A reheater steam attemper system

Abstract

The utility model discloses a reheater steam attemperator system, including steam turbine high pressure cylinder, low temperature reheater, steam attemperator, high temperature reheater and steam turbine middle pressure cylinder, steam turbine high pressure cylinder is communicated with low temperature reheater, steam attemperator, high temperature reheater, steam turbine middle pressure cylinder in proper order through main steam pipeline, the gas outlet of steam turbine high pressure cylinder is communicated with steam attemperator through side steam pipeline, is equipped with flow regulating valve in the middle part of side steam pipeline, and the low temperature steam of steam turbine high pressure cylinder is formed into medium temperature steam after entering low temperature reheater and heating, and the medium temperature steam enters steam attemperator and mixes with the low temperature steam directly discharged by steam turbine high pressure cylinder and reduces temperature, and after reducing temperature, enters high temperature reheater and heats to become high temperature steam, and the high temperature steam is transported to steam turbine middle pressure cylinder and is used, improves the economy of unit operation, strengthens the security reliability heat efficiency of system, and reduces the installation operation maintenance cost.

Description

Technical Field

[0001] This utility model relates to the field of boiler energy saving and efficiency improvement technology, and in particular to a reheater steam desuperheater system. Background Technology

[0002] Thermal power plants generate electricity through boilers, turbines, and generators. The boiler produces high-pressure main steam and high-pressure reheat steam, which then enter the turbine to perform work and output mechanical energy. The parameters of the high-pressure main steam and high-pressure reheat steam need to be controlled. The desuperheater, as a key component for the high-pressure main steam and high-pressure reheat steam, is crucial for the safe, stable, and efficient operation of a thermal power plant. Traditional reheater spray desuperheater systems inject high-pressure water into the reheater system to control steam temperature. This method suffers from safety, reliability, and low thermal efficiency issues, and also has high installation costs. Utility Model Content

[0003] The purpose of this invention is to provide a reheater steam desuperheater system to solve the problems mentioned in the background art.

[0004] To achieve the above objectives, this utility model provides the following technical solution: a reheater steam desuperheater system, comprising a turbine high-pressure cylinder, a low-temperature reheater, a steam desuperheater, a high-temperature reheater, and a turbine intermediate-pressure cylinder. The turbine high-pressure cylinder is sequentially connected to the low-temperature reheater, the steam desuperheater, the high-temperature reheater, and the turbine intermediate-pressure cylinder via a main steam pipeline. The outlet of the turbine high-pressure cylinder is connected to the steam desuperheater via a bypass steam pipeline, and a flow regulating valve is provided in the middle of the bypass steam pipeline.

[0005] Preferably, high-pressure steam is input into the inlet of the high-pressure cylinder of the steam turbine.

[0006] Preferably, the flow regulating valve is a pneumatic regulating valve.

[0007] Preferably, the high-temperature reheater and the low-temperature reheater are connected by a flue gas duct, with high-temperature flue gas entering through the flue gas inlet of the high-temperature reheater and low-temperature flue gas exiting through the flue gas outlet of the low-temperature reheater.

[0008] Preferably, the side steam pipe in the middle of the steam desuperheater is located inside the main steam pipe, and the side steam pipe is located at one end of the main steam pipe in a corner shape, with a frustum at the corner end.

[0009] Preferably, the outer circular wall of the frustum is provided with a plurality of exhaust hole groups along the length direction.

[0010] Preferably, the exhaust hole group is an exhaust hole arranged in a ring on the outer circular wall of a frustum.

[0011] The beneficial effects of this utility model are:

[0012] 1. High-pressure main steam is delivered to the high-pressure cylinder of the steam turbine via an external system. The low-temperature steam discharged from the high-pressure cylinder enters the low-temperature reheater and is heated to form medium-temperature steam. The medium-temperature steam enters the steam desuperheater and mixes with the low-temperature steam directly discharged from the high-pressure cylinder of the steam turbine for desuperheating. After desuperheating, it enters the high-temperature reheater for heating to become high-temperature steam. The high-temperature steam is then delivered to the intermediate-pressure cylinder of the steam turbine for use. Compared with the traditional reheater spray water desuperheating system, this avoids the phenomenon of steam carrying water due to improper use, enhances the safety, reliability, and thermal efficiency of the system, and reduces installation, operation, and maintenance costs. For gas-fired steam combined cycle units, it can also improve the economic operation of the unit.

[0013] 2. The steam flow rate is regulated by the flow regulating valve to control the inlet and outlet steam temperatures of the high-temperature reheater, preventing the output steam temperature from being too high and protecting downstream equipment from damage due to overheating.

