Flue gas purification device for coal-fired boiler

Abstract

The utility model relates to the technical field of flue gas purification, and aims to solve the problem that the existing desulfurization device affects the discharge rate of flue gas after desulfurization. The utility model provides a flue gas purification device for a coal-fired boiler. The flue gas purification device comprises a dust removal unit, a desulfurization liquid preparation unit, a desulfurization tower and an atomization device, the desulfurization tower comprises a tower body and a plurality of tower plates; the plurality of tower plates are alternately distributed on the inner side wall of the tower body in an S shape; the bottom end of the tower body is communicated with an air inlet pipe; one end of the atomization device is communicated with the desulfurization liquid preparation unit; the other end of the atomization device penetrates into the side bottom of the tower body and extends towards the gas inlet pipe; the air inlet pipe is communicated with the dust removal unit; according to the utility model, through the plurality of tower plates which are alternately distributed in the S shape, atomized slurry and flue gas can be guided to move in the same direction, a desulfurization and dust removal path can be lengthened, the desulfurization efficiency is improved, the atomized slurry and the flue gas after desulfurization can be conveniently separated, and the discharge rate of the flue gas after desulfurization is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of flue gas purification, in particular to a flue gas purification device for a coal-fired boiler. Background Art

[0002] Coal-fired boilers are mainly used to provide superheated steam and saturated steam for each production line, which will produce a large amount of flue gas, and these flue gases need to be not only dedusted but also desulfurized. For example, the patent with publication number CN205127630U discloses a purification device for desulfurization and dust removal of flue gas from a brick kiln. Specifically, the flue gas is subjected to atomization spraying treatment for secondary dust removal. At the same time, multiple spray groups are arranged in the vertical direction to spray desulfurizer into the spray chamber to desulfurize the flue gas.

[0003] However, if multiple spray groups are vertically arranged in the spray chamber and the flue gas enters from the bottom of the spray chamber, the water mist with initial power sprayed by the multi-layer spray groups will cause the flue gas to be blocked and affect the emission rate after flue gas desulfurization. But if the flue gas enters from the top of the spray chamber, the resistance will be greater, and changing the spray direction of the spray group will affect the desulfurization effect.

[0004] Based on the above description, there is an urgent need for a coal-fired boiler flue gas purification device that is convenient for efficient desulfurization and convenient for discharge after flue gas desulfurization. Utility Model Content

[0005] The utility model aims to provide a coal-fired boiler flue gas purification device, aiming to solve the technical problem that the existing desulfurization device affects the discharge rate of flue gas after desulfurization.

[0006] The embodiments of the present invention are implemented by the following technical solutions:

[0007] A coal-fired boiler flue gas purification device comprises: a dust removal unit, a desulfurization liquid preparation unit, a desulfurization tower, and an atomization device; the desulfurization tower comprises a tower body and a plurality of tower plates; the plurality of tower plates are alternately arranged in an S shape on the inner side wall of the tower body; the bottom end of the tower body is connected with an air intake pipe; one end of the atomization device is connected with the desulfurization liquid preparation unit; the other end of the atomization device penetrates into the side bottom of the tower body and extends in the direction of the air intake pipe; the air intake pipe is connected with the dust removal unit.

[0008] Preferably, the tower plates are arc-shaped plates; and the ends of adjacent tower plates do not overlap.

[0009] Preferably, ends of adjacent tower plates partially overlap.

[0010] Preferably, a guide plate is obliquely provided at one end of the tower plate away from the air inlet pipe.

[0011] Preferably, the atomization device comprises a plurality of nozzles; the nozzles are arranged between the bottom of the tower body and the tower plate at the bottom; the nozzles extend toward the air inlet pipe.

[0012] Preferably, the desulfurization liquid preparation unit comprises a slurry tank and a liquid pump; the slurry tank is connected to the atomization device via the liquid pump.

[0013] Preferably, the bottom of the tower body is connected with a liquid extraction pipe; the liquid extraction pipe is connected with a recovery unit; and the recovery unit is connected with the pulping tank.

[0014] Preferably, an oxidation desulfurization tower is provided between the dust removal unit and the tower body.

