An arrangement structure for back-pressure steam turbine and rear-mounted steam turbine to work together

Abstract

This utility model discloses an arrangement structure for the coordinated operation of a back-pressure steam turbine and a rear-mounted steam turbine. In this arrangement, the back-pressure steam turbine and the rear-mounted steam turbine are connected by a connecting pipeline, on which a control valve for the rear-mounted turbine is installed. A branch pipeline on the connecting pipeline connects to the user's heating system, and a heating regulating valve is installed on the branch pipeline. The output pipeline of the rear-mounted steam turbine is connected to the condenser of the rear-mounted turbine, and a steam bypass valve is installed on the output pipeline. The steam discharge pipeline of the rear-mounted steam turbine leads to the condenser of the rear-mounted turbine. This arrangement allows for the complete utilization of the exhaust steam from the back-pressure turbine. Compared to a structure with only a back-pressure steam turbine, this arrangement offers higher energy utilization of waste heat steam when user heating demand is low. Furthermore, it ensures the safe operation of the back-pressure turbine even under large fluctuations in user heating demand, while simultaneously recovering steam energy and increasing power generation.

Description

Technical Field

[0001] This utility model relates to non-variable displacement machines or engines, such as steam turbines, and specifically to an arrangement structure in which a back-pressure steam turbine and a rear-mounted steam turbine work together. Background Technology

[0002] my country's economy has shifted from a phase of high-speed growth to a phase of high-quality development, requiring the advancement of energy production, consumption, technology, and infrastructure.

[0003] A revolution in energy production is needed to build a clean, low-carbon, safe, and efficient energy system. Therefore, it is essential to promote a shift from high-carbon to high-carbon practices in all aspects of electricity production, supply, storage, sales, and consumption.

[0004] The low-carbon transition necessitates adherence to clean and low-carbon development. These "dual carbon" goals are forcing my country to build a clean, low-carbon, safe, and efficient energy system.

[0005] Advocating for a green and low-carbon lifestyle, gas-fired power, as a clean source of heat and cold, will play a role in replacing traditional coal-fired power and is an important option for replacing traditional coal-fired power in the future.

[0006] With the increasing contradiction between the high proportion of new energy access and the severe inadequacy of grid regulation capacity, gas-fired power will play an important role as a flexible power source. Gas turbines have the characteristics of fast start-up and shutdown, strong load adjustment and scaling capabilities, short construction period, and flexible site selection. They can not only perform seasonal peak shaving for the natural gas supply network, but also provide ancillary services such as peak shaving, frequency regulation, phase regulation, system backup, and black start for the power grid, alleviating power shortages, improving the stability and economy of grid operation, and ensuring the sustainable development of society and the economy.

[0007] In recent years, my country has successively constructed gas turbine generator sets for combined heat and power (CHP). To maximize heat supply, the gas turbines were configured as back-pressure turbines. However, due to changes in industrial structure and market demand for heat, electricity supply remains tight. When heat supply is insufficient, the gas turbine operates under back-pressure turbine power generation, requiring steam emissions. This results in economic losses and energy waste, as well as noise pollution affecting the lives of surrounding residents. To avoid the shutdown of back-pressure turbine generator sets and address the power shortage, the back-pressure turbines are being modified into turbine generator sets capable of both power generation and heat supply, utilizing the emitted steam to generate electricity and improve energy efficiency.

[0008] In the prior art, the patent publication number CN119435153A discloses "A saturated steam (supply) system for a supplementary steam turbine", which includes a main steam pipeline, a supplementary steam pipeline, a condenser and a steam turbine generator. This comparative technology is a conventional steam turbine technology, with poor overall power generation efficiency and low energy utilization. Utility Model Content

[0009] The purpose of this invention is to provide an arrangement structure for the coordinated operation of a back-pressure steam turbine and a rear-mounted steam turbine. This allows for connection to a new rear-mounted steam turbine generator set via pipelines, building upon an existing back-pressure steam turbine. Furthermore, by adjusting the opening of the heating regulating valve, the ratio of steam used for heating to steam used for power generation can be adjusted according to the user's heat demand. Another objective of this invention is to control the steam flow direction through valves in the pipelines, allowing for the use of steam for both heating and power generation, or purely for either purpose. Even during maintenance of the rear-mounted unit when heating is not required, the steam can be directly condensed and enter the condensate circulation pipeline, thereby improving the power generation efficiency of the back-pressure turbine while retaining its heating function.

[0010] This utility model achieves the above-mentioned technical objectives through the following technical means.

