Flue gas waste heat recovery boiler for removing Fe-containing dust

Abstract

The utility model discloses a flue gas waste heat recovery boiler for removing Fe-containing dust, belongs to the technical field of ironmaking boilers, and mainly solves the technical problems that in the prior art, a waste heat recovery boiler can generate flue gas containing iron-containing dust in the steelmaking process, the iron-containing dust is large in density and prone to being deposited on the surface of a heat exchange device of the boiler, and the iron-containing dust is prone to falling off. A dust removal barrel is arranged, a waste heat boiler body is arranged on one side of the dust removal barrel, a centrifugal exhaust fan is installed on the side, away from the waste heat boiler body, of the dust removal barrel, a heat exchange tube nest is installed in the waste heat boiler body, and the output end of the centrifugal exhaust fan is connected with a smoke inlet pipe; an outer rotational flow and an inner rotational flow are arranged in the dust removal barrel, a flow guide pipe is embedded in the top of the dust removal barrel, the end, away from the waste heat furnace body, of the flow guide pipe is fixedly connected with an air inlet cover, an ash removal plate is arranged in the waste heat furnace body in a lifting mode, and a plurality of silicon nitride ceramic scrapers are fixedly connected to the inner wall of the ash removal plate.

Description

Technical Field

[0001] The utility model relates to the technical field of iron-making boilers, and more specifically, to a flue gas waste heat recovery boiler for removing Fe-containing dust. Background Art

[0002] Generally speaking, electric furnaces, blast furnaces, converters and other steel production equipment will generate a large amount of high-temperature and high-dust flue gas during the steelmaking and ironmaking processes. The flue gas temperature is 1500℃~1600℃, and the highest flue gas temperature reaches above 2000℃. The flue gas generated contains a large amount of iron dust, high density, and high heat. A waste heat recovery boiler is needed to recover the heat contained in the flue gas.

[0003] However, there are various types of waste heat recovery boilers in the prior art. For example, utility model patent CN212692551U relates to a deep waste heat recovery boiler for a steelmaking converter. The utility model fixes an anti-wear component inside the high-heat access pipe to prevent the high-temperature furnace gas from causing wear on the bent part of the high-heat access pipe. Two support rods are installed inside the recovery furnace body, and a high-temperature resistant inner liner is placed on top of the two support rods. The two support rods support the high-temperature resistant inner liner, so that the high-temperature resistant inner liner is not easily expanded and damaged after a thermal stress reaction occurs when heated.

[0004] The waste heat recovery boiler has good anti-wear and explosion-proof effects, which increases the stability of equipment operation. However, the boiler will produce flue gas containing iron dust during the steelmaking process. The iron dust has a large density and is easily deposited on the surface of the boiler's heat exchange device, thereby affecting the boiler's heat exchange efficiency. In order to avoid this phenomenon, it is necessary to design a flue gas waste heat recovery boiler that removes Fe dust. Utility Model Content

[0005] The purpose of this section is to summarize some aspects of the embodiments of the utility model and briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this section and the specification abstract and utility model name of this application to avoid blurring the purpose of this section, specification abstract and utility model name, and such simplifications or omissions cannot be used to limit the scope of the utility model.

[0006] In order to achieve the above object, the utility model provides a flue gas waste heat recovery boiler for removing Fe-containing dust, which is achieved by the following specific technical means:

[0007] A flue gas waste heat recovery boiler for removing Fe-containing dust comprises a dust removal cylinder, a waste heat furnace body is arranged on one side of the dust removal cylinder, a centrifugal exhaust fan is installed on the side of the dust removal cylinder away from the waste heat furnace body, a heat exchange tube array is installed inside the waste heat furnace body, an output end of the centrifugal exhaust fan is connected to a smoke inlet pipe, an outer vortex and an inner vortex are arranged inside the dust removal cylinder, a guide pipe is embedded in the top of the dust removal cylinder, an end of the guide pipe away from the waste heat furnace body is fixedly connected to an air intake hood, a cleaning plate is arranged for lifting inside the waste heat furnace body, and a plurality of silicon nitride ceramic scrapers are fixedly connected to the inner wall of the cleaning plate.

