Heating system and method for detecting thermal load of heating system

Abstract

The invention relates to the technical field of nuclear power, in particular to a heating system and a thermal load detection method of the heating system. The heating system comprises a circulation loop, a heat exchange loop and a detection loop, and the circulation loop is filled with a gaseous medium; the heat exchange loop comprises a heat exchanger, the heat exchanger is arranged on the downstream side of the circulation loop, the gaseous medium is configured to flow from the circulation loop to the heat exchange loop so that heat exchange of the gaseous medium can be achieved at the heat exchanger, and the gaseous medium is condensed into a liquid medium after heat exchange; the detection loop comprises a detection element, and the detection element is arranged on the downstream side of the heat exchanger and used for detecting the flow of the liquid medium. The detection method is used for detecting the heat load of the heating system. The detection method is accurate in detection of the thermal load of the heating system.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of nuclear power, in particular to a heating system and a heat load detection method of the heating system. BACKGROUND

[0002] Nuclear energy belongs to clean energy, has no flue gas emission, and can replace coal-fired cogeneration units to improve haze. It can adapt to the pressure of nuclear power unit peak shaving and load reduction caused by future possible supply-side adjustment of power grid, effectively increase the share of clean energy in future energy mix, and expand the competitiveness of nuclear power. Under this situation, the steam generated by the reactor of a large pressurized water reactor nuclear power unit is extracted to supply heat to the city while driving the generator to generate electricity, which is the dual needs of nuclear power generation enterprises and environmental protection.

[0003] Considering the extraction working condition of the steam turbine, in fact, the secondary circuit load becomes two parts of the steam turbine power generation load and the heating load. The power generation load can be directly measured from the generator power table, and the change of the heating load will affect the heat balance process of the secondary circuit. Therefore, accurate detection of the heating load of the secondary circuit is particularly important. SUMMARY

[0004] The main purpose of the present application is to provide a heating system and a heat load detection method of the heating system, which aims to solve the technical problem of inaccurate detection of the heating load of the secondary circuit.

[0005] To achieve the above-mentioned purpose, the present application provides a heating system, comprising:

[0006] A circulating loop, wherein the circulating loop is filled with gaseous medium;

[0007] A heat exchange loop, wherein the heat exchange loop comprises a heat exchanger, the heat exchanger is arranged on the downstream side of the circulating loop, and the heat exchanger is configured to receive the gaseous medium in the circulating loop and enable the gaseous medium to realize heat exchange at the heat exchanger, and the gaseous medium is condensed into liquid medium after heat exchange;

[0008] A detection loop, wherein the detection loop comprises a detection element, the detection element is arranged on the downstream side of the heat exchanger, and the detection element is used to detect the flow of the liquid medium.

[0009] In some embodiments, the detection loop comprises a booster element, the booster element is arranged on the downstream side of the heat exchanger and on the upstream side of the detection element, and the booster element is used to boost the liquid medium.

[0010] In some embodiments, the detection loop comprises a connecting pipe through which the detection element is connected to the downstream side of the pressure boosting element, the detection element comprises a hole plate provided with flow holes through which the liquid medium flows;

[0011] In some embodiments, the ratio B of the hole diameter of the flow holes to the pipe diameter of the connecting pipe satisfies: 0.2 < B < 0.6.

[0012] In some embodiments, the detection loop comprises a rectifier provided on the downstream side of the pressure boosting element and on the upstream side of the detection element.

[0013] In some embodiments, the circulation loop comprises a condenser and a heater group provided on the downstream side of the condenser, the condenser is used to condense the gaseous medium into the liquid medium, the heater group is used to evaporate the liquid medium into the gaseous medium and to warm the gaseous medium to a target temperature;

[0014] The heater group comprises a first heater provided on one side close to the condenser, and the detection loop has a liquid outlet provided on the downstream side of the first heater.

[0015] In some embodiments, the heater group comprises a second heater provided on the downstream side of the first heater, and the liquid outlet is provided on the downstream side of the first heater and on the upstream side of the second heater.

[0016] In some embodiments, the first heater is used to heat the liquid medium to a first heating temperature, and the second heater is used to heat the liquid medium to a second heating temperature, the second heating temperature being higher than the first heating temperature.

[0017] In some embodiments, the first heating temperature T1 satisfies: 80℃ ≤ T1 ≤ 90℃, and the second heating temperature T2 satisfies: 220℃ ≤ T2 ≤ 230℃.

[0018] In some embodiments, the heater group comprises a steam generator provided on the downstream side of the second heater.

[0019] In some embodiments, the steam generator is used to evaporate the liquid medium into the gaseous medium.

[0020] In some embodiments, the heater group comprises a steam generator provided on the downstream side of the second heater, and the circulation loop comprises a deaerator provided on the downstream side of the liquid outlet and on the upstream side of the steam generator.

[0021] In some embodiments, the heater group comprises a steam generator disposed at a downstream side of the second heater; the circulation loop comprises a power generator and a plurality of pressure cylinders disposed at a downstream side of the steam generator, the plurality of pressure cylinders configured to absorb the gaseous medium vaporized by the steam generator and convert thermal energy or pressure energy of the gaseous medium into mechanical energy to drive the power generator to work.

[0022] In some embodiments, the plurality of pressure cylinders comprises at least a high-pressure cylinder, a medium-pressure cylinder disposed at a downstream side of the high-pressure cylinder, and a low-pressure cylinder disposed at a downstream side of the medium-pressure cylinder, the heat exchange loop having an intake end in communication with the heat exchanger;

[0023] wherein the intake end is disposed at a downstream side of the medium-pressure cylinder and at an upstream side of the low-pressure cylinder, the gaseous medium in the medium-pressure cylinder flowing at least partially to the heat exchanger through the intake end.

