A compact marine feedwater regeneration device and a ship steam power system

Abstract

The present invention discloses a compact marine feedwater regenerative device and a ship steam power system, which include an evaporator and a condenser, a generator, an absorber and a heat exchanger arranged circumferentially around the evaporator; the fresh solution distribution box in the generator is communicated with the absorber through the fresh solution pipeline in the heat exchanger, and the concentrated solution distribution box of the absorber is communicated with the generator through the concentrated solution pipeline in the heat exchanger; the evaporator is communicated with the propulsion steam turbine and the power generation steam turbine, and the evaporator is communicated with the absorber through a first steam pipeline, the generator is communicated with the condenser through a second steam pipeline, and the generator is communicated with the main evaporator. The compact marine feedwater regenerative device provided by the present invention uses the exhaust steam of the feed water pump driving steam turbine and the circulating water pump driving steam turbine as the high-temperature heat source, and the exhaust steam of the propulsion steam turbine and the power generation steam turbine as the low-temperature heat source, and can heat the feed water from 55 °C to about 95 °C, thereby increasing the feed water temperature entering the main evaporator, and further improving the working efficiency.

Description

Technical Field

[0001] The present invention relates to the field of ship steam power systems, and particularly to a compact marine feedwater regenerative device and a ship steam power system. Background Art

[0002] The ship steam power system is a core component of modern large ships, undertaking the tasks of propelling the ship forward and supplying electricity for the whole ship. The existing large ship steam power system adopts the steam Rankine cycle mode, and the steam power system mainly consists of main equipment such as marine boilers or reactors, propulsion steam turbines, power generation steam turbines, condensers, feedwater pumps, etc. However, due to the limited space in the ship power cabin and high reliability requirements, the system is relatively simplified, resulting in the problem of low system efficiency and insufficient economy of the ship steam power system.

[0003] Steam power systems in thermal power plants or nuclear power plants usually adopt measures such as increasing steam parameters, extraction regeneration, and intermediate reheat to improve efficiency, but the above measures are difficult to apply in the ship environment. For example: The parameters of the ship steam system need to balance multiple factors such as economy, safety, and reliability. Especially for nuclear-powered ships, limited by the working temperature of the pressurized water reactor, it is difficult to increase significantly anymore; The power station adopts a 5-8 stage extraction regenerative device or secondary intermediate reheat, and the system composition and pipelines are very complex, not only occupying a huge space, but also having a high maintenance difficulty and failure risk, and cannot be applied to large ships.

[0004] The thermal energy utilization efficiency of the ship steam power system is about 22 - 25%, and most of the heat will be carried into the condenser by the exhaust steam of the steam turbine and finally taken away by seawater. The heat taken away by the condenser accounts for more than 75% of the heat released by the marine boiler or reactor. How to reduce the heat discharged into the condenser is an important issue for improving the efficiency of the ship steam power system. Summary of the Invention

[0005] In view of the above technical defects and application requirements, embodiments of the present invention provide a compact marine feedwater regenerative device and a ship steam power system to effectively solve the existing problem of low thermal efficiency of the ship steam power system.

[0006] To solve the above problems, the present invention provides a compact marine feedwater regenerative device, including: an evaporator and a condenser, a generator, an absorber, and a heat exchanger arranged circumferentially around the evaporator;

[0007] The fresh solution distribution tank in the generator is connected to the absorber through the fresh solution pipeline in the heat exchanger, and the concentrated solution distribution tank of the absorber is connected to the generator through the concentrated solution pipeline in the heat exchanger; the evaporator is connected to the propulsion steam turbine and the power generation steam turbine, and the evaporator is connected to the absorber through the first steam pipeline, the generator is connected to the condenser through the second steam pipeline, the condenser is connected to the evaporator, the generator is connected to the main evaporator through the circulating water pump driving steam turbine and the feed water pump driving steam turbine, and the feed water pump is connected to the main evaporator through the absorber and the condenser.

[0008] Further, the absorber is provided with a first feed water heat exchange tube, a solution pump, a low-pressure steam inlet, a first concentrated solution inlet, a first fresh solution outlet, a first feed water inlet, and a first feed water outlet;

[0009] The low-pressure steam inlet is connected to the evaporator, the first concentrated solution inlet is connected to the concentrated solution pipeline, the first fresh solution outlet is connected to the fresh solution pipeline through the solution pump, the first feed water inlet is connected to the first feed water outlet through the first feed water heat exchange tube, the first feed water inlet is connected to the feed water pump, and the first feed water outlet is connected to the condenser.

[0010] Further, the generator is provided with a first fresh solution inlet, a first concentrated solution outlet, a medium-pressure steam outlet, a heat source steam inlet, a heat source steam heat exchange tube, and a heat source steam outlet;

[0011] The first fresh solution inlet is connected to the fresh solution pipeline, the first concentrated solution outlet is connected to the concentrated solution pipeline, the medium-pressure steam outlet is connected to the condenser, the heat source steam inlet is connected to the heat source steam outlet through the heat source steam heat exchange tube, the heat source steam inlet is connected to the main evaporator through the circulating water pump driving steam turbine and the feed water pump driving steam turbine, and the heat source steam outlet is connected to the deaerator.

