CN217340821U

CN217340821U - Flue gas denitration system

Info

Publication number: CN217340821U
Application number: CN202123202383.5U
Authority: CN
Inventors: 代维鑫
Original assignee: Beijing Yangde Environmental Protection And Energy Technology Co ltd
Current assignee: Beijing Yangde Environmental Protection And Energy Technology Co ltd
Priority date: 2021-12-20
Filing date: 2021-12-20
Publication date: 2022-09-02
Anticipated expiration: 2031-12-20

Abstract

The utility model relates to a SCR flue gas denitration system technical field under the well low temperature condition, concretely relates to flue gas denitration system. The embodiment of the utility model provides a flue gas denitration system includes denitration reactor, a plurality of boiler and a plurality of urea spray gun. The urea spray gun is correspondingly connected to the front end of one boiler, the boilers are arranged in parallel through pipelines, and the pipelines are arranged at the rear ends of the boilers and communicated with the denitration reactor. The utility model provides a flue gas denitration system before arranging the urea spray gun in the boiler, denitration reactor places behind the boiler, has realized high-temperature pyrolysis, well low temperature reaction, has both reduced the running cost, has protected the catalyst again, improves flue gas denitration system's life.

Description

Flue gas denitration system

Technical Field

The utility model relates to a SCR flue gas denitration system technical field under the well low temperature condition, concretely relates to flue gas denitration system.

Background

Nitrogen oxides are main pollutants in the atmosphere and can cause serious harm to human health, ecological environment and social production activities, so that the nitrogen oxides contained in the flue gas are allowed to be discharged after being purified. With the increasing attention of human beings on environmental protection, the importance of the process of removing nitrogen oxides from flue gas and preventing environmental pollution has become a worldwide sharp problem. At present, the most mainstream denitration technology in the world is a selective catalytic reduction technology, namely an SCR denitration technology. The SCR is divided into low-temperature, medium-low temperature, medium-temperature and high-temperature catalysts according to the characteristics of the catalyst of the core part of the SCR, and a denitration process is required to be selected in a targeted manner according to the actual situation on site.

The gas generator set has the characteristics of high exhaust temperature and large flue gas fluctuation, and the stable long-term operation of the system is determined by the selection of the SCR denitration process. The exhaust temperature of a gas generator set can reach 550-650 ℃, the gas generator set enters a denitration reactor without being cooled, and even a high-temperature catalyst cannot bear the high-temperature catalyst (the general service life and temperature resistance range of the high-temperature catalyst is 400-600 ℃), the actual service life of the high-temperature catalyst is possibly short for one year, and the high cost of the catalyst cannot cause frequent replacement. The difficulty is increased and the load of the boiler is greatly increased due to the need of reducing excessive temperature of the low-temperature SCR. Medium and low temperature SCR denitration is most suitable for being applied to a gas generator set, and how to combine medium and low temperatures into a whole and meet the temperature difference in winter and summer at the same time becomes a plurality of difficulties.

SUMMERY OF THE UTILITY MODEL

The utility model discloses (one) the technical problem that solve is: how to combine the medium and low temperature into one and simultaneously meet the temperature difference problem in winter and summer.

(II) technical scheme

In order to solve the technical problem, an embodiment of the utility model provides a flue gas denitration system, which comprises a denitration reactor, a plurality of boilers and a plurality of urea spray guns;

the urea spray gun is correspondingly connected to the front end of one boiler, the boilers are arranged in parallel through pipelines, and the pipelines are arranged at the rear ends of the boilers and communicated with the denitration reactor.

According to the utility model discloses an embodiment, every the rear end of boiler with be provided with between the pipeline and all be provided with the solenoid valve.

According to the utility model discloses an embodiment, every the front end and the rear end of boiler are connected with a three-way control valve, three-way control valve's first opening with the urea spray gun intercommunication, three-way control valve's second opening with the front end intercommunication of boiler, three-way control valve's third opening with the rear end intercommunication of boiler.

According to the utility model discloses an embodiment, spare catalyst layer, first catalyst layer and second catalyst layer have set gradually in the denitration reactor.

According to the utility model discloses an embodiment, be provided with pressure differential transmitter on the denitration reactor, pressure differential transmitter's a port set up in the place ahead of reserve catalyst layer, another port of pressure differential transmitter set up in the rear of second catalyst layer.

According to the utility model discloses an embodiment, the pipeline pass through the flue gas hybrid tube with the denitration reactor is connected.

According to the utility model discloses an embodiment, be provided with the flue gas flowmeter on the pipeline.

According to an embodiment of the present invention, the pipeline is provided with a nitrogen oxide detector.

According to the utility model discloses an embodiment, be connected with the thermocouple on the denitration reactor.

According to the utility model discloses an embodiment, flue gas deNOx systems still includes the solenoid valve controller, the solenoid valve controller with the solenoid valve is connected, is used for control opening or closing of solenoid valve.

