Inlet flue structure of wet desulfurization tower

Abstract

The utility model discloses a wet desulfurization tower inlet flue structure which comprises a desulfurization tower, a concentration tower outlet flue and a desulfurization raw flue gas flue, the desulfurization raw flue gas flue is communicated with the desulfurization tower inlet flue, the desulfurization tower inlet flue extends into the desulfurization tower, the concentration tower outlet flue is communicated with the desulfurization raw flue gas flue, and the concentration tower outlet flue is communicated with the desulfurization raw flue gas flue. The concentration tower outlet flue and the desulfurization raw flue gas flue form a communicating channel with a downward leakage structure, or a blocking structure positioned in front of and / or behind the concentration tower outlet flue is arranged in the desulfurization raw flue gas flue. Condensate water in the flue gas at the outlet of the concentration tower does not enter the inlet flue of the desulfurization tower, so that the corrosion probability of the inlet flue of the desulfurization tower is reduced; extreme working condition desulfurization slurry can be discharged into the concentration tower outlet flue through a branch pipe of the concentration tower outlet flue, or blocked through a blocking structure to protect a booster fan or an induced draft fan; and the flow field uniformity of the outlet (namely the section of the joint with the desulfurizing tower) of the inlet flue of the desulfurizing tower can be improved by more than 10%.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of flue gas desulfurization, and particularly relates to a wet desulfurization tower inlet flue structure. BACKGROUND

[0002] The limestone-gypsum wet flue gas desulfurization technology is mature, has high desulfurization efficiency, and can comprehensively utilize the desulfurization byproducts, and is widely applied in industrial flue gas SO2 removal projects. However, a certain amount of desulfurization wastewater is generated in the desulfurization process, and if the wastewater is directly discharged without proper treatment, it will cause serious pollution to water bodies and soil. The traditional desulfurization wastewater treatment often adopts a triple-box treatment technology, that is, through pre-sedimentation, neutralization, precipitation and flocculation, the suspended solids, heavy metals and part of COD and other pollutants in the desulfurization wastewater are removed. The technical route commonly used for the "zero discharge" of the desulfurization wastewater is to first concentrate and reduce the amount of the desulfurization wastewater, and then use the high-temperature bypass flue gas before the air preheater to dry and evaporate the wastewater after the concentration and reduction. In the technical route, part of the flue gas with a temperature of 100-140 DEG C after the dust remover and before the desulfurization tower is usually extracted into the concentration tower, the desulfurization wastewater is sprayed into the concentration tower, most of the water in the wastewater is evaporated by the flue gas, and then the flue gas is discharged from the top of the concentration tower, and the flue gas is collected into the desulfurization tower inlet flue through the concentration tower outlet flue, mixed with the flue gas after the induced draft fan, and then enters the desulfurization tower for desulfurization.

[0003] The technology provides a low-energy-consumption, small-land-occupancy and simple-operation-maintenance way for the zero discharge of the desulfurization wastewater, but there are problems such as poor uniformity of the flue gas flow field at the desulfurization tower inlet, corrosion of the desulfurization tower inlet flue by the condensed water of the flue gas after the concentration tower, and corrosion of the induced draft fan by the backflow of the desulfurization slurry. CONTENT OF THE UTILITY MODEL

[0004] The application aims to provide a wet desulfurization tower inlet flue structure, which adopts a desulfurization wastewater concentration tower outlet flue with a down-in type and a multi-channel flow collection, or adopts a desulfurization raw flue gas flue with a front and rear water-blocking blocking structure matched with the desulfurization tower inlet flue structure, so as to prevent the corrosion of the desulfurization tower inlet flue by the condensed water of the desulfurization wastewater concentration tower outlet flue, avoid the corrosion of the booster fan or the induced draft fan by the backflow of the desulfurization slurry, and improve the uniformity of the flue gas flow field at the desulfurization tower inlet.

[0005] The purpose of the application is achieved by the following technical scheme:

[0006] A wet desulfurization tower inlet flue structure, comprising a desulfurization tower, a concentration tower outlet flue and a desulfurization raw flue gas flue, the desulfurization raw flue gas flue is communicated with the desulfurization tower inlet flue, the desulfurization tower inlet flue extends into the desulfurization tower, the concentration tower outlet flue is communicated with the desulfurization raw flue gas flue, the concentration tower outlet flue and the desulfurization raw flue gas flue form a communication channel with a down-leak structure, or the desulfurization raw flue gas flue is provided with a blocking structure located in front of and / or behind the concentration tower outlet flue.

