Flue gas dehydrochlorination device

Abstract

The utility model discloses a flue gas dehydrochlorination device which comprises a tank body, a gas inlet and a gas outlet, a baffling multi-channel comprising two channels is arranged on the side edge of the tank body, each channel of the baffling multi-channel is communicated with the gas inlet, a first inlet baffle and an inlet flue gas rectification grid are sequentially arranged in a first channel of the baffling multi-channel, and a second inlet baffle is arranged in a second channel of the baffling multi-channel. A second inlet baffle is arranged in a second channel of the multiple baffling channels, a fixed bed dechlorination system is further arranged in the tank body, a first rectification grid and a plurality of denitration catalyst layers are further arranged in the tank body, the fixed bed dechlorination system comprises a plurality of layers of partition plates, a dechlorination agent layer is arranged above each layer of partition plate, and a second inlet baffle is arranged above each layer of partition plate. All the partition plates are matched to separate the space above the tank body into an S-shaped channel, one end of the S-shaped channel is communicated with the second channel, the other end of the S-shaped channel is communicated with the lower portion of the tank body, and an electric baffle door is arranged at the position where the S-shaped channel is communicated with the lower portion of the tank body. According to the structure, the content of hydrogen chloride entering the low-temperature denitration system is greatly reduced.

Description

Technical Field

[0001] The utility model belongs to the technical field related to low-temperature denitrification of waste flue gas, and particularly relates to a device for removing hydrogen chloride from flue gas. Background Technique

[0002] At present, the hydrogen chloride content in waste flue gas is mostly 900 - 1500 mg / Nm3, and a semi-dry dechlorination system is arranged at the front end of the low-temperature denitrification system. However, due to the frequent fluctuation of the hydrogen chloride value in the waste flue gas and the problem of the regulation lag of the semi-dry dechlorination system, it often causes the hydrogen chloride content in the subsequent flue gas low-temperature denitrification treatment process to exceed the standard, seriously affecting the chemical service life of the low-temperature catalyst.

[0003] At present, the low-temperature denitrification system of waste incineration only relies on the front-end semi-dry dechlorination system to ensure the hydrogen chloride concentration in the flue gas. In order to reduce the hydrogen chloride concentration in the flue gas to a reasonable range, a large amount of alkaline substances need to be added and the flue gas reaction temperature needs to be reduced. However, the large input of alkaline substances and the significant reduction of the flue gas temperature will lead to an increase in the burden of bag dust removal and an increase in the steam consumption of the subsequent low-temperature denitrification system due to the low flue gas temperature. Moreover, the conventional waste incineration furnace flue gas denitrification system is only a low-temperature denitrification reaction system, and the denitrification system does not contain a dry dechlorination device, which causes the phenomenon of hydrogen chloride poisoning of the low-temperature catalyst. Therefore, improvement is needed. Summary of the Utility Model

[0004] The purpose of the utility model is to provide a device for removing hydrogen chloride from flue gas, which solves the problems that the existing waste incineration furnace flue gas denitrification system is prone to increase the burden of bag dust removal and cause the phenomenon of hydrogen chloride poisoning of the low-temperature catalyst.

[0005] To solve the above technical problems, the utility model is realized through the following technical solutions:

[0006] The utility model relates to a hydrogen chloride removal device for flue gas, which comprises a tank body. An air inlet is arranged on the side of the upper part of the tank body, and an air outlet is arranged at the bottom of the tank body. A baffle multi-channel with two channels is arranged in the tank body, and each channel on the baffle multi-channel is communicated with the air inlet. An inlet baffle one and an inlet flue gas rectifying grid are sequentially arranged in the first channel of the baffle multi-channel. An inlet baffle two is arranged in the second channel of the baffle multi-channel. A fixed-bed dechlorination system located above the second channel is also arranged in the tank body. A rectifying grid one and multiple layers of denitration catalyst layers are sequentially arranged at intervals from top to bottom in the tank body. The fixed-bed dechlorination system comprises multiple layers of partition plates arranged at intervals. A dechlorination agent layer is arranged above each layer of partition plate, and all the partition plates cooperate to isolate the space above the tank body into an S-shaped channel. One end of the S-shaped channel is communicated with the second channel, and the other end of the S-shaped channel is communicated with the lower part of the tank body. An electric baffle door is arranged at the position where the S-shaped channel is communicated with the lower part of the tank body.

