Quaternary suitable type flue gas waste heat recovery and air intake cooling integrated combined cooling and heating system

Abstract

The application discloses a kind of seasonal adaptive flue gas waste heat recovery and air intake cooling integrated cold and heat supply system, and absorption type heat pump is connected with driving heat source loop, high-temperature output loop, low-temperature output loop;High-temperature output loop is connected with two parallelly arranged and switchable high-temperature user ends, and two high-temperature user ends are respectively: heating network, cooling tower;Low-temperature output loop is connected with two parallelly arranged and switchable low-temperature user ends;Two low-temperature user ends are respectively: waste heat boiler flue gas cooling part, gas turbine air intake cooling part;The cold and heat supply system of seasonal adaptive flue gas waste heat recovery and air intake cooling integrated of the application can flexibly switch working mode according to seasonal change, and meet the cold and heat demand of different seasons.Winter focuses on heating, summer turns to cooling, and the adaptability is strong.By setting flue gas waste heat recovery device at the tail of waste heat boiler, waste heat in flue gas is deeply recovered in heating season due to heating, and the thermal efficiency of combined cycle unit is improved.

Description

Technical Field

[0001] This invention relates to the field of absorption heat pump technology, specifically to a combined cooling and heating system that integrates seasonal flue gas waste heat recovery and intake air cooling. Background Technology

[0002] Combined cycle gas turbine units generally suffer from high flue gas temperatures, resulting in significant waste of low-temperature waste heat. Recovering this waste heat for heating in winter not only saves energy and reduces emissions but also effectively increases heating capacity. In summer, high temperatures and high gas turbine inlet temperatures negatively impact the turbine's power generation efficiency.

[0003] Currently, waste heat recovery from flue gas commonly employs direct heat exchange between the return water from the heating network and the flue gas for heating. The heat exchange equipment used is plate or shell-and-tube heat exchangers. Limited by the temperature of the return water and the temperature difference in the heat exchangers, only the sensible heat of the flue gas is recovered, with limited recovery of the waste heat. Even with deep recovery of waste heat for heating, the entire system has a single function, operating as a separate system from the gas turbine inlet cooling system in summer. This not only occupies a large space but also significantly increases investment. Therefore, a combined cycle unit system based on absorption heat pump technology has emerged for winter flue gas waste heat recovery heating and summer inlet cooling. During the heating season, it can deeply recover waste heat from the flue gas for heating. In the high-temperature summer season, the system produces chilled water to cool the gas turbine inlet, improving the overall efficiency of the gas turbine combined cycle unit. It can also be used for building refrigeration systems and external cooling, laying a technological foundation for energy conservation, emission reduction, and increased revenue for gas turbine power plants in summer.

[0004] In view of the above, it is necessary to propose a combined cooling and heating system that integrates seasonal flue gas waste heat recovery and intake air cooling to solve the above problems. Summary of the Invention

[0005] The purpose of this invention is to overcome the defects in the prior art and provide a combined cooling and heating system that integrates seasonal flue gas waste heat recovery and intake air cooling.

[0006] To achieve the above objectives, the technical solution of the present invention is as follows: a seasonally adaptable flue gas waste heat recovery and intake air cooling integrated cooling and heating system, comprising an absorption heat pump, wherein the absorption heat pump is connected to a driving heat source circuit, a high temperature output circuit, and a low temperature output circuit. The high-temperature output circuit is connected to two high-temperature user terminals that can be switched in parallel. The two high-temperature user terminals are: the heating network and the cooling tower. The low-temperature output circuit is connected to two parallel and switchable low-temperature user terminals; the two low-temperature user terminals are: the waste heat boiler flue gas cooling section and the gas turbine inlet air cooling section; When the temperature is low, the heating network and the flue gas cooling section of the waste heat boiler are put into operation, and the waste heat of the flue gas is recovered by the absorption heat pump to heat the heating network for heating. When the temperature is high, the cooling tower and the gas turbine intake cooling section are put into operation. The absorption heat pump absorbs the air temperature at the gas turbine intake and dissipates the heat through the cooling tower.

[0007] Furthermore, the absorption heat pump includes a generator, an absorber, a condenser, and an evaporator. The driving heat source circuit is connected to the generator to provide energy for the operation of the heat pump. The high-temperature output circuit is connected in sequence through the absorber and the condenser. The low-temperature output circuit is connected to the evaporator.

