Continuous waste heat utilization aluminum alloy annealing furnace

Abstract

The invention belongs to the technical field of metal heat treatment, and discloses a continuous waste heat utilization aluminum alloy annealing furnace. The continuous waste heat utilization aluminum alloy annealing furnace comprises a feeding table, the left side of the feeding table is fixedly connected with a front heat exchange door, the left side of the front heat exchange door is fixedly connected with a front heat exchange chamber, the left side of the front heat exchange chamber is fixedly connected with a front transition chamber door, and the left side of the front transition chamber door is fixedly connected with a front transition chamber; and the left side of the front transition chamber is fixedly connected with a tail gas pre-heating door. According to the continuous type waste heat utilization aluminum alloy annealing furnace, the structure is adopted, heat of an annealed workpiece can be used for waste heat removal of an unannealed workpiece for cold and heat exchange, aluminum alloy is further heated through the smoke heat recovery system, waste heat is utilized, the high automation level and low energy consumption are maintained, and meanwhile the annealing heat treatment cost is further reduced.

Description

Technical Field

[0001] The invention relates to the technical field of metal heat treatment, in particular to a continuous waste heat utilization aluminum alloy annealing furnace. Background Art

[0002] Annealing furnace is a kind of equipment used for metal annealing. Annealing is a process of heating metal to a certain temperature and keeping it for a period of time, and then slowly cooling it. This process can improve the internal structure of the metal, increase its plasticity, reduce hardness, eliminate internal stress, and make it more suitable for subsequent processing or use.

[0003] The current aluminum alloy annealing furnace structure is divided into two types: periodic and continuous. Periodic annealing uses trolley furnaces, bell furnaces, etc., which have high annealing energy consumption and unstable quality. Continuous annealing furnaces mostly use pusher type, which has stable quality but cannot effectively utilize the waste heat of the workpiece. Therefore, whether it is a traditional periodic furnace or a pusher type continuous furnace, it is impossible to utilize the waste heat of the workpiece, and it is difficult to further significantly reduce the cost of annealing production. Summary of the invention

[0004] The purpose of the present invention is to provide a continuous waste heat utilization aluminum alloy annealing furnace, which mainly adopts front and rear heat convection exchange technology and a high-temperature fire-blocking door mechanism to achieve a new furnace structure for heat exchange between cold and hot workpieces.

[0005] To achieve the above objectives, the present invention is implemented through the following technical solutions: A continuous waste heat utilization aluminum alloy annealing furnace, comprising a loading platform, a front heat exchange door is fixedly connected to the left side of the loading platform, a front heat exchange chamber is fixedly connected to the left side of the front heat exchange door, a front transition chamber door is fixedly connected to the left side of the front heat exchange chamber, a front transition chamber is fixedly connected to the left side of the front transition chamber door, and an exhaust gas preheating heater is fixedly connected to the left side of the front transition chamber;

[0006] The left side of the exhaust gas preheating heater is fixedly connected to an exhaust gas preheating chamber, the exhaust gas preheating chamber is fixedly connected to a plurality of heat exchange fans, and the left side of the exhaust gas preheating chamber is fixedly connected to a front insulation door;

[0007] The left side of the front insulation door is fixedly connected with a main heating furnace, the main heating furnace is fixedly connected with a furnace body circulation fan, a thermocouple is fixedly connected in the main heating furnace, a gas burner is fixedly connected in the main heating furnace, and a flue gas heat recovery system is also arranged in the main heating furnace, the absorption end of the flue gas heat recovery system is located in the main heating furnace, the discharge end of the flue gas heat recovery system is located in the tail gas preheating chamber, and the absorption end and the discharge end of the flue gas heat recovery system are connected through a pipeline;

[0008] The left side of the main heating furnace is fixedly connected with a rear insulation door, the left side of the rear insulation door is fixedly connected with a rear transition chamber, and the left side of the rear transition chamber is fixedly connected with a rear transition chamber door;

[0009] The left side of the rear transition chamber door is fixedly connected to the rear heat exchange chamber, the left side of the rear heat exchange chamber is fixedly connected to the rear heat exchange chamber door, the left side of the rear heat exchange chamber door is fixedly connected to the discharge platform, and a furnace gas heat exchange system is arranged in the rear heat exchange chamber.