[0007] Preferably, there are three layers of partition plates, namely a first partition plate, a second partition plate and a third partition plate. A baffle multi-channel in a zigzag shape is communicated with the left side above the tank body, and the air inlet is arranged above the left side of the baffle multi-channel. The left sides of the first partition plate and the third partition plate are connected with the inner wall of the baffle multi-channel. There is a gas communication port one for gas passage between the right sides of the first partition plate and the third partition plate and the right side of the tank body. The right side of the second partition plate is connected with the inner wall of the right side of the tank body, and there is a gas communication port two for gas passage between the left side of the second partition plate and the inner wall of the baffle multi-channel. The electric baffle door is arranged in the gas communication port one on the side of the third partition plate.

[0008] Preferably, to avoid incomplete filtration, the dechlorination agent layer on the second partition plate abuts against the bottom of the first partition plate, and the dechlorination agent layer on the third partition plate abuts against the bottom of the second partition plate.

[0009] Preferably, to achieve automatic control, a first electric control valve for controlling the opening or closing of the inlet baffle one is arranged outside the baffle multi-channel, a second electric control valve for controlling the opening or closing of the inlet baffle two is arranged inside the baffle multi-channel, and a third electric control valve for controlling the opening or closing of the electric baffle door is arranged on the side of the tank body.

[0010] Preferably, the dechlorination agent layer adopts a structure with a mesh box body on the outside and dechlorination agent filled inside.

[0011] Preferably, there are two layers of denitration catalyst layers, which are arranged at intervals.

[0012] Preferably, a funnel part is arranged at the bottom of the tank body, and the air outlet is arranged at the lower opening of the funnel part.

[0013] Preferably, the mesh box body includes a box body and a grid drawer box slidably arranged in the box body, and the dechlorination agent is placed in the grid drawer box.

[0014] The utility model has the following beneficial effects: This structure mainly solves the problem that in the field of low-temperature denitrification of waste flue gas, the removal efficiency of hydrogen chloride at the front end is unstable, resulting in the phenomenon of hydrogen chloride poisoning of the low-temperature catalyst. The utility model adopts an integrated design of a dry hydrogen chloride removal reactor and a low-temperature denitrification reactor. A separate dry hydrogen chloride removal reactor is designed above the low-temperature denitrification reactor, thereby greatly reducing the hydrogen chloride concentration in the flue gas and avoiding the phenomenon of hydrogen chloride poisoning of the catalyst. A fixed-bed dechlorination system is arranged above the low-temperature denitrification reactor, and a multi-channel dry dechlorination method is adopted to extend the contact time between hydrogen chloride and the dechlorination agent. At the same time, a bypass design method is formed by a baffle multi-channel. After the dechlorination agent is saturated, the bypass can be switched, and the dechlorination agent can be taken out and updated, which greatly reduces the content of hydrogen chloride entering the low-temperature denitrification system and effectively extends the service life of the low-temperature catalyst. Moreover, the S-shaped channel adopted by this device makes the flow field stable, the flue gas shunting uniform, and the flue gas dechlorination effect remarkable. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic internal structure diagram of a flue gas hydrogen chloride removal device in Embodiment 1;

[0016] Figure 2 It is a schematic structural diagram of the mesh box body in Embodiment 1;

[0017] Figure 3 It is a schematic pull-out structure diagram of the mesh box body in Embodiment 2.