[0015] The technical solution of the embodiment of the utility model has at least the following advantages and beneficial effects:

[0016] The utility model uses a plurality of tower plates alternately arranged in an S shape, which can not only guide the atomized slurry and the flue gas to move in the same direction, but also lengthen the desulfurization and dust removal paths, improve the desulfurization efficiency, and facilitate the separation of the atomized slurry and the flue gas after desulfurization, thereby avoiding the atomized slurry from generating resistance to the flue gas, thereby increasing the emission rate of the flue gas. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions of the embodiments of the utility model, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the utility model and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying creative work.

[0018] Figure 1 It is a schematic diagram of the pipeline system of the utility model;

[0019] Figure 2 for Figure 1 Schematic diagram of the structure of the desulfurization tower.

[0020] Icons: 1-dust removal unit, 2-desulfurization liquid preparation unit, 21-slurry making tank, 22-liquid pump, 3-desulfurization tower, 31-tower body, 32-tower plate, 4-atomization device, 41-nozzle, 5-inlet pipe, 6-guide plate, 7-liquid extraction pipe, 8-recovery unit, 81-gypsum dehydration tank, 82-sedimentation tank, 9-oxidation desulfurization tower, 10-exhaust pipe. DETAILED DESCRIPTION

[0021] Example 1

[0022] See also Figure 1 to Figure 2 The utility model provides the following technical solutions: a coal-fired boiler flue gas purification device, which is suitable for flue gas purification treatment.

[0023] Specifically, Figure 1 and Figure 2 As shown, a coal-fired boiler flue gas purification device includes: a dust removal unit 1, a desulfurization liquid preparation unit 2, a desulfurization tower 3, and an atomization device 4; the desulfurization tower 3 includes a tower body 31 and a plurality of tower plates 32; the plurality of tower plates 32 are alternately arranged in an S shape on the inner side wall of the tower body 31; the bottom end of the tower body 31 is connected with an air intake pipe 5; one end of the atomization device 4 is connected with the desulfurization liquid preparation unit 2; the other end of the atomization device 4 passes through the side bottom of the tower body 31 and extends toward the air intake pipe 5; the air intake pipe 5 is connected with the dust removal unit 1.

[0024] In this embodiment, the flue gas discharged from the boiler is preliminarily dedusted by the dust removal unit 1, wherein the dust removal unit includes a bag dust collector, and the flue gas is discharged through an induced draft fan after dust removal, and then circulated back to the bag dust collector through a blower for dust removal again. After sufficient dust removal, the flue gas is sent to the desulfurization tower 3 through the induced draft fan for desulfurization and dust removal, wherein the desulfurization tower 3 is provided with a plurality of tower plates 32 arranged alternately in an S shape, so that after the dust-removed flue gas passes into the tower body 31, it is convenient for the flue gas to move from the bottom of the tower body 31 to the top of the tower body 31 along the gap between the tower plates 32 together with the atomized slurry; through the plurality of tower plates 32 arranged alternately in an S shape, it is possible to guide the movement of the atomized slurry and the flue gas, lengthen the path of desulfurization and dust removal, improve the desulfurization efficiency, and facilitate the separation of the atomized slurry and the flue gas after desulfurization, avoid the atomized slurry from generating resistance to the flue gas, and thus improve the emission rate of the flue gas.

[0025] Specifically, Figure 2 As shown, the tower plate 32 is an arc-shaped plate; the ends of adjacent tower plates 32 do not overlap.

[0026] In this embodiment, the tail of the upper tower plate 32 and the head of the lower pedal 32 do not overlap, which makes it easier to control the directional movement of the flue gas and the atomized slurry toward the top of the tower body 31, and lengthens the flow path of the flue gas and the atomized slurry to facilitate full contact between the flue gas and the atomized slurry.

[0027] In this embodiment, the ends of the adjacent tower plates 32 can also be replaced with overlapping head and tail portions to further lengthen the desulfurization and dust removal paths and ensure the adequacy of the desulfurization and dust removal.

[0028] Specifically, Figure 2 As shown, a guide plate 6 is obliquely provided at one end of the tower plate 32 away from the air inlet pipe 5 .

[0029] The guide plate 6 facilitates the separation of the atomized slurry that settles after dust collection and reaction and the flue gas after desulfurization and dust removal. The atomized slurry that settles after dust collection and reaction is retained by the guide plate 6, and will not cause excessive resistance to the subsequent flue gas climbing up, thereby further improving the emission rate of the flue gas after desulfurization and dust removal.

