Blast furnace hot blast stove exchange heat recycling system and recycling method thereof
By using the heat exchange of exhaust gas and pressure during the replacement of the blast furnace hot air furnace, the heat exchange was preheated, the problem of waste gas heat source waste, environmental pollution and noise hazards were solved, and efficient thermal use and environmental protection effect were achieved.
Patent Information
- Application Number
- CN202411799216.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-09
- Publication Date
- 2025-01-24
AI Technical Summary
During the process of replacing the blast furnace hot air furnace, the problems of waste gas heat source, environmental pollution and noise hazards have not been effectively solved.
A blast furnace hot blast furnace heat reuse system is designed. By utilizing the heat and pressure of the exhaust gas during the furnace exchange process, the gas and air are preheated by heat exchange to reduce exhaust gas emissions, and the exhaust gas flow rate is reduced by setting up spoilers. To improve heat exchange efficiency and noise reduction effect.
It effectively reduces the heat source waste and environmental pollution of the exhaust gas, reduces the harm to the human body caused by the noise during the exhaust gas emission process, increases the combustion temperature and coke ratio of the hot blast furnace, and improves the efficiency of blast furnace ironmaking.
Smart Images
Figure CN119351649A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of blast furnace production, and in particular to a blast furnace hot blast stove heat recycling system and a recycling method thereof. Background Art
[0002] Blast furnaces are generally equipped with three or four hot blast furnaces to provide hot air for the blast furnace. The working state of each hot blast furnace must go through four cycles of combustion-simmering-air supply-rest, and each hot blast furnace alternately supplies air to the blast furnace. Every time the hot blast furnace switches from the combustion state to the air supply state (i.e., furnace change), after the hot blast furnace that supplies air stops, the exhaust gas in the furnace (pressure is about 450kpa) must be heated and pressurized to another hot blast furnace; but generally it can only be pressurized to half (i.e., 225kpa), and the remaining exhaust gas with a pressure of about 225kpa will be directly discharged into the atmosphere through the chimney through the pressure relief valve; and according to the interval of hot blast furnace change, it basically needs to be discharged once every hour, so it causes a waste of heat source and also pollutes the environment. Therefore, the above problems need to be solved urgently. Summary of the invention
[0003] The technical problem to be solved by the present invention is to provide a blast furnace hot blast furnace heat recycling system and a recycling method thereof, which utilizes the heat and pressure of the exhaust gas in the furnace replacement process to preheat the coal gas and air through heat exchange, thereby reducing the waste of heat source of the exhaust gas, reducing the pollution of the exhaust gas to the atmosphere, and reducing the harm of the noise caused by the exhaust gas during the emission process to the human body.
[0004] In order to solve the above technical problems, the present invention adopts the following technical scheme: a blast furnace hot blast stove heat reuse system of the present invention comprises a chimney, a flue gas main, a 1# hot blast stove, a 2# hot blast stove, a 3# hot blast stove and a 4# hot blast stove; the 4# hot blast stove, the 3# hot blast stove, the 2# hot blast stove and the 1# hot blast stove are arranged in parallel from left to right in sequence, and the chimney is arranged vertically at intervals on the left side of the 4# hot blast stove; in the 4# hot blast stove, the 3# hot blast stove, the 2# hot blast stove and the 1# hot blast stove, the chimney is arranged vertically at intervals on the left side of the 4# hot blast stove; The two smoke exhaust ports of the furnace are also connected with a smoke branch pipe I and a smoke branch pipe II respectively, and each of the smoke branch pipes I is also connected with a hydraulic gate valve I for controlling its on-off, and each of the smoke branch pipes II is also connected with a hydraulic gate valve II for controlling its on-off; the other end of each of the smoke branch pipes I and the other end of each of the smoke branch pipes II are respectively connected with the smoke main pipe, and the smoke main pipe is connected with the chimney, so as to exhaust smoke when the furnace is burned; its innovative point is that it also includes an air preheater, Gas preheater, exhaust gas branch pipe, hydraulic gate valve III, exhaust gas main pipe and hydraulic gate valve IV; an exhaust gas branch pipe is provided on one side of each of the exhaust gas branch pipes I, and a hydraulic gate valve III for controlling its on and off is also provided on each of the exhaust gas branch pipes; one end of each of the exhaust gas branch pipes is respectively connected to the corresponding exhaust gas branch pipe I, and the other end thereof is respectively connected to the exhaust gas main pipe; an air preheater and a gas preheater are also arranged in parallel between the exhaust gas main pipe and the chimney, and the exhaust gas main pipe and the exhaust gas main pipe are connected to each other. The left end is connected with a channel inlet of the air preheater and a channel inlet of the gas preheater through pipelines, and a hydraulic gate valve IV for controlling the on-off thereof is also connected on the left end of the exhaust gas main pipe, and an outlet of a channel of the air preheater and an outlet of a channel of the gas preheater are connected with the chimney through pipelines, respectively, so that the air in the other channel of the air preheater and the gas in the other channel of the gas preheater are heat exchanged and preheated by the exhaust gas in the furnace changing process.