[0018] REFERENCE SIGNS:

[0019] 1 - inlet baffle one, 2 - dechlorination agent layer, 3 - first partition board, 4 - electric baffle door, 5 - inlet baffle door, 6 - rectifying grille, 7 - denitrification catalyst layer, 8 - second partition board, 9 - third partition board, 10 - inlet flue gas rectifying grille, 11 - tank body, 12 - air inlet, 13 - air outlet, 14 - baffle multi-channel, 141 - first channel, 142 - second channel, 15 - S-shaped channel, 16 - gas communication port one, 17 - gas communication port two, 18 - first electric control valve, 19 - second electric control valve; 20 - third electric control valve; 201 - mesh box body, 21 - funnel part, 2011 - box body, 2012 - grid drawer box. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0020] To make the objectives, technical solutions and advantages of the embodiments of the present utility model clearer, the technical solutions in the embodiments of the present utility model will be clearly and completely described below in conjunction with the embodiments of the present utility model. Apparently, the described embodiments are part of the embodiments of the present utility model, rather than all of them. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present utility model without creative efforts belong to the scope of protection of the present utility model.

[0021] Embodiment 1

[0022] Please refer to Figure 1-2 As shown, it should be noted that Figure 1 the English letters around the arrow in are GAS indicating gas, and the arrow indicates the flow direction of the gas on the surface. A hydrogen chloride removal device for flue gas disclosed in this embodiment includes a tank body 11, an air inlet 12 is provided on the side above the tank body 11, an air outlet 13 is provided at the bottom of the tank body 11, a baffle multi-channel 14 including two channels is provided in the tank body 11, and each channel on the baffle multi-channel 14 is communicated with the air inlet 12. An inlet baffle 1 and an inlet flue gas rectifying grid 10 are sequentially arranged in the first channel 141 of the baffle multi-channel 14. An inlet baffle 5 is provided in the second channel 142 of the baffle multi-channel 14. A fixed bed dechlorination system is also provided in the tank body 11 above the second channel 142. A rectifying grid 6 and multiple layers of denitration catalyst layers 7 are sequentially arranged at intervals from top to bottom in the tank body 11. The fixed bed dechlorination system includes multiple layers of partition plates arranged at intervals, and a dechlorination agent layer 2 is provided above each layer of partition plate. All the partition plates cooperate to isolate the space above the tank body 11 into an S-shaped channel 15. One end of the S-shaped channel 15 is communicated with the second channel 142, and the other end of the S-shaped channel 15 is communicated with the lower part of the tank body 11. An electric baffle door 4 is provided at the position where the S-shaped channel 15 is communicated with the lower part of the tank body 11.

[0023] Preferably, there are three layers of the partition plates, namely a first partition plate 3, a second partition plate 8 and a third partition plate 9. A baffle multi-channel 14 in a zigzag shape is communicated on the left side above the tank body 11, and the air inlet 12 is provided above the left side of the baffle multi-channel 14. The left sides of the first partition plate 3 and the third partition plate 9 are connected to the inner wall of the baffle multi-channel 14. There is a gas communication port 16 for gas passage between the right sides of the first partition plate 3 and the third partition plate 9 and the right side of the tank body 11. The right side of the second partition plate 8 is connected to the inner wall of the right side of the tank body 11, and there is a gas communication port 17 for gas passage between the left side of the second partition plate 8 and the inner wall of the baffle multi-channel 14. The electric baffle door 4 is located in the gas communication port 16 on the side of the third partition plate 9.

[0024] Preferably, to avoid incomplete filtration, the dechlorination agent layer 2 on the second partition plate 8 abuts against the bottom of the first partition plate 3, and the dechlorination agent layer 2 on the third partition plate 9 abuts against the bottom of the second partition plate 8.

[0025] Preferably, to achieve automatic control, a first electric control valve 18 for controlling the opening or closing of the inlet baffle 1 is provided outside the baffle multi-channel 14, a second electric control valve 19 for controlling the opening or closing of the inlet baffle 2 5 is provided inside the baffle multi-channel 14, and a third electric control valve 20 for controlling the opening or closing of the electric baffle door 4 is provided on the side of the tank body 11.

[0026] Preferably, the dechlorination agent layer 2 has a structure with a mesh box body 201 on the outside and dechlorination agent filled inside.

[0027] Preferably, there are two layers of the denitration catalyst layer 7, which are arranged at intervals.

