A denitrification ammonia injection grid based on an equalizer

Abstract

The utility model discloses a denitration ammonia spraying grid based on an equalizer, including a partitioned ammonia spraying main pipe, a regulating valve and a flow meter installed on the partitioned ammonia spraying main pipe, a plurality of equalizers and connecting pipelines, and an ammonia spraying nozzle. The ammonia spraying main pipe is provided with a plurality of equalizers, the air inlet end of each equalizer is connected to the inner cavity of the ammonia spraying main pipe, and the exhaust end of each of the equalizers is connected to a plurality of ammonia spraying nozzles. The utility model adopts equalizers with multiple groups of alternating flow channels, so that each nozzle has the same flow rate and gas concentration, and the ammonia spraying amount and ammonia spraying concentration in the flue gas pipeline can be efficiently evenly distributed, and ammonia and flue gas can fully react, so as to solve the problem of incomplete ammonia spraying and denitration in large-sized flue gas pipelines and uneven flue gas distribution in the flue gas pipeline, and realize efficient denitration in the flue gas pipeline and high ammonia utilization rate.

Description

Technical Field

[0001] The utility model relates to the technical field of flue gas denitration, in particular to a denitration ammonia spraying grid based on an equalizer. Background Art

[0002] Selective catalytic reduction (SCR) denitrification technology has become the mainstream nitrogen oxide (NOx) emission reduction technology for domestic coal-fired power plants. In the denitrification system of coal-fired power plants, SCR denitrification technology has been widely used. Its principle is to spray ammonia into the flue, and react with nitrogen oxides (mainly nitric oxide, NO) in the flue gas under the action of a catalyst to generate harmless nitrogen and water vapor. This process can effectively reduce pollutants emitted by coal-fired power plants and protect the environment.

[0003] However, in actual applications, the denitrification devices of coal-fired power plants face some challenges. For example, the flue gas volume usually reaches millions of cubic meters per hour, and the cross-sectional area of ​​the flue is more than 100 square meters. In this case, the distribution of ammonia spraying is often uneven, with more ammonia sprayed in some areas and less ammonia sprayed in some areas. This leads to uneven mixing of the reactants (ammonia and nitrogen oxides) in the flue. If the reactants are not mixed evenly, the overall denitrification efficiency will be affected. In order to solve this problem, the H-type ammonia spray grid is currently commonly used, which can improve the uniformity of ammonia spraying to a certain extent, but due to the inherent characteristics of the H-type ammonia spray grid (the nozzle resistance far away from the inlet is large and the flow rate is small), the problem of ammonia spraying uniformity cannot be solved. Utility Model Content

[0004] The utility model provides a denitration and ammonia injection grid based on an equalizer, which aims to solve the above-mentioned problems existing in the prior art.

[0005] In order to achieve the above-mentioned purpose, the utility model provides a denitrification ammonia injection grid based on an equalizer, including a partitioned ammonia injection main pipe, a regulating valve and a flow meter installed on the partitioned ammonia injection main pipe, a plurality of equalizers and connecting pipelines, and an ammonia injection nozzle. A plurality of equalizers are arranged on the ammonia injection main pipe, and the air inlet end of each equalizer is connected to the inner cavity of the ammonia injection main pipe, and the exhaust end of each of the equalizers is connected to a plurality of ammonia injection nozzles.

[0006] In the above technical solution, the cross section in the flue is evenly divided into a plurality of ammonia injection zones, and an ammonia injection grid is correspondingly arranged in each ammonia injection zone.

[0007] In the above technical solution, the outer end of each ammonia injection main pipe passes through the side wall of the flue and extends to the outside of the flue to be connected to the ammonia-air mixer.

[0008] In the above technical solution, the jetting direction of each nozzle is the same as the gas flow direction in the flue.

[0009] In the above technical solution, the equalizer includes an inlet pipe and two forked outlet pipes sealed and connected to the exhaust end of the inlet pipe. The inner cavity of the outlet pipe is divided into a plurality of flow channels by a plurality of partitions. The flow channels are alternately connected. The end of each forked outlet pipe is connected to the exhaust pipe. One end of the exhaust pipe is sealed and connected to the forked outlet pipe, and the other end is closed. An exhaust hole is opened on the side wall of the exhaust pipe and is connected to a nozzle.

[0010] In the above technical solution, the regulating valve and the flow meter are electrically connected through a circuit.

[0011] In the above technical solution, the number of the alternately arranged flow channels is 4 to 20.

[0012] In the above technical solution, the spoiler tubes are arranged below the alternately arranged flow channels, and the number of the spoiler tubes corresponds one-to-one to the alternately arranged and connected flow channels.

[0013] In the above technical solution, preferably, the cross section of the spoiler tube is circular.

[0014] In the above technical solution, the number of the equalizers is 2 n -1, where n is an integer ≥ 2.