[0010] Preferably, one end of a transmission rod is connected to the loading platform through a driving member, and the other end of the transmission rod extends leftward to the position of the unloading platform.

[0011] Preferably, the rear heat exchange chamber is connected to the front heat exchange chamber via a double-branch pipeline.

[0012] Preferably, the furnace gas heat exchange system is also arranged in the front heat exchange chamber.

[0013] Preferably, the furnace body circulation fan is arranged in each heating zone of the heating main furnace.

[0014] Preferably, the front insulation door and the rear insulation door are both used to insulate the heat in the main heating furnace.

[0015] By adopting the above technical solution, the beneficial effects of the present invention are:

[0016] 1. The continuous waste heat utilization aluminum alloy annealing furnace adopts the above structure, and can use the heat of the workpiece after annealing to remove the waste heat of the unannealed workpiece (cold material) for heat exchange. The flue gas heat recovery system further heats the aluminum alloy and utilizes the waste heat, which maintains a high level of automation and low energy consumption while further reducing the cost of annealing heat treatment.

[0017] 2. The continuous waste heat utilization aluminum alloy annealing furnace currently consumes about 22M3 natural gas per ton of annealing energy. The double-layer heat exchange technology can reduce the energy consumption to 15M3 natural gas per ton, so the production cost can be significantly reduced. At the same time, the furnace adopts a roller bottom structure, combined with photoelectric switches and electrical programs, etc., which can make the entire production and waste heat utilization links fully automated, further reducing labor intensity. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0019] Figure 2 It is a schematic diagram of the top structure of the present invention.

[0020] In the figure: 1. loading platform; 2. front heat exchange door; 3. front heat exchange chamber; 4. front transition chamber door; 5. front transition chamber; 6. exhaust gas preheating door; 7. heat exchange fan; 8. exhaust gas preheating chamber; 9. front insulation door; 10. furnace body circulation fan; 11. heating main furnace; 12. thermocouple; 13. rear insulation door; 14. rear transition chamber; 15. rear transition chamber door; 16. rear heat exchange chamber; 17. rear heat exchange chamber door; 18. unloading platform; 19. furnace gas heat exchange system; 20. transmission rod; 21. gas burner; 22. flue gas heat recovery system. DETAILED DESCRIPTION

[0021] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0022] See also Figure 1-2 The present invention provides a technical solution: a continuous waste heat utilization aluminum alloy annealing furnace, comprising a loading platform 1, a front heat exchange door 2 is fixedly connected to the left side of the loading platform 1, a front heat exchange chamber 3 is fixedly connected to the left side of the front heat exchange door 2, a front transition chamber door 4 is fixedly connected to the left side of the front heat exchange chamber 3, a front transition chamber 5 is fixedly connected to the left side of the front transition chamber door 4, and an exhaust gas preheating heater 6 is fixedly connected to the left side of the front transition chamber 5;

[0023] The left side of the exhaust gas preheating heater 6 is fixedly connected to an exhaust gas preheating chamber 8, a plurality of heat exchange fans 7 are fixedly connected to the exhaust gas preheating chamber 8, and the left side of the exhaust gas preheating chamber 8 is fixedly connected to a front insulation door 9;

[0024] A heating main furnace 11 is fixedly connected to the left side of the front insulation door 9, a furnace body circulation fan 10 is fixedly connected to the heating main furnace 11, a thermocouple 12 is fixedly connected in the heating main furnace 11, a gas burner 21 is fixedly connected in the heating main furnace 11, and a flue gas heat recovery system 22 is also arranged in the heating main furnace 11, an absorption end of the flue gas heat recovery system 22 is located in the heating main furnace 11, and an exhaust end of the flue gas heat recovery system 22 is located in the tail gas preheating chamber 8, and the absorption end and the exhaust end of the flue gas heat recovery system 22 are connected through a pipeline;

[0025] A rear heat insulation door 13 is fixedly connected to the left side of the main heating furnace 11, a rear transition chamber 14 is fixedly connected to the left side of the rear heat insulation door 13, and a rear transition chamber door 15 is fixedly connected to the left side of the rear transition chamber 14;

[0026] The left side of the rear transition chamber door 15 is fixedly connected to the rear heat exchange chamber 16, the left side of the rear heat exchange chamber 16 is fixedly connected to the rear heat exchange chamber door 17, the left side of the rear heat exchange chamber door 17 is fixedly connected to the discharge platform 18, and the rear heat exchange chamber 16 is provided with a furnace gas heat exchange system 19.