[0008] Furthermore, the waste heat boiler flue gas cooling section includes a partition wall heat exchanger and a first pipeline. The inlet and outlet ends of the partition wall heat exchanger are connected to the low-temperature output circuit through the first pipeline. The water inlet end of the first pipeline is equipped with a V1 shut-off valve, and the water return end is equipped with a V3 shut-off valve.

[0009] Furthermore, the gas turbine intake cooling section includes a surface cooler installed on the gas turbine intake pipe. The inlet and outlet of the surface cooler are connected to the low-temperature output circuit via a second pipeline. The upper water end of the second pipeline is equipped with a V2 shut-off valve, and the lower water end is equipped with a V4 shut-off valve. The upper water end of the second pipeline and the upper water end of the first pipeline are both connected to the upper water pipe of the low-temperature output circuit, and the lower water end of the second pipeline and the lower water end of the first pipeline are both connected to the lower water pipe of the low-temperature output circuit.

[0010] Furthermore, the heating network includes a third pipeline, the water inlet of which is connected to the water inlet of the high-temperature output circuit, and the water return end of which is connected to the water return of the high-temperature output circuit. The third pipeline is equipped with a V5 shut-off valve at the water inlet and a V7 shut-off valve at the water return end.

[0011] Furthermore, the circulating inlet and outlet of the cooling tower are connected to the high-temperature output circuit through a fourth pipeline. The upper end of the fourth pipeline is equipped with a V6 shut-off valve, and the lower end is equipped with a V8 shut-off valve. The upper ends of the third and fourth pipelines are both connected to the upper water pipe of the high-temperature output circuit, and the lower ends of the third and fourth pipelines are both connected to the lower water pipe of the high-temperature output circuit.

[0012] Furthermore, a chilled water pump is installed on the return water pipe of the low-temperature output circuit, and a cooling water circulation pump is installed on the return water end of the fourth pipeline.

[0013] Furthermore, the absorption heat pump is equipped with a built-in energy storage module based on PCM. The built-in energy storage module includes several PCM materials arranged around the evaporator. The built-in energy storage module is used to release heat from the PCM materials to supplement the energy required by the evaporator when the heat load increases or the flue gas temperature decreases.

[0014] The control method for the combined cooling and heating system integrating seasonal flue gas waste heat recovery and intake air cooling, as described above, includes the control method during winter: When using an absorption heat pump to heat the heating network in winter, open shut-off valves V1, V3, V5, and V7, while keeping shut-off valves V2, V4, V6, and V8 closed. This connects the low-temperature output circuit to the first pipeline, forming a loop, and the chilled water pump drives the intermediate water to circulate between the evaporator and the indirect heat exchanger. On the other side, the third pipeline connects to the high-temperature output circuit, forming another loop. A partition wall heat exchanger is installed inside the flue gas cooling section of the waste heat boiler. The low-temperature output circuit is connected to the first pipeline, allowing the intermediate water to exchange heat with the flue gas, thus cooling the flue gas. The intermediate water absorbs heat from the flue gas and its temperature rises. Then it enters the lithium bromide absorption heat pump evaporator to release heat and cool down. The return water of the heating network enters the absorber and condenser of the lithium bromide absorption heat pump in sequence to be heated and then returns to the heating network pipeline. The heated return water of the heating network then enters the first station to continue to be heated or is directly supplied as heating network water via the heating network circulation pump.

[0015] Furthermore, this includes control measures during the summer: When using an absorption heat pump to cool the gas turbine intake air in summer, open valves V2, V4, V6, and V8, while keeping valves V1, V3, V5, and V7 closed. This connects the low-temperature output circuit to the second pipeline, forming a loop, and the chilled water pump drives the chilled water to circulate between the evaporator and the surface cooler. On the other side, the fourth pipeline connects to the high-temperature output circuit, forming another loop. The air entering the gas turbine is cooled by chilled water. The chilled water absorbs heat from the air and rises in temperature after passing through a surface cooler. It then enters a lithium bromide absorption heat pump evaporator to release heat and cool down. The chilled water is then pumped into the evaporator by the first water pump. The chilled water is circulated in this way to cool the air entering the gas turbine. Cooling water flows from the cooling tower through a cooling circulating water pump into the absorber and condenser of the lithium bromide absorption heat pump, carrying away heat and raising its temperature. Finally, it returns to the cooling tower, and the cooled circulating water then enters the lithium bromide absorption heat pump again.