[0014] 3. By opening several exhaust holes in the outer circular wall of the truncated cone of the steam pipe, the low-temperature steam after being throttled by the flow regulating valve is mixed with the medium-temperature steam output from the low-temperature reheater in a multi-spiral airflow, so as to fully and efficiently mix the medium-temperature steam and the low-temperature steam.

[0015] 4. By simplifying the system structure, the system layout and installation are facilitated, reducing the cost of use and maintenance. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the structure of an embodiment of the present utility model;

[0017] Figure 2 This is a schematic diagram of the main steam pipe and the bypass steam pipe in the steam desuperheater of this utility model embodiment;

[0018] Figure 3 The embodiments of this utility model are attached. Figure 2 A cross-sectional view along the AA direction.

[0019] In the diagram: 1. High-pressure cylinder of steam turbine; 2. Intermediate-pressure cylinder of steam turbine; 3. Flow regulating valve; 4. Steam desuperheater; 5. Low-temperature reheater; 6. High-temperature reheater; 7. Main steam pipe; 8. Bypass steam pipe; 81. Frustum; 82. Exhaust port. 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] Please see Figures 1 to 3 This utility model provides a reheater steam desuperheater system, including a turbine high-pressure cylinder 1, a low-temperature reheater 5, a steam desuperheater 4, a high-temperature reheater 6, and a turbine intermediate-pressure cylinder 2. The turbine high-pressure cylinder 1 is connected sequentially to the low-temperature reheater 5, the steam desuperheater 4, the high-temperature reheater 6, and the turbine intermediate-pressure cylinder 2 via a main steam pipe 7. The outlet of the turbine high-pressure cylinder 1 is connected to the steam desuperheater 4 via a bypass steam pipe 8. A flow regulating valve 3 is provided in the middle of the bypass steam pipe 8 to regulate the flow of high-pressure main steam. The steam is sent to the high-pressure cylinder 1 of the steam turbine, where the low-temperature steam discharged from the high-pressure cylinder 1 enters the low-temperature reheater 5 and is heated to become medium-temperature steam. The medium-temperature steam enters the steam desuperheater 4 and mixes with the low-temperature steam directly discharged from the high-pressure cylinder 1 of the steam turbine for desuperheating. After desuperheating, it enters the high-temperature reheater 6 and is heated to become high-temperature steam. The high-temperature steam is then delivered to the intermediate-pressure cylinder 2 of the steam turbine for use. Compared with the traditional reheater water spray desuperheater system that requires water to be sprayed into the steam passage, this system is safer and avoids water carryover in the steam due to improper use, which could affect the safe operation of the high-temperature reheater 6.

[0022] Specifically, the steam pipes in the middle of the low-temperature reheater 5 and the high-temperature reheater 6 are embedded in the middle of the corresponding flue gas pipes. The temperature of the flue gas entering the middle of the low-temperature reheater 5 is higher than the temperature of the steam entering the low-temperature reheater 5, which facilitates the low-temperature steam to absorb heat from the flue gas to form medium-temperature flue gas.

[0023] Specifically, by installing at least one flow regulating valve 3 in the adjacent steam pipe 8, the low-temperature steam discharged from the high-pressure cylinder 1 of the turbine flows through the flow regulating valve 3 and then enters the steam desuperheater 4 after being throttled. This allows the medium-temperature steam flowing through the low-temperature reheater 5 to mix and cool with the low-temperature steam directly discharged from the high-pressure cylinder 1 of the turbine in the middle of the steam desuperheater 4. This steam mixing and cooling method replaces the traditional water spray desuperheater, avoiding the injection of water into the steam passage and preventing impurities in the water from being introduced into the steam passage. This also prevents scaling on the high-temperature reheater 6 from occurring over a long period of time. For some units, the total heat absorption of the reheater and superheater is fixed. Water spray desuperheating will increase the heat absorption of the reheater and decrease the heat absorption of the superheater, resulting in a reduction in the flow rate of the high-pressure main steam and a decrease in the overall operating economy of the unit.

[0024] Specifically, high-pressure steam is input into the inlet of the high-pressure cylinder 1 of the steam turbine. The high-pressure main steam comes from the steam generated by the external boiler. By connecting the high-pressure cylinder 1 of the steam turbine to the steam pipeline of the external boiler, the high-pressure steam is output to the high-pressure cylinder 1 of the steam turbine for use. After the high-pressure steam does work through the high-pressure cylinder 1 of the steam turbine, it becomes medium-pressure low-temperature steam and flows to the low-temperature reheater 5.

[0025] Specifically, the flow regulating valve 3 is a pneumatic regulating valve. Pneumatic regulating valves have the advantages of sensitive regulation and fast response speed, which can control the flow rate more quickly and accurately. Since pneumatic regulating valves are existing technology, they will not be described in detail.