[0005] Preferably, the connection position between each of the exhaust gas branch pipes and the corresponding flue gas branch pipe I is located between each of the hydraulic gate valves I and the corresponding 1# hot blast stove, 2# hot blast stove, 3# hot blast stove or 4# hot blast stove.
[0006] Preferably, it also includes a hydraulic gate valve V and a hydraulic gate valve VII; a hydraulic gate valve V is also connected to the pipeline near the inlet of a channel of the air preheater, and the hydraulic gate valve V is used to control the connection between the air preheater and the flue gas main pipe and the exhaust gas main pipe; a hydraulic gate valve VII is also connected to the pipeline near the outlet of a channel of the air preheater, and the hydraulic gate valve VII is used to control the connection between the air preheater and the chimney.
[0007] Preferably, it also includes a hydraulic gate valve VI and a hydraulic gate valve VIII; a hydraulic gate valve VI is also connected to the pipeline near the inlet of a channel of the gas preheater, and the hydraulic gate valve VI is used to control the connection between the gas preheater and the flue gas main pipe and the exhaust gas main pipe; a hydraulic gate valve VIII is also connected to the pipeline near the outlet of a channel of the gas preheater, and the hydraulic gate valve VIII is used to control the connection between the gas preheater and the chimney.
[0008] Preferably, the air heat exchanger comprises a heat exchange box I, a heat exchange tube I, a fixed plate I, an air inlet pipe I and an air outlet pipe I; the heat exchange box I is a vertically arranged hollow rectangular parallelepiped structure, and a fixed plate I is also symmetrically arranged vertically and longitudinally inside the heat exchange box I, each of the fixed plates I is a rectangular structure matching the interior of the heat exchange box I, and is respectively fixedly connected to the front and rear inner walls of the heat exchange box I; inside the heat exchange box I, a plurality of heat exchange tubes I are horizontally spaced from top to bottom between the two fixed plates I, each of the heat exchange tubes I is a horizontally arranged hollow flat rectangular parallelepiped structure, and its left and right ends respectively extend vertically from the corresponding fixed plate I, and the adjacent ends of the two upper and lower adjacent heat exchange tubes I are respectively staggered. The heat exchanger tubes Ⅰ are sealed and connected, and are integrally formed to form a serpentine structure arranged vertically from top to bottom; the left end of the bottom heat exchange tube Ⅰ vertically extends to the left from the left side surface of the heat exchange box Ⅰ, and is sealed and connected with the input end of the hydraulic gate valve Ⅶ, and the right end of the top heat exchange tube Ⅰ extends horizontally to the right from the right side surface of the heat exchange box Ⅰ, and is sealed and connected with the output end of the hydraulic gate valve Ⅴ; an outlet pipe Ⅰ is provided on the right side of the lower surface of the heat exchange box Ⅰ, and the outlet pipe Ⅰ is connected with the interior of the heat exchange box Ⅰ; an intake pipe Ⅰ is provided on the left side of the upper surface of the heat exchange box Ⅰ, and the intake pipe Ⅰ is connected with the interior of the heat exchange box Ⅰ, so that air is introduced and preheated by heat exchange with the high-temperature exhaust gas introduced into the heat exchange tube Ⅰ.
[0009] Preferably, it also includes a spoiler block I; a plurality of spoiler blocks I are sequentially spaced along the length direction of each heat exchange tube I, each of the spoiler blocks I is horizontally and longitudinally arranged, and is a rectangular structure matching the interior of the corresponding heat exchange tube I; the height of each spoiler block I is two-thirds of the height of the interior of the corresponding heat exchange tube I, and adjacent spoiler blocks I are staggered and spaced up and down, and are respectively fixedly connected to the corresponding inner walls of the corresponding heat exchange tube I, thereby reducing the flow rate of the exhaust gas in the heat exchange tube I.
[0010] Preferably, the coal gas heat exchanger comprises a heat exchange box II, a heat exchange tube II, a fixed plate II, an air inlet pipe II and an air outlet pipe II; the heat exchange box II is a vertically arranged hollow rectangular parallelepiped structure, and a fixed plate II is also symmetrically arranged vertically and longitudinally inside the heat exchange box II, each of the fixed plates II is a rectangular structure matching the interior of the heat exchange box II, and is respectively fixedly connected to the front and rear inner walls of the heat exchange box II; a plurality of heat exchange tubes II are also horizontally spaced from top to bottom in the interior of the heat exchange box II relative to the two fixed plates II, each of the heat exchange tubes II is a horizontally arranged hollow flat rectangular parallelepiped structure, and its left and right ends respectively extend vertically from the corresponding fixed plate II, and the adjacent ends of the upper and lower adjacent heat exchange tubes II are respectively staggered. The heat exchanger boxes are sealed and connected, and are integrally formed to form a serpentine structure arranged vertically from top to bottom; the left end of the bottom heat exchange tube II vertically extends to the left from the left side surface of the heat exchange box II, and is sealed and connected with the input end of the hydraulic gate valve VIII, and the right end of the top heat exchange tube II horizontally extends to the right from the right side surface of the heat exchange box II, and is sealed and connected with the output end of the hydraulic gate valve VI; an outlet pipe II is provided on the right side of the lower surface of the heat exchange box II, and the outlet pipe II is connected with the interior of the heat exchange box II; an inlet pipe II is provided on the left side of the upper surface of the heat exchange box II, and the inlet pipe II is connected with the interior of the heat exchange box II, so that coal gas is introduced and heat exchange preheating is performed with the high-temperature exhaust gas introduced into the heat exchange tube II.