[0027] One end of a transmission rod 20 is connected to the loading platform 1 through a driving member, and the other end of the transmission rod 20 extends leftward to the position of the unloading platform 18.

[0028] The loading platform 1, the front heat exchange chamber 3, the front transition chamber 5, the exhaust gas preheating chamber 8, the main heating furnace 11, the rear transition chamber 14, the rear heat exchange chamber 16 and the unloading platform 18 are all provided with rollers to carry and transport the workpiece basket. The driving component is a motor conventionally used in conveyor belts.

[0029] The rear heat exchange chamber 16 is connected to the front heat exchange chamber 3 through a double-branch pipeline.

[0030] The furnace gas heat exchange system 19 is also arranged in the front heat exchange chamber 3.

[0031] The furnace gas heat exchange system 19 is respectively arranged in the front heat exchange chamber 3 and the rear heat exchange chamber 16.

[0032] Among them, during the cooling process of the high-temperature aluminum alloy in the rear heat exchange chamber 16, the furnace gas heat exchange system 19 is used to transport heat to the front heat exchange chamber 3 to heat the untreated cold material. The furnace gas heat exchange system 19 in the front heat exchange chamber 3 transports the cold furnace gas to the rear heat exchange chamber 16 to cool the aluminum alloy, thereby realizing heat and cold exchange and utilizing waste heat.

[0033] The furnace circulation fan 10 is arranged in each heating zone of the heating main furnace 11 .

[0034] The front insulating door 9 and the rear insulating door 13 are both used to insulate the heat in the main furnace 11 .

[0035] The front insulating door 9 prevents the heat of the main furnace 11 from being transmitted to the exhaust preheating chamber 8 , and the rear insulating door 13 prevents the heat of the main furnace 11 from being escaped to the rear transition chamber door 15 .

[0036] The working principle adopted by this application is:

[0037] The treated hot material slowly moves toward the discharge direction in the rear heat exchange chamber 16, and the untreated cold material in the front heat exchange chamber 3 slowly moves toward the heating zone, through two sets of furnace gas heat exchange systems 19, one set is installed in the rear heat exchange chamber 16, and heat is transported to the front heat exchange chamber 3 to heat the untreated cold material, and the other set is installed in the front heat exchange chamber 3, and cold furnace gas is transported to the rear heat exchange chamber 16 to cool the aluminum alloy, realizing cold and heat exchange and waste heat utilization. The heat exchange is maintained for a long time until the heating starts, ensuring the final effect of the waste heat exchange.

[0038] When the continuous waste heat utilization aluminum alloy annealing furnace is working, the operator uses a crane or an electric hoist to lift the material to be heat treated to the loading platform 1. When the photoelectric switch in the loading platform 1 senses that there is material, the front heat exchange door 2 is opened through the PLC program control, and the unheat treated material quickly enters the front heat exchange chamber 3. At this time, the front heat exchange door 2 is closed, and the unheat treated material moves forward according to the feeding rhythm. When the untreated material approaches the front transition chamber 5 and triggers the photoelectric switch, the front transition chamber door 4 is opened, and the unheat treated material quickly enters the front transition chamber 5. When the current batch of unheat treated materials enters the front transition chamber 5, the front heat exchange door 2 is opened again, and the next batch of unheat treated materials quickly enters the front heat exchange chamber 3 and repeats the above operation;

[0039] After the previous batch of unheat-treated materials enters the front transition chamber 5 and undergoes a process cycle, the tail gas preheating heater 6 is opened, and the unheat-treated materials quickly enter the tail gas preheating chamber 8. When the untreated materials quickly approach the heating main furnace 11 and trigger the photoelectric switch, the front insulation door 9 is opened, and the unheat-treated materials quickly enter the heating main furnace 11. At this time, the gas burner 21 of the heating main furnace 11 will burn to produce a large amount of high-temperature flue gas. The generated flue gas first passes through the tail gas preheating 8 to preheat the workpiece, and then passes through the flue gas heat recovery system 22. The combustion-supporting air is preheated by the flue gas heat recovery system 22 and enters the gas burner 21 to increase the combustion temperature and further heat the untreated materials, thereby realizing the utilization of waste heat.

