Steam generating system and steam generating method

Abstract

The present application relates to the field of heat storage technology, and provides a steam generation system, including: a heat pump unit, used for heating and preparing high-temperature water of a fourth temperature, the high-temperature water is used to generate a first water vapor of a first pressure; a heat storage device, suitable for storing heat by electric heating during the heat storage period, and preparing a second water vapor of a second pressure by releasing heat during the steam generation period; an ejection device, having a high-pressure input end and a low-pressure input end, the high-pressure input end is used to input the second water vapor, and the low-pressure input end is used to input the first water vapor, the ejection device is configured to use the second water vapor to eject the first water vapor to form a third water vapor of a third temperature; wherein the second pressure is higher than the first pressure; the first water vapor has a first temperature, the second water vapor has a second temperature, and the second temperature is greater than the first temperature. The present application improves the overall energy efficiency of the steam generation system by utilizing the high energy efficiency characteristics of the heat pump unit and combining the ejection device. The present application also provides a steam generation method.

Description

Technical Field

[0001] The present application relates to the field of heat storage technology, and in particular to a steam generation system and a steam generation method. Background Art

[0002] In order to avoid the emission of combustion exhaust gas and utilize clean electricity and lower valley electricity prices, steam generation systems equipped with electric heating energy storage modules have gradually replaced combustion heating steam generation systems. Although the existing steam generation systems using electric heating energy storage modules can effectively utilize valley electricity for heat storage, and release heat and generate steam during flat or peak electricity periods, thus alleviating the pressure of electricity consumption during flat and peak electricity periods, the overall energy efficiency of the current steam generation systems using electric heating energy storage modules is low. Summary of the invention

[0003] In order to solve the above problems, the present application provides a steam generation system and a steam generation method, which are cleverly designed, and improve the overall energy efficiency of the steam generation system by utilizing the high energy efficiency characteristics of the heat pump unit and combining with an ejector device. In addition, it is convenient to upgrade the existing steam generation system to the steam generation system of the present application. The technical solutions adopted in the present application are as follows:

[0004] A steam generating system, comprising:

[0005] A heat pump unit, used for preparing high-temperature water at a fourth temperature, wherein the high-temperature water is used to generate a first water vapor at a first pressure; a heat storage device, suitable for storing heat by electric heating during a heat storage period, and preparing a second water vapor at a second pressure by releasing heat during a steam generation period; an ejection device, having a high-pressure input end and a low-pressure input end, wherein the high-pressure input end is used to input the second water vapor, and the low-pressure input end is used to input the first water vapor, and the ejection device is configured to eject the first water vapor using the second water vapor to form a third water vapor at a third temperature; wherein the second pressure is higher than the first pressure; the first water vapor has a first temperature, the second water vapor has a second temperature, and the second temperature is greater than the first temperature.

[0006] By utilizing the high energy efficiency of the heat pump unit and combining it with an ejector device, steam-steam ejection is used to improve the overall energy efficiency of the steam generation system.

[0007] In some embodiments, the steam generation system further includes: a flash tank connected to the heat pump unit, and configured to generate the first water vapor using the high temperature water.

[0008] A flash tank is used to generate the first water vapor, and a heat storage device is used to generate the second water vapor. That is to say, the first water vapor may be generated by a flash tank instead of a heat storage device, thereby achieving decoupling of the first water vapor and the heat storage device, which is beneficial to the design and commissioning of the first water vapor generating device and the design and commissioning of the heat storage device.

[0009] In some embodiments, the steam generating system further includes: a deionized water supply device for providing deionized water; wherein the heat pump unit is connected to the deionized water supply device, and the heat storage device is connected to the flash tank for generating the second water vapor using the saturated water in the flash tank; and / or the heat storage device is connected to the deionized water supply device for heating the deionized water to form the second water vapor.

[0010] By setting up a deionized water supply device, harmful components in the water, such as calcium, magnesium, chlorine and other ions, can be removed. These ions will form scale or chloride on the inner wall of the pipeline, causing pipeline corrosion and blockage. By connecting the heat storage device to the flash tank, the saturated water discharged from the flash tank is used to pass through the heat storage device to generate the second water vapor. Because the saturated water discharged from the flash tank is input by the heat pump unit, and the heat pump unit has high energy efficiency, and the temperature of the saturated water discharged from the flash tank is higher than the deionized water directly input into the heat storage device, this method improves the energy efficiency of the steam generation system compared to the heat storage device directly using deionized water to produce the second water vapor.

[0011] In some embodiments, the steam generation system further includes: a heat-insulating water storage device for storing the high-temperature water; the heat storage device is connected to the heat-insulating water storage device for generating the second water vapor using the high-temperature water; the heat storage device includes a plurality of heat storage modules, the plurality of heat storage modules include a first heat storage module, and during a steam generation period, the first heat storage module is used to generate the first water vapor using the high-temperature water.