[0011] Preferably, it also includes a spoiler block II; a plurality of spoiler blocks II are sequentially spaced along the length direction of each heat exchange tube II, each spoiler block II is horizontally and longitudinally arranged, and is a rectangular structure matching the interior of the corresponding heat exchange tube II; the height of each spoiler block II is two-thirds of the height of the interior of the corresponding heat exchange tube II, and adjacent spoiler blocks II are staggered and spaced up and down, and are respectively fixedly connected to the corresponding inner walls of the corresponding heat exchange tube II, thereby reducing the flow rate of the exhaust gas in the heat exchange tube II.
[0012] The invention discloses a method for recycling heat from a blast furnace hot blast stove heat recycling system, the innovation of which is that it comprises the following steps: (1) First, set hydraulic gate valve V, hydraulic gate valve VI, hydraulic gate valve VII and hydraulic gate valve VIII to the open state, and set hydraulic gate valve I, hydraulic gate valve II, hydraulic gate valve III and hydraulic gate valve IV to the closed state; (2) When the 4# hot blast furnace has completed the air supply stage and is ready to enter the combustion stage, and the 3# hot blast furnace has completed the combustion stage and is ready to enter the air supply stage, first open the hydraulic gate valve III corresponding to the 3# hot blast furnace, and then open the hydraulic gate valve III corresponding to the 4# hot blast furnace. At this time, the exhaust gas in the 4# hot blast furnace is heat-balanced to the 3# hot blast furnace through the exhaust gas main pipe, and when the pressure reaches 245kpa, close the hydraulic gate valve III corresponding to the 3# hot blast furnace; (3) When the hydraulic gate valve III corresponding to the 3# hot blast furnace is completely closed, the hydraulic gate valve IV is opened. At this time, the exhaust gas with a residual pressure of 245 kPa in the 4# hot blast furnace flows into the heat exchange tube I and the heat exchange tube II through the exhaust gas main pipe, and is decelerated by the spoiler block I and the spoiler block II respectively, and the air in the heat exchange box I and the coal gas in the heat exchange box II are preheated by heat exchange respectively; (4) The waste gas cooled by heat exchange is discharged through the chimney; then when the hot air furnace needs to be replaced, the heat of the furnace exchange between the 3# hot air furnace and the 2# hot air furnace, between the 2# hot air furnace and the 1# hot air furnace, and between the 1# hot air furnace and the 4# hot air furnace is recycled according to the above steps, and the cycle is repeated.
[0013] Preferably, in the above step (3), the air is heated to 230-250°C by heat exchange after entering the air heat exchanger, and the coal gas is heated to 230-250°C by heat exchange after entering the coal gas heat exchanger, and then transported to the corresponding hot air furnace for combustion for use.
[0014] Beneficial effects of the present invention: (1) The present invention utilizes the heat and pressure of the exhaust gas during the furnace replacement process to preheat the coal gas and air through heat exchange, which not only reduces the waste of heat source of the exhaust gas, but also reduces the pollution of the exhaust gas to the atmosphere, and at the same time reduces the harm of the noise caused by the exhaust gas during the exhaust process to the human body; (2) The present invention can reduce the speed of the exhaust gas passing through the air preheater and the gas preheater by providing the spoiler block I and the spoiler block II, which not only improves the heat exchange efficiency but also has a silencing effect; (3) The present invention utilizes the residual waste gas to preheat the coal gas and air, thereby increasing the combustion calorific value of the coal gas and air, increasing the combustion temperature of the hot blast furnace, and reducing the coke ratio for blast furnace ironmaking. BRIEF DESCRIPTION OF THE DRAWINGS
[0015] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.
[0016] Figure 1 The present invention is a schematic structural diagram of a blast furnace hot blast stove heat reuse system.
[0017] Figure 2 for Figure 1 Schematic diagram of the structure of the air preheater part.
[0018] Figure 3 for Figure 1 Schematic diagram of the structure of the medium gas preheater part.
[0019] Among them, 1-1# hot blast stove; 2-2# hot blast stove; 3-3# hot blast stove; 4-4# hot blast stove; 5-air preheater; 6-gas preheater; 7-chimney; 8-flue gas branch pipe Ⅰ; 9-hydraulic gate valve Ⅰ; 10-flue gas branch pipe Ⅱ; 11-hydraulic gate valve Ⅱ; 12-flue gas main pipe; 13-waste gas branch pipe; 14-hydraulic gate valve Ⅲ; 15-waste gas main pipe; 16-hydraulic gate valve Ⅳ; 17-Hydraulic gate valve V; 18-Hydraulic gate valve VI; 19-Hydraulic gate valve VII; 20-Hydraulic gate valve VIII; 51-Heat exchange box I; 52-Heat exchange tube I; 53-Spoiler block I; 54-Fixed plate I; 55-Inlet pipe I; 56-Outlet pipe I; 61-Heat exchange box II; 62-Heat exchange tube II; 63-Spoiler block II; 64-Fixed plate II; 65-Inlet pipe II; 66-Outlet pipe II. DETAILED DESCRIPTION
[0020] The technical solution of the present invention will be clearly and completely described below through specific implementation methods.
