System for recovering waste heat and working medium of diffused steam of dry quenching boiler

Abstract

The invention relates to a system for recovering waste heat and working media of diffused steam of a coke dry quenching boiler, which comprises the coke dry quenching boiler, a main steam pipeline, a steam turbine generator unit, a high-pressure dead steam waste heat utilization pipeline, high-temperature dead steam temperature and pressure reduction equipment, a low-pressure steam pipe network, a self-deoxidizing system and a recycling system, the dry quenching boiler is connected with the steam turbine generator unit through a main steam pipeline, and a high-pressure dead steam waste heat utilization pipeline is arranged on the main steam pipeline and connected with high-temperature dead steam temperature and pressure reduction equipment. The high-temperature dead steam temperature and pressure reduction device has the beneficial effects that the problem of energy waste caused by steam diffusion is solved, the production cost is reduced, white smoke elimination is achieved, the environmental protection requirement is met, the practicability is high, the application range is wide, and the economic value is high.

Description

Technical Field

[0001] The invention relates to the technical field of recovery and reuse of waste heat from dry coke quenching, and in particular to a system for recovering waste heat and working fluid from steam released by a dry coke quenching boiler. Background Art

[0002] The dry coke quenching waste heat power generation technology uses the dry coke quenching boiler to absorb the heat of the circulating gas to generate steam for the steam turbine generator to generate electricity. In recent years, the dry coke quenching waste heat power generation technology has developed rapidly and has been widely used in the steel coking industry. In the early stage of dry coke quenching, it is often the case that the dry coke quenching boiler has been put into operation but the steam turbine generator has not been put into operation. Under this condition, the dry coke quenching boiler is generally in a low-load operation state of 10% to 30%, generating superheated steam of about 5.0MPa and 450℃ to 500℃. At this time, the steam generated by the dry coke quenching boiler will be released through the main steam release pipeline through the silencer, resulting in energy waste and producing "white smoke", which is not conducive to environmental protection.

[0003] Therefore, it is necessary to recycle and reuse the emitted steam generated by the CDQ boiler, which can not only solve the problem of energy waste but also meet environmental protection requirements. Summary of the invention

[0004] In order to overcome the shortcomings of the prior art, the present invention provides a system for recovering the waste heat and working fluid of the discharged steam of the dry quenching boiler, and the discharged steam generated by the dry quenching boiler is sent to three places after being cooled and depressurized. First, it is incorporated into the low-pressure steam pipeline network; second, it is sent to its own deoxygenation system; third, the working fluid is recovered and reused through low-temperature cooling and pressure reduction equipment and exhaust steam condensing equipment.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] A system for recovering steam waste heat and working fluid released by a dry coke quenching boiler comprises a dry coke quenching boiler, a main steam pipeline, a steam turbine generator set, a high-pressure exhaust steam waste heat utilization pipeline, a high-temperature exhaust steam temperature reduction and pressure reduction device, a low-pressure steam pipeline network, a self-deoxygenation system and a recovery and reuse system. The dry coke quenching boiler is connected to the steam turbine generator set through the main steam pipeline, a high-pressure exhaust steam waste heat utilization pipeline is arranged on the main steam pipeline, the high-pressure exhaust steam waste heat utilization pipeline is connected to the high-temperature exhaust steam temperature reduction and pressure reduction device, and the high-temperature exhaust steam temperature reduction and pressure reduction device is respectively connected to the low-pressure steam pipeline network, the self-deoxygenation system and the recovery and reuse system.

[0007] Furthermore, the recycling and reuse system includes low-temperature cooling and pressure reduction equipment, exhaust steam condensing equipment, desalting water tank and cooling water pump. The air outlet of the high-pressure exhaust steam cooling and pressure reduction equipment is provided with a 0.6MPa low-pressure steam pipeline connected to the air inlet of the low-temperature cooling and pressure reduction equipment. The air outlet of the low-temperature cooling and pressure reduction equipment is provided with a 0.02MPa ultra-low-pressure steam pipeline connected to the air inlet of the exhaust steam condensing equipment. The water outlet of the exhaust steam condensing equipment is provided with a condensate recovery pipeline connected to the water inlet of the desalting water tank. The water outlet of the desalting water tank is provided with a cooling water pipeline. A cooling water pump is provided on the cooling water pipeline. The cooling water pipeline on the outlet side of the cooling water pump is divided into two routes, and the two cooling water pipelines are respectively connected to the high-temperature exhaust steam cooling and pressure reduction equipment and the low-temperature cooling and pressure reduction equipment.

[0008] Furthermore, the self-deoxygenation system includes a deaerator, and a low-pressure deoxygenation pipeline is arranged at the inlet of the deaerator to connect with the high-temperature exhaust steam temperature and pressure reduction equipment.

