Low-temperature heating reactor multi-pressure steam supply system

Abstract

The present invention relates to a low-temperature heating reactor multi-pressure steam supply system, comprising a low-temperature heating reactor, a first steam generator, a second steam generator, an intermediate loop, reheating units and a replenished water treatment unit. The low-temperature heating reactor, a primary side of the first steam generator, and a primary side of the second steam generator are arranged on the intermediate loop; a secondary side of the first steam generator and a secondary side of the second steam generator utilize heat energy generated by the low-temperature heating reactor to respectively produce first initial saturated steam and second initial saturated steam; the reheating units are connected to the secondary side of the first steam generator and the secondary side of the second steam generator, and reheats the first initial saturated steam and the second initial saturated steam to produce medium-pressure superheated steam and low-pressure superheated steam; and the replenished water treatment unit is connected to the secondary side of the first steam generator and the secondary side of the second steam generator, so as to use the initial saturated steam to heat and deoxidize replenished water of the two steam generators. According to the present invention, low-pressure superheated steam and medium-pressure superheated steam can be produced by means of the low-temperature heating reactor.

Description

Multi-pressure steam supply system for low-temperature heating reactor Technical Field

[0001] The present invention relates to the technical field of nuclear energy application, and in particular to a multi-pressure steam supply system for a low-temperature heating reactor. Background Art

[0002] Low-temperature heating reactors (LTHRs) are increasingly popular among industrial users due to their low cost, high safety and reliability, mature technology, stable operation, and easy maintenance. They are primarily used in the industrial sector for heat and steam supply. However, the existing technologies for LTRs are limited in their thermal energy output, typically only providing low-pressure superheated steam below 1.6 MPa. They are unable to provide steam at higher pressures, thus failing to meet user demands for medium- and high-pressure superheated steam. This has limited their application. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to provide a multi-pressure steam supply system for a low-temperature heating reactor.

[0004] The technical solution adopted by the present invention to solve the technical problem is: constructing a low-temperature heating reactor multi-pressure steam supply system, including a low-temperature heating reactor, a first steam generator, a second steam generator, an intermediate circuit, a reheat unit and a water supply treatment unit;

[0005] The low-temperature heating reactor, the primary side of the first steam generator, and the primary side of the second steam generator are respectively arranged on the intermediate loop, and the secondary sides of the first steam generator and the second steam generator respectively produce first initial saturated steam and second initial saturated steam using the heat energy generated by the low-temperature heating reactor;

[0006] The reheat unit is connected to the secondary side of the first steam generator and the secondary side of the second steam generator, and reheats the first and second initial saturated steam to produce medium-pressure superheated steam and low-pressure superheated steam;

[0007] The make-up water processing unit is connected to the secondary sides of the first steam generator and the second steam generator to heat and deoxygenate the make-up water of the two steam generators using initial saturated steam.

[0008] Preferably, the water replenishment processing unit includes a first sub-water replenishment processing unit and a second sub-water replenishment processing unit;

[0009] The first sub-water replenishment treatment unit has a steam inlet connected to the secondary side steam outlet of the first steam generator or the secondary side steam outlet of the second steam generator, and a replenishment water outlet connected to the secondary side replenishment water inlet of the first steam generator. The replenishment water inlet is used to receive replenishment water to heat and deoxygenate the replenishment water using initial saturated steam;

[0010] The steam inlet of the second sub-make-up water treatment unit is connected to the secondary side steam outlet of the first steam generator or the secondary side steam outlet of the second steam generator, and the make-up water outlet is connected to the secondary side make-up water inlet of the second steam generator. The make-up water inlet is used to receive make-up water to heat and deoxygenate the make-up water using initial saturated steam.

[0011] Preferably, the first sub-water replenishment treatment unit includes a first deaerator, a first regulating valve and a first booster pump;

[0012] The water supply inlet of the first deaerator is used to receive water supply, the steam inlet of the first deaerator is connected to the secondary steam outlet of the first steam generator or the secondary steam outlet of the second steam generator via the first regulating valve, and the water supply outlet of the first deaerator is connected to the secondary water supply inlet of the first steam generator via the first booster pump;

[0013] The second sub-water replenishment treatment unit includes a second deaerator, a second regulating valve and a second booster pump;

[0014] The water make-up inlet of the second deaerator is used to connect make-up water, the steam inlet of the second deaerator is connected to the secondary side steam outlet of the first steam generator or the secondary side steam outlet of the second steam generator through the second regulating valve, and the water make-up outlet of the second deaerator is connected to the secondary side make-up water inlet of the second steam generator through the second booster pump.

[0015] Preferably, the temperature range of the feed water heated by the first deaerator is 145-201° C.; and / or the temperature range of the feed water heated by the second deaerator is 135-155° C.

[0016] Preferably, the water replenishment treatment unit further includes a fifth regulating valve and a sixth regulating valve;

[0017] The fifth regulating valve is connected between the second boost pump and the secondary side water supply inlet of the second steam generator. The connection node between the second boost pump and the fifth regulating valve is also connected to the water supply inlet of the first deaerator through the sixth regulating valve.