The utility model has the advantages that: the embodiment of the utility model provides a flue gas denitration system includes denitration reactor, a plurality of boiler and a plurality of urea spray gun. The urea spray gun is correspondingly connected to the front end of one boiler, the boilers are arranged in parallel through pipelines, and the pipelines are arranged at the rear ends of the boilers and communicated with the denitration reactor. The urea spray gun is arranged in front of the boiler, and the denitration reactor is arranged behind the boiler, so that high-temperature pyrolysis and medium-low-temperature reaction are realized, the operation cost is reduced, the catalyst is protected, and the service life of a flue gas denitration system is prolonged. In addition, the aim of reducing emission of nitrogen oxides in the tail gas can be achieved on the premise of solving the complex smoke working condition of the gas generator set.

Drawings

The above and/or additional aspects and advantages of the present invention will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:

fig. 1 is a schematic view of a flue gas denitration system according to an embodiment of the present invention;

fig. 2 is the embodiment of the utility model provides an in the embodiment denitration reactor of flue gas denitration system's schematic diagram.

Wherein, the corresponding relations between the reference numbers and the part names in fig. 1 to fig. 2 are as follows:

1. the denitration reactor comprises a generator, 2, a denitration reactor, 21, a standby catalyst layer, 22, a first catalyst layer, 23, a second catalyst layer, 3, a boiler, 4, a urea spray gun, 5, a pipeline, 6, an electromagnetic valve, 7, a three-way regulating valve, 8, a pressure difference transmitter, 9, a flue gas mixing pipe, 10, a flue gas flowmeter, 11 and a nitrogen oxide detector.

Detailed Description

In order to make the aforementioned objects, features and advantages of the present invention more clearly understood, the present invention will be described in further detail with reference to the accompanying drawings and detailed description. It should be noted that the embodiments and features of the embodiments of the present application may be combined with each other without conflict.

As urea can be completely pyrolyzed at the temperature of more than 350 ℃, the moderate temperature range of the medium-low temperature catalyst is 220-380 ℃, and the reaction can not be efficiently pyrolyzed in a certain range, the reductant urea needs to be excessively sprayed, and the operation cost is increased.

As shown in fig. 1 and 2, in order to solve the above problem, an embodiment of the present invention provides a flue gas denitration system, which includes a denitration reactor 2, a plurality of boilers 3 and a plurality of urea spray guns 4.

The urea spray gun 4 is correspondingly connected to the front end of the boiler 3, the boilers 3 are arranged in parallel through a pipeline 5, and the pipeline 5 is arranged at the rear end of the boiler 3 and communicated with the denitration reactor 2.

The utility model provides a flue gas denitration system arranges urea spray gun 4 in boiler 3 before, and denitration reactor 2 is placed after boiler 3, has realized high-temperature pyrolysis, well low temperature reaction, has both reduced the running cost, has protected the catalyst again, improves flue gas denitration system's life.

In one embodiment, optionally, a solenoid valve 6 is disposed between the rear end of each boiler 3 and the pipeline 5.

Furthermore, the front end and the rear end of each boiler 3 are connected with a three-way regulating valve 7, a first opening of the three-way regulating valve 7 is communicated with the urea spray gun 4, a second opening of the three-way regulating valve 7 is communicated with the front end of the boiler 3, and a third opening of the three-way regulating valve 7 is communicated with the rear end of the boiler 3.

In the embodiment, a bypass parallel connection mode of the boiler 3 is adopted, and a three-way regulating valve 7 is arranged on a pipeline 5 of the boiler, so that the flue gas temperature regulation and control in winter and summer can be realized. For example, the second opening and the third opening on the boiler 3 side are fully open, the first opening is fully closed, and the smoke temperature is lowest; the second opening and the third opening of 3 sides of boiler are full-open, and the first opening is full-open, and the gas temperature is the highest, adjusts the aperture between the two, can the preceding temperature of meticulous control denitration reactor 2. Meanwhile, a thermocouple is further connected to the denitration reactor 2. By combining the display of the thermocouple, the smoke temperature can be accurately controlled, and the aims of protecting the catalyst and efficiently reacting are fulfilled. In addition, a flue gas butterfly valve with tight sealing is additionally arranged after an outlet of the boiler 3 is converged with a pipeline 5 of the three-way regulating valve 7, then a plurality of boilers 3 are merged and converged into the pipeline 5 and then enter the denitration reactor 2, and the outlet is emptied into the atmosphere.

As shown in fig. 2, in one embodiment, a spare catalyst layer 21, a first catalyst layer 22 and a second catalyst layer 22 are optionally disposed in the denitration reactor 2 in sequence. Thus, the denitration effect in the denitration reactor 2 can be improved. Can meet the environmental protection requirement in a limited way and achieve the effect of reducing the emission of nitrogen oxides.

In one embodiment, optionally, a pressure difference transmitter 8 is disposed on the denitration reactor 2, one port of the pressure difference transmitter 8 is disposed in front of the spare catalyst layer 21, and the other port of the pressure difference transmitter 8 is disposed behind the second catalyst layer 22. The differential pressure change is monitored by the arrangement of the differential pressure transmitter 8.

In one embodiment, the pipeline 5 is connected to the denitration reactor 2 through a flue gas mixing pipe 9. Optionally, a flue gas flow meter 10 is arranged on the pipeline 5. And the real-time monitoring of the flue gas flow is realized.

