A high-pressure bypass connection system for a vertical heat recovery coke waste heat boiler

Abstract

The utility model provides a kind of high-pressure bypass connection system of vertical heat recovery coke thermoelectric waste heat boiler, belongs to vertical heat recovery coke thermoelectric waste heat boiler technical field, comprising: superheater, reheater, steam turbine and high-pressure bypass system, high-pressure bypass system is arranged between superheater and reheater, high-pressure bypass system includes high-pressure bypass pipeline, high-pressure bypass device, valve A and valve B, two ends of high-pressure bypass pipeline are connected with connection pipe A and connection pipe B respectively, and high-pressure bypass device, valve A and valve B are respectively arranged on high-pressure bypass pipeline. By adding high-pressure bypass system between reheater and superheater of waste gas waste heat boiler, the purpose of balancing the difference between boiler steam production and steam turbine steam consumption while protecting reheater is achieved, thereby improving the stability of the entire system operation.

Description

Technical Field

[0001] This utility model belongs to the technical field of vertical heat recovery coke-electric waste heat boilers, specifically relating to a high-pressure bypass connection system for a vertical heat recovery coke-electric waste heat boiler. Background Technology

[0002] Heat recovery coke ovens are available in two types: vertical and horizontal. In vertical heat recovery coke ovens, the high-temperature waste gas produced after combustion of raw coal gas reaches temperatures as high as 1100℃. To fully recover this heat, a waste heat boiler converts the high-temperature waste gas into electricity, thereby promoting the transformation of the coking industry towards green and energy-saving practices. With the advancement of my country's thermal power technology and equipment manufacturing, the parameters of waste heat boilers have been upgraded from medium temperature and medium pressure to ultra-high temperature and ultra-high pressure. Furthermore, to further improve the sensible heat recovery efficiency, ultra-high temperature and ultra-high pressure boilers are typically equipped with reheaters.

[0003] However, due to the unique nature of the vertical heat recovery coke oven process, the waste heat boiler and the steam turbine cannot be installed adjacent to each other. Typically, the distance between the two facilities is 100-300m, and the pipelines between them are connected through a pipe gallery. When the steam turbine is not in operation, the main steam needs to be transmitted through the pipe gallery to the desuperheating and pressure reducing device, and then returned to the boiler reheater through the pipe gallery to absorb heat. However, this method has a long travel time.

[0004] Currently, in traditional dry quenching waste heat boiler systems, insufficient flow in the reheater during boiler start-up or turbine failure can easily lead to localized overheating or even dry burning. For example, when the turbine shuts down due to a malfunction, steam circulation within the reheater is interrupted, heat cannot be transferred in time, and the tube wall temperature rises sharply, increasing the risk of coking, corrosion, and even tube rupture, significantly reducing the safety and stability of the reheater. Furthermore, when the boiler is operating at high load, insufficient steam intake can cause a decrease in turbine efficiency, while at low turbine load, excess boiler steam can easily lead to overpressure risks, resulting in production interruptions.

[0005] Therefore, there is an urgent need for a solution that can both protect the reheater and balance the difference between the boiler steam production and the steam consumption of the turbine, so as to ensure the stable operation of the system. Utility Model Content

[0006] Based on the above-mentioned technical problems, the purpose of this utility model is to provide a high-pressure bypass connection system for a vertical heat recovery coke oven waste heat boiler. By adding a high-pressure bypass system between the reheater and superheater of the waste heat boiler, the reheater can be protected while balancing the difference between the boiler steam production and the steam consumption of the turbine, thereby improving the stability of the entire system operation.

[0007] The specific technical solution is as follows: A high-pressure bypass connection system for a vertical heat recovery coke oven waste heat boiler includes: a superheater, a reheater, a steam turbine, and a high-pressure bypass system. The steam outlet of the superheater is connected to the high-pressure cylinder inlet of the steam turbine via connecting pipe A. The high-pressure cylinder outlet of the steam turbine is connected to the steam inlet of the reheater via connecting pipe B. The steam outlet A of the reheater is connected to the low-pressure cylinder inlet of the steam turbine via connecting pipe C. The steam outlet B of the reheater is connected to the outside air. The high-pressure bypass system is located between the superheater and the reheater. The high-pressure bypass system includes a high-pressure bypass pipe, a high-pressure bypass device, valve A, and valve B. The two ends of the high-pressure bypass pipe are connected to connecting pipe A and connecting pipe B, respectively. The high-pressure bypass device, valve A, and valve B are respectively installed on the high-pressure bypass pipe. Valve C and valve D are respectively installed on connecting pipe A and connecting pipe B.