[0009] Furthermore, the main steam pipeline is provided with a main steam release pipeline at the outlet of the dry coke quenching boiler, and a muffler and an electric valve are provided on the main steam release pipeline.

[0010] Furthermore, the high-pressure exhaust steam waste heat utilization pipeline is provided with a temperature and pressure reducing valve, a remote temperature control instrument and a remote pressure control instrument.

[0011] Furthermore, the two cooling water pipelines are respectively provided with a stop valve, a filter, a throttle valve, a water supply regulating valve and a check valve in sequence, and the opening of the water supply regulating valve is controlled by a remote temperature control instrument.

[0012] Furthermore, the exhaust steam condensing equipment is provided with a vacuum pipeline connected to a water ring vacuum pump equipment.

[0013] Furthermore, the exhaust steam condensing equipment is connected to the circulating cooling water supply and the circulating cooling water return.

[0014] Furthermore, the desalted water tank is externally connected to a desalted water replenishment pipeline.

[0015] Furthermore, a pressure-controlled regulating valve is provided between the high-pressure exhaust steam waste heat utilization pipeline and the low-pressure steam pipeline network.

[0016] Compared with the prior art, the present invention has the following beneficial effects:

[0017] 1. The present invention sends the steam generated by the dry quenching boiler, which would otherwise be released through the main steam release pipeline through the muffler, to three locations: one is to be incorporated into the low-pressure steam network; the second is to be sent to its own deoxygenation system; and the third is to recycle and reuse the working fluid through low-temperature temperature and pressure reduction equipment and exhaust steam condensing equipment. This not only solves the problem of energy waste caused by steam release and reduces production costs, but also achieves "whitening" and meets environmental protection requirements.

[0018] 2. A pressure-controlled regulating valve is installed between the high-pressure exhaust steam waste heat utilization pipeline and the low-pressure steam pipeline network to meet the application of this system under different working conditions and provide different low-pressure steam volumes for different routes to meet the personalized needs of actual projects. It has strong practicality, a wide range of applications and high economic value. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 The present invention discloses a system process flow chart for recovering waste heat and working fluid of steam released by a dry coke quenching boiler.

[0020] In the figure: 1. CDQ boiler; 2. Main steam pipeline; 3. Steam turbine generator set; 4. Main steam release pipeline; 5. Muffler; 6. High-pressure exhaust steam waste heat utilization pipeline; 7. High-temperature exhaust steam temperature and pressure reduction equipment; 8. 0.6MPa low-pressure steam pipeline; 9. Deaerator; 10. Low-temperature temperature and pressure reduction equipment; 11. 0.02MPa ultra-low-pressure steam pipeline; 12. Exhaust steam condensing equipment; 13. Circulating cooling water supply pipeline; 14. Circulating cooling water return pipeline; 15. Condensate recovery pipeline; 16. Desalted water tank; 17. Desuperheating water pump; 18. Desuperheating water pipeline; 19. Desalted water replenishment pipeline; 20. Water ring vacuum pump equipment; 21. Vacuuming pipeline. DETAILED DESCRIPTION

[0021] The specific implementation of the present invention will be further described below in conjunction with the accompanying drawings:

[0022] like Figure 1 As shown, a system for recovering steam waste heat and working fluid released by a dry coke quenching boiler comprises a dry coke quenching boiler 1, a main steam pipeline 2, a steam turbine generator set 3, a high-pressure exhaust steam waste heat utilization pipeline 6, a high-temperature exhaust steam temperature reduction and pressure reduction device 7, a low-pressure steam pipeline network, a self-deoxygenation system and a recovery and reuse system. The dry coke quenching boiler 1 is connected to the steam turbine generator set 3 through the main steam pipeline 2, and a high-pressure exhaust steam waste heat utilization pipeline 6 is arranged on the main steam pipeline 2. The high-pressure exhaust steam waste heat utilization pipeline 6 is connected to the high-temperature exhaust steam temperature reduction and pressure reduction device 7, and the high-temperature exhaust steam temperature reduction and pressure reduction device 7 is respectively connected to the low-pressure steam pipeline network, the self-deoxygenation system and the recovery and reuse system. At the initial stage of coke quenching, the 5.0MPa, 450-500℃ vent steam generated by the dry quenching boiler 1 is vented through the main steam vent pipe 4 through the muffler 5. The high-pressure exhaust steam waste heat utilization pipe 6, the main steam vent pipe 4 and the main steam pipe 2 are respectively provided with electric valves for switching the vent steam. The vent steam can be sent to the high-temperature exhaust steam temperature reduction and pressure reduction equipment 7 through the high-pressure exhaust steam waste heat utilization pipe 6 through the electric valve control. The generated low-pressure steam can be sent to three places: one is to be incorporated into the low-pressure steam network, the second is to be used for its own deoxygenation system, and the third is to recycle the working medium through the low-temperature temperature reduction and pressure reduction equipment 10 and the exhaust steam condensing equipment 12.