[0016] The advantages and beneficial effects of this invention are as follows: 1. The seasonally adaptable combined cooling and heating system integrating flue gas waste heat recovery and intake air cooling can flexibly switch its working mode according to seasonal changes to meet the heating and cooling needs of different seasons. It focuses on heating in winter and cooling in summer, demonstrating strong adaptability. By installing a flue gas waste heat recovery device at the tail end of the waste heat boiler, the waste heat in the flue gas is deeply recovered for heating during the heating season, improving the thermal efficiency of the combined cycle unit; a surface cooler is installed at the gas turbine inlet to cool the air; coupled with the combined cycle unit, a new flue gas waste heat recovery heating and gas turbine intake air cooling process is constructed. Based on absorption heat pump technology, the combined cycle unit's winter flue gas waste heat recovery heating and summer intake air cooling system improves the overall efficiency of the gas-fired steam combined cycle unit, achieving both better economic and environmental benefits.

[0017] 2. Multi-stage utilization based on different flue gas heat quality: Low-grade flue gas waste heat is recovered for heating, reducing heating operating costs and increasing heating revenue; flue gas temperature is lowered below the dew point, deeply recovering sensible and latent heat from the flue gas, while condensate simultaneously absorbs acidic gases such as SO2 and NOx from the flue gas, improving local environmental quality. During summer intake cooling, the gas turbine intake temperature can be reduced to around 10°C or even lower, increasing the gas turbine intake volume and improving the overall efficiency of the gas-steam combined cycle unit. Excess cooling capacity from the lithium bromide heat pump can also be used in on-site building cooling systems and external cooling, laying a technical foundation for energy conservation, emission reduction, and increased revenue for gas turbine power plants in summer.

[0018] 3. During winter heating, deep heat recovery from flue gas can lower the flue gas temperature to around 30℃ or even lower, fully recovering the latent and sensible heat in the flue gas for heating and improving the thermal efficiency of the combined cycle unit. The low-resistance, new type of indirect-flow flue gas / water heat exchanger is embedded inside the flue, resulting in low resistance and saving external space.

[0019] 4. The energy storage unit of phase change material (PCM) is directly embedded into the absorption heat pump to form an integrated solution. This design not only reduces the equipment's footprint but also improves the system's response speed and operational flexibility. This integration allows for more efficient utilization of flue gas waste heat and rapid release of stored energy during peak demand periods, ensuring stable system operation. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the combined cooling and heating system of the present invention, which integrates seasonal flue gas waste heat recovery and intake air cooling. In the diagram: 1. Absorption heat pump; 2. Drive heat source circuit; 3. High-temperature output circuit; 4. Low-temperature output circuit; 5. Heating network; 6. Cooling tower; 7. Waste heat boiler flue gas cooling section; 8. Gas turbine inlet cooling section; 9. Generator; 10. Absorber; 11. Condenser; 12. Evaporator; 13. Indirect heat exchanger; 14. First pipeline; 15. V1 shut-off valve; 16. V3 shut-off valve; 17. Surface cooler; 18. Second pipeline; 19. V2 shut-off valve; 20. V4 shut-off valve; 21. Third pipeline; 22. V5 shut-off valve; 23. V7 shut-off valve; 24. Fourth pipeline; 25. V6 shut-off valve; 26. V8 shut-off valve; 27. Chilled water pump; 28. Cooling water circulation pump; 29. ​​Built-in energy storage module. Detailed Implementation

[0021] The specific embodiments of the present invention will be further described below with reference to the accompanying drawings and examples. The following examples are only used to more clearly illustrate the technical solutions of the present invention and should not be construed as limiting the scope of protection of the present invention.

[0022] A seasonally adaptable combined cooling and heating system integrating flue gas waste heat recovery and intake air cooling, such as Figure 1 As shown, the system includes an absorption heat pump 1, which is connected to a driving heat source circuit 2, a high-temperature output circuit 3, and a low-temperature output circuit 4. This system uses a lithium bromide absorption heat pump 1. Specifically, the absorption heat pump 1 includes a generator 9, an absorber 10, a condenser 11, and an evaporator 12. The driving heat source circuit 2 is connected to the generator 9 to provide energy for the operation of the heat pump. In this embodiment, the driving heat source is steam.