[0007] Further, the outlet flue of the concentration tower extends below the desulfurization raw flue gas flue, and the outlet flue of the concentration tower is communicated with the bottom of the desulfurization raw flue gas flue through at least two branch pipes.

[0008] Further, the bottom of the outlet flue of the concentration tower is provided with a blowdown valve.

[0009] Further, the branch pipes are arranged uniformly or non-uniformly along the width direction of the desulfurization raw flue gas flue.

[0010] Further, the outlet flue of the concentration tower and the branch pipes are rectangular or circular in cross section.

[0011] Further, the desulfurization tower inlet flue and the desulfurization raw flue gas flue are rectangular in cross section.

[0012] Further, the flue width of the desulfurization tower inlet flue is 0.7-0.85 times the diameter of the desulfurization tower.

[0013] Further, the desulfurization tower inlet flue is arranged in a downward inclination from front to back.

[0014] Further, the inclination angle of the desulfurization tower inlet flue is 10°-20°.

[0015] Further, the desulfurization raw flue gas flue is arranged horizontally.

[0016] Further, the front end of the desulfurization raw flue gas flue is provided with a booster fan or an induced draft fan.

[0017] Compared with the direct entry of the outlet flue gas of the concentration tower into the side of the desulfurization raw flue gas flue, the condensed water in the outlet flue gas of the concentration tower does not enter the desulfurization tower inlet flue, reducing the corrosion probability of the desulfurization tower inlet flue; in addition, when the desulfurization slurry enters the desulfurization tower inlet flue or even the desulfurization raw flue gas flue in extreme working conditions, the desulfurization slurry can be discharged into the concentration tower outlet flue through the branch pipes of the concentration tower outlet flue, or be blocked by the blocking structure, protecting the booster fan or the induced draft fan; compared with the direct entry of the outlet flue gas of the concentration tower into the side of the desulfurization raw flue gas flue, the arrangement of the branch pipes on the concentration tower outlet flue and the entry of the desulfurization raw flue gas flue from the ground can make the flow field uniformity of the outlet of the desulfurization tower inlet flue (i.e. the cross section of the connection with the desulfurization tower) increase by more than 10%.

[0018] The foregoing main scheme of the present application and each further selected scheme thereof can be freely combined to form multiple schemes, all of which are the schemes that can be adopted and claimed by the present application; and the present application can also be freely combined between (each non-conflicting selection) and between other selections. Those skilled in the art can understand that there are multiple combinations according to the prior art and common knowledge after understanding the present scheme, and all of them are the technical schemes claimed by the present application, which will not be listed here. BRIEF DESCRIPTION OF DRAWINGS

[0019] Fig. 1 is the main view of the structure of the present application.

[0020] Fig. 2 is the side view of the structure of the present application.

[0021] Fig. 3 is the top view of the structure of the present application.

[0022] In the figure: 1 - desulfurization tower, 2 - desulfurization tower inlet flue, 3 - concentration tower outlet flue, 4 - branch pipe, 5 - desulfurization raw flue gas flue. DETAILED DESCRIPTION

[0023] The present application will be further described below in conjunction with specific embodiments and the accompanying drawings.

[0024] Example 1

[0025] Reference Figs. 1-3 As shown in the figure, a wet desulfurization tower inlet flue structure includes a desulfurization tower 1, a desulfurization tower inlet flue 2, a concentration tower outlet flue 3, and a desulfurization raw flue gas flue 5, and further includes a branch pipe 4 or a blocking structure.

[0026] The desulfurization raw flue gas flue 5 is in communication with the desulfurization tower inlet flue 2, the desulfurization tower inlet flue 2 extends into the desulfurization tower 1 (middle and lower region), the concentration tower outlet flue 3 is in communication with the desulfurization raw flue gas flue 5, the concentration tower outlet flue 3 and the desulfurization raw flue gas flue 5 form a communication passage of a lower leakage structure, or the desulfurization raw flue gas flue 5 is provided with a blocking structure located in front of and / or behind the concentration tower outlet flue 3.

[0027] That is, the present embodiment adopts two ways: first, the communication passage of the lower leakage structure is used to realize the collection of liquid leakage, so as to remove the liquid in the raw flue gas flue, to avoid the condensed water in the outlet flue gas of the concentration tower from entering the desulfurization tower inlet flue, to avoid the corrosion problem of the inlet flue, and to avoid the backflow of the desulfurization slurry or condensed water to the fan at the front end of the raw flue gas flue.