[0012] Further, the condenser is provided with a throttle valve, a medium-pressure steam inlet, a medium-pressure steam box, a medium-pressure water outlet, a second feed water inlet, a second feed water heat exchange tube, and a second feed water outlet;

[0013] Both ends of the medium-pressure steam inlet are respectively connected to the medium-pressure steam box and the generator, the medium-pressure water outlet is connected to the evaporator through the throttle valve, the second feed water inlet is connected to the second feed water outlet through the second feed water heat exchange tube, the second feed water inlet is connected to the absorber, and the second feed water outlet is connected to the main evaporator.

[0014] Further, the evaporator is provided with an exhaust heat exchange tube, a low-pressure water header, a low-pressure water inlet, and a low-pressure steam outlet;

[0015] The exhaust heat exchange pipes are connected to the propulsion steam turbine and the power generation steam turbine. The low-pressure water header is connected to the condenser through the low-pressure water inlet, and the low-pressure steam outlet is connected to the absorber through the first steam pipe.

[0016] Furthermore, the heat exchanger is provided with a pressure reducing valve, a second dilute solution inlet, a second dilute solution outlet, a second concentrated solution inlet, and a second concentrated solution outlet. The second dilute solution inlet is connected to the absorber, the second dilute solution outlet is connected to the dilute solution distribution tank, the second concentrated solution inlet is connected to the generator, and the second concentrated solution outlet is connected to the concentrated solution distribution tank through the pressure reducing valve.

[0017] To solve the above problems, the present invention provides a ship steam power system, including: the above-mentioned compact marine feedwater regenerative device.

[0018] Furthermore, the ship steam power system further includes: a main evaporator, a propulsion steam turbine, a power generation steam turbine, a deaerator, a condenser, a feed water pump, a feed water pump driving steam turbine, a circulating water pump, and a circulating water pump driving steam turbine;

[0019] The output end of the main evaporator is respectively connected to the propulsion steam turbine, the power generation steam turbine, the feed water pump driving steam turbine, and the circulating water pump driving steam turbine. The propulsion steam turbine and the power generation steam turbine are sequentially connected through the evaporator, the condenser, the deaerator, the feed water pump, the absorber, the condenser, and the main evaporator. The feed water pump driving steam turbine and the circulating water pump driving steam turbine are sequentially connected through the generator, the deaerator, the feed water pump, the absorber, the condenser, and the main evaporator. The circulating water pump is connected to the condenser.

[0020] Furthermore, the compact marine feedwater regenerative device is installed on the condenser.

[0021] Furthermore, the exhaust steam pressure of the propulsion steam turbine and the power generation steam turbine is 0.01 - 0.03 MPa, and the exhaust steam temperature is 50 - 70 degrees Celsius.

[0022] The compact marine feedwater regenerative device and the ship steam power system provided by the present invention, by setting the compact marine feedwater regenerative device, using the exhaust steam of the feed water pump driving steam turbine and the circulating water pump driving steam turbine as the high-temperature heat source, and the exhaust steam of the propulsion steam turbine and the power generation steam turbine as the low-temperature heat source, can heat the feed water from 55°C to about 95°C, thereby increasing the feed water temperature entering the main evaporator, and further effectively improving the working efficiency of the ship steam power system. Description of the Drawings

[0023] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0024] Figure 1 Schematic structural diagram of the ship steam power system provided by the embodiment of the present invention;

[0025] Figure 2 Schematic external structure diagram of the compact marine feedwater regenerative device provided by the embodiment of the present invention;

[0026] Figure 3 Schematic internal structure diagram of the compact marine feedwater regenerative device provided by the embodiment of the present invention;

[0027] Figure 4 Schematic structure diagram of one side of the compact marine feedwater regenerative device provided by the embodiment of the present invention;

[0028] Figure 5 Schematic structure diagram of the other side of the compact marine feedwater regenerative device provided by the embodiment of the present invention;

[0029] Explanation of reference numerals: 1. Evaporator; 2. Condenser; 3. Generator; 4. Absorber; 5. Heat exchanger; 6. Propulsion steam turbine; 7. Power generation steam turbine; 8. Feed water pump drive steam turbine; 9. Circulating water pump drive steam turbine; 10. Main evaporator; 11. Feed water pump; 12. Deaerator; 13. Condenser; 14. Circulating water pump; 15. Compact marine feedwater regenerative device; 16. Exhaust steam heat exchange tube; 17. Low-pressure water header; 18. Low-pressure water inlet; 19. Low-pressure steam outlet; 21. Throttle valve; 22. Medium-pressure steam inlet; 23. Medium-pressure steam box; 24. Medium-pressure water outlet; 25. Second feed water inlet; 26. Second feed water heat exchange tube; 27. Second feed water outlet; 31. Dilute solution distribution box; 32. First dilute solution inlet; 33. First concentrated solution outlet; 34. Medium-pressure steam outlet; 35. Heat source steam inlet; 36. Heat source steam heat exchange tube; 37. Heat source steam outlet; 41. Concentrated solution distribution box; 42. First feed water heat exchange tube; 43. Solution pump; 44. Low-pressure steam inlet; 45. First concentrated solution inlet; 46. First dilute solution outlet; 47. First feed water inlet; 48. First feed water outlet; 51. Pressure reducing valve; 52. Second dilute solution inlet; 53. Second dilute solution outlet; 54. Second concentrated solution inlet; 55. Second concentrated solution outlet. Detailed implementation manners

[0030] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0031] In the description of the present invention, it should be noted that, unless otherwise clearly defined and limited, the terms "installed", "connected", and "connected" shall be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection or an electrical connection; it may be directly connected, or indirectly connected through an intermediate medium, and it may be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0032] An embodiment of the present invention provides a compact marine feedwater regenerative device, as Figure 1 , Figure 2 and Figure 3 shown. The compact marine feedwater regenerative device includes: an evaporator 1 and a condenser 2, a generator 3, an absorber 4, and a heat exchanger 5 arranged circumferentially around the evaporator 1, forming a structure centered on the evaporator 1.