[0023] The high-temperature output circuit 3 is connected in sequence through the absorber 10 and the condenser 11; the low-temperature output circuit 4 is connected to the evaporator 12.

[0024] The high-temperature output circuit 3 is connected to two high-temperature user terminals that are configured in parallel and can be switched. The two high-temperature user terminals are: heating network 5 and cooling tower 6. Specifically, the heating network 5 includes a third pipe 21, the water inlet of the third pipe 21 is connected to the water inlet of the high temperature output circuit 3, and the return water inlet is connected to the return water inlet of the high temperature output circuit 3. The third pipe 21 is equipped with a V5 shut-off valve 22 at the water inlet and a V7 shut-off valve 23 at the return water inlet.

[0025] Furthermore, the circulating inlet and outlet of the cooling tower 6 are connected to the high-temperature output circuit 3 via a fourth pipe 24. The upper end of the fourth pipe 24 is equipped with a V6 shut-off valve 25, and the lower end with a V8 shut-off valve 26. The upper ends of both the third pipe 21 and the fourth pipe 24 are connected to the upper water pipe of the high-temperature output circuit 3, and the lower ends are connected to the lower water pipe of the high-temperature output circuit 3. The upper water pipe of the high-temperature output circuit 3 is connected to V5 shut-off valve 22 and V6 shut-off valve 25 via a tee. Switching between V5 and V6 shut-off valves controls the water flow into the heating network 5 or the cooling tower 6. Similarly, the lower water pipe of the high-temperature output circuit 3 is connected to V7 and V8 shut-off valves 23 via a tee, controlling the flow direction of the two branch lines. A cooling water circulation pump 28 is installed on the lower end of the fourth pipe 24. An independent circulation pump is also installed in the heating network 5.

[0026] The low-temperature output circuit 4 is connected to two low-temperature user terminals that are configured in parallel and can be switched; the two low-temperature user terminals are: the waste heat boiler flue gas cooling section 7 and the gas turbine inlet cooling section 8.

[0027] Specifically, the waste heat boiler flue gas cooling section 7 includes a partition wall heat exchanger 13 and a first pipeline 14. The inlet and outlet ends of the partition wall heat exchanger 13 are connected to the low temperature output circuit 4 through the first pipeline 14. The water inlet end of the first pipeline 14 is equipped with a V1 shut-off valve 15, and the water return end is equipped with a V3 shut-off valve 16.

[0028] Furthermore, the gas turbine intake cooling section 8 includes a surface cooler 17 installed on the gas turbine intake pipe. The inlet and outlet of the surface cooler 17 are connected to the low-temperature output circuit 4 through a second pipe 18. The upper water end of the second pipe 18 is equipped with a V2 shut-off valve 19, and the lower water end is equipped with a V4 shut-off valve 20. The upper water end of the second pipe 18 and the upper water end of the first pipe 14 are both connected to the upper water pipe of the low-temperature output circuit 4, and the lower water end of the second pipe 18 and the lower water end of the first pipe 14 are both connected to the lower water pipe of the low-temperature output circuit 4. Both the inlet and outlet water pipes of the low-temperature output circuit 4 are equipped with tee pipes. The tee pipes at the inlet water pipe end are connected to the V1 shut-off valve 15 and the V2 shut-off valve 19, respectively, and the tee pipes at the outlet water pipe end are connected to the V3 shut-off valve 16 and the V4 shut-off valve 20, respectively. A chilled water pump 27 is installed on the outlet water pipe of the low-temperature output circuit 4. By switching the shut-off valves, the low-temperature output circuit 4 can form a circuit with the first pipeline 14 and the second pipeline 18, respectively. When it forms a circuit with the first pipeline 14, it is used in winter, and the heat pump transfers the heat from the low-grade heat source of the waste heat boiler exhaust gas to the high-temperature output circuit 3 for heating the heating network 5. When it forms a circuit with the second pipeline 18, it is used in summer, and the absorption heat pump 1 is used to cool the intake air of the gas turbine.

[0029] When the temperature is low, the heating network 5 and the waste heat boiler flue gas cooling section 7 are put into operation, and the absorption heat pump 1 is used to recover the waste heat of the flue gas to heat the heating network 5 for heating. When the temperature is high, cooling tower 6 and gas turbine intake cooling section 8 are put into operation. Absorption heat pump 1 absorbs the air temperature at the gas turbine intake and dissipates the heat through cooling tower 6.

