CN216856249U

CN216856249U - Coal-fired pot treatment system

Info

Publication number: CN216856249U
Application number: CN202123408868.XU
Authority: CN
Inventors: 谭阳金; 汤煜佳
Original assignee: Guangdong Jbl Environmental Technology Co ltd
Current assignee: Guangdong Jbl Environmental Technology Co ltd
Priority date: 2021-12-30
Filing date: 2021-12-30
Publication date: 2022-07-01
Anticipated expiration: 2031-12-30

Abstract

A coal-fired boiler treatment system comprises a smoke dust conveying pipe, an ammonia storage tank, a gas-liquid converter, an air mixing device, a mixing cavity, an SCR reactor, a bag-type dust remover, a desulfurization device and a wet-process electric dust remover; the output end of the ammonia storage tank is connected with the input end of the gas-liquid converter, the output end of the air mixing device is connected with the input end of the mixing cavity, the output end of the SCR reactor is connected with the input end of the bag-type dust remover, the output end of the bag-type dust remover is connected with the input end of the desulfurization device, and the output end of the desulfurization device is connected with the input and output ends of the wet-process electric dust remover; the input of hybrid chamber still is provided with the output of smoke and dust conveyer pipe and connects, and this application still is provided with desulphurization unit, and desulphurization unit is current fountain desulfurizing tower, decomposes the sulphide in to waste gas through the mixed solution that is provided with injection gypsum and lime in the tower, reduces the sulphide concentration that contains in the gas, avoids the ash in the gaseous adhesion flue gas, influences the unit load.

Description

Coal-fired pot treatment system

Technical Field

The utility model relates to the technical field of waste gas treatment, in particular to a coal-fired boiler treatment system.

Background

With the stricter national environmental protection standards, the emission of NOx of a coal-fired unit is required to reach ultra-low emission (below 50mg/m 3), and the coal-fired unit mostly uses a Selective Catalytic Reduction (SCR) technology or a selective non-catalytic reduction (SNCR) + Selective Catalytic Reduction (SCR) mixed method to reach the ultra-low emission. The SCR denitration efficiency is usually over 90 percent, and a large amount of catalyst is required to be used under the requirement of high SCR denitration efficiency. It is known that the active components in the SCR catalyst promote about 1% of SO2 in the flue gas to be converted into SO3, and that the sulfur content in the coal burned by some power plants is high, SO3 generated by the combustion of the coal is high; on the other hand, high denitration efficiency requirements also easily cause that the partial ammonia escape on the outlet section of the SCR reactor is too high. High ammonia escape and high SO3 content easily generate liquid ammonium bisulfate on a heating surface of a cold end of the air preheater, the liquid ammonium bisulfate is adhered to the heating surface, ash in smoke is further adhered to cause the rapid increase of the resistance of the air preheater, and therefore, the energy consumption level of a unit is increased, and even the load of the unit is influenced.

SUMMERY OF THE UTILITY MODEL

In view of the above defects, the present invention aims to provide a coal-fired boiler treatment system, wherein a desulfurization device is added after the SCR reaction, so as to reduce the concentration of sulfide contained in the gas, and prevent the gas from adhering to ash in the flue gas to affect the load of the unit.

In order to achieve the purpose, the utility model adopts the following technical scheme: a coal-fired boiler treatment system comprises a smoke dust conveying pipe, an ammonia storage tank, a gas-liquid converter, an air mixing device, a mixing cavity, an SCR reactor, a bag-type dust remover, a desulfurization device and a wet-process electric dust remover;

the output end of the ammonia storage tank is connected with the input end of the gas-liquid converter, the output end of the gas-liquid converter is connected with the input end of an air mixing device, the output end of the air mixing device is connected with the input end of the mixing cavity, the output end of the mixing cavity is connected with the input end of the SCR reactor, the output end of the SCR reactor is connected with the input end of the bag-type dust remover, the output end of the bag-type dust remover is connected with the input end of the desulfurization device, and the output end of the desulfurization device is connected with the input and output ends of the wet-process electric dust remover;

the input end of the mixing cavity is also provided with an output end connection of a smoke dust conveying pipe.