[0026] Specifically, the high-temperature reheater 6 and the low-temperature reheater 5 are connected by a flue gas duct. High-temperature flue gas is input into the flue gas inlet of the high-temperature reheater 6, and low-temperature flue gas is output from the flue gas outlet of the low-temperature reheater 5. The flue gas ducts of the high-temperature reheater 6 and the low-temperature reheater 5 are connected through the flue gas duct, so that the high-temperature flue gas input into the high-temperature reheater 6 heats the mixed steam output from the steam desuperheater 4, and then flows into the low-temperature reheater 5 through the flue gas duct to heat the low-temperature steam output from the high-pressure cylinder 1 of the steam turbine. This realizes the cascade utilization of the heat of the flue gas and improves the thermal efficiency of the equipment.

[0027] Specifically, the side steam pipe 8 in the middle of the steam desuperheater 4 is located inside the main steam pipe 7. The side steam pipe 8 is located at one end of the main steam pipe 7 in a corner shape. A frustum 81 is provided at the corner end. The low-temperature steam output from the high-pressure cylinder 1 of the steam turbine is guided along the main steam pipe 7 and the side steam pipe 8 to the middle of the steam desuperheater 4 for steam mixing and cooling treatment.

[0028] Specifically, the outer circular wall of the frustum 81 is provided with a number of exhaust holes 82 along the length direction. The low-temperature steam flowing through the flow regulating valve 3 is mixed with the medium-temperature steam output from the low-temperature reheater 5 through the number of exhaust holes 82, thereby improving the steam mixing effect.

[0029] Specifically, the exhaust port 82 group consists of several exhaust ports 82 arranged in a ring on the outer circular wall of the frustum 81. Through the several exhaust ports 82 arranged in a ring on the outer circular wall of the frustum 81 of the adjacent steam pipe 8, the low-temperature steam after being throttled by the flow regulating valve 3 is mixed with the medium-temperature steam output from the low-temperature reheater 5 in a multi-stream spiral airflow, so as to fully and efficiently mix the medium-temperature steam and the low-temperature steam.

[0030] The working principle of this utility model is as follows: In use, high-pressure main steam is delivered to the high-pressure cylinder 1 of the steam turbine through an external system. The low-temperature steam discharged from the high-pressure cylinder 1 of the steam turbine enters the low-temperature reheater 5 and is heated to form medium-temperature steam. The medium-temperature steam enters the steam desuperheater 4 and mixes and desuperheats with the low-temperature steam directly discharged from the high-pressure cylinder 1 of the steam turbine. After desuperheating, it enters the high-temperature reheater 6 and is heated to become high-temperature steam. The high-temperature steam is delivered to the intermediate-pressure cylinder 2 of the steam turbine for use. Compared with the traditional reheater water spray desuperheater system that requires water to be sprayed into the steam passage, this system is safer and avoids water carryover in the steam due to improper use, which would affect the safe operation of the high-temperature reheater 6.

[0031] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions or improvements made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A reheater steam desuperheater system, characterized in that; It includes a high-pressure cylinder (1) of a steam turbine, a low-temperature reheater (5), a steam desuperheater (4), a high-temperature reheater (6), and a medium-pressure cylinder (2) of a steam turbine. The high-pressure cylinder (1) of the steam turbine is connected to the low-temperature reheater (5), the steam desuperheater (4), the high-temperature reheater (6), and the medium-pressure cylinder (2) of the steam turbine in sequence through the main steam pipe (7). The outlet of the high-pressure cylinder (1) of the steam turbine is connected to the steam desuperheater (4) through the side steam pipe (8). The side steam pipe (8) is provided with a flow regulating valve (3) in the middle.

2. The reheater steam desuperheater system according to claim 1, characterized in that, High-pressure steam is input into the inlet of the high-pressure cylinder (1) of the steam turbine.

3. The reheater steam desuperheater system according to claim 1, characterized in that, The flow regulating valve (3) is a pneumatic regulating valve.

4. A reheater steam desuperheater system according to claim 1, characterized in that, The high-temperature reheater (6) and the low-temperature reheater (5) are connected by a flue gas pipe. High-temperature flue gas is input into the flue gas inlet of the high-temperature reheater (6), and low-temperature flue gas is output from the flue gas outlet of the low-temperature reheater (5).

5. A reheater steam desuperheater system according to claim 1, characterized in that, The side steam pipe (8) in the middle of the steam desuperheater (4) is located inside the main steam pipe (7). The side steam pipe (8) is located at one end of the main steam pipe (7) in a corner shape, and a frustum (81) is provided at the corner end.

6. A reheater steam desuperheater system according to claim 5, characterized in that, The outer circular wall of the frustum (81) is provided with a number of exhaust hole groups along the length direction.

7. A reheater steam desuperheater system according to claim 6, characterized in that, The exhaust hole group is an exhaust hole (82) provided in the outer circular wall of the frustum (81).

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