[0030] Specifically, during winter heating, the first water pump sends the hot water from the low-resistance, novel indirect-flow flue gas / water heat exchanger (indirect-flow heat exchanger 13) in the waste heat boiler's exhaust flue to the evaporator 12. After cooling, the hot water returns to the low-resistance, novel indirect-flow flue gas / water heat exchanger. The return water from the heating network 5 sequentially enters the absorber 10 and condenser 11, and after being heated, flows back into the heating network 5. Driven steam enters the generator 9 to release heat, and the condensate returns to the power plant's condensate recovery system.

[0031] During summer intake cooling, chilled water from evaporator 12 is pumped into the surface cooler via the first water pump to cool the gas turbine intake air. The chilled water absorbs heat and returns to evaporator 12, where it is cooled before returning to surface cooler 17. Cooling water then enters absorber 10 and condenser 11, carrying away heat, and is further cooled by cooling tower 6. Driven steam enters generator 9 to release heat, and the condensate returns to the power plant's condensate recovery system.

[0032] The performance of the absorption heat pump 1 depends on the stability of the input heat. When the temperature of the heat source (such as waste heat from flue gas) is unstable or the heat load suddenly increases, the system efficiency may decrease or fail to meet the demand. PCM can store excess heat when the heat load is low and release it when the heat load is high, thus smoothing out heat load fluctuations. As an improvement, the absorption heat pump 1 includes a built-in PCM-based energy storage module 29. The built-in energy storage module 29 includes several PCM materials arranged around the evaporator 12. The built-in energy storage module 29 is used to release heat from the PCM materials to supplement the energy required by the evaporator 12 when the heat load increases or the flue gas temperature decreases.

[0033] Specifically, one or more layers of PCM plates or PCM capsules are arranged around the evaporator 12 of the absorption heat pump 1. These PCM materials can absorb heat and undergo a phase change (solid to liquid) at low temperatures, and vice versa (liquid to solid) when needed, releasing the previously stored heat. The PCM materials are arranged in a wrapping form around the outer periphery of the evaporator 12, similar to wrapping insulation materials, but in this embodiment, the purpose is to store and release energy, not just reduce heat loss. When the heat pump recovers heat from the flue gas, some of the heat is transferred to the PCM materials for storage; when the heat load increases or the flue gas temperature drops and is insufficient to meet immediate demand, the PCM materials begin to release heat, supplementing the energy required by the evaporator 12 and ensuring that the refrigerant can continue to evaporate effectively. PCM materials with high latent heat value, good thermal conductivity and chemical stability, and suitable for the specific application temperature range are selected. In addition, the heat exchange efficiency can be optimized by adjusting the shape and distribution of the PCM, for example, by using microencapsulation technology or manufacturing a honeycomb structure to increase the contact area.

[0034] The absorption heat pump 1 incorporates an energy storage module. When the system is running, if the evaporator 12 generates cooling (i.e., refrigerant evaporation absorbs heat), the surrounding PCM material condenses due to the temperature drop, storing the cooling energy. Conversely, during off-peak hours or when additional cooling is needed, the PCM material melts and releases the previously stored energy. This configuration enhances the system's energy efficiency because it stores energy when electricity costs are low or renewable energy supplies are plentiful, and uses this stored energy during peak hours or when demand suddenly increases. Simultaneously, it helps balance the load on the heat pump system, reducing reliance on immediate energy supply.

[0035] The control method for the combined cooling and heating system integrating seasonal flue gas waste heat recovery and intake air cooling, as described above, includes the control method during winter: When the absorption heat pump 1 is used to heat the heating network 5 in winter, the V1 shut-off valve 15, V3 shut-off valve 16, V5 shut-off valve 22, and V7 shut-off valve 23 are opened, while the V2 shut-off valve 19, V4 shut-off valve 20, V6 shut-off valve 25, and V8 shut-off valve 26 are kept closed; the low-temperature output circuit 4 is connected to the first pipeline 14 to form a circuit, and the intermediate water is driven by the chilled water pump 27 to circulate between the evaporator 12 and the partition heat exchanger 13; on the other side, the third pipeline 21 is connected to the high-temperature output circuit 3 to form a circuit; A partition wall heat exchanger 13 is installed in the flue gas cooling section 7 of the waste heat boiler. The low temperature output circuit 4 is connected to the first pipeline 14, so that the intermediate water exchanges heat with the flue gas to cool the flue gas. The intermediate water absorbs heat from the flue gas and its temperature rises. Then it enters the evaporator 12 of the lithium bromide absorption heat pump 1 to release heat and cool down. The return water of the heating network 5 enters the absorber 10 and condenser 11 of the lithium bromide absorption heat pump 1 in sequence to be heated and then returns to the heating network 5 pipeline. The heated return water of the heating network enters the first station to continue to be heated or is directly supplied as heating network water through the heating network circulation pump.

