Self-circulation flash heat pump steam supply system

Abstract

The utility model relates to the field of heat pump steam supply, in particular to a self-circulation flash evaporation heat pump steam supply system. The system comprises a flash evaporation device, a cascade heat pump heating device, a water supplementing pipeline and a steam supply pipeline, the cascade heat pump heating device comprises a first condenser and a second condenser, the second condenser is arranged in a flash evaporation tank, water working media in the flash evaporation tank are heated through the second condenser, heat of the cascade heat pump heating device is fully utilized, and the heat utilization rate of the water working media is improved. The heat loss is reduced, the temperature of the water working medium subjected to flash evaporation can be effectively increased, and the flash evaporation amount is increased; the water replenishing pipeline replenishes water into the flash tank after being heated by the first condenser of the cascade heat pump heating device, so that the temperature of the replenished water is increased, the influence of too low temperature of the replenished water on the operation of the system is reduced, and the operation energy consumption of the system is also reduced.

Description

Technical Field

[0001] The present application relates to the field of heat pump steam supply, and more particularly to a heat pump steam supply system with self-circulating flash evaporation. Background Art

[0002] In the current situation of tightening energy supply and increasing environmental protection requirements, people are constantly looking for new energy sources that are both energy-saving and environmentally friendly. Heat pumps are one of these new energy sources. Since heat pumps can transfer low-temperature heat energy to high-temperature heat energy, they can make full use of the heat in natural resources and waste heat resources, effectively saving the primary energy required for civil and industrial use. As a new heating technology, heat pumps have not only received widespread attention, but have also been rapidly applied to practical projects and have achieved good results.

[0003] At present, there are some technical means for supplying high-temperature and high-pressure steam through heat pump technology, especially the coupling of heat pump technology and water vapor compression technology is used to further increase the temperature and pressure of the supplied steam. However, when these technologies are used for heating, on the one hand, the preheating problem of make-up water is rarely considered, and the make-up water is directly introduced into the system, which not only reduces the heating temperature in the system and affects the safe and stable operation of the system, but also affects the amount of steam generated to a certain extent, which is not conducive to the generation of steam. On the other hand, an external circulation method is adopted to pump out the water in the flash tank, and then flow through the heat exchanger to heat the hot water to achieve flash evaporation. The water flow rate of this method will be limited by the heat exchanger, and it is difficult to adjust the circulation flow rate. At the same time, the heat exchange temperature difference is large, and there is a disadvantage of large heat loss. Utility Model Content

[0004] In order to solve or at least partially solve the above technical problems, the present application provides a heat pump steam supply system for self-circulating flash evaporation, comprising:

[0005] A flash evaporation device, comprising a flash evaporation tank and a flash evaporation circulation pipeline connected to the flash evaporation tank;

[0006] A cascade heat pump heating device, comprising a first heat pump circulation pipeline and a second heat pump circulation pipeline, wherein a heat exchange side of a first condenser of the first heat pump circulation pipeline is connected to the second heat pump circulation pipeline, and a second condenser of the second heat pump circulation pipeline is disposed in the flash tank and at least partially contacts with liquid water in the flash tank;

[0007] a water supply pipeline connected to the flash tank through the heat exchange side of the first condenser;

[0008] The steam supply pipeline is connected to the output end of the flash tank and is used to process the steam generated by the flash tank.

[0009] Optionally, the second condenser comprises a spiral condensation coil, and the spiral condensation coil is spirally arranged upward from the bottom of the flash tank.

[0010] Optionally, the radial dimension of the spiral circumference formed by the spiral condensing coil gradually decreases from the bottom of the flash tank upward.

[0011] Optionally, all of the spiral condensation coils are disposed in liquid water in the flash tank.

[0012] Optionally, the steam supply pipeline further includes a first steam compressor and a second steam compressor, wherein the first steam compressor is connected to the output end of the flash tank through a pipeline, and the second steam compressor is connected to a downstream pipeline of the first steam compressor.

[0013] Optionally, the steam supply pipeline further includes a steam cooler, one heat exchange side of the steam cooler is connected to the flash circulation pipeline, and the other heat exchange side of the steam cooler is connected to the pipeline between the first water vapor compressor and the second water vapor compressor.

