Full-dry process system for converter flue gas waste heat recovery
Through a fully dry process system, the heat energy exchange between the converter flue gas and deoxygenated water is solved, and the problems of high energy consumption, large water consumption and low heat recovery efficiency in the prior art are solved, and efficient water resource utilization and low energy consumption heat recovery are achieved.
Patent Information
- Application Number
- CN202421564464.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-07-03
- Publication Date
- 2025-04-29
- Estimated Expiration
- 2034-07-03
AI Technical Summary
The existing converter flue gas waste heat recovery process has problems such as high energy consumption, large water consumption and low heat recovery efficiency, and it is easy to block the screen plate after long-term operation.
The fully dry process system is adopted, and the converter flue gas and deoxygenated water are heat exchanged through an adiabatic flue gas heat exchanger. The heat-raising deoxygenated water is input to the steam heat storage and steady flow device for steady flow and pressure storage, and low-pressure saturated steam is generated for heat recovery.
It has achieved water resources conservation, reduced environmental pollution, improved the efficiency of waste heat utilization of converter flue gas, and reduced energy consumption and carbon dioxide emissions.
Smart Images
Figure CN222809497U_ABST
Abstract
Description
Technical Field
[0001] The utility model belongs to the technical field of flue gas waste heat, in particular to a full dry process system for recovering converter flue gas waste heat. Background Art
[0002] During the steelmaking process, the converter will produce a large amount of flue gas, the main components of which are high-concentration carbon monoxide and dust particles. First, the flue gas must be purified and dust-removed. Secondly, the flue gas temperature is high, and the flue gas waste heat must be recycled. The converter flue gas after purification and waste heat recovery can be used as fuel, that is, converter gas. At present, the process methods for recovering waste heat from converter flue gas are mainly OG method and LT method. The OG method adopts a wet process, which consumes more energy and water per ton of steel. Although it has been continuously improved in terms of saving electricity, saving water and improving dust removal efficiency, the existing problems have not been fundamentally changed. For example, direct water spraying for cooling wastes water resources, causes water pollution and reduces the calorific value of coal gas, and the high-temperature waste heat at the outlet of the vaporization cooling flue is not recovered. The LT method uses quantitative spraying to cool the converter flue gas, and uses the latent heat of evaporation of water to cool down. It has low energy consumption and high dust removal efficiency, but low heat recovery efficiency. Therefore, the existing converter flue gas waste heat recovery and purification process has high energy consumption, large water consumption, relatively small amount of recovered coal gas, molten particles in the converter flue gas, incomplete dust removal will affect the flue gas heat recovery efficiency, and long-term operation will easily clog the screen plate. Utility Model Content
[0003] In order to solve the problems of high energy consumption and large water consumption in the process of converter flue gas waste heat recovery and purification in the prior art, the utility model provides a full dry process system for converter flue gas waste heat recovery.
[0004] In order to achieve the above purpose, the utility model provides the following technical solutions:
[0005] The utility model discloses a full dry process system for recovering waste heat from converter flue gas, comprising a converter, wherein the converter flue gas outlet is connected to the flue gas inlet of an adiabatic flue gas heat exchanger, the flue gas outlet of the adiabatic flue gas heat exchanger is connected to the air inlet of a primary dust collector, the air outlet of the primary dust collector is connected to the flue gas inlet of a low-temperature fine dust collector, the flue gas outlet of the low-temperature fine dust collector is connected to an interface of a three-way switching valve, and the other two interfaces of the three-way switching valve are respectively connected to a gas cabinet and a gas dispersing self-combustion system;
[0006] The gas cabinet is used to deliver qualified gas to gas users, and the gas emission self-combustion system is used to burn and discharge unqualified gas;
[0007] The adiabatic flue gas heat exchanger is provided with a deoxygenated water inlet and a steam outlet, the deoxygenated water inlet is connected to a deoxygenated water supply device; the steam outlet is connected to the inlet end of a steam heat storage and flow stabilization device, and the outlet end of the steam heat storage and flow stabilization device is connected to a steam pipe network.
[0008] Preferably, a coil is provided on the adiabatic flue gas heat exchanger, one end port of the coil is connected to the deoxygenated water inlet, and the other end port of the coil is connected to the steam outlet.
[0009] Preferably, a heat insulating protective layer is provided on the adiabatic flue gas heat exchanger outside the coil.