[0024] In some embodiments, the heat exchange loop comprises an air extraction valve group disposed at a downstream side of the intake end and at an upstream side of the heat exchanger, the air extraction valve group configured to extract the gaseous medium at the intake end to the heat exchanger.

[0025] In some embodiments, the low-pressure cylinder is disposed at an upstream side of the condenser, the gaseous medium in the low-pressure cylinder flowing to the condenser to cause the condenser to condense the gaseous medium into the liquid medium.

[0026] In some embodiments, the heating system comprises a one-loop and a three-loop, the one-loop connected to the steam generator and configured to transfer heat to the steam generator, the three-loop connected to the condenser and configured to absorb heat generated when the gaseous medium in the condenser is condensed into the liquid medium.

[0027] In some embodiments, the heat exchange loop comprises a first branch and a second branch, the heat exchanger disposed between the first branch and the second branch, the first branch and the second branch both configured to transport a flow medium;

[0028] wherein the flow medium in the first branch flows to the second branch after passing through the heat exchanger, such that the temperature of the flow medium in the second branch is higher than the temperature of the flow medium in the first branch.

[0029] Correspondingly, the application further provides a heat load detection method of a heating system, which is used for detecting the heat load by using the heating system in any of the above embodiments, and comprises the following steps of:

[0030] The gaseous medium in the circulation loop flows into the heat exchange loop, and after heat exchange is completed at the heat exchanger in the heat exchange loop, the gaseous medium is condensed into liquid medium;

[0031] The liquid medium in the heat exchange loop flows into the detection loop, and the detection element detects the flow of the liquid medium.

[0032] In some embodiments, the liquid medium is pressurized before flowing into the detection element.

[0033] In some embodiments, detection data is generated according to the flow detection result of the detection element, and the actual heat load of the heating system is obtained by comparing the detection data with a preset curve between the heat extraction amount and the heat load.

[0034] Compared with the prior art, the application has the following beneficial effects:

[0035] In the technical solution of the application, taking the temperature rising process of the heat exchanger in the heat exchange loop as an example, the circulation loop is used to provide gaseous medium with a higher temperature, and the gaseous medium in the circulation loop can flow to the heat exchanger in the heat exchange loop. The gaseous medium exchanges heat at the heat exchanger, so that the temperature of the heat exchanger is raised, thereby ensuring that the heat exchanger can heat the flowing medium in the heat exchange loop, so that the heat exchange loop can heat other systems. After a large amount of heat exchange at the heat exchanger, the gaseous medium is condensed into liquid medium, and the liquid medium flows to the detection loop and then to the detection element along the detection loop, and the flow of the liquid medium is detected at the detection element. Since the liquid medium is formed by the condensation of the gaseous medium at the heat exchanger, the flow change of the liquid medium represents the flow change of the gaseous medium used for heating, that is, the flow change value of the liquid medium is completely equivalent to the flow change value of the gaseous medium used for heating. According to the relationship curve between the heat extraction amount and the heat load under different loads, and based on the flow change value of the gaseous medium, the heat load of the heating system can be directly obtained.

[0036] Compared with the detection mode of detecting the heat load by using the traditional temperature measuring point, the detection mode provided by the application can effectively improve the detection accuracy and reduce the detection hysteresis. On the one hand, the physical properties (such as density, viscosity, etc.) of the liquid medium are more stable than those of the gaseous medium, and are less affected by temperature and pressure fluctuations. Therefore, the detection result of the liquid medium flow can more truly, directly and stably reflect the actual total amount of the gaseous medium for heating at the heat exchanger, thereby greatly improving the detection accuracy of the heat load of the heating system. On the other hand, the detection element can detect the flow of the liquid medium flowing therethrough in real time, so that the detection of the liquid medium by the detection element has real-time performance, avoiding the problem of detection hysteresis existing in temperature detection.

[0037] The detection method provided by the application has few measuring points and high measurement accuracy, and can provide accurate data for real-time metering of the external heat supply of the nuclear power plant. By using the detection method provided by the application, on the one hand, the accuracy and real-time performance of the nuclear energy heating heat load identification are improved; on the other hand, the economy of the nuclear energy heating is improved. BRIEF DESCRIPTION OF DRAWINGS

[0038] In order to more clearly illustrate the technical solutions in the embodiments of the application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or the prior art description. Obviously, the drawings in the following description only constitute some embodiments of the application, and for those skilled in the art, other drawings can also be obtained from the structures shown in the drawings without creative labor.

[0039] Figure 1 The overall structure schematic diagram of the heating system provided by an embodiment of the application is shown in the figure.

[0040] Figure 2 The curve diagram between the preset heat supply extraction steam amount and the heat load in the heating system provided by an embodiment of the application is shown in the figure.

[0041] Figure 3 The unit power schematic diagram of the heating system provided by an embodiment of the application, in which the liquid outlet end is directly connected to the condenser, is shown in the figure.

[0042] Figure 4 The unit power schematic diagram of the heating system provided by an embodiment of the application, in which the liquid outlet end is connected to the downstream side of the first heater, is shown in the figure.

[0043] Figure 5 The flowchart of the heat load detection method of the heating system provided by an embodiment of the application is shown in the figure.

[0044] BRIEF DESCRIPTION OF DRAWINGS

[0045] 10. Heating system;

[0046] 100. Circulation loop;

[0047] 110. Condenser; 120. Heater group; 130. Deaerator; 140. High-pressure cylinder; 150. Medium-pressure cylinder; 160. Low-pressure cylinder; 170. Generator;

[0048] 121. First heater; 122. Second heater; 123. Steam generator;

[0049] 200. Heat exchange loop;

[0050] 210. Heat exchanger; 220. Suction valve group; 230. Inlet end; 240. First branch; 250. Second branch;

[0051] 300. Detection loop;

[0052] 310. Detection element; 320. Voltage boosting element; 330. Rectifier; 340. Outlet end.

