Steam turbine outlet dead steam waste heat recovery system

Abstract

The utility model discloses a steam turbine outlet dead steam waste heat recovery system, and relates to the technical field of steam turbine energy recycling. Comprising a steam turbine, a generator, a condenser, an absorption heat pump and a heat supply network system, the generator is connected with the power output end of the steam turbine, the condenser is communicated with a dead steam outlet of the steam turbine, and a heat source inlet of the absorption heat pump is communicated with a steam extraction opening of the steam turbine through a steam extraction pipeline; a closed circulating water path is arranged between the absorption type heat pump and the condenser, circulating water in the closed circulating water path can flow between the condenser and the absorption type heat pump in a bidirectional circulating mode, the heat supply network system is connected with the absorption type heat pump, and the heat supply network system directly heats heat supply network water through high-temperature dead steam in the absorption type heat pump. The heat supply network water in the heat supply network system can also indirectly exchange heat with the circulating water through the absorption heat pump. The steam turbine outlet dead steam waste heat recovery device can achieve efficient recovery and reutilization of steam turbine outlet dead steam waste heat, and reduces thermal pollution to the environment.

Description

Technical Field

[0001] This utility model relates to the field of steam turbine energy recovery and utilization technology, specifically a steam turbine outlet exhaust steam waste heat recovery system. Background Technology

[0002] In industrial production processes involving steam turbine operation, such as thermal power generation, the exhaust steam from the turbine represents the largest energy loss. Currently, existing steam turbine exhaust steam treatment systems typically employ open-loop circulating water systems. However, during the operation of these systems, water continuously evaporates and is released into the air, resulting in significant exhaust steam loss and causing thermal pollution to the environment.

[0003] Therefore, there is an urgent need for a system that can efficiently recover the energy of exhaust steam at the turbine outlet while overcoming the aforementioned problems. Utility Model Content

[0004] The purpose of this invention is to provide a waste heat recovery system for exhaust steam at the turbine outlet to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, this utility model provides the following technical solution: a waste heat recovery system for steam turbine outlet steam, comprising a steam turbine, a generator, a condenser, an absorption heat pump, and a heat network system. The generator is connected to the power output end of the steam turbine, the condenser is connected to the waste steam outlet of the steam turbine, the heat source inlet of the absorption heat pump is connected to the steam extraction port of the steam turbine via an extraction pipe, a closed-loop circulating water circuit is provided between the absorption heat pump and the condenser, the circulating water in the closed-loop circulating water circuit can circulate bidirectionally between the condenser and the absorption heat pump, the condenser transfers the heat released during condensation to the absorption heat pump through the closed-loop circulating water circuit, the heat network system is connected to the absorption heat pump, and the heat network system uses the high-temperature waste steam from the absorption heat pump to directly heat the heat network water. The heat network water in the heat network system can also indirectly exchange heat with the circulating water within the absorption heat pump.

[0006] Based on the above technical features, in this invention, a portion of the turbine outlet exhaust steam enters an absorption heat pump as a direct heat source for heating the heating network water. In the absorption heat pump, this portion of exhaust steam can be directly used to heat the heating network water. The other portion of the outlet exhaust steam enters a condenser for condensation. A closed-loop circulating water system fully absorbs the heat released during the condensation of this portion of exhaust steam. The circulating water in the closed-loop system absorbs this heat in the condenser, and its temperature rises. The heated circulating water then exchanges heat with the heating network water in the absorption heat pump, indirectly transferring the heat released during the condensation process to the heating network water. Therefore, this invention can achieve efficient recovery and reuse of waste heat from the turbine outlet exhaust steam, reducing thermal pollution to the environment and playing a significant role in improving the environment and promoting green and sustainable development.

[0007] Preferably, in this technical solution, the closed-loop circulating water circuit includes a closed-loop circulating water pipe and a closed-loop circulating water pump. The closed-loop circulating water pipe is divided into an inlet pipe and a return pipe. The closed-loop circulating water pump is installed on the inlet pipe to promote the circulation of circulating water in the closed-loop circulating water circuit. One end of the inlet pipe is connected to the first water inlet of the condenser, and the other end is connected to the first water inlet of the absorption heat pump. The condenser transfers the heat released during condensation to the absorption heat pump through the inlet pipe. One end of the return pipe is connected to the second water inlet of the absorption heat pump, and the other end is connected to the second water inlet of the condenser. The absorption heat pump transfers the heat-exchanged circulating water to the condenser through the return pipe.

[0008] Based on the above technical features, the closed-loop circulating water circuit composed of the inlet pipe, the recovery pipe and the closed-loop circulating water pump can ensure that the circulating water in the condenser can quickly reach the absorption heat pump after the temperature rises. At the same time, it can also ensure that the circulating water in the absorption heat pump can quickly reach the condenser for reheating, so as to realize the efficient utilization of the heat released by the condenser condensation.

