CN209885581U

CN209885581U - Be applied to SCR flue gas denitration's reductant mixing arrangement

Info

Publication number: CN209885581U
Application number: CN201920650409.6U
Authority: CN
Inventors: 郑妍; 韩晨; 唐坚; 赵喆; 姚宣; 李晓金; 劳俊
Original assignee: Beijing Guodian Longyuan Environmental Engineering Co Ltd
Current assignee: Guoneng Longyuan Environmental Protection Co Ltd
Priority date: 2019-05-08
Filing date: 2019-05-08
Publication date: 2020-01-03
Anticipated expiration: 2029-05-08

Abstract

A reducing agent mixing device applied to SCR flue gas denitration; comprises an inlet flue and an SCR reactor; the inlet flue is of an S-shaped structure, a filter screen is inserted into the left end of the inlet flue, a rectangular discharge port is formed in the bottom of the left end of the inlet flue, a material collecting box is magnetically connected to the bottom of the discharge port, an ammonia spraying device is arranged in the middle of the inlet flue, serpentine vortex tubes are arranged below the inlet flue and at the bending part of the upper portion of the inlet flue, the right end of the inlet flue is communicated with the top of the SCR reactor, and three catalyst layers are longitudinally arranged inside the SCR reactor; the utility model can not only avoid the blocking of the inlet flue, but also realize the sufficient mixing of the flue gas and the reducing agent by utilizing the mutual matching between the two serpentine vortex tubes and the ammonia spraying device, thereby ensuring the uniformity of the downstream flow field; furthermore, the utility model discloses simple structure, simple to operate can realize the effect that better reductant and flue gas mix.

Description

Be applied to SCR flue gas denitration's reductant mixing arrangement

Technical Field

The utility model relates to a thermal power factory flue gas SCR denitration technical field, concretely relates to be applied to SCR flue gas denitration's reductant mixing arrangement.

Background

The mainstream methods of the flue gas denitration technology of the thermal power generating unit are Selective Catalytic Reduction (SCR) and selective non-catalytic reduction (SNCR). The SCR technology is widely applied due to higher denitration efficiency, and the principle is that in the temperature range of 300-400 ℃, a reducing agent (ammonia) is sprayed into a flue to be fully mixed with flue gas, a downstream denitration reactor is carried out, and Nitrogen Oxide (NOX) in the flue gas is removed under the catalytic action of a catalyst to generate nitrogen and water.

Compared with the amount of flue gas, the injection amount of the reducing agent is small, and meanwhile, the section of the flue is large, so that the flue gas and the reducing agent are difficult to be fully mixed, the uniformity of inlet flow fields of a denitration reactor and a catalyst is poor, and the denitration effect is influenced. Especially for the actual engineering with extremely high denitration efficiency, the mixing effect of the reducing agent and the flue gas directly influences the removal effect of the nitrogen oxides.

The existing reducing agent mixing device usually adopts a grid and other distribution devices, and because the caliber of a nozzle is small, the existing reducing agent mixing device is easy to block under the condition of high concentration of flue gas fly ash, and the operation of a system is influenced; moreover, the reducing agent and the flue gas cannot be fully mixed, and the treatment effect on the flue gas is influenced. Meanwhile, the ammonia injection grid has poor adaptability to the inflow of flue gas under the condition of variable load of the boiler, so that the requirement on the operation of an SCR denitration system is difficult to meet.

SUMMERY OF THE UTILITY MODEL

The shortcoming to flue gas mixing arrangement among the current SCR deNOx systems, the utility model aims at providing a novel reductant mixing arrangement, can not only avoid the entry flue to block up, can also make the reductant spout back in the flue, realize the intensive mixing of reductant and flue gas, improve the adaptability of mixing arrangement to the boiler variable load simultaneously.

The utility model discloses a following technical scheme realizes:

a reducing agent mixing device applied to SCR flue gas denitration comprises an inlet flue and an SCR reactor; the inlet flue is of an S-shaped structure, a filter screen is inserted into the left end of the inlet flue, a rectangular discharge port is formed in the bottom of the left end of the inlet flue, a material collecting box is magnetically connected to the bottom of the discharge port, an ammonia spraying device is arranged in the middle of the inlet flue, snake-shaped vortex tubes are arranged below the inlet flue and at the bending position of the upper portion of the inlet flue, the right end of the inlet flue is communicated with the top of the SCR reactor, and three catalyst layers are longitudinally arranged inside the SCR reactor.

Furthermore, a rectangular insertion groove is formed in the top of the left end portion of the inlet flue, the bottom of the rectangular insertion groove is communicated with the inlet flue, and the thickness value of the filter screen is equal to the width value of the rectangular insertion groove.

Furthermore, the inner wall on the right side of the rectangular discharge hole is longitudinally coplanar with the left end part of the filter screen.