[0012] By setting up a heat-insulating water storage device and connecting the heat-insulating water storage device to the heat storage device, the high-temperature water discharged from the heat-insulating water storage device is used to pass through the heat storage device to generate the second water vapor. Because the high-temperature water discharged from the heat-insulating water storage device is input by the heat pump unit, and the heat pump unit has high energy efficiency, and the temperature of the high-temperature water discharged from the heat-insulating water storage device is higher than the deionized water directly input into the heat storage device, this method improves the energy efficiency of the steam generation system compared to the heat storage device directly using deionized water to produce the second water vapor. In addition, the first water vapor can be generated by the first heat storage module in the heat storage device, and there is no need to set up a flash tank, which reduces the construction cost. In addition, by setting up a heat-insulating water storage device, the heat pump unit can use valley electricity to produce high-temperature water and store the high-temperature water in the heat-insulating water storage device, which can avoid the situation where the heat pump unit needs to work during the steam generation stage of the steam generation system, or reduce the power consumption pressure of the heat pump unit during the steam generation stage of the steam generation system, thereby reducing the power occupation of the heat pump unit during the flat power period or peak power period.

[0013] In some embodiments, the heat exchange pipes of at least two of the heat storage modules are configured to be switchable between being connected in parallel to form a steam generation path and being connected in series to form a steam generation path.

[0014] By configuring the heat exchange pipes of at least two heat storage modules to be switchable between parallel connection to form a steam generation path and series connection to form a steam generation path, the adaptability of the steam generation system to changes in the amount of steam required by the user side can be improved. For example, when the heat exchange pipes of two heat storage modules are connected in parallel, due to different parameter configurations of the two heat storage modules or heat release sequence problems, the two heat storage modules may have inconsistent temperatures. For example, one of them has a low temperature and can be used to heat high-temperature water, while the other has a high temperature and can be used to generate the second water vapor. At this time, the heat exchange pipes of the two heat storage modules can be switched to be connected in series, and the high-temperature water passes through the heat storage module with a lower temperature and then enters the heat storage module with a higher temperature. In this way, the amount of the second water vapor generated by the heat storage module with a higher temperature can be increased, that is, the ability of the heat storage module with a higher temperature to supply the second water vapor is improved.

[0015] In some embodiments, the first heat storage module has a heat exchange pipe and a first steam pipe, the heat exchange pipe is used to heat the incoming high-temperature water into the second water vapor, and the first steam pipe is led out from a set position of the heat exchange pipe for outputting the first water vapor.

[0016] By arranging the heat exchange pipe and the first steam pipe on the same heat storage module, the number of heat storage modules can be reduced, saving the construction cost and floor space of the heat storage device, compared with arranging the heat exchange pipe and the first steam pipe on different heat storage modules.

[0017] In some embodiments, the heat-insulating water storage device is suitable for storing high-temperature water with a pressure greater than one atmosphere, and the fourth temperature is greater than 100°C.

[0018] By configuring the heat-insulating water storage device to store high-temperature water with a pressure greater than one atmosphere and a temperature greater than 100°C, the high energy efficiency of the heat pump unit can be fully utilized, which is beneficial to improving the overall energy efficiency of the steam generation system.

[0019] In some embodiments, the steam generation system further includes: a desuperheater having a high temperature input end and a low temperature input end, wherein the high temperature input end is used to input the third water vapor, and the low temperature input end is used to input desuperheating water.

[0020] By providing a desuperheater, the temperature of the third water vapor output by the ejector device and then entering the desuperheater can be accurately adjusted, so that the temperature of the steam output to the user side is stable and meets the requirements.

[0021] In some embodiments, the desuperheated water includes the high-temperature water; and / or, the desuperheated water includes deionized water provided by a deionized water supply device.

[0022] By using the high-temperature water prepared by the heat pump unit for cooling water, the high energy efficiency of the heat pump unit can be fully utilized, which is beneficial to improving the overall energy efficiency of the steam generation system.

[0023] On the other hand, the present application also provides a steam generation system, comprising:

[0024] A heat pump unit for preparing high-temperature water at a fourth temperature; a heat storage device suitable for storing heat by electric heating during a heat storage period, and preparing a second water vapor of a second pressure by heating the high-temperature water during a steam generation period; an ejection device having a high-pressure input end and a low-pressure input end, the high-pressure input end being used to input the second water vapor, and the low-pressure input end being used to input the high-temperature water, the ejection device being configured to utilize the second water vapor to eject the high-temperature water to form a third water vapor of a third temperature.

[0025] By utilizing the high energy efficiency of the heat pump unit and combining it with an ejector device, the overall energy efficiency of the steam generation system is improved by using a vapor-liquid ejector. Compared with the vapor-steam ejector solution, the vapor-liquid ejector solution does not need to generate the first water vapor, thereby simplifying the system configuration. For example, there is no need for a flash tank, and there is no need to configure a pipeline for generating the first water vapor for the heat storage module.

