Power station drain valve inner leakage energy recovery system and operation method
By adding a sealed tank and condensate heat exchange tube to the internal leakage point of the steam trap, the problem of low sensible heat recovery rate of the internal leakage of the steam trap is solved, realizing efficient energy cascade utilization and low-cost maintenance solution.
Patent Information
- Application Number
- CN202511279925.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-09-09
- Publication Date
- 2025-12-16
AI Technical Summary
Existing technologies have failed to effectively recover the high-temperature, high-pressure liquid phase sensible heat leaking from the steam trap, resulting in energy waste and high maintenance costs.
Design a power plant steam trap internal leakage energy recovery system. By adding a sealed tank and a serpentine/spiral/U-shaped condensate heat exchange tube at the end of the steam trap header, the system utilizes low-temperature condensate to exchange heat with internal leakage steam, thereby achieving energy cascade utilization.
It significantly improves the sensible heat recovery rate, has a simple system structure, requires minimal modification, operates adaptively, requires no manual intervention, reduces maintenance labor costs, and achieves seamless integration with the regenerator system.
Smart Images
Figure CN121139947A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to a hydrophobic valve energy recovery system and operation method, in particular to a power station hydrophobic valve internal leakage energy recovery system and operation method, and belongs to the field of power generation. BACKGROUND
[0002] During the start-up and shutdown and low load stage of a thermal power generating unit, condensate water and impurities in the high-temperature and high-pressure pipelines of the main steam and reheated steam need to be discharged through a hydrophobic system to prevent water hammer and equipment damage. As a key component of the system, the action reliability of the hydrophobic valve directly affects the safety of the unit. However, due to factors such as aging of valve materials, wear of valve cores, deformation of sealing surfaces, and severe fluctuations in operating conditions, the hydrophobic valve is prone to internal leakage after long-term operation. Once internal leakage occurs, the high-temperature and high-pressure saturated water or steam will continue to be discharged into the hydrophobic expansion vessel (hereinafter referred to as "hydrophobic expansion") through the hydrophobic valve. The traditional hydrophobic expansion only relies on expansion and pressure reduction to vaporize part of the hydrophobic water, and the generated secondary steam is introduced into the deaerator or the low-pressure heater system for partial recovery. However, about 60% to 75% of the high-temperature and high-pressure liquid-phase hydrophobic water is directly discharged into the condenser or is discharged into the ditch after temperature and pressure reduction, resulting in a large amount of high-grade heat being taken away by the circulating cooling water or the environment. The existing technology mainly adopts the following ways to try to reduce the energy loss of internal leakage: a) A surface heat exchanger is added at the outlet of the hydrophobic expansion vessel to recover the latent heat of the secondary steam with condensate water, but it cannot recover the sensible heat of the liquid-phase hydrophobic water; b) The hydrophobic bypass is directly introduced into the deaerator to utilize the high-grade heat, but due to the limitation of the operating pressure of the deaerator, it is only suitable for low-pressure hydrophobic water, and it is easy to cause overpressure of the deaerator; c) The heat pump or waste heat boiler technology is used to improve the energy grade, but the system is complex, the investment is high, and it needs additional steam source to drive, which is poor in economy; d) After locating the internal leakage valve through online acoustic or temperature monitoring, the valve is manually replaced, but the number of valves is large, the location is scattered, the maintenance cycle is long, the labor intensity is high, and the hot start and stop of the unit itself brings new energy loss. In summary, the existing technology has not formed a high-efficiency, simple, and low-cost recovery scheme for the "sensible heat of high-temperature and high-pressure liquid-phase hydrophobic water" of the internal leakage of the hydrophobic valve, nor has it realized the closed-loop coupling with the regenerative system of the steam turbine, resulting in the problems of energy waste, increased unit heat consumption, and high maintenance cost, which have not been fundamentally solved. Therefore, there is an urgent need for an internal leakage energy recovery system and method that is simple in structure, easy to implement, and can be seamlessly integrated with the existing regenerative system. SUMMARY
[0003] The purpose of the present application is to solve the problem of the recovery scheme of the internal leakage of the hydrophobic valve in the existing technology, which has not realized the closed-loop coupling with the regenerative system of the steam turbine, resulting in energy waste, and to provide a power station hydrophobic valve internal leakage energy recovery system and operation method.