[0011] A layout structure for coordinated operation of a back-pressure steam turbine and a rear-mounted steam turbine is provided. The back-pressure steam turbine and the rear-mounted steam turbine are connected by a connecting pipeline, and a control valve for the rear-mounted steam turbine is provided on the connecting pipeline. A branch pipeline is provided on the connecting pipeline between the back-pressure steam turbine and the rear-mounted steam turbine to connect to the user's heating system. A heating regulating valve is provided on the branch pipeline. The output pipeline of the rear-mounted steam turbine is connected to the condenser of the rear-mounted steam turbine, and a steam bypass valve is provided on the output pipeline. The steam discharge pipeline of the rear-mounted steam turbine leads to the condenser of the rear-mounted steam turbine.

[0012] Furthermore, the connecting pipelines are the back pressure compressor output steam pipeline, the power generation steam pipeline, and the post-heater input steam pipeline, and the branch pipelines are heating pipelines. The heating pipelines are connected between the back pressure compressor output steam pipeline and the power generation steam pipeline, and the heating regulating valve is located in the heating pipelines.

[0013] Furthermore, the control valve for the post-processor is located on the steam inlet pipeline of the post-processor.

[0014] Preferably, the output pipeline is a condenser steam bypass, which is connected between the generator steam pipeline and the downstream turbine input steam pipeline, and the steam bypass valve is located on the condenser steam bypass.

[0015] Furthermore, when the heating regulating valve is closed, the pipeline connection between the back pressure turbine and the user heating system is disconnected.

[0016] Preferably, when the steam bypass valve is closed, the pipeline connection between the downstream condenser and the back pressure turbine is disconnected.

[0017] Preferably, when the downstream turbine control valve is closed, the pipeline connection between the downstream turbine and the back pressure turbine is disconnected.

[0018] Preferably, the opening and closing of the heating regulating valve is independent of the opening and closing of the steam bypass valve, and the opening and closing of the heating regulating valve is independent of the opening and closing of the post-heater control valve.

[0019] Preferably, the post-processor control valve and the steam bypass valve are not kept open at the same time.

[0020] Preferably, the condensate return pipeline of the post-condenser is connected to the waste heat boiler, and the waste heat boiler is connected to the back pressure turbine through a steam power generation pipeline.

[0021] This utility model has the following beneficial effects:

[0022] By connecting the steam pipeline discharged from the back-pressure turbine to the user's heating system pipeline and controlling the valve pipeline, all the exhaust steam from the back-pressure turbine can be utilized. Compared to having only a back-pressure turbine, when the user's heating demand is small, the energy utilization rate of the waste heat steam is higher. At the same time, it can ensure the safe operation of the back-pressure turbine, recover steam energy, and increase power generation even when the user's heating demand changes widely. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the arrangement structure between the back pressure machine and the rear-mounted machine of this utility model.

[0024] Figure 2 This is a schematic diagram of the overall working fluid circulation arrangement structure of this utility model.

[0025] In the diagram, 1-back pressure turbine, 2-rear turbine, 3-user heating system, 4-rear turbine condenser, 5-waste heat boiler, 6-heating regulating valve, 7-steam bypass valve, 8-rear turbine control valve, 9-back pressure turbine output steam pipeline, 10-heating pipeline, 11-power generation steam pipeline, 12-rear turbine input steam pipeline, 13-condenser steam bypass, 14-rear turbine exhaust pipeline, 15-condensate return pipeline, 16-steam power generation pipeline. Detailed Implementation

[0026] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, but the scope of protection of the present invention is not limited thereto.

[0027] Example 1:

[0028] like Figure 1 and Figure 2As shown, a back-pressure turbine and a downstream turbine are arranged to work together. The back-pressure turbine 1 and the downstream turbine 2 are connected by a connecting pipeline. A downstream turbine control valve 8 is provided on the connecting pipeline. A branch pipeline is provided on the connecting pipeline between the back-pressure turbine 1 and the downstream turbine 2 to connect to the user heating system 3. A heating regulating valve 6 is provided on the branch pipeline. The output pipeline of the downstream turbine 2 is connected to the downstream turbine condenser 4 through a condenser steam bypass 13. A steam bypass valve 7 is provided on the condenser steam bypass 13. The steam discharge pipeline of the downstream turbine 2 leads to the downstream turbine condenser 4.