[0018] Preferably, the low-temperature heating reactor includes a nuclear reactor, a heat exchanger and a circulation pump;

[0019] The secondary side outlet of the heat exchanger is connected to the secondary side inlet of the heat exchanger via the primary side of the first steam generator, the primary side of the second steam generator and the circulation pump in sequence. The heat exchanger cooperates with the nuclear reactor to utilize the heat energy generated by the nuclear reactor to heat the circulating water in its secondary side.

[0020] Preferably, the gas pressure range of the low-pressure superheated steam is 0.8~1.8 MPa.a; and / or the gas pressure range of the medium-pressure superheated steam is 2.2~3.2 MPa.a.

[0021] Preferably, the first steam generator is provided on an upstream pipeline of the intermediate loop, and the second steam generator is provided on a downstream pipeline of the first steam generator.

[0022] Preferably, the water temperature at the primary water inlet of the first steam generator is maintained at 248+T1°C; and / or the water temperature at the primary water inlet of the second steam generator is maintained at 234+T2°C, and the water temperature at the primary water outlet of the second steam generator is maintained at 208+T3°C; wherein the ranges of T1, T2 and T3 are -4~+4°C respectively.

[0023] Optionally, the water makeup treatment unit includes a fifth deaerator, a seventh regulating valve and a sixth booster pump;

[0024] The water make-up inlet of the fifth deaerator is used to connect make-up water, the steam inlet of the fifth deaerator is connected to the secondary side steam outlet of the first steam generator or the secondary side steam outlet of the second steam generator through the seventh regulating valve, the water make-up outlet of the fifth deaerator is connected to one end of the sixth booster pump, and the other end of the sixth booster pump is connected to the secondary side make-up water inlet of the first steam generator and the secondary side make-up water inlet of the second steam generator.

[0025] Preferably, the low-temperature heating reactor multi-pressure steam supply system further includes a high-pressure superheated steam pretreatment unit;

[0026] The water supply inlet of the high-pressure superheated steam pretreatment unit is connected to the desalted water, and the steam inlet of the high-pressure superheated steam pretreatment unit is connected to the secondary side of the first steam generator and the secondary side of the second steam generator, so as to utilize the first initial saturated steam and the second initial saturated steam to heat and deoxygenate the desalted water and then transport it to the reheat unit;

[0027] The reheat unit further reheats the desalted water after heating and deoxygenation to produce high-pressure superheated steam.

[0028] Preferably, the high-pressure superheated steam pretreatment unit includes a third deaerator, a third regulating valve, a third booster pump, a fourth deaerator and a fourth regulating valve;

[0029] The steam inlet of the third deaerator is connected to the secondary side steam outlet of the second steam generator through the third regulating valve, the make-up water inlet of the third deaerator is connected to the desalted water, the make-up water outlet of the third deaerator is connected to the make-up water inlet of the fourth deaerator through the third booster pump, the make-up water outlet of the fourth deaerator is connected to the reheat unit, and the steam inlet of the fourth deaerator is connected to the secondary side steam outlet of the first steam generator through the fourth regulating valve.

[0030] Preferably, the high-pressure superheated steam pretreatment unit further includes a fourth booster pump connected between the make-up water outlet of the fourth deaerator and the reheat unit.

[0031] Preferably, the pressure range of the high-pressure superheated steam is 3.5~11 MPa.a.

[0032] Preferably, the pipeline connecting the first deaerator and the second deaerator to the water supply equipment passes through the reheat unit, so that the reheat unit heats the water supply input to the first deaerator and the second deaerator.

[0033] Preferably, the low-temperature heating reactor multi-pressure steam supply system further includes a fifth booster pump;

[0034] The outlet of the fifth booster pump is connected to the water supply inlet of the first deaerator, and the inlet of the fifth booster pump is connected to the water supply inlet of the second deaerator on one side and is connected to the water supply equipment through a pipeline passing through the reheat unit on the other side.

[0035] Preferably, the reheat unit is a gas-fired oil-fired boiler, a molten salt heat exchanger, a gas turbine flue gas waste heat boiler, a thermal power plant boiler, an electric heater or a gas heater.

[0036] The implementation of the present invention has the following beneficial effects: it provides a multi-pressure steam supply system for a low-temperature heating reactor; heat energy is generated by the low-temperature heating reactor, so that the first steam generator and the second steam generator use the heat supply of the low-temperature heating reactor to produce a first initial saturated steam and a second initial saturated steam respectively, and when producing the two initial saturated steams, the make-up water of the two steam generators is also heated and deoxygenated by the make-up water treatment unit, so that the two steam generators can better generate steam with higher temperature and pressure, and the increase in the make-up water temperature can also prevent the circulating water on the primary side of the two steam generators from dropping too much in temperature after heat exchange, affecting the normal operation of the low-temperature heating reactor 1, and then the initial saturated steam produced by the first steam generator and the second steam generator is further heated by the reheating unit to obtain medium-pressure superheated steam and low-pressure superheated steam, thereby achieving the technical effect of the low-temperature heating reactor providing medium-pressure superheated steam, and at the same time meeting the user's needs for low-pressure superheated steam and medium-pressure superheated steam. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] The present invention will be further described below with reference to the accompanying drawings and embodiments, in which:

[0038] FIG1 is a schematic structural diagram of a first embodiment of a multi-pressure steam supply system for a low-temperature heating reactor according to the present invention;

[0039] FIG2 is a schematic structural diagram of a second embodiment of a multi-pressure steam supply system for a low-temperature heating reactor according to the present invention;

[0040] FIG3 is a schematic structural diagram of a third embodiment of a multi-pressure steam supply system for a low-temperature heating reactor according to the present invention;

[0041] FIG4 is a structural diagram of a fourth embodiment of a multi-pressure steam supply system for a low-temperature heating reactor according to the present invention. DETAILED DESCRIPTION

[0042] In order to have a clearer understanding of the technical features, purposes and effects of the present invention, specific embodiments of the present invention are now described in detail with reference to the accompanying drawings.

[0043] Figure 1 is a schematic diagram of a multi-pressure steam supply system for a low-temperature heating reactor, according to some embodiments of the present invention. This system utilizes the low-temperature heating reactor to produce not only low-pressure superheated steam but also steam at sub-intermediate pressures and above. As shown in Figure 1 , the steam supply system includes a low-temperature heating reactor 1, a first steam generator 2, a second steam generator 3, an intermediate circuit 4, a reheat unit 5, and a makeup water treatment unit 6.

[0044] Referring to Figure 1 , the low-temperature heating reactor 1, the primary side of the first steam generator 2, and the primary side of the second steam generator 3 are each arranged on an intermediate loop 4. The secondary sides of the first steam generator 2 and the second steam generator 3 utilize the heat energy generated by the low-temperature heating reactor 1 to produce first and second initial saturated steam, respectively. A reheat unit 5 is connected to the secondary sides of the first steam generator 2 and the second steam generator 3 to reheat the first and second initial saturated steam, thereby producing medium-pressure superheated steam and low-pressure superheated steam. A feed water treatment unit 6 is connected to the secondary sides of the first steam generator 2 and the second steam generator 3 to use the initial saturated steam to heat and deoxygenate the feed water for both steam generators.

[0045] Optionally, the pressure range of the low-pressure superheated steam is 0.8-1.8 MPa.a, and the pressure range of the medium-pressure superheated steam is 2.2-3.2 MPa.a. Furthermore, the pressure of the low-pressure superheated steam is preferably 1.5 MPa.a, so that the superheat temperature of the low-pressure superheated steam can reach 260°C; accordingly, the pressure of the second initial saturated steam is preferably 1.6 MPa.a, so that the saturation temperature of the second initial saturated steam can reach 201°C. The pressure of the medium-pressure superheated steam is preferably 2.7 MPa.a, so that the superheat temperature of the medium-pressure superheated steam can reach 326°C; accordingly, the pressure of the first initial saturated steam is preferably 2.8 MPa.a, so that the saturation temperature of the first initial saturated steam can reach 230°C.

[0046] It should be noted that the first steam generator 2 generates first initial saturated steam, which is heated by the reheat unit 5 to produce medium-pressure superheated steam. The second steam generator 3 generates second initial saturated steam, which is reheated to produce low-pressure superheated steam. Furthermore, the initial saturated steam required for heating and deoxygenation in the makeup water treatment unit 6 can be either the first initial saturated steam or the second initial saturated steam. Furthermore, the first steam generator 2 and the second steam generator 3 can be existing steam generators. The steam production principle is the same as that of steam generators in existing nuclear power plants and will not be further described here.

[0047] It should be noted that if the temperature of the make-up water to be vaporized into initial saturated steam is low, greater heat energy will be required for the vaporization of the make-up water. This will result in the steam pressure and temperature that can be generated by the steam generator (i.e., the first steam generator 2 and the second steam generator 3) being limited. Generally, only low-pressure superheated steam can be generated, which cannot meet the steam supply requirements of high steam pressure. However, this embodiment produces thermal energy through the low-temperature heating stack 1, so that the first steam generator 2 and the second steam generator 3 use the heat supply of the low-temperature heating stack 1 to produce the first initial saturated steam and the second initial saturated steam respectively. When producing the two initial saturated steams, the make-up water of the two steam generators is also heated and deoxygenated by the make-up water treatment unit so that the two steam generators can better produce steam with higher temperature and pressure. The increase in the make-up water temperature can also prevent the circulating water on the primary side of the two steam generators from dropping too much in temperature after heat exchange, affecting the normal operation of the low-temperature heating stack 1. Then, the initial saturated steam produced by the first steam generator 2 and the second steam generator 3 is further heated by the reheat unit 5, thereby obtaining medium-pressure superheated steam and low-pressure superheated steam, thereby achieving the technical effect of the low-temperature heating stack providing medium-pressure superheated steam, and at the same time meeting the user's needs for low-pressure superheated steam and medium-pressure superheated steam.

