Sintering ring cooling machine waste heat utilization system and method

Abstract

The present application relates to a kind of sintering ring cooling machine waste heat utilization system and method, the system includes sintering ring cooling machine, waste heat boiler and circulating fan;It further includes switching system and variable frequency speed regulation control system;The circulating fan is variable frequency fan;The present application cancels the blower usually configured in the first cooling section of ring cooling machine, waste heat utilization system normal operation or due to equipment maintenance outage, all by circulating fan as the cooling fan of ring cooling machine;Circulating fan uses variable frequency speed regulation fan, and air volume and air pressure are adjusted by variable frequency speed regulation control system, improve the utilization rate of equipment, while reaching the purpose of energy saving and consumption reduction.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of sintering ring cooling, in particular to a sintering ring cooling machine waste heat utilization system and method. BACKGROUND

[0002] In the sinter production process, the sinter sensible heat accounting for nearly 45% of the total heat of the sintering process is cooled by the circulating fan blast in the ring cooling machine, and the hot exhaust gas temperature discharged from the ring cooling machine differs with the cooling position (the average temperature is about 250℃), and the circulating fan circulates the hot air at about 140℃ after heat exchange by the waste heat boiler to the lower air box of the first and second stages of the ring cooling machine. In the case of ensuring the cooling effect of the ring cooling machine, the purpose of improving the air temperature and increasing the waste heat recovery efficiency is achieved.

[0003] In the actual production process, the ring cooling machine flue gas temperature is greatly affected by the sintering process, and the fluctuation of the flue gas temperature leads to unstable operation of the waste heat utilization system; when the waste heat utilization system is overhauled, it will also directly affect the flue gas circulation, leading to unstable operation of the ring cooling machine. Therefore, the ring cooling machine with the waste heat utilization system is usually provided with a blower at the first cooling stage of the ring cooling machine, and the blower is only started when the waste heat utilization system is stopped to ensure the cooling effect of the ring cooling machine, and the blower is stopped when the waste heat utilization system is normally operated, and the first cooling stage of the ring cooling machine is cooled by the circulating fan.

[0004] A Chinese invention patent with the authorized announcement number CN 204854375 U discloses a "ring cooling machine waste heat recovery device", which comprises a ring cooling machine, a smoke hood, a trolley, a sealing system, an upper flue gas pipeline of the ring cooling machine, a waste heat boiler, a circulating fan, a circulating flue, and a blower, wherein the ring cooling machine, the smoke hood, the trolley, and the sealing system constitute a ring cooling zone I and a ring cooling zone II, the upper flue gas pipelines of the ring cooling zone I and the ring cooling zone II are connected to the waste heat boiler, the waste heat boiler outlet is provided with the circulating fan, the circulating fan is connected to the circulating flue, the circulating flue is connected to the air box at the lower part of the trolley of the first cooling zone, the circulating flue is provided with a circulating fan outlet electric butterfly valve, and the blower is connected to the air box at the lower part of the trolley of the first cooling zone, the blower flue is provided with an electric butterfly valve, and the blower flue and the circulating flue are connected in communication.

[0005] The Chinese invention patent with the authorization announcement number CN 216644976 U discloses "a constant-temperature variable-air-volume sintering waste heat utilization system", which comprises a circular cooler, a circular cooler smoke hood, a wind box and a smoke circulation system; the smoke circulation system comprises a wind taking pipeline, a waste heat boiler, a circulating fan connected with the waste heat boiler, a circular cooler return air main pipeline, a return air main branch pipeline, a blower and an automatic control system, the circular cooler smoke hood is a through smoke hood, a high-temperature smoke recovery system, a medium-temperature smoke recovery system and a temperature mixing system are arranged at the upper part of the through circular cooler smoke hood, the high-temperature smoke and the medium-temperature smoke in the circular cooler smoke hood are introduced into the circular cooler waste heat boiler, the hot air after heat exchange of the circular cooler waste heat boiler is pressurized by the circulating fan, and then is returned to the lower part of the circular cooler wind box through the circular cooler return air main pipeline and the return air main branch pipeline, flows through the circular cooler trolley from bottom to top, cools the sintering ore, and is heated to form hot air which is sent to the circular cooler waste heat boiler again, so that the circular utilization is achieved. When the circular cooler waste heat boiler fails and needs to be repaired, the circulating fan is closed and the blower is opened, so that the circular cooler meets the normal operation requirement of the sintering system.

