Main steam deep heating water supply system
By designing the main steam depth heating water supply system, using steam pressure adjustment and temperature matching technology, the problem of difficult water supply temperature under low load is solved, the boiler flue gas temperature is increased and the depth peak-shaving capacity of the coal-fired unit is realized, and the The cascade utilization and energy-saving operation of energy.
Patent Information
- Application Number
- CN202421205018.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-05-29
- Publication Date
- 2025-02-25
- Estimated Expiration
- 2034-05-29
AI Technical Summary
When the coal-fired unit operates at low load, it is difficult to increase the water supply temperature in depth, resulting in insufficient flue gas temperature, limiting the peak-shaving capacity of the boiler, and the high-pressure heater cannot achieve energy-saving operation under low load.
A main steam depth heating water supply system was designed, and the main pressure adjustment door of the main steam depth heating water supply system was adjusted, and the steam pressure was adjusted. The temperature was matched using the No. 3 steam cooler to achieve the depth increase of the water supply temperature, and through various The pressure adjustment of the high-pressure heater achieves the need for high water outlet temperature.
It has achieved deep increase in water supply temperature under low loads and increased boiler flue gas temperature, solved the problem of difficulty in putting SCR into operation, enhanced the peak shaving capacity of coal-fired units, and achieved energy-saving operation through cascade utilization of steam.
Smart Images
Figure CN222527624U_ABST
Abstract
Description
Technical Field
[0001] The utility model belongs to the technical field of thermal power generation, and in particular relates to a main steam deep heating water supply system. Background Art
[0002] The deep peak-shaving capability of coal-fired units during the non-heating period is often constrained by the fact that the flue gas emissions of the boilers cannot meet the emission requirements. One of the main reasons is that the high-pressure feed water temperature is low under low load, resulting in low flue gas temperature.
[0003] At present, the main method of increasing the feed water temperature under low load is relatively simple. The outlet temperature of the high-pressure heater cannot be increased due to the extraction pressure of the unit. The solution is mainly to directly reduce the pressure or cool the main steam before entering a single heater, which cannot achieve a deep increase in the feed water temperature. In addition, some units have high-pressure heaters that cannot achieve energy-saving operation mode of step-by-step drainage to the deaerator under low load. The current existing technology can increase the feed water temperature under peak load regulation, but it cannot improve the operation mode of the high-pressure heater. Utility Model Content
[0004] The purpose of the utility model is to provide a main steam deep heating water supply system, which can deeply increase the water supply temperature to the required operating temperature. The water supply temperature is no longer subject to the limitation of the unit extraction pressure. The pressure adjustment can meet the pressure difference requirement of the high-pressure heater for step-by-step drainage under deep peak regulation. The use of the steam cooler can realize the deep increase of the water supply temperature while also realizing the energy-saving operation function of the cascade utilization of energy. After the water supply temperature is increased, the boiler exhaust temperature can be increased to reach or even exceed the SCR commissioning requirements, thereby realizing a deeper peak regulation capability of the coal-fired unit. At the same time, the cascade utilization of high-quality main steam is taken into consideration to maximize the operating benefits.
[0005] The utility model provides a main steam deep heating water supply system, including a boiler, a high pressure cylinder, a medium pressure cylinder, a No. 1 high pressure heater, a No. 2 high pressure heater, a No. 3 high pressure heater, a No. 1 steam cooler, a No. 3 steam cooler, a main steam deep heating water supply system isolation door, and a pressure adjustment main door;
[0006] The boiler is connected to the high-pressure cylinder through a first pipeline, and the boiler is connected to the medium-pressure cylinder through a second pipeline; the first pipeline is connected to the No. 1 steam cooler through the main steam depth heating water supply system isolation door and the pressure adjustment main door in sequence; the No. 3 high-pressure heater, the No. 2 high-pressure heater, and the No. 1 high-pressure heater are connected in sequence; the No. 1 steam cooler and the No. 1 high-pressure heater are connected to the boiler;
[0007] A steam outlet of the high-pressure cylinder is connected to the first high-pressure heater through a first valve, and another steam outlet of the high-pressure cylinder is connected to the second high-pressure heater through a third valve;
[0008] The intermediate pressure cylinder is connected to the No. 3 steam cooler through the fifth valve, and the No. 3 steam cooler is connected to the No. 3 high-pressure heater; the No. 1 high-pressure heater outlet is connected to the No. 3 steam cooler inlet; the No. 3 steam cooler outlet is connected to the No. 1 steam cooler inlet; the No. 1 steam cooler is connected to the No. 3 steam cooler through the sixth valve and the second adjustment gate; the No. 1 steam cooler is connected to the No. 1 high-pressure heater through the second valve; the No. 1 steam cooler is connected to the No. 2 high-pressure heater through the fourth valve and the first adjustment gate;
[0009] The No. 3 high-pressure heater is used to heat the high-pressure feed water of the power plant, so that the heated feed water enters the No. 2 high-pressure heater for heating and then enters the No. 1 high-pressure heater for diversion. After diversion, a part of the feed water enters the No. 3 steam cooler and then enters the No. 1 steam cooler for heating and then mixes with the other part of the feed water before entering the boiler.