[0026] In addition, the present application also provides a steam generation method, comprising the steps of:

[0027] The heat pump unit prepares high-temperature water at a fourth temperature; the high-temperature water is used to prepare a first water vapor at a first pressure; the heat storage device stores heat by electric heating during a heat storage period; the heat storage device prepares a second water vapor at a second pressure by releasing heat during a steam generation period; the ejection device ejects the first water vapor by using the second water vapor to form a third water vapor at a third temperature; wherein the second pressure is higher than the first pressure; the first water vapor has a first temperature, the second water vapor has a second temperature, and the second temperature is greater than the first temperature.

[0028] The present application provides a steam generation system and a steam generation method, which have at least one of the following beneficial effects:

[0029] 1. The present application provides a steam generation system which utilizes the high energy efficiency of a heat pump unit and combines it with an ejector device to perform steam-steam ejection, thereby improving the overall energy efficiency of the steam generation system.

[0030] 2. The present application provides a steam generating system, which generates a first water vapor by a flash tank and generates a second water vapor by a heat storage device. That is to say, the first water vapor may not be generated by the heat storage device but by the flash tank, thereby achieving decoupling of the first water vapor and the heat storage device, which is beneficial to the design and commissioning of the first water vapor generating device and the design and commissioning of the heat storage device.

[0031] 3. The steam generation system provided in the present application can remove harmful components in water, such as calcium, magnesium, chlorine and other ions, by setting up a deionized water supply device. These ions will form scale or chloride on the inner wall of the pipeline, thereby causing corrosion and blockage of the pipeline.

[0032] 4. The present application provides a steam generation system, which generates a second water vapor by connecting a heat storage device to a flash tank and utilizing saturated water discharged from the flash tank through the heat storage device. Because the saturated water discharged from the flash tank is input by a heat pump unit, and the heat pump unit has high energy efficiency, and in addition, the temperature of the saturated water discharged from the flash tank is higher than that of the deionized water directly input into the heat storage device, this method improves the energy efficiency of the steam generation system compared to the heat storage device directly utilizing deionized water to produce the second water vapor.

[0033] 5. A steam generation system provided by the present application, by providing a heat preservation water storage device, and connecting the heat preservation water storage device to a heat storage device, using the high-temperature water discharged from the heat preservation water storage device to pass through the heat storage device to generate a second water vapor, because the high-temperature water discharged from the heat preservation water storage device is input by the heat pump unit, and the heat pump unit has a high energy efficiency, and in addition, the temperature of the high-temperature water discharged from the heat preservation water storage device is higher than the deionized water directly input into the heat storage device, so compared with the heat storage device directly using deionized water to produce the second water vapor, this method improves the energy efficiency of the steam generation system. In addition, the first water vapor can be generated by the first heat storage module in the heat storage device, and there is no need to set up a flash tank, which reduces the construction cost. In addition, by providing a heat preservation water storage device, the heat pump unit can use valley electricity to produce high-temperature water, and store the high-temperature water in the heat preservation water storage device, which can avoid the situation where the heat pump unit of the steam generation system needs to work during the steam generation stage, or can reduce the power consumption pressure of the heat pump unit of the steam generation system during the steam generation stage, thereby reducing the power occupation of the heat pump unit during the flat power period or peak power period.

[0034] 6. A steam generation system provided in the present application can improve the adaptability of the steam generation system to changes in the amount of steam required by the user side by configuring the heat exchange pipes of at least two heat storage modules to be switchable between parallel connection to form a steam generation path and series connection to form a steam generation path. For example, when the heat exchange pipes of two heat storage modules are connected in parallel, due to different parameter configurations of the two heat storage modules or heat release sequence problems, the two heat storage modules may have inconsistent temperatures. For example, one of them has a low temperature and can be used to heat high-temperature water, while the other has a high temperature and can be used to generate a second water vapor. At this time, the heat exchange pipes of the two heat storage modules can be switched to be connected in series, and the high-temperature water passes through the heat storage module with a lower temperature and then enters the heat storage module with a higher temperature. In this way, the amount of the second water vapor generated by the heat storage module with a higher temperature can be increased, that is, the ability of the heat storage module with a higher temperature to supply the second water vapor is improved.

[0035] 7. The steam generating system provided in the present application can reduce the number of heat storage modules and save the construction cost and floor space of the heat storage device by setting the heat exchange pipe and the first steam pipe together on the same heat storage module, compared with setting the heat exchange pipe and the first steam pipe on different heat storage modules.

[0036] 8. The steam generation system provided in the present application can give full play to the high energy efficiency of the heat pump unit by configuring the heat-insulating water storage device to have the function of storing high-temperature water with a pressure greater than one atmosphere and a temperature higher than 100°C, thereby facilitating the improvement of the overall energy efficiency of the steam generation system.

[0037] 9. The steam generating system provided in the present application can precisely adjust the temperature of the third water vapor output by the ejector device and then entering the desuperheater by setting a desuperheater, so that the temperature of the steam output to the user side is stable and meets the requirements.

[0038] 10. The steam generation system provided in the present application can give full play to the high energy efficiency of the heat pump unit by using the high temperature water prepared by the heat pump unit for cooling water, which is beneficial to improving the overall energy efficiency of the steam generation system.