[0030] Specifically, Figure 2 As shown, the atomizing device 4 includes a plurality of nozzles 41 ; the nozzles 41 are disposed between the bottom of the tower body 31 and the bottommost tower plate 32 ; the nozzles 41 extend toward the air inlet pipe 5 .

[0031] In this embodiment, the flue gas is introduced into the bottom of the tower body 31 through the induced draft fan, and the desulfurized slurry prepared in the slurry making tank 21 is input into the atomizer through the liquid pump 22, sprayed into the interior of the tower body 31 through multiple atomizing nozzles 41 and mixed with the flue gas.

[0032] In this embodiment, a gas pressure pump can be further provided before the flue gas enters the tower body 31, thereby ensuring that the flue gas has pressure when transported into the tower body 31, facilitating sufficient mixing and contact with the atomized slurry, and accelerating its discharge from the exhaust pipe 10 at the top of the tower as a whole.

[0033] Specifically, Figure 1 and Figure 2 As shown, the bottom of the tower body 31 is connected with a liquid extraction pipe 7 ; the liquid extraction pipe 7 is connected with a recovery unit 8 ; the recovery unit 8 is connected with the pulping tank 21 .

[0034] In this embodiment, the recovery unit 8 includes a gypsum dewatering tank 81 and a sedimentation tank 82. Gypsum is recovered through the gypsum dewatering tank 81, and the upper clear liquid is separated through the sedimentation tank 82 and recovered to the slurry tank 21 for mixing with limestone to prepare desulfurization slurry.

[0035] Specifically, Figure 1 As shown, an oxidation desulfurization tower 9 is provided between the dust removal unit 1 and the tower body 31 .

[0036] In this embodiment, the oxidative desulfurization tower 9 is used to introduce oxidizing air (oxygen, etc.) to perform preliminary desulfurization and buffering on the flue gas, reduce the flue gas temperature, and alleviate the desulfurization burden of the subsequent desulfurization liquid preparation unit 2.

[0037] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may be subject to various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A coal-fired boiler flue gas purification device, comprising a dust removal unit (1) and a desulfurization liquid preparation unit (2), characterized in that: It also comprises a desulfurization tower (3) and an atomization device (4); the desulfurization tower (3) comprises a tower body (31) and a plurality of tower plates (32); the plurality of tower plates (32) are arranged alternately in an S-shape on the inner side wall of the tower body (31); the bottom end of the tower body (31) is connected to an air intake pipe (5); one end of the atomization device (4) is connected to the desulfurization liquid preparation unit (2); the other end of the atomization device (4) penetrates into the side bottom of the tower body (31) and extends in the direction of the air intake pipe (5); the air intake pipe (5) is connected to the dust removal unit (1).

2. The coal-fired boiler flue gas purification device according to claim 1, characterized in that: The tower plates (32) are arc-shaped plates; the ends of adjacent tower plates (32) do not overlap.

3. The coal-fired boiler flue gas purification device according to claim 1, characterized in that: The ends of adjacent plates (32) partially overlap.

4. The coal-fired boiler flue gas purification device according to claim 2 or 3, characterized in that: A guide plate (6) is obliquely provided at one end of the tower plate (32) away from the air inlet pipe (5).

5. The coal-fired boiler flue gas purification device according to claim 3, characterized in that: The atomizing device (4) comprises a plurality of nozzles (41); the nozzles (41) are arranged between the bottom of the tower body (31) and the bottommost tower plate (32); and the nozzles (41) extend toward the air inlet pipe (5).

6. The coal-fired boiler flue gas purification device according to claim 3, characterized in that: The desulfurization liquid preparation unit (2) comprises a slurry making tank (21) and a liquid pump (22); the slurry making tank (21) is connected to the atomization device (4) via the liquid pump (22).

7. The coal-fired boiler flue gas purification device according to claim 6, characterized in that: The bottom of the tower body (31) is connected to a liquid extraction pipe (7); the liquid extraction pipe (7) is connected to a recovery unit (8); and the recovery unit (8) is connected to the pulping tank (21).

8. The coal-fired boiler flue gas purification device according to claim 3, characterized in that: An oxidation desulfurization tower (9) is provided between the dust removal unit (1) and the tower body (31).

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