[0029] The exhaust pipe of the back-pressure turbine 1 is split into two paths via a tee. One path connects to the heating regulating valve 6 to provide a heat source for users; the other path connects to the inlet of the downstream turbine 2. At the inlet, the steam is split into two paths via the tee: one path enters the downstream turbine 2, and the other path enters the downstream turbine condenser 4 via the bypass valve 7. During operation, the heating regulating valve 6 regulates the downstream pressure according to the user's steam flow to stabilize the pressure. The downstream turbine 2 uses a pressure-following mode to regulate the steam intake to drive the turbine to generate electricity. At this time, the steam is in the closed state via the bypass valve 7. When the downstream turbine 2 fails, the steam opens via the bypass valve 7, and the remaining steam after heating is discharged into the downstream turbine condenser 4 for reclaiming the working fluid, mainly condensate.

[0030] This embodiment provides an arrangement structure for the coordinated operation of a back-pressure steam turbine and a rear-mounted steam turbine. This structure is an improvement on a generator set with only a back-pressure steam turbine, integrated with the rear-mounted steam turbine to form a combined heat and power (CHP) system, improving energy utilization and power generation efficiency. The structure mainly includes a back-pressure steam turbine 1, a rear-mounted steam turbine 2, a user heating system 3, a rear-mounted condenser 4 for working fluid recovery, and a waste heat boiler 5 that converts the recovered working fluid into high-temperature, high-pressure steam. All equipment is interconnected via pipelines, and the flow of the working fluid is controlled by valves, forming a CHP system that can adjust the steam volume according to heating needs.

[0031] Specifically, steam generated by the waste heat boiler 5 is introduced into the back-pressure turbine 1 through the steam power generation pipeline 16. The steam expands and performs work inside the back-pressure turbine 1, driving the connected generator to generate electricity. Simultaneously, its pressure and temperature decrease. Due to the characteristics of the back-pressure turbine 1, the discharged steam still maintains a relatively high temperature and pressure, which can be used for heating or power generation. The waste heat steam discharged from the back-pressure turbine 1 first enters the back-pressure turbine output steam pipeline 9.

[0032] At the connection between the back-pressure unit output steam line 9 and the power generation steam line 11, a branch heating line 10 is led out. A heating regulating valve 6 is installed on the heating line 10. By adjusting the opening of the heating regulating valve 6, the amount of steam at the corresponding pressure value is controlled. The steam flows through the heating line 10 to the user's heating system 3 for heating. The remaining steam from the back-pressure unit output steam line 9 flows into the power generation steam line 11 and is then directed to the downstream unit input steam line 12.

[0033] A branch condenser steam bypass 13 is provided between the power generation steam pipeline 11 and the downstream turbine input steam pipeline 12. The condenser steam bypass 13 leads to the downstream turbine condenser 4, and a steam bypass valve 7 is provided in the condenser steam bypass 13. When the downstream turbine 2 is generating electricity normally, the steam bypass valve 7 remains closed, that is, the branch condenser steam bypass 13 is in an open state, and steam flows from the power generation steam pipeline 11 to the downstream turbine input steam pipeline 12 and enters the downstream turbine 2.

[0034] A post-turbine control valve 8 is installed in the post-turbine input steam line 12. When the post-turbine 2 is operating normally, the post-turbine control valve 8 remains open. Back-pressure steam can enter the post-turbine 2 from the post-turbine input steam line 12 to generate electricity, driving another generator or a generator coaxial with the back-pressure turbine. When the post-turbine 2 malfunctions and needs maintenance, or needs to be shut down for periodic maintenance, the post-turbine control valve 8 closes, and the steam bypass valve 7 opens. At this time, the post-turbine input steam line 12 is disconnected, and steam no longer enters the post-turbine 2. The condenser steam bypass 13 is open, and steam flows from the power generation steam line 11 to the condenser steam bypass 13, entering the post-turbine condenser 4 and directly condensing into condensate for working fluid recovery.

[0035] Under normal operating conditions, i.e., when the downstream turbine control valve 8 remains open and the steam bypass valve 7 remains closed, the exhaust steam from the downstream turbine 2 after performing work is discharged into the downstream turbine condenser 4 through the downstream turbine exhaust pipe 14. The downstream turbine condenser 4 condenses the exhaust steam into condensate, which is then transported back to the waste heat boiler 5 through the condensate return pipe 15, completing the recovery of the working fluid and the recycling of the condensate.

[0036] This layout, controlled by three valves—heating regulating valve 6, steam bypass valve 7, and post-heater control valve 8—can achieve multiple operating modes to adapt to a wide range of load variations.