[0006] In the circular cooler waste heat utilization systems of the above two patent documents, the blower and the circulating fan are arranged at the same time, the blower is used as a standby fan of the circulating fan, is only started in the maintenance of the waste heat boiler, has low utilization rate, causes resource waste, and increases the difficulty of equipment and pipeline occupation and process arrangement. SUMMARY

[0007] The application provides a sintering circular cooler waste heat utilization system and method, which cancels the blower usually arranged in the first cooling section of the circular cooler, and the circulating fan is used as the cooling fan of the circular cooler when the waste heat utilization system normally operates or is stopped due to equipment maintenance; the circulating fan is a frequency conversion speed regulation fan, the air volume and air pressure are adjusted through the frequency conversion speed regulation control system, the utilization rate of the equipment is improved, and the purpose of energy saving and consumption reduction is achieved.

[0008] In order to achieve the above purpose, the application adopts the following technical scheme:

[0009] A sintering ring cooler waste heat utilization system, comprising a sintering ring cooler, a waste heat boiler and a circulating fan; a cold section of the ring cooler is provided with a cold section smoke hood connected to the waste heat boiler through a cold section flue, and a second cold section of the ring cooler is provided with a second cold section smoke hood connected to the waste heat boiler through a second cold section flue; the waste heat boiler is connected to the circulating fan through a boiler outlet pipeline, and the circulating fan is connected to a bottom air box of the first cold section and a bottom air box of the second cold section through a blast pipe; the sintering ring cooler waste heat utilization system further comprises a switching system and a variable frequency speed control system; the circulating fan is a variable frequency fan; the variable frequency speed control system is composed of a ring cooler outlet material temperature detection device and a control system, the ring cooler outlet material temperature detection device is arranged at a final cooling section of the ring cooler, and a signal output end of the ring cooler outlet material temperature detection device is connected to a control end of the circulating fan through the control system; the switching system comprises control valves arranged on the cold section flue and the second cold section flue upstream of the waste heat boiler and a control valve arranged on the boiler outlet pipeline; the boiler outlet pipeline upstream of the circulating fan is additionally connected to a cold air supplement pipeline, and a control valve is arranged on the cold air supplement pipeline; and each control valve is connected to a sintering ring cooler control system.

[0010] Further, the ring cooler outlet material temperature detection device is a temperature detection thermocouple.

[0011] Further, the control system is a PLC controller.

[0012] Further, a first section air intake boiler inlet electric valve is arranged on the cold section flue close to an inlet of the waste heat boiler; and a second section air intake boiler inlet electric valve is arranged on the second cold section flue close to the inlet of the waste heat boiler.

[0013] Further, a boiler outlet electric valve is arranged on the boiler outlet pipeline close to an outlet of the waste heat boiler.

[0014] Further, a first section chimney is arranged on the cold section flue, and a first section chimney diffusion valve is arranged on the first section chimney; and a second section chimney is arranged on the second cold section flue, and a second section chimney diffusion valve is arranged on the second section chimney.

[0015] Further, a cold air outlet electric valve is arranged on the cold air supplement pipeline, and a pipeline silencer is arranged at a cold air inlet of the cold air supplement pipeline.

[0016] Further, the blast pipe is connected to the bottom air box of the first cold section through a blast branch pipe one and connected to the bottom air box of the second cold section through a blast branch pipe two, and an electric valve is arranged on each of the blast branch pipe one and the blast branch pipe two, and the electric valves are connected to the sintering ring cooler control system.