[0039] 11. The application provides a steam generation system, which improves the overall energy efficiency of the steam generation system by utilizing the high energy efficiency characteristics of the heat pump unit and combining it with an ejector device, and adopts a vapor-liquid ejector method for ejection. Compared with the steam-steam ejector solution, the vapor-liquid ejector solution does not need to generate the first water vapor, thereby simplifying the system configuration, for example, there is no need for a flash tank, and there is no need to configure a pipeline for generating the first water vapor for the heat storage module. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] The preferred embodiments will be described below in a clear and understandable manner in conjunction with the accompanying drawings to further illustrate the above characteristics, technical features, advantages and implementation methods of a steam generation system and a steam generation method:

[0041] Figure 1 is a system structure diagram of the first embodiment of the present application;

[0042] Figure 2 is a system structure diagram of the second embodiment of the present application;

[0043] Figure 3 is a system structure diagram of the third embodiment of the present application;

[0044] Figure 4 is a system structure diagram of the fourth embodiment of the present application;

[0045] Figure 5 is a system structure diagram of the fifth embodiment of the present application;

[0046] Figure 6 is a system structure diagram of the sixth embodiment of the present application;

[0047] Figure 7 It is a system structure diagram of the seventh embodiment of the present application. DETAILED DESCRIPTION

[0048] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the specific implementation methods of the present application will be described below with reference to the accompanying drawings. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings and other implementation methods can be obtained based on these drawings without creative work.

[0049] In order to simplify the drawings, only the parts related to the present application are schematically shown in each figure, and they do not represent the actual structure of the product. In addition, in order to simplify the drawings and facilitate understanding, in some figures, only one of the parts with the same structure or function is schematically drawn or marked. In this article, "one" not only means "only one", but also means "more than one".

[0050] It should be further understood that the term “and / or” used in the specification and appended claims refers to any combination and all possible combinations of one or more of the associated listed items, and includes these combinations.

[0051] In this document, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0052] In addition, in the description of the present application, the terms "first", "second", etc. are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0053] refer to Figure 1-Figure 7 The present application provides a steam generation system, comprising: a heat pump unit, for preparing high-temperature water at a fourth temperature, the high-temperature water being used to generate a first water vapor at a first pressure; a heat storage device, suitable for storing heat by electric heating during a heat storage period, and preparing a second water vapor at a second pressure by releasing heat during a steam generation period; an ejection device, having a high-pressure input end and a low-pressure input end, the high-pressure input end being used to input the second water vapor, and the low-pressure input end being used to input the first water vapor, the ejection device being configured to eject the first water vapor using the second water vapor to form a third water vapor at a third temperature; wherein the second pressure is higher than the first pressure; the first water vapor has a first temperature, the second water vapor has a second temperature, and the second temperature is greater than the first temperature.

[0054] Specifically, the heat pump unit can be Figure 1-Figure 7 The waste heat source heat pump unit shown in the figure (including waste hot water heat pump unit, waste heat gas heat pump unit, etc.) can also be a geothermal heat pump unit (including surface water heat pump unit, groundwater heat pump unit, soil source heat pump, etc.), or a transcritical carbon dioxide heat pump unit, etc. It is understood that the types of heat pump units listed above should not be regarded as limiting the specific types of heat pump units in this application. The ejector device refers to Figure 1-Figure 7 The ejector shown in .

[0055] In addition, the heat storage material in the heat storage device of the present application may be a molten salt, such as a molten salt formed by mixing 50% sodium nitrate and 50% potassium nitrate, or a molten salt formed by mixing 60% sodium nitrate and 40% potassium nitrate, or a low melting point molten salt disclosed in the patent with application number CN201911219662 (melting point as low as about 80°), or a multi-component mixed molten salt disclosed in the patent with application number CN202311105206 (melting point as low as 47.3°), or a solid heat storage medium, such as ceramsite, metal balls, metal blocks, corundum balls, ore, glass, etc. It should be noted that the heat storage material can also be a heat storage brick. The heat storage material in the heat storage device may be a combination of one or more of the above example materials. It is understood that the types of heat storage materials listed above should not be regarded as limitations on the specific types of heat storage materials in this application.

[0056] The heat storage device generally includes an electric heating device, a storage container and a heat exchange pipe. The storage container is filled with a heat storage material. The electric heating device is used to heat the heat storage material so that the heat storage material stores thermal energy. The heat exchange pipe uses the thermal energy of the heat storage material to heat the water or steam flowing through the heat exchange pipe. The specific structure of the heat storage device is a prior art and is not the focus of protection of this application, so it will not be described in detail here.

[0057] In this application, the high energy efficiency characteristics of the heat pump unit are utilized, and combined with the injection device, steam-steam injection is used to improve the overall energy efficiency of the steam generation system.