[0053] The implementation, functional features and advantages of the present application will be further described with reference to the accompanying drawings. DETAILED DESCRIPTION

[0054] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all the other embodiments obtained by those skilled in the art without any creative work under the premise that the specific working conditions are changed, belong to the scope of protection of the present application.

[0055] It should be noted that if the embodiments of the present application involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative position relationship, movement condition, etc. between the components in a certain specific posture, and if the specific posture is changed, the directional indications will also change accordingly.

[0056] In addition, if the description of "first", "second" and the like is involved in the embodiments of the present application, the description of "first", "second" and the like is only for the purpose of description, and cannot be understood as indicating or implying the relative importance of the indicated technical features or implicitly indicating the number of the indicated technical features. Therefore, the features limited by "first", "second" can be explicitly or implicitly included at least one of the features. In addition, if "and / or", "and / or" or "and / or" appears throughout the text, it means that the three parallel schemes include "A and / or B", including A scheme, or B scheme, or A and B scheme. In addition, the technical solutions of each embodiment can be combined with each other, but it must be based on the realization of ordinary skilled in the art, when the combination of technical solutions appears contradictory or unachievable, it should be considered that the combination of technical solutions does not exist, nor within the scope of protection required by the present application.

[0057] Nuclear energy belongs to clean energy, no smoke emission, instead of coal-fired cogeneration unit, can improve haze. Adapt to the future possible supply side adjustment of power grid brings nuclear power unit peak regulation, reduce load pressure, effectively improve the share of clean energy in future energy, expand the competitiveness of nuclear power. Under this situation, the large pressurized water reactor nuclear power unit reactor generated by the second loop steam enters the steam turbine to drive the generator to generate electricity at the same time, and a part is extracted to supply heat to the municipal government, which is the dual needs of nuclear power generation enterprises and environmental protection.

[0058] Considering the steam extraction working condition of the steam turbine, in fact, the load of the second loop becomes two parts of the power generation load of the steam turbine and the heating load. The power generation load can be directly measured from the generator power table, and the change of the heating load will affect the heat balance process of the second loop. Therefore, the accurate detection of the heating load of the second loop is particularly important.

[0059] For example, the current method for identifying the heating load of nuclear heating is to measure the temperature difference and mass flow rate of the circulating water at the inlet and outlet of the hot water circulating heater in real time, and to calculate the heating load by multiplying the specific heat capacity of hot water, mass flow rate and temperature rise. However, due to the large amount of circulating water on the hot water side, the measured value of the temperature measuring point will be delayed, resulting in a delay in the calculated heating load, which will have a certain impact on the real-time aspect of the matching control of the nuclear heating reactor.

[0060] Therefore, in order to solve the technical problem of inaccurate detection of the heating load of the second loop and detection lag, with reference to Figure 1An embodiment of the present application provides a heating system 10, which comprises a circulation loop 100, a heat exchange loop 200 and a detection loop 300. The circulation loop 100 is filled with gaseous medium, for example, the gaseous medium can be water vapor. The heat exchange loop 200 comprises a heat exchanger 210, which is arranged at a downstream side of the circulation loop 100, and the gaseous medium is configured to flow from the circulation loop 100 to the heat exchange loop 200, so that the gaseous medium realizes heat exchange at the heat exchanger 210, and the gaseous medium is condensed into liquid medium after the heat exchange. For example, the heat exchange loop 200 can be heated by using the heat exchanger 210, at this time, the gaseous medium in the circulation loop 100 flowing to the heat exchange loop 200 has a higher temperature, so as to ensure that the heat exchanger 210 has a higher heat exchange efficiency. The detection loop 300 comprises a detection element 310, for example, the detection element 310 can be a (liquid) flow measuring element, and the detection element 310 is arranged at a downstream side of the heat exchanger 210, and is used for detecting the flow of the liquid medium.

[0061] Specifically, in the embodiment, taking the heating process of the heat exchange loop 200 at the heat exchanger 210 as an example, the circulation loop 100 is used to provide gaseous medium with a higher temperature, and the gaseous medium in the circulation loop 100 can flow to the heat exchanger 210 of the heat exchange loop 200, the gaseous medium realizes heat exchange at the heat exchanger 210, so that the temperature of the heat exchanger 210 is increased, thereby ensuring that the heat exchanger 210 can heat the flowing medium in the heat exchange loop 200, so that the heat exchange loop 200 can heat other systems. After the gaseous medium realizes a large amount of heat exchange at the heat exchanger 210, the gaseous medium can be condensed into liquid medium, the liquid medium flows to the detection loop 300, and then flows to the detection element 310 along the detection loop 300, and the flow of the liquid medium is detected at the detection element 310. Since the liquid medium is formed by the condensation of the gaseous medium at the heat exchanger 210, the flow change of the liquid medium represents the flow change of the gaseous medium used for heating, that is, the flow change value of the liquid medium is completely equivalent to the flow change value of the gaseous medium used for heating. According to the relationship curve between the heating steam extraction amount and the heat load under different loads, and based on the flow change value of the gaseous medium, the heat load of the heating system 10 can be directly obtained.

