A circulating fluidized bed flue gas purification system and its integrated connection device

Abstract

The present invention relates to a circulating fluidized bed flue gas purification system and an integrated connection device thereof, wherein the integrated connection device comprises a bag dust collector and a flue; an air inlet is arranged at the top of the bag dust collector, and an air outlet is arranged at the bottom of the bag dust collector, the air inlet is connected with the exhaust port of a desulfurization reaction tower of the circulating fluidized bed flue gas purification system, and the air outlet is connected with a denitrification reaction tower of the circulating fluidized bed flue gas purification system through the flue; the front end of the flue is connected with the air outlet in a vertical direction, so that the overall occupied space of the circulating fluidized bed flue gas purification system can be reduced, so that the possibility of overall arrangement of the circulating fluidized bed flue gas purification system is improved within a limited site space, and the flue gas emission requirements are met.

Description

Technical Field

[0001] The invention relates to the technical field of flue gas equipment, and in particular to a circulating fluidized bed flue gas purification system and an integrated connection device thereof. Background Art

[0002] The circulating fluidized bed flue gas purification system consists of a desulfurization reaction tower, a bag filter, a denitrification reaction tower, a material circulation system, an absorbent preparation and supply system, a flue gas system, a process water system, a fluidized air system, etc. The main process production devices and auxiliary facilities are centrally arranged around the desulfurization reaction tower according to the process requirements, among which the desulfurization reaction tower, the bag filter, and the denitrification reaction tower are arranged in sequence.

[0003] The outlet flue gas of the desulfurization reaction tower is filtered by the bag filter and then enters the denitrification reaction tower along the flue. Since the temperature of the filtered flue gas is usually around 70-100°C, and the flue gas entering the denitrification reaction tower often needs to reach a target temperature of around 230-280°C (medium and low temperature denitrification), the filtered flue gas needs to be heated by the GGH flue gas heat exchanger and the heating furnace to reach the target temperature before entering the denitrification reaction tower.

[0004] The dust-laden flue gas should flow in the same direction as the flue gas into the denitrification reactor, that is, vertically downward. In this way, the dust can be easily removed and carried away by the flue gas without accumulating on the catalyst. If the flue gas flows upward, the dust is affected by gravity and may still hang in the reactor after cleaning and is not easily carried away by the flue gas. In the end, it still adheres to the catalyst, causing the system resistance to increase. Therefore, the flue gas must enter the denitrification reactor from the top and flow vertically downward.

[0005] like Figure 1 As shown, in the prior art, a bag filter 01 and a flue 02 are connected between the desulfurization reaction tower 03 and the denitration reaction tower 04, and the front end of the flue 02 (the end facing the upstream of the airflow) is connected to the air outlet cavity 011 in the bag filter 01 from the side wall of the bag filter 01, and then turns downward and heats the internal flue gas to make it reach the flue gas temperature required by the denitration reaction tower 04. Such a setting can make the flue 02 form three horizontal sections 021 and two vertical sections 022 between the bag filter 01 and the denitration reaction tower 04, and there is a turning point between two adjacent horizontal sections 021 and vertical sections 022, occupying a large space. In actual engineering applications, compact plant areas are often encountered, and the site is extremely limited. There is no space for each system to be arranged in sequence, and it is impossible to arrange a complete flue gas purification system.

[0006] Therefore, how to optimize the overall occupied space of the circulating fluidized bed flue gas purification system so as to improve the possibility of arranging the circulating fluidized bed flue gas purification system in sequence within the limited site space to meet the flue gas emission requirements is a technical problem that needs to be urgently solved by technical personnel in this field. Summary of the invention

[0007] The purpose of the present invention is to provide a circulating fluidized bed flue gas purification system and an integrated connection device thereof, which can reduce the overall occupied space of the circulating fluidized bed flue gas purification system, thereby increasing the possibility of arranging the circulating fluidized bed flue gas purification system in sequence within a limited site space and meeting the flue gas emission requirements.

