Energy storage coupling heat pump heat supply system and configuration method thereof

Abstract

According to the energy storage coupling heat pump heat supply system and the configuration method thereof, the total enthalpy value is distributed into the first enthalpy increment provided by heat pump heating and the second enthalpy increment provided by the energy storage device by quantifying the heat load requirement. And on the basis of the transformer capacity, the waste heat resources and the electricity price strategy in the valley electricity period, the payback periods of the single fused salt heat supply scheme and the energy storage coupling heat pump heat supply scheme are calculated respectively and compared with the expected payback period of a user, and the optimal scheme is selected. According to the method, the running power proportion of the heat pump device and the energy storage device is dynamically adjusted, the pressurizing heat preservation water tank, the low-melting-point molten salt and the deep heat release technology are combined, the economical efficiency and energy efficiency of the system are improved, and the method is suitable for various heat supply scenes.

Description

Technical Field

[0001] The present invention relates to the field of heating technology, and in particular to an energy storage coupled heat pump heating system and a configuration method thereof, which is suitable for efficient heating needs in industrial and commercial scenarios and can optimize the coordinated operation of a heat pump and an energy storage device under various operating conditions. Background Art

[0002] With the improvement of energy conservation, emission reduction and energy efficiency requirements, the application of heat pump and energy storage technology in heating systems has gradually increased. In the existing technology, a single energy storage device or heat pump heating system has deficiencies in dealing with peak loads, valley electricity utilization and improving the overall efficiency of the system. For example, although the molten salt energy storage device can use valley electricity with low electricity prices to store heat, it is large in size, has a high initial investment, and has poor load adaptability. Although the heat pump device has high energy efficiency, the operation of a single heat pump cannot fully utilize the external low-level heat source and is easily limited by the transformer capacity.

[0003] In addition, existing systems usually do not fully combine user needs, external resource conditions (such as plant waste heat and meteorological conditions) and economic factors (such as electricity price differences and investment payback period) for dynamic optimization, resulting in high operating costs and a lack of systematic consideration of initial investment and payback period. Therefore, how to effectively combine heat pumps and energy storage devices and improve the overall efficiency and economy of the heating system through optimized configuration methods is an urgent problem to be solved. Summary of the invention

[0004] The present invention aims to solve the problems of low energy efficiency, long payback period and insufficient load adaptability in existing heating systems, and provides an energy storage coupled heat pump heating system and a configuration method thereof. Through a dynamic optimization method based on enthalpy distribution, the total enthalpy demand of the heating system is reasonably allocated to the heat pump device and the energy storage device, and the operation mode and power distribution are optimized in combination with the factory's waste heat resources, the transformer capacity during off-peak hours and the user's expected payback period. The present invention can dynamically adjust the operating status of the heat pump and the energy storage device according to the real-time load demand, reduce the operating cost and shorten the payback period while ensuring efficient heating, and is suitable for a variety of heating scenarios.

[0005] According to a first aspect of the present invention, a configuration method of an energy storage coupled heat pump heating system is provided, comprising the following steps:

[0006] According to the heat load demand during the heating period, the total enthalpy value H of the required heat carrier is quantified;

[0007] The investment payback period of the single molten salt heating scheme and the energy storage coupled heat pump heating scheme is calculated respectively, where:

[0008] The single molten salt heating solution calculates the payback period through the initial investment and the savings in operating costs;

[0009] The energy storage coupled heat pump heating solution allocates the total enthalpy value H required by the user into the first enthalpy increment h provided by the heat pump device and the second enthalpy increment (Hh) provided by the energy storage device, and calculates the investment payback period in combination with the system operation efficiency and electricity price;

[0010] The payback periods of the single molten salt heating scheme and the energy storage coupled heat pump heating scheme are compared with the target payback period set by the user to determine the best scheme.