[0015] The utility model provides a denitration ammonia spraying grid based on a uniform distributor, which has the following beneficial effects:

[0016] The utility model adopts multiple groups of dividers with alternating flow channels, so that each nozzle has the same flow rate and gas concentration. The amount and concentration of ammonia sprayed in the flue gas duct can be efficiently and evenly distributed, and ammonia and flue gas can fully react, thereby solving the problem of incomplete denitrification caused by uneven distribution of flue gas in large-sized flue gas ducts and flue gas ducts, thereby achieving efficient denitrification in the flue gas duct and high utilization rate of ammonia. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The drawings constituting a part of the present invention are used to provide a further understanding of the present invention, so that other features, purposes and advantages of the present invention become more obvious. The drawings and descriptions of the schematic embodiments of the present invention are used to explain the present invention and do not constitute an improper limitation on the present invention. In the drawings:

[0018] Figure 1 It is a schematic cross-sectional view of the overall structure of the utility model.

[0019] Figure 2 It is a schematic diagram of the three-dimensional structure of the utility model equalizer.

[0020] Figure 3 It is a top view schematic diagram of the structure of the equalizer of the utility model.

[0021] Figure 4For the utility model Figure 3 AA cross-sectional view of .

[0022] Figure 5 For the utility model Figure 3 BB cross-sectional view.

[0023] Reference numerals:

[0024] 1- ammonia injection main pipe;

[0025] 2- regulating valve;

[0026] 3- Flow meter;

[0027] 4-divider; 41-inlet pipe; 42-outlet pipe; 421-partition plate; 4210-flow channel;

[0028] 5- spoiler tube;

[0029] 6- Nozzle;

[0030] 7- Exhaust pipe;

[0031] 100-smoke duct; 101-ammonia spraying partition; DETAILED DESCRIPTION

[0032] In order to enable those skilled in the art to better understand the solution of the utility model, the technical solution in the embodiment of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiment of the utility model. Obviously, the described embodiment is only a part of the embodiment of the utility model, not all of the embodiments. Based on the embodiment of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the utility model.

[0033] It should be noted that the terms "first", "second", etc. in the specification and claims of the utility model and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so as to describe the embodiments of the utility model described here. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0034] In the present invention, the terms "upper", "lower", "left", "right", "front", "back", "top", "bottom", "inside", "outside", "middle", "vertical", "horizontal", "lateral", "longitudinal" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings. These terms are mainly used to better describe the present invention and its embodiments, and are not used to limit the indicated devices, elements or components to have a specific orientation, or to be constructed and operated in a specific orientation.

[0035] In addition, some of the above terms may be used to express other meanings in addition to indicating orientation or positional relationship. For example, the term "on" may also be used to express a certain dependency or connection relationship in some cases. For those skilled in the art, the specific meanings of these terms in this utility model can be understood according to specific circumstances.

[0036] In addition, the term "plurality" shall mean two or more.

[0037] It should be noted that, in the absence of conflict, the embodiments and features of the embodiments of the present invention can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0038] Embodiment 1:

[0039] Please see attached Figure 1-5 The present embodiment provides a denitrification ammonia injection grid based on an equalizer, comprising a partitioned ammonia injection main pipe 1, a regulating valve 2 and a flow meter 3 installed on the partitioned ammonia injection main pipe 1, a plurality of equalizers 4 and connecting pipelines, and an ammonia injection nozzle 6. A plurality of equalizers 4 are arranged on the ammonia injection main pipe 1, and the air inlet end of each equalizer 4 is connected to the inner cavity of the ammonia injection main pipe 1, and the exhaust end of each of the equalizers 4 is connected to the ammonia injection nozzle.

[0040] In the above embodiment, multiple groups of dividers with alternating flow channels are used to make each nozzle have the same flow rate and gas concentration, and the amount and concentration of ammonia sprayed in the flue gas duct can be efficiently and evenly distributed, so that ammonia and flue gas can fully react, thereby solving the problem of incomplete ammonia denitrification caused by uneven flue gas distribution in large-sized flue gas ducts and flue gas ducts, thereby achieving efficient denitrification in flue gas ducts and high ammonia utilization rate.

[0041] In the above embodiments, please refer to the attached Figure 1 The cross section of the flue 100 is evenly divided into a plurality of ammonia injection zones 101 , and an ammonia injection grid is correspondingly arranged in each ammonia injection zone 101 .

[0042] In the above embodiments, please refer to the attached Figure 1The outer end of each ammonia injection main pipe 1 extends through the side wall of the flue 100 to the outside of the flue 100 and is connected to an ammonia-air mixer. The ammonia-air mixer provides an ammonia-air mixture in the ammonia injection pipeline, specifically about 5% ammonia and 95% air.

[0043] In the above embodiment, the jetting direction of each nozzle is the same as the gas flow direction in the flue 100 .