[0008] In order to solve the above technical problems, the present invention provides an integrated connection device for a circulating fluidized bed flue gas purification system, which includes a bag dust collector and a flue; an air inlet is provided at the top of the bag dust collector, and an air outlet is provided at the bottom of the bag dust collector, the air inlet is connected to the exhaust port of the desulfurization reaction tower of the circulating fluidized bed flue gas purification system, and the air outlet is connected to the denitrification reaction tower of the circulating fluidized bed flue gas purification system through the flue; the front end of the flue is connected to the air outlet in the vertical direction.

[0009] The air inlet of the bag-type dust collector is arranged at the top, and the air outlet is arranged at the bottom, instead of being led out from the side wall of the bag-type dust collector. With this arrangement, the exhaust port of the desulfurization reaction tower can be connected with the bag-type dust collector through a vertically arranged flue gas pipe, and the front end of the flue can be directly led downward from the air outlet in a vertical direction. In other words, the flue gas pipe or flue connected to the bag-type dust collector is arranged in a vertical direction, and there is no need to set a bend at the air outlet of the flue.

[0010] The flue includes a first vertical section, a first horizontal section, a second vertical section and a second horizontal section which are connected in sequence, i.e., two vertical sections and two horizontal sections, wherein the first vertical section is connected to the air outlet of the bag filter, and the rear end of the second horizontal section is connected to the denitration reaction tower. Compared with the solution in which the air outlet of the bag filter is arranged on the side, a horizontal section arranged between the flue and the denitration reaction tower can be reduced, thereby shortening the longitudinal arrangement distance of the device (from the desulfurization reaction tower to the denitration reaction tower), thereby reducing the overall occupied space of the circulating fluidized bed flue gas purification system, thereby improving the possibility of overall arrangement of the circulating fluidized bed flue gas purification system within a limited site space.

[0011] Moreover, such an arrangement can reduce the number of bending sections, thereby making the flue gas flow line smooth and the flow field uniform, which is beneficial for the denitration catalyst in the denitration reaction tower to fully contact with the flue gas, thereby improving the denitration effect.

[0012] Optionally, the bag dust collector includes a shell and an air inlet chamber, a filter chamber and an air outlet chamber which are arranged in the shell and connected in sequence, the filter chamber includes a filter unit for filtering smoke, and the air outlet chamber is located at the upper part of the shell; the bag dust collector also includes an air outlet channel, the top end of the air outlet channel is connected to the air outlet of the air outlet chamber, and the bottom end is connected to the flue.

[0013] Optionally, the front end of the flue is located in the shell of the bag filter and is connected to the air outlet of the air outlet cavity to form the air outlet channel.

[0014] Optionally, the longitudinal cross-section of the air inlet cavity is an L-shaped structure, the top of the L-shaped structure is connected to the exhaust port of the desulfurization reaction tower, and the air outlet cavity is located above the horizontal side of the L-shaped structure.

[0015] Optionally, there are two filter chambers, which are symmetrically arranged on both sides of the air inlet chamber and the air outlet chamber, and each filter chamber is provided with at least one row of filter units or a partition that divides the filter chamber into at least two rows of filter units; the air inlet sides of the filter units in the same row are connected in sequence, and the air outlet sides of the filter units in the same row are connected in sequence.

[0016] Optionally, it also includes a fan, which is arranged downstream of the air flow of the denitration reaction tower.

[0017] Optionally, an airflow distribution device is also provided in the flue.

[0018] Optionally, a heating device for heating the flue gas in the flue is also included.

[0019] In addition, the present invention also provides a circulating fluidized bed flue gas purification system, which includes a desulfurization reaction tower, a denitrification reaction tower and the integrated connection device as described above.

[0020] The technical effect of the circulating fluidized bed flue gas purification system having the integrated connection device as described above is similar to the technical effect of the integrated connection device described above, and will not be described here in order to save space. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a structural schematic diagram of a circulating fluidized bed flue gas purification system in the prior art;

[0022] Figure 2 It is a structural schematic diagram of a circulating fluidized bed flue gas purification system provided by an embodiment of the present invention;

[0023] Figure 3 yes Figure 2 Top view of the bag filter.