[0058] refer to Figure 1-Figure 3 In one embodiment, the steam generation system further comprises a flash tank, which is connected to the heat pump unit, and the flash tank generates the first water vapor using the high temperature water output by the heat pump unit. In other embodiments, the first water vapor may be generated by using a heat storage device instead of a flash tank (see Figure 4-6 ). The first water vapor is generated by a flash tank, and the second water vapor is generated by a heat storage device. That is to say, the first water vapor may not be generated by the heat storage device but by the flash tank, thereby realizing the decoupling of the first water vapor and the heat storage device, which is beneficial to the design and commissioning of the first water vapor generating device and the design and commissioning of the heat storage device.

[0059] For the above-mentioned technical solution with a flash tank, in a specific embodiment, refer to Figure 1-Figure 3 The heat storage device includes three heat storage modules (referring to Figure 1-Figure 3 The #1 heat storage device, #2 heat storage device, and #3 heat storage device shown in the figure are all capable of generating second steam. The second steam generated by the three heat storage modules is passed to the ejector device (referring to Figure 1-Figure 3 It is understandable that when there is only one heat storage module capable of providing the second water vapor, there is no need to set up a steam cylinder, but the second water vapor generated by the single heat storage module is directly directed to the ejector (referring to Figure 1-Figure 3 The ejector shown in FIG.

[0060] refer to Figure 2 , Figure 3 In one embodiment, the steam generating system further includes a deionized water supply device, which is used to provide deionized water. The first solution: the heat pump unit is connected to the deionized water supply device, and the heat storage device is connected to the flash tank, and the heat storage device uses the saturated water output by the flash tank to generate the second water vapor; the second solution: the heat storage device is connected to the deionized water supply device, and is used to heat the deionized water to form the second water vapor. Only one of the first solution and the second solution can be set in the steam generating system, or both solutions can be set at the same time. The deionized water supply device refers to Figure 1-Figure 7 It is understandable that a pure water tank for storing deionized water may also be provided in the first and second solutions, and the pure water tank supplies the required deionized water to the heat pump unit or the heat storage device.

[0061] It is understandable that by providing a deionized water supply device, harmful components in the water, such as calcium, magnesium, chlorine and other ions, can be removed. These ions will form scale or chloride on the inner wall of the pipeline, thereby causing pipeline corrosion and blockage. In the first scheme, by connecting the heat storage device to the flash tank, the saturated water discharged from the flash tank is used to pass through the heat storage device to generate the second water vapor. Because the saturated water discharged from the flash tank is input by the heat pump unit, and the heat pump unit has a high energy efficiency, and the temperature of the saturated water discharged from the flash tank is higher than the deionized water directly input into the heat storage device in the second scheme, this method improves the energy efficiency of the steam generation system compared to the second scheme in which the heat storage device directly uses deionized water to produce the second water vapor.

[0062] refer to Figure 3In one embodiment, a preheating circulation pipeline is provided between the heat pump unit and the heat storage device, and the high-temperature water output by the heat pump unit is used to preheat the heat storage material in the heat storage device. After the high-temperature water preheats the heat storage material, it flows back into the heat pump unit, forming a circulation preheating of the heat storage device by the heat pump unit. This can reduce the power consumption pressure of the heat storage device when storing heat. In addition, the energy efficiency of the heat pump unit is higher than that of the heat storage device, which can reduce the power consumption of the entire steam generation system and improve the energy efficiency of the steam generation system.

[0063] Unlike the related technical solutions with flash tanks, Figure 4-Figure 7 In one embodiment, the steam generation system further comprises a heat preservation water storage device, which refers to Figure 4-Figure 7 The heat-insulating water storage tank shown in the figure is used to store the high-temperature water; the heat storage device is connected to the heat-insulating water storage device, and the heat storage device uses the high-temperature water output by the heat-insulating water storage device to generate the second water vapor; the heat storage device includes a plurality of heat storage modules (e.g. Figure 4-Figure 7 The plurality of heat storage modules include a first heat storage module (e.g., a heat storage device #3, a heat storage device #2, and a heat storage device #1). Figure 4-Figure 7 #3 heat storage device shown in ), during the steam generation period, the first heat storage module is used to generate the first water vapor using the high temperature water, and the other heat storage modules are used to generate the second water vapor using the high temperature water.

[0064] It can be understood that by setting up a heat-insulating water storage device and connecting the heat-insulating water storage device to the heat storage device, the high-temperature water discharged from the heat-insulating water storage device is used to pass through the heat storage device to generate the second water vapor, because the high-temperature water discharged from the heat-insulating water storage device is input by the heat pump unit, and the heat pump unit has a high energy efficiency. In addition, the temperature of the high-temperature water discharged from the heat-insulating water storage device is higher than the deionized water directly input into the heat storage device. Therefore, compared with the heat storage device directly using deionized water to produce the second water vapor, this method improves the energy efficiency of the steam generation system. In addition, the first water vapor can be generated by the first heat storage module in the heat storage device, and there is no need to set up a flash tank, which reduces the construction cost. In addition, by setting up a heat-insulating water storage device, the heat pump unit can use valley electricity to produce high-temperature water and store the high-temperature water in the heat-insulating water storage device, which can avoid the situation where the heat pump unit needs to work during the steam generation stage of the steam generation system, or reduce the power consumption pressure of the heat pump unit during the steam generation stage of the steam generation system, thereby reducing the power occupation of the heat pump unit during the flat power period or the peak power period.