[0048] In some embodiments, as shown in FIG1 , a low-temperature heating reactor 1 includes a nuclear reactor 11, a heat exchanger 12, and a circulation pump 13. The secondary side outlet of the heat exchanger 12 is connected to the secondary side inlet of the heat exchanger 12 via the primary side of the first steam generator 2, the primary side of the second steam generator 3, and the circulation pump 13. The heat exchanger 12 cooperates with the nuclear reactor 11 to utilize the heat energy generated by the nuclear reactor 11 to heat the circulating water in the secondary side of the heat exchanger 12.

[0049] In this embodiment, nuclear reactor 11 may be an existing low-power reactor, and its heat generation principle may refer to existing technologies. The primary side of heat exchanger 12 is used to absorb the heat energy generated by nuclear reactor 11 to heat the circulating water in its secondary side, while the circulating pump 13 is used to provide power for the circulating water to circulate in intermediate loop 4. Alternatively, heat exchanger 12 may be an existing nuclear power plant heat exchanger.

[0050] In some embodiments, the intermediate loop 4 comprises a closed loop of pipes, providing a circulation loop for the circulating water. It is understood that since the circulating water on the primary side of the two steam generators transfers heat to the secondary side as it flows, the closer it is to the secondary outlet of the heat exchanger 12, the higher the circulating water temperature. Therefore, the first steam generator 2 can be positioned upstream of the intermediate loop 4 so that the circulating water output from the intermediate loop 4 reaches the first steam generator 2 first, allowing the first steam generator 2 to produce steam using the higher-temperature circulating water. This allows the first steam generator 2 to generate steam using the higher-temperature circulating water, further facilitating the generation of higher-temperature first initial saturated steam, which can then be heated to medium-pressure superheated steam. Since the second initial saturated steam produced by the second steam generator 3 ultimately generates low-pressure superheated steam, the steam temperature and pressure requirements are relatively low. Therefore, the upstream circulating water, after being cooled by the first steam generator 2, is sufficient to participate in the steam production of the second steam generator 3. Therefore, the second steam generator 3 can be positioned downstream of the first steam generator 2. Furthermore, the circulating water will be further cooled after passing through the second steam generator 3, which will cause the circulating water temperature in the upstream pipeline to be higher than the circulating water temperature in the downstream pipeline. This is equivalent to forming a high-temperature section pipeline from the water outlet on the secondary side of the heat exchanger 12 to the water inlet on the primary side of the first steam generator 2, and a low-temperature section pipeline from the water outlet on the primary side of the first steam generator 2 to the water inlet on the primary side of the second steam generator 3 on the primary side of the two steam generators in the intermediate loop 4.

[0051] It can be understood that the quality of the medium-pressure superheated steam and low-pressure superheated steam ultimately produced by the reheat unit 5 is closely related to the pressure and temperature of the corresponding initial saturated steam. In this embodiment, by arranging the first steam generator 2 on the upstream pipeline and the second steam generator 3 on the downstream pipeline, on the one hand, the pressure and temperature of the first initial saturated steam of the first steam generator 2 can be made higher, which is more convenient for reheating into medium-pressure superheated steam. On the other hand, the thermal energy of the circulating water after heat exchange and cooling by the first steam generator 2 is also sufficient to enable the second steam generator 3 to produce second initial saturated steam with relatively low pressure and temperature. After reheating the second initial saturated steam, low-pressure superheated steam can be obtained. That is, such an arrangement can more reasonably utilize the circulating water heated by the low-temperature heating stack 1 to generate steam.

[0052] To ensure the quality of the first initial saturated steam generated, the water temperature at the primary water inlet of the first steam generator 2 can be maintained at 248 + T1°C. To ensure the quality of the second initial saturated steam generated, the water temperature at the primary water inlet of the second steam generator 3 can be maintained at 234 + T2°C. Furthermore, to prevent the water temperature at the secondary water inlet of the heat exchanger 12 from being too low and thus affecting the operating stability of the nuclear reactor 11, the water temperature at the primary water outlet of the second steam generator 3 can be maintained at 208 + T3°C. The ranges of T1, T2, and T3 are -4 to +4°C, respectively. Specifically, the temperature of the circulating water can be achieved by controlling the power of the nuclear reactor 11. The power control method of the nuclear reactor 11 can refer to the existing technology and will not be described in detail here.

[0053] In some embodiments, the reheat unit 5 can be a gas-fired oil boiler, a molten salt heat exchanger, a gas turbine flue gas waste heat boiler, a thermal power plant boiler, an electric heater, or a gas heater.