[0024] Attached Figure 1 In the figure, the reference numerals are described as follows:

[0025] 01-bag filter, 011-air outlet cavity; 02-flue, 021-horizontal section, 022-vertical section; 03-desulfurization reaction tower; 04-denitrification reaction tower;

[0026] Attached Figure 2-3 In the figure, the reference numerals are described as follows:

[0027] 1-bag filter, 11-air inlet chamber, 12-air outlet chamber, 13-filter chamber, 14-filter unit, 15-air outlet channel, 16-shell; 2-flue, 21-first vertical section, 22-first horizontal section, 23-second vertical section, 24-second horizontal section; 3-desulfurization reaction tower; 4-denitrification reaction tower. DETAILED DESCRIPTION

[0028] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0029] Please refer to Figure 2-3 , Figure 2 It is a structural schematic diagram of a circulating fluidized bed flue gas purification system provided by an embodiment of the present invention; Figure 3 yes Figure 2 Top view of the bag filter.

[0030] The embodiment of the present invention provides a circulating fluidized bed flue gas purification system and an integrated connection device thereof, such as Figure 2 As shown, the circulating fluidized bed flue gas purification system includes a desulfurization reaction tower 3, a denitration reaction tower 4 and the above-mentioned integrated connection device, wherein the integrated connection device includes a bag filter 1 and a flue 2, an air inlet is provided at the top of the bag filter 1, an air outlet is provided at the bottom of the bag filter 1, the exhaust port of the desulfurization reaction tower 3 is connected with the air inlet in the vertical direction, and the air outlet is connected with the denitration reaction tower 4 through the flue 2. Specifically, the front end of the flue 2 is connected with the air outlet of the bag filter 1 in the vertical direction.

[0031] Here, "front" refers to the side facing the upstream of the airflow, and "rear" refers to the side facing the downstream of the airflow.

[0032] The air inlet of the bag-type dust collector 1 is arranged at the top, and the air outlet is arranged at the bottom, instead of being led out from the side wall of the bag-type dust collector 1. Such arrangement enables the exhaust port of the desulfurization reaction tower 3 to be connected with the bag-type dust collector 1 through a vertically arranged flue gas pipeline, and the front end of the flue 2 can be directly led out from the air outlet in a vertical direction downward. In other words, the flue gas pipeline or flue 2 connected with the bag-type dust collector 1 is arranged in a vertical direction, and there is no need to set a bend at the air outlet of the flue 2.

[0033] like Figure 2 As shown, the flue 2 includes a first vertical section 21, a first horizontal section 22, a second vertical section 23 and a second horizontal section 24 which are connected in sequence, that is, two vertical sections and two horizontal sections, wherein the first vertical section 21 is connected to the air outlet of the bag filter 1, and the rear end of the second horizontal section 24 is connected to the denitration reaction tower 4. Figure 1 As shown, for the scheme in which the air outlet of the bag filter 1 is arranged on the side, a horizontal section arranged between the flue 2 and the denitrification reaction tower 4 can be reduced, thereby shortening the longitudinal arrangement distance of the device (from the desulfurization reaction tower 3 to the denitrification reaction tower 4), thereby reducing the overall occupied space of the circulating fluidized bed flue gas purification system, thereby improving the possibility of the overall arrangement of the circulating fluidized bed flue gas purification system within a limited site space.

[0034] Moreover, such an arrangement can reduce the number of bending sections so that the flue gas flow line is smooth and the flow field is uniform, which is conducive to the full contact between the denitration catalyst in the denitration reaction tower 4 and the flue gas, thereby improving the denitration effect.

[0035] In the above embodiment, the bag filter 1 includes a housing 16 and an air inlet chamber 11, a filter chamber 13 and an air outlet chamber 12 which are arranged in the housing 16 and are connected in sequence, wherein the filter chamber 13 includes a filter unit 14 for filtering the flue gas, and the air outlet chamber 12 is located at the upper part of the housing 16; that is, the bag filter 1 in this embodiment filters the flue gas through the filter unit 14, and the specific number of the filter units 14 can be set according to the exhaust volume and the flue gas emission requirements, so as to be suitable for different circulating fluidized bed flue gas purification systems, and has good applicability. The air outlet chamber 12 is arranged at the upper part of the housing 16, so that the flue gas filtered by the filter unit 14 can enter the air outlet chamber 12 upward.