[0028] Preferably, a funnel part 21 is provided at the bottom of the tank body 11, and the air outlet 13 is located at the lower opening of the funnel part 21.

[0029] The structure adds a unique baffle multi-channel 14, allowing the flue gas containing hydrogen chloride gas to enter the baffle multi-channel 14 from the air inlet 12, and then enter the fixed bed dechlorination system inside the tank body 11, i.e., dry dechlorination, after passing through the inlet baffle 1 and the inlet flue gas rectifying grid 10. After reacting with the dechlorinating agent layer 2 (the denitration catalyst layer adopts the added dechlorinating agent in the mesh box body 201 structure) placed above the first layer of partition 3, the flue gas containing unabsorbed hydrogen chloride flows from the right gas channel to the second layer of partition 8, and reacts with the dechlorinating agent layer 2 placed above the second layer of partition 8; the flue gas containing unabsorbed hydrogen chloride flows into the second layer of partition 8 from the right gas channel, and reacts with the dechlorinating agent layer 2 placed above the second layer of partition 8; The flue gas of absorbed hydrogen chloride flows from the left gas channel to the top of the third partition plate 9, and reacts with the dechlorinating agent layer 2 placed above the third partition plate 9, and passes through each layer in turn along the return path in the partition, that is, the S-shaped channel 15, and the hydrogen chloride gas is gradually absorbed by the dechlorinating agent of each layer. When it reaches the bottom, the hydrogen chloride has been basically absorbed and removed. Then, the flue gas after passing through the dry dechlorination system passes through the electric baffle door 4 and the sorting grid 6 and enters the low-temperature denitration reactor (composed of a rectifying grid 6 and a multi-layer denitration catalyst layer 7) at the bottom to carry out the denitration reaction; when the dechlorinating agent is saturated, it can be By closing the inlet damper 1, opening the inlet damper door 5, and closing the electric damper door 4, the dry dechlorination system can be isolated, and then the dechlorinating agent can be replaced. Therefore, this structure mainly solves the problem that the front-end hydrogen chloride removal efficiency is unstable in the garbage flue gas low-temperature denitration industry, which leads to the low-temperature catalyst hydrogen chloride poisoning phenomenon. The utility model adopts an integrated design of a dry dehydrochlorination reactor and a low-temperature denitration reactor, and designs a separate dry dehydrochlorination reactor on the upper part of the low-temperature denitration reactor, thereby greatly reducing the hydrogen chloride concentration in the flue gas and avoiding the catalyst from being poisoned by hydrogen chloride. A fixed bed dechlorination system is arranged on the upper part of the device, and a multi-channel dry dechlorination method is adopted to prolong the contact time between hydrogen chloride and the dechlorinating agent; at the same time, the baffled multi-channel 14 constitutes a bypass design method. After the dechlorinating agent is saturated, the bypass switching can be performed, and the dechlorinating agent can be taken out and updated, which greatly reduces the content of hydrogen chloride entering the low-temperature denitration system and effectively prolongs the service life of the low-temperature catalyst. In addition, the device adopts an S-shaped channel 15 to stabilize the flow field, evenly divert the flue gas, and achieve a significant flue gas dechlorination effect. It should be noted that the denitration catalyst layer 7 belongs to the conventional technology in this field, so it is not described in detail.

[0030] Example 2

[0031] See also Figure 3As shown, the overall structure of a hydrogen chloride removal device disclosed in this embodiment is the same as that in Embodiment 1. The difference is that, preferably, the mesh box body 201 includes a box body 2011 and a mesh drawer box 2012 which is arranged in a drawer type in the box body 2011. The dechlorination agent is placed in the mesh drawer box 2012. In this embodiment, the mesh box body 201 adopts a drawer type structure, which is convenient for replacing the dechlorination agent inside in the later stage. Moreover, for the convenience of viewing, Figure 3 in order to show the shapes of the mesh holes of the box body 2011 and the mesh drawer box 2012, how to form the mesh holes of the box body 2011 and the mesh drawer box 2012 belongs to the conventional technology in the art, so no specific description will be made here.