[0008] Preferably, one end of the smoke inlet pipe extends into the dust removal cylinder, one end of the guide pipe extends into the waste heat furnace body, the heat exchange tubes are curved, two fixed support rods are provided on the outer surface of the heat exchange tubes, and one end of the fixed support rods is fixedly connected to the inner wall of the waste heat furnace body.

[0009] Preferably, the iron-containing dust fume conveyed by the centrifugal exhaust fan forms an outer vortex flow rotating downward in the upper cylinder of the dust removal cylinder, while the purified fume from which the iron-containing dust is removed forms an inner vortex flow spirally ascending in the lower cone of the dust removal cylinder.

[0010] Preferably, the inner wall of the waste heat furnace body is fixedly connected to a support plate, the top of the support plate is rotatably connected to a screw via a bearing, and the screw is located in the waste heat furnace body, the surface of the screw is threadedly connected to a movable seat, and one side surface of the movable seat is fixedly connected to one end of the cleaning plate, the upper surface of the support plate is fixedly connected to a guide rod, and the guide rod is fixed to one side of the screw.

[0011] Preferably, a fixing frame is fixedly connected to the top of the waste heat furnace body, and the fixing frame is U-shaped, and a servo motor is fixedly installed on the top of the fixing frame.

[0012] Preferably, the cleaning plate moves on the surface of the heat exchange tubes, and the silicon nitride ceramic scraper is made of silicon nitride ceramic material and has good high temperature resistance.

[0013] Preferably, a dust collecting pipe is fixedly connected to the bottom end of the dust removal cylinder, a fixed sleeve is threadedly fixed to the outer surface of the dust collecting pipe, a dust filter bag is fixedly connected to one end of the fixed sleeve, and an ash discharge port is embedded in the bottom of the waste heat furnace body, which is used to collect dust accumulated on the surface of the heat exchange tubes.

[0014] Preferably, a plurality of supporting legs are fixedly connected to the outer surface of the dust removal cylinder, the input end of the centrifugal exhaust fan is connected to a dust-containing smoke pipe, a water inlet is provided at one end of the heat exchange tube, a water outlet is provided at the other end of the heat exchange tube, and both ends of the heat exchange tube extend outside the waste heat furnace body.

[0015] Due to the application of the above technical solution, the utility model has the following advantages compared with the prior art:

[0016] After passing through the conveying function of the centrifugal exhaust fan, the flue gas containing iron dust is transported from the smoke inlet pipe to the dust removal cylinder. Then, the cyclone dust removal technology is used to make the flue gas containing iron dust form a rotating downward outer vortex in the upper cylinder of the dust removal cylinder. Under the action of centrifugal force, the dust suspended in the outer vortex slowly accumulates downward on the inner wall of the lower cone of the dust removal cylinder and flows along the dust removal cylinder. The purified flue gas that removes the iron dust will form a spiral upward inner vortex, and the rising flue gas is guided into the waste heat furnace by a guide pipe to remove the iron dust in the flue gas. Prevent dust from entering the furnace with the flue gas and forming dust accumulation on the surface of the heat exchange structure for waste heat recovery, thereby avoiding affecting the heat exchange efficiency of the waste heat furnace body. The residual iron-containing dust that cannot be completely removed is prone to deposition during the waste heat recovery process and forms dust accumulation on the surface of the heat exchange tubes. The lifting cleaning plate drives the silicon nitride ceramic scraper to move up and down, and uses the silicon nitride ceramic scraper to scrape off the dust, so that the dust falls down, removes the iron-containing dust deposited on the surface of the heat exchange tubes, cleans the heat exchange surface, and further ensures the heat exchange efficiency of the heat exchange tubes. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The drawings constituting a part of this application are used to provide a further understanding of the present invention. The illustrative embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation on the present invention. In the drawings:

[0018] Figure 1 It is a schematic diagram of the overall structure of the utility model;

[0019] Figure 2 It is a front cross-sectional schematic diagram of the utility model;

[0020] Figure 3 It is a perspective structural diagram of the dust removal cylinder;

[0021] Figure 4 It is a schematic front cross-sectional view of the waste heat furnace body;

[0022] Figure 5 It is a structural schematic diagram of heat exchange tubes;

[0023] Figure 6 It is a partial structural schematic diagram of the utility model.