[0028] Second, the blocking structure is used to realize the high-position blocking of the liquid, so as to block the forward and backward flow of the liquid in the raw flue gas flue, to avoid the condensed water in the outlet flue gas of the concentration tower from entering the desulfurization tower inlet flue, to avoid the corrosion problem of the inlet flue, and to avoid the backflow of the desulfurization slurry or condensed water to the fan at the front end of the raw flue gas flue.

[0029] For the first way, the concentration tower outlet flue 3 is preferably introduced from the side and extends below the desulfurization raw flue gas flue 5, and the concentration tower outlet flue 3 is in communication with the bottom of the desulfurization raw flue gas flue 5 through at least two branch pipes 4, that is, the branch pipe 4 serves as the communication passage of the lower leakage structure.

[0030] The bottom of the outlet flue 3 of the concentration tower is provided with a blowdown valve, and the outlet flue is regularly drained through the blowdown valve. The branch pipes 4 are uniformly or non-uniformly arranged along the width direction of the desulfurized raw flue gas flue 5, and uniform arrangement is conducive to improving the uniformity of the flow field at the gas mixing place. The outlet flue 3 of the concentration tower and the branch pipes 4 are rectangular or circular in cross section.

[0031] For the second mode, the desulfurized raw flue gas flue 5 is directly communicated with the side bottom of the outlet flue 3 of the concentration tower, and a baffle is arranged in the desulfurized raw flue gas flue 5 as a blocking structure. The baffle can be a vertical baffle or an inclined slope plate. The baffle is fixed in front of and behind the outlet flue 3 of the concentration tower to achieve a water blocking effect.

[0032] For the two modes, the desulfurized tower inlet flue 2 and the desulfurized raw flue gas flue 5 are rectangular in cross section. The flue width of the desulfurized tower inlet flue 2 is 0.7-0.85 times the diameter of the desulfurized tower. The desulfurized tower inlet flue 2 is arranged downwardly from front to back, and the inclination angle of the desulfurized tower inlet flue 2 is 10°-20°, so that the desulfurized tower inlet flue 2 itself has a certain counterflow effect. The desulfurized raw flue gas flue 5 is horizontally arranged, and the front end of the desulfurized raw flue gas flue 5 is provided with a booster fan or an induced draft fan.

[0033] The working process of the present application: when the system is running, the flue gas in the desulfurization wastewater concentration tower is discharged through the outlet flue 3 of the concentration tower, and the outlet flue gas of the concentration tower enters the desulfurized raw flue gas flue 5 through the outlet flue 3 of the concentration tower (the first mode also includes the branch pipe 4) in turn, and then enters the desulfurized tower 1 through the desulfurized tower inlet flue 2 to carry out desulfurization reaction. The condensed water in the outlet flue 3 of the concentration tower remains in the outlet flue of the concentration tower or the desulfurized raw flue gas flue 5, and a blowdown valve can be provided at the low part of the outlet flue of the concentration tower or the desulfurized raw flue gas flue for regular discharge of condensed water.

[0034] Example 2

[0035] Taking a 660MW coal-fired unit limestone-gypsum wet desulfurization project as an example, the flue gas amount after the induced draft fan of the project is 2316697Nm 3 / h (standard wet state, the same below), of which 250000Nm 3 / h flue gas extraction into desulfurization wastewater concentration tower, the rest of the flue gas through the induced draft fan outlet flue into the desulfurization original flue gas flue. Desulfurization tower inlet flue cross section is rectangular, the angle of inclination is 10°-20°, connecting the desulfurization original flue gas flue and desulfurization tower. Desulfurization original flue gas flue cross section is also rectangular, horizontal arrangement, connecting induced draft fan outlet flue and desulfurization tower inlet flue. Desulfurization tower inlet flue and desulfurization original flue gas flue cross section width is 14800mm, height is 4750mm. Concentration tower outlet flue is circular flue, diameter 2500mm, from the left side of desulfurization original flue gas flue access to desulfurization original flue gas flue below, concentration tower outlet flue is provided with 3 round branch pipe connecting desulfurization original flue gas flue, branch pipe diameter is 1500mm, branch pipe spacing is 5000mm, and the middle branch pipe is arranged on the center line of desulfurization original flue gas flue.