[0021] A blast furnace hot blast furnace heat recycling system of the present invention comprises a chimney 7, a flue gas main pipe 12, a 1# hot blast furnace 1, a 2# hot blast furnace 2, a 3# hot blast furnace 3, a 4# hot blast furnace 4, an air preheater 5, a gas preheater 6, an exhaust gas branch pipe 13, a hydraulic gate valve III 14, an exhaust gas main pipe 15 and a hydraulic gate valve IV 16; the specific structure is as follows Figures 1 to 3 As shown, the 4# hot blast furnace 4, the 3# hot blast furnace 3, the 2# hot blast furnace 2 and the 1# hot blast furnace 1 are arranged in parallel from left to right in sequence, and the chimney 7 is arranged vertically at intervals on the left side of the 4# hot blast furnace 4; the two smoke exhaust ports of the 4# hot blast furnace 4, the 3# hot blast furnace 3, the 2# hot blast furnace 2 and the 1# hot blast furnace 1 are also connected with smoke branch pipes I8 and smoke branch pipes II10 respectively, and each smoke branch pipe I8 is also connected with a hydraulic gate valve I9 for controlling its on-off, and each smoke branch pipe II10 is also connected with a hydraulic gate valve II11 for controlling its on-off; the other end of each smoke branch pipe I8 and the other end of each smoke branch pipe II10 are respectively connected to the smoke main pipe 12, and the smoke main pipe 12 is connected to the chimney 7, so as to exhaust smoke when the furnace is burning.
[0022] The present invention provides a waste gas branch pipe 13 on one side of each flue gas branch pipe I8, and each waste gas branch pipe 13 is also connected to a hydraulic gate valve III 14 for controlling the on-off thereof; Figures 1 to 3 As shown, one end of each exhaust gas branch pipe 13 is respectively connected to the corresponding flue gas branch pipe Ⅰ8, and the other end thereof is respectively connected to the exhaust gas main pipe 15; the connection position of each exhaust gas branch pipe 13 and the corresponding flue gas branch pipe Ⅰ8 is located at the section between each hydraulic gate valve Ⅰ9 and the corresponding 1# hot blast furnace 1, 2# hot blast furnace 2, 3# hot blast furnace 3 or 4# hot blast furnace 4.
[0023] like Figures 1 to 3 As shown, an air preheater 5 and a gas preheater 6 are arranged in parallel between the flue gas main pipe 12 and the chimney 7, and the left ends of the flue gas main pipe 12 and the exhaust gas main pipe 15 are respectively connected with a channel inlet of the air preheater 5 and a channel inlet of the gas preheater 6 through pipelines, and a hydraulic gate valve IV16 for controlling the on-off of the exhaust gas main pipe 15 is also connected at its left end, and an outlet of one channel of the air preheater 5 and an outlet of one channel of the gas preheater 6 are respectively connected with the chimney 7 through pipelines, so that the air in the other channel of the air preheater 5 and the gas in the other channel of the gas preheater 6 are heat exchanged and preheated by the exhaust gas in the furnace changing process.
[0024] like Figures 1 to 3 As shown, a hydraulic gate valve V17 is also connected to the pipeline near the inlet of a channel of the air preheater 5, and the hydraulic gate valve V17 is used to control the connection between the air preheater 5 and the flue gas main pipe 12 and the exhaust gas main pipe 15; a hydraulic gate valve VII19 is also connected to the pipeline near the outlet of a channel of the air preheater 5, and the connection between the air preheater 5 and the chimney 7 is controlled by the hydraulic gate valve VII19.
[0025] like Figures 1 to 3 As shown, a hydraulic gate valve VI18 is also connected to the pipeline at the inlet of a channel near the gas preheater 6, and the hydraulic gate valve VI18 is used to control the connection between the gas preheater 6 and the flue gas main pipe 12 and the exhaust gas main pipe 15; a hydraulic gate valve VIII20 is also connected to the pipeline at the outlet of a channel near the gas preheater 6, and the connection between the gas preheater 6 and the chimney 7 is controlled by the hydraulic gate valve VIII20.