[0054] In some embodiments, as shown in FIG1 , the make-up water treatment unit 6 includes a first sub-make-up water treatment unit 61 and a second sub-make-up water treatment unit 62. The steam inlet of the first sub-make-up water treatment unit 61 is connected to the secondary steam outlet of the first steam generator 2 or the secondary steam outlet of the second steam generator 3, and the make-up water outlet of the first sub-make-up water treatment unit 61 is connected to the secondary make-up water inlet of the first steam generator 2. The make-up water inlet of the first sub-make-up water treatment unit 61 is used to receive make-up water for heating and deoxygenating the make-up water using initial saturated steam (either the first initial saturated steam or the second initial saturated steam). The steam inlet of the second sub-make-up water treatment unit 62 is connected to the secondary steam outlet of the first steam generator 2 or the secondary steam outlet of the second steam generator 3, and the make-up water outlet of the second sub-make-up water treatment unit 62 is connected to the secondary make-up water inlet of the second steam generator 3. The make-up water inlet of the second sub-make-up water treatment unit 62 is used to receive make-up water for heating and deoxygenating the make-up water using initial saturated steam (either the first initial saturated steam or the second initial saturated steam).

[0055] In some embodiments, as shown in FIG1 , the first sub-water make-up treatment unit 61 may include a first deaerator 611, a first regulating valve 612, and a first booster pump 613. The make-up water inlet of the first deaerator 611 is used to receive make-up water, the steam inlet of the first deaerator 611 is connected to the secondary steam outlet of the first steam generator 2 or the secondary steam outlet of the second steam generator 3 via the first regulating valve 612, and the make-up water outlet of the first deaerator 611 is connected to the secondary make-up water inlet of the first steam generator 2 via the first booster pump 613.

[0056] In this embodiment, the first deaerator 611 can be an existing deaerator, which can use the first initial saturated steam to deoxygenate, pressurize and heat water; the first regulating valve 612 can be an existing electric regulating valve, which can control the steam flow input to the first deaerator 611 by adjusting the valve opening. It can be understood that the steam flow can be determined according to the current target pressure of steam production, that is, by adjusting the opening of the first regulating valve 612, the pressure of the deoxygenation steam from the first initial saturated steam can be controlled.

[0057] Furthermore, in order to ensure that the first steam generator 2 improves the efficiency of producing the first initial saturated steam, the temperature range of the feed water after heating by the first deaerator 611 can be controlled within 145~201°C. This can reduce the thermal energy required by the first steam generator 2 to convert the feed water into steam, that is, reduce the primary side thermal energy demand of the first steam generator 2, which helps to produce steam with a pressure greater than that of low-pressure superheated steam.

[0058] In some embodiments, as shown in FIG1 , the second sub-water make-up treatment unit 62 includes a second deaerator 621, a second regulating valve 622, and a second booster pump 623. The water make-up inlet of the second deaerator 621 is used to receive make-up water. The steam inlet of the second deaerator 621 is connected to the secondary steam outlet of the first steam generator 2 or the secondary steam outlet of the second steam generator 3 via the second regulating valve 622. The water make-up outlet of the second deaerator 621 is connected to the secondary water make-up inlet of the second steam generator 3 via the second booster pump 623.

[0059] In this embodiment, the second deaerator 621 can be an existing deaerator, which can use the second initial saturated steam to deoxygenate and heat water; the second regulating valve 622 can be an existing electric regulating valve, which can control the steam flow input to the second deaerator 621 by adjusting the valve opening, that is, by adjusting the opening of the second regulating valve 622, the pressure of the deoxygenation steam from the second initial saturated steam can be controlled.

[0060] Furthermore, in order to ensure that the second steam generator 3 improves the efficiency of producing the second initial saturated steam, the temperature range of the feed water after heating by the second deaerator 621 can be controlled within 135~155°C, so that the primary side return water temperature of the second steam generator 3 can be maintained.

[0061] In some embodiments, as shown in FIG2 , the water supply processing unit 6 further includes a fifth regulating valve 63 and a sixth regulating valve 64. The fifth regulating valve 63 is connected between the second boosting pump 623 and the secondary-side water supply inlet of the second steam generator 3. The connection node between the second boosting pump 623 and the fifth regulating valve 63 is also connected to the water supply inlet of the first deaerator 611 via the sixth regulating valve 64.

[0062] In this embodiment, the feed water heated and deoxygenated by the second deaerator 621 is used as feed water for the first deaerator 611. This is equivalent to secondary heating and deoxygenating the feed water for the first steam generator 2, which helps the first steam generator 2 produce higher-pressure first initial saturated steam. Furthermore, the opening of the fifth regulating valve 63 controls the feed water flow rate input to the second steam generator 3, while the sixth regulating valve 64 controls the feed water flow rate input to the first deaerator 611 (i.e., the first steam generator 2).

[0063] In some embodiments, as shown in FIG3 , the multi-pressure steam supply system for the low-temperature heating reactor further includes a high-pressure superheated steam pretreatment unit 7 . The make-up water inlet of the high-pressure superheated steam pretreatment unit 7 is connected to desalted water. The steam inlet of the high-pressure superheated steam pretreatment unit 7 is connected to the secondary side of the first steam generator 2 and the secondary side of the second steam generator 3 . The desalted water is heated and deoxygenated using the first initial saturated steam and the second initial saturated steam before being transferred to the reheat unit 5 . Accordingly, the reheat unit 5 reheats, vaporizes, and superheats the deoxygenated desalted water to produce high-pressure superheated steam.

