Atomization device and denitration system

Abstract

The invention 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 present application belongs to the field of denitration treatment, and more specifically, to an atomization device and a denitration system. Background Art

[0002] Selective catalytic reduction technology is often used for flue gas denitration to reduce nitrogen oxide emissions. The principle is to add a reducing agent to the exhaust system to convert NOx into nitrogen and water under the action of a catalyst, thereby reducing environmental pollution. In the denitration system, the reducing agent needs to be atomized so that it can fully contact and react with the flue gas. At present, compressed air is often used as the atomization gas source for the reducing agent, which easily causes a large temperature difference between the reducing agent and the flue gas. Summary of the invention

[0003] The purpose of the embodiments of the present application is to provide an atomization device and a denitrification system to solve the technical problem of large temperature difference between reducing agent and flue gas in the prior art.

[0004] In order to achieve the above-mentioned purpose, the technical solution adopted in the present application is: to provide an atomizing device for a denitration system, the atomizing device comprising:

[0005] Boiler deaerator; Boiler deaerator is used to output steam;

[0006] The first pipeline is connected to the boiler deaerator and is used to lead out the steam in the boiler deaerator;

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

[0008] The first pipeline and the second pipeline are both connected to the spray mechanism so that the steam atomizes the reducing agent.

[0009] Optionally, the boiler deaerator includes a deaerator body and an exhaust pipe connected to the deaerator body, the exhaust pipe is provided with a first valve for discharging steam, the first pipeline is connected to the exhaust pipe, and the first pipeline is connected between the deaerator body and the first valve.

[0010] Optionally, the boiler deaerator further includes a second valve, which is arranged on the exhaust pipe and located between the first pipeline and the deaerator body.

[0011] Optionally, the spray mechanism includes a denitrification flue and a spray gun, the spray gun is arranged on the denitrification flue, the nozzle of the spray gun faces the inside of the denitrification flue, and the first pipeline and the second pipeline are both connected to the spray gun.

[0012] Optionally, the first pipeline includes a first main pipe and a plurality of first branch pipes, 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;

[0013] The second pipeline includes a second main pipe and a plurality of second branch pipes, the second main pipe is used to input the reducing agent, and the plurality of second branch pipes are all connected to the second main pipe;

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

[0015] Optionally, the denitrification flue has a first inner side and a second inner side relative to each other, the first inner side is provided with at least two spray guns along the axial direction of the denitrification flue, a first interval is provided between two adjacent spray guns on the first inner side, 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.

[0016] Optionally, a third valve for adjusting the steam pressure in the first main pipe is provided on the first main pipe, and a pressure detection component for detecting the steam pressure in the first main pipe is provided on the first main pipe. The third valve is communicatively connected with the pressure detection component to adjust the opening of the third valve based on the pressure value detected by the pressure detection component.

[0017] Optionally, each first branch pipe is 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 pressure of the reducing agent in each second branch pipe.

[0019] The present application also provides a denitrification system, which includes the above-mentioned atomization device.

[0020] Optionally, the denitration system further includes a dust collector and a denitration reactor which are connected in sequence, and the spray mechanism is arranged between the dust collector and the denitration reactor.

[0021] The beneficial effects of the atomizing device and denitration system provided by the present application are as follows: compared with the prior art, the atomizing device in the embodiment of the present application uses steam from the boiler deaerator as the atomizing gas source, introduces steam through the first pipeline and mixes the reducing agent introduced through the second pipeline, and then sprays out through the spray mechanism to realize the atomization of the reducing agent. The atomizing device uses the steam of the boiler deaerator to atomize the reducing agent of the denitration system, realizes the recovery and utilization of heat energy, and achieves energy saving effect; because the oxygen content in the steam of the boiler deaerator is very low, the amount of reducing agent can be reduced, and energy consumption can be reduced; the steam of the boiler deaerator is used for the atomization of the reducing agent, which reduces the direct discharge of steam from the boiler deaerator, and can effectively reduce the noise generated by the emptying of the boiler deaerator; the temperature of steam is higher than that of compressed air, which reduces the mixing temperature difference between the reducing agent and the flue gas, reduces the possibility of condensation, ensures the full contact between the atomized reducing agent and the flue gas, and is conducive to improving the denitration efficiency; at the same time, it reduces the possibility of flue dust accumulation and corrosion and rust penetration caused by cooling and condensation of the reducing agent. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the embodiments or the description of the prior art 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 paying creative labor.