Preferably, the air mixing device comprises a fan and a gas mixer, the output end of the fan is connected with the input end of the gas mixer, and the output end of the gas-liquid converter is connected with the input end of the gas mixer.

Preferably, a spraying grid is arranged in the mixing cavity and connected with the gas mixer.

Preferably, the device further comprises an air heater, wherein the air heater is arranged between the SCR reactor and the bag-type dust collector.

Preferably, the input end of the desulfurization device is positioned at the bottom end, the output end of the desulfurization device is positioned at the top end, and a plurality of injection interfaces are arranged on one side of the desulfurization device at intervals along the height direction of the desulfurization device;

a sewage draining outlet is formed in the bottom of the desulfurization device;

and a water outlet is also formed in one side of the desulfurization device and is positioned above the sewage draining outlet.

Preferably, the included angle α between the injection port and the outer wall of the desulfurization device is 45 °.

Preferably, one side of the desulfurization device, which is far away from the injection port, is provided with a plurality of observation windows.

Preferably, the system further comprises a compression fan, and the compression fan is arranged between the desulfurization device and the bag-type dust remover.

One of the above technical solutions has the following advantages or beneficial effects: this application still is provided with desulphurization unit, desulphurization unit is current fountain desulfurizing tower, decomposes the sulphide in to waste gas through the mixed solution that is provided with injection gypsum and lime in the tower, reduces the sulphide concentration that contains in the gas, avoids the ash in the gaseous adhesion flue gas, influences the unit load.

Drawings

FIG. 1 is a schematic structural diagram of one embodiment of the present invention;

FIG. 2 is a schematic view showing the structure of a desulfurization apparatus in one embodiment of the present invention;

fig. 3 is an enlarged view of fig. 2 at a.

Wherein: the device comprises a smoke dust conveying pipe 1, an ammonia storage tank 2, a gas-liquid converter 3, an air mixing device 4, a fan 4a, a gas mixer 4b, a mixing cavity 5, an SCR reactor 6, a bag-type dust collector 7, a desulfurization device 8, an injection interface 8a, a drain outlet 8b, a water outlet 8c, an observation window 8d, a wet-process electric dust collector 9, an injection grid 10, an air heater 11 and a compression fan 12.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the accompanying drawings are illustrative only for the purpose of explaining the present invention and are not to be construed as limiting the present invention.

In the description of the present invention, it is to be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "axial", "radial", "circumferential", and the like, indicate orientations and positional relationships based on those shown in the drawings, and are used merely for convenience of description and for simplicity of description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be considered as limiting the present invention.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless otherwise specified.

In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

As shown in fig. 1-3, a coal-fired boiler treatment system comprises a smoke dust conveying pipe (1), an ammonia storage tank (2), a gas-liquid converter (3), an air mixing device (4), a mixing cavity (5), an SCR reactor (6), a bag-type dust remover (7), a desulfurization device (8) and a wet-process electric dust remover (9);

the output end of the ammonia storage tank (2) is connected with the input end of the gas-liquid converter (3), the output end of the gas-liquid converter (3) is connected with the input end of an air mixing device (4), the output end of the air mixing device (4) is connected with the input end of the mixing cavity (5), the output end of the mixing cavity (5) is connected with the input end of the SCR reactor (6), the output end of the SCR reactor (6) is connected with the input end of the bag-type dust collector (7), the output end of the bag-type dust collector (7) is connected with the input end of the desulfurization device (8), and the output end of the desulfurization device (8) is connected with the input and output ends of the wet electric dust collector (9);

the input end of the mixing cavity (5) is also provided with an output end connection of a smoke conveying pipe (1).

The ammonia storage tank (2) stores liquid ammonia which is convenient to store relative to gaseous ammonia. The gas-liquid converter (3) can convert liquid ammonia in the ammonia storage tank (2) into gaseous ammonia, and the ammonia gas can be conveniently mixed with waste gas subsequently. The air mixing device (4) can introduce air to dilute ammonia gas. So that the ammonia concentration reaches the standard of reaction.