[0044] In the above embodiments, please refer to the attached Figure 2-5 The divider 4 includes an inlet pipe 41 and two bifurcated outlet pipes 42 which are sealed and connected to the exhaust end of the inlet pipe 41. The inner cavity of one of the outlet pipes 42 is divided into seven flow channels by six partitions 421, wherein the flow channels 1, 3, 5, and 7 are connected, and the tail ends of the flow channels 4210 of 2, 4, and 6 are closed by setting a baffle. The inner cavity of the other outlet pipe 42 is divided into seven flow channels by six partitions 421, wherein the flow channels 2, 4, and 6 are connected, and the tail ends of the flow channels 4210 of 1, 3, 5, and 7 are closed by setting a baffle. The end of each bifurcated outlet pipe 42 is connected to the exhaust pipe 7, one end of the exhaust pipe 7 is sealed and connected to the bifurcated outlet pipe 42, and the other end is closed. The exhaust gas at the outlet end of the flow channel 4210 is gathered in the exhaust pipe 7 for mixing. Since it is an alternately connected flow channel, there is a pressure difference in the exhaust pipe 7 for a better mixing effect. The side wall of the exhaust pipe is provided with an exhaust hole and connected to the nozzle 5. The multiple sets of alternately connected flow channel structures are designed to divide the gas into two, similar to the differential principle, to ensure that the gas flow rate and concentration of a1 and a2 are close or the same after the diversion. The equalizer 4 adopts a structure of multiple sets of alternately connected flow channels, which theoretically realizes the equal distribution of the ammonia injection amount and the equal distribution and remixing of the ammonia injection concentration. Among them, one ammonia injection mother pipe 1 corresponds to more than 16 ammonia injection nozzles, and each nozzle has the same flow rate and concentration, so as to realize the uniform distribution of the ammonia gas in the partition.

[0045] In the above embodiments, please refer to the attached Figure 1 Each partition is provided with an ammonia injection main pipe 1 and a flow meter 3, and the ammonia injection amount can be independently controlled according to demand. The regulating valve 2 and the flow meter 3 are electrically connected through a circuit.

[0046] In the above embodiment, the number of the alternately arranged flow channels is 4 to 20, preferably 8.

[0047] In the above embodiment, the spoiler tubes are arranged at the rear ends of the alternately arranged through flow channels, and the number of the spoiler tubes corresponds one to one with the alternately arranged flow channels.

[0048] In the above embodiments, please refer to the attached Figure 4 , 5 , the cross section of the spoiler tube is circular.

[0049] In the above embodiment, the number of the dividers 4 is 2n -1, where n is an integer ≥ 2.

[0050] The above description is only the preferred embodiment of the utility model, and is not intended to limit the utility model. For those skilled in the art, the utility model can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the utility model shall be included in the protection scope of the utility model.

Claims

1. A denitration ammonia injection grid based on a distributor, characterized in that: It includes a partitioned ammonia injection main pipe, a regulating valve and a flow meter installed on the partitioned ammonia injection main pipe, a plurality of equalizers and connecting pipelines, and an ammonia injection nozzle. A plurality of equalizers are arranged on the ammonia injection main pipe, and the air inlet end of each equalizer is connected to the inner cavity of the ammonia injection main pipe, and the exhaust end of each of the equalizers is connected to a plurality of ammonia injection nozzles.

2. A denitration ammonia injection grid based on a distributor as claimed in claim 1, characterized in that: The cross section in the flue is evenly divided into a plurality of ammonia injection zones, and an ammonia injection grid is correspondingly arranged in each ammonia injection zone.

3. The denitration ammonia injection grid based on a distributor according to claim 1, characterized in that: The outer end of each ammonia injection main pipe passes through the side wall of the flue and extends to the outside of the flue to be connected with the ammonia-air mixer.

4. The denitration ammonia injection grid based on a distributor according to claim 1, characterized in that: The jetting direction of each nozzle is the same as the gas flow direction in the flue.

5. The denitration ammonia injection grid based on a distributor according to claim 1, characterized in that: The divider includes an inlet pipe and two forked outlet pipes sealed and connected to the exhaust end of the inlet pipe. The inner cavity of each outlet pipe is divided into a plurality of flow channels by a plurality of partitions. The flow channels are alternately connected. The end of each forked outlet pipe is connected to the exhaust pipe. One end of the exhaust pipe is sealed and connected to the forked outlet pipe, and the other end is closed. An exhaust hole is provided on the side wall of the exhaust pipe and is connected to a nozzle.

6. The denitration ammonia injection grid based on a distributor according to claim 1, characterized in that: The regulating valve and the flow meter are electrically connected via an electric circuit.

7. A denitration ammonia injection grid based on a distributor as claimed in claim 6, characterized in that: The number of alternately arranged flow channels is 4 to 20.

8. The denitration ammonia injection grid based on a distributor as claimed in claim 5, characterized in that: The spoiler pipes are arranged at the rear ends of the alternately arranged flow channels, and the number of the spoiler pipes corresponds one to one to the alternately arranged and connected flow channels.

9. A denitration ammonia injection grid based on a distributor as claimed in claim 8, characterized in that: The cross section of the spoiler tube is circular.

10. The denitration ammonia injection grid based on a distributor according to claim 6, characterized in that: The number of the equalizers is 2 n -1, where n is an integer ≥ 2.

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