[0033] Among them, the fresh solution distribution box 31 in the generator 3 is communicated with the absorber 4 through the fresh solution pipeline in the heat exchanger 5, and the concentrated solution distribution box 41 of the absorber 4 is communicated with the generator 3 through the concentrated solution pipeline in the heat exchanger 5; the evaporator 1 is communicated with a propulsion steam turbine 6 and a power generation steam turbine 7, and the evaporator 1 is communicated with the absorber 4 through a first steam pipeline, the generator 3 is communicated with the condenser 2 through a second steam pipeline, and the condenser 2 is communicated with the evaporator 1. The generator 3 is communicated with a main evaporator 10 through a circulating water pump-driven steam turbine 9 and a feed water pump-driven steam turbine 8, and the feed water pump 11 is communicated with the main evaporator 10 through the absorber 4 and the condenser 2.

[0034] During the working process of the compact marine feedwater regenerative device, the absorber 4 absorbs low-pressure steam with a concentrated refrigerant solution, changes the concentrated solution into a dilute solution, and releases heat at the same time. The low-pressure steam from the evaporator 1 at about 0.012 MPa and 50 °C enters the absorber 4, and the low-pressure steam forms a strong swirling flow with a large radial expansion ability, and then forms a strong energy and mass interaction with the downstream concentrated solution droplets at about 80 °C, which is beneficial to the rapid absorption of steam by the concentrated solution, thereby producing a dilute solution of the refrigerant.

[0035] The concentrated solution coming out of the heat exchanger 5 is depressurized and then converted into a concentrated solution at about 80°C and 0.019 MPa and enters the absorber 4. In the absorber 4, the concentrated solution first enters the concentrated solution distribution box 41, where it is distributed. To achieve a better absorption effect, the distributed concentrated solution is atomized and sprayed inside the absorber 4. The feed water from the feed water pump 11 enters to absorb the heat released during the process of the concentrated solution in the absorber 4 generating the dilute solution. The temperature of the dilute solution in the absorber 4 is about 70°C. The feed water can be initially heated by 5 - 10°C from 55°C and then leaves the absorber 4.

[0036] After the dilute solution coming out of the absorber 4 leaves, it is pumped by the solution pump from a low pressure of 0.012 MPa to a medium pressure of 0.21 MPa, and then enters the heat exchanger 5 to exchange heat with the concentrated solution from the generator 3. The temperature of the concentrated solution from the generator 3 is about 120°C, and the temperature of the dilute solution from the absorber 4 is about 70°C. The dilute solution absorbs heat and is heated to 110°C, and then leaves after the pressure is reduced to 0.207 MPa and enters the generator 3 again. While the concentrated solution is cooled to 80°C, and then after being depressurized to 0.019 MPa, it enters the absorber 4.

[0037] The dilute solution at about 110°C and 0.207 MPa from the heat exchanger 5 enters the dilute solution distribution box 31 of the generator 3, where it is distributed. The distributed dilute solution is atomized and sprayed inside the generator 3, and the pressure loss is about 0.007 MPa. The distributed dilute solution exchanges heat with the heat source steam sent by the circulating water pump driving the steam turbine 9 and the feed water pump driving the steam turbine 8. Since the temperature of the heat source steam is as high as 200°C, part of the water in the dilute solution droplets will evaporate into water vapor. The operating pressure in the generator 3 is maintained at about 0.2 MPa. The saturated steam and concentrated solution at about 120°C generated by the generator 3. The generated water vapor gathers at the top of the generator 3 under the action of buoyancy and then leaves the generator 3. The remaining dilute solution becomes a concentrated solution due to part of the water being evaporated, and the concentrated solution sinks downward and gathers in the lower half of the generator 3, and then leaves the generator 3 and enters the heat exchanger 5 to exchange heat with the dilute solution from the absorber 4. The concentrated solution releases heat and cools down and then leaves and enters the absorber 4 again.

[0038] The medium-pressure steam at 0.2 MPa generated by the generator 3 enters the condenser 2. The medium-pressure steam exchanges heat with the feed water sent by the feed water pump 11 and condenses into medium-pressure water. The pressure of the medium-pressure water is about 0.17 MPa and the temperature is about 95°C, and then it leaves the condenser 2 from the bottom of the condenser 2 and enters the evaporator 1. At the same time, the feed water enters the condenser 2 through the second feed water inlet 25 to absorb the heat released by the condensation of the medium-pressure steam, heats the feed water to above 95°C, and then enters the main evaporator 10.

[0039] Finally, the medium-pressure water is depressurized to low-pressure water and enters the evaporator 1, where it exchanges heat with the exhaust steam of the propulsion steam turbine 6 and the power generation steam turbine 7. The low-pressure water is evaporated into low-pressure steam at 0.012 MPa and 50 °C, and the generated low-pressure steam enters the absorber 4.

