The four second branch pipes 53 are connected with the four first branch pipes 44 one by one, to realize the mixing of steam and reducing agent. The denitration flue 31 is provided with four spray guns 32, which are arranged on two sides, and each side is provided with two spray guns 32. The spray guns 32 on the two sides are arranged in an up-down staggered manner. The four first branch pipes 44 are connected with the four spray guns 32 one by one, to supply the mixture of steam and reducing agent to the four spray guns 32 respectively. The mixture of steam and reducing agent is sprayed into the denitration flue 31 from the four spray guns 32 respectively, and is mixed with the flue gas in the denitration flue 31, so as to facilitate the reaction of the reducing agent with the nitrogen oxides in the flue gas under the action of the catalyst.

[0067] Based on the above atomizing device, the application further provides a denitration system, which comprises the atomizing device in each of the above embodiments. The denitration system is used for reducing nitrogen oxides in flue gas. The principle is to inject a reducing agent into the flue gas, and to reduce the nitrogen oxides into harmless nitrogen and water under the action of a catalyst. The catalyst can be a metal oxide, such as vanadium, titanium, tungsten, etc. The reducing agent can be ammonia water, liquid ammonia, urea, etc. In order to make the reducing agent fully contact with the flue gas, the denitration system can be provided with an atomizing device to atomize the reducing agent. The present embodiment utilizes steam from a boiler deaerator 1 as an atomizing gas source, mixes the steam introduced through a first pipeline 4 with the reducing agent introduced through a second pipeline 5, and then sprays out through a spraying mechanism 3 to achieve good atomization of the reducing agent, so that it fully contacts and reacts with the flue gas. The denitration system of the present embodiment utilizes the steam from the boiler deaerator 1 to atomize the reducing agent of the denitration system, realizes the recycling of heat energy, and achieves the effect of energy saving; because the oxygen content in the steam from the boiler deaerator 1 is very low, the amount of reducing agent can be reduced, and the energy consumption can be reduced; the steam from the boiler deaerator 1 is used for atomizing the reducing agent, which reduces the direct discharge of steam from the boiler deaerator 1, and can effectively reduce the noise generated by the emptying of the boiler deaerator 1; the temperature of the steam is higher than that of compressed air, which reduces the temperature difference between the reducing agent and the flue gas, reduces the possibility of condensation and dewing, ensures the full contact of the atomized reducing agent with the flue gas, and is beneficial to improving the denitration efficiency; at the same time, the possibility of flue ash accumulation and corrosion caused by the cooling and dewing of the reducing agent is reduced.

[0068] Please refer to Figure 2 In some embodiments of the present application, the denitration system further comprises a dust collector 6 and a denitration reactor 7 which are sequentially communicated, and the spraying mechanism 3 is arranged between the dust collector 6 and the denitration reactor 7.

[0069] The dust collector 6 is located at the front end of the denitration system and is an inlet treatment device of the flue gas. The dust collector 6 is used for removing particulate matters in the flue gas to ensure that the flue gas entering the subsequent device is relatively clean. The denitration reactor 7 is usually provided with a catalyst, so that the reducing agent reacts with the nitrogen oxides in the flue gas under the action of the catalyst to generate nitrogen and water. The spraying mechanism 3 is the spraying part of the atomizing device, which can spray out the reducing agent fully mixed with the steam, so that the reducing agent is fully atomized.

[0070] When the denitration system is running, flue gas enters the dust collector 6 from the flue gas inlet, and the dust collector 6 removes most of the particulate matters in the flue gas, making the flue gas cleaner. Then, the dust-removed flue gas enters the spraying mechanism 3. The spraying mechanism 3 sprays the atomized reducing agent, and the atomized reducing agent is fully mixed with the flue gas. The flue gas mixed with the reducing agent enters the denitration reactor 7. In the denitration reactor 7, the reducing agent and the nitrogen oxides in the flue gas undergo oxidation-reduction reactions under the action of the catalyst, generating nitrogen and water, so that the nitrogen oxides in the flue gas are removed or reduced to a level meeting the environmental protection requirements, achieving the denitration treatment of the flue gas, and the denitrated flue gas is discharged from the flue gas outlet. An online flue gas analysis system is usually arranged at the flue gas outlet, for analyzing the content of the nitrogen oxides in the flue gas, to ensure that it meets the emission requirements.

[0071] The above only describes the preferred embodiments of the present application and is not used to limit the present application. Any modification, equivalent replacement and improvement made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. An atomizing device for a denitration system, characterized by, The atomization device comprises: a boiler deaerator, wherein the boiler deaerator is configured to output steam; a first pipeline, wherein the first pipeline is connected to the boiler deaerator and configured to lead out the steam in the boiler deaerator; a second pipeline, wherein the second pipeline is configured to transport a reducing agent; a spraying mechanism, wherein the first pipeline and the second pipeline are both connected to the spraying mechanism, so that the steam atomizes the reducing agent.

2. The atomization device of claim 1, wherein, The boiler deaerator comprises a deaerator body and a steam discharge pipe connected to the deaerator body, wherein a first valve for discharging steam is arranged on the steam discharge pipe, the first pipeline is connected to the steam discharge pipe, and the first pipeline is connected between the deaerator body and the first valve.

3. The atomization device of claim 2, wherein, The boiler deaerator further comprises a second valve, wherein the second valve is arranged on the steam discharge pipe and located between the first pipeline and the deaerator body.

4. The atomization device of claim 1, wherein, The spraying mechanism comprises a denitration flue and a spray gun, wherein the spray gun is arranged on the denitration flue, the spray gun has a nozzle facing the inside of the denitration flue, and the first pipeline and the second pipeline are both connected to the spray gun.

5. The atomizing device of claim 4, wherein The first pipeline comprises a first main pipe and a plurality of first branch pipes, wherein the first main pipe is connected to the boiler deaerator, and the plurality of first branch pipes are all connected to the first main pipe. The second pipeline comprises a second main pipe and a plurality of second branch pipes, wherein the second main pipe is configured to input the reducing agent, and the plurality of second branch pipes are all connected to the second main pipe. The spraying mechanism comprises a plurality of spray guns, wherein the plurality of first branch pipes are connected to the plurality of spray guns one by one, and the plurality of second branch pipes are connected to the plurality of first branch pipes one by one.

6. The atomizing device of claim 5, wherein The denitration flue has opposite first and second inner sides, wherein the first inner side is provided with at least two spray guns along the axial direction of the denitration flue, the first inner side has a first interval between adjacent two spray guns, and the second inner side is provided with at least one spray gun, and the spray gun on the second inner side faces the first interval.

7. The atomizing device as described in claim 5 or 6, characterized in that, The first main pipe is provided with a third valve for adjusting the steam pressure in the first main pipe, and the first main pipe is provided with a pressure detection member for detecting the steam pressure in the first main pipe, wherein the third valve is communicatively connected to the pressure detection member, so as to adjust the opening degree of the third valve based on the pressure value detected by the pressure detection member.

8. The atomizing device of claim 5 or 6, wherein Each first branch pipe is provided with a fourth valve for adjusting the steam pressure in the first branch pipe. Each second branch pipe is provided with a fifth valve for adjusting the reducing agent pressure in the second branch pipe.

9. A denitration system characterized by, The denitration system comprises the atomization device according to any one of claims 1-8.

10. The denitration system according to claim 9, wherein The denitration system further comprises a dust collector and a denitration reactor connected in sequence, and the spraying mechanism is arranged between the dust collector and the denitration reactor.

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