[0062] Compared with the detection method of detecting the heat load by using the traditional temperature measuring point, the detection method provided by the embodiment can effectively improve the detection accuracy and reduce the detection hysteresis. On the one hand, the physical properties (such as density, viscosity, etc.) of the liquid medium are more stable than those of the gaseous medium, and are less affected by temperature and pressure fluctuations. Therefore, the detection result of the liquid medium flow can more truly, directly and stably reflect the actual total amount of the gaseous medium for heating at the heat exchanger 210, thereby greatly improving the detection accuracy of the heat load of the heating system 10. On the other hand, the detection element 310 can detect the flow of the liquid medium flowing therethrough in real time, so that the detection of the liquid medium by the detection element 310 has real-time performance, avoiding the problem of detection hysteresis existing in temperature detection.

[0063] It should be noted that the circulation loop 100, the heat exchange loop 200 and the detection loop 300 can be communicated through the connecting pipeline to ensure the sealing of the heating system 10.

[0064] In some embodiments, referring to Figure 1 The detection loop 300 includes a pressure boosting element 320, for example, the pressure boosting element 320 can be a water pump. The pressure boosting element 320 is arranged on the downstream side of the heat exchanger 210 and on the upstream side of the detection element 310, and is used to boost the liquid medium. The liquid medium condensed at the heat exchanger 210 first flows to the pressure boosting element 320, so that the liquid medium is boosted at the pressure boosting element 320 and then flows to the detection element 310 for flow detection.

[0065] Specifically, in the embodiment, the condensed liquid medium at the outlet of the heat exchanger 210 can be in a saturated state or close to a saturated state, and local resistance loss or small amplitude fluctuation of temperature in the detection loop 300 can easily cause flashing (local vaporization) in the low pressure area, forming gas-liquid two-phase flow, which can seriously interfere with the detection accuracy of the liquid medium flow by the detection element 310. The pressure boosting element 320 boosts the liquid medium, which can ensure that the liquid medium has sufficient subcooling pressure at the detection element 310, so that the liquid medium becomes single-phase subcooling water without steam after being boosted, thereby effectively inhibiting the occurrence of flashing and cavitation, ensuring that the liquid medium is stable single-phase liquid, greatly eliminating the measurement error caused by phase change interference, and further improving the detection accuracy of the liquid medium flow by the detection element 310.

[0066] In some embodiments, referring to Figure 1The detection circuit 300 comprises a connecting pipe through which the detection element 310 is connected to the downstream side of the pressure boosting element 320, and the detection element 310 comprises a perforated plate provided with flow holes through which the liquid medium flows. The ratio B of the hole diameter of the flow holes to the pipe diameter of the connecting pipe satisfies 0.2 < B < 0.6. For example, B can be 0.3, 0.4, 0.45, 0.5, 0.55, etc.

[0067] Specifically, in the embodiment, the value of B is set in the above range, which can ensure the detection accuracy of the detection element 310 to the flow of the liquid medium and improve the detection efficiency of the detection element 310 to the liquid medium. On the one hand, if the value of B is too small (for example, B is 0.05 or 0.1), the hole diameter of the flow holes will be too small, which will cause excessive throttling of the liquid medium flowing through the flow holes, and if the hole diameter of the flow holes is too small, the flow velocity of the liquid medium flowing through the perforated plate will be increased, which will aggravate the erosion and wear of the edge of the perforated plate. On the other hand, if the value of B is too large (for example, B is 0.7 or 1.0), the hole diameter of the flow holes will be too large, which will cause the differential pressure signal of the liquid medium flowing through the flow holes to be too small, which is not conducive to improving the detection sensitivity and accuracy of the detection element 310 to the flow of the liquid medium.

[0068] In some embodiments, referring to Figure 1 The detection circuit 300 comprises a rectifier 330 arranged on the downstream side of the pressure boosting element 320 and on the upstream side of the detection element 310. The liquid medium in the detection circuit 300 flows through the pressure boosting element 320, the rectifier 330 and the detection element 310 in sequence.

[0069] Specifically, in the embodiment, after flowing through the pressure boosting element 320, the liquid medium can have problems such as turbulent flow, vortex flow or uneven flow velocity distribution, which will cause the flow field of the liquid medium to be disordered. The rectifier 330 can effectively homogenize the flow velocity distribution of the liquid medium, eliminate the vortex of the liquid medium and stabilize the flow state of the liquid medium, so that the liquid medium forms laminar flow or stable turbulent flow before entering the detection element 310, thereby ensuring the detection accuracy of the detection element 310 to the flow of the liquid medium.

[0070] In some embodiments, referring to Figure 1The circulating loop 100 comprises a condenser 110 and a heater group 120, the heater group 120 is arranged at the downstream side of the condenser 110, the condenser 110 is used for condensing the gaseous medium into liquid medium, and the heater group 120 is used for evaporating the liquid medium into gaseous medium and warming the gaseous medium to a target temperature. For example, after a complete cycle of heat exchange, the remaining gaseous medium in the circulating loop 100 can be first condensed into liquid medium by the condenser 110, and then the liquid medium in the circulating loop 100 is evaporated into gaseous medium by the heater group 120 to increase the temperature and pressure of the gaseous medium, so as to ensure the normal operation of the next cycle of heat exchange.

[0071] With reference to Figure 1 The heater group 120 comprises a first heater 121 arranged at one side close to the condenser 110. After the condenser 110 condenses the gaseous medium in the circulating loop 100 into liquid medium, the first heater 121 first heats and warms the liquid medium to a first heating temperature. The first heater 121 can preheat the liquid medium, so as to facilitate the subsequent step-by-step heating and warming of the liquid medium, thereby facilitating the improvement of the heating efficiency of the liquid medium and saving the heating cost of the liquid medium.

