A kind of anti-blocking structure for steelmaking flue gas heat exchanger

Abstract

The utility model provides a kind of for steelmaking flue gas heat exchanger anti-blocking structure, belongs to heat exchanger anti-blocking technical field, and includes: shell, upper tube sheet, lower tube sheet, heat exchange tube and guide ash structure;Upper tube sheet and lower tube sheet are respectively arranged in the upper end and lower end of shell, and multiple tube holes are equipped on upper tube sheet and lower tube sheet, and the both ends of heat exchange tube are respectively communicated with the tube hole of upper tube sheet and lower tube sheet;Guide ash structure includes multiple guide ash parts, and guide ash part is set on upper tube sheet and is opposite with the position of tube hole, so that furnace ash enters heat exchange tube along guide ash part;By setting guide ash part, furnace dust on tube sheet is guided, avoid the situation that furnace dust is sintered into block and blocks tube hole at tube hole edge, and the flow distribution of flue gas in tube sheet area is optimized, reduce the local airflow obstruction caused by furnace dust accumulation, to avoid the formation of local high temperature point, and then reduce explosion risk.

Description

Technical Field

[0001] This utility model belongs to the field of heat exchanger anti-clogging technology, specifically relating to an anti-clogging structure for steelmaking flue gas heat exchangers. Background Technology

[0002] Converter flue gas from steelmaking is an important source of low-cost energy for steel companies. The flue gas generated during steelmaking reaches temperatures as high as 1450-1600℃, and even after cooling through the vaporization flue, it still reaches 700-1000℃. The flue gas contains a large amount of furnace dust, with an ash content of 150-200 mg / cubic meter. However, in existing technologies, when the high-temperature flue gas flows through the heat exchanger, the furnace dust carried in the flue gas will be deposited on the tube sheet of the heat exchanger due to gravity, changes in airflow velocity, or local turbulence. Since the furnace dust contains unburned carbon particles, metal oxides, and corrosive components, these dust particles are prone to chemical reactions or physical sintering in high-temperature environments, especially at the edges of the tube holes, gradually forming a hard scale layer. This scale layer not only blocks the tube holes but also significantly reduces the heat exchange efficiency.

[0003] In existing technologies, the interior of the heat exchanger is generally cleaned by a cleaning mechanism. However, the cleaning mechanism cannot completely remove the furnace dust on the tube sheet. After long-term operation, the furnace dust is affected by temperature and material activity, and it sinters into lumps, causing the heat exchange tubes to become blocked. Furthermore, the furnace dust remaining around the tube holes on the tube sheet sinters into lumps, resulting in uneven flue gas flow, forming local high-temperature points, which exacerbates the risk of agglomeration and explosion. Utility Model Content

[0004] Based on the above-mentioned technical problems, the purpose of this utility model is to provide an anti-clogging structure for steelmaking flue gas heat exchangers. By setting up a dust guide section to guide the furnace dust on the tube sheet, the furnace dust is prevented from sintering into blocks at the edge of the tube hole and clogging the tube hole. The flow distribution of flue gas in the tube sheet area is optimized, reducing local airflow blockage caused by furnace dust accumulation, thereby avoiding the formation of local high temperature points and reducing the risk of explosion.

[0005] The specific technical solution is as follows:

[0006] A clogging prevention structure for a steelmaking flue gas heat exchanger includes: a shell, an upper tube sheet, a lower tube sheet, heat exchange tubes, and an ash guiding structure; the upper and lower tube sheets are respectively disposed at the upper and lower ends of the shell, and both the upper and lower tube sheets are provided with multiple tube holes, with the two ends of the heat exchange tubes respectively connected to the tube holes of the upper and lower tube sheets; the ash guiding structure includes multiple ash guiding sections, which are disposed on the upper tube sheet and opposite to the tube holes, allowing furnace ash to enter the heat exchange tubes along the ash guiding sections; the top of the shell is provided with a flue gas inlet, and the bottom of the shell is provided with a flue gas outlet and a slag outlet, whereby high-temperature flue gas flows through the flue gas inlet into the heat exchange tubes and exchanges heat with cold water, and the heat-exchanged flue gas is discharged through the flue gas outlet, and the furnace ash is discharged through the slag outlet; the two sides of the shell are respectively provided with a water inlet and a water outlet.