[0010] Furthermore, the isolation gate of the main steam deep heating water supply system is used to open under low load, and after adjusting the pressure to the first stage extraction demand pressure through the pressure adjustment main gate, it enters the No. 3 steam cooler to heat the water supply, so that the steam after heat release maintains a superheated state and enters the thermal system through three routes, among which the first route is the superheated steam after heat release from the No. 3 steam cooler, which enters the No. 1 high-pressure heater to release heat by closing the first valve and opening the second valve; the second route is the superheated steam after heat release from the No. 3 steam cooler, which enters the No. 2 high-pressure heater to release heat after adjusting the pressure through the first adjustment gate and closing the third valve and opening the fourth valve; the third route is the superheated steam after heat release from the No. 3 steam cooler, which enters the No. 3 high-pressure heater after adjusting the pressure through the second adjustment gate and then mixes with the steam after the fifth valve to increase the outlet water temperature of the No. 3 high-pressure heater.
[0011] Through the above scheme, the main steam deep heating water supply system can ensure that the unit high pressure system drain is carried out in accordance with the step-by-step draining designed by the original thermal system during deep peak regulation, and reduce the energy waste of high pressure water supply directly entering the condenser under low load during operation adjustment. At the same time, through each pressure regulating valve, after adjusting the pressure corresponding to the different high pressure outlet water temperature requirements, the steam enters the corresponding high pressure heater to heat the water supply, so that the high pressure outlet water temperature is not subject to the influence of the unit extraction pressure, and the operation requirements of low load and high water supply temperature can be achieved, thereby increasing the flue gas temperature in the boiler and solving the problem of SCR commissioning difficulties under low load. At the same time, this system uses the use of the No. 3 steam cooler for temperature matching, further achieving the purpose of deep heating water supply temperature and the purpose of energy cascade utilization. This system can effectively solve the problems of low boiler feed water temperature and high pressure water supply water cannot be recovered to the deaerator under deep peak regulation. At the same time, through the cascade utilization of the main steam deep heating water supply system, deep heating water supply is increased, the boiler flue gas temperature is increased, and the SCR commissioning problem is solved, which can further improve the unit peak regulation capacity.
[0012] The above description is only an overview of the technical solution of the utility model. In order to more clearly understand the technical means of the utility model and implement it according to the contents of the specification, the following is a detailed description of the preferred embodiments of the utility model in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS
[0013] Figure 1 It is a structural schematic diagram of the main steam deep heating water supply system of the utility model.
[0014] Markings in the figure:
[0015] 1- boiler; 2- high-pressure cylinder; 3- medium-pressure cylinder; 4- No. 1 high-pressure heater; 5- No. 2 high-pressure heater; 6- No. 3 high-pressure heater; 7- No. 1 steam cooler; 8- No. 3 steam cooler; 9- main steam deep heating water supply system isolation door; 10- main pressure adjustment door; 11- first valve; 12- second valve; 13- third valve; 14- fourth valve; 15- first adjustment door; 16- fifth valve; 17- sixth valve; 18- second adjustment door. DETAILED DESCRIPTION
[0016] The following is a further detailed description of the specific implementation of the present invention in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.
[0017] Ginseng Figure 1As shown, this embodiment provides a main steam deep heating water supply system, including a boiler 1, a high-pressure cylinder 2, a medium-pressure cylinder 3, a No. 1 high-pressure heater 4, a No. 2 high-pressure heater 5, a No. 3 high-pressure heater 6, a No. 1 steam cooler 7, a No. 3 steam cooler 8, a main steam deep heating water supply system isolation door 9, and a pressure adjustment main door 10.
