Dead steam heat recovery system and control method thereof, electronic equipment and storage medium

Abstract

The invention discloses a dead steam heat recovery system and a control method thereof, electronic equipment and a storage medium. The control method comprises the steps that the vacuum degree of the steam exhaust end of the heat recovery condenser and the temperature of an outlet of the water end of the heat recovery condenser are obtained; according to the vacuum degree of the steam exhaust end of the heat recovery condenser and the temperature of an outlet of the water end of the heat recovery condenser, the opening degree of an adjusting valve between the steam exhaust main pipe and the heat recovery condenser is adjusted; the opening degree of the adjusting valve is jointly adjusted according to the vacuum degree of the steam exhaust end of the heat recovery condenser and the temperature of the outlet of the water end of the heat recovery condenser, the steam exhaust mother pipe and the steam exhaust heat recovery system are isolated through the adjusting valve, and the vacuum degree of the steam exhaust end of the heat recovery condenser is maintained within the preset range; and the dead steam flow is controlled through the regulating valve to stabilize the return water temperature of the heat recovery unit, so that the load of the heat recovery unit is adapted.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of exhaust steam heat recovery, and in particular to an exhaust steam heat recovery system, a control method thereof, an electronic device and a storage medium. BACKGROUND

[0002] In the process of power plant operation, due to the limitations of equipment and technology, the heat contained in the low-temperature and low-pressure steam, i.e. exhaust steam, discharged by the steam turbine cannot be fully recovered and utilized. This part of heat is discharged into the atmosphere, which not only causes waste but also pollutes the ecological environment. At the same time, the vacuum degree of the exhaust steam directly affects the operation of the steam turbine, which not only affects the unit efficiency but also easily increases the coal consumption of the unit. When the parameters on the side of the exhaust steam main pipe fluctuate, including the fluctuation of the exhaust steam pressure of the steam turbine, the fluctuation of the condenser vacuum degree caused by the fluctuation of the cooling water in the condenser, and the fluctuation of the exhaust steam main pipe pressure will be caused. This pressure fluctuation will cause the change of the differential pressure value of the condenser of the heat recovery system, thereby causing the fluctuation of the steam flow entering the condenser of the heat recovery system. The change of the steam pressure parameter in the exhaust steam main pipe will cause the change of the heat recovery amount of the heat recovery system, which will cause the temperature and pressure parameters of the water supply of the heat recovery system to be unable to meet the demand of the downstream users.

[0003] In the prior art, a branch pipeline of exhaust steam is connected to the exhaust steam outlet of the steam turbine to lead out part of the exhaust steam. A heat pump is driven by peak shaving surplus power or steam extraction to produce low-temperature working medium to absorb the heat of the exhaust steam, so that the low-temperature working medium condenses into condensed water and releases heat to produce residual heat water. The condensed water flows into a hot well, and the residual heat water circulates between the heat exchanger and the heat pump to heat the fluid flowing through the heat exchanger. However, this scheme can only be controlled by starting and stopping through a shut-off valve on the exhaust steam pipeline, and cannot effectively improve the system efficiency and heat exchange capacity.

[0004] In the prior art, a waste heat utilization system including a heat extraction system, a preheating system and a high-temperature heat pump is also used. The heat extraction system collects the heat of the exhaust steam and delivers it to the preheating system. The preheating system uses the heat for preheating the boiler feed water. The high-temperature heat pump is responsible for improving the heat grade output by the heat extraction system. Although this scheme can switch different heat extraction and preheating systems according to the temperature of the exhaust steam, it still cannot solve the problem of improving the heat exchange efficiency and operation stability of the unit.

[0005] In the prior art, an exhaust steam heat recovery system is composed of a steam turbine, a condenser, a waste heat recovery circuit including an expansion valve, a compressor and an evaporator, a cooling tower circulation and corresponding valves and controllers. A temperature sensor is arranged on the cooling water pipeline at the inlet of the condenser. This design mainly controls the start and stop of the cooling tower circulation by monitoring the temperature of the cooling water, which helps to reduce water consumption, but cannot enhance the heat exchange capacity of the system, and the improvement of the exhaust steam heat recovery effect is limited. SUMMARY

[0006] To solve the problems of large load fluctuation of the exhaust steam heat recovery system and large outlet water temperature fluctuation of the heat recovery condenser caused by large vacuum fluctuation of the exhaust steam end of the heat recovery condenser in the prior art, the present application provides an exhaust steam heat recovery system, a control method thereof, an electronic device and a storage medium.