[0011] In some technical solutions, the transformer capacity during off-peak hours is further considered in the calculation of the payback period, and the following steps are included:

[0012] When the transformer capacity is sufficient, it is implemented according to the quantification of heating demand and enthalpy distribution;

[0013] When the transformer capacity is insufficient, the investment payback period with and without capacity expansion is calculated separately, where:

[0014] In case of capacity expansion, add the transformer expansion cost to the initial investment;

[0015] Without capacity expansion, the allowable steam supply can be inferred from the transformer surplus capacity to calculate the investment payback period of partial replacement heating;

[0016] Compare the payback period of expanding capacity with that of not expanding capacity, and choose the shorter option.

[0017] In some technical solutions, the processing without capacity expansion includes:

[0018] Use the surplus capacity of the transformer during off-peak hours to reversely calculate the allowable steam supply and make partial substitution;

[0019] The shortfall will be supplied by flat-bed electricity, and the comprehensive investment payback period will be calculated.

[0020] In some technical solutions, the processing without capacity expansion includes:

[0021] Use the surplus capacity of the transformer during off-peak hours to reversely calculate the allowable steam supply and make partial substitution;

[0022] The remaining heating demand is partially supplemented by gas boilers, and the investment payback period is recalculated.

[0023] In some technical solutions, the first enthalpy increment h provided by the heat pump device is increased in the enthalpy distribution, and the following steps are included:

[0024] The heat pump device heats the heat carrier to a first temperature close to the saturation temperature and stores the heat carrier in a pressurized heat-insulating water tank;

[0025] The first temperature range is set according to the heating capacity of the heat pump unit and includes a temperature range of 90°C to 140°C;

[0026] The internal pressure of the pressurized insulated water tank is dynamically adjusted according to the saturation temperature to maintain the liquid state of the heat carrier.

[0027] In some technical solutions, a heat pump device is used to preheat the molten salt of the energy storage device, and the following steps are included:

[0028] During off-peak hours, when the transformer's remaining capacity allows, the heat pump device is used to preheat the molten salt to a temperature close to the maximum heating temperature of the heat pump;

[0029] The molten salt preheating process is completed through a heat exchange pipeline arranged inside the energy storage device, which is used to improve the initial heat storage state of the molten salt.

[0030] In some technical solutions, the energy storage device includes at least one energy storage module, the energy storage module includes an outer cylinder and an inner cylinder, the inner cylinder is arranged inside the outer cylinder, an energy storage medium is arranged between the outer cylinder and the inner cylinder, and the heat exchange pipeline includes a first heat exchange pipeline arranged in the outer cylinder and a second heat exchange pipeline arranged in the inner cylinder;

[0031] The second heat exchange pipeline is also used for preheating the heat storage medium whose temperature is lower than the first temperature.

[0032] In some technical solutions, the energy storage device uses a low melting point molten salt material to achieve deep heat release, and includes the following steps:

[0033] During the heating period, when the energy storage modules of some or all energy storage devices release heat to the set minimum temperature, the heat exchange pipelines are used to continue to provide heat to the cold water or low-level heat source;

[0034] The melting point of the molten salt material is lower than the set minimum temperature.

[0035] According to a second aspect of the present invention, there is further provided an energy storage coupled heat pump heating system, comprising:

[0036] A heat pump device, used to heat a heat carrier to a first temperature and provide a first enthalpy increment h;

[0037] An energy storage device, used to further heat the heat carrier heated to the first temperature by the heat pump device to a second temperature during the heating period, thereby providing a second enthalpy increment (Hh);

[0038] The control module is used to dynamically allocate the first enthalpy increment h and the second enthalpy increment (Hh) according to the heat load demand, so as to realize the coordinated operation of the heat pump device and the energy storage device, and at the same time optimize the investment payback period of the system by combining the electricity price conditions and the system operation efficiency.

[0039] As a preferred solution, the heat pump device comprises:

[0040] A waste heat source heat pump, used to determine whether to start the waste heat source heat pump to use the waste heat resources to provide a part of the first enthalpy increment according to the waste heat resources available in the factory and the operation status during the valley power period and the heating period;

[0041] The air source heat pump is used to dynamically evaluate the availability of the external environmental heat source according to the meteorological temperature conditions, and determine whether to start the air source heat pump to supplement the first enthalpy increment when the waste heat is insufficient or unavailable.

