CN212680636U

CN212680636U - Boiler denitration integration system

Info

Publication number: CN212680636U
Application number: CN202020405090.3U
Authority: CN
Inventors: 赵虎城; 张奇; 葛立武; 张福滨; 何大海; 刘忠成; 任太琳; 何浩源; 杨先卫; 苑大磊; 周建平; 祝新普
Original assignee: Sinoma Energy Conservation Ltd
Current assignee: Chuzhou Zhongcai Energy Saving Waste Heat Power Generation Co.,Ltd.
Priority date: 2020-03-26
Filing date: 2020-03-26
Publication date: 2021-03-12
Anticipated expiration: 2030-03-26

Abstract

The utility model provides a boiler denitration integration system, including the flue, the symmetry is provided with the ammonia injection ware on the side wall of flue, the flue is inherent ammonia injection ware below top-down is provided with turbulent flow pipe, rectification grid, catalyst hoist and mount track, soot blower and catalyst module. The utility model discloses help making ammonia and nitrogen oxide fully react, strengthen the mixing effect between the flue central zone's flue gas, promote the effect of denitration.

Description

Boiler denitration integration system

Technical Field

The utility model belongs to the technical field of exhaust-heat boiler flue gas denitration, more specifically, relate to a boiler denitration integration system.

Background

Nitrogen oxides NOx (NO, NO)₂、N₂O, etc.) is one of the main atmospheric pollutants in the world, which causes environmental problems such as smog, acid rain, ozone layer destruction, etc. in the atmospheric environment, and seriously affects the living environment of human beings. Currently, there are two main ways of flue gas denitration that have been widely accepted in the world, selective non-catalytic reduction flue gas technology (SNCR) and selective catalytic reduction flue gas technology (SCR). Wherein, the SNCR method needs to be carried out under the high temperature condition of 800-1200 ℃, and the denitration efficiency is 30-60 percent; the SCR method can be carried out at the low temperature of 200-450 ℃, and the denitration efficiency can reach 80-90%. However, the two methods have the problem of ammonia escape, namely escaping ammonia gas and SO in flue gas₃Reaction to form NH₄HSO₄，NH₄HSO₄The by-products exist in a gas state at high temperature, do not block the flue, and along with the reduction of the temperature of the flue gas along the way, gaseous NH₄HSO₄Condensing into solid precipitate, and attaching to the surface of subsequent heat exchanger, blower, etc.

The utility model with the application number of 201810840509.5 provides an ammonia spraying method and an ammonia spraying system for a carbon-based catalytic desulfurization and denitrification system. The ammonia gas sprayed by the nozzle for spraying ammonia gas is horizontally arranged and the flowing direction of the sprayed ammonia gas is consistent with the flowing direction of the flue gas (downstream flow), a flue at the rear part of the nozzle is divided by a partition plate to form two flue gas channels, the flue gas channels turn to flow into a main flow flue area, no mixing part is arranged in the front channel flowing into the main flow area, the ammonia gas and the flue gas are not uniformly mixed, the flowing direction is difficult to change, and the flowing resistance is increased.

Application number is 201810931457.2's utility model discloses a SOx/NOx control integration body system, propose by device bottom side wall inflow carry out denitration treatment's integrated device again through the desulfurization, the desulfurization carries out the denitration after again and has reduced sulfur dioxide oxidation to the denitration in-process sulfur trioxide formation volume of production, but desulfurization ambient temperature is lower, and denitration ambient temperature is higher, the problem of denitration again need reheating flue gas of desulfurization earlier, and adopt horizontal arrangement denitration nozzle in the flue at the heating, the ammonia of injection forms the following current with the flue gas, can have mixed effect relatively poor, the problem that ammonia escape volume increases.

Therefore, a technical scheme which can enable ammonia gas and flue gas to be mixed more uniformly, solve the problem of ammonia gas escape and improve the denitration efficiency is urgently needed in the prior art.

SUMMERY OF THE UTILITY MODEL

Not enough to above-mentioned prior art, the utility model provides a can reduce boiler denitration integration system of ammonia escape.

In order to achieve the above purpose, the utility model discloses a following technical scheme realizes:

the utility model provides a boiler denitration integration system, includes the flue, the symmetry is provided with the ammonia injection ware on the side wall of flue, inherent in the flue the ammonia injection ware below top-down is provided with vortex pipe, rectification grid, catalyst hoist and mount track, soot blower and catalyst module.

The ammonia water ejector is positioned below the evaporator arranged in the flue.

The ammonia water injector is obliquely arranged.

The inclination angle of the ammonia water injector and the horizontal direction is 5-30 degrees.

The number of the ammonia water nozzles is at least four, and the ammonia water nozzles are symmetrically arranged along the circumferential direction of the flue side wall.

The number of the catalyst modules is at least two.

The catalyst modules are block-shaped solids placed side by side.

The catalyst module is TiO₂，V₂O₅And WO₃A mixture of (a).

Compared with the prior art, the utility model beneficial effect be:

1. 4 symmetrical ammonia water jet orifices are arranged on the side wall to form full coverage of the flow area of the flue, and ammonia water jetted by the 4 jet orifices is partially overlapped at the central position of the flue, so that ammonia gas and nitric oxide can fully react.

2. After the spraying, the ammonia water and the flue gas form partial mixing due to flowing, the mixing action among the flue gas is enhanced by adopting the turbulence pipe, a vortex flow field structure is formed behind the turbulence pipe, flow fields in different areas have velocity gradients, and the mixing action among the flue gas in the central area of the flue is enhanced.

3. Set up the rectification grid, can play the effect of eliminating the vortex flow field structure that forms behind the turbulent flow pipe, when making the inflow catalyst module, the flue gas is close at each import velocity of flow of catalyst, promotes the effect of denitration.