[0007] The present application adopts the technical solutions as follows: The present application discloses a control method of an exhaust steam heat recovery system, comprising the following steps: obtaining the vacuum degree of the exhaust steam end of the heat recovery condenser and the temperature at the outlet of the water end of the heat recovery condenser; adjusting the opening degree of the regulating valve between the exhaust steam main pipe and the heat recovery condenser according to the vacuum degree of the exhaust steam end of the heat recovery condenser and the temperature at the outlet of the water end of the heat recovery condenser.

[0008] According to the control method, when the vacuum degree is outside the preset vacuum degree range, the opening degree of the regulating valve is adjusted according to the vacuum degree; when the vacuum degree is within the preset vacuum degree range, the opening degree of the regulating valve is adjusted according to the temperature at the outlet of the water end of the heat recovery condenser.

[0009] According to the control method, if the vacuum degree is greater than the upper limit of the preset vacuum degree range, the opening degree of the regulating valve is reduced, and after a preset time, it is determined again whether the vacuum degree is outside the preset vacuum degree range; if the vacuum degree is less than the lower limit of the preset vacuum degree range, the opening degree of the regulating valve is increased, and after a preset time, it is determined again whether the vacuum degree is outside the preset vacuum degree range.

[0010] According to the control method, if the temperature at the outlet of the water end of the heat recovery condenser is greater than a first preset temperature, the opening degree of the regulating valve is reduced; if the temperature at the outlet of the water end of the heat recovery condenser is less than a second preset temperature, the opening degree of the regulating valve is increased; wherein the first preset temperature is greater than the second preset temperature.

[0011] According to the control method, the regulating valve is provided with an initial opening degree; The method for determining the initial opening degree of the regulating valve specifically comprises: setting the exhaust steam main pipe pressure and the exhaust steam end pressure of the heat recovery condenser, and determining the first resistance of the pipeline between the exhaust steam main pipe and the exhaust steam end of the heat recovery condenser according to the difference between the set exhaust steam main pipe pressure and the exhaust steam end pressure of the heat recovery condenser; calculating the second resistance by the product of the anti-interference strength and the set exhaust steam main pipe pressure; calculating the resistance suffered by the regulating valve by the difference between the second resistance and the first resistance; According to the calculated resistance of the regulating valve and the opening and resistance characteristic curve of the regulating valve, the initial opening of the regulating valve is determined.

[0012] According to the control method, the control method further comprises: The temperature at the inlet of the water end of the heat recovery condenser is obtained, and the temperature difference is calculated by the difference between the temperature at the outlet of the water end of the heat recovery condenser and the temperature at the inlet of the water end of the heat recovery condenser, and the circulating water pump between the water end of the heat recovery condenser and the heat recovery unit is controlled according to the temperature difference.

[0013] According to the control method, the preset temperature difference is taken as a control target, the calculated temperature difference is taken as an input parameter, and the circulating water pump is controlled through a PID algorithm.

[0014] The second aspect of the present application discloses a steam exhaust heat recovery system, which runs the above-mentioned control method, comprising: a heat recovery condenser, a heat recovery unit and a controller. The water end of the heat recovery condenser is connected to the heat recovery unit in a closed loop. The inlet of the steam exhaust end of the heat recovery condenser is connected to the steam exhaust main pipe through a regulating valve. A third temperature sensor is arranged at the outlet of the water end of the heat recovery condenser, for obtaining the temperature at the outlet of the water end of the heat recovery condenser. A third pressure sensor is arranged at the steam exhaust end of the heat recovery condenser, for obtaining the vacuum degree of the steam exhaust end of the heat recovery condenser. The controller adjusts the opening of the regulating valve between the steam exhaust main pipe and the heat recovery condenser according to the vacuum degree of the steam exhaust end of the heat recovery condenser and the temperature at the outlet of the water end of the heat recovery condenser.