[0014] Optionally, the steam supply pipeline further includes a first liquid injection pipeline and a second liquid injection pipeline, the first liquid injection pipeline is connected to the compression chamber of the first water vapor compressor, and the second liquid injection pipeline is connected to the compression chamber of the second water vapor compressor.

[0015] Optionally, the steam supply pipeline further includes a steam bypass pipe, an input end of the steam bypass pipe is connected to an upstream pipeline of the first steam compressor, and an output end of the steam bypass pipe is connected to a downstream pipeline of the second steam compressor.

[0016] Optionally, the first heat pump circulation pipeline further includes a first air supply pipeline, an input end of the first air supply pipeline is connected to a downstream pipeline of the first condenser, and an output end of the first air supply pipeline is connected to a first compressor.

[0017] Optionally, the second heat pump circulation pipeline further includes a second air supply pipeline, an input end of the second air supply pipeline is connected to a downstream pipeline of the second condenser, and an output end of the second air supply pipeline is connected to a second compressor.

[0018] The heat pump steam supply system for self-circulating flash evaporation provided in the present application arranges the condenser of the cascade heat pump heating device in the flash tank, heats the water working medium in the flash tank by the condenser of the cascade heat pump heating device, fully utilizes the heat of the cascade heat pump heating device, reduces heat loss, can effectively increase the temperature of the flashed water working medium, and increases the flash evaporation amount; the water supply pipeline is heated by the condenser of the cascade heat pump heating device and then replenishes water into the flash tank, thereby increasing the temperature of the water supply, which not only reduces the influence of the excessively low water supply temperature on the system operation, but also reduces the system operation energy consumption. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the implementation of the present application, the following is a brief introduction to the relevant drawings. It is understood that the drawings described below are only used to illustrate some implementations of the present application, and those skilled in the art can also obtain many other technical features and connection relationships not mentioned in this document based on these drawings.

[0020] Figure 1 This is a schematic diagram of the structure of the heat pump steam supply system for self-circulating flash evaporation in this application;

[0021] Figure 2 A schematic top view of the spiral condensing coil of the present application;

[0022] Description of reference numerals:

[0023] 11. Waste heat inlet pipe; 12. First evaporator; 13. Waste heat outlet pipe; 14. First liquid return pipe; 15. First air inlet pipe; 16. First compressor; 17. First air outlet pipe; 18. First condenser; 19. First condensing pipe; 20. First expansion valve;

[0024] 21. Air supply pipe before the first valve; 22. First air supply expansion valve; 23. Air supply pipe after the first valve; 32. Second air inlet pipe; 33. Second compressor; 34. Second air outlet pipe; 35. Spiral condensing coil; 36. Second condensing pipe; 37. Second expansion valve; 38. Second liquid return pipe; 39. Air supply pipe before the second valve; 40. Second air supply expansion valve; 41. Air supply pipe after the second valve; 51. Water supply pump; 52. First water supply pipe; 53. First regulating valve; 54. Second water supply pipe; 61. Flash tank; 62. First stop valve; 63. First circulation pipe; 64. Circulating water pump; 65. Second circulation pipe; 66 , the second regulating valve; 67, the flash valve; 68, the flash liquid inlet pipe; 69, the flash pipe; 70, the second stop valve; 71, the drain pipe; 81, the first water vapor inlet pipe; 82, the third stop valve; 83, the first water vapor compressor; 84, the first water vapor exhaust pipe; 85, the steam cooler; 86, the second water vapor inlet pipe; 87, the second water vapor compressor; 88, the second water vapor exhaust pipe; 89, the third regulating valve; 90, the fourth regulating valve; 91, the water vapor bypass pipe; 92, the first liquid spray pipe; 93, the liquid spray pump; 94, the first liquid spray regulating valve; 95, the second liquid spray pipe; 96, the second liquid spray pump; 97, the second liquid spray regulating valve. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical solution and advantages of the embodiment of the utility model clearer, the technical solution in the embodiment of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiment of the utility model. Obviously, the described embodiment is a part of the embodiment of the utility model, not all of the embodiments. Based on the embodiment of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0026] In the description of the embodiments of the present utility model, it should be noted that the terms "center", "longitudinal", "lateral", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the embodiments of the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the embodiments of the present utility model. In addition, the terms "first", "second", and "third" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0027] In the description of the embodiments of the present utility model, it should be noted that, unless otherwise clearly specified and limited, the terms "connected" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the embodiments of the present utility model can be understood according to specific circumstances.