[0010] Preferably, the gas outlet of the primary dust collector is connected to the flue inlet of the explosion-proof heat pipe waste heat boiler, and the flue outlet of the explosion-proof heat pipe waste heat boiler is connected to the flue gas inlet of the low-temperature fine dust collector;
[0011] The explosion-proof heat pipe waste heat boiler is provided with an inlet pipe and a steam outlet pipe, the inlet pipe is connected to the deoxygenated water supply equipment, and the steam outlet pipe is connected to the inlet end of the steam heat storage stabilizing flow device.
[0012] Preferably, the heat exchange tubes in the explosion-proof heat pipe waste heat boiler are finned heat exchange tubes.
[0013] Preferably, the dust content in the flue gas output by the low-temperature fine dust collector is less than 10 mg / m 3 .
[0014] Preferably, the low-temperature fine dust collector is an electrostatic precipitator or a bag dust collector.
[0015] Preferably, a dust recovery device is connected to the primary dust collector.
[0016] Preferably, the primary dust collector is a cyclone structure dust collector.
[0017] Preferably, the steam heat storage and flow stabilization device is a steam accumulator.
[0018] Compared with the prior art, the utility model has the following beneficial technical effects:
[0019] The utility model discloses a full dry process system for recovering waste heat from converter flue gas. The system exchanges heat energy between converter flue gas and deoxygenated water in an adiabatic flue gas heat exchanger, and then inputs the heated deoxygenated water into a steam heat storage and flow stabilization device for flow stabilization and pressure storage, and then generates low-pressure saturated steam and delivers it to the steam network for use. The heat exchange process is a full dry waste heat recovery process, and there is no water process. Compared with the traditional form of water spray cooling, it greatly saves water resources and reduces environmental pollution. At the same time, heat is recovered, and waste of flue gas heat is avoided, which greatly improves the utilization efficiency of converter flue gas waste heat. At the same time, the converter flue gas after the heat exchange is dedusted by a primary dust collector and a low-temperature fine dust collector, and then the gas containing qualified coal gas is delivered to the coal gas user, and the gas containing unqualified coal gas is delivered to the gas self-combustion system for treatment and emission, which effectively reduces energy consumption, reduces carbon dioxide emissions, and achieves energy conservation and emission reduction.
[0020] Furthermore, in the system, a coil is provided on the adiabatic flue gas heat exchanger, and the deoxygenated water input into the adiabatic flue gas heat exchanger is gradually heated through the coil to improve the heat energy exchange efficiency. At the same time, an insulating protective layer is provided outside the coil on the adiabatic flue gas heat exchanger to insulate the coil through the insulating protective layer, thereby reducing the heat exchange between the coil and the external air and reducing heat loss.
[0021] Furthermore, in the present system, an explosion-proof heat pipe type waste heat boiler is connected between the air outlet of the primary dust collector and the flue gas inlet of the low-temperature fine dust collector. Deoxygenated water is passed through the explosion-proof heat pipe type waste heat boiler. The deoxygenated water flows in the finned heat exchange tubes in the explosion-proof heat pipe type waste heat boiler, thereby increasing the area for heat energy exchange between the deoxygenated water and the converter flue gas. The heat energy in the converter flue gas is again exchanged with the deoxygenated water through the explosion-proof heat pipe type waste heat boiler to generate steam for utilization, thereby greatly improving the utilization efficiency of the converter flue gas waste heat.
[0022] Furthermore, the dust content in the flue gas output by the low-temperature fine dust collector in this system is less than 10mg / m 3 The low-temperature fine dust collector is an electrostatic precipitator or a bag dust collector. Through the fine filtration of the electrostatic precipitator or the bag dust collector, the dust content of the output flue gas is successfully controlled to less than 10mg / m 3 The extremely low level effectively reduces the emission of air pollutants and protects the environment. BRIEF DESCRIPTION OF THE DRAWINGS
[0023] Figure 1 A schematic diagram of the connection of a full dry process system for converter flue gas waste heat recovery provided by the utility model;
[0024] In the attached figure: 1. converter; 2. adiabatic flue gas heat exchanger; 21. deoxygenated water inlet; 22. steam outlet; 23. insulation protective layer; 3. primary dust collector; 4. explosion-proof heat pipe waste heat boiler; 41. inlet pipe; 42. steam outlet pipe; 43. flue inlet; 44. flue outlet; 5. explosion-proof device; 6. low-temperature fine dust collector; 7. induced draft fan; 8. three-way switching valve; 9. gas holder; 10. gas self-combustion system; 11. gas booster station; 12. ash conveying device; 13. chimney; 14. gas user; 15. steam heat storage and flow stabilization device; 16. steam pipeline network; 17. dust recovery device. DETAILED DESCRIPTION
[0025] In the following, only some exemplary embodiments are briefly described. As those skilled in the art will appreciate, the described embodiments may be modified in various ways without departing from the spirit or scope of the present invention. Therefore, the drawings and descriptions are considered to be exemplary and non-restrictive in nature.