[0036] At the same time, the bag filter 1 also includes an air outlet channel 15, the top of which is connected to the air outlet of the air outlet cavity 12, and the bottom of which is connected to the flue 2. Since the air outlet cavity 12 is arranged at the upper part of the shell 16, the air outlet channel 15 can lead the flue gas in the air outlet cavity 12 located above from the bottom end of the bag filter 1 and connect with the flue 2, so that the flue gas outlet is arranged in the longitudinal direction. In this way, compared with the prior art, the flue 2 in this embodiment is connected to the air outlet cavity 12 through the air outlet channel 15 provided in the bag dust collector 1, while the flue 2 in the prior art leads the smoke in the air outlet cavity 12 out from the side of the bag dust collector 1 by adding a bending section and a horizontal section. The solution provided in this embodiment can obviously reduce the space occupied by the flue 2. At the same time, since the air outlet channel 15 is located in the shell 16 or partially located in the shell 16, the smoke in the air outlet cavity 12 is discharged into the flue 2 along the air outlet channel 15, which can reduce the heat exchange between the smoke and the external environment, reduce heat loss, and have a good thermal insulation effect.

[0037] Furthermore, the front end of the flue 2 is located in the shell 16 and communicates with the air outlet of the air outlet cavity 12 to form the above-mentioned air outlet channel 15. In other words, the top end of the first vertical section 21 of the flue 2 is embedded in the bag filter 1 and communicates with the air outlet cavity 12 to form the above-mentioned air outlet channel 15, that is, the air outlet channel 15 becomes a part of the flue 2 and is embedded in the bag filter 1, forming an integrated structural design.

[0038] In the above embodiment, the longitudinal cross section of the air inlet cavity 11 is an L-shaped structure, the top of the L-shaped structure is connected to the exhaust port of the desulfurization reaction tower 3, and the air outlet cavity 12 is located above the horizontal side of the L-shaped structure. That is to say, in this embodiment, the air outlet cavity 12 is located above the air inlet cavity 11, and such an arrangement can make the structure inside the bag filter 1 more compact.

[0039] Alternatively, in this embodiment, the bag filter 1 further includes an air inlet passage, which passes through the air outlet cavity 12 and is connected between the air inlet cavity 11 located below and the desulfurization reaction tower 3, and can also realize the arrangement of the flue gas ducts in the longitudinal direction and the flue gas discharged from the desulfurization reaction tower 3 can be passed into the air inlet cavity 11. The air inlet cavity 11 is set as an L-shaped structure to simplify the connection operation between the air inlet cavity 11 and the flue gas pipeline.

[0040] In the above embodiment, each filter cavity 13 may be provided with a partition, which divides the filter cavity 13 into at least two rows of filter units 14, that is, the filter units 14 in each filter cavity 13 are arranged in at least two rows, and the air inlet sides of the filter units 14 arranged in the same row are connected in sequence, and the air outlet sides of the filter units 14 arranged in the same row are connected in sequence, so that the air inlet side of each filter unit 14 is connected to the air inlet cavity 11, and the air outlet side of each filter unit 14 is connected to the air outlet cavity 12, and the filter units 14 in two adjacent rows are isolated from each other.

[0041] Of course, in this embodiment, each filter cavity 13 may also be provided with only one row of filter units 14, and no specific limitation is made here. However, two filter cavities 13 are provided in the bag filter 1, and each filter cavity 13 includes at least two rows of filter units 14, or multiple filter units 14 may be provided to meet the situation of larger smoke emission and higher emission requirements, and the applicability is good.

[0042] In addition, the filter units 14 in the two filter chambers 13 are symmetrically arranged with respect to the air inlet chamber 11 and the air outlet chamber 12, that is, the air inlet chamber 11 and the air outlet chamber 12 are stacked in the middle position, and the filter chambers 13 are symmetrically arranged on both sides, so that the overall structure of the bag dust collector 1 can be more regular.