[0064] In this embodiment, the desalted water is subjected to secondary heating and deoxygenation by the first initial saturated steam and the second initial saturated steam, respectively, thereby greatly increasing the temperature and pressure of the desalted water and reducing the oxygen content of the desalted water. Subsequently, the high-temperature and high-pressure desalted water is reheated, vaporized, and superheated in the reheat unit 5 to obtain high-pressure superheated steam.

[0065] Optionally, the pressure of the high-pressure superheated steam may be in the range of 3.5 to 11 MPa. Further, the pressure of the high-pressure superheated steam is preferably 9.8 MPa. In this way, the superheat temperature of the high-pressure superheated steam can reach 510°C.

[0066] In order to ensure the quality of high-pressure superheated steam, desalted water with a temperature range of 20~104℃ can be input as raw material into the water replenishment inlet of the high-pressure superheated steam pretreatment unit 7. The higher the temperature, the more conducive it is to generating high-pressure superheated steam with a higher gas pressure.

[0067] In some embodiments, as shown in FIG3 , the high-pressure superheated steam pretreatment unit 7 includes a third deaerator 71, a third regulating valve 72, a third boosting pump 73, a fourth deaerator 74, and a fourth regulating valve 75. The steam inlet of the third deaerator 71 is connected to the secondary steam outlet of the second steam generator 3 via the third regulating valve 72, the make-up water inlet of the third deaerator 71 is connected to the desalted water, the make-up water outlet of the third deaerator 71 is connected to the make-up water inlet of the fourth deaerator 74 via the third boosting pump 73, the make-up water outlet of the fourth deaerator 74 is connected to the reheat unit 5, and the steam inlet of the fourth deaerator 74 is connected to the secondary steam outlet of the first steam generator 2 via the fourth regulating valve 75.

[0068] In this embodiment, the desalted water is first heated and deoxygenated using the second initial saturated steam as a heat source in the third deaerator 71, bringing the desalted water temperature to approximately 195°C. Next, the desalted water is heated and deoxygenated using the first initial saturated steam as a heat source in the fourth deaerator 74, bringing the desalted water temperature to approximately 229°C. Finally, the desalted water, after the second heating and deoxygenation, enters the reheat unit 5 for heating and vaporization, thereby producing high-pressure superheated steam. The third booster pump 73 provides power for delivering the desalted water to the reheat unit 5, while the third and fourth regulating valves 72 and 75 regulate the flow rates of the first and second initial saturated steam entering the respective deaerators, respectively, thereby controlling the temperature of the desalted water. Specifically, by adjusting the openings of the third and fourth regulating valves 72 and 75, the pressure and temperature of the high-pressure superheated steam can be controlled.

[0069] Because the temperature and pressure of the desalted water are relatively high, to ensure that the desalted water can smoothly enter the reheat unit 5 after being heated and deoxygenated by the third deaerator 71 and the fourth deaerator 74, it is necessary to provide the desalted water with stable and sufficient power. Therefore, in some embodiments, as shown in FIG3 , the high-pressure superheated steam pretreatment unit 7 further includes a fourth booster pump 76 connected between the make-up water outlet of the fourth deaerator 74 and the reheat unit 5. In this embodiment, the fourth booster pump 76 can bring the pressure of the desalted water to approximately 11.7 MPa.a.

[0070] In some embodiments, as shown in FIG3 , the pipeline connecting the first deaerator 611 and the second deaerator 621 to the make-up water equipment passes through the reheat unit 5, so that the reheat unit 5 heats the make-up water input to the first deaerator 611 and the second deaerator 621. In this embodiment, by pre-deoxygenating and heating the make-up water to the first deaerator 611 and the second deaerator 621, the heat energy required by the first and second steam generators to vaporize the make-up water can be reduced, thereby improving water quality and producing higher-pressure steam. Furthermore, the heating function of the reheat unit 5 is fully utilized, thereby conserving resources.

[0071] Furthermore, in the embodiment shown in FIG2 , the feed water for the first and second steam generators originates from the same pipeline, and the first steam generator is required to produce first initial saturated steam at a higher pressure and temperature than the second initial saturated steam. To ensure that the feed water pressure of the first steam generator meets this requirement, as shown in FIG3 , the low-temperature heating reactor multi-pressure steam supply system further includes a fifth booster pump 8. The outlet of the fifth booster pump 8 is connected to the feed water inlet of the first deaerator 611, and the inlet of the fifth booster pump 8 is connected to the feed water inlet of the second deaerator 621 on one side and to the feed water equipment via a pipeline passing through the reheat unit 5 on the other side. In this embodiment, the function of the fifth booster pump 8 is to increase the feed water pressure input to the first deaerator 611, so that the first steam generator 2 can more efficiently generate the first initial saturated steam.

[0072] It should be noted that the steam required for the operation of the first deaerator 611 and the second deaerator 621 can actually be either the first or the second initial saturated steam as a heat source. In addition, although the second initial saturated steam as a heat source for the operation of the first deaerator consumes some steam, it can increase the medium-pressure steam production.