[0026] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.
[0027] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present utility model, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.
[0028] In the present invention, unless otherwise clearly specified and limited, the terms "install", "connect", "connect", "fix" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or a communication; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.
[0029] In the present utility model, unless otherwise clearly stipulated and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is lower in level than the second feature.
[0030] The embodiments of the present utility model are described in detail below with reference to the accompanying drawings.
[0031] See also Figure 1 The utility model discloses a full dry process system for recovering waste heat from converter flue gas, the system comprising a converter 1, the flue gas outlet of the converter 1 is connected to the flue gas inlet of an adiabatic flue gas heat exchanger 2, the flue gas outlet of the adiabatic flue gas heat exchanger 2 is connected to the air inlet of a primary dust collector 3, the air outlet of the primary dust collector 3 is connected to a flue inlet 43 arranged on an explosion-proof heat pipe waste heat boiler 4, the flue outlet 44 arranged on the explosion-proof heat pipe waste heat boiler 4 is connected to the flue gas inlet of a low-temperature fine dust collector 6, the low-temperature fine dust collector 6 is an electrostatic precipitator or a bag dust collector, the flue gas output from the explosion-proof heat pipe waste heat boiler 4 is further filtered by the electrostatic precipitator or the bag dust collector, so that the dust content in the flue gas is less than 10mg / m 3 The flue gas outlet of the low-temperature fine dust collector 6 is connected to the air inlet of the induced draft fan 7, and the air outlet of the induced draft fan 7 is connected to an interface of the three-way switching valve 8. One of the remaining two interfaces on the three-way switching valve 8 is connected to the air inlet of the gas cabinet 9, and the flue gas outlet of the gas cabinet 9 is connected to the air inlet of the gas pressure station 11. The air outlet of the gas pressure station 11 is connected to the gas user 14; the remaining interface on the three-way switching valve 8 is connected to the air inlet of the gas self-combustion system 10, and the air outlet of the gas self-combustion system 10 is connected to the chimney 13. Among them, the gas self-combustion system 10 includes equipment such as a high-energy igniter JHGN-120 and a smoke exhaust device. The gas input into the gas self-combustion system 10 through the three-way switching valve 8 is ignited by the high-energy igniter JHGN-120 to remove the gas in the gas, and then transported to the chimney 13 through the smoke exhaust device for discharge. The smoke exhaust device includes a flue, a smoke exhaust fan, a cyclone dust collector and a smoke purifier.
[0032] See also Figure 1The primary dust collector 3 is connected with an ash conveying device 12, which can clean the dust in the ash bin of the primary dust collector 3. The ash conveying device 12 is a scraper conveyor. The ash conveying device 12 is connected with a dust recovery device 17, which is a dust collection bucket. The primary dust collector 3 is a high-temperature dust collector and a cyclone structure dust collector. It removes large particles of dust in the flue gas of the converter after being treated by the flue gas heat exchanger 2, removes particulate matter, dust, etc. in the converter flue gas, and avoids dust from being eroded by the wall of the explosion-proof heat pipe waste heat boiler 4 in the subsequent process. At the same time, the primary dust collector 3 adopts a vertical structure or a horizontal structure.
[0033] See also Figure 1 The adiabatic flue gas heat exchanger 2 is a cylindrical structure heat exchanger. A deoxygenated water inlet 21 is provided on the adiabatic flue gas heat exchanger 2. The deoxygenated water inlet 21 is connected to the deoxygenated water supply equipment. A steam outlet 22 is also provided on the adiabatic flue gas heat exchanger 2. The steam outlet 22 is connected to the inlet end of the steam heat storage and flow stabilization device 15. The outlet end of the steam heat storage and flow stabilization device 15 is connected to the steam pipe network 16. A coil is provided on the outer wall of the adiabatic flue gas heat exchanger 2. One end of the coil is connected to the deoxygenated water inlet 21. Through the coil, the input deoxygenated water can fully exchange heat with the converter flue gas in the adiabatic flue gas heat exchanger 2, heat the deoxygenated water, and improve the heat exchange efficiency of the converter flue gas. An insulating protective layer 23 is provided outside the coil. The insulating protective layer 23 is used to keep the coil warm and prevent the heat loss of the deoxygenated water in the coil.
