Multi-pressure steam superheater

Abstract

The utility model discloses a multi-pressure steam superheater, which relates to the technical field of superheaters, and comprises a hearth which is of an n-shaped arrangement structure and comprises a heat insulation flue of a burner outlet, a burner arranged at the front end of the heat insulation flue, and a convection heating surface arranged at the outlet of the heat insulation flue. A high-pressure superheater II, a high-pressure superheater I, a medium-pressure superheater II, a medium-pressure superheater I, a low-pressure superheater II, a low-pressure superheater I, a low-low pressure superheater, a steering flue, a tubular air preheater and an outlet flue are sequentially arranged in the convection heating surface; a high-pressure superheater spray desuperheater is arranged in a pipeline between the high-pressure superheater I and the high-pressure superheater II, a medium-pressure superheater spray desuperheater is arranged in a pipeline between the medium-pressure superheater I and the medium-pressure superheater II, and a low-pressure superheater spray desuperheater is arranged in a pipeline between the low-pressure superheater I and the low-pressure superheater II. According to the utility model, the multi-pressure steam overheating condition under various process links of a coal chemical system can be met, the pipe is convenient to block or replace, and meanwhile, the pipe panel is not easy to deform due to overtemperature.

Description

Technical Field

[0001] This utility model relates to the field of superheated furnace technology, and in particular to a multi-pressure steam superheated furnace. Background Technology

[0002] Superheaters are widely used in the coal chemical industry, particularly in catalytic cracking, styrene, ammonia synthesis, and methanol plants. Their main function is to superheat saturated steam, improving its quality to provide heat for downstream equipment such as reactors, or to drive turbines. The superheater operates by using the high-temperature flame and flue gas generated during fuel combustion as a heat source to heat the medium flowing through the furnace tubes, bringing it to the specified process temperature. Fuel is ejected from the burner and combusted, producing a high-temperature flame and flue gas. The high-temperature flue gas rises into the convection chamber of the superheater due to the draft from the chimney or the action of the induced draft fan, transferring heat to the furnace tubes within the convection chamber and subsequently to the medium inside the tubes.

[0003] The existing superheated furnaces in the coal chemical industry have the following problems: (1) The existing superheated furnace systems generally use steam from a single source, which cannot meet the multi-pressure steam requirements of various processes such as coal gasification, coal-to-natural gas, and coal-to-oil in the chemical system. (2) Most of the convective heating surfaces of the superheated furnace are serpentine tube screen structures, which are inconvenient to block or replace in case of leakage or tube rupture. (3) The flue gas temperature generated by the burner is too high, and the front row of serpentine tubes is prone to deformation. (4) Due to the limitations of the process conditions of each system, the supply of saturated steam is unstable, and the tube screens of each heating surface are prone to overheating and damage or deformation. Utility Model Content

[0004] To solve the above-mentioned technical problems, this utility model designs a multi-pressure steam superheater.

[0005] The present invention adopts the following technical solution:

[0006] A multi-pressure steam superheater includes a furnace chamber with a Π-shaped arrangement, comprising an insulated flue at the burner outlet. The insulated flue is a horizontally arranged flue structure. A burner is arranged at the front end of the insulated flue, and a convective heating surface is arranged at the outlet of the insulated flue. Within the convective heating surface, a high-pressure superheater II, a high-pressure superheater I, a medium-pressure superheater II, a medium-pressure superheater I, a low-pressure superheater II, a low-pressure superheater I, a low-low-pressure superheater, a diverting flue, a tubular air preheater, and an outlet flue are arranged sequentially. A high-pressure superheater water spray desuperheater is arranged in the pipe between high-pressure superheaters I and II, a medium-pressure superheater water spray desuperheater is arranged in the pipe between medium-pressure superheaters I and II, and a low-pressure superheater water spray desuperheater is arranged in the pipe between low-pressure superheaters I and II.

[0007] Preferably, an SCR reserved flue is provided between the diversion flue and the tubular air preheater.

[0008] Preferably, the serpentine tubes of the heating surfaces of the high-pressure superheater II, high-pressure superheater I, medium-pressure superheater II, medium-pressure superheater I, low-pressure superheater II, low-pressure superheater I, and low-low-pressure superheater adopt a tube box structure.

[0009] Preferably, the serpentine pipe has a sleeve structure at the wall penetration point, and the elbow on the outside of the pipe sheet is welded separately.

[0010] Preferably, the tubular air preheater is arranged in a three-stage vertical configuration.

[0011] Preferably, the number of burners is 3 to 4.