[0026] The air heat exchanger of the present invention comprises a heat exchange box Ⅰ51, a heat exchange tube Ⅰ52, a spoiler block Ⅰ53, a fixing plate Ⅰ54, an air inlet pipe Ⅰ55 and an air outlet pipe Ⅰ56; Figure 1 , Figure 2As shown, the heat exchange box Ⅰ51 is a vertically arranged hollow rectangular parallelepiped structure, and a fixed plate Ⅰ54 is symmetrically arranged vertically and longitudinally inside it. Each fixed plate Ⅰ54 is a rectangular structure matching the interior of the heat exchange box Ⅰ51, and is fixedly connected to the front and rear inner walls of the heat exchange box Ⅰ51 respectively; inside the heat exchange box Ⅰ51, a number of heat exchange tubes Ⅰ52 are horizontally spaced from top to bottom between the two fixed plates Ⅰ54. Each heat exchange tube Ⅰ52 is a horizontally arranged hollow flat rectangular parallelepiped structure, and the left and right ends thereof respectively extend vertically from the corresponding fixed plates Ⅰ54, and the adjacent ends of the upper and lower adjacent heat exchange tubes Ⅰ52 are respectively staggered and sealed and connected, and are integrally formed to form a A serpentine structure arranged vertically from top to bottom; the left end of the lowest heat exchange tube Ⅰ52 extends vertically to the left out of the left side surface of the heat exchange box Ⅰ51, and is sealed and connected with the input end of the hydraulic gate valve Ⅶ19, and the right end of the uppermost heat exchange tube Ⅰ52 extends horizontally to the right out of the right side surface of the heat exchange box Ⅰ51, and is sealed and connected with the output end of the hydraulic gate valve Ⅴ17; an outlet pipe Ⅰ56 is provided on the right side of the lower surface of the heat exchange box Ⅰ51, and the outlet pipe Ⅰ56 is connected with the interior of the heat exchange box Ⅰ51; an intake pipe Ⅰ55 is provided on the left side of the upper surface of the heat exchange box Ⅰ51, and the intake pipe Ⅰ55 is connected with the interior of the heat exchange box Ⅰ51, and air is introduced into the air, and heat exchange preheating is performed with the high-temperature exhaust gas introduced into the heat exchange tube Ⅰ52.
[0027] like Figure 1 , Figure 2 As shown, inside each heat exchange tube Ⅰ52, a number of spoiler blocks Ⅰ53 are sequentially arranged along its length direction. Each spoiler block Ⅰ53 is arranged horizontally and longitudinally, and is a rectangular structure that matches the inside of the corresponding heat exchange tube Ⅰ52. The height of each spoiler block Ⅰ53 is two-thirds of the height of the inside of the corresponding heat exchange tube Ⅰ52, and adjacent spoiler blocks Ⅰ53 are staggered and arranged at intervals up and down, and are respectively fixedly connected to the corresponding inner walls of the corresponding heat exchange tube Ⅰ52, thereby reducing the flow rate of the exhaust gas in the heat exchange tube Ⅰ52.
[0028] The gas heat exchanger of the present invention comprises a heat exchange box II 61, a heat exchange tube II 62, a spoiler block II 63, a fixing plate II 64, an air inlet pipe II 65 and an air outlet pipe II 66; Figure 1 , Figure 3As shown, the heat exchange box II 61 is a hollow rectangular parallelepiped structure arranged vertically, and a fixed plate II 64 is arranged vertically and longitudinally symmetrically inside the heat exchange box II 61. Each fixed plate II 64 is a rectangular structure matching the inside of the heat exchange box II 61, and is fixedly connected to the front and rear inner walls of the heat exchange box II 61 respectively; a plurality of heat exchange tubes II 62 are arranged horizontally and spaced from top to bottom between the two fixed plates II 64 inside the heat exchange box II 61. Each heat exchange tube II 62 is a hollow flat rectangular parallelepiped structure arranged horizontally and transversely, and the corresponding fixed plates II 64 are vertically extended from the left and right ends thereof respectively, and the adjacent ends of the upper and lower adjacent heat exchange tubes II 62 are staggered and sealed and connected, and are integrally formed to form a A serpentine structure is arranged vertically from top to bottom; the left end of the bottom heat exchange tube Ⅱ62 extends vertically to the left out of the left side surface of the heat exchange box Ⅱ61, and is sealed and connected with the input end of the hydraulic gate valve Ⅷ20, and the right end of the top heat exchange tube Ⅱ62 extends horizontally to the right out of the right side surface of the heat exchange box Ⅱ61, and is sealed and connected with the output end of the hydraulic gate valve Ⅵ18; an outlet pipe Ⅱ66 is provided on the right side of the lower surface of the heat exchange box Ⅱ61, and the outlet pipe Ⅱ66 is connected with the interior of the heat exchange box Ⅱ61; an intake pipe Ⅱ65 is provided on the left side of the upper surface of the heat exchange box Ⅱ61, and the intake pipe Ⅱ65 is connected with the interior of the heat exchange box Ⅱ61, and then the coal gas is introduced, and heat exchange preheating is performed with the high-temperature exhaust gas introduced into the heat exchange tube Ⅱ62.
[0029] like Figure 1 , Figure 3 As shown, a number of spoiler blocks II 63 are sequentially arranged inside each heat exchange tube II 62 along its length direction, and each spoiler block II 63 is arranged horizontally and longitudinally, and is a rectangular structure matching the inside of the corresponding heat exchange tube II 62; the height of each spoiler block II 63 is two-thirds of the height of the inside of the corresponding heat exchange tube II 62, and adjacent spoiler blocks II 63 are arranged at intervals with an offset up and down, and are respectively fixedly connected to the corresponding inner walls of the corresponding heat exchange tube II 62, thereby reducing the flow rate of the exhaust gas in the heat exchange tube II 62.