[0043] In the above embodiment, the circulating fluidized bed flue gas purification system also includes a fan (not shown in the figure), which is arranged downstream of the denitrification reaction tower 4 and can provide power for the flue gas circulation in the circulating fluidized bed flue gas purification system.

[0044] In the above embodiment, an airflow distribution device (not shown in the figure) is also provided in the flue 2, and a porous plate with multiple hole structures evenly arranged. Since the flue 2 includes two vertical sections and two horizontal sections, the connection between the vertical section and the horizontal section forms a corner, and a guide plate is provided at each corner, the airflow distribution device can play a role in stabilizing the flow of the flue gas entering the flue 2, so that the flue gas flow line in the flue 2 is smooth and the flow field is uniform everywhere. After entering the denitrification reactor, it can fully contact with the denitrification catalyst, thereby improving the denitrification effect.

[0045] In the above embodiment, the circulating fluidized bed flue gas purification system also includes a heating device for heating the flue gas in the flue 2. The heating device can be arranged inside the flue 2 or outside the flue 2 to increase the temperature of the flue gas before entering the denitrification reaction tower 4 to ensure the temperature requirement of the denitrification reaction tower 4 for the flue gas.

[0046] The above are only preferred embodiments of the present invention. It should be pointed out that, for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. An integrated connection device for a circulating fluidized bed flue gas purification system, characterized in that: It includes a bag filter (1) and a flue (2); The top of the bag filter (1) is provided with an air inlet, and the bottom of the bag filter (1) is provided with an air outlet, the air inlet is connected to the exhaust port of the desulfurization reaction tower (3) of the circulating fluidized bed flue gas purification system, and the air outlet is connected to the denitration reaction tower (4) of the circulating fluidized bed flue gas purification system through the flue (2); The front end of the flue (2) is connected to the air outlet in a vertical direction; The bag filter (1) comprises a housing (16), and an air inlet chamber (11), a filter chamber (13), and an air outlet chamber (12) which are arranged in the housing (16) and are sequentially connected to each other, the filter chamber (13) comprising a filter unit (14) for filtering smoke, and the air outlet chamber (12) is located at the upper part of the housing (16); The bag filter (1) further comprises an air outlet channel (15), the top end of the air outlet channel (15) being in communication with the air outlet of the air outlet cavity (12), and the bottom end of the air outlet channel (15) being in communication with the flue (2); The air outlet channel (15) is located inside the shell (16) or is partially located inside the shell (16); The longitudinal cross-section of the air inlet cavity (11) is an L-shaped structure, the top of the L-shaped structure is connected to the exhaust port of the desulfurization reaction tower (3), and the air outlet cavity (12) is located above the horizontal side of the L-shaped structure; The number of the filter chambers (13) is two, and the two filter chambers (13) are symmetrically arranged on both sides of the air inlet chamber (11) and the air outlet chamber (12). Each of the filter chambers (13) contains at least one row of filter units (14) or is provided with a partition plate that divides the filter chamber (13) into at least two rows of filter units (14); the air inlet sides of the filter units (14) arranged in the same row are connected in sequence, and the air outlet sides of the filter units (14) arranged in the same row are connected in sequence.

2. The integrated connection device according to claim 1, characterized in that: The front end of the flue (2) is located in the housing (16) of the bag filter (1) and is connected to the air outlet of the air outlet cavity (12) to form the air outlet channel (15).

3. The integrated connection device according to claim 1 or 2, characterized in that: It also includes a fan, which is arranged downstream of the airflow of the denitration reaction tower (4).

4. The integrated connection device according to claim 1 or 2, characterized in that: An airflow distribution device is also provided in the flue (2).

5. The integrated connection device according to claim 1 or 2, characterized in that: It also includes a heating device for heating the flue gas in the flue (2).

6. A circulating fluidized bed flue gas purification system, characterized in that: It comprises a desulfurization reaction tower (3), a denitration reaction tower (4) and an integrated connection device as claimed in any one of claims 1 to 5.

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