[0065] For the above-mentioned technical solution with a heat preservation water storage device, in a specific embodiment, refer to Figure 4-Figure 6 The heat storage device includes at least two heat storage modules (referring to Figure 4-Figure 6The #2 heat storage device and #3 heat storage device shown in the figure are both capable of generating the second steam. The second steam generated by the two heat storage modules is passed to the ejector device (referring to Figure 4-Figure 6 It is understandable that when there is only one heat storage module capable of providing the second water vapor, there is no need to set up a steam cylinder, but the second water vapor generated by the single heat storage module is directly directed to the ejector (referring to Figure 4-Figure 6 The ejector shown in FIG.

[0066] In a specific embodiment, referring to Figure 4 , the first heat storage module (e.g. Figure 4 The heat storage device #3 shown in FIG. 1 is only used to generate the first water vapor, while other heat storage modules (such as Figure 4 The #2 heat storage device and #1 heat storage device shown in FIG. 1 are only used to generate the second water vapor. In another specific embodiment, referring to Figure 6 , the first heat storage module (e.g. Figure 4 The #3 heat storage device shown in FIG. 1 has a heat exchange pipe and a first steam pipe, wherein the heat exchange pipe is used to heat the inflowing high-temperature water into the second steam, and the first steam pipe is led out from a set position of the heat exchange pipe to output the first steam. It is understandable that in Figure 6 In the embodiment shown, the first steam pipe is part of the heat exchange pipe, or the first steam pipe and the heat exchange pipe have a common heat exchange section, the heat exchange path of the heat exchange pipe is longer, and the heat exchange path of the first steam pipe is shorter. Figure 6 In the embodiment shown, the first heat storage module (eg Figure 4 The heat storage device #3 shown in FIG) can be used not only to generate the first water vapor, but also to generate the second water vapor at the same time, while other heat storage modules (such as Figure 6 The #2 heat storage device and #1 heat storage device shown in the figure are only used to generate the second water vapor. In other embodiments, the first steam pipeline and the heat exchange pipeline arranged on the first heat storage module can be independent of each other.

[0067] It is easy to understand that by arranging the heat exchange pipe and the first steam pipe on the same heat storage module, compared with arranging the heat exchange pipe and the first steam pipe on different heat storage modules, the number of heat storage modules can be reduced, saving the construction cost and floor space of the heat storage device.

[0068] refer to Figure 5 In one embodiment, at least two of the heat storage modules (e.g. Figure 5The heat exchange pipes of the #3 heat storage device and the #2 heat storage device shown in the figure are configured to be switchable between parallel connection to form a steam generation path and series connection to form a steam generation path. It should be noted that by configuring the heat exchange pipes of at least two heat storage modules to be switchable between parallel connection to form a steam generation path and series connection to form a steam generation path, the adaptability of the steam generation system to changes in the amount of steam required by the user side can be improved. For example, when the heat exchange pipes of two heat storage modules are connected in parallel, due to different parameter configurations of the two heat storage modules or problems with the heat release sequence, the two heat storage modules may have inconsistent temperatures, such as one of them has a low temperature (for example Figure 5 The #3 heat storage device shown in the figure can be used to heat high temperature water, while the other high temperature (e.g. Figure 5 The #2 heat storage device shown in the figure can be used to generate the second water vapor. At this time, the heat exchange pipes of the two heat storage modules can be switched to be connected in series, and the high-temperature water passes through the heat storage module with a lower temperature (e.g. Figure 5 The heat storage device #3 shown in FIG) then enters a higher temperature heat storage module (e.g. Figure 5 #2 heat storage device shown in the figure), which can increase the amount of the second water vapor generated by the heat storage module with a higher temperature, that is, improve the ability of the heat storage module with a higher temperature to supply the second water vapor.

[0069] refer to Figure 5 In one embodiment, the heat-insulating water storage device is suitable for storing high-temperature water with a pressure greater than one atmosphere, and the fourth temperature is greater than 100°C. By setting the heat-insulating water storage device to have the function of storing high-temperature water with a pressure greater than one atmosphere and a temperature greater than 100°C, the high energy efficiency of the heat pump unit can be fully utilized, which is beneficial to the improvement of the overall energy efficiency of the steam generation system. The higher the pressure and temperature of the high-temperature water, the less heat the heat storage device needs to heat the high-temperature water into the second water vapor, thereby reducing the power consumption pressure of the heat storage device, which is beneficial to improving the overall energy efficiency of the steam generation system.