[0008] In addition, the high-pressure bypass connection system of the vertical heat recovery coke oven waste heat boiler provided by this utility model may also have the following additional technical features: In the above technical solution, the output end of the desuperheating water pipeline is connected to the high-pressure bypass device.

[0009] In the above technical solution, the inlet end of the desuperheating water pipe is connected to the intermediate tap of the boiler feed water pump.

[0010] In the above technical solution, a temperature sensor and a pressure sensor are installed on the high-pressure bypass pipeline, and the temperature sensor and pressure sensor are located at the outlet of the high-pressure bypass device.

[0011] The high-pressure bypass connection system of the vertical heat recovery coke oven waste heat boiler of this utility model has the following advantages compared with the prior art: 1. By adding a high-pressure bypass system between the superheater and the reheater, when the boiler is started up or a turbine accident occurs, valves C and D are closed, and valves A and B are opened. This allows the main steam to enter the high-pressure bypass device through the high-pressure bypass pipeline, where it is de-heated and depressurized before entering the reheater. This ensures that there is always steam flow in the reheater, preventing local overheating, pipe wall coking, or equipment damage caused by dry burning.

[0012] 2. When a turbine accident occurs, the high-pressure bypass system can be set up to operate independently, directly introducing the main steam into the reheater and releasing it, so that the boiler does not need to be shut down and can always maintain a hot standby state, reducing start-up time and energy waste. When the turbine accident is resolved, the system can quickly switch back to normal operation mode to avoid production interruption and is conducive to the stability of the entire system operation.

[0013] 3. By regulating steam flow and pressure through the high-pressure bypass system, the difference between boiler steam production and turbine steam consumption can be balanced. When the turbine starts up or the load changes, the steam distribution can be flexibly adjusted to avoid boiler overpressure or insufficient steam intake to the turbine, thereby improving the turbine's adaptability to load changes and enhancing the flexibility of system operation.

[0014] 4. When the main steam pressure exceeds the set value, quickly close valves C and D, open valves A and B, and use the high-pressure bypass device to reduce pressure and discharge, quickly reduce the boiler pressure, avoid safety accidents caused by overpressure, and combine temperature and pressure sensors to monitor the bypass outlet parameters in real time to ensure that the system operates within a safe range.

[0015] 5. The high-pressure bypass system introduces excess steam into the reheater to absorb heat, which can reduce the energy loss of steam discharged into the air, improve the waste heat recovery efficiency, and reduce the unit power generation energy consumption. Attached Figure Description

[0016] Figure 1 This is a structural schematic diagram of a high-pressure bypass connection system for a vertical heat recovery coke oven waste heat boiler according to this utility model. in, Figure 1 The correspondence between the reference numerals and component names in the attached drawings is as follows: 10 Superheater, 11 Reheater, 12 Steam Turbine, 13 Connecting Pipe A, 14 Connecting Pipe B, 15 Connecting Pipe C, 16 High-Pressure Bypass Pipe, 17 High-Pressure Bypass Device, 18 Valve A, 19 Valve B, 20 Valve C, 21 Valve D, 22 Desuperheating Water Pipe, 23 Temperature Sensor, 24 Pressure Sensor. Detailed Implementation

[0017] The following are specific implementation cases and appendices. Figure 1 The present invention will be further described below, but the present invention is not limited to these embodiments.

[0018] A high-pressure bypass connection system for a vertical heat recovery coke oven waste heat boiler, such as Figure 1As shown, the system includes: a superheater 10, a reheater 11, a steam turbine 12, and a high-pressure bypass system. The steam outlet of the superheater 10 is connected to the high-pressure cylinder inlet of the steam turbine 12 via connecting pipe A13. The high-pressure cylinder outlet of the steam turbine 12 is connected to the steam inlet of the reheater 11 via connecting pipe B14. The steam outlet A of the reheater 11 is connected to the low-pressure cylinder inlet of the steam turbine 12 via connecting pipe C15, and the steam outlet B of the reheater 11 is connected to the outside air. The bypass system is located between the superheater 10 and the reheater 11. The high-pressure bypass system includes a high-pressure bypass pipe 16, a high-pressure bypass device 17, valve A18, and valve B19. The two ends of the high-pressure bypass pipe 16 are connected to connecting pipe A13 and connecting pipe B14, respectively. The high-pressure bypass device 17, valve A18, and valve B19 are respectively installed on the high-pressure bypass pipe 16. Valve C20 and valve D21 are respectively installed on connecting pipe A13 and connecting pipe B14.