[0015] According to the steam exhaust heat recovery system, a second temperature sensor is arranged at the inlet of the steam exhaust end of the heat recovery condenser, and a circulating water pump is arranged between the steam exhaust end of the heat recovery condenser and the heat recovery unit. The controller controls the circulating water pump according to the temperature at the outlet of the water end of the heat recovery condenser and the temperature at the inlet of the water end of the heat recovery condenser.

[0016] The third aspect of the present application discloses an electronic device, comprising a memory, a processor and a computer program stored in the memory and capable of running on the processor, wherein the computer program is loaded into the processor to realize the above-mentioned control method.

[0017] The fourth aspect of the present application discloses a storage medium, comprising a stored program, wherein the device where the storage medium is located executes the above-mentioned control method when the program runs.

[0018] Compared with the prior art, the present application has at least the following beneficial effects: The application adjusts the opening of the regulating valve according to the vacuum degree of the exhaust steam end of the heat recovery condenser and the temperature at the outlet of the water end of the heat recovery condenser, and isolates the exhaust steam main pipe from the exhaust steam heat recovery system through the regulating valve, so as to increase the stability of the system in response to different load changes by maintaining the vacuum degree of the exhaust steam end of the heat recovery condenser within a preset range, and to stabilize the outlet water temperature of the water end of the heat recovery condenser by controlling the exhaust steam flow through the regulating valve, thereby adapting to the load of the heat recovery unit. BRIEF DESCRIPTION OF DRAWINGS

[0019] In order to more clearly illustrate the technical solutions in the embodiments of the present disclosure or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description are only some embodiments of the present disclosure, and other drawings can be obtained by those skilled in the art without creative labor.

[0020] Figure 1 The control method steps diagram of the exhaust steam heat recovery system of the present application; Figure 2 The control method flow chart of the exhaust steam heat recovery system of the present application; Figure 3 The principle diagram of the exhaust steam heat recovery system of the present application; In the figure: 1, heat recovery condenser; 2, heat recovery unit; 3, first pressure sensor; 4, regulating valve; 5, first temperature sensor; 6, second pressure sensor; 7, first flow meter; 8, second temperature sensor; 9, circulating water pump; 10, third temperature sensor; 11, second flow meter; 12, third pressure sensor; 13, exhaust steam main pipe; 14, condensate pipe; 15, vacuum extraction pipe. DETAILED DESCRIPTION

[0021] The technical solutions in the embodiments of the present disclosure will be described clearly and completely below in combination with the drawings in the embodiments of the present disclosure. Obviously, the described embodiments are only some embodiments of the present disclosure, not all the embodiments. The following description of at least one exemplary embodiment is actually only illustrative, but not as any limitation on the present disclosure and its application or use. Based on the embodiments in the present disclosure, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present disclosure.

[0022] Unless otherwise specifically stated, the relative arrangement of the components and steps, numerical expressions, and numerical values set forth in these embodiments do not limit the scope of the present disclosure.

[0023] Meanwhile, it should be understood that the sizes of the various parts shown in the drawings are not drawn in accordance with the actual proportional relationship for the convenience of description.

[0024] Techniques, methods, and devices known to those of ordinary skill in the relevant art can not be discussed in detail herein. However, where appropriate, such techniques, methods, and devices can be considered as part of the present disclosure.

[0025] In all of the compositions shown and discussed herein, any specific numerical value should be interpreted as merely an example, and not a limitation. Other examples of the exemplary embodiments can have different values.

[0026] It should be noted that like reference numerals and letters in the various figures indicate like elements, and thus, discussions of some items in one figure can also apply to like items in another figure.

[0027] To solve the problems of large fluctuation of vacuum degree at the exhaust steam end of the heat recovery condenser in the prior art, leading to large fluctuation of load of the exhaust steam heat recovery system, and large fluctuation of outlet water temperature at the water end of the heat recovery condenser, as shown in Figure 1 Embodiment 1 of the present application provides a control method of an exhaust steam heat recovery system, comprising the following steps: Step S110, obtaining the vacuum degree at the exhaust steam end of the heat recovery condenser and the temperature at the outlet of the water end of the heat recovery condenser.