[0036] During winter heating, shut-off valves 23 (V1, V3, V5, V7) are open, and shut-off valves 26 (V2, V4, V6, V8) are closed. The operating system includes a low-resistance novel indirect-connection flue gas / water heat exchanger and a lithium bromide absorption heat pump 1. The lithium bromide absorption heat pump 1 includes a generator 9, a condenser 11, an evaporator 12, and an absorber 10. The low-resistance novel indirect-connection flue gas / water heat exchanger is installed in the flue between the waste heat boiler area and the main chimney. The flue gas is cooled by exchanging heat with intermediate water. The intermediate water absorbs heat from the flue gas and its temperature rises. It then enters the evaporator 12 of the lithium bromide absorption heat pump 1 to release heat and cool down. The water is then pumped into the low-resistance novel indirect-connection flue gas / water heat exchanger. The intermediate water is continuously recycled to recover waste heat from the flue gas.

[0037] The steam driving the lithium bromide absorption heat pump 1 enters the generator 9 to release heat, and the condensate is returned to the power plant's condensate recovery system.

[0038] The return water from the heating network enters the absorber 10 and condenser 11 of the lithium bromide absorption heat pump 1 sequentially from the heating network pipeline for heating and temperature rise, and finally returns to the heating network pipeline. The heated return water then enters the first station for further temperature rise or is directly supplied as heating network water via the heating network circulation pump.

[0039] Furthermore, this includes control measures during the summer: When using the absorption heat pump 1 to cool the gas turbine intake air in summer, the V2 shut-off valve 19, V4 shut-off valve 20, V6 shut-off valve 25, and V8 shut-off valve 26 are opened, while the V1 shut-off valve 15, V3 shut-off valve 16, V5 shut-off valve 22, and V7 shut-off valve 23 are kept closed; this connects the low-temperature output circuit 4 with the second pipeline 18 to form a loop, and the chilled water pump 27 drives the chilled water to circulate between the evaporator 12 and the surface cooler 17; on the other side, the fourth pipeline 24 connects with the high-temperature output circuit 3 to form a loop. The air entering the gas turbine is cooled by chilled water. The chilled water absorbs heat from the air and rises in temperature after passing through the surface cooler 17. It then enters the evaporator 12 of the lithium bromide absorption heat pump 1 to release heat and cool down. The chilled water is then sent to the evaporator 12 by the first water pump. The chilled water is circulated in this way to cool the intake air of the gas turbine. Cooling water flows from cooling tower 6 through a cooling circulating water pump into the absorber 10 and condenser 11 of lithium bromide absorption heat pump 1, carrying away heat and raising its temperature. Finally, it returns to cooling tower 6, and the cooled circulating water then enters lithium bromide absorption heat pump 1.

[0040] During summer cooling, shut-off valves 26 (V2, V4, V6, V8) are open, and shut-off valves 23 (V1, V3, V5, V7) are closed. The operating system includes a surface cooler 17 and a lithium bromide absorption heat pump 1. The lithium bromide absorption heat pump 1 includes a generator 9, a condenser 11, an evaporator 12, and an absorber 10. A surface cooler 17 is installed at the gas turbine inlet. Chilled water is used to cool the air entering the gas turbine. The chilled water absorbs heat from the air and its temperature rises. It then enters the evaporator 12 of the lithium bromide absorption heat pump 1 to release heat and cool down. The chilled water is then pumped into the evaporator 12. The chilled water is continuously circulated to cool the air.

[0041] The steam driving the lithium bromide absorption heat pump 1 enters the generator 9 to release heat, and the condensate is returned to the power plant's condensate recovery system.

[0042] Cooling circulating water flows from cooling tower 6 through a cooling circulating water pump into the absorber 10 and condenser 11 of lithium bromide absorption heat pump 12 to remove heat, and finally returns to cooling tower 6. The cooled cooling circulating water then enters lithium bromide absorption heat pump 1.