[0018] The boiler 1 is connected to the high-pressure cylinder 2 through the first pipeline, and the boiler 1 is connected to the medium-pressure cylinder 3 through the second pipeline; the first pipeline is connected to the No. 1 steam cooler 7 through the main steam deep heating water supply system isolation door 9 and the pressure adjustment main door 10 in sequence; the No. 3 high-pressure heater 6, the No. 2 high-pressure heater 5, and the No. 1 high-pressure heater 4 are connected in sequence; the No. 1 steam cooler 7 and the No. 1 high-pressure heater 4 are connected to the boiler 1.
[0019] A steam outlet of the high-pressure cylinder 2 is connected to the first high-pressure heater 4 through a first valve 11 , and another steam outlet of the high-pressure cylinder 2 is connected to the second high-pressure heater 5 through a third valve 13 .
[0020] The intermediate pressure cylinder 3 is connected to the No. 3 steam cooler 8 through the fifth valve 16, and the No. 3 steam cooler 8 is connected to the No. 3 high-pressure heater 6; the outlet of the No. 1 high-pressure heater 4 is connected to the inlet of the No. 3 steam cooler 8; the outlet of the No. 3 steam cooler 8 is connected to the inlet of the No. 1 steam cooler 7; the No. 1 steam cooler 7 is connected to the No. 3 steam cooler 8 through the sixth valve 17 and the second adjustment gate 18; the No. 1 steam cooler 7 is connected to the No. 1 high-pressure heater 4 through the second valve 12; the No. 1 steam cooler 7 is connected to the No. 2 high-pressure heater 5 through the fourth valve 14 and the first adjustment gate 15.
[0021] The steam side operation and water side operation of the main steam deep heating feed water system are described below.
[0022] Among them, the operation on the water side is: the high-pressure feed water of the power plant enters the No. 3 high-pressure heater 6 for heating, then enters the No. 2 high-pressure heater 5 for heating, and then enters the No. 1 high-pressure heater 4 for diversion. After diversion, part of the feed water enters the No. 3 steam cooler 8 and then enters the No. 1 steam cooler 7 for heating, and then mixes with the other part of the feed water before entering the boiler.
[0023] The operation of the steam side is as follows: the isolation gate 9 of the main steam deep heating water supply system is opened under low load, and the pressure is adjusted to the required pressure of the first stage of steam extraction through the main pressure adjustment gate 10, and then enters the No. 3 steam cooler 8 to heat the water supply. The steam after heat release still maintains a superheated state and enters the thermal system through three routes. The first route is the superheated steam after heat release from the No. 3 steam cooler 8, which enters the No. 1 high-pressure heater 4 to release heat through the adjustment of the first valve 11 (closed) and the second valve 12 (open); the second route is the superheated steam after heat release from the No. 3 steam cooler 8, which adjusts the pressure through the first adjustment gate 15 (the pressure adjustment is based on the outlet temperature requirement of the No. 2 high-pressure heater 5), and then enters the No. 2 high-pressure heater 5 to release heat through the adjustment of the third valve 13 (closed) and the fourth valve 14 (open); the third route is the minimum steam consumption, that is, only the superheated steam after heat release from the No. 3 steam cooler 8 is used to supplement the three-stage steam extraction pressure to increase the outlet water temperature of the No. 3 high-pressure heater 6, that is, after the pressure is adjusted through the second adjustment gate 18, it is mixed with the steam after the fifth valve 16 and enters the No. 3 high-pressure heater 6.
[0024] This system can ensure that the unit's high-pressure heating system drain is carried out in accordance with the step-by-step draining designed by the original thermal system during deep peak regulation, reducing the energy waste of high-pressure heating drain directly entering the condenser under low load under operation adjustment. At the same time, through each pressure regulating valve, after adjusting the pressure corresponding to the different high-pressure heating outlet water temperature requirements, the steam enters the corresponding high-pressure heater to heat the feed water, so that the high-pressure heating outlet water temperature is not subject to the influence of the unit's extraction pressure, and the operation requirements of low-load high-water feed temperature can be achieved, thereby increasing the flue gas temperature in the boiler and solving the problem of SCR commissioning difficulties under low load. At the same time, this system uses the use of the No. 3 steam cooler for temperature matching, further achieving the purpose of deep heating feed water temperature and the purpose of energy cascade utilization. This system can effectively solve the problems of low boiler feed water temperature and inability to recover high-pressure heating drain to the deaerator under deep peak regulation. At the same time, through the cascade utilization of the main steam deep heating feed water system, deep heating feed water is increased, the boiler flue gas temperature is increased, and the SCR commissioning problem is solved, which can further improve the unit's peak regulation capacity.