[0028] Step S120, adjusting the opening degree of the regulating valve between the exhaust steam main pipe and the heat recovery condenser according to the vacuum degree at the exhaust steam end of the heat recovery condenser and the temperature at the outlet of the water end of the heat recovery condenser.

[0029] The present application adjusts the opening degree of the regulating valve according to the vacuum degree at the exhaust steam end of the heat recovery condenser and the temperature at the outlet of the water end of the heat recovery condenser, and isolates the exhaust steam main pipe and the exhaust steam heat recovery system through the regulating valve, maintains the vacuum degree at the exhaust steam end of the heat recovery condenser within a preset range, increases the stability of the system when responding to different load changes, controls the exhaust steam flow through the regulating valve, and stabilizes the outlet water temperature at the water end of the heat recovery condenser, thereby adapting to the load of the heat recovery unit.

[0030] If the vacuum degree is outside the preset vacuum degree range, then the opening degree of the regulating valve is adjusted according to the vacuum degree.

[0031] If the vacuum degree is greater than the upper limit of the preset vacuum degree range, then the opening degree of the regulating valve is reduced, and after a preset time, it is determined again whether the vacuum degree is outside the preset vacuum degree range. If the vacuum degree is less than the lower limit of the preset vacuum degree range, then the opening degree of the regulating valve is increased, and after a preset time, it is determined again whether the vacuum degree is outside the preset vacuum degree range.

[0032] The application controls the opening of the adjusting valve by comparing the measured vacuum degree with the upper limit of the preset vacuum degree range and the lower limit of the preset vacuum degree range, so that the opening of the adjusting valve is within the preset vacuum degree range.

[0033] When the vacuum degree is within the preset vacuum degree range, the opening of the adjusting valve is adjusted according to the temperature at the outlet of the water end of the heat recovery condenser.

[0034] The application preferentially adjusts the vacuum degree, and ensures the water inlet temperature of the heat recovery unit under the premise of meeting the vacuum degree.

[0035] If the temperature at the outlet of the water end of the heat recovery condenser is greater than the first preset temperature, the opening of the adjusting valve is reduced. If the temperature at the outlet of the water end of the heat recovery condenser is less than the second preset temperature, the opening of the adjusting valve is increased.

[0036] The application controls the opening of the adjusting valve by comparing the measured temperature at the outlet of the water end of the heat recovery condenser with the first preset temperature and the second preset temperature, so that the water return temperature of the heat recovery unit is stable under the premise of meeting the vacuum degree.

[0037] The first preset temperature is greater than the second preset temperature.

[0038] Preferably but not limitedly, the adjusting valve is provided with an initial opening.

[0039] In order to make the adjusting valve have the adjusting function, the adjusting valve must have an initial opening when the steam exhaust heat recovery system is normally operated. The initial opening can resist the parameter fluctuation of the other end caused by the parameter fluctuation of the steam exhaust main pipe end or the parameter fluctuation of the heat recovery condenser end. At this time, the steam flow entering the heat recovery condenser is ensured by adjusting the opening of the adjusting valve. When it is necessary to reduce the steam entering the heat recovery condenser, the opening of the adjusting valve can be reduced; when it is necessary to increase the steam entering the heat recovery condenser, the opening of the adjusting valve can be increased. When the initial opening of the adjusting valve is large, the pipe resistance is too large to affect the operation of the steam exhaust heat recovery system, causing unnecessary waste; when the initial opening of the adjusting valve is too small, it is not enough to resist the influence caused by the load output fluctuation of the steam exhaust heat recovery system.

[0040] The method for determining the initial opening of the adjusting valve specifically comprises: The steam exhaust main pipe pressure and the steam exhaust end pressure of the heat recovery condenser are set, and the first resistance of the pipeline between the steam exhaust main pipe and the steam exhaust end of the heat recovery condenser is determined according to the difference between the set steam exhaust main pipe pressure and the steam exhaust end pressure of the heat recovery condenser. The pipeline between the steam exhaust main pipe and the heat recovery condenser is arranged according to the first resistance and the resistance along the pipeline.

[0041] The second resistance is calculated by the product of the anti-interference strength and the set steam exhaust main pipe pressure.

[0042] The resistance of the adjusting valve is estimated according to the difference between the second resistance and the first resistance.