[0042] As a preferred solution, the control module supports comparing the payback period of a single molten salt heating solution with that of an energy storage coupled heat pump heating solution based on the user's expected payback period, and dynamically adjusts the enthalpy distribution ratio h:(Hh) to optimize the system design solution.

[0043] The present invention adopts the above technical solution to have at least the following beneficial effects:

[0044] 1. The present invention dynamically compares the payback period of the single molten salt heating scheme and the energy storage coupled heat pump heating scheme, and selects the optimal scheme in combination with the target payback period set by the user, thereby optimizing the system economy and ensuring the balance between the initial investment and the operating cost. The energy storage coupled heat pump scheme satisfies the user's heating needs by reasonably allocating the enthalpy ratio h:(Hh), significantly reducing the volume and initial investment of the molten salt heat storage module, reducing the system's operating cost and significantly shortening the payback period.

[0045] 2. The present invention monitors the transformer capacity during off-peak hours in real time, and the system gives priority to using low-cost off-peak electricity resources to operate heat pumps and energy storage devices. For scenarios where the transformer capacity is insufficient, the present invention flexibly responds by either expanding or not expanding the capacity. The non-expansion method includes partial replacement or flat-power energy replenishment solutions, which ensures heating demand while further optimizing operating economy. The expansion plan includes the transformer expansion cost into the initial investment, while the non-expansion plan dynamically adjusts the operating status, reversely infers the gas supply according to the transformer capacity, and recalculates the investment payback period.

[0046] 3. The present invention dynamically adjusts the operating status of the heat pump device and the energy storage device, combines the waste heat resources, meteorological conditions and electricity price differences in the plant area, and realizes the coordinated optimization of the efficient operation of the heat pump and the energy storage module, thereby improving the overall energy efficiency of the system. Through the flexible operation mode of the waste heat source heat pump and the air source heat pump, the available heat source resources inside and outside the plant area are fully utilized to improve the system operation efficiency and reduce the operation energy consumption.

[0047] 4. The present invention further improves the heating ratio of the heat pump device by optimizing the enthalpy distribution ratio. The liquid state of high-temperature water is maintained by a pressurized insulated water tank, which reduces the heat release enthalpy increment required by the energy storage device and improves the coefficient of performance (COP) of the heat pump. In addition, combined with the operation mode of the supercritical carbon dioxide heat pump, the system can operate in a higher temperature range, further improving the heating efficiency.

[0048] 5. The present invention uses low-melting-point molten salt materials to enable the heat storage module to achieve deep heat release. Through multi-stage heat exchange, the molten salt module can release heat to a temperature close to the melting point, and further preheat the cold water or provide low-level heat source heat, significantly improving the heat utilization efficiency of the energy storage device. Combined with the preheating operation of the molten salt module by the heat pump device, the initial temperature of the molten salt can also be increased, reducing the electrical energy required for subsequent heating.

[0049] 6. The present invention supports steam heating and ordinary hot water heating scenarios. Through the modular design of the heat storage device, the heating capacity can be flexibly adjusted to meet the needs of various industrial and commercial scenarios. The parallel or series operation of the heat storage module further improves the flexibility and load adaptability of the system.

[0050] 7. The present invention gives priority to using valley electricity resources, and combines waste heat resources and renewable energy to significantly reduce operating costs and carbon emissions. By reducing the proportion of traditional gas boilers, the present invention further reduces the total carbon emissions, meeting energy conservation, emission reduction and environmental protection requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings and their marks required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0052] Figure 1 This is a schematic structural diagram of an energy storage coupled heat pump steam heating system according to an embodiment of the present invention;

[0053] Figure 2 This is a schematic structural diagram of an energy storage module according to an embodiment of the present invention;

[0054] Figure 3 for Figure 2 A schematic diagram of the structure of the outer cylinder of the central energy storage module and its first heat exchange pipeline;

[0055] Figure 4 This is a flow chart of an energy storage coupled heat pump steam heating method according to an embodiment of the present invention;

[0056] Figure 5A flowchart of a common charging and discharging heat cycle of an energy storage module according to an embodiment of the present invention;

[0057] Figure 6 This is a flow chart of an energy storage coupled heat pump steam heating method according to an embodiment of the present invention;

[0058] Figure 7 A flow chart of a steam heating process according to an embodiment of the present invention;

[0059] Figure 8 A flow chart of a charge and discharge heat cycle of a deep heat release energy storage module according to an embodiment of the present invention;

[0060] Fig. 9 This is a flow chart of a method for configuring an energy storage coupled heat pump heating system according to an embodiment of the present invention.