[0072] With reference to Figure 1 The detection loop 300 has a liquid outlet 340 arranged at the downstream side of the first heater 121. After the flow detection of the liquid medium in the detection loop 300 by the detection element 310 is completed, the liquid medium in the detection loop 300 will flow back to the circulating loop 100 again. Since the liquid medium in the detection loop 300 is formed after being condensed by heat exchange at the heat exchanger 210, the liquid medium in the detection loop 300 has a certain temperature, that is, the liquid medium in the detection loop 300 does not need to be heated in the first heater 121 again, but can be directly combined with the liquid medium in the circulating loop 100 after being heated by the first heater 121. Moreover, the liquid medium in the detection loop 300 is pre-pressurized, so the liquid medium in the detection loop 300 has a high liquid pressure and can directly flow back to the downstream side of the first heater 121 in the circulating loop 100.

[0073] For example, with reference to Figure 3 and Figure 4 When the heating load is 300 MW, compared with directly connecting the liquid outlet 340 to the condenser 110, connecting the liquid outlet 340 to the downstream side of the first heater 121 can increase the unit power by 1868 KW. According to the heating for 5 months, it is equivalent to an additional annual income of about 3 million yuan.

[0074] Specifically, in the embodiment, the above structure is adopted, so that the liquid medium and the gaseous medium in the circulation loop 100 can be efficiently converted and recycled, and the gaseous medium in the circulation loop 100 can have a high temperature and a high pressure after being heated, so as to improve the heat exchange efficiency of the gaseous medium in the heat exchange loop 200. The liquid medium in the detection loop 300 flows to the circulation loop 100 in the above manner, which is beneficial to saving the heating energy and reducing the heating cost.

[0075] In some embodiments, with reference to Figure 1 The heater group 120 includes a second heater 122, which is arranged on the downstream side of the first heater 121, and the liquid outlet 340 is arranged on the downstream side of the first heater 121 and on the upstream side of the second heater 122. On the one hand, the second heater 122 is used to heat the liquid medium in the circulation loop 100 after being heated by the first heater 121; on the other hand, the second heater 122 is used to heat the liquid medium flowing from the detection loop 300 to the circulation loop 100. The first heater 121 is used to heat the liquid medium to a first heating temperature, and the second heater 122 is used to heat the liquid medium to a second heating temperature, which is higher than the first heating temperature. For example, the first heating temperature T1 satisfies 80℃≤T1≤90℃, and the second heating temperature T2 satisfies 220℃≤T2≤230℃. For example, T1 can be 80℃, 82℃, 85℃, 87℃, 90℃, etc. T2 can be 220℃, 222℃, 225℃, 228℃, 230℃, etc. It should be noted that since the first heater 121 and the second heater 122 are both closed containers, and the pressure in the first heater 121 and the second heater 122 is greater than the standard atmospheric pressure, even if the temperature in the first heater 121 and the second heater 122 reaches two or three hundred degrees Celsius, the first heater 121 and the second heater 122 will still be in a gas-liquid coexistence state (i.e., the first heater 121 and the second heater 122 can include both gaseous medium and liquid medium).

[0076] Specifically, in the embodiment, the liquid medium in the circulation loop 100 can be gradually heated after being heated by the first heater 121 and the second heater 122. By using the mode of gradual heating, on the one hand, the heat loss caused by single-stage large temperature difference heating can be effectively reduced, and the heat energy utilization efficiency of the first heater 121 and the second heater 122 can be improved. By reasonably distributing the heat load of the first heater 121 and the second heater 122, the heating power of the first heater 121 and the second heater 122 can be flexibly adjusted according to the actual heating demand, so as to avoid energy waste. On the other hand, the thermal stress problem caused by the sudden change of the temperature of the liquid medium can be effectively avoided, the thermal shock of the liquid medium caused by the sudden temperature rise can be prevented, and the heating stability of the liquid medium can be improved.

[0077] In some embodiments, with reference to Figure 1 The heater group 120 includes a steam generator 123, which is arranged on the downstream side of the second heater 122. The steam generator 123 is used to evaporate the liquid medium into gaseous medium. After being gradually heated by the first heater 121 and the second heater 122, the liquid medium in the circulation loop 100 is completely converted into gaseous medium in the steam generator 123.

[0078] Specifically, in the embodiment, the liquid medium can be completely converted into gaseous medium by the steam generator 123 before entering the heat exchange loop 200. The gaseous medium is used to realize heat exchange at the heat exchanger 210 of the heat exchange loop 200. On the one hand, since the gaseous medium has a higher temperature than the liquid medium, the heat exchange efficiency at the heat exchanger 210 can be improved, and the heat exchange time at the heat exchanger 210 can be shortened. On the other hand, by detecting the flow of the liquid medium condensed from the gaseous medium at the heat exchanger 210, the heating heat load in the secondary loop can be accurately obtained.

[0079] In some embodiments, with reference to Figure 1 The heater group 120 includes a steam generator 123, which is arranged on the downstream side of the second heater 122. The circulation loop 100 includes a deaerator 130, which is arranged on the downstream side of the liquid outlet 340 and on the upstream side of the steam generator 123. For example, the deaerator 130 can be arranged between the liquid outlet 340 and the second heater 122. Alternatively, the deaerator 130 can be arranged between the second heater 122 and the steam generator 123.

[0080] Specifically, in the embodiment, the oxygen in the liquid medium is removed by the deaerator 130 before the liquid medium enters the steam generator 123, so that the oxidation reaction in the steam generator 123 can be effectively avoided when the evaporation reaction of the liquid medium in the steam generator 123 occurs, thereby avoiding the corrosion of the steam generator 123 and prolonging the service life of the steam generator 123.