The mixing cavity (5) is connected with the smoke dust conveying pipe (1), the smoke dust conveying pipe (1) is connected with the coal-fired boiler, waste gas generated during combustion of the coal-fired boiler is conveyed to the mixing cavity (5) through the smoke dust conveying pipe (1), and ammonia mixed by the air mixing device (4) can also enter the mixing cavity (5). In the mixing cavity (5), ammonia gas and waste gas generated by coal combustion are fully mixed, so that the problem that the quality of SCR reaction is influenced due to uneven mixing of the waste gas and the ammonia gas when the waste gas enters the SCR reactor (6) in the subsequent weather is avoided. In the SCR reactor (6), ammonia gas and nitric oxide and nitrogen dioxide in the exhaust gas are subjected to reduction reaction, and the nitric oxide and the nitrogen dioxide are reduced into nitrogen gas. And removing nitric oxide and nitrogen dioxide in the waste gas. In this case, the exhaust gas is reduced to contain a certain amount of particulate matter or dust. Through the high-temperature-resistant cloth bag arranged in the cloth bag dust collector (7), larger particles of solid in the waste gas are filtered out through the filtration of the cloth bag. However, in this case, the exhaust gas also contains sulfides, and cannot be discharged directly into the atmosphere. So this application still is provided with desulphurization unit (8), desulphurization unit (8) are current fountain desulfurizing tower, decompose the sulphide in to the waste gas through being provided with the mixed solution that sprays gypsum and lime in the tower, reduce the sulphide concentration that contains in the gas, avoid the ash in the gaseous adhesion flue gas, influence unit load. After decomposition, nitrogen monoxide, nitrogen dioxide, nitrides and sulfides in the exhaust gas can be reduced to a certain extent. Meets the emission standard. The exhaust gas, however, also contains fine dust particles, which can affect the air. So this application is provided with at the last of system wet process electrostatic precipitator (9), through the effect of high voltage electrostatic field, collect various fine particulate matters to the collection dirt utmost point of wet process electrostatic precipitator, then rely on the mode of washing the collection dirt utmost point again to collect the dust, get rid of the dust in the gas.

Preferably, the air mixing device (4) comprises a fan (4a) and a gas mixer (4b), the output end of the fan (4a) is connected with the input end of the gas mixer (4b), and the output end of the gas-liquid converter (3) is connected with the input end of the gas mixer (4 b).

When the fan (4a) is started, air near the fan (4a) is guided into the gas mixer (4b), and then ammonia gas is introduced into the gas mixer (4 b). And diluting ammonia gas to ensure that the ammonia gas concentration reaches the standard of SCR reaction.

Preferably, a spraying grid (10) is arranged in the mixing cavity (5), and the spraying grid (10) is connected with the gas mixer (4 b).

Ammonia and exhaust gases cannot be effectively mixed if the ammonia is simply passed through the mixing chamber (5), so that the gas output to the SCR reactor (6) may be ammonia alone or exhaust gas alone, rather than a mixture of the two. Therefore, an injection grid (10) is arranged, the injection grid (10) is distributed on the top wall of the mixing cavity (5), and the output direction of the ammonia gas is sufficiently dispersed through a plurality of pipelines of the injection grid (10) so that the ammonia gas is output in each corner of the mixing cavity (5). And the delivery outlet of the injection grid (10) is smaller than that of a common pipeline, and when the gas is output, the flow velocity of the gas is faster, so that the flowing speed of the gas in the mixing cavity (5) is accelerated, and the ammonia gas and the waste gas are mixed more uniformly.

Preferably, the system further comprises an air heater (11), wherein the air heater (11) is arranged between the SCR reactor (6) and the bag-type dust collector (7).

Due to the SCR reaction, part of components in the exhaust gas are converted into solid particles, the temperature of the gas is gradually reduced in the transportation process of a pipeline between the SCR reactor (6) and the bag-type dust collector (7), and the solid particles are likely to be accumulated together to fall in the pipeline between the SCR reactor (6) and the bag-type dust collector (7) due to temperature reduction. Causing blockage of the pipeline. Set up the heater can continuously heat gas, has guaranteed gaseous velocity of flow to reduce the degree that solid particle gathers, solid particle can effectively be got rid of in sack cleaner (7) at last.