[0061] The meanings of the symbols in the figure are as follows:

[0062] 11—raw water tank, 12—water treatment device, 13—pure water tank, 20—heat pump device, 30—water storage device, 41—recirculation branch, 42—cooling water branch, 43—drain pipe, 44—steam pipe, 50—energy storage module, 51—electric heater, 52—first heat exchange pipe, 53—second heat exchange pipe, 60—steam cylinder, 70—desuperheater, 81—mechanical safety valve, 82—overpressure relief valve. DETAILED DESCRIPTION

[0063] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the specific implementation methods of the present invention will be described below with reference to the accompanying drawings. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings and other implementation methods can be obtained based on these drawings without creative work.

[0064] In order to simplify the drawings, only the parts related to the invention 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".

[0065] 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.

[0066] 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 it can be indirectly connected 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 the present invention can be understood according to specific circumstances.

[0067] 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.

[0068] It should be pointed out that the energy storage coupled heat pump heating system of the present application can be used to supply steam or for ordinary heating, and is therefore not limited to the steam heating system described below.

[0069] like Figure 1 , shows an energy storage coupled heat pump steam heating system of an embodiment of the present invention, comprising a heat pump device 20, a water storage device 30, an energy storage device, and a variety of pipelines and control components connected thereto. The heat pump device 20 and the energy storage device achieve efficient energy transfer and graded utilization through the water storage device 30. Specifically, the heat pump device 20 is used to heat water to a first temperature during the valley power period, the first temperature being a high-temperature water temperature close to the saturation temperature, and transport the high-temperature water to the water storage device 30; the water storage device 30 is responsible for heat preservation and storage of the high-temperature water heated to the first temperature by the heat pump device 20; the energy storage device further heats the high-temperature water to a second temperature to generate a first water vapor to be transported to the steam utilization system.

[0070] In the specific implementation, refer to Figure 2 and Figure 3 The energy storage device includes at least one energy storage module 50, and each energy storage module 50 adopts a double-layer structure of an outer tube and an inner tube. A heat storage medium (such as molten salt) is filled between the outer tube and the inner tube, and a first heat exchange pipeline 52 and a second heat exchange pipeline 53 are respectively arranged on the inner wall of the outer tube and the outer wall of the inner tube. The first heat exchange pipeline 52 is used for heat transfer of high-temperature water, and the water can be further heated to the first water vapor of the second temperature; the second heat exchange pipeline 53 is used to achieve deep heat release of the heat storage medium, and is preheated by the heat pump device 20 during the valley power period. Preferably, the first heat exchange pipeline 52 is a heat exchange coil welded to the inner wall of the outer tube, and the second heat exchange pipeline 53 is a heat exchange coil welded to the outer wall of the inner tube, and the heat exchange coil can be a vertical serpentine coil. The above design not only optimizes the heat utilization efficiency of the heat storage medium, but also improves the overall energy efficiency of the energy storage device through the double-layer heat exchange structure.

[0071] Furthermore, in order to enhance the applicability and flexibility of the energy storage device, multiple inner cylinders in this embodiment can be provided, and different structural configurations can be adopted. For example, multiple inner cylinders can be stacked on each other to form a concentric circle arrangement, or multiple single inner cylinders can be independently provided. The internal structural design of the inner cylinder supports a variety of implementation methods: it can be filled with molten salt to increase the energy storage capacity, or it can be filled with solid heat exchange materials (such as graphite blocks) to enhance thermal conductivity, and it can even be designed as a hollow structure for direct heat exchange under specific conditions. In addition, the type of molten salt between the inner cylinder and the outer cylinder can be the same, or different types of molten salts can be selected according to specific working conditions, such as the inner cylinder filled with low melting point molten salt and the outer cylinder filled with high melting point molten salt to achieve a wider temperature operating range.