[0023] Furthermore, the recycling system includes a low-temperature cooling and pressure reduction device 10, an exhaust steam condensing device 12, a desalted water tank 16 and a cooling water pump 17. The outlet of the high-pressure exhaust steam cooling and pressure reduction device 7 is provided with a 0.6MPa low-pressure steam pipeline 8 connected to the air inlet of the low-temperature cooling and pressure reduction device 10, the outlet of the low-temperature cooling and pressure reduction device 10 is provided with a 0.02MPa ultra-low-pressure steam pipeline 11 connected to the air inlet of the exhaust steam condensing device 12, and the outlet of the exhaust steam condensing device 12 is provided with a A condensate recovery pipeline 15 is arranged to be connected to the water inlet of the desalted water tank 16, a cooling water pipeline 18 is arranged at the water outlet of the desalted water tank 16, a cooling water pump 17 is arranged on the cooling water pipeline 18, the cooling water pipeline 18 on the outlet side of the cooling water pump 17 is divided into two paths, the two cooling water pipelines 18 are respectively connected to the high-temperature exhaust steam cooling and pressure reduction equipment 7 and the low-temperature cooling and pressure reduction equipment 10, the two cooling water pipelines 18 provide cooling water for the high-temperature exhaust steam cooling and pressure reduction equipment 7 and the low-temperature cooling and pressure reduction equipment 10.

[0024] Furthermore, the self-deoxygenation system includes a deaerator 9, and a low-pressure deoxygenation pipeline is arranged at the inlet of the deaerator 9 to connect with the high-temperature exhaust steam temperature and pressure reduction equipment 7.

[0025] Furthermore, the main steam pipeline 2 is connected to a main steam release pipeline 4 at the outlet of the dry coke quenching boiler 1 , and a muffler 5 and an electric valve are arranged on the main steam release pipeline 4 .

[0026] Furthermore, the high-pressure exhaust steam waste heat utilization pipeline 6 is provided with a temperature reduction and pressure reducing valve, a remote temperature control instrument and a remote pressure control instrument for controlling the temperature and pressure of the low-pressure steam at the outlet of the high-temperature exhaust steam temperature reduction and pressure reducing equipment 7 .

[0027] Furthermore, the two cooling water pipelines 18 are respectively provided with a stop valve, a filter, a throttle valve, a water supply regulating valve and a check valve in sequence, and the opening of the water supply regulating valve is controlled by a remote temperature control instrument.

[0028] Furthermore, the exhaust steam condensing equipment 12 is connected to the water ring vacuum pump equipment 20 via a vacuum pipeline 21 , and the water ring vacuum pump equipment 20 evacuates the exhaust steam condensing equipment 12 .

[0029] Furthermore, the exhaust steam condensing equipment 12 is connected to the circulating cooling water supply 13 and the circulating cooling water return 14 .

[0030] Furthermore, the desalted water tank 16 is externally connected to a desalted water replenishment pipeline 19 .

[0031] Furthermore, a pressure-controlled regulating valve is provided between the high-pressure exhaust steam waste heat utilization pipeline 6 and the low-pressure steam pipeline network.

[0032] like Figure 1 As shown, a working method of a system for recovering waste heat and working fluid released by a dry coke quenching boiler:

[0033] S1, the electric valves of the main steam pipeline 2 and the main steam release pipeline 4 of the steam outlet of the dry coke quenching boiler 1 are closed, the electric valve of the high-pressure exhaust steam waste heat utilization pipeline 6 is opened, and the high-temperature steam is sent to the high-temperature exhaust steam temperature and pressure reduction equipment 7 through the high-pressure exhaust steam waste heat utilization pipeline 6;

[0034] S2, high-temperature steam is cooled and decompressed into low-pressure steam by high-temperature exhaust steam cooling and decompression equipment 7, and the low-pressure steam is divided into three routes: one is to be incorporated into the low-pressure steam network, the second is to be used for its own deoxygenation system, and the third is to be recycled and reused by low-temperature cooling and decompression equipment 10 and exhaust steam condensing equipment 12;

[0035] S3, low-pressure steam is sent to the low-temperature temperature reduction and pressure reduction equipment 10 through the 0.6MPa low-pressure steam pipeline 8 for further temperature reduction and pressure reduction, and the low-pressure steam is then sent to the exhaust steam condensing equipment 12 through the 0.02MPa ultra-low-pressure steam pipeline 11, and the low-pressure steam condenses into condensed water through the exhaust steam condensing equipment 12;

[0036] S4. The condensed water is sent to the desalted water tank 16 through the condensed water recovery pipeline 15. The desalted water is introduced into the desalted water tank 16. The condensed water passes through the desalted water tank 16 to generate cooling water. The cooling water is divided into two ways through the cooling water pipeline 18 to connect to the high-pressure exhaust steam cooling and pressure reduction equipment 7 and the low-temperature cooling and pressure reduction equipment 10 to participate in the cooling and pressure reduction of the high-temperature steam, so as to recover and reuse the discharged steam working medium and waste heat of the dry coke quenching boiler 1.