[0012] The beneficial effects of this utility model are as follows: This utility model provides a novel multi-pressure steam superheater system that can meet the multi-pressure steam superheating requirements of various process stages in coal chemical systems; the heating surface adopts a tube box structure, which facilitates tube plugging or replacement in case of leakage or tube rupture; 3-4 multi-fuel burners are arranged at the front end, with a wide range of combustion gas sources, and the flue gas flow and temperature can be adjusted according to different operating conditions, with a wide adjustment range to adapt to various operating conditions; each stage of superheater has two sets of tube panels, which are made of high-temperature resistant materials, and water spray desuperheaters are arranged between the tube panels for adjustment, so the tube panels are not prone to overheating and deformation. At the same time, the tube panels can also be split and merged according to the amount and temperature of incoming steam. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the structure of the device of this utility model;

[0014] Figure 2 This is a schematic diagram of the flue gas system of the device of this utility model;

[0015] Figure 3 This is a schematic diagram of the steam and water system of the device of this utility model;

[0016] In the diagram: 1. Burner, 2. Insulated flue, 3. High-pressure superheater II, 4. High-pressure superheater I, 5. Medium-pressure superheater II, 6. Medium-pressure superheater I, 7. Low-pressure superheater II, 8. Low-pressure superheater I, 9. Low-low-pressure superheater, 10. Diverting flue, 11. SCR reserved flue, 12. Tubular air preheater, 13. Outlet flue, 14. High-pressure superheater spray desuperheater, 15. Medium-pressure superheater spray desuperheater, 16. Low-pressure superheater spray desuperheater. Detailed Implementation

[0017] The technical solution of this utility model will be further described in detail below through specific embodiments and with reference to the accompanying drawings:

[0018] Example: Figures 1-3As shown, a multi-pressure steam superheater includes an insulated flue 2, which is a horizontally arranged flue structure. The flue 2 is long enough to allow the fuel to burn completely in the insulated flue 2. When the flue gas after combustion enters the vertical heating surface, the temperature deviation of the flue gas at each point is small, so as to avoid uneven heating of the heating surface.

[0019] The front of the insulated flue 2 is equipped with 3-4 burners 1. Using multiple burners provides a wide load adjustment range, allowing the use of fuel gas, as well as stabilizer tower exhaust gas, PSA desorption gas, and other process byproducts from coal chemical production. The combustion air is divided into two parts: one part is the waste gas supplied from the plant to the steam superheater. This waste gas can be pressurized and fed separately to the burners from the HDPE unit, Unipol unit, Spherizone unit, and other units in the coal chemical process, or combined and fed into the burners via a booster fan; the other part is air, supplemented by a separately installed blower. This fully utilizes byproducts from coal chemical production for recycling and reuse, reducing resource waste.

[0020] The outlet of the insulated flue 2 is arranged with a convective heating surface. The convective heating surface is arranged in sequence with high pressure superheater II 3, high pressure superheater I 4, medium pressure superheater II 5, medium pressure superheater I 6, low pressure superheater II 7, low pressure superheater I 8, low-low pressure superheater 9, turning flue 10, tubular air preheater 12, and outlet flue 13.

[0021] The flue gas, which is uniformly mixed in the insulated flue 2, passes sequentially through the heating surfaces of the high-pressure superheater II 3, the high-pressure superheater I 4, the medium-pressure superheater II 5, the medium-pressure superheater I 6, the low-pressure superheater II 7, the low-pressure superheater I 8, the low-low-pressure superheater 9, the turning flue 10, and the tubular air preheater 12, and then enters the chimney or other equipment through the outlet flue 13.

[0022] The high-pressure superheater spray desuperheater 14 is arranged in the connecting pipe between the heating surface 4 of high-pressure superheater I and the heating surface 3 of high-pressure superheater II. For example... Figure 3 As shown, high-pressure saturated steam is heated sequentially by high-pressure superheater I4 and high-pressure superheater II3. The high-pressure superheater spray desuperheater 14 can adjust the outlet steam temperature of high-pressure superheater I4 to ensure that the outlet parameters of high-pressure superheater II3 meet the design requirements.

[0023] The intermediate-pressure superheater spray desuperheater 15 is arranged in the connecting pipe between the heating surface 6 of intermediate-pressure superheater I and the heating surface 5 of intermediate-pressure superheater II. For example... Figure 3 As shown, medium-pressure saturated steam is heated sequentially by medium-pressure superheater I6 and medium-pressure superheater II5. The medium-pressure superheater spray desuperheater 15 can regulate the outlet steam temperature of medium-pressure superheater I6 to ensure that the outlet parameters of medium-pressure superheater II5 meet the design requirements.

