Steam condensing equipment

Abstract

The utility model provides steam condensing equipment which is used for treating dead steam exhausted from a steam turbine. In the steam condensing equipment, a switching assembly is arranged to enable the steam condensing equipment to be switched between a first state and a second state. The pipeline system is arranged in the mode that in the first state, dead steam enters the first condenser of the two condensers to be condensed and then is sent to the downstream, and the dead steam is prevented from entering the second condenser of the two condensers. The pipeline system is arranged in the mode that in the second state, dead steam is divided into two paths, the two paths of dead steam enter the two condensers respectively, and condensed water formed through condensation in the two condensers is fed to the downstream after being converged. The steam condensing equipment can meet the requirements of different steam amounts.

Description

Technical Field

[0001] The utility model belongs to the field of steam turbine exhaust steam condensation, and relates to a steam condensation device. Background Art

[0002] As a main auxiliary machine of a steam turbine, a direct air cooling system is the main steam condensation device of steam turbines in many regions, such as power generation steam turbines and industrial steam turbines. The direct air cooling system has been recognized by society for its advantages of no pollution, theoretically no water consumption, and no restriction by water sources, and is even compulsorily adopted in some regions.

[0003] However, sometimes, the amount of steam to be processed by the same set of steam condensation devices varies greatly at different times. For example, in some regions, due to climate problems, the amount of steam to be processed changes particularly greatly throughout the year. Therefore, the economy of the air-cooled unit is sometimes acceptable and sometimes particularly poor.

[0004] Therefore, it is desirable to provide a steam condensation device with greater versatility and stronger adaptability. Summary of the Utility Model

[0005] The purpose of the utility model is to provide a steam condensation device that can adapt to different steam volume requirements.

[0006] The utility model provides a steam condensation device for processing the exhaust steam discharged from a steam turbine. The steam condensation device includes a pipeline system, two condensers, and a switching component. The switching component is configured to enable the steam condensation device to switch between a first state and a second state. The pipeline system is configured such that in the first state, the exhaust steam enters the first condenser of the two condensers for condensation and then is sent downstream, and the exhaust steam is prevented from entering the second condenser of the two condensers. The pipeline system is configured such that in the second state, the exhaust steam is divided into two paths and enters the two condensers respectively, and after the condensed water formed in the two condensers converges, it is sent downstream.

[0007] In one embodiment, the steam condensation device further includes a water collection tank, and the pipeline system is configured such that the exhaust steam enters the condenser after passing through the water collection tank.

[0008] In one embodiment, the pipeline system is further configured such that the condensed water formed in the condenser is sent to the water collection tank, and the cold water collected in the water collection tank is discharged outward.

[0009] In one embodiment, at least one of the two condensers is a condenser that requires cooling water. The pipeline system is configured such that the cold water is pumped outward by a discharge pump, and the pipeline system is further configured such that at least a part of the cold water pumped by the discharge pump is sent to at least one condenser as cooling water.

[0010] In one embodiment, the two condensers are of different types.

[0011] In one embodiment, the second condenser has a higher condensation efficiency than the first condenser.

[0012] In one embodiment, the first condenser and the second condenser are an air-cooled condenser and an evaporative condenser respectively.

[0013] In one embodiment, the pipeline system is arranged such that the suction pipelines respectively sucked from the air-cooled condenser and the evaporative condenser converge and then are connected to the same suction device.

[0014] In one embodiment, the pipeline system includes a first pipeline and a second pipeline that respectively convey condensate downstream from the first condenser and the second condenser. The switching assembly includes a switching valve provided in the second pipeline, and the steam condensation device realizes state switching by opening and closing the switching valve.

[0015] In one embodiment, the steam condensation device further includes a controller and a detector. The detector is used to detect the flow rate of the exhaust steam discharged from the steam turbine and send a detection signal to the controller, and the controller sends an opening and closing signal to the switching valve according to the detection signal.

[0016] In the above steam condensation device, the steam condensation device can, for example, default to the first state and only use the first condenser, but switch to the second state when the amount of steam to be processed is relatively high, and enable the second condenser as a peak cooling device. In this way, the above steam condensation device can adapt to the demands of different steam amounts throughout the life cycle while optimizing economy, and process or consume different amounts of steam exhaust. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The advantages and spirit of the present utility model can be further understood through the following detailed description and the drawings.

[0018] Figure 1 is a schematic diagram of an exemplary steam condensation device provided by the present utility model. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0019] The specific embodiments of the present utility model will be described in detail below with reference to the drawings. However, it should be understood that the present utility model is not limited to the embodiments described below, and the technical concept of the present utility model can be implemented in combination with other known technologies or functions, or with other technologies that are the same as those known technologies.