[0043] The initial opening of the adjusting valve is determined according to the estimated resistance of the adjusting valve and the opening and resistance characteristic curve of the adjusting valve.

[0044] The anti-interference strength is the maximum percentage of system allowed fluctuation, and the range is 1.1-1.3.

[0045] The present application avoids that when the initial opening of the adjusting valve is large, the pipeline resistance is too large to affect the operation of the exhaust steam heat recovery system, and causes unnecessary waste, and avoids that when the initial opening of the adjusting valve is too small, the influence caused by the load output fluctuation of the exhaust steam heat recovery system is not enough.

[0046] The control method further comprises: The temperature at the inlet of the water end of the heat recovery condenser is obtained, the temperature difference is calculated through the difference between the temperature at the outlet of the water end of the heat recovery condenser and the temperature at the inlet of the water end of the heat recovery condenser, and the circulating water pump between the water end of the heat recovery condenser and the heat recovery unit is controlled according to the temperature difference.

[0047] The circulating water pump between the water end of the heat recovery condenser and the heat recovery unit is controlled through the difference between the temperature at the outlet of the water end of the heat recovery condenser and the temperature at the inlet of the water end of the heat recovery condenser, so that the return water temperature of the heat recovery unit is further stabilized.

[0048] Specifically, the preset temperature difference is taken as a control target, the calculated temperature difference is taken as an input parameter, and the circulating water pump is controlled through a PID algorithm.

[0049] The circulating water pump is controlled through the PID algorithm, so that the response speed and stability are improved.

[0050] As shown in Figure 2 Fig. 2, the embodiment 2 of the present application provides a preferred embodiment of a control method of an exhaust steam heat recovery system, which comprises the following steps: In step S210, the vacuum degree PT3 of the exhaust steam end of the heat recovery condenser and the temperature TT3 at the outlet of the water end of the heat recovery condenser are obtained.

[0051] In step S220, the opening of the adjusting valve between the exhaust steam main pipe and the heat recovery condenser is adjusted according to the vacuum degree PT3 of the exhaust steam end of the heat recovery condenser, the temperature TT3 at the outlet of the water end of the heat recovery condenser, a preset vacuum degree range, a first preset temperature and a second preset temperature.

[0052] When the vacuum degree is outside the preset vacuum degree range, the opening of the adjusting valve is adjusted according to the vacuum degree.

[0053] If the vacuum degree PT3 is greater than the upper limit of the preset vacuum degree range, the opening of the adjusting valve is reduced, and after a preset time, it is judged again whether the vacuum degree PT3 is outside the preset vacuum degree range; If the vacuum degree PT3 is less than the lower limit of the preset vacuum degree range, the opening of the adjusting valve is increased, and after a preset time, it is judged again whether the vacuum degree PT3 is outside the preset vacuum degree range.

[0054] The upper limit of the preset vacuum degree range is the preset vacuum degree PT31 plus a preset vacuum degree deviation value ΔPT; and the lower limit of the preset vacuum degree range is the preset vacuum degree PT31 minus the preset vacuum degree deviation value ΔPT.

[0055] When the vacuum degree is within the preset vacuum degree range, the opening of the adjusting valve is adjusted according to the temperature at the outlet of the water end of the heat recovery condenser.

[0056] If the temperature TT3 at the outlet of the water end of the heat recovery condenser is greater than the preset temperature TT31 plus a preset temperature deviation value ΔTT, the opening of the adjusting valve is reduced; If the temperature TT3 at the outlet of the water end of the heat recovery condenser is less than the preset temperature TT31 minus the preset temperature deviation value ΔTT, the opening of the adjusting valve is increased.

[0057] Preferably but not limitedly, the adjusting valve is provided with an initial opening.

[0058] The method for determining the initial opening of the adjusting valve specifically comprises: Setting the exhaust steam main pressure and the exhaust steam end pressure of the heat recovery condenser, determining the first resistance H1 of the pipeline between the exhaust steam main and the exhaust steam end of the heat recovery condenser according to the difference between the set exhaust steam main pressure and the set exhaust steam end pressure of the heat recovery condenser, and arranging the pipeline between the exhaust steam main and the exhaust steam end of the heat recovery condenser according to the first resistance H1 and the formula of the resistance along the pipeline.