[0073] In some embodiments, as shown in FIG4 , the water replenishment processing unit may further include a fifth deaerator 631, a seventh regulating valve 632, and a sixth booster pump 633. The water replenishment inlet of the fifth deaerator 631 is used to receive replenishment water, the steam inlet of the fifth deaerator 631 is connected to the secondary steam outlet of the first steam generator 2 via the seventh regulating valve 632, the water replenishment outlet of the fifth deaerator 631 is connected to one end of a sixth booster pump 633, and the other end of the sixth booster pump 633 is connected to the secondary water replenishment inlet of the first steam generator 2 and the secondary water replenishment inlet of the second steam generator 3.

[0074] In this embodiment, the heating and deoxygenation of the feed water for the first steam generator 2 and the second steam generator 3 are achieved by sharing the fifth deaerator 631. Although the flow rate of the consumed second initial saturated steam is large, this helps to save the construction cost of the system. This embodiment is conducive to increasing the output of medium-pressure superheated steam.

[0075] It should be noted that, in the present invention, the opening control of the first to seventh regulating valves can be achieved by existing technologies, which will not be described in detail here.

[0076] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. Reference can be made to the common and similar parts between the various embodiments. For the devices disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the description is relatively simple, and the relevant parts can be referred to the method description.

[0077] It is understandable that the above embodiments only express the preferred implementation modes of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the patent scope of the present invention. It should be pointed out that for ordinary technicians in this field, without departing from the concept of the present invention, the above technical features can be freely combined, and several deformations and improvements can be made, all of which fall within the scope of protection of the present invention. Therefore, all equivalent changes and modifications made to the scope of the claims of the present invention should fall within the scope of coverage of the claims of the present invention.

Claims

1. A multi-pressure steam supply system for a low-temperature heating reactor, characterized in that: It includes a low-temperature heating reactor, a first steam generator, a second steam generator, an intermediate loop, a reheat unit and a water supply treatment unit; The low-temperature heating reactor, the primary side of the first steam generator, and the primary side of the second steam generator are respectively arranged on the intermediate loop, and the secondary sides of the first steam generator and the second steam generator respectively produce first initial saturated steam and second initial saturated steam using the heat energy generated by the low-temperature heating reactor; The reheat unit is connected to the secondary side of the first steam generator and the secondary side of the second steam generator, and reheats the first and second initial saturated steam to produce medium-pressure superheated steam and low-pressure superheated steam; The make-up water processing unit is connected to the secondary sides of the first steam generator and the second steam generator to heat and deoxygenate the make-up water of the two steam generators using initial saturated steam.

2. The multi-pressure steam supply system for a low-temperature heating reactor according to claim 1, characterized in that: The water replenishment processing unit includes a first sub-water replenishment processing unit and a second sub-water replenishment processing unit; The first sub-water replenishment treatment unit has a steam inlet connected to the secondary side steam outlet of the first steam generator or the secondary side steam outlet of the second steam generator, and a replenishment water outlet connected to the secondary side replenishment water inlet of the first steam generator. The replenishment water inlet is used to receive replenishment water to heat and deoxygenate the replenishment water using initial saturated steam; The steam inlet of the second sub-make-up water treatment unit is connected to the secondary side steam outlet of the first steam generator or the secondary side steam outlet of the second steam generator, and the make-up water outlet is connected to the secondary side make-up water inlet of the second steam generator. The make-up water inlet is used to receive make-up water to heat and deoxygenate the make-up water using initial saturated steam.

3. The multi-pressure steam supply system for a low-temperature heating reactor according to claim 2, characterized in that: The first sub-water replenishment treatment unit includes a first deaerator, a first regulating valve and a first booster pump; The water supply inlet of the first deaerator is used to receive water supply, the steam inlet of the first deaerator is connected to the secondary steam outlet of the first steam generator or the secondary steam outlet of the second steam generator via the first regulating valve, and the water supply outlet of the first deaerator is connected to the secondary water supply inlet of the first steam generator via the first booster pump; The second sub-water replenishment treatment unit includes a second deaerator, a second regulating valve and a second booster pump; The water make-up inlet of the second deaerator is used to connect make-up water, the steam inlet of the second deaerator is connected to the secondary side steam outlet of the first steam generator or the secondary side steam outlet of the second steam generator through the second regulating valve, and the water make-up outlet of the second deaerator is connected to the secondary side make-up water inlet of the second steam generator through the second booster pump.

4. The multi-pressure steam supply system for a low-temperature heating reactor according to claim 3, characterized in that: The temperature range of the feed water heated by the first deaerator is 145-201° C.; and / or the temperature range of the feed water heated by the second deaerator is 135-155° C.

5. The multi-pressure steam supply system for a low-temperature heating reactor according to claim 3, characterized in that: The water replenishment processing unit further includes a fifth regulating valve and a sixth regulating valve; The fifth regulating valve is connected between the second boost pump and the secondary side water supply inlet of the second steam generator. The connection node between the second boost pump and the fifth regulating valve is also connected to the water supply inlet of the first deaerator through the sixth regulating valve.