[0072] In order to adapt to large-scale production and subsequent expansion needs, the molten salt energy storage module in this embodiment adopts a modular design, the energy storage capacity of a single module is Q0, and the upper limit of heat release power is P0. The modular design allows the energy storage device to flexibly adjust the number of modules according to specific steam demand, and supports parallel or series operation mode to meet different working conditions.

[0073] In the specific design, in order to ensure that the maintenance of a single module will not affect the overall heating supply, the number of modules must meet the following conditions: the daily steam demand on the user side is Q, and the hourly steam power is P. If n is 2, then at least 2 modules are needed; if n is ≥ 2, then directly take At the same time, the energy storage capacity of a single module is calculated as Q0=90%×Q / n, to ensure that the energy storage module 50 has a certain energy storage margin while meeting the steam supply demand. In a more specific embodiment, the selected power of the heat pump device 20 is 10% of the total steam demand on the user side, that is, 10%*Q / t, where t is the number of operating hours of the heat pump device 20. Through reasonable selection, the heat pump device 20 can operate efficiently during the valley power period, prepare high-temperature water close to the saturation temperature and supply it to the energy storage module 50, effectively reducing the overall energy consumption of the system.

[0074] In the scenario of high steam demand, the energy storage module 50 can be switched to the parallel operation mode, and each module releases heat independently to form a multi-channel steam generation path to meet the rapid steam supply demand and significantly improve the steam supply response speed; in the scenario of low steam demand, the energy storage module 50 switches to the series operation mode, and the low-temperature molten salt that has released part of the heat is used to preheat other modules to maximize the utilization of the heat storage medium, thereby optimizing energy efficiency. In addition, in order to enhance operational flexibility, in the series mode, the preheating flow between the modules can be dynamically adjusted to optimize the heat distribution.

[0075] This embodiment specifically uses three parallel molten salt energy storage modules, and its operating temperature range is 180°C to 400°C (fifth temperature to fourth temperature), which is suitable for large-scale industrial steam demand. However, the configuration of the energy storage module 50 is not limited to this. In other embodiments, solid energy storage, phase change energy storage or thermochemical energy storage modules may be used as required. Different energy storage modules 50 may be the same or different, and the operating temperature may be set uniformly or in sections. For example, in a system requiring multi-stage heating, a molten salt energy storage module (high temperature section), a phase change energy storage module (medium temperature section) and a solid energy storage module (low temperature section) may be configured in combination to meet complex process requirements.

[0076] Preferably, the molten salt can be a low melting point mixed molten salt (melting point below 100°C) to reduce the system startup temperature and enhance the deep heat release capacity of the energy storage module 50. In addition, the heat storage medium can also be a high thermal conductivity solid material (such as graphite or metal aluminum) to improve the heat transfer efficiency and adapt to the high heat flux density requirements under special operating conditions. For low temperature applications, phase change energy storage materials (such as sodium hydroxide) can provide higher energy storage density while reducing the material volume and improving the compactness of the system.

[0077] In a specific embodiment, the energy storage module 50 also includes an electric heater 51, which is configured to be directly inserted from the top of the energy storage module 50, and the distance from the bottom of the module is controlled between 100 and 200 mm to balance the heating effect and the temperature control requirements of the module base. The number of electric heaters 51 is generally 5 to 6, one of which is a full-segment heater, which is used to melt solid molten salt. Its immersed part can heat up in the whole section, and the power is adjusted by a thyristor. The remaining electric heaters 51 are 2 / 3-segment heating, which only heats the lower 2 / 3 of the molten salt, and the power is not adjustable. By reasonably configuring the heating section and combining the upper hot and lower cold temperature stratification characteristics in the module, the phenomenon of overheating of the upper molten salt and insufficient heating of the lower molten salt is effectively avoided, and the uniformity of molten salt heating and the stability of system operation are improved.