[0020] For example, the first feature described subsequently in the specification may be formed above or on the second feature, which may include embodiments in which the first feature and the second feature are formed by direct connection, and may also include embodiments in which additional features are formed between the first feature and the second feature, so that the first feature and the second feature may not be directly connected. Further, when the first element is described as being connected or combined with the second element, this description includes embodiments in which the first element and the second element are directly connected or combined with each other, and also includes embodiments in which one or more other intervening elements are added to indirectly connect or combine the first element and the second element with each other.

[0021] Taking the northwest inland area of China as an example, most of this area belongs to the mid-temperate arid zone, with typical continental climate characteristics. It is cold in winter, dry in spring, hot in summer, with a large temperature difference between day and night, and there are more sandstorm days in winter and spring. Due to the above objective external factors such as temperature, strong wind, and dust, combined with the decrease in the system vacuum tightness and the increase in the fouling thermal resistance with the increase in the service life of the equipment, the heat transfer performance of the direct air-cooled condenser deteriorates, resulting in the following problems faced by the unit during operation. First, when the ambient temperature is relatively high in summer, the steam consumption increases and the economy of the unit decreases. Second, affected by the strong wind in the environment, the back pressure of the unit rises suddenly and the safety of the unit decreases. Third, the power consumption of the air-cooled condenser fan is large and the production plant power consumption rate is high.

[0022] The inventor analyzed and believed that for an air-cooled unit, increasing the heat dissipation capacity of the cold end of the air-cooled unit to reduce the exhaust steam pressure of the steam turbine is an effective method to significantly improve the thermal economy of the unit and can also ensure its safe operation. Therefore, the present utility model adds an evaporative condenser as the second condenser as a peak cooling device to increase the heat dissipation capacity of the cold end of the air-cooled unit.

[0023] As Figure 1 shown, the steam condensation device 10 is used to process the exhaust steam G1 discharged from the steam turbine 20. The steam condensation device 10 includes a pipeline system 1, two condensers 2, and a switching component 3. It can be understood that the drawings in this text are only examples and are not necessarily drawn according to the condition of equal proportion, and should not be regarded as constituting a limitation to the actual protection scope required by the present utility model.

[0024] The pipeline system is also a pipe network including multiple pipelines. The condenser is also a heat exchanger that directly condenses a gas into a liquid by exchanging heat with a cooling medium.

[0025] The switching component 3 is arranged such that the steam condensation device 10 switches between a first state T1 and a second state T2.

[0026] The pipeline system 1 is arranged such that in the first state T1, the exhaust steam G1 enters the first condenser 21 among the two condensers 2 to be condensed and then sent downstream, and prevents the exhaust steam G1 from entering the second condenser 22 among the two condensers 2.

[0027] The pipeline system 1 is configured such that in the second state T2, the exhaust steam G1 is divided into two paths ( Figure 1 in the figure, paths 11 and 12), and respectively enter two condensers 21 and 22. After the condensed water Y1 formed by condensation in the two condensers 21 and 22 converges, it is sent downstream.

[0028] In the above steam condensation device 10, the second condenser 22, such as the evaporative condenser described later, can be used as the peak cooling device of the entire system, for example, it can be used only in high-temperature and strong-wind weather in summer. When the ambient temperature decreases and the unit load and back pressure both meet the normal operation requirements, the second condenser 22 can be taken out of service, and only the first condenser 21, such as the air-cooled condenser, is used.

[0029] Therefore, the above steam condensation device 10 can adapt to different requirements throughout the year, and costs, energy consumption, etc. can all be optimized.

[0030] It can be understood that the terms "first" and "second" are only used for descriptive purposes, and do not refer to limitations on time sequence, quantity, or importance. It cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features, but only for distinguishing one technical feature in the present technical solution from another technical feature. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present utility model, the meaning of "a plurality" is two or more than two (that is, more than two), unless otherwise clearly and specifically defined. Similarly, the limiting terms similar to "a" appearing in the text do not refer to limitations on quantity, but describe technical features that have not appeared before. Similarly, unless it is a noun modified by a specific quantitative word, the text should be regarded as including both the singular form and the plural form, and in this technical solution, it can include a single one of such technical features or a plural number of such technical features.

[0031] As Figure 1 shown, the steam condensation device 10 further includes a water collection tank 4. The pipeline system 1 is configured such that the exhaust steam G1 enters the condensers 21 and 22 after passing through the water collection tank 4. Before entering the condenser 2, the exhaust steam G1 is pre-dewatered or water-collected by the water collection tank 4, which can save the energy consumption of the condenser 2.