[0017] A sintering ring cooler waste heat utilization method, comprising:

[0018] 1) when the waste heat utilization system is in normal operation, the inlet electric valve of the first-stage air extraction boiler, the inlet electric valve of the second-stage air extraction boiler and the outlet electric valve of the boiler are in the open state, the flue gas of the first cooling section of the ring cooler is collected by the first-stage air extraction hood and then sent into the waste heat boiler through the first-stage flue, and the flue gas of the second cooling section of the ring cooler is collected by the second-stage air extraction hood and then sent into the waste heat boiler through the second-stage flue; the flue gas is cooled by the waste heat boiler and then enters the outlet pipeline of the boiler, and is sent into the bottom air box of the first cooling section and the bottom air box of the second cooling section through the air supply pipeline under the action of the circulating fan, so that the sinter on the sintering ring cooler is cooled in circulation;

[0019] 2) when the waste heat utilization system is stopped, the sintering ring cooler control system automatically closes the inlet electric valve of the first-stage air extraction boiler, the inlet electric valve of the second-stage air extraction boiler and the outlet electric valve of the boiler, and simultaneously opens the first-stage chimney diffusion valve, the second-stage chimney diffusion valve and the cold air inlet electric valve, so that the waste heat utilization system is cut off from the sintering ring cooler production system, the flue gas of the first cooling section of the ring cooler and the flue gas of the second cooling section of the ring cooler are diffused through the first-stage chimney and the second-stage chimney, a cold air supply pipeline is arranged on the outlet pipeline of the boiler downstream of the waste heat boiler, the cold air inlet electric valve on the cold air supply pipeline is automatically opened, the circulating fan takes air through the cold air supply pipeline, and the cooling of the sinter in the first cooling section of the ring cooler and the second cooling section of the ring cooler is realized;

[0020] 3) when the waste heat utilization system resumes operation, the sintering ring cooler control system automatically controls the first-stage chimney diffusion valve, the second-stage chimney diffusion valve and the cold air inlet electric valve to be closed, and simultaneously controls the inlet electric valve of the first-stage air extraction boiler, the inlet electric valve of the second-stage air extraction boiler and the outlet electric valve of the boiler to be opened, so that the automatic switching of the waste heat utilization system in the two states of opening and stopping is realized, and the normal operation of the sintering ring cooler is not affected in the process.

[0021] Compared with the prior art, the beneficial effects of the present application are:

[0022] The first cooling section of the ring cooler is usually provided with a blower, and when the waste heat utilization system is in normal operation or is stopped due to equipment maintenance, the circulating fan is used as the cooling fan of the ring cooler; the circulating fan is a variable frequency speed regulating fan, the air volume and air pressure are adjusted through the variable frequency speed regulating control system, the utilization rate of the equipment is improved, and the purpose of energy saving and consumption reduction is achieved. BRIEF DESCRIPTION OF DRAWINGS

[0023] Figure 1 is a structural schematic view of a sintering ring cooler waste heat utilization system.

[0024] In the figure: 1. sintering ring cooler 2. waste heat boiler 3. circulating fan 4. one-stage blast fan of ring cooler 5. one-stage chimney emission valve 6. one-stage air intake boiler inlet electric valve 7. two-stage chimney emission valve 8. two-stage air intake boiler inlet electric valve 9. boiler outlet electric valve 10. cold air outlet electric valve 11. cold air supplement pipeline 12. pipeline silencer 13. ring cooler outlet material temperature detection device DETAILED DESCRIPTION

[0025] The specific embodiment of the present application is further illustrated below in combination with the accompanying drawings:

[0026] As Figure 1 , the sintering ring cooler waste heat utilization system comprises a sintering ring cooler 1, a waste heat boiler 2 and a circulating fan 3; a one-stage cold section of the ring cooler is provided with a one-stage cold section fume hood connected to the waste heat boiler 2 through a one-stage flue, and a two-stage cold section of the ring cooler is provided with a two-stage cold section fume hood connected to the waste heat boiler 2 through a two-stage flue; the waste heat boiler 2 is connected to the circulating fan 3 through a boiler outlet pipeline, and the circulating fan 3 is connected to a one-stage bottom air box and a two-stage bottom air box through a blast pipeline; the sintering ring cooler waste heat utilization system further comprises a switching system and a variable frequency speed control system; the circulating fan 3 is a variable frequency fan; the variable frequency speed control system is composed of a ring cooler outlet material temperature detection device 13 and a control system, the ring cooler outlet material temperature detection device 13 is arranged at the last cold section of the ring cooler, and a signal output end of the ring cooler outlet material temperature detection device 13 is connected to a control end of the circulating fan 3 through the control system; the switching system comprises control valves arranged on the one-stage flue and the two-stage flue upstream of the waste heat boiler 2, and a control valve arranged on the boiler outlet pipeline; the boiler outlet pipeline upstream of the circulating fan 3 is additionally connected to a cold air supplement pipeline 11, and the cold air supplement pipeline 11 is provided with a control valve; each control valve is connected to a sintering ring cooler control system.

[0027] Further, the ring cooler outlet material temperature detection device 13 is a temperature detection thermocouple.

[0028] Further, the control system is a PLC controller.

[0029] Further, the one-stage flue is provided with a one-stage air intake boiler inlet electric valve 6 near the waste heat boiler inlet; and the two-stage flue is provided with a two-stage air intake boiler inlet electric valve 8 near the waste heat boiler inlet.

[0030] Further, the boiler outlet pipeline is provided with a boiler outlet electric valve 9 near the waste heat boiler outlet.

[0031] Further, the one-stage flue is provided with a one-stage chimney, and the one-stage chimney is provided with a one-stage chimney emission valve 5; and the two-stage flue is provided with a two-stage chimney, and the two-stage chimney is provided with a two-stage chimney emission valve 7.

[0032] Further, the cold air outlet electric valve 10 is arranged on the cold air supplement pipeline 11, and a pipeline silencer 12 is arranged at the cold air inlet of the cold air supplement pipeline 11.

[0033] Further, the air supply pipeline is connected with a cold section bottom air box through air supply branch pipe one and connected with two cold section bottom air boxes through air supply branch pipe two, and electric valves are arranged on the air supply branch pipe one and the air supply branch pipe two respectively, and the electric valves are connected with the sintering ring cooler control system.

[0034] As shown in Figure 1 The sintering ring cooler waste heat utilization method comprises the following steps:

[0035] 1) When the waste heat utilization system is normally running, the one-section air intake boiler inlet electric valve 6, the two-section air intake boiler inlet electric valve 8 and the boiler outlet electric valve 9 are all in the open state, the flue gas of the one cold section of the ring cooler is collected by the one cold section smoke hood and then sent into the waste heat boiler 2 through the one cold section flue, the flue gas of the two cold section of the ring cooler is collected by the two cold section smoke hood and then sent into the waste heat boiler 2 through the two cold section flue, the flue gas is cooled by heat exchange in the waste heat boiler 2 and then enters the boiler outlet pipeline, and under the action of the circulating fan, the flue gas is sent into the one cold section bottom air box and the two cold section bottom air box through the air supply pipeline, so as to circularly cool the sinter on the sintering ring cooler 1.

[0036] 2) When the waste heat utilization system is stopped due to equipment maintenance and the like, the sintering ring cooler control system automatically closes the one-section air intake boiler inlet electric valve 6, the two-section air intake boiler inlet electric valve 8 and the boiler outlet electric valve 9, and simultaneously opens the one-section chimney diffusion valve 5, the two-section chimney diffusion valve 7 and the cold air outlet electric valve 10, so as to cut off the waste heat utilization system from the sintering ring cooler production system, the flue gas of the one cold section of the ring cooler and the flue gas of the two cold section of the ring cooler are diffused through the one cold section chimney and the two cold section chimney, a cold air supplement pipeline 11 is arranged on the boiler outlet pipeline downstream of the waste heat boiler 2, the cold air outlet electric valve 10 on the cold air supplement pipeline 11 is automatically opened, and the circulating fan 3 takes air through the cold air supplement pipeline 11, so as to cool the sinter in the one cold section of the ring cooler and the two cold section of the ring cooler.