[0032] The above are only the preferred embodiments of the present invention, which do not limit the present invention. Any modification to the technical solutions recorded in the foregoing embodiments, any equivalent replacement of some technical features, and any modification, equivalent replacement, and improvement made are all within the protection scope of the present invention.

Claims

1. A hydrogen chloride removal device for flue gas, comprising a tank body (11), an air inlet (12) is arranged on the side above the tank body (11), and an air outlet (13) is arranged at the bottom of the tank body (11), and it is characterized in that: Inside the tank body (11), a baffle multi-channel (14) including two channels is provided, and each channel on the baffle multi-channel (14) is communicated with the air inlet (12). An inlet baffle one (1) and an inlet flue gas rectifying grille (10) are sequentially arranged in the first channel (141) of the baffle multi-channel (14). An inlet baffle two (5) is arranged in the second channel (142) of the baffle multi-channel (14). A fixed bed dechlorination system is also arranged in the tank body (11) above the second channel (142). A rectifying grille one (6) and multiple layers of denitration catalyst layers (7) are sequentially arranged at intervals from top to bottom in the tank body (11). The fixed bed dechlorination system includes multiple layers of partition plates arranged at intervals. A dechlorination agent layer (2) is arranged above each layer of partition plate, and all the partition plates cooperate to isolate the space above the tank body (11) into an S-shaped channel (15). One end of the S-shaped channel (15) is communicated with the second channel (142), and the other end of the S-shaped channel (15) is communicated with the lower part of the tank body (11). An electric baffle door (4) is arranged at the position where the S-shaped channel (15) is communicated with the lower part of the tank body (11).

2. The hydrochloric acid removal device for flue gas according to claim 1, characterized in that: There are three layers of the partition plates, namely a first partition plate (3), a second partition plate (8) and a third partition plate (9). A baffle multi-channel (14) in a zigzag shape is communicated with the upper left side of the tank body (11), and the air inlet (12) is arranged above the left side of the baffle multi-channel (14). The left sides of the first partition plate (3) and the third partition plate (9) are connected to the inner wall of the baffle multi-channel (14). There is a gas communication port one (16) for gas passage between the right sides of the first partition plate (3) and the third partition plate (9) and the right side of the tank body (11). The right side of the second partition plate (8) is connected to the inner wall of the right side of the tank body (11), and there is a gas communication port two (17) for gas passage between the left side of the second partition plate (8) and the inner wall of the baffle multi-channel (14). The electric baffle door (4) is located in the gas communication port one (16) on the side of the third partition plate (9).

3. The flue gas hydrogen chloride removal device according to claim 2, characterized in that: The dechlorination agent layer (2) on the second partition plate (8) abuts against the bottom of the first partition plate (3), and the dechlorination agent layer (2) on the third partition plate (9) abuts against the bottom of the second partition plate (8).

4. The flue gas hydrogen chloride removal device according to claim 2, characterized in that: A first electric control valve (18) for controlling the opening or closing of the inlet baffle one (1) is arranged outside the baffle multi-channel (14). A second electric control valve (19) for controlling the opening or closing of the inlet baffle two (5) is arranged inside the baffle multi-channel (14). A third electric control valve (20) for controlling the opening or closing of the electric baffle door (4) is arranged on the side of the tank body (11).

5. The fume dehydrochlorination device according to claim 1, wherein: The dechlorination agent layer (2) adopts a structure with a mesh box body (201) on the outside and dechlorination agent filled inside.

6. The hydrochloric acid removal device for flue gas according to claim 1, characterized in that: There are two layers of the denitration catalyst layers (7), and they are arranged at intervals.

7. The hydrochloric acid removal device for flue gas according to claim 1, wherein: A funnel part (21) is arranged at the bottom of the tank body (11), and the air outlet (13) is arranged at the lower opening of the funnel part (21).

8. A hydrogen chloride removal device for flue gas according to claim 5, characterized in that: The described mesh box body (201) includes a box body (2011) and a grid drawer box (2012) which is arranged in the box body (2011) in a pull-out manner, and the dechlorination agent is placed in the grid drawer box (2012).

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