Further, in order to monitor the content of carbon oxides in real time, a nitrogen oxide detector 11 is provided on the pipe 5.

In the above embodiment, the flue gas flowmeter 10 is additionally provided, the accurate content of nitrogen oxides is calculated by measuring the real-time flue gas flow and according to the previous nitrogen-oxygen value, the required amount of urea is accurately calibrated by the molar ratio of ammonia nitrogen to nitrogen under reaction, so that accurate injection is achieved, and the influence caused by the load change of a single generator 1 is avoided. Is more suitable for the all-in-one gas generator 1 group.

In addition, flue gas denitration system still includes 6 controllers of solenoid valve, 6 controllers of solenoid valve with solenoid valve 6 is connected for control 6 opens or closes of solenoid valve.

It will be appreciated that, in order to simplify the control logic, the all-in-one device adopts the mode of urea injection amount total amount control, namely adjusting the injection total amount and evenly dividing the flow of the plurality of urea spray guns 4, and only needs to reach the required ammonia total amount before the reaction. A unit start-stop interlocking solenoid valve 6 is added at the inlet of a single urea spray gun 4, when the unit is shut down, the control solenoid valve 6 is closed, the original quartering of the total amount is changed into trisection, the total amount of urea is unchanged, and the phenomenon that single path cannot be pyrolyzed due to shutdown is avoided.

In any of the above embodiments, the boiler 3 is the hot air exhaust-heat boiler 3, and can be put into operation to exhaust hot air even in summer without heating, thereby avoiding the water treatment process of the steam boiler 3.

To sum up, the embodiment of the utility model provides a flue gas denitration system includes denitration reactor 2, a plurality of boiler 3 and a plurality of urea spray gun 4. The urea spray gun 4 is correspondingly connected to the front end of the boiler 3, the boilers 3 are arranged in parallel through a pipeline 5, and the pipeline 5 is arranged at the rear end of the boiler 3 and communicated with the denitration reactor 2. Before arranging the urea spray gun 4 in the boiler 3, the denitration reactor 2 is arranged behind the boiler 3, so that high-temperature pyrolysis and medium-low temperature reaction are realized, the operation cost is reduced, the catalyst is protected, and the service life of a flue gas denitration system is prolonged. In addition, the aim of reducing the emission of nitrogen oxides in the tail gas can be achieved on the premise of solving the complex smoke working condition of the gas generator 1 group. Through accurate urea injection control, under the condition of all-in-one, the influence of the working condition of a single generator 1 group is avoided, and waste of redundant urea is avoided to the utmost extent while high-efficiency denitrification is realized. The whole set of flue gas denitration system is simple and convenient to operate and is suitable for different conditions in heating seasons and non-heating seasons.

In the description of the present invention, it should be noted that the terms "upper", "lower", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, which are only for convenience of description and simplification of description, but do not indicate or imply that the device or element referred to must have a specific orientation, be constructed in a specific orientation, and be operated, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the description of the present invention, it is to be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; the communication may be direct, indirect via an intermediate medium, or internal to both elements. The specific meaning of the above terms in the present invention can be understood in specific cases to those skilled in the art. In addition, in the description of the present invention, "a plurality" means two or more unless otherwise specified.

The above description is only for the preferred embodiment of the present invention, and is not intended to limit the present invention, and any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention should be included within the protection scope of the present invention.

Claims

1. The utility model provides a flue gas denitration system which characterized in that: the device comprises a denitration reactor, a plurality of boilers and a plurality of urea spray guns;

2. The flue gas denitration system of claim 1, wherein: and an electromagnetic valve is arranged between the rear end of each boiler and the pipeline.

3. The flue gas denitration system of claim 2, wherein: the front end and the rear end of each boiler are connected with a three-way regulating valve, a first opening of each three-way regulating valve is communicated with the urea spray gun, a second opening of each three-way regulating valve is communicated with the front end of each boiler, and a third opening of each three-way regulating valve is communicated with the rear end of each boiler.

4. The flue gas denitration system of claim 1, wherein: a standby catalyst layer, a first catalyst layer and a second catalyst layer are sequentially arranged in the denitration reactor.

5. The flue gas denitration system of claim 4, wherein: and a pressure difference transmitter is arranged on the denitration reactor, one port of the pressure difference transmitter is arranged in front of the standby catalyst layer, and the other port of the pressure difference transmitter is arranged behind the second catalyst layer.

6. The flue gas denitration system according to any one of claims 1 to 5, wherein: the pipeline is connected with the denitration reactor through a flue gas mixing pipe.

7. The flue gas denitration system of claim 6, wherein: and a flue gas flowmeter is arranged on the pipeline.

8. The flue gas denitration system of claim 6, wherein: and a nitrogen oxide detector is arranged on the pipeline.

9. The flue gas denitration system of claim 6, wherein: and the denitration reactor is connected with a thermocouple.

10. The flue gas denitration system of claim 6, wherein: the electromagnetic valve control device is connected with the electromagnetic valve and used for controlling the opening or closing of the electromagnetic valve.