Preferably, the input end of the desulfurization device (8) is positioned at the bottom end, the output end of the desulfurization device (8) is positioned at the top end, and a plurality of injection ports (8a) are arranged on one side of the desulfurization device (8) at intervals along the height direction of the desulfurization device;

a sewage draining outlet (8b) is formed in the bottom of the desulfurization device (8);

and a water outlet (8c) is further formed in one side of the desulfurization device (8), and the water outlet (8c) is located above the sewage draining port.

Waste gas is introduced into the input end of the desulfurization device (8), waste gas is output from the output end of the desulfurization device (8), and the waste gas flows from bottom to top. The injection interface (8a) is connected with an external gypsum-lime pool, and the injection interface (8a) injects the mixed solution spray of gypsum and lime to decompose sulfides in the waste gas. The sprayed spray is contacted with the sulfide to form solution which drops on the bottom of the desulfurization device (8), after precipitation, solids can be separated out, the solids can be discharged through the sewage outlet (8b), and the liquid can be discharged into a gypsum-lime pond through the water outlet (8c) for recycling.

Preferably, the included angle α between the injection port (8a) and the outer wall of the desulfurization device (8) is 45 °.

The injection port (8a) is provided in the desulfurization device (8) at an angle of 45 DEG, and the dispersion of the spray in the horizontal direction and the vertical direction during injection can be effectively strengthened. Ensuring that the waste gas can be effectively removed to spray.

Preferably, a plurality of observation windows (8d) are arranged on one side of the desulfurization device (8) far away from the injection port (8 a).

The degree of atomization and the distribution of the spray in the desulfurization device (8) can be observed through the observation window (8 d). Ensuring the quality of the waste gas reaction.

Preferably, the system also comprises a compression fan (12), wherein the compression fan (12) is arranged between the desulfurization device (8) and the bag-type dust remover (7).

The compression fan (12) can accelerate the flowing speed of the gas, so that the waste gas has enough speed to pass through the desulphurization device (8), and the treatment speed of the waste gas is increased.

In the description herein, references to the description of the term "one embodiment," "some embodiments," "an illustrative embodiment," "an example," "a specific example," or "some examples" or the like mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the utility model. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

While embodiments of the utility model have been shown and described, it will be understood by those of ordinary skill in the art that: various changes, modifications, substitutions and alterations can be made to the embodiments without departing from the principles and spirit of the utility model, the scope of which is defined by the claims and their equivalents.

Claims

1. A coal-fired boiler treatment system is characterized by comprising a smoke dust conveying pipe (1), an ammonia storage tank (2), a gas-liquid converter (3), an air mixing device (4), a mixing cavity (5), an SCR reactor (6), a bag-type dust remover (7), a desulfurization device (8) and a wet-process electric dust remover (9);

2. A coal fired boiler treatment system according to claim 1, characterized in that the air mixing device (4) comprises a fan (4a) and a gas mixer (4b), the output of the fan (4a) is connected with the input of the gas mixer (4b), and the output of the gas-liquid converter (3) is connected with the input of the gas mixer (4 b).

3. A coal fired boiler treatment system according to claim 2, characterized in that a jet grid (10) is arranged in the mixing chamber (5), said jet grid (10) being connected to the gas mixer (4 b).

4. The coal-fired boiler treatment system according to claim 1, further comprising an air heater (11), wherein the air heater (11) is disposed between the SCR reactor (6) and the bag-type dust collector (7).

5. The coal-fired boiler treatment system according to claim 4, wherein the input end of the desulphurization device (8) is located at the bottom end, the output end of the desulphurization device (8) is located at the top end, and one side of the desulphurization device (8) is provided with a plurality of injection ports (8a) at intervals along the height direction thereof;

and a water outlet (8c) is also formed in one side of the desulfurization device (8), and the water outlet (8c) is positioned above the sewage draining outlet.

6. A coal fired boiler treatment system according to claim 5, characterized in that the angle α between the injection port (8a) and the outer wall of the desulphurization unit (8) is 45 °.

7. A coal-fired boiler treatment system according to claim 5, characterized in that the side of the desulphurization unit (8) remote from the injection port (8a) is provided with a plurality of observation windows (8 d).

8. The coal-fired boiler treatment system according to claim 5, further comprising a compression fan (12), wherein the compression fan (12) is arranged between the desulfurization device (8) and the bag-type dust collector (7).