[0030] A method for recycling heat from a blast furnace hot blast stove heat recycling system of the present invention is as follows: Figures 1 to 3 As shown, the following steps are included: (1) First, hydraulic gate valve V17, hydraulic gate valve VI18, hydraulic gate valve VII19 and hydraulic gate valve VIII20 are set to the open state, and hydraulic gate valve I9, hydraulic gate valve II11, hydraulic gate valve III14 and hydraulic gate valve IV16 are set to the closed state.
[0031] (2) When the 4# hot blast furnace 4 completes the air supply stage and is ready to enter the combustion stage, and the 3# hot blast furnace 3 completes the combustion stage and is ready to enter the air supply stage, the exhaust gas pressure in the 4# hot blast furnace 4 is too high and is pressurized on one side, resulting in the corresponding hydraulic gate valve Ⅰ9 and hydraulic gate valve Ⅱ11 being unable to open. Therefore, the hydraulic gate valve Ⅲ14 corresponding to the 3# hot blast furnace 3 is opened first, and then the hydraulic gate valve Ⅲ14 corresponding to the 4# hot blast furnace 4 is opened. At this time, the exhaust gas in the 4# hot blast furnace 4 is heat-balanced through the exhaust gas main pipe 15 to the 3# hot blast furnace 3, and when the pressure reaches 245kpa, the hydraulic gate valve Ⅲ14 corresponding to the 3# hot blast furnace 3 is closed.
[0032] (3) When the hydraulic gate valve III 14 corresponding to the 3# hot blast furnace 3 is completely closed, the hydraulic gate valve IV 16 is opened. At this time, the exhaust gas with a residual pressure of 245 kPa in the 4# hot blast furnace 4 flows into the heat exchange tube I 52 and the heat exchange tube II 62 through the exhaust gas main pipe 15, and is decelerated by the spoiler block I 53 and the spoiler block II 63, and the air in the heat exchange box I 51 and the coal gas in the heat exchange box II 61 are preheated by heat exchange.
[0033] In the above steps, air enters the air heat exchanger and is heated to 230-250°C through heat exchange, and coal gas enters the coal gas heat exchanger and is heated to 230-250°C through heat exchange, and then is transported to the corresponding hot blast furnace for combustion.
[0034] (4) The exhaust gas cooled by heat exchange is discharged through the chimney 7; then, when the hot blast furnace needs to be replaced, the heat of the furnace exchange between the 3# hot blast furnace 3 and the 2# hot blast furnace 2, between the 2# hot blast furnace 2 and the 1# hot blast furnace 1, and between the 1# hot blast furnace 1 and the 4# hot blast furnace 4 is recycled according to the above steps, and the cycle is repeated.
[0035] When the furnace is fired, the hydraulic gate valve I9 and the hydraulic gate valve II11 of the corresponding combustion furnace can be opened, and then the air in the air preheater 5 and the gas in the gas preheater 6 are heat exchanged and preheated through the flue main pipe, and then the smoke is exhausted through the chimney 7. Beneficial effects of the present invention: (1) The present invention utilizes the heat and pressure of the exhaust gas during the furnace replacement process to preheat the coal gas and air through heat exchange, which not only reduces the waste of heat source of the exhaust gas, but also reduces the pollution of the exhaust gas to the atmosphere, and at the same time reduces the harm of the noise caused by the exhaust gas during the exhaust process to the human body; (2) The present invention can reduce the speed of the exhaust gas passing through the air preheater 5 and the gas preheater 6 by providing the spoiler block I 53 and the spoiler block II 63, which not only improves the heat exchange efficiency but also has a silencing effect; (3) The present invention utilizes the residual waste gas to preheat the coal gas and air, thereby increasing the combustion calorific value of the coal gas and air, increasing the combustion temperature of the hot blast furnace, and reducing the coke ratio for blast furnace ironmaking.
[0036] The embodiments described above are merely descriptions of preferred implementation modes of the present invention, and are not intended to limit the concept and scope of the present invention. Without departing from the design concept of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary engineering technicians in the field should fall within the protection scope of the present invention. The technical contents for which protection is sought in the present invention have been fully recorded in the technical requirements.