[0025] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. It should be pointed out that a person skilled in the art can make several improvements and modifications without departing from the technical principle of the present invention, and these improvements and modifications should also be regarded as within the protection scope of the present invention.
Claims
1. A main steam deep heating water supply system, characterized in that: It includes a boiler (1), a high-pressure cylinder (2), a medium-pressure cylinder (3), a No. 1 high-pressure heater (4), a No. 2 high-pressure heater (5), a No. 3 high-pressure heater (6), a No. 1 steam cooler (7), a No. 3 steam cooler (8), a main steam deep heating water supply system isolation door (9), and a pressure adjustment main door (10); The boiler (1) is connected to the high-pressure cylinder (2) via a first pipeline, and the boiler (1) is connected to the medium-pressure cylinder (3) via a second pipeline; the first pipeline is connected to the No. 1 steam cooler (7) via the main steam depth heating water supply system isolation door (9) and the pressure adjustment main door (10) in sequence; the No. 3 high-pressure heater (6), the No. 2 high-pressure heater (5), and the No. 1 high-pressure heater (4) are connected in sequence; the No. 1 steam cooler (7) and the No. 1 high-pressure heater (4) are connected to the boiler (1); A steam outlet of the high-pressure cylinder (2) is connected to the first high-pressure heater (4) through a first valve (11), and another steam outlet of the high-pressure cylinder (2) is connected to the second high-pressure heater (5) through a third valve (13); The intermediate pressure cylinder (3) is connected to the No. 3 steam cooler (8) through the fifth valve (16), and the No. 3 steam cooler (8) is connected to the No. 3 high-pressure heater (6); the outlet of the No. 1 high-pressure heater (4) is connected to the inlet of the No. 3 steam cooler (8); the outlet of the No. 3 steam cooler (8) is connected to the inlet of the No. 1 steam cooler (7); the No. 1 steam cooler (7) is connected to the No. 3 steam cooler (8) through the sixth valve (17) and the second adjustment valve (18); the No. 1 steam cooler (7) is connected to the No. 1 high-pressure heater (4) through the second valve (12); the No. 1 steam cooler (7) is connected to the No. 2 high-pressure heater (5) through the fourth valve (14) and the first adjustment valve (15); The No. 3 high-pressure heater (6) is used to heat the high-pressure feed water of the power plant, so that the heated feed water enters the No. 2 high-pressure heater (5) for heating and then enters the No. 1 high-pressure heater (4) for diversion. After diversion, a part of the feed water enters the No. 3 steam cooler (8) and then enters the No. 1 steam cooler (7) for heating and then mixes with another part of the feed water before entering the boiler (1).
2. The main steam deep heating water supply system according to claim 1 is characterized in that: The main steam deep heating water supply system isolation door (9) is used to open under low load, and after adjusting the pressure to the first stage extraction steam demand pressure through the pressure adjustment main door (10), the steam enters the No. 3 steam cooler (8) to heat the water supply, so that the steam after heat release is maintained in a superheated state and enters the thermal system through three routes, wherein the first route is the superheated steam after heat release from the No. 3 steam cooler (8), which enters the No. 1 high-pressure heater (4) to release heat by closing the first valve (11) and opening the second valve (12); the second route is the superheated steam after heat release from the No. 3 steam cooler (8), which enters the No. 2 high-pressure heater (5) to release heat by adjusting the pressure through the first adjustment door (15), closing the third valve (13), and opening the fourth valve (14); the third route is the superheated steam after heat release from the No. 3 steam cooler (8), which enters the No. 3 high-pressure heater (6) after adjusting the pressure through the second adjustment door (18), and then mixes with the steam after the fifth valve (16) to increase the outlet water temperature of the No. 3 high-pressure heater (6).