[0009] In this technical solution, preferably, the temperature difference between the circulating water in the inlet pipe and the return pipe is controlled between 25℃ and 35℃.

[0010] Based on the above technical features, the appropriate temperature difference between the circulating water in the inlet and outlet water pipes can ensure that the condenser and absorption heat pump operate under optimal conditions, thereby improving heat exchange efficiency and meeting the requirements for efficient recovery and utilization of waste heat from exhaust steam.

[0011] In this technical solution, preferably, the circulating water in the closed-loop circulating water circuit is demineralized water or soft water.

[0012] Based on the above technical features, using demineralized water or soft water for circulating water can effectively reduce scale formation, thereby protecting equipment and improving heat exchange efficiency.

[0013] Preferably, in this technical solution, the waste heat recovery system for the turbine outlet also includes a boiler, which is connected to the condensate outlet of the condenser. A high-temperature steam pipeline connected to the turbine's waste steam inlet is provided between the boiler and the turbine, and the superheated steam produced in the boiler can be transported to the turbine through the high-temperature steam pipeline. More preferably, a feedwater pump is provided between the boiler and the condensate outlet of the condenser, and the condensate generated by the condenser is pumped to the boiler through the feedwater pump.

[0014] Based on the above technical features, the feedwater pump can transport the condensate in the condenser to the boiler, which heats the condensate to generate steam with a certain pressure and temperature. The steam enters the turbine to continue doing work. The turbine, condenser, feedwater pump, boiler and high-temperature steam pipeline form a closed-loop circulating water system. Compared with the open-loop circulating water treatment system in the prior art, the circulating water in the closed-loop circulating water system can circulate in closed pipelines and does not come into direct contact with the outside air. The water quality is relatively stable, and the water volume in the system can remain basically unchanged.

[0015] In this technical solution, preferably, the turbine outlet exhaust steam waste heat recovery system also includes a heating network water supply pump, which can pump heated heating network water to the heating network system.

[0016] Preferably, in this technical solution, the extraction pressure in the extraction pipe is greater than 0.3 MPa.

[0017] Based on the above technical features, the efficiency and safe operation of the turbine outlet waste heat recovery system can be guaranteed, and the efficient recovery and utilization of waste heat can be effectively realized. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the waste heat recovery system of the turbine outlet steam in an embodiment of this utility model.

[0019] In the diagram: 1. Steam turbine; 11. Exhaust steam outlet; 12. Extraction steam inlet; 13. Extraction steam pipeline; 14. High-temperature steam pipeline; 15. Exhaust steam inlet; 2. Generator; 3. Condenser; 31. First water inlet; 32. Second water inlet; 33. Condensate outlet; 4. Absorption heat pump; 41. Heat source inlet; 42. First water inlet; 43. Second water inlet; 5. Closed-loop circulating water system; 51. Closed-loop circulating water pipeline; 511. Inlet pipeline; 512. Return pipeline; 52. Closed-loop circulating water pump; 6. Heating network system; 61. Heating network water supply pump; 7. Boiler; 8. Feedwater pump. Detailed Implementation

[0020] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0021] It should be noted that in the description of this utility model, the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They 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. Therefore, they should not be construed as limitations on this utility model.

[0022] Furthermore, it should be understood that, for ease of description, the dimensions of the various components shown in the accompanying drawings are not drawn to actual scale.

[0023] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined or described in one figure, it will not need to be discussed or described in detail in the description of the subsequent figures.

[0024] like Figure 1 As shown, this utility model provides a technical solution: a waste heat recovery system for steam turbine outlet steam, including a steam turbine 1, a generator 2 connected to the power output end of the steam turbine 1, a condenser 3 connected to the waste steam outlet 11 of the steam turbine 1, an absorption heat pump 4, and a heat network system 6.

[0025] Specifically, the heat source inlet 41 of the absorption heat pump 4 is connected to the extraction steam port 12 of the steam turbine 1 via the extraction steam pipe 13. A closed-loop circulating water circuit 5 is provided between the absorption heat pump 4 and the condenser 3. The circulating water in the closed-loop circulating water circuit 5 can circulate bidirectionally between the condenser 3 and the absorption heat pump 4. The condenser 3 transfers the heat released during condensation to the absorption heat pump 4 through the closed-loop circulating water circuit 5. The heating network system 6 is connected to the absorption heat pump 4. The heating network system 6 uses the high-temperature exhaust steam in the absorption heat pump 4 to directly heat the heating network water. The heating network water in the heating network system 6 can also indirectly exchange heat with the circulating water in the absorption heat pump 4.