[0037] 3) When the waste heat utilization system resumes running, the sintering ring cooler control system automatically controls the one-section chimney diffusion valve 5, the two-section chimney diffusion valve 7 and the cold air outlet electric valve 10 to be closed, and simultaneously controls the one-section air intake boiler inlet electric valve 6, the two-section air intake boiler inlet electric valve 8 and the boiler outlet electric valve 9 to be opened, so as to realize the automatic switching of the waste heat utilization system in the two states of opening and stopping, and in this process, the normal running of the sintering ring cooler 1 is not affected.

[0038] The sintering ring cooler waste heat utilization system (referred to as the waste heat utilization system) cancels the one-section air blower 4 of the conventional sintering ring cooler waste heat utilization system as a standby blower (as shown in Figure 1The circulating fan 3 is a variable frequency fan, and a variable frequency control system is configured. The air volume and air pressure of the circulating fan 3 are usually set to be the total air volume of the air volume of the first cooling section and the air volume of the second cooling section, which are much larger than the corresponding parameters of the first cooling fan 4. If the circulating fan 3 is a fixed frequency fan, great energy consumption and waste will be caused when the waste heat utilization system is stopped. The variable frequency control system can adjust the air volume and air pressure of the circulating fan 3 in real time according to the air volume required by the ring cooling machine, so that the purpose of energy saving and consumption reduction is achieved. At the same time, the variable frequency control system can better adapt to the frequent changes of the flue gas volume and pressure when the waste heat utilization system is in normal operation.

[0039] The circulating fan 3 is a variable frequency fan, and a variable frequency control system is configured. The air volume and air pressure of the circulating fan 3 are usually set to be the total air volume of the air volume of the first cooling section and the air volume of the second cooling section, which are much larger than the corresponding parameters of the first cooling fan 4. If the circulating fan 3 is a fixed frequency fan, great energy consumption and waste will be caused when the waste heat utilization system is stopped. The variable frequency control system can adjust the air volume and air pressure of the circulating fan 3 in real time according to the air volume required by the ring cooling machine, so that the purpose of energy saving and consumption reduction is achieved. At the same time, the variable frequency control system can better adapt to the frequent changes of the flue gas volume and pressure when the waste heat utilization system is in normal operation.

[0040] The control end (frequency converter) of the circulating fan 3 is interlocked with the ring cooling machine outlet material temperature detection device 13. The corresponding values of temperature and air volume are pre-set in the control system, and the air volume of the circulating fan 3 is automatically adjusted according to the temperature change, that is, the air volume is increased when the temperature is increased, and the air volume is reduced when the temperature is reduced.

[0041] A pipeline silencer 12 is arranged at the cold air inlet of the cold air supplement pipeline 11 to eliminate the noise during air taking.

[0042] The above is only the preferred specific embodiment of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art can make equivalent replacement or change according to the technical solution and concept of the present application within the technical range disclosed by the present application, which should be covered in the protection scope of the present application.