[0007] In addition, one of the anti-clogging structures for steelmaking flue gas heat exchangers provided by this utility model may also have the following additional technical features:

[0008] In the above technical solution, the dust guiding part is hexagonal, and both the inner and outer walls of the dust guiding part are inclined.

[0009] In the above technical solution, the dust guiding part is made of cast steel or cast stone mortar.

[0010] In the above technical solution, the inclination angles of the inner and outer walls of the dust guide are both 45-60 degrees.

[0011] In the above technical solution, the smoke inlet of the shell is connected to the high-temperature flue, and the smoke outlet of the shell is connected to the dust removal system.

[0012] The present invention provides an anti-clogging structure for a steelmaking flue gas heat exchanger, which, compared with the prior art, has the following advantages:

[0013] 1. By setting a dust guide on the outside of the tube hole, the furnace dust on the tube sheet is guided to slide into the heat exchange tube, avoiding the accumulation of furnace dust around the tube hole. The furnace dust can directly enter the heat exchange tube and flow with the flue gas, thereby avoiding the situation where the furnace dust sinters into blocks at the edge of the tube hole and blocks the tube hole.

[0014] 2. The ash guiding part is made of cast steel, which enables it to withstand high-temperature flue gas and corrosive dust environment, and has strong wear resistance to avoid wear caused by furnace ash erosion. It can still maintain the ash guiding function after long-term operation.

[0015] 3. The dust guide section optimizes the flow distribution of flue gas in the tube sheet area, reduces local airflow blockage caused by furnace dust accumulation, thereby avoiding the formation of local high-temperature points and reducing the risk of explosion. Attached Figure Description

[0016] Figure 1 This is a structural diagram of an anti-clogging structure for a steelmaking flue gas heat exchanger according to the present invention;

[0017] Figure 2 This is a schematic diagram of the upper tube sheet of this utility model;

[0018] Figure 3 This is a cross-sectional view of the dust guiding part of this utility model;

[0019] Figure 4 A process flow diagram for converter flue gas treatment;

[0020] in, Figures 1 to 4 The correspondence between the reference numerals and component names in the attached drawings is as follows:

[0021] 10 Shell, 11 Upper tube sheet, 12 Lower tube sheet, 13 Heat exchange tube, 14 Tube hole, 15 Ash guide section, 16 Flue gas inlet, 17 Flue gas outlet, 18 Slag outlet, 19 Water inlet, 20 Water outlet, 21 Baffle plate. Detailed Implementation

[0022] The following are specific implementation cases and appendices. Figure 1-4 The present invention will be further described below, but the present invention is not limited to these embodiments.

[0023] An anti-clogging structure for a steelmaking flue gas heat exchanger, as shown in Figures 1-4, includes: a shell 10, an upper tube sheet 11, a lower tube sheet 12, heat exchange tubes 13, and an ash guiding structure; the upper tube sheet 11 and the lower tube sheet 12 are respectively disposed at the upper and lower ends of the shell 10, and both the upper tube sheet 11 and the lower tube sheet 12 are provided with multiple tube holes 14, and both ends of the heat exchange tubes 13 are respectively connected to the tube holes 14 of the upper tube sheet 11 and the lower tube sheet 12; the ash guiding structure includes multiple ash guiding parts 15 for guiding ash. The part 15 is set on the upper tube plate 11 and is opposite to the position of the tube hole 14, so that the furnace ash enters the heat exchange tube 13 along the ash guide part 15; the top of the shell 10 is provided with a flue gas inlet 16, and the bottom of the shell 10 is provided with a flue gas outlet 17 and a slag outlet 18. The high temperature flue gas flows into the heat exchange tube 13 through the flue gas inlet 16 and exchanges heat with cold water. The flue gas after heat exchange is discharged through the flue gas outlet 17, and the furnace ash is discharged through the slag outlet 18; the two sides of the shell 10 are respectively provided with a water inlet 19 and a water outlet 20.