[0023] Figure 1 It is a simplified block diagram of the atomization device in the embodiment of the present application;

[0024] Figure 2 This is a simplified diagram of the denitrification system in an embodiment of the present application.

[0025] Among them, the figure marks in the figure are: boiler deaerator 1; deaerator body 11; exhaust pipe 12; first valve 13; second valve 14; reducing agent storage tank 2; spray mechanism 3; denitrification flue 31; spray gun 32; first pipeline 4; third valve 42, pressure detection component 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; denitrification reactor 7. DETAILED DESCRIPTION

[0026] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used 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", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0029] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0030] Selective catalytic reduction denitrification technology, referred to as SCR technology, is a technology used to reduce nitrogen oxide (NOx) emissions and is widely used in glass, automobiles, industrial boilers, power plants and other fields. SCR technology injects a reducing agent into the flue gas, and under the action of a catalyst, nitrogen oxides are reduced to harmless nitrogen and water. 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, which mainly involves spraying the reducing agent into the flue gas in the form of mist 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. At present, most SCR denitration systems use compressed air as the atomization gas source. The reducing agent comes out of the tank through a pump and a pipeline, and is introduced to the flue spray mechanism 3 in front of the denitration reactor 7. Then, the normal temperature compressed air atomizes the normal temperature reducing agent in the flue spray gun 32, and the flue gas and the atomized reducing agent are mixed through the grid. The catalyst accelerates the reduction reaction of the reducing agent and the flue gas nitrogen oxides, and reduces NOx to harmless nitrogen and water. After the normal temperature compressed air atomizes the reducing agent and mixes it with the high-temperature flue gas, due to the large temperature difference, there is local cooling and condensation in the process of mixing the atomized reducing agent and the flue gas, resulting in insufficient mixing of gas ammonia and flue gas, resulting in low denitration efficiency, and the cooling and condensation of the reducing agent also easily causes this section of the flue to accumulate dust and corrode and rust.

[0032] An online flue gas analysis system can also be set after the denitration reactor 7 to analyze the flue gas composition after denitration. Since the compressed air contains 21% oxygen, the basic oxygen content of most industrial flue gases is much less than 21%. For example, the basic oxygen content of flue gas in the flat glass industry is 8%. When the oxygen content is greater than 8%, the flue gas analysis data must be multiplied by a base greater than 8%, which results in a higher conversion data for nitrogen oxides and a relatively increased amount of reducing agent.

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

[0034] Boiler deaerator 1; Boiler deaerator 1 is used to output steam;

[0035] The first pipeline 4 is connected to the boiler deaerator 1 and is used to lead out the steam in the boiler deaerator 1;

[0036] The second pipeline 5 is used to transport the reducing agent;

[0037] The spray mechanism 3; the first pipeline 4 and the second pipeline 5 are both connected to the spray mechanism 3 so that the steam atomizes the reducing agent.

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

[0039] This embodiment uses the steam from the boiler deaerator 1 as the atomizing gas source. The first pipeline 4 serves as a transmission channel for the steam from the boiler deaerator 1. It is connected to the boiler deaerator 1 to ensure that the steam can be smoothly drawn out from the boiler deaerator 1 for atomizing the reducing agent. The second pipeline 5 is specifically used to transport the reducing agent. The reducing agent is a key substance in the denitrification process and is used to react with nitrogen oxides in the flue gas to reduce its emissions. 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 transported to the spray mechanism 3, ready to be mixed with steam for atomization.