Claims

1. A sintering ring cooler waste heat utilization system, comprising a sintering ring cooler, a waste heat boiler and a circulating fan; a cold section of the ring cooler is provided with a cold section fume hood connected to the waste heat boiler through a cold section flue, and a second cold section of the ring cooler is provided with a second cold section fume hood connected to the waste heat boiler through a second cold section flue; the waste heat boiler is connected to the circulating fan through a boiler outlet pipeline, and the circulating fan is connected to a bottom air box of the cold section and a bottom air box of the second cold section through an air supply pipeline; characterized in that, The sintering ring cooler waste heat utilization system further comprises a switching system and a variable frequency speed control system; the circulating fan is a variable frequency fan; the variable frequency speed control system is composed of a ring cooler outlet material temperature detection device and a control system; the ring cooler outlet material temperature detection device is arranged at the final cooling section of the ring cooler; the signal output end of the ring cooler outlet material temperature detection device is connected to the control end of the circulating fan through the control system; the switching system comprises control valves arranged on the flue ducts of the first cooling section and the second cooling section upstream of the waste heat boiler and a control valve arranged on the boiler outlet pipeline; the boiler outlet pipeline upstream of the circulating fan is connected to a cold air supplement pipeline, and a control valve is arranged on the cold air supplement pipeline; each control valve is connected to the sintering ring cooler control system; an electric valve is arranged at the inlet of the first section air taking boiler near the inlet of the waste heat boiler; an electric valve is arranged at the inlet of the second section air taking boiler near the inlet of the waste heat boiler; a first section chimney is arranged on the first section flue duct, and a first section chimney emission valve is arranged on the first section chimney; a second section chimney is arranged on the second section flue duct, and a second section chimney emission valve is arranged on the second section chimney; the air supply pipeline is connected to the bottom air box of the first cooling section through air supply branch pipe one and connected to the bottom air box of the second cooling section through air supply branch pipe two; electric valves are arranged on the air supply branch pipe one and the air supply branch pipe two, and the electric valves are connected to the sintering ring cooler control system.

2. The sinter ring cooler waste heat utilization system according to claim 1, characterized in that, The ring cooler outlet material temperature detection device is a temperature detection thermocouple.

3. The sinter ring cooler waste heat utilization system according to claim 1, characterized in that, The control system is a PLC controller.

4. The sinter ring cooler waste heat utilization system according to claim 1, characterized in that, An electric valve is arranged at the outlet of the boiler near the outlet of the waste heat boiler.

5. The sinter ring cooler waste heat utilization system according to claim 1, characterized in that, An electric valve is arranged on the cold air inlet of the cold air supplement pipeline, and a pipeline silencer is arranged at the cold air inlet of the cold air supplement pipeline.

6. The sintering ring cooler waste heat utilization method based on the system according to any one of claims 1 to 5, characterized by, The method comprises the following steps: 1) When the waste heat utilization system is in normal operation, the first section air taking boiler inlet electric valve, the second section air taking boiler inlet electric valve and the boiler outlet electric valve are all in the open state; the flue gas of the first cooling section of the ring cooler is collected by the first section flue hood and then sent into the waste heat boiler through the first section flue duct; the flue gas of the second cooling section of the ring cooler is collected by the second section flue hood and then sent into the waste heat boiler through the second section flue duct; the flue gas is cooled by heat exchange in the waste heat boiler and then enters the boiler outlet pipeline; the flue gas is sent into the bottom air box of the first cooling section and the bottom air box of the second cooling section through the air supply pipeline under the action of the circulating fan, so as to circularly cool the sinter on the sintering ring cooler; 2) When the waste heat utilization system is stopped, the sintering ring cooler control system automatically closes the first section air taking boiler inlet electric valve, the second section air taking boiler inlet electric valve and the boiler outlet electric valve, and simultaneously opens the first section chimney emission valve, the second section chimney emission valve and the cold air inlet electric valve, so as to cut off the waste heat utilization system from the sintering ring cooler production system; the flue gas of the first cooling section of the ring cooler and the flue gas of the second cooling section of the ring cooler are emitted through the first section chimney and the second section chimney; a cold air supplement pipeline is arranged on the boiler outlet pipeline downstream of the waste heat boiler; the cold air inlet electric valve on the cold air supplement pipeline is automatically opened; the circulating fan takes air through the cold air supplement pipeline, so as to cool the sinter in the first cooling section of the ring cooler and the second cooling section of the ring cooler. 3) When the waste heat utilization system resumes operation, the sintering circular cooler control system automatically controls the first-stage chimney emission valve, the second-stage chimney emission valve and the cold air inlet electric valve to be closed, and simultaneously controls the first-stage air extraction boiler inlet electric valve, the second-stage air extraction boiler inlet electric valve and the boiler outlet electric valve to be opened, so as to realize automatic switching of the waste heat utilization system in the two states of opening and shutdown, without affecting the normal operation of the sintering circular cooler.

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