[0024] In the figure: 1. dust removal cylinder; 2. waste heat furnace body; 3. centrifugal exhaust fan; 4. smoke inlet pipe; 5. external vortex; 6. internal vortex; 7. guide pipe; 8. air intake hood; 9. heat exchange tubes; 10. cleaning plate; 11. silicon nitride ceramic scraper; 12. fixed support rod; 13. support plate; 14. screw; 15. movable seat; 16. fixed frame; 17. servo motor; 18. guide rod; 19. dust collecting pipe; 20. fixed sleeve; 21. dust filter bag; 22. ash discharge port; 23. support leg; 24. dust-containing smoke pipe; 25. water inlet; 26. water outlet. DETAILED DESCRIPTION

[0025] In order to make the above-mentioned purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the accompanying drawings.

[0026] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0027] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure or characteristic that may be included in at least one implementation of the present invention. The term "in one embodiment" that appears in different places in this specification does not refer to the same embodiment, nor is it a separate or selective embodiment that is mutually exclusive with other embodiments. The present invention provides the following embodiments.

[0028] like Figure 1 , Figure 2 as well as Figure 3As shown, it is a structural schematic diagram of the flue gas waste heat recovery boiler for removing Fe dust in this embodiment. The flue gas waste heat recovery boiler for removing Fe dust in this embodiment is used to recover and reuse the waste heat contained in the flue gas generated by the iron-making boiler, and remove the iron-containing dust in the flue gas, so as to facilitate the subsequent secondary processing of the iron-containing dust. The flue gas waste heat recovery boiler comprises a dust removal cylinder 1 and a waste heat furnace body 2. The waste heat furnace body 2 is arranged on one side of the dust removal cylinder 1. A centrifugal exhaust fan 3 is installed on the side of the dust removal cylinder 1 away from the waste heat furnace body 2. The output end of the centrifugal exhaust fan 3 is connected to a smoke inlet pipe 4, and one end of the smoke inlet pipe 4 extends into the dust removal cylinder 1. An outer vortex 5 and an inner vortex 6 are arranged inside the dust removal cylinder 1. A guide pipe 7 is embedded in the top of the dust removal cylinder 1, and one end of the guide pipe 7 extends into the waste heat furnace body 2. The guide pipe 7 is away from the waste heat furnace body 2. One end is fixedly connected with an air intake hood 8. The iron-making boiler equipment transports the flue gas containing iron dust from the flue dust inlet pipe 4 to the dust removal cylinder 1 through the centrifugal exhaust fan 3. Then, the cyclone dust removal technology is used to form a rotating downward outer vortex 5 in the upper cylinder of the dust removal cylinder 1. Under the action of centrifugal force, the dust suspended in the outer vortex 5 slowly accumulates downward on the inner wall of the lower cone of the dust removal cylinder 1, so that the iron-containing dust flows along the inner wall of the dust removal cylinder 1, and the purified flue gas with iron dust removed will form a spiral upward inner vortex 6, and through the guiding effect of the guide pipe 7 and the air intake hood 8, the rising flue gas is introduced into the waste heat furnace body 2, thereby removing the iron-containing dust in the flue gas, preventing the iron-containing dust with high density and easy deposition from entering the waste heat furnace body 2 with the flue gas, and forming dust accumulation on the surface of the heat exchange structure for waste heat recovery, thereby avoiding affecting the heat exchange efficiency of the waste heat furnace body 2.