[0040] The compact marine feedwater regenerative device provided by the embodiment of the present invention can heat the feedwater from 55 °C to about 95 °C by setting up the compact marine feedwater regenerative device, taking the exhaust steam of the feedwater pump-driven steam turbine and the circulating water pump-driven steam turbine as the high-temperature heat source and the exhaust steam of the propulsion steam turbine and the power generation steam turbine as the low-temperature heat source. Thus, the temperature of the feedwater entering the main evaporator is increased, and the working efficiency of the ship steam power system is effectively improved.

[0041] Based on the above embodiment, in a preferred embodiment, as Figure 1 、 Figure 2 and Figure 3 shown, the absorber 4 is provided with a first feedwater heat exchange tube 42, a solution pump 43, a low-pressure steam inlet 44, a first concentrated solution inlet 45, a first dilute solution outlet 46, a first feedwater inlet 47 and a first feedwater outlet 48; the low-pressure steam inlet 44 is communicated with the evaporator 1, the first concentrated solution inlet 45 is communicated with the concentrated solution pipeline, the first dilute solution outlet 46 is communicated with the dilute solution pipeline through the solution pump 43, the first feedwater inlet 47 is communicated with the first feedwater outlet 48 through the first feedwater heat exchange tube 42, the first feedwater inlet 47 is communicated with the feedwater pump 11, and the first feedwater outlet 48 is communicated with the condenser 2.

[0042] Among them, the low-pressure steam inlet 44 receives the low-temperature and low-pressure steam from the evaporator 1, the first concentrated solution inlet 45 receives the low-temperature refrigerant concentrated solution after being cooled by the heat exchanger 5, the first dilute solution outlet 46 is used to discharge the refrigerant dilute solution generated by the absorber 4, the first feedwater inlet 47 receives the feedwater from the outlet of the feedwater pump 11, and the first feedwater outlet 48 is used to discharge the feedwater preliminarily heated by the absorber 4.

[0043] In this embodiment, the generator 3 is provided with a first dilute solution inlet 32, a first concentrated solution outlet 33, a medium-pressure steam outlet 34, a heat source steam inlet 35, a heat source steam heat exchange tube 36 and a heat source steam outlet 37. The first dilute solution inlet 32 is communicated with the dilute solution pipeline, the first concentrated solution outlet 33 is communicated with the concentrated solution pipeline, the medium-pressure steam outlet 34 is communicated with the condenser 2, the heat source steam inlet 35 is connected to the heat source steam outlet 37 through the heat source steam heat exchange tube 36, the heat source steam inlet 35 is communicated with the main evaporator 10 through the circulating water pump-driven steam turbine and the feedwater pump-driven steam turbine, and the heat source steam outlet 37 is communicated with the deaerator 12.

[0044] Among them, the first weak solution inlet 32 is used to receive the refrigerant weak solution that has been heated by heat recovery in the heat exchanger 5, the first strong solution outlet 33 is used to discharge the refrigerant strong solution generated by the generator 3, the medium-pressure steam outlet 34 is used to discharge the steam generated by the generator 3, the heat source steam inlet 35 is used to receive the exhaust steam of the feed water pump driving steam turbine 8 and the circulating water pump driving steam turbine 9, and the heat source steam outlet 37 is used to discharge the exhaust steam of the driving steam turbine after releasing heat in the generator 3.

[0045] In this embodiment, the condenser 2 is provided with a throttle valve 21, a medium-pressure steam inlet 22, a medium-pressure steam box 23, a medium-pressure water outlet 24, a second feed water inlet 25, a second feed water heat exchange tube 26, and a second feed water outlet 27. The two ends of the medium-pressure steam inlet 22 are respectively connected to the medium-pressure steam box 23 and the generator 3. The medium-pressure water outlet 24 is connected to the evaporator 1 through the throttle valve 21. The second feed water inlet 25 is connected to the second feed water outlet 27 through the second feed water heat exchange tube 26. The second feed water inlet 25 is connected to the absorber 4, and the second feed water outlet 27 is connected to the main evaporator 10.

[0046] Among them, the medium-pressure steam inlet 22 receives the medium-pressure steam generated by the generator 3. The medium-pressure water outlet 24 is used to discharge the condensed medium-pressure water into the evaporator 1. The second feed water inlet 25 is used to receive the feed water from the first feed water outlet 48. The second feed water outlet 27 is used to discharge the feed water heated by the condenser 2. The condenser 2 and the evaporator 1 adopt an integrated design. The bottom shell of the condenser 2 and the top shell of the evaporator 1 share the same shell to reduce the space requirement of the device. And two throttle valves 21 can be directly installed at the medium-pressure water outlet 24 to reduce the 0.15 MPa medium-pressure water to 0.02 MPa low-pressure water.

[0047] In this embodiment, the evaporator 1 is provided with an exhaust steam heat exchange tube 16, a low-pressure water header 17, a low-pressure water inlet 18, and a low-pressure steam outlet 19. The exhaust steam heat exchange tube 16 is connected to the propulsion steam turbine 6 and the power generation steam turbine 7. The low-pressure water header 17 is connected to the condenser 2 through the low-pressure water inlet 18. The low-pressure steam outlet 19 is connected to the absorber 4 through the first steam pipeline.