[0081] In some embodiments, referring to Figure 1 The heater group 120 includes a steam generator 123 arranged at the downstream side of the second heater 122, and the circulating loop 100 includes a generator 170 and a plurality of pressure cylinders arranged at the downstream side of the steam generator 123, which are configured to absorb the gaseous medium evaporated by the steam generator 123 and convert the thermal energy or pressure energy of the gaseous medium into mechanical energy to drive the generator 170 to work.

[0082] Specifically, in the embodiment, when the heat exchange loop 200 is heated by the gaseous medium, the thermal energy and pressure energy of the gaseous medium itself can also be used to drive the pressure cylinders to work, so that the pressure cylinders generate mechanical energy, and then the mechanical energy generated by the pressure cylinders is used to drive the generator 170 to work, so that the generator 170 supplies power to the system. With the above structure, not only can the heating of the citizens be realized, but also the power generation of the system can be realized, the nuclear energy and nuclear heat are effectively utilized, the waste of clean energy is avoided, and the concept of environmental protection is met.

[0083] In some embodiments, referring to Figure 1 The plurality of pressure cylinders at least include a high-pressure cylinder 140, a medium-pressure cylinder 150, and a low-pressure cylinder 160, the medium-pressure cylinder 150 is arranged at the downstream side of the high-pressure cylinder 140, and the low-pressure cylinder 160 is arranged at the downstream side of the medium-pressure cylinder 150, and the heat exchange loop 200 has an air inlet end 230 in communication with the heat exchanger 210. The air inlet end 230 is arranged at the downstream side of the medium-pressure cylinder 150 and at the upstream side of the low-pressure cylinder 160, and the gaseous medium in the medium-pressure cylinder 150 at least partially flows to the heat exchanger 210 through the air inlet end 230. In addition, the gaseous medium in the medium-pressure cylinder 150 also flows to the low-pressure cylinder 160 to drive the low-pressure cylinder 160 to work.

[0084] Specifically, in the embodiment, the gaseous medium will consume heat and pressure when passing through each cylinder, so the plurality of cylinders are high-pressure cylinder 140, medium-pressure cylinder 150 and low-pressure cylinder 160 along the flow direction of the gaseous medium. The intake end 230 of the heat exchange circuit 200 is arranged between the medium-pressure cylinder 150 and the low-pressure cylinder 160. On the one hand, compared with arranging the intake end 230 of the heat exchange circuit 200 between the high-pressure cylinder 140 and the medium-pressure cylinder 150, the gaseous medium with higher heat energy and pressure energy can work on the generator 170 more, improving the power generation efficiency of the generator 170, and avoiding the waste of heat of the gaseous medium. (It can be understood that in order to ensure the comfort of heating, the temperature of the gaseous medium used for heat exchange heating should not be too high, otherwise it is easy to cause overheating of heating); on the other hand, compared with arranging the intake end 230 of the heat exchange circuit 200 on the downstream side of the low-pressure cylinder 160, the heat exchange efficiency of the gaseous medium at the heat exchanger 210 can be ensured, and the heat exchange effect at the heat exchanger 210 is poor, which causes the temperature of the gaseous medium after heat exchange to meet the heating demand (It can be understood that in order to ensure the comfort of heating, the temperature of the gaseous medium used for heat exchange heating should not be too low, otherwise it is easy to cause insufficient heating temperature).

[0085] In some embodiments, with reference to Figure 1 , the heat exchange circuit 200 comprises an air extraction valve group 220 arranged on the downstream side of the intake end 230 and on the upstream side of the heat exchanger 210, and the air extraction valve group 220 is used to extract the gaseous medium at the intake end 230 to the heat exchanger 210. Analogous to the air extraction valve group 220 in the heat exchange circuit 200, an air extraction pump can be arranged in the circulation circuit 100.

[0086] Specifically, in the embodiment, the air extraction valve group 220 can provide suction force for the flow of the gaseous medium in the heat exchange circuit 200, so that the gaseous medium can flow from the intake end 230 to the heat exchanger 210 in a concentrated and high-speed manner, thereby facilitating to improve the efficiency of the gaseous medium flowing to the heat exchanger 210 and reducing the waiting time of the heat exchanger 210. Moreover, by providing suction force for the flow of the gaseous medium in the heat exchange circuit 200 through the air extraction valve group 220, the layout mode of the heat exchange circuit 200 can be simplified, and the layout volume of the heat exchange circuit 200 can be reduced. For example, the heat exchange circuit 200 can comprise a plurality of elbow structures, which are more space-saving than straight pipe structures. Under the suction action of the air extraction valve group 220, the gaseous medium can bypass the elbow and easily reach the heat exchanger 210, avoiding the accumulation of the gaseous medium at the elbow and preventing the elbow from affecting the flow efficiency of the gaseous medium.

[0087] In some embodiments, with reference to Figure 1The low-pressure cylinder 160 is arranged on the upstream side of the condenser 110, and the gaseous medium in the low-pressure cylinder 160 flows into the condenser 110, so that the condenser 110 condenses the gaseous medium into liquid medium.

[0088] Specifically, in the embodiment, the low-pressure cylinder 160 can be regarded as the end of the circulating loop 100, and the condenser 110 can be regarded as the beginning of the circulating loop 100. The low-pressure cylinder 160 is arranged on the upstream side of the condenser 110, so that the circulating loop 100 is connected in a closed mode. Since the gaseous medium is consumed in terms of heat energy and pressure energy after passing through each cylinder, the gaseous medium passing through the low-pressure cylinder 160 has the lowest heat energy and pressure energy. At this time, the low-pressure and low-heat gaseous medium can be condensed into liquid medium by the condenser 110, and then be pressurized and heated in the circulating loop 100 again. Finally, the high-temperature and high-pressure gaseous medium is obtained again, and is used for heat exchange, driving the cylinder to work, etc., so that the heating system 10 can continuously heat and generate electricity.