[0032] It can be understood that when it is described in the text that a certain fluid stream enters the first component and then the second component in sequence or similar descriptions are used, it only indicates the order in which the fluid stream enters the first component and the second component, and does not exclude the situation that the fluid stream also passes through a third component between the first component and the second component, nor does it exclude the situation that the fluid stream also passes through a third component before the first component or after the second component. For example, when it is previously described that the exhaust steam G1 enters the condenser 2, it does not exclude the situation that the exhaust steam G1 is drained or collected by the water collecting tank 4 before entering the condenser 2.

[0033] It can also be understood that the term "and / or" used in the text includes any and all combinations of one or more of the related listed items. Unless otherwise specified, the meanings of all terms (including technical and scientific terms) used in the text are the same as those commonly understood by those of ordinary skill in the field to which this utility model belongs. It should also be understood that terms, such as those defined in common dictionaries, should be understood to have meanings consistent with their meanings in the context of this specification and the relevant field, and should not be understood in an idealized or overly formal sense unless explicitly specified in the text. For the sake of brevity and / or clarity, well-known functions or structures may not be described in detail.

[0034] As Figure 1 As shown, the pipeline system 1 is also arranged such that the condensate water Y1 formed by condensation in the condensers 21 and 22 is sent to the water collecting tank 4, and the cold water Y2 collected in the water collecting tank 4 is discharged outwards. For example, the cold water Y2 is discharged outwards through the discharge pump 6. In this way, the water condensed by the condensers 21 and 22 and the water obtained by being processed by the water collecting tank 4 before entering the condenser 2 are gathered together, which is convenient for further delivery to the downstream.

[0035] As Figure 1 As shown, at least one of the two condensers 2, such as the condenser 22, is a condenser that requires cooling water Y3. The pipeline system 1 is arranged such that the cold water Y2 is pumped outwards through the discharge pump 6. The pipeline system 1 is also arranged such that at least a part of the cold water Y2 pumped by the discharge pump 6 is sent to the aforementioned at least one condenser 22 as the cooling water Y3. Figure 1 Among the two condensers 2 shown, only the second condenser 22 requires the cooling water Y3. Figure 1 In the [description], a branch is separated from the downstream of the discharge pump 6 and leads to the second condenser 22, and a control valve 33 is also provided on this branch. Through this branch, the cooling water Y3 (also called spray water in an evaporative condenser) is first cooled by heat exchange through the heat exchanger 82 and then sent into the second condenser 22. Here, a recycling is formed, which can save energy and increase efficiency.

[0036] As Figure 1As shown, the two condensers 21 and 22 are of different types. The second condenser 22 can have a higher condensation efficiency than the first condenser 21, particularly, slightly higher. The condensation efficiency can be defined, for example, by the ratio of the condensed liquid to the non-condensable gas per unit time. Figure 1 In the illustrated embodiment, the first condenser 21 and the second condenser 22 are an air-cooled condenser and an evaporative condenser, respectively.

[0037] An air-cooled condenser is a surface heat exchanger that uses air as the cooling medium to directly cool into condensed water. An evaporative condenser is a heat exchange device that uses cooling water as the cooling medium. Generally, in an evaporative condenser, the spray cooling water is sent to the upper part of the heat exchange module by a small circulating water pump ( Figure 1 in, 81), and is evenly sprayed on the outer surface of the heat exchange tubes through a nozzle to form a uniform water film. The exhaust steam processed by the water collecting tank enters the heat exchange module from the steam inlet and is evenly distributed to each heat exchange tube. Phase changes occur simultaneously inside and outside the heat exchange tubes. The heat released by the condensation of the steam inside the tubes and the heat absorbed by the evaporation of the spray water outside the tubes, and the simultaneous occurrence of phase changes inside and outside are the most efficient heat transfer processes. After the steam inside the heat exchange tubes condenses, it is collected in the condensate tank through the condensate pipeline, and the non-condensable gas generated by the system is discharged by the vacuum pumping system. After the water film outside the heat exchange tubes evaporates into water vapor, under the forced action of the fan, the heat is finally transferred to the air in a saturated state.

[0038] In this way, during the flat peak period, only the air-cooled condenser is used for condensation, which can save energy consumption and resources. During the peak period, an evaporative condenser with higher efficiency is added to meet the peak cooling demand.

[0039] As Figure 1 shown, the pipeline system 1 is arranged such that the suction pipelines 17 and 18 respectively sucked from the air-cooled condenser (as an example of the first condenser 21) and the evaporative condenser (as an example of the second condenser 22) converge and then are connected to the same suction device 7. The suction device 7 can be, for example, a vacuum pumping device. Setting the suction device can increase the condensation efficiency. Sharing the same suction device for both can save costs while meeting the usage requirements.

[0040] As Figure 1 shown, the pipeline system 1 includes a first pipeline 15 and a second pipeline 16 that respectively convey the condensate Y1 from the first condenser 21 and the second condenser 22 downstream. The switching assembly 3 includes a switching valve 31 provided in the second pipeline 16. The steam condensation device 10 realizes the state switching by opening and closing the switching valve 31. This enables convenient switching.