[0048] Among them, the low-pressure water inlet 18 is used to receive the low-pressure water after the medium-pressure water outlet 24 in the condenser 2 is depressurized by the throttle valve 21. The low-pressure steam outlet 19 is used to discharge the low-pressure steam generated by the evaporator 1.

[0049] In this embodiment, the heat exchanger 5 is provided with a pressure reducing valve 51, a second weak solution inlet 52, a second weak solution outlet 53, a second strong solution inlet 54, and a second strong solution outlet 55. The second weak solution inlet 52 is connected to the absorber 4 through a solution pump 43. The second weak solution outlet 53 is connected to the weak solution distribution tank 31. The second strong solution inlet 54 is connected to the generator 3. The second strong solution outlet 55 is connected to the strong solution distribution tank 41 through the pressure reducing valve 51.

[0050] Among them, the second weak solution inlet 52 receives the refrigerant weak solution from the absorber 4. The second strong solution inlet 54 is used to receive the refrigerant strong solution from the generator 3. The second weak solution outlet 53 discharges the weak solution after heat exchange and temperature rise. The second strong solution outlet 55 discharges the strong solution after heat exchange and temperature drop. Since the temperature of the strong solution generated by the generator 3 is relatively high, while the temperature of the weak solution generated by the absorber 4 is relatively low, the weak solution and the strong solution are subjected to heat exchange in the heat exchanger 5 to fully recover the heat of the strong solution.

[0051] As Figure 4 and Figure 5 shown, the compact marine feedwater regenerative device is arranged above the condenser 13. Among them, the evaporator 1 is in the central position. The lower left part is arranged with the absorber 4. The solution pump 43 is arranged on the side wall of the absorber 4. The upper right part is arranged with the generator 3. The condenser 2 is arranged on the top. The annular plate heat exchanger 5 is arranged near the outlet head. The evaporator 1 receives the exhaust steam from the propulsion steam turbine 6 and the power generation steam turbine 7. After passing through the inlet head of the evaporator 1, it enters the evaporation section. The evaporation section adopts a shell-and-tube structure. The exhaust steam flows on the tube side. After heat transfer, the slightly superheated steam becomes wet steam, and then enters the outlet head of the evaporator. On the one hand, considering that the wet steam may cause liquid accumulation in the outlet head. On the other hand, in order to minimize the flow resistance of the wet steam, in this embodiment, the outlet head and the condenser inlet are integrally designed, and the wet steam is introduced into the condenser 13 by the action of the wet steam flow and gravity.

[0052] During the working process of the compact marine feedwater regenerative device, the function of the absorber 4 is to absorb the low-pressure steam with the refrigerant strong solution, change the strong solution into a weak solution, and release heat at the same time. The low-pressure steam of about 0.012 MPa and 50 °C from the evaporator 1 enters the absorber through the low-pressure steam inlet 44. A swirl blade and an air flow expansion port are arranged at the low-pressure steam inlet, so that the low-pressure steam forms a strong swirl with a large radial expansion ability, and forms a strong energy and mass interaction with the droplets of the strong solution sprayed from the strong solution atomizing nozzle downstream of the low-pressure steam inlet 44, which is beneficial to the rapid absorption of steam by the strong solution to produce the refrigerant weak solution.

[0053] The concentrated solution flowing out from the second concentrated solution outlet 55 of the heat exchanger 5 passes through the pressure reducing valve 51. The concentrated solution at about 80°C and 0.019 MPa enters the absorber 4 through the first concentrated solution inlet 45. In the absorber 4, the concentrated solution first enters the concentrated solution distribution box 41, where it is distributed. The distributed concentrated solution then enters the concentrated solution atomizing nozzles respectively. The pressure loss from the first concentrated solution inlet 45 to the atomizing nozzles is about 0.007 MPa. This atomizing nozzle has the ability to atomize the continuous concentrated solution into small droplets, thereby increasing the absorption surface area of the concentrated solution. This atomizing nozzle sprays upward, forming a relative motion with the incoming low-pressure steam, extending the movement route of the small droplets, and thus achieving a better absorption effect.

[0054] The feed water from the feed water pump 11 enters the first feed water heat exchange tube 42 located below the free liquid level of the absorber 4 through the first feed water inlet 47, and absorbs the heat released during the process of generating fresh solution by the concentrated solution in the first feed water heat exchange tube 42. The temperature of the fresh solution in the absorber is about 70°C. The feed water can be initially heated from 55°C by 5 - 10°C and then leave the absorber 4 through the first feed water outlet 48.

[0055] After the fresh solution flowing out from the absorber 4 leaves through the first fresh solution outlet 46, it is pressurized from a low pressure of 0.012 MPa to a medium pressure of 0.21 MPa by the solution pump 43, and then enters the heat exchanger 5 to exchange heat with the concentrated solution from the generator 3. The temperature of the concentrated solution from the generator 3 is about 120°C, and the temperature of the fresh solution from the absorber 4 is about 70°C. The fresh solution absorbs heat and is heated to 110°C, and then leaves through the second fresh solution outlet 53 after the pressure is reduced to 0.207 MPa, and then enters the generator 3 through the first fresh solution inlet 32. After the concentrated solution is cooled to 80°C, it passes through the pressure reducing valve 51 to 0.019 MPa and then enters the first concentrated solution inlet 45 of the absorber 4. Since the maximum pressures of both the concentrated solution and the fresh solution do not exceed 0.3 MPa, and the maximum temperature does not exceed 130°C, the heat exchanger 5 adopts a microchannel plate heat exchanger structure to minimize the volume and weight of the heat exchanger 5 and meet the requirements of the semi-circular space structure.