[0029] In addition, if Figure 6 As shown, in this embodiment, the interior of the waste heat furnace body 2 is equipped with heat exchange tubes 9, and the heat exchange tubes 9 are curved. A cleaning plate 10 is provided inside the waste heat furnace body 2 for lifting, and the cleaning plate 10 is movable on the surface of the heat exchange tubes 9. A plurality of silicon nitride ceramic scrapers 11 are fixedly connected to the inner wall of the cleaning plate 10. The silicon nitride ceramic scraper 11 is made of silicon nitride ceramic material and has good high temperature resistance. The silicon nitride ceramic scraper 11 fits the heat exchange tubes 9. Although the iron-containing dust in the flue gas is removed by the dust removal cylinder 1, However, it cannot be completely removed, and the residual iron-containing dust is easy to deposit in the waste heat recovery process, thereby forming dust accumulation on the surface of the heat exchange tubes 9. When iron-containing dust is accumulated, the lifting cleaning plate 10 drives multiple silicon nitride ceramic scrapers 11 to move up and down, and the silicon nitride ceramic scrapers 11 are used to scrape the iron-containing dust on the surface of the heat exchange tubes 9, so that the dust falls down, and the iron-containing dust deposited on the surface of the heat exchange tubes 9 is removed, the heat exchange surface is cleaned, and the heat exchange efficiency of the heat exchange tubes 9 in the waste heat furnace body 2 is further ensured.

[0030] It is worth noting that in this embodiment, two fixed support rods 12 are provided on the outer surface of the heat exchange tubes 9 , and one end of the fixed support rod 12 is fixedly connected to the inner wall of the waste heat furnace body 2 .

[0031] like Figure 4 As shown, in the present embodiment, in order to better enable the cleaning plate 10 to move up and down in the waste heat furnace body 2, a support plate 13 is fixedly connected to the inner wall of the waste heat furnace body 2, and a screw 14 is rotatably connected to the top of the support plate 13 through a bearing, and the screw 14 is located in the waste heat furnace body 2, and a movable seat 15 is threadedly connected to the surface of the screw 14, and one side surface of the movable seat 15 is fixedly connected to one end of the cleaning plate 10, and a guide rod 18 is fixedly connected to the upper surface of the support plate 13, and the guide rod 18 is fixed to one side of the screw 14, and the rotating screw 14 drives the movable seat 15 on its surface to move together, and the guiding effect of the guide rod 18 allows the cleaning plate 10 to rise and fall together with the movable seat 15.

[0032] It is worth noting that in this embodiment, a fixing frame 16 is fixedly connected to the top of the waste heat furnace body 2, and the fixing frame 16 is U-shaped. A servo motor 17 is installed on the top of the fixing frame 16, and the installed servo motor 17 provides driving force for the rotation of the screw 14.

[0033] like Figure 2 and Figure 3 As shown, in this embodiment, the bottom end of the dust removal cylinder 1 is fixedly connected to a dust collecting pipe 19, and a fixing sleeve 20 is threadedly fixed to the outer surface of the dust collecting pipe 19. One end of the fixing sleeve 20 is fixedly connected to a dust filter bag 21, and the dust filter bag 21 is located below the dust filter bag 21. The density of iron-containing dust is large. Under the action of its own gravity and the internal vortex 6, it slides into the dust collecting pipe 19 along the inner wall of the lower cone of the dust removal cylinder 1, enters the dust filter bag 21 from the dust collecting pipe 19, and collects the removed iron-containing dust. An ash discharge port 22 is embedded in the bottom of the waste heat furnace body 2, and the ash discharge port 22 is used to collect dust accumulated on the surface of the heat exchange tubes 9.

[0034] like Figure 2 As shown, in this embodiment, the outer surface of the dust removal cylinder 1 is fixedly connected with a plurality of supporting legs 23, and the input end of the centrifugal exhaust fan 3 is connected with a dusty smoke pipe 24, which is used to discharge the iron-containing dusty smoke generated by the iron-making boiler to facilitate the waste heat recovery operation of the smoke.

[0035] like Figure 5 As shown, in this embodiment, a water inlet 25 is provided at one end of the heat exchange tube 9 , a water outlet 26 is provided at the other end of the heat exchange tube 9 , and both ends of the heat exchange tube 9 extend to the outside of the waste heat furnace body 2 .