[0036] System operation, flue gas from induced draft fan through induced draft fan outlet flue into desulfurization original flue gas flue, flue gas from desulfurization wastewater concentration tower through concentration tower outlet flue from the left side of desulfurization original flue gas flue into desulfurization original flue gas flue below, then through the 3 round branch pipe provided in concentration tower outlet flue into desulfurization original flue gas flue, mixed with flue gas from induced draft fan, mixed flue gas through desulfurization tower inlet flue into desulfurization tower for desulfurization.

[0037] The flue structure scheme proposed in the embodiment, at the desulfurization tower inlet flue outlet (i.e. the section connected with the desulfurization tower), the relative deviation of flue gas flow rate is 15%, compared with the direct entry of flue gas from the concentration tower outlet into the desulfurization original flue gas flue from the side, the relative deviation of flue gas flow rate is reduced by 10%. The relative humidity in the flue gas from the concentration tower outlet is relatively high, and condensate is usually generated in the flue during long distance transportation. The use of the lower inlet type mixing branch pipe can ensure that the condensate in the concentration tower outlet flue does not enter the desulfurization tower inlet flue, thereby reducing the corrosion probability of the desulfurization tower inlet flue. In addition, when the desulfurization tower appears extreme working conditions, part of the desulfurization slurry enters the desulfurization tower inlet flue or even the desulfurization original flue gas flue, the desulfurization slurry can also flow into the concentration tower outlet flue through the branch pipe of the concentration tower outlet flue, thereby avoiding the desulfurization slurry flowing to the induced draft fan and causing corrosion of the induced draft fan.

[0038] Other same as embodiment 1.

[0039] The foregoing basic examples and each further selected example of the present application can be freely combined to form a plurality of embodiments, all of which are embodiments that can be used and claimed by the present application. In the present application scheme, each selected example can be arbitrarily combined with any basic example and selected example.

[0040] The above only describes the preferred embodiments of the present application and is not intended to limit the present application. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A wet desulphurization tower inlet flue structure comprising a desulphurization tower (1), a concentration tower outlet flue (3) and a desulphurized raw flue gas flue (5), characterized by: The desulfurization original flue gas flue (5) is communicated with the desulfurization tower entrance flue (2), the desulfurization tower entrance flue (2) extends to the desulfurization tower (1), the concentration tower outlet flue (3) is communicated with the desulfurization original flue gas flue (5), the concentration tower outlet flue (3) and the desulfurization original flue gas flue (5) form the communication passage of lower leakage structure, or the desulfurization original flue gas flue (5) is equipped with the blocking structure located in the front and / or rear of the concentration tower outlet flue (3).

2. The wet desulphurization tower inlet flue structure according to claim 1, characterized in that: The concentration tower outlet flue (3) extends to the lower of the desulfurization original flue gas flue (5), and the concentration tower outlet flue (3) is communicated with the bottom of the desulfurization original flue gas flue (5) by at least two branch pipes (4).

3. The wet desulphurization tower inlet flue structure according to claim 2, characterized in that: The bottom of the concentration tower outlet flue (3) is equipped with a blowdown valve.

4. A wet desulphurisation tower inlet flue arrangement according to claim 2 or 3, characterised in that: The branch pipe (4) is evenly or unevenly arranged along the width direction of the desulfurization original flue gas flue (5).

5. The wet desulphurization tower inlet flue structure according to claim 2, characterized in that: The concentration tower outlet flue (3) and the branch pipe (4) are rectangular or circular cross section.

6. The wet desulphurization tower inlet flue structure according to claim 1, characterized in that: The desulfurization tower entrance flue (2) and the desulfurization original flue gas flue (5) are rectangular cross section.

7. The wet desulphurization tower inlet flue structure according to claim 1 or 6, characterized in that: The flue width of the desulfurization tower entrance flue (2) is 0.7-0.85 times of the diameter of the desulfurization tower.

8. The wet desulphurization tower inlet flue gas duct structure according to claim 1, characterized in that: The desulfurization tower entrance flue (2) is arranged in a downward inclination from front to back.

9. The wet desulphurization tower inlet flue structure according to claim 8, characterized in that: The inclination angle of the desulfurization tower entrance flue (2) is 10-20°.

10. A wet desulphurisation tower inlet flue arrangement according to claim 1, 8 or 9, characterised in that: The desulfurization original flue gas flue (5) is horizontally arranged, and the front end of the desulfurization original flue gas flue (5) is equipped with a booster fan or an induced draft fan.

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