Claims
1. A blast furnace hot blast stove heat reuse system, comprising a chimney, a flue gas main, a 1# hot blast stove, a 2# hot blast stove, a 3# hot blast stove and a 4# hot blast stove; the 4# hot blast stove, the 3# hot blast stove, the 2# hot blast stove and the 1# hot blast stove are arranged in parallel from left to right in sequence, and the chimney is arranged vertically at intervals on the left side of the 4# hot blast stove; the two smoke exhaust ports of the 4# hot blast stove, the 3# hot blast stove, the 2# hot blast stove and the 1# hot blast stove are also connected with a flue gas branch pipe I and a flue gas branch pipe II respectively, and each of the flue gas branch pipes I is also connected with a hydraulic gate valve I for controlling its on-off, and each of the flue gas branch pipes II is also connected with a hydraulic gate valve II for controlling its on-off; the other end of each of the flue gas branch pipes I and the other end of each of the flue gas branch pipes II are respectively connected with the flue gas main, and the flue gas main is connected with the chimney, so as to exhaust smoke when the furnace is burned; characterized in that: It also includes an air preheater, a gas preheater, an exhaust gas branch pipe, a hydraulic gate valve III, an exhaust gas main pipe and a hydraulic gate valve IV; an exhaust gas branch pipe is provided on one side of each of the flue gas branch pipes I, and a hydraulic gate valve III for controlling the on-off of each of the exhaust gas branch pipes is also provided; one end of each of the exhaust gas branch pipes is respectively connected to the corresponding flue gas branch pipe I, and the other end thereof is respectively connected to the exhaust gas main pipe; an air preheater and a gas preheater are also arranged in parallel between the flue gas main pipe and the chimney, and the flue gas main pipe and The left end of the exhaust gas main pipe is connected with a channel inlet of the air preheater and a channel inlet of the gas preheater through pipelines, and a hydraulic gate valve IV for controlling the on-off thereof is also connected on the exhaust gas main pipe near its left end, and a channel outlet of the air preheater and a channel outlet of the gas preheater are connected with the chimney through pipelines, respectively, so that the air in the other channel of the air preheater and the gas in the other channel of the gas preheater are heat exchanged and preheated by the exhaust gas in the furnace changing process.
2. A blast furnace hot blast stove heat recycling system according to claim 1, characterized in that: The connection position between each exhaust gas branch pipe and the corresponding flue gas branch pipe I is located between each hydraulic gate valve I and the corresponding 1# hot blast stove, 2# hot blast stove, 3# hot blast stove or 4# hot blast stove.
3. A blast furnace hot blast stove heat recycling system according to claim 2, characterized in that: It also includes a hydraulic gate valve V and a hydraulic gate valve VII; a hydraulic gate valve V is also connected to the pipeline near the inlet of a channel of the air preheater, and the hydraulic gate valve V is used to control the connection between the air preheater and the flue gas main pipe and the exhaust gas main pipe; a hydraulic gate valve VII is also connected to the pipeline near the outlet of a channel of the air preheater, and the hydraulic gate valve VII is used to control the connection between the air preheater and the chimney.
4. A blast furnace hot blast stove heat recycling system according to claim 3, characterized in that: It also includes a hydraulic gate valve VI and a hydraulic gate valve VIII; a hydraulic gate valve VI is also connected to the pipeline near the inlet of a channel of the gas preheater, and the hydraulic gate valve VI is used to control the connection between the gas preheater and the flue gas main pipe and the exhaust gas main pipe; a hydraulic gate valve VIII is also connected to the pipeline near the outlet of a channel of the gas preheater, and the hydraulic gate valve VIII is used to control the connection between the gas preheater and the chimney.
5. A blast furnace hot blast stove heat recycling system according to claim 4, characterized in that: The air heat exchanger comprises a heat exchange box I, a heat exchange tube I, a fixed plate I, an air inlet pipe I and an air outlet pipe I; the heat exchange box I is a vertically arranged hollow rectangular parallelepiped structure, and a fixed plate I is also symmetrically arranged vertically and longitudinally inside the heat exchange box I, each of the fixed plates I is a rectangular structure matching the interior of the heat exchange box I, and is respectively fixedly connected to the front and rear inner walls of the heat exchange box I; a plurality of heat exchange tubes I are horizontally spaced from top to bottom in the interior of the heat exchange box I relative to the two fixed plates I, each of the heat exchange tubes I is a horizontally arranged hollow flat rectangular parallelepiped structure, and its left and right ends respectively extend vertically from the corresponding fixed plate I, and the adjacent ends of the two upper and lower adjacent heat exchange tubes I are respectively staggered and sealed. The heat exchanger tubes Ⅰ are connected and integrally formed to form a serpentine structure arranged vertically from top to bottom; the left end of the bottom heat exchange tube Ⅰ vertically extends to the left from the left side surface of the heat exchange box Ⅰ, and is sealed and connected with the input end of the hydraulic gate valve Ⅶ; the right end of the top heat exchange tube Ⅰ horizontally extends to the right from the right side surface of the heat exchange box Ⅰ, and is sealed and connected with the output end of the hydraulic gate valve Ⅴ; an outlet pipe Ⅰ is provided on the right side of the lower surface of the heat exchange box Ⅰ, and the outlet pipe Ⅰ is connected with the interior of the heat exchange box Ⅰ; an intake pipe Ⅰ is provided on the left side of the upper surface of the heat exchange box Ⅰ, and the intake pipe Ⅰ is connected with the interior of the heat exchange box Ⅰ, so that air is introduced and preheated by heat exchange with the high-temperature exhaust gas introduced into the heat exchange tube Ⅰ.