[0070] refer to Figure 1-Figure 7 In one embodiment, the steam generation system further comprises a desuperheater, which has a high temperature input end and a low temperature input end, wherein the high temperature input end is used to input the third water vapor, and the low temperature input end is used to input desuperheating water. By providing a desuperheater, the temperature of the third water vapor output by the ejector device and then entering the desuperheater can be accurately adjusted, so that the temperature of the steam output to the user side is stable and meets the requirements. Figure 1-Figure 6 In the embodiment shown, the cooling water is deionized water provided by the deionized water supply device. In other embodiments, the cooling water is saturated water provided by a flash tank or high-temperature water provided by a heat-insulating water storage device or high-temperature water directly provided by a heat pump unit. Figure 7In the illustrated embodiment, the heat preservation water storage device can provide cooling water for the desuperheater, and the deionized water supply device can also provide cooling water for the desuperheater. It can be understood that by using the saturated water provided by the flash tank or the high-temperature water provided by the heat preservation water storage device or the high-temperature water directly provided by the heat pump unit as cooling water, the high energy efficiency of the heat pump unit can be fully utilized, which is beneficial to the improvement of the overall energy efficiency of the steam generation system.

[0071] In order to better illustrate the beneficial effects of this application, Figure 1 The embodiment shown is used for explanation: if there is a factory with a large amount of waste heat, 0.6Mpa, 180℃ superheated steam (i.e., the third water vapor) is needed. First, the waste heat source heat pump unit uses the waste heat of the factory to produce 100t / h, 0.5Mpa, 140℃ high-temperature water, and 1.3t / h, 0.3Mpa, 133℃ saturated steam (i.e., the first water vapor) can be obtained by flash evaporation in a flash tank. The remaining 98.7t / h saturated water plus 1.3t / h, 15℃ make-up water (supplied by a deionized water supply device) are returned to the heat pump unit for heat absorption. The heating power of the heat pump unit is about 1MW.

[0072] Next, construct the ejector. Since the target gas pressure is 0.6MPa, the ejected gas (i.e., the first water vapor) pressure is 0.3MPa, that is, the ejector compression ratio is 2. According to calculations, when the expansion ratio is 10, the ejection coefficient is 0.5, that is, the ejected gas (i.e., the second water vapor) pressure needs to be 3MPa, and the flow rate is 2.6t / h.

[0073] The heat storage device can easily output 3MPa, 250℃ superheated steam as ejection steam (i.e., second steam) by adjusting the feed water pump pressure. That is, the 2.6t / h, 3Mpa, 250℃ steam (i.e., second steam) generated by the heat storage device ejects the 1.3t / h, 0.3Mpa, 133℃ steam (i.e., first steam) generated by the flash tank to finally obtain 3.9t / h, 0.6Mpa, 180℃ high-temperature steam (i.e., third steam).

[0074] The ejected gas and the ejected gas form a final mixed gas in a ratio of 1:0.5. Since the ejected gas is generated by the heat pump unit, if the COP (energy efficiency ratio) of the heat pump unit is 3, the power consumption of this 0.5 portion of gas is only 0.17, that is, the energy saving is 1-(1+0.17) / (1+0.5)=22% compared with the solution of only using a heat storage device to generate high-temperature steam of about 0.6Mpa and 180°C (that is, the third water vapor). If the 90% heat storage efficiency of the heat storage device is considered, the energy saving is even greater.

[0075] According to the above parameters, it takes 840kWh of electricity to produce 1 ton of 0.6Mpa, 180℃ steam using only the heat storage device. After adopting the ejection technology, 1 / (1+0.5) ton, 3Mpa, 250℃ steam (i.e. the second water vapor) out of 1 ton of steam is provided by the heat storage device, consuming 570kWh of electricity; 0.5 / (1+0.5) ton, 0.3Mpa, 133℃ steam (i.e. the first water vapor) is provided by the heat pump unit through flash evaporation. Based on the COP (energy efficiency ratio) of 3, the electricity consumption is 80kWh, and the total electricity consumption is 650kWh, which is 22% lower than 840kWh.

[0076] If the ejector compression ratio decreases (the steam pressure required by the user side decreases or the pressure of the saturated steam provided by the heat pump unit increases) and the expansion ratio increases (the heat storage device provides ejection steam at a higher pressure), the ejector coefficient will increase, so that the same flow of ejection steam (i.e., the second water vapor) can eject more saturated steam (i.e., the first water vapor), that is, the energy proportion of saturated steam will be greater, so the energy saving effect will be more significant. In addition, if the COP (energy efficiency ratio) of the heat pump unit is improved, the energy saving effect will also be improved.

[0077] refer to Figure 7 The present application also provides a steam generation system, including: a heat pump unit, the heat pump unit is used to prepare high-temperature water at a fourth temperature; a heat storage device, suitable for storing heat by electric heating during the heat storage period, and preparing a second water vapor of a second pressure by heating the high-temperature water during the steam generation period; an ejection device, having a high-pressure input end and a low-pressure input end, the high-pressure input end is used to input the second water vapor, and the low-pressure input end is used to input the high-temperature water, the ejection device is configured to use the second water vapor to eject the high-temperature water to form a third water vapor of a third temperature. Figure 1-Figure 6 The embodiment shown is different in that Figure 7 In the embodiment shown, vapor-liquid injection can be achieved by high-temperature water and the second water vapor without generating the first water vapor. By utilizing the high energy efficiency of the heat pump unit and combining the injection device, the vapor-liquid injection method is used for injection, thereby improving the overall energy efficiency of the steam generation system. Compared with the steam-steam injection scheme, the vapor-liquid injection scheme does not need to generate the first water vapor, thereby simplifying the system configuration, for example, there is no need for a flash tank, and there is no need to configure a pipeline for generating the first water vapor for the heat storage module.