[0089] In some embodiments, referring to Figure 1 The heating system 10 includes a one-loop and a three-loop. The one-loop is connected with the steam generator 123, and is used for transferring heat to the steam generator 123. The three-loop is connected with the condenser 110, and is used for absorbing heat generated when the gaseous medium in the condenser 110 is condensed into liquid medium.

[0090] Specifically, in the embodiment, the heating system 10 provided by the application corresponds to a two-loop. The two-loop is connected with the one-loop and the three-loop, so that a large amount of heat generated by the nuclear reaction in the one-loop is used to heat the steam generator 123 in the two-loop, and the three-loop can absorb heat generated when the gaseous medium is condensed into liquid medium in the condenser 110. By using the above structure, the nuclear heat and natural resources can be used to the greatest extent, energy waste can be avoided, the environment can not be polluted, and environmental friendliness can be achieved.

[0091] In some embodiments, referring to Figure 1 The heat exchange loop 200 includes a first branch 240 and a second branch 250. The heat exchanger 210 is arranged between the first branch 240 and the second branch 250. The first branch 240 and the second branch 250 are both used for conveying flow medium, for example, the flow medium can be liquid medium or gaseous medium. The flow medium in the first branch 240 flows into the second branch 250 after passing through the heat exchanger 210, so that the temperature of the flow medium in the second branch 250 is higher than that of the flow medium in the first branch 240.

[0092] Specifically, in the embodiment, the first branch 240 and the second branch 250 can be connected to the civil supply side, the lower-temperature flow medium of the civil supply side can flow along the first branch 240 to the heat exchanger 210, and after heat exchange at the heat exchanger 210, the higher-temperature flow medium can flow along the second branch 250 to the civil supply side, so as to realize heating for the civil supply side.

[0093] Correspondingly, another embodiment of the present application also provides a heat load detection method of a heating system 10, which utilizes the heating system 10 provided in any of the above embodiments to detect the heat load, and the heat load detection method comprises the following steps: Figure 5

[0094] Step S100: The gaseous medium in the circulation loop 100 flows into the heat exchange loop 200, and after heat exchange at the heat exchanger 210 in the heat exchange loop 200, the gaseous medium is condensed into liquid medium.

[0095] Step S200: The liquid medium in the heat exchange loop 200 flows into the detection loop 300, and the liquid medium flows into the detection element 310 to complete flow detection at the detection element 310.

[0096] Specifically, in the embodiment, since the liquid medium is all formed by condensation of the gaseous medium at the heat exchanger 210, the flow of the liquid medium detected by the detection element 310 characterizes the change of the heating heat load at the heat exchanger 210, so that the heat load of the heating system 10 can be directly obtained according to the detection result of the detection element 310. The detection method of detecting the flow of the liquid medium is used to obtain the heat load, and based on the physical characteristics (for example, the relatively stable density and viscosity of the liquid) of the liquid, the change amount of the flow of the liquid medium can be more directly obtained, and the accuracy of the detection is improved.

[0097] The detection method provided in the embodiment has less measurement points and high measurement accuracy, and can provide accurate data for real-time metering of the external heat supply of the nuclear power plant. By using the detection method provided in the embodiment, on the one hand, the accuracy and real-time performance of the nuclear energy heating heat load identification are improved; on the other hand, the economy of the nuclear energy heating is improved.

[0098] In some embodiments, referring to Figure 1 Before the liquid medium flows into the detection element 310, the liquid medium is pressurized. For example, a pressurizing element 320 can be arranged on the upstream side of the detection element 310, and the pressurizing element 320 can be used to pressurize the liquid medium flowing into the detection element 310 in advance.

[0099] ​Specifically, in the embodiment, after being boosted, the liquid medium becomes single-phase pressurized subcooled water without steam, so that the flow measurement of the liquid medium is more accurate. The single-phase pressurized subcooled water does not flash after being depressurized by the flow measurement detection element 310, so that a smaller throttle orifice plate that can improve the measurement accuracy can be used for flow measurement, so that the measurement result is more accurate.

[0100] In some embodiments, with reference to Figure 2 , the detection element 310 generates detection data according to the flow detection result, and obtains the actual heat load of the heating system 10 based on the comparison between the detection data and the preset curve between the heating steam extraction amount and the heat load. It should be noted that the heat load here refers to the unit power under different steam extraction flow rates.

[0101] Specifically, in the embodiment, after accurately measuring the flow change of the liquid medium, the corresponding heating heat load can be directly obtained by searching the graph, which is simple and convenient.

[0102] For example, with reference to Figure 2 , taking the TMCR curve as an example, if the detection element 310 detects that the flow of the liquid medium flowing therethrough is 250 t / h, the corresponding heating steam extraction amount is 250 t / h, the corresponding unit power is 1200 MW, and the corresponding heat load is 1200 MW.

[0103] In some embodiments, the preset curve between the heating steam extraction amount and the heat load can be generated on a computer, and the detection element 310 can directly upload the flow detection result to the computer, so that the relationship between the flow detection result and the preset curve can be automatically analyzed by the computer, which is simple and efficient and avoids human error. Moreover, the above data can be stored in the computer for real-time tracing.

[0104] Thanks to the improvement of the heating system 10, the detection method of the embodiment has the same technical effects as the heating system 10, which will not be described here.

[0105] It should be noted that other undisclosed contents of the heating system 10 and the detection method provided by the present application can be referred to the prior art, which will not be described here.

[0106] The above is only the preferred embodiment of the present application, and does not limit the patent scope of the present application. Any equivalent structural transformation made by using the content of the present application specification and drawings, or direct / indirect application in other related technical fields is included in the patent protection scope of the present application.