[0056] Weak solution at approximately 110°C and 0.207 MPa from the second weak solution outlet 53 corresponding to the heat exchanger 5 enters the weak solution distribution box 31 of the generator 3 through the first weak solution inlet 32. After being distributed in the weak solution distribution box 31, it enters multiple weak solution atomizing nozzles. The pressure loss from the first weak solution inlet 32 to the atomizing nozzles is approximately 0.007 MPa. The small droplets of the weak solution ejected from the nozzles will wash the heat source steam heat exchange tubes 36. Since the temperature of the heat source steam is as high as 200°C, part of the water in the weak solution droplets will evaporate into water vapor. The operating pressure in the generator 3 is maintained at approximately 0.2 MPa, and saturated steam and strong solution at approximately 120°C are generated in the generator 3. The generated water vapor accumulates at the top of the generator 3 under the action of buoyancy and leaves the generator 3 through the medium-pressure steam outlet 34. The remaining weak solution becomes a strong solution because part of the water is evaporated, sinks downward and accumulates in the lower half of the generator 3, leaves the generator 3 through the first strong solution outlet 33, and then enters the heat exchanger 5 to exchange heat with the weak solution from the absorber 4. The strong solution releases heat and cools down, then leaves through the second strong solution outlet 55, and then enters the absorber 4 through the pressure reducing valve 51 and the first strong solution inlet 45.

[0057] The 0.2 MPa medium-pressure steam generated by the generator 3 enters the medium-pressure steam inlet 22 of the condenser 2 through the medium-pressure steam outlet 34, and then enters the medium-pressure steam box 23. Multiple steam injection holes are opened on the medium-pressure steam box 23 for injecting the medium-pressure steam into the condenser 2. The steam coming out of the steam injection holes laterally washes the second feed water heat exchange tubes 26 and then is all condensed into medium-pressure water. Considering the pressure loss caused by steam injection and condensation in the condenser 2, the pressure of this medium-pressure water is approximately 0.17 MPa and the temperature is approximately 95°C. It leaves the condenser 2 through the medium-pressure water outlet 24 at the bottom of the condenser 2. The feed water from the first feed water inlet 47 enters the second feed water heat exchange tubes 26 of the condenser 2 through the first feed water outlet 48, absorbs the heat released by the condensation of the medium-pressure steam in the second feed water heat exchange tubes 26, raises the temperature of the feed water to above 95°C, and then leaves the condenser 2 through the second feed water outlet 27 and then enters the main evaporator 10.

[0058] Finally, the low-pressure water after being depressurized by the throttle valve 21 enters the low-pressure water inlet 18 of the evaporator 1. After being distributed through the low-pressure water header 17, it enters multiple low-pressure water nozzles. Considering the pressure loss in this process is 0.008 MPa, the 0.012 MPa low-pressure water is ejected from the low-pressure water nozzles and washes the exhaust heat exchange tubes 16. The exhaust heat exchange tubes 16 contain the exhaust of the propulsion turbine 6 and the power generation turbine 7, and the temperature of the working fluid in the tubes is approximately 55°C. The exhaust releases heat in the exhaust heat exchange tubes 16 of the evaporator, evaporates the low-pressure water into low-pressure steam at 0.012 MPa and 50°C. The generated low-pressure steam is discharged from the low-pressure steam outlet 19 and then enters the absorber 4.

[0059] An embodiment of the present invention further provides a ship steam power system, as Figures 1 to 5 shown. The ship steam power system includes the above-mentioned compact marine feedwater regenerative device 15.

[0060] Among them, the ship steam power system further includes: a main evaporator 10, a propulsion steam turbine 6, a power generation steam turbine 7, a deaerator 12, a condenser 13, a feed water pump 11, a feed water pump driving steam turbine 8, a circulating water pump 14, and a circulating water pump driving steam turbine 9. The output end of the main evaporator 10 is respectively connected to the propulsion steam turbine 6, the power generation steam turbine 7, the feed water pump driving steam turbine 8, and the circulating water pump driving steam turbine 9. The propulsion steam turbine 6 and the power generation steam turbine 7 are sequentially connected through an evaporator 1, a condenser 13, a deaerator 12, a feed water pump 11, an absorber 4, a condenser 2, and the main evaporator 10; the feed water pump driving steam turbine 8 and the circulating water pump driving steam turbine 9 are sequentially connected through a generator 3, a deaerator 12, a feed water pump 11, an absorber 4, a condenser 2, and the main evaporator 10; the circulating water pump 14 is connected to the condenser 13. The compact marine feedwater regenerative device 15 is installed on the condenser 13.

[0061] In this embodiment, the main evaporator 10 in the ship steam power system absorbs heat from a marine boiler or a reactor to generate high-temperature and high-pressure steam at about 6 - 8 MPa. This steam is divided into three streams. The first stream enters the propulsion steam turbine 6 that drives the propeller, the second stream enters the power generation steam turbine 7 that drives the generator, and the third stream enters the feed water pump driving steam turbine 8 and the circulating water pump driving steam turbine 9 that drive the feed water pump 11 and the circulating water pump 14.