[0028] The technical solutions in the embodiments of the present application will be described in detail below in conjunction with the drawings in the embodiments of the present application.

[0029] The present embodiment provides a heat pump steam supply system for self-circulating flash evaporation, which includes a flash evaporation device, a cascade heat pump heating device, a water supply pipeline, and a steam supply pipeline.

[0030] like Figure 1 As shown, the flash evaporation device comprises a flash evaporation tank 61 and a flash evaporation circulation pipeline connecting the flash evaporation tank 61 .

[0031] The flash circulation pipeline includes a first circulation pipe 63, a second circulation pipe 65, a circulation water pump 64 and corresponding valve switches, wherein one end of the first circulation pipe 63 is connected to the output port at the bottom of the flash tank 61, and the other end of the first circulation pipe 63 is connected to the circulation water pump 64. A first stop valve 62 is arranged on the first circulation pipe 63, and the output end of the circulation water pump 64 is connected to the second circulation pipe 65. The second circulation pipe 65 is connected to a heat exchanger (the steam cooler 85 mentioned below), and then connected to the inside of the flash tank 61 through a flash liquid inlet pipe 68. A second regulating valve 66 and a flash valve 67 are arranged on the flash liquid inlet pipe 68; the flash liquid inlet pipe 68 is connected to a flash pipe 69 inside the flash tank 61.

[0032] The output end of the flash tank 61 is connected to a steam supply pipeline for processing the steam generated by the flash tank 61 and providing it to users.

[0033] The cascade heat pump heating device of this embodiment includes a first heat pump circulation pipeline and a second heat pump circulation pipeline.

[0034] like Figure 1 As shown, the first heat pump circulation pipeline includes a first evaporator 12, the inlet and outlet of one heat exchange side of the first evaporator 12 are respectively connected to the waste heat inlet pipe 11 and the waste heat outlet pipe 13, and the inlet and outlet of the other heat exchange side of the first evaporator 12 are respectively connected to the first liquid return pipe 14 and the first air inlet pipe 15. The first air inlet pipe 15 is connected to the first compressor 16, and the first compressor 16 is connected to the heat exchange side inlet of the first condenser 18 through the first air outlet pipe 17. The heat exchange side outlet of the first condenser 18 is connected to the first expansion valve 20 through the first condensation pipe 19, and the first expansion valve 20 is connected to the first liquid return pipe 14 to form a loop.

[0035] like Figure 1 As shown, the second heat pump circulation pipeline includes the first condenser 18 of the first heat pump circulation pipeline, the outlet of the heat exchange side of the first condenser 18 is connected to the second compressor 33 through the second air inlet pipe 32, the second compressor 33 is connected to the second condenser through the second air outlet pipe 34, the second condenser is connected to the second expansion valve 37 through the second condenser pipe 36, and the second expansion valve 37 is connected to the inlet of the heat exchange side of the first condenser 18 through the second liquid return pipe 38, thereby forming a loop of the second heat pump circulation pipeline.

[0036] It is worth mentioning that the second condenser of the second heat pump circulation pipeline in the present embodiment is arranged in the flash tank 61, and the second condenser is at least partially in contact with the liquid water in the flash tank 61. The second condenser is arranged in the flash tank 61, and the water working medium in the flash tank 61 is heated by the second condenser of the cascade heat pump heating device, so that the heat of the cascade heat pump heating device is fully utilized, the heat loss is reduced, the temperature of the flashed water working medium is effectively increased, and the flash evaporation amount is increased.

[0037] Further, such as Figure 1 and Figure 2 As shown, the second condenser in this embodiment can be configured as a spiral condensation coil 35, which is spirally arranged from the bottom of the flash tank 61 upward, fully contacts the water working medium in the flash tank 61, effectively heats the water working medium in the flash tank 61, and fully utilizes the heat of the cascade heat pump heating device.