[0024] By adopting the above structure, the furnace dust on the tube sheet is guided by the dust guide part 15 set on the outside of the tube hole 14, so that the furnace dust slides into the heat exchange tube 13, avoiding the accumulation of furnace dust around the tube hole 14, and allowing the furnace dust to directly enter the heat exchange tube 13 and flow with the flue gas, thereby avoiding the situation where the furnace dust sinters into blocks at the edge of the tube hole 14 and blocks the tube hole 14.

[0025] By utilizing the smooth and inclined surface of the dust guide section 15, dust can slide smoothly on the surface, making it less prone to accumulation. Furthermore, the dust guide section 15 is installed around the tube holes 14 and located in the gaps between adjacent tube holes 14, effectively preventing furnace dust from accumulating on the tube sheet. The structure of the dust guide section 15 optimizes the flow distribution of flue gas in the tube sheet area, reducing local airflow blockage caused by furnace dust accumulation, thereby preventing the formation of localized high-temperature points and reducing the risk of explosion.

[0026] The inlet 16 is used to connect to the high-temperature flue and introduce the steelmaking flue gas to be cooled; the outlet 17 is connected to the dust removal system and discharges the low-temperature flue gas after heat exchange; the slag outlet 18 is used to discharge the furnace dust that has settled or flowed down; the inlet 19 and outlet 20 on both sides of the shell 10 are used for the inflow of cold water and the outflow of water after heat exchange.

[0027] High-temperature flue gas enters from the flue gas inlet 16 at the top of the shell 10. When the flue gas encounters the ash guide section 15, the furnace ash in the flue gas enters the heat exchange tube 13 along the ash guide section 15. Inside the heat exchange tube 13, the high-temperature flue gas exchanges heat with the cooling water flowing outside the tube, reducing the temperature of the flue gas. The cooled flue gas, carrying some fine ash, is discharged from the exhaust port 17 at the bottom and enters the subsequent dust removal system. The coarser or settled furnace ash falls to the bottom of the shell 10 along the ash guide structure and the heat exchange tube 13, and is finally discharged through the slag discharge port 18.

[0028] Specifically, the process flow of the steelmaking converter flue gas recovery system is as follows: converter - movable fume hood - vaporization flue sections I, II, and III - flue gas pre-processor - high-temperature flue - heat exchanger - dust removal system. Among them, the temperature of the high-temperature flue gas discharged from vaporization flue sections I, II, and III is 700-1000℃, and the temperature of the flue gas discharged from the heat exchanger is 170-220℃.

[0029] By setting up a dust guiding structure, large particles of furnace dust in the flue gas can be guided to enter the heat exchange tubes along the dust guiding structure, reducing the accumulation of furnace dust on the tube sheet, thereby extending the cleaning cycle of the heat exchanger and reducing the losses from downtime maintenance.

[0030] Specifically, the casing 10 is also equipped with a baffle 21 to increase the heat exchange time between cold water and flue gas.

[0031] In an embodiment of this utility model, the dust guiding part 15 is hexagonal, and both the inner and outer walls of the dust guiding part 15 are inclined.

[0032] By designing the ash guide section 15 as a hexagon, there are no gaps between adjacent tube holes 14. Therefore, no matter where the furnace dust falls on the upper tube plate 11, it can fall into the tube hole 14 through the inner or outer wall of the ash guide section 15.

[0033] In an embodiment of this utility model, the dust guiding part 15 is made of cast steel or cast stone putty.