[0004] The present application provides the following technical solutions to solve the above problems:
[0005] The utility model provides a kind of power station drain valve inner leakage energy recovery system, it includes airtight tank, condensate water inlet pipe, condensate water outlet pipe, condensate water heat exchange pipe and multiple drain mother pipes;
[0006] Condensate water inlet pipe and condensate water outlet pipe are installed on airtight tank, condensate water heat exchange pipe is installed in airtight tank, condensate water inlet pipe outlet end is connected with condensate water outlet pipe inlet end by condensate water heat exchange pipe, multiple drain mother pipes are installed on airtight tank and communicate with airtight tank, steam flowing into airtight tank of drain mother pipe and condensate water of condensate water heat exchange pipe are heat exchanged.
[0007] Further, it also includes drain pipe, drain pipe is installed at the bottom end of airtight tank, for draining liquefied water.
[0008] Further, condensate water heat exchange pipe is one of serpentine pipe, spiral pipe or U-shaped pipe.
[0009] Further, flow regulating valve for adjusting the water inflow of condensate water inlet pipe is installed on condensate water inlet pipe.
[0010] A kind of operation method of power station drain valve inner leakage energy recovery system, the method is realized according to the following steps:
[0011] Step one: the low-temperature condensate water of regenerative system is introduced into airtight tank by condensate water inlet pipe;
[0012] Step two: the steam of inner leakage is introduced into airtight tank by multiple drain mother pipes, and the low-temperature condensate water of condensate water heat exchange pipe and introduced steam are heat exchanged;
[0013] Step three: the condensate water after heat exchange and heating is sent back to regenerative system by condensate water outlet pipe.
[0014] Further, the condensate water of condensate water inlet pipe in step one is controlled by flow valve on condensate water inlet pipe.
[0015] The technical effect compared with prior art of the present application is:
[0016] 1, the sensible heat recovery rate of the present application is greatly improved, and the existing technology depends on flash steam recovery of latent heat. The present application introduces the inner leakage steam into airtight tank and carries out forced convection heat exchange with low-temperature condensate water, and the system structure is extremely simple, and the amount of transformation is small. Traditional heat pump or waste heat boiler scheme needs to add complex dynamic equipment such as compressor and evaporator, which has high investment and large occupation. The present application only needs to add airtight tank and serpentine / spiral / U-shaped heat exchange pipe bundle at the end of existing drain mother pipe, which can be seamlessly connected with regenerative system.
[0017] 2, The application runs self-adaptive, without manual intervention, and the condensate water inlet pipe is provided with a flow regulating valve. The condensate water flow can be adjusted in real time according to the internal leakage steam quantity, the heat exchange temperature difference is stabilized, low temperature corrosion or overheating vaporization is avoided, the condensate water in the tank bottom drain pipe is automatically discharged to keep the liquid level constant, unattended continuous operation is realized, and the maintenance labor cost is significantly reduced. BRIEF DESCRIPTION OF DRAWINGS
[0018] Figure 1 It is the overall structure front view of the application. DETAILED DESCRIPTION
[0019] Combination Figure 1 In this embodiment, an internal leakage energy recovery system of a power plant steam trap is described, which comprises a sealed tank body 1, a condensate water inlet pipe 2, a condensate water outlet pipe 3, a condensate water heat exchange pipe 4 and a plurality of steam trap mother pipes 5.
[0020] The condensate water inlet pipe 2 and the condensate water outlet pipe 3 are installed on the sealed tank body 1, the condensate water heat exchange pipe 4 is installed in the sealed tank body 1, the outlet end of the condensate water inlet pipe 2 is connected with the inlet end of the condensate water outlet pipe 3 through the condensate water heat exchange pipe 4, and the plurality of steam trap mother pipes 5 are installed on the sealed tank body 1 and communicate with the sealed tank body 1. The steam flowing into the sealed tank body 1 exchanges heat with the condensate water of the condensate water heat exchange pipe 4.