[0038] In order to improve the heat exchange efficiency of the spiral condensing coil 35 , the spiral condensing coil 35 should be completely submerged in the water medium in the flash tank 61 .

[0039] like Figure 1 and Figure 2 As shown, in one embodiment, the radial dimension of the spiral circumference formed by the spiral condensing coil 35 gradually decreases from the bottom of the flash tank 61 to the top. That is to say, the spiral condensing coil 35 is a conical structure with a large bottom and a small top. In this way, the high-temperature working medium enters the spiral condensing coil 35 from the second outlet pipe 34 at the bottom, condenses and releases heat in the spiral condensing coil 35, and is discharged from the second condensing pipe 36 at the top. Since the spiral condensing coil 35 at the bottom of the flash tank 61 is larger, the heating range is wider and the heat exchange area is larger, so that the bottom heating temperature of the flash tank 61 is higher, so the bottom temperature of the flash tank 61 is higher in comparison. Since the water working medium inside the entire flash tank 61 is constantly flowing, the high-temperature water working medium at the bottom of the flash tank 61 continuously flows into the top of the flash tank 61 through the flash evaporation equipment, and flashes at reduced pressure inside. The water working medium that is not completely flashed and the supplementary working medium flow back to the bottom of the flash tank 61 together to be further heated. This design is conducive to increasing the temperature of the flashed water working medium and increasing the flash evaporation amount.

[0040] In one embodiment, Figure 1 As shown, the first heat pump circulation pipeline also has a first air supply pipeline, which includes a first valve front air supply pipe 21, a first air supply expansion valve 22 and a first valve rear air supply pipe 23. The first valve front air supply pipe 21 is connected to the first condenser 19, and is connected to the first valve rear air supply pipe 23 through the first air supply expansion valve 22. The first valve rear air supply pipe 23 is connected to the first compressor 16. The first air supply pipeline can achieve the effect of supplying air to the first compressor 16 to increase enthalpy.

[0041] Similarly, the second air supply pipeline includes a second air supply pipe 39 before the valve, a second air supply expansion valve 40 and a second air supply pipe 41 after the valve. The second air supply pipe 39 before the valve is connected to the second condenser 36, and is connected to the second air supply pipe 41 after the valve through the second air supply expansion valve 40. The second air supply pipe 41 after the valve is connected to the second compressor 33. The second air supply pipeline can also achieve the effect of increasing the enthalpy of the second compressor 33 by supplying air.

[0042] like Figure 1 As shown, the water replenishment pipeline of this embodiment includes a water replenishment pump 51, which is connected to an inlet of a heat exchange side of the first condenser 18 through a first water replenishment pipe 52, and then connected to the flash tank 61 from an outlet of a heat exchange side of the first condenser 18 through a second water replenishment pipe 54, so as to replenish water working medium inside the flash tank 61. A first regulating valve 53 is provided on the second water replenishment pipe 54.

[0043] In this embodiment, the first condenser 18 is a ternary condenser. The primary working fluid in the first heat pump circulation pipeline condenses and releases heat in the first condenser 18, which not only heats the secondary working fluid in the first heat pump circulation pipeline to make it evaporate, but also preheats the supplementary water from the first water supply pipe 52 to increase its temperature. The supplementary water preheated by the first condenser 18 is added to the flash tank 61, which not only reduces the impact of the low supplementary water temperature on the system operation, but also reduces the system's operating energy consumption.

[0044] like Figure 1 As shown, in this embodiment, the steam supply pipeline includes a first steam inlet pipe 81 connected to the steam output port of the flash tank 61, the first steam inlet pipe 81 is connected to the first steam compressor 83, a third stop valve 82 is provided on the first steam inlet pipe 81, the first steam compressor 83 is connected to the steam cooler 85 through the first steam exhaust pipe 84, the steam cooler 85 is connected to the second steam compressor 87 through the second steam inlet pipe 86, the second steam compressor 87 is connected to the user end through the second steam exhaust pipe 88 to provide steam for the user, and a third regulating valve 89 is provided on the second steam exhaust pipe 88.