Furthermore, the outside of rectangle discharge gate inlays and is equipped with "returning" type magnet strip, the top of the case that gathers materials also inlays and is equipped with "returning" type magnet strip, and two magnet strips are the magnetic pole of synonym each other.

Furthermore, the material collecting box is made of light plastic, and a handle is arranged at the bottom of the material collecting box.

Furthermore, the ammonia injection device is arranged between the two serpentine vortex tubes.

Furthermore, an exhaust pipe is arranged at the bottom of the SCR reactor and communicated with an external air suction pump.

Furthermore, the ammonia spraying device comprises a liquid inlet pipe and a spray head, the spray head is arranged at the right end part of the liquid inlet pipe, and the spray head is arranged in the inlet flue.

The utility model has the advantages that:

the utility model aims at providing a novel reducing agent mixing device, which not only can avoid the blockage of an inlet flue, but also can realize the sufficient mixing of the flue gas and the reducing agent by utilizing the mutual matching between two serpentine vortex tubes and an ammonia spraying device, thereby ensuring the uniformity of a downstream flow field; because the position of the standing vortex is unchanged when the standing vortex changes along with the incoming flow of the flue gas, the mixing effect cannot be changed when the unit is under the load-variable working condition, and the self-adaptive capacity is strong, so that the automatic adjustment of the unit can be realized when the load is variable; and the number of the spray pipes is small, the caliber is large, the blockage is not easy to occur, and the workload of overhauling and maintaining is reduced. Furthermore, the utility model discloses simple structure, simple to operate can realize the effect that better reductant and flue gas mix.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.

Fig. 1 is a schematic view of a first perspective structure of the present invention;

FIG. 2 is a schematic longitudinal sectional view of the present invention;

fig. 3 is a schematic view of a second perspective structure of the present invention;

FIG. 4 is an enlarged schematic view of a portion of the left end of the inlet flue of the present invention;

fig. 5 is a schematic structural diagram of a serpentine vortex tube according to the present invention.

In the figure: 1-inlet flue, 2-SCR reactor, 3-filter screen, 4-rectangular discharge port, 5-material collecting box, 6-ammonia spraying device, 7-snake vortex tube, 8-catalyst layer, 9-magnet bar, 10-handle, 11-exhaust pipe, 12-liquid inlet pipe, 13-spray head.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative efforts belong to the protection scope of the present invention.

A reducing agent mixing device applied to SCR flue gas denitration comprises an inlet flue 1 and an SCR reactor 2; entry flue 1 is S type structure, and its left end portion is pegged graft and is had filter screen 3, rectangle discharge gate 4 has been seted up to the bottom of 1 left end portion of entry flue, the bottom magnetism of discharge gate is connected with the case 5 that gathers materials, the middle part of entry flue 1 is equipped with spouts ammonia device 6, the below of entry flue 1 and the department of bending on its upper portion all are equipped with snakelike vortex tube 7, the right-hand member portion of entry flue 1 is linked together with SCR reactor 2 'S top, SCR reactor 2' S inside vertically is equipped with three-layer catalyst layer 8.

Specifically, a rectangular insertion groove is formed in the top of the left end of the inlet flue 1, the bottom of the rectangular insertion groove is communicated with the inlet flue 1, and the thickness value of the filter screen is equal to the width value of the rectangular insertion groove; the inner wall of the right side of the rectangular discharge port 4 is longitudinally coplanar with the left end part of the filter screen; the outer side of the rectangular discharge port 4 is embedded with a 'return' type magnet strip 9, the top of the material collecting box 5 is also embedded with the 'return' type magnet strip 9, and the two magnet strips are of different magnetic poles; the material collecting box 5 is made of light plastic, and the bottom of the material collecting box 5 is provided with a handle 10; the ammonia spraying device 6 is arranged between the two serpentine vortex tubes 7; an exhaust pipe 11 is arranged at the bottom of the SCR reactor 2, and the exhaust pipe 11 is communicated with an external air pump; the ammonia spraying device 6 comprises a liquid inlet pipe 12 and a spray head 13, the spray head 13 is arranged at the right end part of the liquid inlet pipe 12, and the spray head 13 is arranged in the inlet flue 1.