[0043] Working principle: During winter heating, the waste heat from the flue gas is transferred to the intermediate water through a low-resistance novel partitioned flue gas / water heat exchanger. The intermediate water serves as the waste heat source for the lithium bromide absorption heat pump 1. Driven by high-grade steam, the lithium bromide absorption heat pump 1 transfers the low-grade waste heat to the medium-temperature heat source (heating network 5 water), thereby realizing the recovery of waste heat from the flue gas for heating.

[0044] During summer cooling, chilled water exchanges heat with the air entering the gas turbine through the surface cooler 17, transferring the heat from the air to the chilled water. The chilled water then enters the evaporator 12 of the lithium bromide absorption heat pump 1 for further cooling. Driven by steam, the lithium bromide absorption heat pump 1 transfers the heat from the air and the steam to the circulating cooling water, which is then cooled by the cooling tower 6.

[0045] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A seasonally adaptable combined cooling and heating system integrating flue gas waste heat recovery and intake air cooling, characterized in that, It includes an absorption heat pump (1), which is connected to a driving heat source circuit (2), a high temperature output circuit (3), and a low temperature output circuit (4). The high-temperature output circuit (3) is connected to two high-temperature user terminals that are set in parallel and can be switched. The two high-temperature user terminals are: heating network (5) and cooling tower (6). The low-temperature output circuit (4) is connected to two low-temperature user terminals that are configured in parallel and can be switched; the two low-temperature user terminals are: the waste heat boiler flue gas cooling section (7) and the gas turbine inlet cooling section (8). When the temperature is low, the heating network (5) and the waste heat boiler flue gas cooling section (7) are put into operation, and the waste heat of the flue gas is recovered by the absorption heat pump (1) to heat the heating network (5) for heating. When the temperature is high, the cooling tower (6) and the gas turbine intake cooling section (8) are put into operation. The absorption heat pump (1) absorbs the air temperature at the gas turbine intake and dissipates the heat through the cooling tower (6).

2. The combined cooling and heating system integrating seasonal flue gas waste heat recovery and intake air cooling as described in claim 1, characterized in that, The absorption heat pump (1) includes a generator (9), an absorber (10), a condenser (11), and an evaporator (12). The driving heat source circuit (2) is connected to the generator (9) to provide energy for the operation of the heat pump. The high temperature output circuit (3) is connected in sequence through the absorber (10) and the condenser (11). The low temperature output circuit (4) is connected to the evaporator (12).

3. The combined cooling and heating system integrating seasonal flue gas waste heat recovery and intake air cooling as described in claim 2, characterized in that, The waste heat boiler flue gas cooling section (7) includes a partition wall heat exchanger (13) and a first pipeline (14). The inlet and outlet ends of the partition wall heat exchanger (13) are connected to the low temperature output circuit (4) through the first pipeline (14). The water inlet end of the first pipeline (14) is equipped with a V1 shut-off valve (15) and the water return end is equipped with a V3 shut-off valve (16).

4. The seasonally adaptable combined cooling and heating system integrating flue gas waste heat recovery and intake air cooling according to claim 3, characterized in that, The gas turbine intake cooling section (8) includes a surface cooler (17) installed on the gas turbine intake pipe. The inlet and outlet of the surface cooler (17) are connected to the low-temperature output circuit (4) through a second pipe (18). The upper end of the second pipe (18) is equipped with a V2 shut-off valve (19), and the lower end is equipped with a V4 shut-off valve (20). The upper end of the second pipe (18) and the upper end of the first pipe (14) are both connected to the upper water pipe of the low-temperature output circuit (4). The lower end of the second pipe (18) and the lower end of the first pipe (14) are both connected to the lower water pipe of the low-temperature output circuit (4).

5. The seasonally adaptable flue gas waste heat recovery and intake air cooling integrated combined cooling and heating system according to claim 4, characterized in that, The heating network (5) includes a third pipeline (21). The water inlet of the third pipeline (21) is connected to the water inlet of the high temperature output circuit (3), and the return water inlet is connected to the return water inlet of the high temperature output circuit (3). The third pipeline (21) is equipped with a V5 shut-off valve (22) at the water inlet and a V7 shut-off valve (23) at the return water inlet.