[0024] The low-pressure superheater spray desuperheater 16 is arranged in the connecting pipe between the heating surface 8 of low-pressure superheater I and the heating surface 7 of low-pressure superheater II. For example... Figure 3 As shown, low-pressure saturated steam is heated sequentially by passing through low-pressure superheater I8 and low-pressure superheater II7. The low-pressure superheater spray desuperheater 16 can adjust the outlet steam temperature of low-pressure superheater I8 to ensure that the outlet parameters of low-pressure superheater II7 meet the design requirements.

[0025] Furthermore, an SCR reserved flue 11 is provided between the diversion flue 10 and the tubular air preheater 12. The SCR reserved flue 11 can be used to arrange the SCR reactor according to the parameters after fuel combustion, so that the outlet NOx index meets the corresponding emission standards.

[0026] Furthermore, the serpentine tubes of the high-pressure superheater II3, high-pressure superheater I4, medium-pressure superheater II5, medium-pressure superheater I6, low-pressure superheater II7, low-pressure superheater I8, and low-low-pressure superheater 9 adopt a tube box structure, with sleeve structures at the wall penetration points of the serpentine tubes. The elbows on the outer side of the tube sheet are welded separately. With this structure, when a tube inside the flue is damaged and needs replacement, the straight section of the tube can be removed and replaced instead of replacing the entire tube panel, reducing maintenance cycles and saving on tube panel costs.

[0027] Furthermore, a tubular air preheater 12 is adopted at the tail end. The tubular air preheater 12 adopts a three-stage vertical arrangement. During the design, the size and quantity can be adjusted appropriately according to the flue gas temperature at the front.

[0028] Furthermore, the tubes of the high-pressure superheater II3, high-pressure superheater I4, medium-pressure superheater II5, medium-pressure superheater I6, low-pressure superheater II7, low-pressure superheater I8, and low-low-pressure superheater 9 are made of high-temperature resistant materials. The first set of heating surfaces through which the flue gas flows, high-pressure superheater II3 and high-pressure superheater I4, can be made of heat-resistant steel materials such as HR3C and Super304H. Subsequent heating surfaces can be made of materials such as TP347H and TP304H. This reduces the effects of creep, thermal fatigue, high-temperature corrosion, and easy overheating damage or deformation of the tube and screen materials of each heating surface during long-term operation at high temperature and high pressure or under unstable saturated steam conditions, thereby extending the equipment life and ensuring operational safety.

[0029] The embodiments described above are merely preferred solutions of this utility model and are not intended to limit this utility model in any way. Other variations and modifications are possible without departing from the technical solutions described in the claims.

Claims

1. A multi-pressure steam superheater furnace, comprising a furnace chamber, characterized in that, The furnace has a Π-shaped layout and includes an insulated flue at the burner outlet. The insulated flue is a horizontally arranged flue structure. The burner is located at the front end of the insulated flue, and a convective heating surface is located at the outlet of the insulated flue. Within the convective heating surface, a high-pressure superheater II, a high-pressure superheater I, a medium-pressure superheater II, a medium-pressure superheater I, a low-pressure superheater II, a low-pressure superheater I, a low-low-pressure superheater, a turning flue, a tubular air preheater, and an outlet flue are arranged in sequence. A high-pressure superheater water spray desuperheater is arranged in the pipe between high-pressure superheaters I and II, a medium-pressure superheater water spray desuperheater is arranged in the pipe between medium-pressure superheaters I and II, and a low-pressure superheater water spray desuperheater is arranged in the pipe between low-pressure superheaters I and II.

2. The multi-pressure steam superheater according to claim 1, characterized in that, An SCR reserved flue is provided between the diversion flue and the tubular air preheater.

3. The multi-pressure steam superheater according to claim 1, characterized in that, The heating surfaces of the high-pressure superheater II, high-pressure superheater I, medium-pressure superheater II, medium-pressure superheater I, low-pressure superheater II, low-pressure superheater I, and low-low-pressure superheater adopt a tube box structure.

4. A multi-pressure steam superheater according to claim 3, characterized in that, The serpentine pipe has a sleeve structure at the wall penetration point, and the elbow on the outside of the pipe sheet is welded separately.

5. A multi-pressure steam superheater according to claim 1, characterized in that, The tubular air preheater is arranged in a three-stage vertical configuration.

6. A multi-pressure steam superheater according to claim 1, characterized in that, The number of burners is 3 to 4.

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