[0040] The spray mechanism 3 is used to spray out the atomized reducing agent, so it is connected to both 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 to the spray mechanism 3, so that the steam and the reducing agent are fully mixed, and then sprayed from the spray mechanism 3 to form the atomized reducing agent; the first pipeline 4 and the second pipeline 5 can also be combined on the spray mechanism 3, so that the steam and the reducing agent meet and mix inside the spray mechanism 3, and then sprayed from the spray mechanism 3 together to achieve the atomization of the reducing agent. The atomized reducing agent has a larger surface area, which can more fully contact and react with the nitrogen oxides in the flue gas, thereby improving the denitrification efficiency.

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

[0042] 1. The denitrification system is mainly used to reduce the nitrogen oxide content in the flue gas to meet environmental protection requirements. The steam of the boiler deaerator 1 is usually directly discharged. The steam of the boiler deaerator 1 is used to atomize the reducing agent of the denitrification system, realizing the recovery and utilization of heat energy, achieving energy-saving effects, and further promoting the environmental benefits of the entire system.

[0043] 2. The atomization of the reducing agent in the denitration system requires a continuous and stable atomization gas source, but the recyclable gas source in industrial production is difficult to achieve a continuous and stable supply. The boiler deaerator 1 can provide a continuous and stable steam supply, thus providing a basis for the continuous and stable operation of the denitration system and meeting the needs of flue gas treatment. Moreover, just as boilers are widely used in industry, so are the supporting boiler deaerators 1, so that the atomization device of this embodiment can have more usage scenarios and opportunities.

[0044] 3. The boiler deaerator 1 itself is a deoxygenation device with good internal sealing conditions and very low oxygen content. The oxygen content in the discharged steam mainly comes from the escape of oxygen dissolved in the boiler feed water, and external oxygen is not suitable for mixing. Therefore, the oxygen content in the steam is very low, which is lower than the oxygen content in the flue gas and much lower 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, and can reduce the amount of reducing agent used and reduce energy consumption.

[0045] Fourth, the boiler deaerator 1 usually generates a certain amount of noise when the steam is emptied, causing environmental noise damage. However, in this embodiment, the steam of the boiler deaerator 1 is drawn out for atomization of the reducing agent, which reduces the direct discharge of steam from the boiler deaerator 1 and can effectively reduce or even eliminate the noise generated by the boiler deaerator 1 when it is emptied.

[0046] 5. The steam temperature of the boiler deaerator 1 is much higher than that of compressed air at room temperature, usually reaching above 120°C. It is used to atomize ammonia water, reduce the temperature difference between the reducing agent and the flue gas, reduce the possibility of condensation, ensure full contact between the atomized reducing agent and the flue gas, and help improve the denitrification efficiency; at the same time, it reduces the possibility of dust accumulation and corrosion and rust in the flue caused by cooling and condensation of the reducing agent.

[0047] See also Figure 2 In some embodiments of the present application, the boiler deaerator 1 includes a deaerator body 11 and an exhaust pipe 12 connected to the deaerator body 11, the exhaust pipe is provided with a first valve 13 for discharging steam, the first pipeline 4 is connected to the exhaust pipe 12, and the first pipeline 4 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 is used to discharge the excess steam generated inside the deaerator. The deaerator body 11 mostly includes two parts: a deaerator water tank and a deaerator tower. The deaerator tower is installed above the deaerator water tank, and the exhaust pipe 12 is usually installed on the top of the deaerator tower to facilitate the discharge of steam. The first valve 13 is arranged on the exhaust pipe 12. The first valve 13 is used to control the discharge amount of steam. The first valve 13 can usually adopt an automatic control valve such as an electric or start-up exhaust valve, and cooperates with a monitoring device for the working condition of the boiler deaerator 1 such as a pressure sensor to realize automatic control of boiler exhaust.

[0049] In the atomizing device of this 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. After the steam is extracted before passing through the first valve 13, the frequency and time of opening the first valve 13 can be reduced, thereby further reducing the exhaust noise of the first valve 13; on the other hand, the first valve 13 can still independently perform its exhaust function, thereby ensuring the normal working condition inside the boiler deaerator 1.