Claims

1. A heating system, characterized in that, include: A circulation loop, wherein the circulation loop is filled with a gaseous medium; A heat exchange circuit, the heat exchange circuit including a heat exchanger, the heat exchanger being disposed on the downstream side of the circulation circuit, the heat exchanger being configured to receive a gaseous medium in the circulation circuit and condense the gaseous medium into a liquid medium; A detection circuit, comprising a detection element disposed on the downstream side of the heat exchanger, wherein the detection element is used to detect the flow rate of the liquid medium.

2. The heating system according to claim 1, characterized in that, The detection circuit includes a pressure boosting element, which is located downstream of the heat exchanger and upstream of the detection element. The pressure boosting element is used to boost the pressure of the liquid medium.

3. The heating system according to claim 2, characterized in that, The detection circuit includes a connecting pipe, and the detection element is connected to the downstream side of the boosting element through the connecting pipe. The detection element includes an orifice plate with flow holes, through which the liquid medium flows. The ratio B of the diameter of the flow passage hole to the diameter of the connecting pipe satisfies: 0.2 < B < 0.

6.

4. The heating system according to claim 2, characterized in that, The detection circuit includes a rectifier, which is located downstream of the boost element and upstream of the detection element.

5. The heating system according to claim 1, characterized in that, The circulation loop includes a condenser and a heater group. The heater group is located downstream of the condenser. The condenser is used to condense the gaseous medium into the liquid medium. The heater group is used to evaporate the liquid medium into the gaseous medium and raise the temperature of the gaseous medium to the target temperature. The heater assembly includes a first heater located near the condenser, and the detection circuit has a liquid outlet located downstream of the first heater.

6. The heating system according to claim 5, characterized in that, The heater assembly further includes a second heater, which is located downstream of the first heater. The liquid outlet is located downstream of the first heater and upstream of the second heater. The first heater is used to heat the liquid medium to a first heating temperature, and the second heater is used to heat the liquid medium to a second heating temperature, wherein the second heating temperature is higher than the first heating temperature.

7. The heating system according to claim 6, characterized in that, The first heating temperature T1 satisfies: 80℃≤T1≤90℃, and the second heating temperature T2 satisfies: 220℃≤T2≤230℃.

8. The heating system according to claim 6, characterized in that, The heater assembly includes a steam generator, which is located downstream of the second heater; The steam generator is used to evaporate the liquid medium into the gaseous medium.

9. The heating system according to claim 6, characterized in that, The heater assembly includes a steam generator located downstream of the second heater; the circulation loop includes a deaerator located downstream of the liquid outlet and upstream of the steam generator.

10. The heating system according to claim 6, characterized in that, The heater assembly includes a steam generator located downstream of the second heater; the circulation loop includes a generator and a plurality of pressure cylinders located downstream of the steam generator. The plurality of pressure cylinders are configured to absorb the gaseous medium formed by the evaporation of the steam generator and convert the thermal or pressure energy of the gaseous medium into mechanical energy to drive the generator.

11. The heating system according to claim 10, characterized in that, The plurality of pressure cylinders include at least a high-pressure cylinder, a medium-pressure cylinder, and a low-pressure cylinder. The medium-pressure cylinder is located downstream of the high-pressure cylinder, and the low-pressure cylinder is located downstream of the medium-pressure cylinder. The heat exchange circuit has an air inlet end, which is connected to the heat exchanger. The air inlet is located downstream of the intermediate-pressure cylinder and upstream of the low-pressure cylinder, and at least part of the gaseous medium in the intermediate-pressure cylinder flows to the heat exchanger through the air inlet.

12. The heating system according to claim 11, characterized in that, The heat exchange circuit includes an exhaust valve assembly, which is located downstream of the air inlet and upstream of the heat exchanger. The exhaust valve assembly is used to draw the gaseous medium at the air inlet to the heat exchanger.

13. The heating system according to claim 11, characterized in that, The low-pressure cylinder is located upstream of the condenser. The gaseous medium in the low-pressure cylinder flows into the condenser so that the condenser condenses the gaseous medium into the liquid medium.

14. The heating system according to claim 10, characterized in that, The heating system includes a primary circuit and a secondary circuit. The primary circuit is connected to the steam generator and is used to transfer heat to the steam generator. The secondary circuit is connected to the condenser and is used to absorb the heat generated when the gaseous medium in the condenser condenses into the liquid medium.

15. The heating system according to claim 1, characterized in that, The heat exchange circuit includes a first branch and a second branch, and the heat exchanger is disposed between the first branch and the second branch. Both the first branch and the second branch are used to transport the flowing medium. The flowing medium in the first branch flows to the second branch after passing through the heat exchanger, so that the temperature of the flowing medium in the second branch is higher than the temperature of the flowing medium in the first branch.

16. A method for detecting the heat load of a heating system, characterized in that, The detection method utilizes the heating system as described in any one of claims 1 to 15 to perform heat load detection, the detection method comprising: The gaseous medium in the circulation loop flows into the heat exchange loop, and after heat exchange is completed at the heat exchanger in the heat exchange loop, the gaseous medium condenses into a liquid medium. The liquid medium in the heat exchange circuit flows to the detection circuit, and the detection element detects the flow rate of the liquid medium.

17. The method for detecting the heat load of a heating system according to claim 16, characterized in that, The liquid medium is pressurized before it flows to the detection element.

18. The method for detecting the heat load of a heating system according to claim 16, characterized in that, Also includes: Based on the flow detection results of the detection element, detection data is generated. The actual heat load of the heating system is obtained by comparing the preset curve between the steam extraction volume and the heat load with the detection data.

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