[0019] Specifically, the superheater 10 includes a low-temperature superheater 10 inlet header, a low-temperature superheater 10, a low-temperature superheater 10 outlet header, a water spray desuperheater, a high-temperature superheater 10 inlet header, a high-temperature superheater 10, a high-temperature superheater 10 outlet header, and a main steam collection header.

[0020] Specifically, the reheater 11 includes a low-temperature reheater 11 inlet header, a low-temperature reheater 11, a low-temperature reheater 11 outlet header, a micro-spray desuperheater, a high-temperature reheater 11 inlet header, a high-temperature reheater 11, and a high-temperature reheater 11 outlet header.

[0021] By adopting the above structure, a high-pressure bypass system is added between the superheater 10 and the reheater 11 of the waste heat boiler. When the boiler is started up or the turbine 12 has an accident, valves C20 and D21 are closed, and valves A18 and B19 are opened. This allows the main steam to enter the high-pressure bypass device 17 through the high-pressure bypass pipe 16 for de-temperature and pressure reduction before entering the reheater 11. This ensures that there is always a steam flow in the reheater 11, avoiding local overheating, pipe wall coking, or equipment damage caused by dry burning.

[0022] When a fault occurs in turbine 12, the main steam is directly introduced into reheater 11 and released, so that the boiler does not need to be shut down and can always be kept in hot standby state, reducing start-up time and energy waste. When the fault in turbine 12 is resolved, the system can quickly switch back to normal operation mode to avoid production interruption and is conducive to the stability of the entire system operation.

[0023] The high-pressure bypass system introduces excess steam into the reheater 11 to absorb heat, which can reduce the energy loss of steam exhaust to the air, improve the waste heat recovery efficiency, and reduce the unit power generation energy consumption.

[0024] When the equipment is operating normally, the main steam of the boiler flows sequentially through the inlet header of the low-temperature superheater 10, the low-temperature superheater 10, the outlet header of the low-temperature superheater 10, the inlet header of the high-temperature superheater 10, the high-temperature superheater 10, the outlet header of the high-temperature superheater 10, and the main steam collection header. Then, it enters the high-pressure cylinder of the turbine 12 through the connecting pipe A13 to do work. The steam after doing work enters the inlet header of the low-temperature reheater 11 through the connecting pipe B14, and flows sequentially through the low-temperature reheater 11, the outlet header of the low-temperature reheater 11, the micro-spray desuperheater, the inlet header of the high-temperature reheater 11, the high-temperature reheater 11, and the outlet header of the high-temperature reheater 11. Finally, it enters the low-pressure cylinder of the turbine 12 through the connecting pipe C15 to do work.

[0025] When the boiler is started up or an accident occurs in the turbine 12, the main steam of the boiler flows sequentially through the inlet header of the low-temperature superheater 10, the low-temperature superheater 10, the outlet header of the low-temperature superheater 10, the inlet header of the high-temperature superheater 10, the high-temperature superheater 10, the outlet header of the high-temperature superheater 10, and the main steam collection header. It then enters the high-pressure bypass device 17 through the high-pressure bypass pipe 16 for desuperheating and pressure reduction. The desuperheated and pressure-reduced steam enters the inlet header of the low-temperature reheater 11 and flows sequentially through the low-temperature reheater 11, the outlet header of the low-temperature reheater 11, the micro-spray desuperheater, the inlet header of the high-temperature reheater 11, the high-temperature reheater 11, and the outlet header of the high-temperature reheater 11, and finally releases heat through the steam outlet B.

[0026] In an embodiment of this utility model, the output end of the desuperheating water pipe 22 is connected to the high-pressure bypass device 17.

[0027] The desuperheating water pipe 22 is connected to the high-pressure bypass device 17 to provide desuperheating water to the high-pressure bypass device 17. The desuperheating water is sprayed into the high-pressure bypass device 17 and mixed with steam to quickly reduce the steam temperature and prevent the inlet steam of the reheater 11 from overheating.

[0028] In an embodiment of this utility model, the input end of the desuperheating water pipe 22 is connected to the intermediate tap of the boiler feed water pump.

[0029] By connecting the inlet of the desuperheating water pipe 22 to the intermediate tap of the boiler feed water pump, the existing feed water system of the boiler can be utilized without the need for additional water pumps, thereby reducing investment costs.

[0030] Specifically, the desuperheating water used in the high-pressure bypass is the desuperheating water parameter of the intermediate tap of the boiler feed water pump.

[0031] In an embodiment of this utility model, a temperature sensor 23 and a pressure sensor 24 are provided on the high-pressure bypass pipeline 16, and the temperature sensor 23 and the pressure sensor 24 are located at the outlet of the high-pressure bypass device 17.