[0034] By utilizing the high temperature resistance and wear resistance of cast steel, it can withstand high temperature environments and the scouring of furnace ash, thereby reducing the wear of the ash guide section 15.

[0035] The dust guide section 15 can also be made of cast stone mortar to improve its wear resistance, corrosion resistance and high temperature resistance.

[0036] In an embodiment of this utility model, the angle of the sidewall of the dust guide part 15 is 45-60 degrees.

[0037] By setting the angle of inclination of the inner and outer walls of the dust guide 15 to 45-60 degrees, the dust is ensured to slide off effectively and smoothly under the action of gravity.

[0038] In an embodiment of this utility model, the smoke inlet 16 of the housing 10 is connected to a high-temperature flue, and the smoke outlet 17 of the housing 10 is connected to a dust removal system.

[0039] Implementation process: High-temperature flue gas enters from the flue gas inlet 16 at the top of the shell 10. Upon encountering the ash guide section 15, the ash in the flue gas flows along the ash guide section 15 into the heat exchange tube 13. Inside the heat exchange tube 13, the high-temperature flue gas exchanges heat with the cooling water flowing outside the tube, reducing the flue gas temperature. The cooled flue gas, carrying some fine ash, is discharged from the exhaust port 17 at the bottom and enters the subsequent dust removal system. Coarser or settled ash falls to the bottom of the shell 10 along the ash guide structure and the heat exchange tube 13, and is finally discharged through the slag discharge port 18. By setting the ash guide section 15 on the outside of the tube hole 14 to guide the ash on the tube sheet, the ash slides into the heat exchange tube 13, preventing the ash from accumulating around the tube hole 14. This allows the ash to directly enter the heat exchange tube 13 and flow with the flue gas, thus preventing the ash from sintering into clumps at the edge of the tube hole 14 and blocking it.

[0040] In the description of this utility model, the term "multiple" refers to two or more. Unless otherwise explicitly defined, the terms "upper," "lower," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. The terms "connection," "installation," "fixing," etc., should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection or an indirect connection through an intermediate medium. For those skilled in the art, the specific meaning of the above terms in this utility model can be understood according to the specific circumstances.

[0041] The above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A structure for preventing blockage in a steelmaking flue gas heat exchanger, characterized in that, include: The system comprises a shell, an upper tube sheet, a lower tube sheet, heat exchange tubes, and an ash guiding structure. The upper and lower tube sheets are respectively located at the upper and lower ends of the shell. Both the upper and lower tube sheets have multiple tube holes, and the two ends of the heat exchange tubes are connected to the tube holes of the upper and lower tube sheets, respectively. The ash guiding structure includes multiple ash guiding sections, which are located on the upper tube sheet and opposite to the tube holes, allowing furnace ash to enter the heat exchange tubes along the ash guiding sections. The top of the shell has a flue gas inlet, and the bottom of the shell has a flue gas outlet and a slag outlet. High-temperature flue gas flows through the flue gas inlet into the heat exchange tubes and exchanges heat with cold water. The flue gas after heat exchange is discharged through the flue gas outlet, and the furnace ash is discharged through the slag outlet. The two sides of the shell have water inlets and outlets, respectively.

2. The anti-clogging structure for a steelmaking flue gas heat exchanger according to claim 1, characterized in that, The dust guiding part is hexagonal, and both the inner and outer walls of the dust guiding part are inclined.

3. The anti-clogging structure for a steelmaking flue gas heat exchanger according to claim 1, characterized in that, The dust guiding part is made of cast steel or cast stone mortar.

4. The anti-clogging structure for a steelmaking flue gas heat exchanger according to claim 2, characterized in that, The angles of inclination of the inner and outer walls of the dust guiding section are both 45-60 degrees.

5. The anti-clogging structure for a steelmaking flue gas heat exchanger according to claim 1, characterized in that, The inlet of the casing is connected to a high-temperature flue, and the outlet of the casing is connected to a dust removal system.

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