[0026] In this invention, a portion of the exhaust steam from turbine 1 enters the absorption heat pump 4 as a direct heat source. In the absorption heat pump 4, this portion of exhaust steam can be directly used to heat the heating network water. The other portion of the exhaust steam enters the condenser 3 for condensation. The closed-loop circulating water system 5 fully absorbs the heat released during the condensation of this portion of exhaust steam. The circulating water in the closed-loop circulating water system 5 increases in temperature after absorbing the heat from this portion of exhaust steam in the condenser 3. The heated circulating water then exchanges heat with the heating network water in the absorption heat pump 4, thus indirectly transferring the heat released during the condensation process of the condenser 3 to the heating network water. Therefore, the turbine exhaust steam waste heat recovery system can achieve efficient recovery and reuse of the exhaust steam from turbine 1, reducing thermal pollution to the environment and playing a significant role in improving the environment and promoting green and sustainable development.

[0027] like Figure 1 As shown, the closed-loop circulating water system 5 includes a closed-loop circulating water pipe 51 and a closed-loop circulating water pump 52. The closed-loop circulating water pipe 51 is divided into an inlet pipe 511 and a return pipe 512. The closed-loop circulating water pump 52 is a pump with appropriate flow rate and head, and is installed on the inlet pipe 511 to promote the stable circulation of circulating water in the closed-loop circulating water system 5. One end of the inlet pipe 511 is connected to the first water inlet 31 of the condenser 3, and the other end is connected to the first water inlet 42 of the absorption heat pump 4. The condenser 3 transfers the heat released during condensation to the absorption heat pump 4 through the inlet pipe 511, that is, the circulating water with increased temperature is transported to the absorption heat pump 4 through the inlet pipe 511. One end of the return water pipe 512 is connected to the second water inlet 43 of the absorption heat pump 4, and the other end is connected to the second water inlet 32 ​​of the condenser 3. The absorption heat pump 4 transmits the heat-exchanged circulating water to the condenser 3 through the return water pipe. That is, the circulating water after heat exchange and cooling is transported to the condenser 3 for reheating through the return water pipe 512.

[0028] Furthermore, the temperature difference between the circulating water in the inlet pipe 511 and the return pipe 512 is controlled between 25°C and 35°C. This appropriate temperature difference ensures that the condenser 3 and the absorption heat pump 4 operate under optimal conditions, thereby improving heat exchange efficiency and meeting the requirements for efficient recovery and utilization of waste heat from exhaust steam. Preferably, in a specific embodiment of this invention, the temperature difference between the circulating water in the inlet pipe 511 and the return pipe 512 is controlled at 30°C. Simultaneously, the temperature of the circulating water flowing into the return pipe 512 after heat exchange and cooling by the absorption heat pump 4 is controlled below 28°C.

[0029] The circulating water in the closed-loop circulating water circuit 5 is demineralized water or soft water, which can effectively reduce the formation of scale in the closed-loop circulating water circuit 5, so as to protect the equipment and improve the heat exchange efficiency.

[0030] like Figure 1 As shown, the turbine outlet waste heat recovery system also includes a boiler 7, which is connected to the condensate outlet 33 of the condenser 3. A high-temperature steam pipeline 14 is provided between the boiler 7 and the turbine 1, connecting to the waste steam inlet 15 of the turbine 1. The superheated steam produced in the boiler 7 can be transported to the turbine 1 through the high-temperature steam pipeline 14. In the turbine 1, the energy of the steam is converted into mechanical energy to drive the generator 2 (specifically, the thermal energy of the superheated steam in the turbine 1 is first converted into kinetic energy, and then the kinetic energy is converted into mechanical energy to drive the generator 2). After being generated by the generator 2, the temperature and pressure of the waste steam decrease before it enters the condenser 3. A feedwater pump 8 is provided between the boiler 7 and the condensate outlet 33 of the condenser 3. The condensate produced by the condenser 3, after being treated by the deaerator, can be pumped back to the boiler 7 by the feedwater pump 8.

[0031] The feedwater pump 8 can transport the condensate in the condenser 3 to the boiler 7. The boiler 7 heats the condensate to produce steam with a certain pressure and temperature. The steam enters the turbine 1 to continue doing work. The turbine 1, condenser 3, feedwater pump 8, boiler 7 and high-temperature steam pipeline 14 form a closed-loop circulating water system. Compared with the open-loop circulating water treatment system in the prior art, the circulating water in the closed-loop circulating water system can circulate in the closed pipeline and does not come into direct contact with the outside air. Therefore, the water quality is relatively stable and the water volume in the system can remain basically unchanged.