[0045] In this embodiment, the inlet and outlet of one heat exchange side of the steam cooler 85 are respectively connected to the first water vapor exhaust pipe 84 and the second water vapor inlet pipe 86, and the inlet and outlet of the other heat exchange side of the steam cooler 85 are respectively connected to the second circulation pipe 65 and the flash liquid inlet pipe 68; the steam cooler 85 acts as a steam heat exchanger. On the one hand, it heats the water working medium from the flash tank 61 by the high-temperature steam flowing out of the first water vapor compressor 83, thereby increasing the temperature and flash volume of the flash water working medium. On the other hand, it can make full use of the heat of the high-temperature steam to effectively reduce the superheat of the water working medium flowing into the second water vapor compressor 87, thereby achieving the effect of two-stage compression and intermediate cooling.

[0046] like Figure 1 As shown, in this embodiment, the steam supply pipeline further comprises a first liquid injection pipeline and a second liquid injection pipeline, wherein the first liquid injection pipeline comprises a first liquid injection pipe 92, on which a first liquid injection pump 93 and a first liquid injection regulating valve 94 are provided, and the first liquid injection pipe 92 is connected to the compression chamber of the first water vapor compressor 83. The second liquid injection pipeline comprises a second liquid injection pipe 95, on which a second liquid injection pump 96 and a second liquid injection regulating valve 97 are provided, and the second liquid injection pipe 95 is connected to the compression chamber of the second water vapor compressor 87.

[0047] This embodiment uses the first liquid injection pipe 92 and the second liquid injection pipe 95 to respectively replenish water into the compression chambers of the first water vapor compressor 83 and the second water vapor compressor 87, thereby effectively reducing the exhaust superheat of the steam compressor, ensuring the safe and stable operation of the unit, and improving the performance of the steam compressor.

[0048] like Figure 1 As shown, the steam supply pipeline of this embodiment further includes a water vapor bypass pipe 91, the input end of the water vapor bypass pipe 91 is connected to the upstream pipeline of the first water vapor compressor 83, which can be connected to the flash tank 61 or connected to the first water vapor intake pipe 81, the output end of the water vapor bypass pipe 91 is connected to the downstream pipeline of the second water vapor compressor 87, which can be connected to the second water vapor exhaust pipe 88, and a fourth regulating valve 90 is provided on the water vapor bypass pipe 91. The water vapor bypass pipe 91 is used to directly supply the high-temperature and high-pressure steam in the flash tank 61 to the user.

[0049] In this embodiment, a sewage pipe 71 is further provided at the lower end of the flash tank 61. A second stop valve 70 is provided on the sewage pipe 71. The sewage pipe 71 is used to discharge sewage or supply the high-temperature water in the flash tank 61 to customers.

[0050] The specific working principle of this embodiment is as follows:

[0051] When the system of the embodiment of the present application is working normally, the cascade heat pump heating device works first, wherein the first heat pump circulation pipeline works, the waste heat flows into the first evaporator 12 through the waste heat inlet pipe 11, and then flows out through the waste heat outlet pipe 13, the first-level working fluid in the first evaporator 12 is heated, the first-level working fluid evaporates, and the evaporated first-level working fluid flows into the first compressor 16 through the first air inlet pipe 15 to be compressed, and then flows into the first condenser 18 through the first air outlet pipe 17, the first-level working fluid condenses in the first condenser 18 to release heat and heat the second-level working fluid in the second heat pump circulation pipeline to evaporate it, and at the same time, the supplementary water passing through the first condenser 18 is heated to make it warm. The temperature is increased, and a part of the condensed primary working fluid flows through the first condenser pipe 19, passes through the first expansion valve 20, expands, cools and reduces the pressure, and then flows back into the first evaporator 12 through the first return liquid pipe 14 to form a cycle. Another part flows through the first condenser pipe 19 and the first valve front air supply pipe 21, passes through the first air supply expansion valve 22, expands, cools and reduces the pressure, and then flows into the first compressor 16 through the first valve rear air supply pipe 23. In the first compressor 16, the superheat of the compressed primary working fluid is absorbed and evaporated. Then, it is compressed and discharged from the first compressor 16, and flows into the first condenser 18 through the first outlet pipe 17 to form a cycle, thereby achieving the effect of air supply and enthalpy increase.