[0021] The condensate water inlet pipe 2 is used to transport the condensate water of the heat recovery system to the energy recovery system, the condensate water heat exchange pipe 4 is used to exchange heat between the internal leakage steam and the condensate water, and the condensate water outlet pipe 3 is used to send the heated condensate water back to the heat recovery system. By adding the condensate water inlet pipe 2 and the condensate water heat exchange pipe 4, the originally wasted internal leakage steam heat is used to heat the condensate water of the heat recovery system, realizing energy cascade utilization. The system can be equipped with an automatic control module to monitor the internal leakage quantity in real time and adjust the condensate water flow, ensuring efficient and stable operation.
[0022] It also includes a drain pipe 6 installed at the bottom end of the sealed tank body 1 for discharging the liquefied water.
[0023] The condensate water heat exchange pipe 4 is one of a serpentine pipe, a spiral pipe or a U-shaped pipe.
[0024] A flow regulating valve for adjusting the water inflow of the condensate water inlet pipe 2 is installed on the condensate water inlet pipe 2. It is used to adapt to different internal leakage conditions.
[0025] Combination Figure 1 In this embodiment, an operating method of an internal leakage energy recovery system of a power plant steam trap is described, which is realized according to the following steps:
[0026] Step one: introducing the low-temperature condensate water of the heat recovery system into the sealed tank body 1 through the condensate water inlet pipe 2;
[0027] Step two: the inner leakage steam is passed into the closed tank 1 through the multiple water drainage mother pipes 5, and the low temperature condensate water of the condensate water heat exchange pipe 4 and the passed steam are used for heat exchange;
[0028] Step three: the heat exchanged and heated condensate water is sent back to the heat recovery system through the condensate water outlet pipe 3.
[0029] The condensate water of the condensate water inlet pipe 2 in step one is controlled through the flow valve on the condensate water inlet pipe 2.
Claims
1. A power plant drain valve internal leakage energy recovery system, characterized by: It comprises a sealed tank (1), a condensate water inlet pipe (2), a condensate water outlet pipe (3), a condensate water heat exchange pipe (4) and a plurality of steam mother pipes (5). The condensate water inlet pipe (2) and the condensate water outlet pipe (3) are installed on the sealed tank (1), the condensate water heat exchange pipe (4) is installed in the sealed tank (1), the outlet end of the condensate water inlet pipe (2) is connected with the inlet end of the condensate water outlet pipe (3) through the condensate water heat exchange pipe (4), the plurality of steam mother pipes (5) are installed on the sealed tank (1) and communicate with the sealed tank (1), and the steam flowing into the sealed tank (1) from the steam mother pipes (5) exchanges heat with the condensate water of the condensate water heat exchange pipe (4).
2. The energy recovery system for a power plant drain valve internal leakage according to claim 1, characterized in that: It further comprises a drain pipe (6) installed at the bottom end of the sealed tank (1) for draining the liquefied water.
3. The power plant drain valve internal leakage energy recovery system of claim 1, wherein: The condensate water heat exchange pipe (4) is one of a serpentine pipe, a spiral pipe or a U-shaped pipe.
4. The power plant drain valve internal leakage energy recovery system of claim 1, wherein: A flow regulating valve for regulating the water inflow of the condensate water inlet pipe (2) is installed on the condensate water inlet pipe (2).
5. The method for operating the power plant drain valve internal leakage energy recovery system according to any one of claims 1 to 4, characterized in that: The method is realized according to the following steps: Step one: introducing the low-temperature condensate water of the heat recovery system into the sealed tank (1) through the condensate water inlet pipe (2); Step two: introducing the steam of internal leakage into the sealed tank (1) through the plurality of steam mother pipes (5) and exchanging heat between the introduced steam and the low-temperature condensate water of the condensate water heat exchange pipe (4); Step three: sending the heat-exchanged condensate water back to the heat recovery system through the condensate water outlet pipe (3).
6. The method of claim 5, wherein the method further comprises: The condensate water of the condensate water inlet pipe (2) in step one is controlled through the flow valve on the condensate water inlet pipe (2).