[0062] Among them, the exhaust steam pressures leaving the exhaust ports corresponding to the propulsion steam turbine 6 and the power generation steam turbine 7 are both 0.01 - 0.03 MPa, and the temperature is about 50 - 70 °C. In this embodiment, taking the exhaust steam parameters of 0.016 MPa and 55 °C as an example, the two streams of exhaust steam converge and enter the compact marine feedwater regenerative device 15 to release heat as a low-temperature heat source. This exhaust steam changes from slightly superheated saturated steam to wet steam, and after leaving the compact marine feedwater regenerative device 15, it enters the condenser 13 and is condensed into condensate.

[0063] The feed water pump 11 and the corresponding feed water pump driving steam turbine 8 of the circulating water pump 14 and the circulating water pump driving steam turbine 9 are both back pressure steam turbines. Their exhaust parameters are 0.2 - 0.3 MPa and the temperature is about 200 °C. This exhaust enters the compact marine feed water regenerative device 15 as a high-temperature heat source for heat release. Its exhaust changes from superheated steam to slightly superheated steam, and the temperature drops to about 140 - 150 °C. Then it enters the deaerator 12 at the lower part of the condenser 13 as the steam source for deaeration. After the steam in the condenser 13 condenses into water, it enters the feed water pump 11 after deaeration, boosting the condensate pressure from about 0.016 MPa to 6 MPa. Then it enters the compact marine feed water regenerative device 15 to absorb heat from the high-temperature heat source and the low-temperature heat source. Since the total heat of the high-temperature heat source is less and the temperature of the low-temperature heat source is lower than the condensate temperature, the compact marine feed water regenerative device 15 does not adopt the conventional shell-and-tube heat exchanger, but the absorption heat pump technology. When the high-temperature heat source exceeds 150 °C and the low-temperature heat source exceeds 55 °C, the condensate water at 55 °C can be heated to above 95 °C. Since the operating temperature of the bearings of the feed water pump 11 cannot exceed 85 °C, the feed water pump 11 must be arranged upstream of the compact marine feed water regenerative device 15. The 6 MPa and 95 °C feed water leaving the compact marine feed water regenerative device 15 enters the main evaporator 10, vaporizes into high-pressure and high-temperature steam in the main evaporator 10, and then enters the next cycle. Among them, the specific working process of the compact marine feed water regenerative device can refer to the Figures 1 to 5 text description above and will not be elaborated here.

[0064] In summary, for the ship steam power system provided in this embodiment, by setting up the compact marine feed water regenerative device, using the exhaust of the feed water pump driving steam turbine and the circulating water pump driving steam turbine as the high-temperature heat source, and the exhaust of the propulsion steam turbine and the power generation steam turbine as the low-temperature heat source, it can heat the feed water from 55 °C to about 95 °C, thereby raising the temperature of the feed water entering the main evaporator, and at the same time reducing the waste heat emission in the condenser, and thus effectively improving the working efficiency of the ship steam power system. In addition, this ship steam power system also has the following advantages:

[0065] First, this ship steam power system can reduce the thermal power of the boiler or reactor by 10% when the outlet temperature of the main evaporator remains unchanged, and thus can increase the system efficiency from the current 22% - 25% to 25% - 28%.

[0066] Second, due to the increase in system efficiency, the rated heat load of the condenser and the circulating water demand are both significantly reduced, which can significantly reduce the volume of the condenser and at the same time reduce the power of the circulating water pump.

[0067] Third, the reduction of the condenser can effectively make up for the volume of the newly added feed water regenerative device and will not increase the volume of the additional ship steam power system.

[0068] Fourth, the internal of the compact marine feedwater regeneration device provided in this embodiment is a complete closed cycle, with good compactness and reliability.

[0069] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the invention and are not intended to limit them. Although the invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some of the technical features. These modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the invention.