6. The seasonally adaptable flue gas waste heat recovery and intake air cooling integrated combined cooling and heating system according to claim 5, characterized in that, The circulating inlet and outlet of the cooling tower (6) are connected to the high-temperature output circuit (3) through the fourth pipe (24). The upper end of the fourth pipe (24) is equipped with a V6 shut-off valve (25), and the lower end is equipped with a V8 shut-off valve (26). The upper ends of the third pipe (21) and the fourth pipe (24) are both connected to the upper water pipe of the high-temperature output circuit (3). The lower ends of the third pipe (21) and the fourth pipe (24) are both connected to the lower water pipe of the high-temperature output circuit (3).

7. The seasonally adaptable combined cooling and heating system integrating flue gas waste heat recovery and intake air cooling according to claim 6, characterized in that, The return water pipe of the low temperature output circuit (4) is equipped with a chilled water pump (27), and the return water end of the fourth pipeline (24) is equipped with a cooling water circulation pump (28).

8. The seasonally adaptable combined cooling and heating system integrating flue gas waste heat recovery and intake air cooling according to claim 7, characterized in that, The absorption heat pump (1) is equipped with a PCM-based built-in energy storage module (29), which includes a number of PCM materials arranged around the evaporator (12). The built-in energy storage module (29) is used to release heat from the PCM materials to supplement the energy required by the evaporator (12) when the heat load increases or the flue gas temperature decreases.

9. The control method for the combined cooling and heating system integrating seasonal flue gas waste heat recovery and intake air cooling as described in claim 1, characterized in that, Including control methods during winter: When the absorption heat pump (1) is used to heat the heating network (5) in winter, the V1 shut-off valve (15), V3 shut-off valve (16), V5 shut-off valve (22), and V7 shut-off valve (23) are opened, while the V2 shut-off valve (19), V4 shut-off valve (20), V6 shut-off valve (25), and V8 shut-off valve (26) are kept closed; the low-temperature output circuit (4) is connected to the first pipeline (14) to form a circuit, and the intermediate water is driven by the chilled water pump (27) to circulate between the evaporator (12) and the partition heat exchanger (13); on the other side, the third pipeline (21) is connected to the high-temperature output circuit (3) to form a circuit; A partition wall heat exchanger (13) is installed in the flue gas cooling section (7) of the waste heat boiler. The low temperature output circuit (4) is connected to the first pipeline (14) so ​​that the intermediate water exchanges heat with the flue gas to cool down the flue gas. The intermediate water absorbs heat from the flue gas and its temperature rises. Then it enters the evaporator (12) of the lithium bromide absorption heat pump (1) to release heat and cool down. The return water of the heating network (5) enters the absorber (10) and condenser (11) of the lithium bromide absorption heat pump (1) in sequence to be heated and heated up. Finally, it returns to the heating network (5) pipeline. The heated return water of the heating network enters the first station to continue to heat up or is directly supplied as heating network water through the heating network circulation pump.

10. The control method for the combined cooling and heating system integrating seasonal flue gas waste heat recovery and intake air cooling according to claim 9, characterized in that, Including control measures during the summer: When using an absorption heat pump (1) to cool the gas turbine intake air in summer, open the V2 shut-off valve (19), V4 shut-off valve (20), V6 shut-off valve (25), and V8 shut-off valve (26), while keeping the V1 shut-off valve (15), V3 shut-off valve (16), V5 shut-off valve (22), and V7 shut-off valve (23) closed; connect the low-temperature output circuit (4) with the second pipeline (18) to form a circuit, and drive the chilled water pump (27) to circulate the chilled water between the evaporator (12) and the surface cooler (17); on the other side, connect the fourth pipeline (24) with the high-temperature output circuit (3) to form a circuit; The air entering the gas turbine is cooled by chilled water. The chilled water absorbs heat from the air and rises in temperature after passing through the surface cooler (17). It then enters the lithium bromide absorption heat pump (1) evaporator (12) to release heat and cool down. The chilled water is then pumped into the evaporator (12) by the first water pump. The chilled water is circulated in this way to cool the air entering the gas turbine. Cooling water enters the absorber (10) and condenser (11) of the lithium bromide absorption heat pump (1) from the cooling tower (6) through the cooling circulating water pump, carries away heat and increases temperature, and finally returns to the cooling tower (6). The cooled circulating water then enters the lithium bromide absorption heat pump (1).

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