[0036] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A flue gas waste heat recovery boiler for removing Fe-containing dust, comprising a dust removal cylinder (1), a waste heat furnace body (2) being arranged on one side of the dust removal cylinder (1), a centrifugal exhaust fan (3) being installed on the side of the dust removal cylinder (1) away from the waste heat furnace body (2), and a heat exchange tube (9) being installed inside the waste heat furnace body (2), characterized in that: The output end of the centrifugal exhaust fan (3) is connected to a smoke inlet pipe (4); an external vortex (5) and an internal vortex (6) are arranged inside the dust removal cylinder (1); a guide pipe (7) is embedded in the top of the dust removal cylinder (1); an end of the guide pipe (7) away from the waste heat furnace body (2) is fixedly connected to an air intake hood (8); a ash cleaning plate (10) is arranged inside the waste heat furnace body (2) in a lifting manner; and a plurality of silicon nitride ceramic scrapers (11) are fixedly connected to the inner wall of the ash cleaning plate (10).

2. A flue gas waste heat recovery boiler for removing Fe-containing dust according to claim 1, characterized in that: One end of the smoke inlet pipe (4) extends into the dust removal cylinder (1), one end of the guide pipe (7) extends into the waste heat furnace body (2), the heat exchange tubes (9) are curved, two fixed support rods (12) are provided on the outer surface of the heat exchange tubes (9), and one end of the fixed support rod (12) is fixedly connected to the inner wall of the waste heat furnace body (2).

3. The flue gas waste heat recovery boiler for removing Fe-containing dust according to claim 1, characterized in that: The iron-containing dust fume conveyed by the centrifugal exhaust fan (3) forms an outer vortex (5) rotating downward in the upper cylinder portion of the dust removal cylinder (1), while the purified fume from which the iron-containing dust has been removed forms an inner vortex (6) spiraling upward in the lower cone portion of the dust removal cylinder (1).

4. The flue gas waste heat recovery boiler for removing Fe-containing dust according to claim 1, characterized in that: A support plate (13) is fixedly connected to the inner wall of the waste heat furnace body (2); a screw rod (14) is rotatably connected to the top of the support plate (13) via a bearing, and the screw rod (14) is located in the waste heat furnace body (2); a movable seat (15) is threadedly connected to the surface of the screw rod (14), and a side surface of the movable seat (15) is fixedly connected to one end of the cleaning plate (10); a guide rod (18) is fixedly connected to the upper surface of the support plate (13), and the guide rod (18) is fixed to one side of the screw rod (14).

5. The flue gas waste heat recovery boiler for removing Fe-containing dust according to claim 1, characterized in that: A fixing frame (16) is fixedly connected to the top of the waste heat furnace body (2), and the fixing frame (16) is U-shaped. A servo motor (17) is fixedly mounted on the top of the fixing frame (16).

6. The flue gas waste heat recovery boiler for removing Fe-containing dust according to claim 1, characterized in that: The cleaning plate (10) moves on the surface of the heat exchange tubes (9), and the silicon nitride ceramic scraper (11) is made of silicon nitride ceramic material.

7. The flue gas waste heat recovery boiler for removing Fe-containing dust according to claim 1, characterized in that: A dust collecting pipe (19) is fixedly connected to the bottom end of the dust removal cylinder (1), a fixing sleeve (20) is threadedly fixed to the outer surface of the dust collecting pipe (19), one end of the fixing sleeve (20) is fixedly connected to a dust filter bag (21), and an ash discharge port (22) is embedded in the bottom of the waste heat furnace body (2), and the ash discharge port (22) is used to collect dust accumulated on the surface of the heat exchange tube array (9).

8. The flue gas waste heat recovery boiler for removing Fe-containing dust according to claim 1, characterized in that: A plurality of support legs (23) are fixedly connected to the outer surface of the dust removal cylinder (1); the input end of the centrifugal exhaust fan (3) is connected to a dust-containing smoke pipe (24); one end of the heat exchange tube (9) is provided with a water inlet (25); the other end of the heat exchange tube (9) is provided with a water outlet (26); and both ends of the heat exchange tube (9) extend to the outside of the waste heat furnace body (2).

Images