[0032] By regulating the steam flow and pressure through valves A18 and B19, the difference between the steam output of the boiler and the steam consumption of the turbine 12 is balanced. When the turbine 12 starts up or the load changes, the steam distribution can be flexibly adjusted to avoid boiler overpressure or insufficient steam intake of the turbine 12, thereby improving the adaptability of the turbine 12 to load changes and enhancing the flexibility of system operation.

[0033] When the main steam pressure exceeds the set value, valves C20 and D21 are quickly closed, and valves A18 and B19 are opened. The high-pressure bypass device 17 is used to reduce pressure and discharge, quickly reducing the boiler pressure and avoiding safety accidents caused by overpressure. In conjunction with temperature sensor 23 and pressure sensor 24, the bypass outlet parameters are monitored in real time to ensure that the system operates within a safe range.

[0034] Implementation process: When the equipment is operating normally, the main steam of the boiler flows sequentially through the inlet header of the low-temperature superheater 10, the low-temperature superheater 10, the outlet header of the low-temperature superheater 10, the inlet header of the high-temperature superheater 10, the high-temperature superheater 10, the outlet header of the high-temperature superheater 10, and the main steam collection header. Then, it enters the high-pressure cylinder of the turbine 12 through the connecting pipe A13 to do work. The steam after doing work enters the inlet header of the low-temperature reheater 11 through the connecting pipe B14, and flows sequentially through the low-temperature reheater 11, the outlet header of the low-temperature reheater 11, the micro-spray desuperheater, the inlet header of the high-temperature reheater 11, the high-temperature reheater 11, and the outlet header of the high-temperature reheater 11. Finally, it enters the low-pressure cylinder of the turbine 12 through the connecting pipe C15 to do work.

[0035] When the boiler is started up or an accident occurs in the turbine 12, the main steam of the boiler flows sequentially through the inlet header of the low-temperature superheater 10, the low-temperature superheater 10, the outlet header of the low-temperature superheater 10, the inlet header of the high-temperature superheater 10, the high-temperature superheater 10, the outlet header of the high-temperature superheater 10, and the main steam collection header. It then enters the high-pressure bypass device 17 through the high-pressure bypass pipe 16 for desuperheating and pressure reduction. The desuperheated and pressure-reduced steam enters the inlet header of the low-temperature reheater 11 and flows sequentially through the low-temperature reheater 11, the outlet header of the low-temperature reheater 11, the micro-spray desuperheater, the inlet header of the high-temperature reheater 11, the high-temperature reheater 11, and the outlet header of the high-temperature reheater 11, and finally releases heat through the steam outlet B.

[0036] In the description of this utility model, the term "multiple" refers to two or more. Unless otherwise explicitly defined, the terms "upper," "lower," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. The terms "connection," "installation," "fixing," etc., should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection or an indirect connection through an intermediate medium. For those skilled in the art, the specific meaning of the above terms in this utility model can be understood according to the specific circumstances.

[0037] The above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A high-pressure bypass connection system for a vertical heat recovery coke oven waste heat boiler, characterized in that, include: The system comprises a superheater, a reheater, a steam turbine, and a high-pressure bypass system. The steam outlet of the superheater is connected to the high-pressure cylinder inlet of the steam turbine via connecting pipe A. The high-pressure cylinder outlet of the steam turbine is connected to the reheater inlet via connecting pipe B. The reheater outlet A is connected to the low-pressure cylinder inlet of the steam turbine via connecting pipe C, and the reheater outlet B is connected to the outside air. The high-pressure bypass system is located between the superheater and the reheater. The high-pressure bypass system includes a high-pressure bypass pipe, a high-pressure bypass device, valve A, and valve B. Both ends of the high-pressure bypass pipe are connected to connecting pipe A and connecting pipe B, respectively. The high-pressure bypass device, valve A, and valve B are respectively installed on the high-pressure bypass pipe. Valve C and valve D are respectively installed on connecting pipe A and connecting pipe B.

2. The high-pressure bypass connection system for a vertical heat recovery coke oven waste heat boiler according to claim 1, characterized in that, The output end of the desuperheating water pipeline is connected to the high-pressure bypass device.

3. The high-pressure bypass connection system for a vertical heat recovery coke oven waste heat boiler according to claim 2, characterized in that, The inlet of the desuperheating water pipe is connected to the intermediate tap of the boiler feed water pump.

4. The high-pressure bypass connection system for a vertical heat recovery coke oven waste heat boiler according to claim 1, characterized in that, The high-pressure bypass pipeline is equipped with a temperature sensor and a pressure sensor, and the temperature sensor and pressure sensor are located at the outlet of the high-pressure bypass device.

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