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

[0051] Compared with the previous embodiment, the second valve 14 is newly added to the exhaust pipe 12 in this embodiment, and the second valve 14 is located between the first pipeline 4 and the deaerator body 11, that is, 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 at the same time. The first pipeline 4 is used to draw out the steam of the boiler deaerator tower for atomization of the reducing agent, and the first valve 13 is used to control the emptying of the steam of the boiler deaerator tower. Therefore, the second valve 14 can simultaneously control the on-off of the steam atomization delivery and the steam emptying. The second valve 14 mainly plays a shutoff function, and a stop valve is usually used. The first pipeline 4 is connected between the first valve 13 and the second valve 14, which can reduce the frequency and time of the opening of the first valve 13 without affecting the independent emptying of the first valve 13, and can also use the second valve 14 to cut off the steam of the first pipeline 4.

[0052] See also Figure 2In some embodiments of the present application, the spray mechanism 3 includes a denitrification flue 31 and a spray gun 32 . The spray gun 32 is arranged on the denitrification flue 31 . The nozzle of the spray gun 32 faces the inside of the denitrification flue 31 . The first pipeline 4 and the second pipeline 5 are both connected to the spray gun 32 .

[0053] The spray mechanism 3 is a key device in the denitrification system. Its main function is to spray the mixed reducing agent and steam into atomized form, and then spray the atomized reducing agent into the denitrification flue 31 to react with the nitrogen oxides in the flue gas, thereby reducing the emission of nitrogen oxides. In this embodiment, the spray mechanism 3 includes a denitrification flue 31 and a spray gun 32, wherein the denitrification flue 31 is a channel for the discharge of boiler flue gas and provides 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 denitrification flue 31, and the nozzle faces the inside of the denitrification 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 denitrification flue 31, so that the atomized reducing agent is fully in contact with the flue gas, and good conditions are provided for the subsequent catalytic reduction reaction.

[0054] See also Figure 2 In some embodiments of the present application, the first pipeline 4 includes a first main pipe and multiple first branch pipes 44, the first main pipe is connected to the boiler deaerator 1, and the multiple first branch pipes 44 are all connected to the first main pipe; the second pipeline 5 includes a second main pipe 51 and multiple second branch pipes 53, the second main pipe 51 is used to input the reducing agent, and the multiple second branch pipes 53 are all connected to the second main pipe 51; the spray mechanism 3 includes multiple spray guns 32, the multiple first branch pipes 44 are connected to the multiple spray guns 32 in a one-to-one manner, and the multiple second branch pipes 53 are connected to the multiple first branch pipes 44 in a one-to-one manner.

[0055] It is preferred that a single spray gun 32 can atomize the reducing agent, and in most cases it is difficult to meet the denitration requirements of flue gas. In this embodiment, the first pipeline 4 includes a first main pipe and a plurality of first branch pipes 44. The first main pipe is the main steam delivery pipeline connecting the boiler deaerator 1 and the spray mechanism 3. It receives steam from the boiler deaerator 1 and delivers it to the plurality of first branch pipes 44. The first branch pipe 44 is a pipeline branched from the first main pipe. The number of the first branch pipes 44 is multiple, and the number is usually consistent with the number of spray guns 32, so that these first branch pipes 44 are connected to the plurality of spray guns 32 one by one, that is, each first branch pipe 44 is connected to a spray gun 32. Each first branch pipe 44 is responsible for delivering 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 pipeline for the reducing agent. It receives the reducing agent from the reducing agent storage or preparation system and delivers it to the plurality of second branch pipes 53. The second main pipe 51 can usually be provided with a delivery power device of a delivery pump 52 to provide stable power for the delivery of the reducing agent. The second branch pipe 53 is a pipe branching from the second main pipe 51. There are multiple second branch pipes 53, which are usually the same as the number of first branch pipes 44. These second branch pipes 53 are connected to multiple first branch pipes 44 in a one-to-one correspondence, that is, each second branch pipe 53 is connected to a corresponding first branch pipe 44. Each second branch pipe 53 is responsible for transporting a certain amount of reducing agent to the first branch pipe 44 connected thereto, so that the reducing agent and steam meet and fully mix in the first branch pipe 44. Each first branch pipe 44 is connected to a corresponding spray gun 32, so that the mixed reducing agent and steam are sprayed out in the denitrification flue 31 and fully mixed with the flue gas.