[0041] As Figure 1As shown, the steam condensing device 10 further includes a controller 51 and a detector 52. The detector 52 is used to detect the flow rate of the exhaust steam G1 discharged from the steam turbine 20 and send a detection signal to the controller 51. For example, the detector 52 can detect the flow rate of the exhaust steam G1 (also often referred to as exhaust steam in this case) after being drained by the water collecting tank 4. The controller 51 sends an opening and closing signal to the switching valve 31 according to the detection signal. In this way, automatic switching can be achieved.

[0042] The detector may be, for example, various sensors, such as a pressure sensor, an optical sensor, an ultrasonic sensor, etc. The controller may be one or more application specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DAPDs), programmable logic devices (PLDs), field programmable gate arrays (FPGAs), processors, controllers, microcontrollers, microprocessors, or combinations thereof. The figure only shows the connection between the controller 51 and the detector 52 and the switching valve 31 by way of example with dotted lines, but in fact, the controller 51 and the like may also be connected to other elements such as control valves 32 and 33. These connections may be wired connections or wireless connections. The control valves 32 and 33 may also be part of the switching assembly 3. When it is necessary to switch to the first state T1, the control valves 32 and 33 may be closed while the switching valve 31 is closed, and when it is necessary to switch to the second state T2, the control valves 32 and 33 may be opened while the switching valve 31 is opened.

[0043] like Figure 1 As shown, the steam condensing device 10 can process the exhaust steam G1 discharged from the steam turbine 20 of the air separation system 100. In the air separation system 100, the steam turbine 20 can be used as a power device of the compressor unit. The steam turbine 20 can also be used for other purposes, such as power generation.

[0044] Unless clearly indicated to the contrary, each aspect or embodiment defined herein may be combined with any other aspect or embodiments. In particular, any feature indicated as preferred or advantageous may be combined with any other feature indicated as preferred or advantageous.

[0045] The present specification only describes the preferred specific embodiments of the present invention. The above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the present invention. Any technical solutions that can be obtained by a person skilled in the art through logical analysis, reasoning or limited experiments based on the concept of the present invention should be within the scope of the present invention.

Claims

1. A steam condensing device for treating exhaust steam discharged from a steam turbine, characterized in that: The invention comprises a pipeline system, two condensers and a switching assembly, wherein the switching assembly is configured to switch the steam condensing device between a first state and a second state. The pipeline system is configured such that, in the first state, the exhaust steam enters the first condenser of the two condensers and is sent downstream after being condensed, and the exhaust steam is prevented from entering the second condenser of the two condensers; The pipeline system is configured such that, in the second state, the exhaust steam is divided into two paths and enters the two condensers respectively, and the condensed water formed by condensation in the two condensers is combined and sent to the downstream.

2. The steam condensing device according to claim 1, characterized in that: It also includes a water collecting tank, and the pipeline system is configured so that the exhaust steam enters the condenser after passing through the water collecting tank.

3. The steam condensing device according to claim 2, characterized in that: The pipeline system is also configured to allow condensed water formed by condensation in the condenser to be sent to the water collecting tank, and to allow cold water collected in the water collecting tank to be discharged externally.

4. The steam condensing device according to claim 3, characterized in that: At least one of the two condensers is a condenser requiring cooling water; The pipeline system is configured such that the cold water is pumped outward via a discharge pump, and the pipeline system is further configured such that at least a portion of the cold water pumped via the discharge pump is fed into the at least one condenser as the cooling water.

5. The steam condensing device according to claim 1, characterized in that: The two condensers are of different types.

6. The steam condensing device according to claim 5, characterized in that: The second condenser is higher in condensation efficiency than the first condenser.

7. The steam condensing device according to claim 5, characterized in that: The first condenser and the second condenser are an air-cooled condenser and an evaporative condenser, respectively.

8. The steam condensing device according to claim 7, characterized in that: The pipeline system is configured so that the suction pipelines respectively drawn from the air-to-air condenser and the evaporative condenser are connected to the same suction device after merging.

9. The steam condensing device according to claim 1, characterized in that: The pipeline system includes a first delivery pipeline and a second delivery pipeline for respectively delivering condensate from the first condenser and the second condenser to downstream; The switching component includes a switching valve arranged on the second delivery pipeline, and the steam condensing device realizes state switching by opening and closing the switching valve.

10. The steam condensing device according to claim 9, characterized in that It also includes a controller and a detector, wherein the detector is used to detect the flow rate of exhaust steam discharged from the steam turbine and send a detection signal to the controller, and the controller sends an opening and closing signal to the switching valve according to the detection signal.

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