[0059] That is, the first resistance H1 = the set exhaust steam main pressure - the set exhaust steam end pressure of the heat recovery condenser; The second resistance H2 is calculated by the product of the anti-interference strength A and the set exhaust steam main pressure.

[0060] That is, the second resistance H2 = the anti-interference strength A * the set exhaust steam main pressure; The resistance borne by the adjusting valve is estimated according to the difference between the second resistance H2 and the first resistance H1.

[0061] That is, the resistance borne by the adjusting valve = the second resistance H2 - the first resistance H1.

[0062] According to the estimated resistance of the regulating valve and the opening and resistance characteristic curve of the regulating valve, the initial opening of the regulating valve is determined.

[0063] The anti-interference strength A is the upper limit percentage of the fluctuation allowed by the system, that is, the maximum percentage, and the value range is 1.1-1.3.

[0064] The control method further comprises: The temperature at the inlet of the water end of the heat recovery condenser is obtained, and the temperature difference is calculated by the difference between the temperature at the outlet of the water end of the heat recovery condenser and the temperature at the inlet of the water end of the heat recovery condenser, and the circulating water pump between the water end of the heat recovery condenser and the heat recovery unit is controlled according to the temperature difference.

[0065] Specifically, the preset temperature difference is taken as a control target, the calculated temperature difference is taken as an input parameter, and the circulating water pump is controlled through a PID algorithm.

[0066] As shown in Figure 3 Embodiment 3 of the present application provides a steam exhaust heat recovery system, comprising: a heat recovery condenser 1, a heat recovery unit 2 and a controller.

[0067] The water end of the heat recovery condenser 1 is connected in a closed loop with the heat recovery unit 2.

[0068] The inlet of the steam exhaust end of the heat recovery condenser 1 is connected with the steam exhaust main pipe 13 through a regulating valve 4.

[0069] The outlet of the water end of the heat recovery condenser 1 is provided with a third temperature sensor 10 for obtaining the temperature TT3 at the outlet of the water end of the heat recovery condenser 1.

[0070] The steam exhaust end of the heat recovery condenser 1 is provided with a third pressure sensor 12 for obtaining the vacuum degree PT3 of the steam exhaust end of the heat recovery condenser 1.

[0071] The controller adjusts the opening of the regulating valve between the steam exhaust main pipe 13 and the heat recovery condenser according to the vacuum degree of the steam exhaust end of the heat recovery condenser 1 and the temperature at the outlet of the water end of the heat recovery condenser 1.

[0072] Preferably but not limitedly, the inlet of the steam exhaust end of the heat recovery condenser 1 is provided with a second temperature sensor 8, and a circulating water pump 9 is arranged between the steam exhaust end of the heat recovery condenser 1 and the heat recovery unit 2.

[0073] The controller controls the circulating water pump 9 according to the temperature at the outlet of the water end of the heat recovery condenser and the temperature at the inlet of the water end of the heat recovery condenser.

[0074] Preferably but not limitedly, a second flow meter 11 is further arranged between the water end of the heat recovery condenser 1 and the heat recovery unit 2.

[0075] The controller can also calculate the condensing recovery amount according to the data of the second temperature sensor 8, the third temperature sensor 10 and the second flow meter 11, so as to evaluate the condensing effect of the heat recovery condenser.

[0076] Further preferably but not limitedly, the condensing recovery amount is equal to the product of the temperature difference between the inlet and outlet and the flow, and the product of the difference between the data of the third temperature sensor 10 and the second temperature sensor 8 and the data of the second flow meter 11.

[0077] The first pressure sensor 3 is arranged between the steam exhaust main pipe 13 and the regulating valve 4, and the first temperature sensor 5, the second pressure sensor 6 and the first flow meter 7 are arranged between the regulating valve 4 and the steam exhaust end of the heat recovery condenser 1.

[0078] The first pressure sensor 3 is arranged between the steam exhaust main pipe 13 and the regulating valve 4, and the first temperature sensor 5, the second pressure sensor 6 and the first flow meter 7 are arranged between the regulating valve 4 and the steam exhaust end of the heat recovery condenser 1.