6. The multi-pressure steam supply system for a low-temperature heating reactor according to claim 1, characterized in that: The low-temperature heating reactor includes a nuclear reactor, a heat exchanger and a circulation pump; The secondary side outlet of the heat exchanger is connected to the secondary side inlet of the heat exchanger via the primary side of the first steam generator, the primary side of the second steam generator and the circulation pump in sequence. The heat exchanger cooperates with the nuclear reactor to utilize the heat energy generated by the nuclear reactor to heat the circulating water in its secondary side.

7. The multi-pressure steam supply system for a low-temperature heating reactor according to claim 1, characterized in that: The gas pressure range of the low-pressure superheated steam is 0.8~1.8MPa.a; and / or the gas pressure range of the medium-pressure superheated steam is 2.2~3.2MPa.a.

8. The multi-pressure steam supply system for a low-temperature heating reactor according to claim 1, characterized in that: The first steam generator is disposed on an upstream pipeline of the intermediate circuit, and the second steam generator is disposed on a downstream pipeline of the first steam generator.

9. The multi-pressure steam supply system for a low-temperature heating reactor according to claim 8, characterized in that: The water temperature at the primary water inlet of the first steam generator is maintained at 248+T1°C; and / or the water temperature at the primary water inlet of the second steam generator is maintained at 234+T2°C, and the water temperature at the primary water outlet of the second steam generator is maintained at 208+T3°C; wherein the ranges of T1, T2 and T3 are respectively -4~+4°C.

10. The multi-pressure steam supply system for a low-temperature heating reactor according to claim 1, characterized in that: The water replenishment treatment unit includes a fifth deaerator, a seventh regulating valve and a sixth booster pump; The water make-up inlet of the fifth deaerator is used to connect make-up water, the steam inlet of the fifth deaerator is connected to the secondary side steam outlet of the first steam generator or the secondary side steam outlet of the second steam generator through the seventh regulating valve, the water make-up outlet of the fifth deaerator is connected to one end of the sixth booster pump, and the other end of the sixth booster pump is connected to the secondary side make-up water inlet of the first steam generator and the secondary side make-up water inlet of the second steam generator.

11. The multi-pressure steam supply system for a low-temperature heating reactor according to any one of claims 3 to 10, characterized in that: It also includes a high-pressure superheated steam pretreatment unit; The water supply inlet of the high-pressure superheated steam pretreatment unit is connected to the desalted water, and the steam inlet of the high-pressure superheated steam pretreatment unit is connected to the secondary side of the first steam generator and the secondary side of the second steam generator, so as to utilize the first initial saturated steam and the second initial saturated steam to heat and deoxygenate the desalted water and then transport it to the reheat unit; The reheat unit further reheats the desalted water after heating and deoxygenation to produce high-pressure superheated steam.

12. The multi-pressure steam supply system for a low-temperature heating reactor according to claim 11, characterized in that: The high-pressure superheated steam pretreatment unit includes a third deaerator, a third regulating valve, a third booster pump, a fourth deaerator and a fourth regulating valve; The steam inlet of the third deaerator is connected to the secondary side steam outlet of the second steam generator through the third regulating valve, the make-up water inlet of the third deaerator is connected to the desalted water, the make-up water outlet of the third deaerator is connected to the make-up water inlet of the fourth deaerator through the third booster pump, the make-up water outlet of the fourth deaerator is connected to the reheat unit, and the steam inlet of the fourth deaerator is connected to the secondary side steam outlet of the first steam generator through the fourth regulating valve.

13. The multi-pressure steam supply system for a low-temperature heating reactor according to claim 12, characterized in that: The high-pressure superheated steam pretreatment unit further includes a fourth booster pump connected between the make-up water outlet of the fourth deaerator and the reheat unit.

14. The multi-pressure steam supply system for a low-temperature heating reactor according to claim 11, characterized in that: The pressure range of the high-pressure superheated steam is 3.5~11MPa.a.

15. The multi-pressure steam supply system for a low-temperature heating reactor according to claim 11, characterized in that: The pipelines connecting the first deaerator and the second deaerator to the water supply equipment pass through the reheat unit, so that the reheat unit heats the water supply input to the first deaerator and the second deaerator.

16. The multi-pressure steam supply system for a low-temperature heating reactor according to claim 15, characterized in that: Also included is a fifth boost pump; The outlet of the fifth booster pump is connected to the water supply inlet of the first deaerator, and the inlet of the fifth booster pump is connected to the water supply inlet of the second deaerator on one side and is connected to the water supply equipment through a pipeline passing through the reheat unit on the other side.

17. The multi-pressure steam supply system for a low-temperature heating reactor according to claim 16, characterized in that: The reheat unit is a gas-fired oil boiler, a molten salt heat exchanger, a gas turbine flue gas waste heat boiler, a thermal power plant boiler, an electric heater or a gas heater.

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