[0056] The first pipeline 4 branches out a plurality of first branches 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 out a plurality of second branches 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 the atomized reducing agent into the denitrification flue 31, which can ensure that sufficient and fully atomized reducing agent is sprayed into the denitrification flue 31.

[0057] See also Figure 2 In some embodiments of the present application, the denitrification flue 31 has a first inner side and a second inner side relative to each other, at least two spray guns 32 are arranged on the first inner side along the axial direction of the denitrification flue 31, and a first interval is provided between two adjacent spray guns 32 on the first inner side, and at least one spray gun 32 is arranged on the second inner side, 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, it is necessary to make the multiple spray guns 32 cooperate well with each other to achieve a good coverage effect. In the present embodiment, the denitrification flue 31 has a first inner side and a second inner side relative to each other, and spray guns 32 can be respectively arranged on the first inner side and the second inner side to spray into the denitrification 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 denitrification flue 31 (that is, the main extension direction of the flue), and a certain distance is maintained between two adjacent spray guns 32, and this distance is called the first interval. The setting of the first interval can ensure that each spray gun 32 can effectively cover its spraying area while avoiding waste caused by overlapping sprays. At least one spray gun 32 is also arranged on the second inner side. The spray direction of the second inner spray gun 32 is specifically aimed at the first interval between the two adjacent spray guns 32 on the first inner side. Such a design can make up for the area between the two adjacent spray guns 32 on the first inner side that cannot be sprayed, thereby ensuring that the spray guns 32 cover more of the internal space of the denitrification flue 31 on the basis of overlapping the spray range as much as possible. In addition, not only can the spray gun 32 on the second inner side be directed toward 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 gun 32 on the first inner side can also be directed toward the interval between the adjacent spray guns 32 on the second inner side, that is, the multiple spray guns 32 on both sides are staggered up and down, thereby reducing the overlap of the spray range and increasing the effective coverage of the spray gun 32.

[0059] In addition, there are many other specific arrangements of the multiple spray guns 32 . For example, the multiple spray guns 32 may be evenly arranged along the circumference of the denitrification flue 31 ; or the multiple spray guns 32 may be spaced apart along the axial direction of the denitrification flue 31 .

[0060] See also Figure 2 In some embodiments of the present application, a third valve 42 for adjusting the steam pressure in the first main pipe is provided on the first main pipe, and a pressure detecting component 43 for detecting the steam pressure in the first main pipe is provided on the first main pipe. The third valve 42 is communicatively connected with the pressure detecting component 43 to adjust the opening of the third valve 42 based on the pressure value detected by the pressure detecting component 43.

[0061] The third valve 42 is arranged on the first main pipe, and its main function is to adjust the steam pressure in the first main pipe, so as to ensure that the transported steam has sufficient pressure to atomize the reducing agent, and at the same time, the reducing agent will not flow back due to excessive pressure. For this reason, at the same time, a pressure detection part 43 is also installed on the first main pipe, which functions to detect the steam pressure in the first main pipe in real time. The third valve 42 can usually adopt an electric or start regulating valve, and the pressure detection part 43 can adopt a pressure gauge, a pressure sensor and other devices. The pressure detection part 43 is connected to the third valve 42 by communication, so that the opening of the third valve 42 is adjusted by the pressure value detected by the pressure detection part 43. When the pressure detection part 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 this information, the third valve 42 will automatically adjust its opening according to the preset logic. If the steam pressure is too high, the third valve 42 can slightly reduce the opening, thereby reducing the steam pressure flowing into the first main pipe; if the steam pressure is too low, the third valve 42 can increase the opening, thereby increasing the steam pressure flowing into the first main pipe. In this way, it is ensured that an appropriate pressure value is maintained in the first main pipe, thereby ensuring that the pressure value of the steam in the first branch pipe 44 is within an appropriate range.