[0052] The circulation paths of the second heat pump circulation pipeline and the first heat pump circulation pipeline are basically the same, and the difference is that the secondary working fluid absorbs the condensation heat of the primary working fluid in the first condenser 18 and evaporates, and condenses and releases heat in the spiral condensation coil 35 to heat the water working fluid in the flash tank 61 to increase its temperature, and the spiral condensation coil 35 is a spiral design, which is larger at the bottom and smaller at the top, which helps to increase the temperature of the water working fluid at the bottom of the flash tank 61, and the flash evaporation device takes water from the bottom of the flash tank 61 for flash evaporation. The higher the temperature of the water working fluid at the bottom, the more conducive it is to flash evaporation to produce steam.

[0053] The water replenishment pipeline of this embodiment is for the system to replenish water through the first condenser 18 of the cascade heat pump heating device to achieve temperature increase and then replenish water, thereby achieving high-temperature water replenishment inside the system and reducing the impact of low water replenishment temperature on system performance.

[0054] When the flash device is working, the first stop valve 62 and the second regulating valve 66 are opened, and the high-temperature water medium in the flash tank 61 flows through the first circulation pipe 63, the first stop valve 62 and the circulating water pump 64, and then flows into the steam cooler 85 through the second circulation pipe 65, is heated in the steam cooler 85, and then flows through the flash liquid inlet pipe 68, the second regulating valve 66 and the flash valve 67 into the flash pipe 69, and is flashed at the top of the flash tank 61 through the flash pipe 69 to reduce the pressure and form saturated steam and saturated water at a lower temperature.

[0055] There are two steam supply modes to choose from when the steam supply pipeline is working:

[0056] When the first steam supply mode is working, the third stop valve 82 and the third regulating valve 89 are opened, and the fourth regulating valve 90 is closed. The steam with lower temperature and pressure generated in the flash tank 61 flows through the first steam inlet pipe 81, through the third stop valve 82, and flows into the first steam compressor 83. After being compressed, the temperature and pressure are increased to reach a higher temperature and pressure. Then, it flows through the steam cooler 85 through the first steam exhaust pipe 84, and part of the steam is cooled and releases heat to heat the flash water working medium from the second circulation pipe 65 to increase its temperature. Then, it flows into the second steam compressor 87 through the second steam inlet pipe 86 to be compressed for the second time, further increasing the steam temperature and pressure to meet the demand for higher pressure and higher temperature steam.

[0057] When the first water vapor compressor 83 and the second water vapor compressor 87 are working, external supplementary water flows through the first liquid spray pipe 92, passes through the first liquid spray pump 93 and the first liquid spray regulating valve 94, and is sprayed into the compression chamber of the first water vapor compressor 83. Water is sprayed in the compression chamber to realize atomization and absorption of the temperature and pressure of the compressed water vapor, thereby reducing the exhaust superheat of the first water vapor compressor 83 and ensuring the safe and stable operation of the system.

[0058] Similarly, external make-up water flows through the second liquid spray pipe 95, passes through the second liquid spray pump 96 and the second liquid spray regulating valve 97, and is sprayed into the compression chamber of the second water vapor compressor 87. Water is sprayed in the compression chamber to achieve atomization and absorption of the temperature and pressure of the compressed water vapor, thereby reducing the exhaust superheat of the second water vapor compressor 87 and ensuring the safe and stable operation of the system.

[0059] In this process, the amount of water working medium injected can be adjusted by the first liquid injection regulating valve 94 and the second liquid injection regulating valve 97, so as to control the superheat of the exhaust gas of the first water vapor compressor 83 and the second water vapor compressor 87, on the one hand to ensure the superheat required for heating the water working medium in the steam cooler 85, and on the other hand to meet the superheat of the steam supply.