[0037] If the heating demand is high, and all the steam from the back-pressure turbine 1 is used for heating, the heating regulating valve 6 can be opened to its maximum opening, while the downstream control valve 8 and the steam bypass valve 7 are closed. At this time, all the exhaust steam generated by the waste heat boiler 5 and used to drive the back-pressure turbine 1 to generate electricity via the steam power generation pipeline 16 will flow through the back-pressure turbine output steam pipeline 9 and the heating pipeline 10, and then through the heating regulating valve 6 to supply the user's heating system 3.

[0038] Example 2:

[0039] The pipeline structure in this embodiment is the same as that in Embodiment 1, but another pipeline working mode of this utility model is described in detail.

[0040] like Figure 1 and Figure 2 As shown, a back-pressure turbine and a downstream turbine are arranged to work together. The back-pressure turbine 1 and the downstream turbine 2 are connected by a connecting pipeline. A downstream turbine control valve 8 is provided on the connecting pipeline. A branch pipeline is provided on the connecting pipeline between the back-pressure turbine 1 and the downstream turbine 2 to connect to the user heating system 3. A heating regulating valve 6 is provided on the branch pipeline. The output pipeline of the downstream turbine 2 is connected to the downstream turbine condenser 4 through a condenser steam bypass 13. A steam bypass valve 7 is provided on the condenser steam bypass 13. The steam discharge pipeline of the downstream turbine 2 leads to the downstream turbine condenser 4.

[0041] The exhaust pipe of the back-pressure turbine 1 is split into two paths via a tee. One path connects to the heating regulating valve 6 to provide a heat source for users; the other path connects to the inlet of the downstream turbine 2. At the inlet, the steam is split into two paths via the tee: one path enters the downstream turbine 2, and the other path enters the downstream turbine condenser 4 via the bypass valve 7. During operation, the heating regulating valve 6 regulates the downstream pressure according to the user's steam flow to stabilize the pressure. The downstream turbine 2 uses a pressure-following mode to regulate the steam intake to drive the turbine to generate electricity. At this time, the steam is in the closed state via the bypass valve 7. When the downstream turbine 2 fails, the steam opens via the bypass valve 7, and the remaining steam after heating is discharged into the downstream turbine condenser 4 for reclaiming the working fluid, mainly condensate.

[0042] This embodiment provides an arrangement structure for the coordinated operation of a back-pressure steam turbine and a rear-mounted steam turbine. This structure is an improvement on a generator set with only a back-pressure steam turbine, integrated with the rear-mounted steam turbine to form a combined heat and power (CHP) system, improving energy utilization and power generation efficiency. The structure mainly includes a back-pressure steam turbine 1, a rear-mounted steam turbine 2, a user heating system 3, a rear-mounted condenser 4 for working fluid recovery, and a waste heat boiler 5 that converts the recovered working fluid into high-temperature, high-pressure steam. All equipment is interconnected via pipelines, and the flow of the working fluid is controlled by valves, forming a CHP system that can adjust the steam volume according to heating needs.

[0043] Specifically, steam generated by the waste heat boiler 5 is introduced into the back-pressure turbine 1 through the steam power generation pipeline 16. The steam expands and performs work inside the back-pressure turbine 1, driving the connected generator to generate electricity. Simultaneously, its pressure and temperature decrease. Due to the characteristics of the back-pressure turbine 1, the discharged steam still maintains a relatively high temperature and pressure, which can be used for heating or power generation. The waste heat steam discharged from the back-pressure turbine 1 first enters the back-pressure turbine output steam pipeline 9.

[0044] At the connection between the back-pressure unit output steam line 9 and the power generation steam line 11, a branch heating line 10 is led out. A heating regulating valve 6 is installed on the heating line 10. By adjusting the opening of the heating regulating valve 6, the amount of steam at the corresponding pressure value is controlled. The steam flows through the heating line 10 to the user's heating system 3 for heating. The remaining steam from the back-pressure unit output steam line 9 flows into the power generation steam line 11 and is then directed to the downstream unit input steam line 12.

[0045] A branch condenser steam bypass 13 is provided between the power generation steam pipeline 11 and the downstream turbine input steam pipeline 12. The condenser steam bypass 13 leads to the downstream turbine condenser 4, and a steam bypass valve 7 is provided in the condenser steam bypass 13. When the downstream turbine 2 is generating electricity normally, the steam bypass valve 7 remains closed, that is, the branch condenser steam bypass 13 is in an open state, and steam flows from the power generation steam pipeline 11 to the downstream turbine input steam pipeline 12 and enters the downstream turbine 2.