[0040] The above-mentioned feeding process is repeated continuously. When the processed material approaches the rear transition chamber 14 and triggers the photoelectric switch, the rear insulation door 13 opens, and the processed material quickly enters the rear transition chamber 14. After the processed material is located in the rear transition chamber 14 for a process cycle time, the rear transition chamber door 15 opens, and the processed material quickly enters the rear heat exchange chamber 16. The heat in the rear heat exchange chamber 16 is transported to the front heat exchange chamber 3 through the furnace gas heat exchange system 19 to heat the untreated cold material, thereby realizing heat exchange, until the processed material triggers the discharge photoelectric tube in the rear heat exchange chamber 16. At this time, the rear heat exchange chamber door 17 opens, and the heat-treated material quickly enters the discharge platform 18. According to the process cycle time, a basket of heat-treated materials is discharged, and then a basket of untreated materials is fed in. It is controlled by the PLC program and produces continuously for 24 hours.

[0041] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0042] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A continuous waste heat utilization aluminum alloy annealing furnace, comprising a loading platform (1), characterized in that: The left side of the loading platform (1) is fixedly connected to a front heat exchange door (2), the left side of the front heat exchange door (2) is fixedly connected to a front heat exchange chamber (3), the left side of the front heat exchange chamber (3) is fixedly connected to a front transition chamber door (4), the left side of the front transition chamber door (4) is fixedly connected to a front transition chamber (5), and the left side of the front transition chamber (5) is fixedly connected to an exhaust gas preheating heater (6); The left side of the exhaust gas preheating heater (6) is fixedly connected to an exhaust gas preheating chamber (8), a plurality of heat exchange fans (7) are fixedly connected to the exhaust gas preheating chamber (8), and the left side of the exhaust gas preheating chamber (8) is fixedly connected to a front insulation door (9); The left side of the front heat insulation door (9) is fixedly connected to a main heating furnace (11), the main heating furnace (11) is fixedly connected to a furnace body circulation fan (10), a thermocouple (12) is fixedly connected inside the main heating furnace (11), a gas burner (21) is fixedly connected inside the main heating furnace (11), and a flue gas heat recovery system (22) is also arranged inside the main heating furnace (11), the absorption end of the flue gas heat recovery system (22) is located inside the main heating furnace (11), the discharge end of the flue gas heat recovery system (22) is located in the exhaust gas preheating chamber (8), and the absorption end and the discharge end of the flue gas heat recovery system (22) are connected via a pipeline; A rear heat insulation door (13) is fixedly connected to the left side of the main heating furnace (11), a rear transition chamber (14) is fixedly connected to the left side of the rear heat insulation door (13), and a rear transition chamber door (15) is fixedly connected to the left side of the rear transition chamber (14); The left side of the rear transition chamber door (15) is fixedly connected to a rear heat exchange chamber (16), the left side of the rear heat exchange chamber (16) is fixedly connected to a rear heat exchange chamber door (17), the left side of the rear heat exchange chamber door (17) is fixedly connected to a discharge platform (18), and a furnace gas heat exchange system (19) is arranged in the rear heat exchange chamber (16).

2. The continuous waste heat utilization aluminum alloy annealing furnace according to claim 1, characterized in that: One end of a transmission rod (20) is connected to the loading platform (1) via a driving member, and the other end of the transmission rod (20) extends leftward to the position of the unloading platform (18).

3. The continuous waste heat utilization aluminum alloy annealing furnace according to claim 2, characterized in that: The rear heat exchange chamber (16) is connected to the front heat exchange chamber (3) via a double-branch pipeline.

4. The continuous waste heat utilization aluminum alloy annealing furnace according to claim 3, characterized in that: The furnace gas heat exchange system (19) is also arranged in the front heat exchange chamber (3).

5. The continuous waste heat utilization aluminum alloy annealing furnace according to claim 4, characterized in that: The furnace body circulation fan (10) is arranged in each heating zone of the heating main furnace (11).

6. The continuous waste heat utilization aluminum alloy annealing furnace according to claim 5, characterized in that: The front heat insulation door (9) and the rear heat insulation door (13) are both used to isolate the heat in the main furnace (11).

Images