[0062] See also Figure 2 In some embodiments of the present application, each first branch pipe 44 is respectively provided with a fourth valve 45 for adjusting the steam pressure in each first branch pipe 44 .

[0063] Although the third valve 42 can affect the steam pressure in the first branch pipe 44 by adjusting the steam pressure in the first main pipe, it cannot independently adjust the steam pressure in each first branch pipe 44. In this 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 adjusted, thereby ensuring that the steam pressure of each branch pipe reaches an appropriate value, so that 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 automatic regulating valve such as an electric or pneumatic valve, or a manual valve such as a ball valve for adjustment.

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

[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 0.25MPa, and the reducing agent pressure is equivalent to the steam pressure and slightly less than the steam pressure. The mixture of the two can achieve a good atomization effect. In addition to adjusting the pressure, the fourth valve 45 and the fifth valve 54 can actually also adjust the flow rate so that the steam flow rate and the reducing agent flow rate are compatible. For example, in some embodiments, the steam flow rate can be adjusted to 400m 3 / h, the flow rate of ammonia water as the reducing agent can be adjusted to 500L / h.

[0066] by Figure 2 For example, Figure 2 In the atomizing device in the embodiment, the first main pipe is connected between the first valve 13 and the second valve 14 of the exhaust pipe 12 of the boiler deaerator 1 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 member 43 to control the steam pressure in the first main pipe. The first main pipe is connected with four first branch pipes 44, and a fourth valve 45 is provided on each of the four first branch pipes 44 to control 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 a fifth valve 54 is provided on each of the four second branch pipes 53 to control the pressure of the reducing agent in each second branch pipe 53. The four second branch pipes 53 are connected to the four first branch pipes 44 in a one-to-one correspondence to achieve the mixing of steam and reducing agent. A total of four spray guns 32 are arranged on the denitrification flue 31, which are arranged on both sides, with two spray guns 32 on each side. The spray guns 32 on both sides are staggered up and down, and the four first branch pipes 44 are connected to the four spray guns 32 one by one to supply a mixture of steam and reducing agent to the four spray guns 32 respectively. The mixture of steam and reducing agent is sprayed from the four spray guns 32 into the denitrification flue 31 respectively, and mixed with the flue gas in the denitrification flue 31, so that the reducing agent can react with the nitrogen oxides in the flue gas under the action of the catalyst later.

[0067] Based on the above-mentioned atomizing device, the present application also provides a denitrification system, which includes the atomizing device in each of the above-mentioned embodiments. The denitrification system is used to reduce nitrogen oxides in flue gas. The principle is to inject a reducing agent into the flue gas, and under the action of a catalyst, the nitrogen oxides are reduced to harmless nitrogen and water. 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 allow the reducing agent to fully contact with the flue gas, an atomizing device can be provided in the denitrification system to atomize the reducing agent. This embodiment utilizes steam from the boiler deaerator 1 as an atomizing gas source, and the steam introduced through the first pipeline 4 is mixed with the reducing agent introduced through the second pipeline 5, and then sprayed out through the spray mechanism 3 to achieve good atomization of the reducing agent, so that it can fully contact and react with the flue gas. The denitrification system of this embodiment utilizes the steam of the boiler deaerator 1 to atomize the reducing agent of the denitrification system, thereby realizing the recovery and utilization of heat energy and achieving energy-saving effect; since the oxygen content in the steam of the boiler deaerator 1 is very low, the amount of reducing agent used can be reduced and energy consumption can be reduced; the steam of the boiler deaerator 1 is used for atomization of the reducing agent, thereby reducing the direct discharge of steam from the boiler deaerator 1 and effectively reducing the noise generated by the emptying of the boiler deaerator 1; the temperature of steam is higher than that of compressed air, thereby reducing the temperature difference between the reducing agent and the flue gas, reducing the possibility of condensation and condensation, and ensuring sufficient contact between the atomized reducing agent and the flue gas, which is beneficial to improving the denitrification efficiency; at the same time, the possibility of dust accumulation and corrosion and rust penetration in the flue caused by cooling and condensation of the reducing agent is reduced.