[0046] A post-turbine control valve 8 is installed in the post-turbine input steam line 12. When the post-turbine 2 is operating normally, the post-turbine control valve 8 remains open. Back-pressure steam can enter the post-turbine 2 from the post-turbine input steam line 12 to generate electricity, driving another generator or a generator coaxial with the back-pressure turbine. When the post-turbine 2 malfunctions and needs maintenance, or needs to be shut down for periodic maintenance, the post-turbine control valve 8 closes, and the steam bypass valve 7 opens. At this time, the post-turbine input steam line 12 is disconnected, and steam no longer enters the post-turbine 2. The condenser steam bypass 13 is open, and steam flows from the power generation steam line 11 to the condenser steam bypass 13, entering the post-turbine condenser 4 and directly condensing into condensate for working fluid recovery.

[0047] Under normal operating conditions, i.e., when the downstream turbine control valve 8 remains open and the steam bypass valve 7 remains closed, the exhaust steam from the downstream turbine 2 after performing work is discharged into the downstream turbine condenser 4 through the downstream turbine exhaust pipe 14. The downstream turbine condenser 4 condenses the exhaust steam into condensate, which is then transported back to the waste heat boiler 5 through the condensate return pipe 15, completing the recovery of the working fluid and the recycling of the condensate.

[0048] This layout, controlled by three valves—heating regulating valve 6, steam bypass valve 7, and post-heater control valve 8—can achieve multiple operating modes to adapt to a wide range of load variations.

[0049] If external heating is not required, the steam discharged from the back-pressure turbine 1 is used entirely for power generation. In this case, the heating regulating valve 6 is closed, the downstream turbine control valve 8 is opened, and the steam bypass valve 7 remains closed. At this time, the steam discharged from the back-pressure turbine 1 enters the power generation steam pipeline 11 through the back-pressure turbine output steam pipeline 9, and then entirely enters the downstream turbine input steam pipeline 12 to power generation in the downstream turbine 2. The exhaust steam discharged from the downstream turbine 2 after power generation is discharged through the downstream turbine exhaust pipeline 14 to the downstream turbine condenser 4 for condensation. The condensate is returned to the waste heat boiler 5 through the condensate return pipeline 15.

[0050] Example 3:

[0051] The pipeline structure in this embodiment is the same as in Embodiment 1 or 2, but another pipeline working mode of this utility model is specifically described in addition.

[0052] like Figure 1 and Figure 2 As shown, a back-pressure turbine and a downstream turbine are arranged to work together. The back-pressure turbine 1 and the downstream turbine 2 are connected by a connecting pipeline. A downstream turbine control valve 8 is provided on the connecting pipeline. A branch pipeline is provided on the connecting pipeline between the back-pressure turbine 1 and the downstream turbine 2 to connect to the user heating system 3. A heating regulating valve 6 is provided on the branch pipeline. The output pipeline of the downstream turbine 2 is connected to the downstream turbine condenser 4 through a condenser steam bypass 13. A steam bypass valve 7 is provided on the condenser steam bypass 13. The steam discharge pipeline of the downstream turbine 2 leads to the downstream turbine condenser 4.

[0053] The exhaust pipe of the back-pressure turbine 1 is split into two paths via a tee. One path connects to the heating regulating valve 6 to provide a heat source for users; the other path connects to the inlet of the downstream turbine 2. At the inlet, the steam is split into two paths via the tee: one path enters the downstream turbine 2, and the other path enters the downstream turbine condenser 4 via the bypass valve 7. During operation, the heating regulating valve 6 regulates the downstream pressure according to the user's steam flow to stabilize the pressure. The downstream turbine 2 uses a pressure-following mode to regulate the steam intake to drive the turbine to generate electricity. At this time, the steam is in the closed state via the bypass valve 7. When the downstream turbine 2 fails, the steam opens via the bypass valve 7, and the remaining steam after heating is discharged into the downstream turbine condenser 4 for reclaiming the working fluid, mainly condensate.

[0054] This embodiment provides an arrangement structure for the coordinated operation of a back-pressure steam turbine and a rear-mounted steam turbine. This structure is an improvement on a generator set with only a back-pressure steam turbine, integrated with the rear-mounted steam turbine to form a combined heat and power (CHP) system, improving energy utilization and power generation efficiency. The structure mainly includes a back-pressure steam turbine 1, a rear-mounted steam turbine 2, a user heating system 3, a rear-mounted condenser 4 for working fluid recovery, and a waste heat boiler 5 that converts the recovered working fluid into high-temperature, high-pressure steam. All equipment is interconnected via pipelines, and the flow of the working fluid is controlled by valves, forming a CHP system that can adjust the steam volume according to heating needs.