Drawings

Fig. 1 is a schematic structural diagram of the present invention.

Fig. 2 is a sectional view taken along line a-a of fig. 1.

FIG. 3 is a top view of the turbulence tube.

Fig. 4 is a top view of a rectifying grid.

Reference numerals: the method comprises the following steps of 1-flue, 2-evaporator, 3-ammonia injector, 4-turbulent flow pipe, 5-rectification grid, 6-catalyst hoisting track, 7-soot blower, 8-catalyst module and 9-ladder.

Detailed Description

The boiler denitration integrated system shown in fig. 1-4 comprises a flue 1, ammonia water injectors 3 are symmetrically arranged on the side walls of the flue 1, and a turbulent flow pipe 4, a rectification grid 5, a catalyst hoisting track 6, a soot blower 7 and a catalyst module 8 are arranged in the flue 1 from top to bottom below the ammonia water injectors 3.

The ammonia water injector 3 is located below the evaporator 2 disposed in the flue 1.

The ammonia injector 3 is disposed obliquely.

The inclination angle of the ammonia injector 3 to the horizontal direction is 5-30 deg. In the present embodiment, the inclination angle is 15 °.

The number of the ammonia water ejectors 3 is at least four, and the ejectors are symmetrically arranged along the circumferential direction of the side wall of the flue 1. In the present embodiment, four ammonia water injectors 3 are used, respectively arranged on the four side walls of the flue.

The number of catalyst modules 8 is at least two. In the present embodiment, the catalyst module 8 has a total of 3

The catalyst modules 8 are in the form of block-shaped solids placed side by side.

Catalyst module 8 is TiO₂，V₂O₅And WO₃A mixture of (a).

One side of flue 1 is provided with the ladder 9 that supplies the operation personnel to climb, is equipped with the shelf and the branches that are used for setting up various parts in the flue 1.

The flue gas gets into flue 1 afterbody after evaporimeter 2 is cooled down, and the flow direction is certain inclination, then the region that aqueous ammonia sprayer 3 covered of flowing through, and every aqueous ammonia sprayer 3 carries the medium jet angle and is close perpendicular with the flue gas flow direction, is 15 contained angles with the horizontal direction, forms four corners tangential circle arrangement mode to reach the interior aqueous ammonia of flue and spout full coverage, and, there is the overlap portion in flue central zone in the region that the aqueous ammonia sprays the coverage. Because the flue gas flow rate in the central area of the flue is high, the flue gas flow is large, and the flow of the carried nitrogen oxides is large, the overlapping part in the central area of the flue is beneficial to fully reacting ammonia gas and nitrogen oxides. The ammonia water concentration is 5%, the ammonia spraying amount of a single ammonia water sprayer 3 is 3kg/h, the sprayer can ensure stable and continuous ammonia water spraying and the atomization effect, and the ammonia water is decomposed into water and ammonia gas under the action of high temperature.

The turbulence pipe 4 is a row of steel pipes arranged at equal intervals and is positioned below the ammonia water injection area, the four-corner tangential structure formed by the nozzles is not damaged, and the mixture of the flue gas and the ammonia water forms a vortex flow field structure below the turbulence pipe, so that the flow time is prolonged, and the mixing effect of the flue gas and the ammonia gas is increased.

The rectification grid is located the below of turbulent flow pipe along flue gas flow direction, and single rectification grid mouth is the square of 80mm of length of a side, and the rectification grid has improved the degree of consistency that ammonia and flue gas mix, has eliminated the vortex structure that forms in the flue gas flow process behind the turbulent flow pipe, makes the flue gas velocity of flow that gets into catalyst module more even, and the mixing of ammonia and flue gas is more even, reduces the ammonia escape.

The soot blower 7 is trumpet-shaped, and the vibration of the soot blower 7 can swing ash, so that the dust is taken away by the smoke wind.

Catalyst module 8 is TiO₂，V₂O₅And WO₃The square solid formed by the mixture is hoisted and placed into the flue through a catalyst hoisting rail 6. The three catalyst modules 8 in this embodiment are placed side by side. Under the action of catalyst, NH₃With NO_X(Nitrogen oxide) reaction to form N₂And H₂And O, thereby removing nitrogen oxides in the flue gas, realizing denitration, and continuously discharging the denitrated flue gas out of the system along the flue 1.

The above description is only the preferred embodiment of the present invention, but the present invention is not limited to the above-mentioned specific embodiments, and for those skilled in the art, a plurality of modifications and improvements can be made without departing from the inventive concept of the present invention, and these modifications and improvements all belong to the protection scope of the present invention.

Claims

1. The utility model provides a boiler denitration integration system, includes flue (1), the symmetry is provided with ammonia water injector (3) on the side wall of flue (1), characterized by, flue (1) is inherent ammonia water injector (3) below top-down is provided with turbulent flow pipe (4), rectification grid (5), catalyst hoist and mount track (6), soot blower (7) and catalyst module (8).

2. The boiler denitration integrated system according to claim 1, wherein the ammonia injector (3) is located below an evaporator (2) provided in the flue (1).

3. The boiler denitration integrated system according to claim 1, wherein the ammonia injector (3) is disposed obliquely.

4. The boiler denitration integrated system according to claim 3, wherein the inclination angle of the ammonia water injector (3) to the horizontal direction is 5 to 30 °.

5. The boiler denitration integrated system according to claim 1, wherein the number of the ammonia water injectors (3) is at least four, and the ammonia water injectors are symmetrically arranged along the circumferential direction of the side wall of the flue (1).

6. The boiler denitration integrated system according to claim 1, wherein the number of the catalyst modules (8) is at least two.

7. The boiler denitration integrated system according to claim 1, wherein the catalyst modules (8) are block-shaped solids placed side by side.