[0068] See also Figure 2 In some embodiments of the present application, the denitration system further includes a dust collector 6 and a denitration reactor 7 which are connected in sequence, and the spray 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 the inlet treatment equipment of the flue gas. The dust collector 6 is used to remove particulate matter in the flue gas to ensure that the flue gas entering the subsequent equipment 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 spray mechanism 3 is the spray part of the atomizing device, which can spray the reducing agent fully mixed with the steam, so that the reducing agent is fully atomized.

[0070] When the denitrification system is in operation, the flue gas will enter the dust collector 6 from the flue gas inlet, and the dust collector 6 will remove most of the particulate matter in the flue gas, making the flue gas cleaner. Then, the flue gas that has been dust-removed will enter the spray mechanism 3. The spray 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 denitrification reactor 7. In the denitrification reactor 7, the reducing agent and the nitrogen oxides in the flue gas undergo an oxidation-reduction reaction under the action of the catalyst to generate nitrogen and water, so that the nitrogen oxides in the flue gas will be removed or reduced to a level that meets environmental protection requirements, thereby realizing the denitrification treatment of the flue gas. The flue gas after denitrification is discharged from the flue gas outlet. An online flue gas analysis system is usually provided at the flue gas outlet to analyze the nitrogen oxide content in the flue gas to ensure that it meets the emission requirements.

[0071] The above are only preferred embodiments of the present application and are not intended to limit the present application. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

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

2. The atomizing device according to claim 1, characterized in that The boiler deaerator includes a deaerator body and an exhaust pipe connected to the deaerator body, the exhaust pipe is provided with a first valve for discharging steam, the first pipeline is connected to the exhaust pipe, and the first pipeline is connected between the deaerator body and the first valve.

3. The atomizing device according to claim 2, characterized in that The boiler deaerator further includes a second valve, which is disposed on the exhaust pipe and located between the first pipeline and the deaerator body.

4. The atomizing device according to claim 1, characterized in that: The spray mechanism includes a denitrification flue and a spray gun, wherein the spray gun is arranged on the denitrification flue, the nozzle of the spray gun faces the inside of the denitrification flue, and the first pipeline and the second pipeline are both connected to the spray gun.

5. The atomizing device according to claim 4, characterized in that: The first pipeline includes a first main pipe and a plurality of first branch pipes, 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 includes a second main pipe and a plurality of second branch pipes, the second main pipe is used to input the reducing agent, and the plurality of second branch pipes are all connected to the second main pipe; The spray mechanism includes a plurality of spray guns, a plurality of the first branch pipes are connected to the plurality of spray guns in a one-to-one correspondence, and a plurality of the second branch pipes are connected to the plurality of the first branch pipes in a one-to-one correspondence.

6. The atomizing device according to claim 5, characterized in that The denitrification flue has a first inner side and a second inner side relative to each other, the first inner side is provided with at least two spray guns along the axial direction of the denitrification flue, a first interval is provided between two adjacent spray guns on the first inner side, 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 according to claim 5 or 6, characterized in that: A third valve for adjusting the steam pressure in the first main pipe is provided on the first main pipe, and a pressure detection component for detecting the steam pressure in the first main pipe is provided on the first main pipe. The third valve is communicatively connected with the pressure detection component to adjust the opening of the third valve based on the pressure value detected by the pressure detection component.

8. The atomizing device according to claim 5 or 6, characterized in that: Each of the first branch pipes is respectively provided with a fourth valve for adjusting the steam pressure in each of the first branch pipes; And / or, each of the second branch pipes is respectively provided with a fifth valve for adjusting the pressure of the reducing agent in each of the second branch pipes.

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

10. The denitration system according to claim 9, characterized in that: The denitration system further comprises a dust collector and a denitration reactor which are connected in sequence, and the spray mechanism is arranged between the dust collector and the denitration reactor.

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