[0055] Specifically, steam generated by the waste heat boiler 5 is introduced into the back-pressure turbine 1 through the steam power generation pipeline 16. The steam expands and performs work inside the back-pressure turbine 1, driving the connected generator to generate electricity. Simultaneously, its pressure and temperature decrease. Due to the characteristics of the back-pressure turbine 1, the discharged steam still maintains a relatively high temperature and pressure, which can be used for heating or power generation. The waste heat steam discharged from the back-pressure turbine 1 first enters the back-pressure turbine output steam pipeline 9.

[0056] At the connection between the back-pressure unit output steam line 9 and the power generation steam line 11, a branch heating line 10 is led out. A heating regulating valve 6 is installed on the heating line 10. By adjusting the opening of the heating regulating valve 6, the amount of steam at the corresponding pressure value is controlled. The steam flows through the heating line 10 to the user's heating system 3 for heating. The remaining steam from the back-pressure unit output steam line 9 flows into the power generation steam line 11 and is then directed to the downstream unit input steam line 12.

[0057] A branch condenser steam bypass 13 is provided between the power generation steam pipeline 11 and the downstream turbine input steam pipeline 12. The condenser steam bypass 13 leads to the downstream turbine condenser 4, and a steam bypass valve 7 is provided in the condenser steam bypass 13. When the downstream turbine 2 is generating electricity normally, the steam bypass valve 7 remains closed, that is, the branch condenser steam bypass 13 is in an open state, and steam flows from the power generation steam pipeline 11 to the downstream turbine input steam pipeline 12 and enters the downstream turbine 2.

[0058] A post-turbine control valve 8 is installed in the post-turbine input steam line 12. When the post-turbine 2 is operating normally, the post-turbine control valve 8 remains open. Back-pressure steam can enter the post-turbine 2 from the post-turbine input steam line 12 to generate electricity, driving another generator or a generator coaxial with the back-pressure turbine. When the post-turbine 2 malfunctions and needs maintenance, or needs to be shut down for periodic maintenance, the post-turbine control valve 8 closes, and the steam bypass valve 7 opens. At this time, the post-turbine input steam line 12 is disconnected, and steam no longer enters the post-turbine 2. The condenser steam bypass 13 is open, and steam flows from the power generation steam line 11 to the condenser steam bypass 13, entering the post-turbine condenser 4 and directly condensing into condensate for working fluid recovery.

[0059] Under normal operating conditions, i.e., when the downstream turbine control valve 8 remains open and the steam bypass valve 7 remains closed, the exhaust steam from the downstream turbine 2 after performing work is discharged into the downstream turbine condenser 4 through the downstream turbine exhaust pipe 14. The downstream turbine condenser 4 condenses the exhaust steam into condensate, which is then transported back to the waste heat boiler 5 through the condensate return pipe 15, completing the recovery of the working fluid and the recycling of the condensate.

[0060] This layout, controlled by three valves—heating regulating valve 6, steam bypass valve 7, and post-heater control valve 8—can achieve multiple operating modes to adapt to a wide range of load variations.

[0061] When there is a certain heating demand, but there is still steam remaining to meet that demand, the opening of the heating regulating valve 6 is adjusted to ensure that the steam pressure entering the user's heating system 3 meets the heating demand. The downstream turbine control valve 8 remains open, while the steam bypass valve 7 remains closed. The remaining steam that does not enter the heating pipeline 10 enters the downstream turbine 2 through the downstream turbine input steam pipeline 12 to continue generating electricity. Its exhaust steam enters the downstream turbine condenser 4, condenses, and returns.

[0062] Example 4:

[0063] The pipeline structure in this embodiment is the same as that in Embodiment 1, 2, or 3. In addition, another pipeline working mode of this utility model is described.

[0064] like Figure 1 and Figure 2As shown, a back-pressure turbine and a downstream turbine are arranged to work together. The back-pressure turbine 1 and the downstream turbine 2 are connected by a connecting pipeline. A downstream turbine control valve 8 is provided on the connecting pipeline. A branch pipeline is provided on the connecting pipeline between the back-pressure turbine 1 and the downstream turbine 2 to connect to the user heating system 3. A heating regulating valve 6 is provided on the branch pipeline. The output pipeline of the downstream turbine 2 is connected to the downstream turbine condenser 4 through a condenser steam bypass 13. A steam bypass valve 7 is provided on the condenser steam bypass 13. The steam discharge pipeline of the downstream turbine 2 leads to the downstream turbine condenser 4.