[0078] In addition, the present application also provides a steam generation method, comprising the steps of: a heat pump unit preparing high-temperature water at a fourth temperature; using the high-temperature water to prepare a first water vapor at a first pressure; a heat storage device storing heat by electric heating during a heat storage period; the heat storage device preparing a second water vapor at a second pressure by releasing heat during a steam generation period; an ejection device ejecting the first water vapor by using the second water vapor to form a third water vapor at a third temperature; wherein the second pressure is higher than the first pressure; the first water vapor has a first temperature, the second water vapor has a second temperature, and the second temperature is greater than the first temperature.

[0079] It should be noted that the above embodiments can be freely combined as needed. The above are only preferred implementations of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present application, and these improvements and modifications should also be regarded as the protection scope of the present application.

Claims

1. A steam generating system, characterized in that: include: A heat pump unit, used for preparing high-temperature water at a fourth temperature, wherein the high-temperature water is used for generating first water vapor at a first pressure; A heat storage device, adapted to store heat by electric heating during a heat storage period, and to prepare a second water vapor of a second pressure by releasing heat during a steam generation period; an ejector device, comprising a high-pressure input end and a low-pressure input end, wherein the high-pressure input end is used to input the second water vapor, and the low-pressure input end is used to input the first water vapor, and the ejector device is configured to eject the first water vapor using the second water vapor to form third water vapor at a third temperature; wherein the second pressure is higher than the first pressure; The first water vapor has a first temperature, and the second water vapor has a second temperature, and the second temperature is greater than the first temperature.

2. The steam generating system according to claim 1, characterized in that: Also includes: A flash tank is connected to the heat pump unit and is used to generate the first water vapor using the high-temperature water.

3. The steam generating system according to claim 2, characterized in that: Also includes: A deionized water supply device, used for providing deionized water; Wherein, the heat pump unit is connected to the deionized water supply device, and the heat storage device is connected to the flash tank, for generating the second water vapor by using the saturated water in the flash tank; and / or, The heat storage device is connected to the deionized water supply device and is used to heat the deionized water to form the second water vapor.

4. The steam generating system according to claim 1, characterized in that: Also includes: A heat-insulating water storage device, used for storing the high-temperature water; The heat storage device is connected to the heat-insulating water storage device and is used to generate the second water vapor using the high-temperature water; The heat storage device includes a plurality of heat storage modules, and the plurality of heat storage modules include a first heat storage module. In a steam generation period, the first heat storage module is used to generate the first water vapor using the high-temperature water.

5. The steam generating system according to claim 4, characterized in that: The heat exchange pipes of at least two of the heat storage modules are configured to be switchable between being connected in parallel to form a steam generation passage and being connected in series to form a steam generation passage.

6. The steam generating system according to claim 4, characterized in that: The first heat storage module has a heat exchange pipe and a first steam pipe. The heat exchange pipe is used to heat the inflowing high-temperature water into the second water vapor. The first steam pipe is led out from a set position of the heat exchange pipe and is used to output the first water vapor.

7. The steam generating system according to claim 4, characterized in that: The heat-insulating water storage device is suitable for storing high-temperature water with a pressure greater than one atmosphere, and the fourth temperature is greater than 100°C.

8. The steam generating system according to any one of claims 1 to 7, characterized in that: Also includes: The desuperheater has a high temperature input end and a low temperature input end, wherein the high temperature input end is used to input the third water vapor, and the low temperature input end is used to input desuperheating water.

9. The steam generating system according to claim 8, characterized in that: The desuperheated water includes the high-temperature water; and / or, The desuperheated water includes deionized water provided by a deionized water supply device.

10. A steam generating system, characterized in that: include: A heat pump unit for preparing high-temperature water of the fourth temperature; A heat storage device, adapted to store heat by electric heating during a heat storage period, and to prepare a second steam at a second pressure by heating the high-temperature water during a steam generation period; The ejection device has a high-pressure input end and a low-pressure input end, the high-pressure input end is used to input the second water vapor, and the low-pressure input end is used to input the high-temperature water. The ejection device is configured to use the second water vapor to eject the high-temperature water to form a third water vapor of a third temperature.

11. A method for generating steam, characterized in that: Includes steps: The heat pump unit prepares high-temperature water of the fourth temperature; Using the high temperature water to prepare first steam at a first pressure; The heat storage device stores heat by electric heating during the heat storage period; The heat storage device prepares second water vapor of second pressure by releasing heat during the steam generation period; The ejection device ejects the first water vapor using the second water vapor to form third water vapor at a third temperature; wherein the second pressure is higher than the first pressure; The first water vapor has a first temperature, and the second water vapor has a second temperature, and the second temperature is greater than the first temperature.

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