[0034] See also Figure 1 The explosion-proof heat pipe waste heat boiler 4 is provided with a steam outlet pipe 42, and the steam outlet pipe 42 is connected to the inlet end of the steam heat storage and flow stabilizing device 15; the explosion-proof heat pipe waste heat boiler 4 is provided with a steam outlet pipe 42, and an inlet pipe 41 is provided on the steam outlet pipe 42, and the inlet pipe 41 is connected to the deoxygenated water supply equipment; the explosion-proof heat pipe waste heat boiler 4 is provided with an explosion-proof device 5, and the explosion-proof device is a UTE1047 natural gas explosion-proof electric heater, wherein the heat exchange tubes in the explosion-proof heat pipe waste heat boiler 4 are finned heat exchange tubes.
[0035] The processing process of converter flue gas in this system is as follows: converter flue gas with a temperature of 1450-1550°C is generated in converter 1, and the converter flue gas is transported from the flue gas outlet of converter 1 to adiabatic flue gas heat exchanger 2, and heat energy is exchanged with the input deoxygenated water through adiabatic flue gas heat exchanger 2. After the heat energy exchange is sufficient, the heated deoxygenated water is input into steam heat storage and flow stabilization device 15, and the converter flue gas temperature is reduced to 850-1000°C after heat exchange, and then the converter flue gas with a temperature of 850-1000°C is input into primary dust collector 3 for dust removal, and the converter flue gas with a temperature of 850-1000°C in explosion-proof heat pipe waste heat boiler 4 is exchanged with the deoxygenated water. The deoxygenated water input into the explosion-proof heat pipe waste heat boiler 4 is subjected to heat energy exchange again, so that the flue gas temperature drops to 150-200°C. After the heat energy exchange, the heated deoxygenated water is input into the steam heat storage and flow stabilization device 15, and then the deoxygenated water in the steam heat storage and flow stabilization device 15 is transported to the steam network pipe 16 for use. The explosion-proof heat pipe waste heat boiler 4 inputs the converter flue gas with a temperature of 150-200°C into the low-temperature fine dust collector 6 for dust removal, thereby reducing the dust content of the converter flue gas with a temperature of 150-200°C, so that the dust content in the converter flue gas with a temperature of 150-200°C is less than 10mg / m 3 , and then transported to the three-way switching valve 8 through the induced draft fan 17. The three-way switching valve 8 is provided with a flue gas detector. Through the flue gas detector, when there is unqualified coal gas in the flue gas, the three-way switching valve 8 switches to the gas dispersing self-combustion system 10 to burn and discharge the unqualified coal gas; the flue gas discharged by combustion is discharged from the chimney 13. When there is qualified coal gas in the flue gas, the three-way switching valve 8 switches to the gas tank 9, and the gas tank 9 is pressurized through the gas pressure station 11. The gas pressure station 11 is provided with a gas mixer. Through the gas pressure station 11, the pressurized and mixed gas is transported to the gas user 14 through the pipeline for use. The system improves the utilization rate of the waste heat of the converter flue gas through two heat energy exchanges. At the same time, the gas containing qualified coal gas is transported to the gas user 14 for reuse through detection, which improves the utilization efficiency of the coal gas in the flue gas and reduces the waste of resources.
[0036] Among them, because the converter production is intermittent, and the converter flue gas changes periodically, the steam output by the adiabatic flue gas heat exchanger 2 and the steam output by the explosion-proof heat pipe waste heat boiler 4 are respectively transported to the steam heat storage and flow stabilization device 15 through steam pipes. The steam heat storage and flow stabilization device 15 can generate continuous and stable saturated steam by means of pressure reduction and the like. At the initial stage of use, more than 50% of deoxygenated water must be injected into the steam heat storage and flow stabilization device 15. The steam space above the water surface is a steam space, and a charger is installed in the water space. The steam heat storage and flow stabilization device 15 is a steam accumulator with a capacity of 200 cubic meters.