[0065] The exhaust pipe of the back-pressure turbine 1 is split into two paths via a tee. One path connects to the heating regulating valve 6 to provide a heat source for users; the other path connects to the inlet of the downstream turbine 2. At the inlet, the steam is split into two paths via the tee: one path enters the downstream turbine 2, and the other path enters the downstream turbine condenser 4 via the bypass valve 7. During operation, the heating regulating valve 6 regulates the downstream pressure according to the user's steam flow to stabilize the pressure. The downstream turbine 2 uses a pressure-following mode to regulate the steam intake to drive the turbine to generate electricity. At this time, the steam is in the closed state via the bypass valve 7. When the downstream turbine 2 fails, the steam opens via the bypass valve 7, and the remaining steam after heating is discharged into the downstream turbine condenser 4 for reclaiming the working fluid, mainly condensate.

[0066] This embodiment provides an arrangement structure for the coordinated operation of a back-pressure steam turbine and a rear-mounted steam turbine. This structure is an improvement on a generator set with only a back-pressure steam turbine, integrated with the rear-mounted steam turbine to form a combined heat and power (CHP) system, improving energy utilization and power generation efficiency. The structure mainly includes a back-pressure steam turbine 1, a rear-mounted steam turbine 2, a user heating system 3, a rear-mounted condenser 4 for working fluid recovery, and a waste heat boiler 5 that converts the recovered working fluid into high-temperature, high-pressure steam. All equipment is interconnected via pipelines, and the flow of the working fluid is controlled by valves, forming a CHP system that can adjust the steam volume according to heating needs.

[0067] Specifically, steam generated by the waste heat boiler 5 is introduced into the back-pressure turbine 1 through the steam power generation pipeline 16. The steam expands and performs work inside the back-pressure turbine 1, driving the connected generator to generate electricity. Simultaneously, its pressure and temperature decrease. Due to the characteristics of the back-pressure turbine 1, the discharged steam still maintains a relatively high temperature and pressure, which can be used for heating or power generation. The waste heat steam discharged from the back-pressure turbine 1 first enters the back-pressure turbine output steam pipeline 9.

[0068] At the connection between the back-pressure unit output steam line 9 and the power generation steam line 11, a branch heating line 10 is led out. A heating regulating valve 6 is installed on the heating line 10. By adjusting the opening of the heating regulating valve 6, the amount of steam at the corresponding pressure value is controlled. The steam flows through the heating line 10 to the user's heating system 3 for heating. The remaining steam from the back-pressure unit output steam line 9 flows into the power generation steam line 11 and is then directed to the downstream unit input steam line 12.

[0069] A branch condenser steam bypass 13 is provided between the power generation steam pipeline 11 and the downstream turbine input steam pipeline 12. The condenser steam bypass 13 leads to the downstream turbine condenser 4, and a steam bypass valve 7 is provided in the condenser steam bypass 13. When the downstream turbine 2 is generating electricity normally, the steam bypass valve 7 remains closed, that is, the branch condenser steam bypass 13 is in an open state, and steam flows from the power generation steam pipeline 11 to the downstream turbine input steam pipeline 12 and enters the downstream turbine 2.

[0070] A post-turbine control valve 8 is installed in the post-turbine input steam line 12. When the post-turbine 2 is operating normally, the post-turbine control valve 8 remains open. Back-pressure steam can enter the post-turbine 2 from the post-turbine input steam line 12 to generate electricity, driving another generator or a generator coaxial with the back-pressure turbine. When the post-turbine 2 malfunctions and needs maintenance, or needs to be shut down for periodic maintenance, the post-turbine control valve 8 closes, and the steam bypass valve 7 opens. At this time, the post-turbine input steam line 12 is disconnected, and steam no longer enters the post-turbine 2. The condenser steam bypass 13 is open, and steam flows from the power generation steam line 11 to the condenser steam bypass 13, entering the post-turbine condenser 4 and directly condensing into condensate for working fluid recovery.

[0071] Under normal operating conditions, i.e., when the downstream turbine control valve 8 remains open and the steam bypass valve 7 remains closed, the exhaust steam from the downstream turbine 2 after performing work is discharged into the downstream turbine condenser 4 through the downstream turbine exhaust pipe 14. The downstream turbine condenser 4 condenses the exhaust steam into condensate, which is then transported back to the waste heat boiler 5 through the condensate return pipe 15, completing the recovery of the working fluid and the recycling of the condensate.