6. A blast furnace hot blast stove heat recycling system according to claim 5, characterized in that: It also includes a spoiler block I; a plurality of spoiler blocks I are sequentially spaced along the length direction of each heat exchange tube I, each of the spoiler blocks I is horizontally and longitudinally arranged, and is a rectangular structure matching the interior of the corresponding heat exchange tube I; the height of each spoiler block I is two-thirds of the height of the interior of the corresponding heat exchange tube I, and adjacent spoiler blocks I are staggered and spaced up and down, and are respectively fixedly connected to the corresponding inner walls of the corresponding heat exchange tube I, thereby reducing the flow rate of the exhaust gas in the heat exchange tube I.
7. A blast furnace hot blast stove heat recycling system according to claim 4, characterized in that: The coal gas heat exchanger comprises a heat exchange box II, a heat exchange tube II, a fixed plate II, an air inlet pipe II and an air outlet pipe II; the heat exchange box II is a vertically arranged hollow rectangular parallelepiped structure, and a fixed plate II is also symmetrically arranged vertically and longitudinally inside the heat exchange box II, each of the fixed plates II is a rectangular structure matching the inside of the heat exchange box II, and is respectively fixedly connected to the front and rear inner walls of the heat exchange box II; a plurality of heat exchange tubes II are horizontally spaced from top to bottom in the inside of the heat exchange box II relative to the two fixed plates II, each of the heat exchange tubes II is a horizontally arranged hollow flat rectangular parallelepiped structure, and the left and right ends thereof respectively extend vertically from the corresponding fixed plate II, and the adjacent ends of the upper and lower adjacent heat exchange tubes II are respectively staggered and sealed. The heat exchanger boxes are connected and integrally formed to form a serpentine structure arranged vertically from top to bottom; the left end of the bottom heat exchange tube II vertically extends to the left from the left side surface of the heat exchange box II and is sealed and connected with the input end of the hydraulic gate valve VIII, and the right end of the top heat exchange tube II horizontally extends to the right from the right side surface of the heat exchange box II and is sealed and connected with the output end of the hydraulic gate valve VI; an outlet pipe II is provided on the right side of the lower surface of the heat exchange box II, and the outlet pipe II is connected with the interior of the heat exchange box II; an inlet pipe II is provided on the left side of the upper surface of the heat exchange box II, and the inlet pipe II is connected with the interior of the heat exchange box II, so that coal gas is introduced and heat exchange preheating is performed with the high-temperature exhaust gas introduced into the heat exchange tube II.
8. A blast furnace hot blast stove heat recycling system according to claim 7, characterized in that: It also includes a spoiler block II; a plurality of spoiler blocks II are sequentially arranged along the length direction of each heat exchange tube II, each spoiler block II is arranged horizontally and longitudinally, and is a rectangular structure matching the interior of the corresponding heat exchange tube II; the height of each spoiler block II is two-thirds of the height of the interior of the corresponding heat exchange tube II, and adjacent spoiler blocks II are arranged at intervals in an upper and lower staggered manner, and are respectively fixedly connected to the corresponding inner walls of the corresponding heat exchange tube II, thereby reducing the flow rate of the exhaust gas in the heat exchange tube II.
9. A method for recycling heat from a blast furnace hot blast stove heat recycling system according to any one of claims 1 to 8, characterized in that The following steps are involved: (1) First, set hydraulic gate valve V, hydraulic gate valve VI, hydraulic gate valve VII and hydraulic gate valve VIII to the open state, and set hydraulic gate valve I, hydraulic gate valve II, hydraulic gate valve III and hydraulic gate valve IV to the closed state; (2) When the 4# hot blast furnace has completed the air supply stage and is ready to enter the combustion stage, and the 3# hot blast furnace has completed the combustion stage and is ready to enter the air supply stage, first open the hydraulic gate valve III corresponding to the 3# hot blast furnace, and then open the hydraulic gate valve III corresponding to the 4# hot blast furnace. At this time, the exhaust gas in the 4# hot blast furnace is heat-balanced to the 3# hot blast furnace through the exhaust gas main pipe, and when the pressure reaches 245kpa, close the hydraulic gate valve III corresponding to the 3# hot blast furnace; (3) When the hydraulic gate valve III corresponding to the 3# hot blast furnace is completely closed, the hydraulic gate valve IV is opened. At this time, the exhaust gas with a residual pressure of 245 kPa in the 4# hot blast furnace flows into the heat exchange tube I and the heat exchange tube II through the exhaust gas main pipe, and is decelerated by the spoiler block I and the spoiler block II respectively, and the air in the heat exchange box I and the coal gas in the heat exchange box II are preheated by heat exchange respectively; (4) The waste gas cooled by heat exchange is discharged through the chimney; then when the hot air furnace needs to be replaced, the heat of the furnace exchange between the 3# hot air furnace and the 2# hot air furnace, between the 2# hot air furnace and the 1# hot air furnace, and between the 1# hot air furnace and the 4# hot air furnace is recycled according to the above steps, and the cycle is repeated.
10. The method for recycling heat from a blast furnace hot blast stove heat recycling system according to claim 9, characterized in that: In the above step (3), the air enters the air heat exchanger and is heated to 230-250°C by heat exchange, and the coal gas enters the coal gas heat exchanger and is heated to 230-250°C by heat exchange, and then is transported to the corresponding hot air furnace for combustion.