[0037] The above description is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical solutions and concepts of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A system for recovering steam waste heat and working fluid released by a dry coke quenching boiler, comprising a dry coke quenching boiler, a main steam pipeline, a steam turbine generator set, a high-pressure exhaust steam waste heat utilization pipeline, a high-temperature exhaust steam temperature and pressure reduction device, a low-pressure steam pipeline network, a self-deoxygenation system and a recovery and reuse system, wherein the dry coke quenching boiler is connected to the steam turbine generator set through the main steam pipeline, and is characterized in that: A high-pressure exhaust steam waste heat utilization pipeline is arranged on the main steam pipeline, and the high-pressure exhaust steam waste heat utilization pipeline is connected to the high-temperature exhaust steam temperature reduction and pressure reduction equipment, and the high-temperature exhaust steam temperature reduction and pressure reduction equipment is respectively connected to the low-pressure steam pipeline network, its own deoxygenation system and the recovery and reuse system.

2. A system for recovering waste heat and working fluid from steam released by a dry coke quenching boiler according to claim 1, characterized in that: The recycling system includes low-temperature cooling and pressure reduction equipment, exhaust steam condensing equipment, desalting water tank and cooling water pump. The air outlet of the high-pressure exhaust steam cooling and pressure reduction equipment is provided with a 0.6MPa low-pressure steam pipeline connected to the air inlet of the low-temperature cooling and pressure reduction equipment. The air outlet of the low-temperature cooling and pressure reduction equipment is provided with a 0.02MPa ultra-low-pressure steam pipeline connected to the air inlet of the exhaust steam condensing equipment. The water outlet of the exhaust steam condensing equipment is provided with a condensate recovery pipeline connected to the water inlet of the desalting water tank. The water outlet of the desalting water tank is provided with a cooling water pipeline. A cooling water pump is provided on the cooling water pipeline. The cooling water pipeline on the outlet side of the cooling water pump is divided into two paths. The two cooling water pipelines are respectively connected to the high-temperature exhaust steam cooling and pressure reduction equipment and the low-temperature cooling and pressure reduction equipment.

3. The system for recovering waste heat and working fluid from steam released by a dry coke quenching boiler according to claim 1 is characterized in that: The self-deoxygenation system comprises a deaerator, and a low-pressure deoxygenation pipeline is arranged at the inlet of the deaerator to connect with the high-temperature exhaust steam temperature and pressure reduction equipment.

4. The system for recovering waste heat and working fluid from steam released by a dry coke quenching boiler according to claim 1 is characterized in that: The main steam pipeline is provided with a main steam release pipeline at the outlet of the dry coke quenching boiler, and a muffler and an electric valve are provided on the main steam release pipeline.

5. The system for recovering waste heat and working fluid from steam released by a dry coke quenching boiler according to claim 1 is characterized in that: The high-pressure exhaust steam waste heat utilization pipeline is provided with a temperature reduction and pressure reducing valve, a remote temperature control instrument and a remote pressure control instrument.

6. A system for recovering waste heat and working fluid from steam released by a dry coke quenching boiler according to claim 2, characterized in that: The two cooling water pipelines are respectively provided with a stop valve, a filter, a throttle valve, a water supply regulating valve and a check valve in sequence, and the opening of the water supply regulating valve is controlled by a remote temperature control instrument.

7. The system for recovering waste heat and working fluid from steam released by a dry coke quenching boiler according to claim 2, characterized in that: The exhaust steam condensing equipment is provided with a vacuum pipeline to connect with the water ring vacuum pump equipment.

8. The system for recovering waste heat and working fluid from steam released by a dry coke quenching boiler according to claim 2, characterized in that: The exhaust steam condensing equipment is connected to the circulating cooling water supply and the circulating cooling water return.

9. The system for recovering waste heat and working fluid from steam released by a dry coke quenching boiler according to claim 2, characterized in that: The desalted water tank is externally connected to a desalted water replenishment pipeline.

10. The system for recovering waste heat and working fluid from steam released by a dry coke quenching boiler according to claim 1, characterized in that: A pressure-controlled regulating valve is arranged between the high-pressure exhaust steam waste heat utilization pipeline and the low-pressure steam pipeline network.

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