[0060] When the second steam supply mode is working, the third stop valve 82 is closed, the fourth regulating valve 90 and the third regulating valve 89 are opened, and the steam with lower temperature and pressure flows through the first steam inlet pipe 81, the steam bypass pipe 91 and the second steam exhaust pipe 88 through the fourth regulating valve 90 and the third regulating valve 89 to be supplied to users.

[0061] In the embodiments of the present invention, unless otherwise clearly specified and limited, the first feature being "above" or "below" the second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature being "above", "above" and "above" the second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. The first feature being "below", "below" and "below" the second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0062] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the utility model embodiment. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0063] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the utility model, rather than to limit it. Although the utility model has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the utility model.

Claims

1. A self-circulating flash heat pump steam supply system, characterized in that: include: A flash evaporation device, comprising a flash evaporation tank (61) and a flash evaporation circulation pipeline connected to the flash evaporation tank; A cascade heat pump heating device comprises a first heat pump circulation pipeline and a second heat pump circulation pipeline, wherein a heat exchange side of a first condenser (18) of the first heat pump circulation pipeline is connected to the second heat pump circulation pipeline, and the second condenser of the second heat pump circulation pipeline is arranged in the flash tank and at least partially contacts with liquid water in the flash tank; a water supply pipeline connected to the flash tank through the heat exchange side of the first condenser (18); The steam supply pipeline is connected to the output end of the flash tank and is used to process the steam generated by the flash tank.

2. The heat pump steam supply system of self-circulating flash evaporation according to claim 1 is characterized in that: The second condenser comprises a spiral condensation coil (35), wherein the spiral condensation coil (35) is spirally arranged upward from the bottom of the flash tank (61).

3. The heat pump steam supply system of self-circulating flash evaporation according to claim 2 is characterized in that: The radial dimension of the spiral circumference formed by the spiral condensing coil (35) gradually decreases from the bottom of the flash tank (61) upwards.

4. The heat pump steam supply system of self-circulating flash evaporation according to claim 3 is characterized in that: The spiral condensing coils (35) are all disposed in the liquid water in the flash tank (61).

5. The heat pump steam supply system for self-circulating flash evaporation according to any one of claims 1 to 4, characterized in that: The steam supply pipeline further comprises a first water vapor compressor (83) and a second water vapor compressor (87); the first water vapor compressor (83) is connected to the output end of the flash tank (61) via a pipeline, and the second water vapor compressor (87) is connected to a downstream pipeline of the first water vapor compressor (83).

6. The heat pump steam supply system of self-circulating flash evaporation according to claim 5, characterized in that: The steam supply pipeline further comprises a steam cooler (85), one heat exchange side of the steam cooler (85) being connected to the flash circulation pipeline, and the other heat exchange side of the steam cooler (85) being connected to the pipeline between the first water vapor compressor (83) and the second water vapor compressor (87).

7. The heat pump steam supply system of self-circulating flash evaporation according to claim 6, characterized in that: The steam supply pipeline further comprises a first liquid injection pipeline and a second liquid injection pipeline, the first liquid injection pipeline being connected to the compression chamber of the first water vapor compressor (83), and the second liquid injection pipeline being connected to the compression chamber of the second water vapor compressor (87).

8. The heat pump steam supply system of self-circulating flash evaporation according to claim 5, characterized in that: The steam supply pipeline further comprises a water vapor bypass pipe (91), the input end of the water vapor bypass pipe (91) being connected to an upstream pipeline of the first water vapor compressor (83), and the output end of the water vapor bypass pipe (91) being connected to a downstream pipeline of the second water vapor compressor (87).

9. The heat pump steam supply system for self-circulating flash evaporation according to any one of claims 1 to 4, characterized in that: The first heat pump circulation pipeline also includes a first air supply pipeline, the input end of the first air supply pipeline is connected to the downstream pipeline of the first condenser (18), and the output end of the first air supply pipeline is connected to the first compressor (16).

10. The heat pump steam supply system for self-circulating flash evaporation according to any one of claims 1 to 4, characterized in that: The second heat pump circulation pipeline also includes a second air supply pipeline, the input end of the second air supply pipeline is connected to the downstream pipeline of the second condenser, and the output end of the second air supply pipeline is connected to the second compressor (33).

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