When handling the flue gas, make the flue gas in the entry flue 1 slowly take out to SCR reactor 2 through the use of external aspiration pump, at the in-process of bleeding, the flue gas passes through the filter screen 3 of entry flue 1 left end portion earlier, under the filtration of filter screen 3, and the solid tiny particle/dust in the flue gas finally falls to the case 5 that gathers materials, will gather materials case 5 and take off through the handle 10 of manual pulling case 5 bottom that gathers materials to the solid particle who will gather materials in the case 5 pours out. So that the occurrence of a blockage of the inlet flue 1 can be avoided. The material collecting box 5 is connected with the inlet flue 1 through the 'return' type magnet strip 9, so that the sealing performance is better. Moreover, the material collecting box 5 is convenient and quick to mount and dismount. The filter screen is inserted in the inlet flue 1, and the installation and the disassembly are also simpler and more convenient. The flue gas flows into the serpentine vortex tube 7 positioned below after being filtered by the filter screen 3, is discharged after being forcedly disturbed in the serpentine vortex tube 7, and is uniformly sprayed by a reducing agent (available reducing agent forms comprise ammonia gas, urea pyrolysis products and urea hydrolysis products) in the spray header 13, so that the flue gas and the reducing agent are mixed for the first time. The two are mixed and pumped into the snake-shaped vortex tube 7 at the bent part at the upper part of the inlet flue 1 under the action of the air pump, so that secondary forced turbulence is realized, and multiple forced mixing of the reducing agent and the flue gas is ensured. Finally, the two are uniformly mixed and then enter the SCR reactor 2 together, nitrogen oxides in the flue gas are removed under the action of catalysts on three catalyst layers 8 in the SCR reactor 2, and finally, the clean flue gas is discharged from an exhaust pipe 11 at the bottom of the SCR reactor 2, so that the clean emission of the flue gas is realized.

The utility model has the advantages that the flue gas and the reducing agent are fully mixed by utilizing the mutual matching between the two serpentine vortex tubes 7 and the ammonia spraying device 6, and the uniformity of a downstream flow field is ensured; because the position of the standing vortex is unchanged when the standing vortex changes along with the incoming flow of the flue gas, the mixing effect cannot be changed when the unit is under the load-variable working condition, and the self-adaptive capacity is strong, so that the automatic adjustment of the unit can be realized when the load is variable; and the number of the spray pipes is small, the caliber is large, the blockage is not easy to occur, and the workload of overhauling and maintaining is reduced. Furthermore, the utility model discloses simple structure, simple to operate can realize the effect that better reductant and flue gas mix.

The applicant states that the present invention is illustrated by the above examples, and the present invention is not limited to the above detailed structural features and methods, i.e. the present invention can be implemented only by relying on the above detailed structural features and methods. It should be clear to those skilled in the art that any improvement of the present invention is to the equivalent replacement of the selected parts of the present invention and the addition of auxiliary parts, the selection of specific modes, etc., all fall within the scope of protection and disclosure of the present invention.

It should be noted that, in the above embodiments, the described specific technical features can be combined in any suitable manner without contradiction, and in order to avoid unnecessary repetition, the present invention does not need to describe the possible combinations.

Claims

1. A reducing agent mixing device applied to SCR flue gas denitration comprises an inlet flue and an SCR reactor; the method is characterized in that: the inlet flue is of an S-shaped structure, a filter screen is inserted into the left end of the inlet flue, a rectangular discharge port is formed in the bottom of the left end of the inlet flue, a material collecting box is magnetically connected to the bottom of the discharge port, an ammonia spraying device is arranged in the middle of the inlet flue, snake-shaped vortex tubes are arranged below the inlet flue and at the bending position of the upper portion of the inlet flue, the right end of the inlet flue is communicated with the top of the SCR reactor, and three catalyst layers are longitudinally arranged inside the SCR reactor.

2. The reducing agent mixing device applied to SCR flue gas denitration of claim 1, characterized in that: the top of the left end part of the inlet flue is provided with a rectangular insertion groove, the bottom of the rectangular insertion groove is communicated with the inlet flue, and the thickness value of the filter screen is equal to the width value of the rectangular insertion groove.

3. The reducing agent mixing device applied to SCR flue gas denitration of claim 1, characterized in that: the inner wall on the right side of the rectangular discharge port is longitudinally coplanar with the left end part of the filter screen.

4. The reducing agent mixing device applied to SCR flue gas denitration of claim 1, characterized in that: the outside of rectangle discharge gate is inlayed and is equipped with "returning" type magnet strip, the top of case that gathers materials also inlays and is equipped with "returning" type magnet strip, and two magnet strips are the magnetic pole of synonym each other.

5. The reducing agent mixing device applied to SCR flue gas denitration of claim 1, characterized in that: the material collecting box is made of light plastic, and a handle is arranged at the bottom of the material collecting box.

6. The reducing agent mixing device applied to SCR flue gas denitration of claim 1, characterized in that: the ammonia spraying device is arranged between the two serpentine vortex tubes.

7. The reducing agent mixing device applied to SCR flue gas denitration of claim 1, characterized in that: and an exhaust pipe is arranged at the bottom of the SCR reactor and is communicated with an external air suction pump.

8. The reducing agent mixing device applied to SCR flue gas denitration of claim 1, characterized in that: the ammonia spraying device comprises a liquid inlet pipe and a spray head, the spray head is arranged at the right end part of the liquid inlet pipe, and the spray head is arranged in the inlet flue.