[0037] The above shows and describes the basic principles and main features of the utility model and the advantages of the utility model. For those skilled in the art, it is obvious that the utility model is not limited to the details of the above exemplary embodiments, and can be implemented in other specific forms without departing from the spirit or basic features of the utility model. Therefore, no matter from which point of view, the embodiments should be regarded as exemplary and non-restrictive. The scope of the utility model is defined by the attached claims rather than the above description, and it is intended to include all changes within the meaning and scope of the equivalent elements of the claims. Any figure mark in the claims should not be regarded as limiting the claims involved.
[0038] In addition, it should be understood that although this specification is described in accordance with the implementation methods, not every implementation method contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should take the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other implementation methods that can be understood by those skilled in the art. The above content is only to illustrate the technical idea of the utility model, and cannot be used to limit the protection scope of the utility model. Any changes made on the basis of the technical solution in accordance with the technical idea proposed by the utility model shall fall within the protection scope of the claims of the utility model.
Claims
1. A full dry process system for recovering waste heat from converter flue gas, characterized in that: It comprises a converter (1), the flue gas outlet of the converter (1) is connected to the flue gas inlet of an adiabatic flue gas heat exchanger (2), the flue gas outlet of the adiabatic flue gas heat exchanger (2) is connected to the air inlet of a primary dust collector (3), the air outlet of the primary dust collector (3) is connected to the flue gas inlet of a low-temperature fine dust collector (6), the flue gas outlet of the low-temperature fine dust collector (6) is connected to one interface of a three-way switching valve (8), and the other two interfaces of the three-way switching valve (8) are respectively connected to a gas cabinet (9) and a gas dispersing self-combustion system (10); The gas cabinet (9) is used to deliver gas with qualified gas to gas users, and the gas dispersing self-combustion system (10) is used to burn and discharge gas with unqualified gas; The adiabatic flue gas heat exchanger (2) is provided with a deoxygenated water inlet (21) and a steam outlet (22); the deoxygenated water inlet (21) is connected to a deoxygenated water supply device; the steam outlet (22) is connected to an inlet end of a steam heat storage and flow stabilization device (15); and the outlet end of the steam heat storage and flow stabilization device (15) is connected to a steam pipe network (16).
2. A full dry process system for recovering waste heat from converter flue gas according to claim 1, characterized in that: The adiabatic flue gas heat exchanger (2) is provided with a coil, one end of the coil is connected to the deoxygenated water inlet (21), and the other end of the coil is connected to the steam outlet (22).
3. A full dry process system for converter flue gas waste heat recovery according to claim 2, characterized in that: A heat insulating protective layer (23) is provided on the heat insulating flue gas heat exchanger (2) outside the coil.
4. The all-dry process system for converter flue gas waste heat recovery according to claim 1, characterized in that: The gas outlet of the primary dust collector (3) is connected to the flue inlet of the explosion-proof heat pipe waste heat boiler (4), and the flue outlet of the explosion-proof heat pipe waste heat boiler (4) is connected to the flue gas inlet of the low-temperature fine dust collector (6); The explosion-proof heat pipe waste heat boiler (4) is provided with an inlet pipe (41) and a steam outlet pipe (42), wherein the inlet pipe (41) is connected to the deoxygenated water supply equipment, and the steam outlet pipe (42) is connected to the inlet end of the steam heat storage stabilizing flow device (15).
5. A full dry process system for converter flue gas waste heat recovery according to claim 4, characterized in that: The heat exchange tubes in the explosion-proof heat pipe waste heat boiler (4) are finned heat exchange tubes.
6. The all-dry process system for converter flue gas waste heat recovery according to claim 2, characterized in that: The dust content in the flue gas output by the low-temperature fine dust collector (6) is less than 10 mg / m 3 .
7. A full dry process system for converter flue gas waste heat recovery according to claim 6, characterized in that: The low-temperature fine dust collector (6) is an electric dust collector or a bag dust collector.
8. The all-dry process system for converter flue gas waste heat recovery according to claim 1, characterized in that: The primary dust collector (3) is connected to a dust recovery device (17).
9. A full dry process system for converter flue gas waste heat recovery according to claim 8, characterized in that: The primary dust collector (3) is a cyclone structure dust collector.
10. The all-dry process system for converter flue gas waste heat recovery according to claim 1, characterized in that: The steam heat storage and flow stabilizing device (15) is a steam heat accumulator.