Claims

1. A compact marine feedwater regenerative device, characterized in that, Comprising: An evaporator, and a condenser, a generator, an absorber and a heat exchanger arranged circumferentially of the evaporator; The fresh solution distribution tank in the generator is communicated with the absorber through the fresh solution pipeline in the heat exchanger, and the concentrated solution distribution tank of the absorber is communicated with the generator through the concentrated solution pipeline in the heat exchanger; the evaporator is communicated with a propulsion steam turbine and a power generation steam turbine, and the evaporator is communicated with the absorber through a first steam pipeline, the generator is communicated with the condenser through a second steam pipeline, the condenser is communicated with the evaporator, the generator is communicated with a main evaporator through a circulating water pump-driven steam turbine and a feed water pump-driven steam turbine, and the feed water pump is communicated with the main evaporator through the absorber and the condenser; During operation, the absorber absorbs low-pressure steam with a refrigerant concentrated solution; the concentrated solution coming out of the heat exchanger enters the absorber, and in the absorber, the concentrated solution first enters the concentrated solution distribution tank, and the distributed concentrated solution is atomized and sprayed in the absorber; after the fresh solution coming out of the absorber leaves, it enters the heat exchanger to exchange heat with the concentrated solution coming from the generator; the fresh solution coming from the heat exchanger enters the fresh solution distribution tank of the generator, is distributed in the fresh solution distribution tank, and the distributed fresh solution is atomized and sprayed in the generator; the distributed fresh solution exchanges heat with the heat source steam fed by both the circulating water pump-driven steam turbine and the feed water pump-driven steam turbine, the saturated steam and the concentrated solution generated by the generator leave the generator, the remaining fresh solution sinks downward and accumulates in the lower half of the generator, and then leaves the generator and enters the heat exchanger again to exchange heat with the fresh solution coming from the absorber, the concentrated solution releases heat and cools down and then leaves, and then enters the absorber; the medium-pressure steam of the generator enters the condenser, and then enters the evaporator through the condenser; the feed water enters the condenser to absorb the heat released by the condensation of the medium-pressure steam, raises the temperature of the feed water to above 95°C, and then enters the main evaporator; finally, the medium-pressure water is depressurized into low-pressure water and enters the evaporator, exchanges heat with the exhaust steam of both the propulsion steam turbine and the power generation steam turbine in the evaporator, and the generated low-pressure steam enters the absorber; The absorber is provided with a first feed water heat exchange tube, a solution pump, a low-pressure steam inlet, a first concentrated solution inlet, a first fresh solution outlet, a first feed water inlet and a first feed water outlet; the low-pressure steam inlet is communicated with the evaporator, the first concentrated solution inlet is communicated with the concentrated solution pipeline, the first fresh solution outlet is communicated with the fresh solution pipeline through the solution pump, the first feed water inlet is communicated with the first feed water outlet through the first feed water heat exchange tube, the first feed water inlet is communicated with the feed water pump, and the first feed water outlet is communicated with the condenser; The generator is provided with a first dilute solution inlet, a first concentrated solution outlet, a medium-pressure steam outlet, a heat source steam inlet, heat source steam heat exchange tubes, and a heat source steam outlet; the first dilute solution inlet is communicated with the dilute solution pipeline, the first concentrated solution outlet is communicated with the concentrated solution pipeline, the medium-pressure steam outlet is communicated with the condenser, the heat source steam inlet is connected to the heat source steam outlet through the heat source steam heat exchange tubes, the heat source steam inlet is communicated with the main evaporator through the circulating water pump-driven steam turbine and the feed water pump-driven steam turbine, and the heat source steam outlet is communicated with the deaerator.

2. The compact marine feedwater regeneration device according to claim 1, characterized in that, The condenser is provided with a throttle valve, a medium-pressure steam inlet, a medium-pressure steam box, a medium-pressure water outlet, a second feed water inlet, second feed water heat exchange tubes, and a second feed water outlet; Both ends of the medium-pressure steam inlet are respectively communicated with the medium-pressure steam box and the generator, the medium-pressure water outlet is communicated with the evaporator through the throttle valve, the second feed water inlet is communicated with the second feed water outlet through the second feed water heat exchange tubes, the second feed water inlet is communicated with the absorber, and the second feed water outlet is communicated with the main evaporator.

3. The compact marine feedwater regeneration device according to claim 1, characterized in that, The evaporator is provided with exhaust steam heat exchange tubes, a low-pressure water header, a low-pressure water inlet, and a low-pressure steam outlet; The exhaust steam heat exchange tubes are communicated with the propulsion steam turbine and the power generation steam turbine, the low-pressure water header is communicated with the condenser through the low-pressure water inlet, and the low-pressure steam outlet is communicated with the absorber through the first steam pipeline.

4. The compact marine feedwater regeneration device according to claim 1, characterized in that, The heat exchanger is provided with a pressure reducing valve, a second dilute solution inlet, a second dilute solution outlet, a second concentrated solution inlet, and a second concentrated solution outlet; The second dilute solution inlet is communicated with the absorber, the second dilute solution outlet is communicated with the dilute solution distribution box, the second concentrated solution inlet is communicated with the generator, and the second concentrated solution outlet is communicated with the concentrated solution distribution box through the pressure reducing valve.

5. A ship steam power system, characterized in that, Comprising: The compact marine feed water regenerative device according to any one of claims 1-4.

6. The ship steam power system according to claim 5, wherein, The ship steam power system further includes: A main evaporator, a propulsion steam turbine, a power generation steam turbine, a deaerator, a condenser, a feed water pump, a feed water pump-driven steam turbine, a circulating water pump, and a circulating water pump-driven steam turbine; The output end of the main evaporator is respectively communicated with the propulsion steam turbine, the power generation steam turbine, the feed water pump-driven steam turbine, and the circulating water pump-driven steam turbine. The propulsion steam turbine and the power generation steam turbine are sequentially communicated through the evaporator, the condenser, the deaerator, the feed water pump, the absorber, the condenser, and the main evaporator; the feed water pump-driven steam turbine and the circulating water pump-driven steam turbine are sequentially communicated through the generator, the deaerator, the feed water pump, the absorber, the condenser, and the main evaporator; the circulating water pump is communicated with the condenser.

7. The ship steam power system according to claim 6, characterized in that, The compact marine feed water regenerative device is installed on the condenser.

8. The ship steam power system according to claim 6, characterized in that, The exhaust steam pressures of the propulsion steam turbine and the power generation steam turbine are 0.01-0.03 MPa, and the exhaust steam temperatures are 50-70 degrees Celsius.

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