[0032] like Figure 1 As shown, the turbine outlet exhaust steam waste heat recovery system also includes a heating network water supply pump 61, which can pump heated heating network water to the heating network system 6 at a suitable flow rate and pressure according to the needs of the heating network system 6.

[0033] The extraction steam pressure in extraction pipe 13 is greater than 0.3 MPa to ensure the efficient and safe operation of the exhaust steam waste heat recovery system at the turbine 1 outlet, and to effectively realize the efficient recovery and utilization of exhaust steam waste heat.

[0034] The turbine outlet waste heat recovery system of this utility model can also monitor and control key parameters such as the flow rate and temperature of condenser 3, circulating water, and heating network water in real time, ensuring the coordinated and efficient operation of all equipment in the system, guaranteeing the stability and reliability of the entire waste heat recovery system, reducing the probability of equipment failure, and lowering maintenance costs. Furthermore, the turbine outlet waste heat recovery system provided by this utility model has a wide range of applications, suitable for various industrial fields involving the operation of turbine 1, such as thermal power generation and combined heat and power (CHP). It can be flexibly adjusted according to different operating conditions and needs, possessing good versatility and adaptability, and can be widely promoted and applied in the industry, bringing significant social and economic benefits.

[0035] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A waste heat recovery system for steam turbine outlet steam, comprising a steam turbine (1), a generator (2) connected to the power output end of the steam turbine (1), and a condenser (3) connected to the waste steam outlet (11) of the steam turbine (1), characterized in that, Also includes: An absorption heat pump (4) is provided, the heat source inlet (41) of the absorption heat pump (4) is connected to the steam extraction port (12) of the steam turbine (1) through the steam extraction pipe (13), a closed-loop circulating water circuit (5) is provided between the absorption heat pump (4) and the condenser (3), the circulating water in the closed-loop circulating water circuit (5) can circulate bidirectionally between the condenser (3) and the absorption heat pump (4), the condenser (3) transfers the heat released in condensation to the absorption heat pump (4) through the closed-loop circulating water circuit (5); The heat network system (6) is connected to the absorption heat pump (4). The heat network system (6) uses the high-temperature exhaust steam in the absorption heat pump (4) to directly heat the heat network water. The heat network water in the heat network system (6) can also indirectly exchange heat with the circulating water in the absorption heat pump (4).

2. The turbine outlet waste heat recovery system according to claim 1, characterized in that, The closed-loop circulating water system (5) includes a closed-loop circulating water pipe (51) and a closed-loop circulating water pump (52). The closed-loop circulating water pipe (51) is divided into an inlet pipe (511) and a return pipe (512). The closed-loop circulating water pump (52) is installed on the inlet pipe (511) to promote the circulation of circulating water in the closed-loop circulating water system (5). One end of the water inlet pipe (511) is connected to the first water inlet (31) of the condenser (3), and the other end is connected to the first water inlet (42) of the absorption heat pump (4). The condenser (3) transfers the heat released during condensation to the absorption heat pump (4) through the water inlet pipe (511). One end of the return water pipe (512) is connected to the second water inlet (43) of the absorption heat pump (4), and the other end is connected to the second water inlet (32) of the condenser (3). The absorption heat pump (4) transmits the heat-exchanged circulating water to the condenser (3) through the return water pipe (512).

3. The turbine outlet exhaust heat recovery system according to claim 2, characterized in that, The temperature difference between the circulating water in the inlet pipe (511) and the return pipe (512) is controlled between 25℃ and 35℃.

4. The turbine outlet exhaust heat recovery system according to any one of claims 1 to 3, characterized in that, The circulating water in the closed-loop circulating water system (5) is either demineralized water or soft water.

5. The turbine outlet exhaust heat recovery system according to claim 1, characterized in that, It also includes a boiler (7), which is connected to the condensate outlet (33) of the condenser (3). A high-temperature steam pipe (14) is provided between the boiler (7) and the turbine (1) and is connected to the exhaust steam inlet (15) of the turbine (1). The superheated steam produced in the boiler (7) can be transported to the turbine (1) through the high-temperature steam pipe (14).

6. The turbine outlet exhaust heat recovery system according to claim 5, characterized in that, A feedwater pump (8) is provided between the boiler (7) and the condensate outlet (33) of the condenser (3), and the condensate generated by the condenser (3) is pumped to the boiler (7) through the feedwater pump (8).

7. The turbine outlet exhaust heat recovery system according to claim 1, characterized in that, It also includes a heating network water supply pump (61), which can pump heated heating network water to the heating network system (6).

8. The turbine outlet exhaust heat recovery system according to claim 1, characterized in that, The extraction pressure in the extraction pipe (13) is greater than 0.3 MPa.

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