[0072] This layout, controlled by three valves—heating regulating valve 6, steam bypass valve 7, and post-heater control valve 8—can achieve multiple operating modes to adapt to a wide range of load variations.

[0073] When steam enters the power generation steam pipeline 11, and the downstream turbine 2 needs to be shut down for maintenance or routine inspection, the downstream turbine control valve 8 closes and the steam bypass valve 7 opens, allowing the steam in the power generation steam pipeline 11 to directly enter the downstream turbine condenser 4 for condensation. The condensate is then returned to the waste heat boiler 5 through the condensate return pipeline 15.

[0074] In summary, the piping structure provided in this embodiment, through the arrangement of the back-pressure turbine and the subsequent turbine, combined with the piping configuration and valve control, constructs a flexible thermoelectric system. It not only achieves efficient energy utilization but also effectively utilizes existing back-pressure turbine units that are usable but difficult to modify.

Claims

1. An arrangement structure for a back-pressure steam turbine and a rear-mounted steam turbine to work in coordination, characterized in that, The back-pressure turbine (1) and the rear-mounted turbine (2) are connected by a connecting pipeline. The connecting pipeline is equipped with a rear-mounted turbine control valve (8). A branch pipeline is provided on the connecting pipeline between the back-pressure turbine (1) and the rear-mounted turbine (2) to connect with the user heating system (3). A heating regulating valve (6) is provided on the branch pipeline. The output pipeline of the rear-mounted turbine (2) is connected to the rear-mounted turbine condenser (4). A steam bypass valve (7) is provided on the output pipeline. The steam discharge pipeline of the rear-mounted turbine (2) leads to the rear-mounted turbine condenser (4).

2. The arrangement structure of a back-pressure steam turbine and a rear-mounted steam turbine working in coordination according to claim 1, characterized in that, The connecting pipelines are the back pressure generator output steam pipeline (9), the power generation steam pipeline (11), and the post-heater input steam pipeline (12). The branch pipeline is the heating pipeline (10), which is connected between the back pressure generator output steam pipeline (9) and the power generation steam pipeline (11). The heating regulating valve (6) is located in the heating pipeline (10).

3. The arrangement structure for the coordinated operation of a back-pressure steam turbine and a rear-mounted steam turbine according to claim 2, characterized in that, The control valve (8) of the post-processor is located on the steam inlet pipe (12) of the post-processor.

4. The arrangement structure for the coordinated operation of a back-pressure steam turbine and a rear-mounted steam turbine according to claim 2, characterized in that, The output pipeline is a condenser steam bypass (13), which is connected between the power generation steam pipeline (11) and the downstream unit input steam pipeline (12). The steam bypass valve (7) is located on the condenser steam bypass (13).

5. The arrangement structure for the coordinated operation of a back-pressure steam turbine and a rear-mounted steam turbine according to claim 1, 2, 3, or 4, characterized in that, When the heating regulating valve (6) is closed, the pipeline connection between the back pressure turbine (1) and the user heating system (3) is disconnected.

6. The arrangement structure for the coordinated operation of a back-pressure steam turbine and a rear-mounted steam turbine according to claim 1, 2, 3, or 4, characterized in that, When the steam bypass valve (7) is closed, the pipeline connection between the downstream condenser (4) and the back pressure turbine (1) is disconnected.

7. The arrangement structure for the coordinated operation of a back-pressure steam turbine and a rear-mounted steam turbine according to claim 1, 2, 3, or 4, characterized in that, When the rear turbine control valve (8) is closed, the pipeline connection between the rear turbine (2) and the back pressure turbine (1) is disconnected.

8. The arrangement structure for the coordinated operation of a back-pressure steam turbine and a rear-mounted steam turbine according to claim 1, 2, 3, or 4, characterized in that, The opening and closing of the heating regulating valve (6) is independent of the opening and closing of the steam bypass valve (7), and the opening and closing of the heating regulating valve (6) is independent of the opening and closing of the post-heating machine control valve (8).

9. The arrangement structure for the coordinated operation of a back-pressure steam turbine and a rear-mounted steam turbine according to claim 1, 2, 3, or 4, characterized in that, The post-processor control valve (8) and the steam bypass valve (7) are not kept open at the same time.

10. The arrangement structure for coordinated operation of a back-pressure steam turbine and a rear-mounted steam turbine according to claim 1, 2, 3, or 4, characterized in that, The condensate return pipeline (15) of the post-condenser (4) is connected to the waste heat boiler (5), and the waste heat boiler (5) is connected to the back pressure turbine (1) through the steam power generation pipeline (16).

Images