[0079] The second pressure sensor 6 is arranged between the regulating valve 4 and the steam exhaust end of the heat recovery condenser 1.

[0080] The steam exhaust end of the heat recovery condenser 1 is connected with the condensate pipe 14, and is also connected with a vacuum extraction device through the vacuum extraction pipe 15, so as to remove the non-condensable gas in the steam exhaust end of the heat recovery condenser 1.

[0081] Preferably but not limitedly, the vacuum extraction device can be the vacuum extraction system of the power plant, or can be a separate vacuum pump.

[0082] The steam exhaust main pipe 13 is the main pipe for discharging the low-pressure exhaust steam of the steam turbine to the condenser.

[0083] The heat recovered by the heat recovery unit 2 is supplied to other devices or places in the form of high-grade hot water or steam.

[0084] Embodiment 4 of the present application provides an electronic device, which comprises a memory, a processor and a computer program stored in the memory and capable of running on the processor, and the computer program realizes the above-mentioned control method when loaded into the processor.

[0085] Embodiment 5 of the present application provides a storage medium, which comprises a stored program, and when the program runs, the storage medium controls the device where the storage medium is located to execute the above-mentioned control method.

[0086] The storage media can be a tangible device that can retain and store instructions for use by an instruction execution device. The storage media can be, for example, but is not limited to, an electronic storage device, a magnetic storage device, an optical storage device, an electromagnetic storage device, a semiconductor storage device, or any suitable combination of the foregoing. More specific examples (a non-exhaustive list) of the storage media include the following: a portable computer diskette, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or Flash memory), a static random access memory (SRAM), a portable compact disc read-only memory (CD-ROM), a digital versatile disk (DVD), a memory stick, a floppy disk, a mechanically encoded device such as punch-cards or raised structures in a groove having instructions recorded thereon, and any suitable combination of the foregoing. A storage media reader, which can be located in or peripheral to a computing device, is used to read the instructions stored in the storage media for execution by the instruction execution device.

[0087] Computer readable program instructions described herein can be downloaded to respective computing / processing devices from a storage media or to an external computer or external storage device via a network, for example, the Internet, a local area network, a wide area network and / or a wireless network. The network can comprise copper transmission cables, optical transmission fibers, wireless transmission, routers, firewalls, switches, gateway computers and / or edge servers. A network adapter card or network interface in each computing / processing device receives computer readable program instructions from the network and forwards the computer readable program instructions for storage in a storage medium within the respective computing / processing device.

[0088] Computer readable program instructions for carrying out operations of the present disclosure can be assembly instructions, instruction set architecture (ISA) instructions, machine instructions, machine dependent instructions, microcode, firmware instructions, state-setting data, or either source code or object code written in any combination of one or more programming languages, including an object oriented programming language such as Smalltalk, C++ or the like, and conventional procedural programming languages such as the "C" programming language or similar programming languages. The computer readable program instructions can execute entirely on the user's computer, partly on the user's computer, as a stand-alone software package, partly on the user's computer and partly on a remote computer or entirely on the remote computer or server. In the latter scenario, the remote computer can be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or the connection can be made to an external computer (for example, through the Internet using an Internet Service Provider). In some embodiments, electronic circuitry including, for example, programmable logic circuitry, field-programmable gate array (FPGA), or programmable logic array (PLA) can execute the computer readable program instructions by utilizing state information of the computer readable program instructions to personalize the electronic circuitry, in order to perform aspects of the present disclosure.

[0089] Finally, it should be noted that the above-mentioned embodiments are merely used to illustrate the technical solutions of the present application, rather than limiting the present application, and although the present application has been described in detail with reference to the above-mentioned embodiments, those skilled in the art should understand that the specific embodiments of the present application can be modified or replaced equivalently without departing from the spirit and scope of the present application, and any modification or equivalent replacement without departing from the spirit and scope of the present application should be covered in the protection scope of the claims of the present application.

Claims

1. A control method for a waste steam heat recovery system, characterized in that, Includes the following steps: Obtain the vacuum level at the exhaust steam end of the heat recovery condenser and the temperature at the water outlet of the heat recovery condenser; Adjust the opening of the regulating valve between the exhaust steam header and the heat recovery condenser based on the vacuum level at the exhaust steam end of the heat recovery condenser and the temperature at the water outlet of the heat recovery condenser.

2. The control method according to claim 1, characterized in that: When the vacuum level is outside the preset vacuum level range, the opening of the regulating valve is adjusted according to the vacuum level. When the vacuum level is within the preset vacuum level range, the opening of the regulating valve is adjusted according to the temperature at the water outlet of the heat recovery condenser.

3. The control method according to claim 2, characterized in that: If the vacuum level is greater than the upper limit of the preset vacuum level range, the opening of the regulating valve is reduced, and after a preset time, it is determined again whether the vacuum level is outside the preset vacuum level range. If the vacuum level is less than the lower limit of the preset vacuum level range, the opening of the regulating valve is increased, and after a preset time, it is determined again whether the vacuum level is outside the preset vacuum level range.

4. The control method according to claim 2, characterized in that: If the temperature at the water outlet of the heat recovery condenser is greater than the first preset temperature, then reduce the opening of the regulating valve; If the temperature at the water outlet of the heat recovery condenser is lower than the second preset temperature, the opening of the regulating valve is increased. The first preset temperature is greater than the second preset temperature.

5. The control method according to claim 1, characterized in that: The regulating valve is provided with an initial opening degree; The method for determining the initial opening degree of the regulating valve specifically includes: Set the pressure of the exhaust steam header and the pressure of the exhaust steam end of the heat recovery condenser. Based on the difference between the set pressure of the exhaust steam header and the pressure of the exhaust steam end of the heat recovery condenser, determine the first resistance of the pipeline between the exhaust steam header and the exhaust steam end of the heat recovery condenser. The second resistance is calculated by multiplying the anti-interference strength by the set exhaust steam header pressure; The resistance experienced by the regulating valve is calculated by the difference between the second resistance and the first resistance. The initial opening of the control valve is determined based on the calculated resistance of the control valve and the valve's opening and resistance characteristic curve.

6. The control method according to claim 1, characterized in that, The control method further includes: The temperature at the inlet of the water end of the heat recovery condenser is obtained, and the temperature difference is calculated by the difference between the temperature at the outlet of the water end of the heat recovery condenser and the temperature at the inlet of the water end of the heat recovery condenser. The circulating water pump between the water end of the heat recovery condenser and the heat recovery unit is controlled according to the temperature difference.

7. The control method according to claim 6, characterized in that: The circulating water pump is controlled by a PID algorithm with a preset temperature difference as the control target and the calculated temperature difference as the input parameter.

8. A waste steam heat recovery system, implementing the control method according to any one of claims 1-7, characterized in that, include: Heat recovery condenser (1), heat recovery unit (2) and controller; The water end of the heat recovery condenser (1) is connected in a closed loop to the heat recovery unit (2); The exhaust steam inlet of the heat recovery condenser (1) is connected to the exhaust steam header (13) via a regulating valve (4); A third temperature sensor (10) is provided at the water outlet of the heat recovery condenser (1) to obtain the temperature at the water outlet of the heat recovery condenser (1); The heat recovery condenser (1) is equipped with a third pressure sensor (12) at the exhaust steam end, which is used to obtain the vacuum degree at the exhaust steam end of the heat recovery condenser (1). The controller adjusts the opening of the regulating valve (4) between the exhaust steam header and the heat recovery condenser (1) based on the vacuum degree at the exhaust steam end of the heat recovery condenser (1) and the temperature at the water outlet of the heat recovery condenser (1).

9. The waste steam heat recovery system according to claim 8, characterized in that: The heat recovery condenser (1) is equipped with a second temperature sensor (8) at the exhaust steam inlet, and a circulating water pump (9) is provided between the exhaust steam end of the heat recovery condenser (1) and the heat recovery unit (2). The controller controls the circulating water pump (9) based on the temperature at the water outlet of the heat recovery condenser (1) and the temperature at the water inlet of the heat recovery condenser (1).

10. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the computer program is loaded into the processor, it implements the control method according to any one of claims 1-7.

11. A storage medium, characterized in that: The storage medium includes a stored program, wherein, when the program is executed, it controls the device containing the storage medium to perform the control method according to any one of claims 1-7.

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