[0078] When further optimized, the heat pump device 20 adopts a transcritical carbon dioxide cycle design, and realizes heat conversion from a low-temperature heat source to a high-temperature heat carrier through an efficient transcritical cycle. This design enables the outlet temperature range of the heat pump to be accurately controlled within a range close to the saturation temperature (for example, 90 to 98°C), providing high-temperature water at the optimal operating temperature for the energy storage device, significantly improving the heating efficiency of the energy storage device. The heat pump device 20 can be selected according to different heat source conditions, such as air source heat pumps, water source heat pumps, ground source heat pumps, or waste heat source heat pumps. The specific configuration can be optimized based on environmental conditions and steam demand. Furthermore, the heat pump device 20 can adopt a cascade heating design to meet higher temperature requirements.

[0079] When further optimized, the water storage device 30 is connected between the heat pump device 20 and the energy storage device, and has sealing and pressurizing functions, which is used to maintain the liquid state of high-temperature water and avoid phase change heat loss. To further optimize the system performance, when the heating capacity of the heat pump device 20 can reach 150°C, the water storage device 30 can adopt a pressurized insulated water tank design, and maintain its internal pressure at about 0.6MPa to ensure that the saturation temperature of the water reaches about 158°C. Under this pressure condition, when the heat pump device 20 heats the water to the first temperature (150°C), the water remains in liquid state and is slightly lower than the saturation temperature. This design makes full use of the heating capacity and high energy efficiency characteristics of the heat pump.

[0080] Furthermore, when a heat pump device 20 with a higher heating capacity is used (for example, heating to 180°C or higher), the internal pressure of the water storage device 30 can be increased accordingly to match the saturation temperature of the water. For example, when the target heating temperature is 180°C, the internal pressure of the water storage device 30 can be increased to about 1.0MPa, so that the saturation temperature of the water exceeds the target temperature, ensuring the stability of the liquid state. By dynamically adjusting the pressure setting of the water storage device 30, it is possible to flexibly adapt to the heating capacity and working conditions of different models of heat pumps, further improving the applicability and energy efficiency of the system.

[0081] The high-pressure insulation design of the water storage device 30 also has the following advantages: on the one hand, by maintaining a high internal pressure, the heat loss of high-temperature water is effectively reduced, ensuring its efficient transmission to the energy storage device; on the other hand, liquid high-temperature water under high pressure conditions can significantly reduce the time delay of steam supply and improve the response speed of the entire system. In addition, the water storage device 30 is combined with high-efficiency insulation materials to further reduce the heat loss during long-term storage, significantly improving the overall operating efficiency of the system.

[0082] Therefore, by combining the heating capacity of the heat pump with the design of the pressurized insulated water tank, this solution fully utilizes the high-efficiency heating characteristics of the heat pump device 20. At the same time, through the dynamic pressure regulation of the water storage device 30, it adapts to various working conditions and provides reliable guarantee for efficient and stable steam heating.

[0083] In addition, the present invention also provides a specific example to analyze the change of the overall energy efficiency of the system:

[0084] Assuming that the system heat source temperature is 10℃, the output steam temperature is 180℃, and the insulated water tank works under different temperature conditions, analyze the changes in the overall COP of the system. When the insulated water tank temperature is 95℃, the heat pump heats the water from 10℃ to 95℃, and the required heat is Q 热泵 =1×4.2×(95-10)=357kJ / kg. Assuming the COP of the heat pump is 3.0, the input power of the heat pump is W 热泵 =Q 热泵÷COP=357÷3.0=119kJ / kg. The energy storage device needs to heat water from 95℃ to 180℃, and the required heat is Q 储能 =1×4.2×(180-95)=357kJ / kg. Assume that the efficiency of the energy storage device is 90% and the energy storage loss is L 储能 =Q 储能 ×0.1=35.7kJ / kg. The total input power of the system is W 总＝ W 热泵 +L 储能 =119+35.7=154.7kJ / kg, the total heat output is Q 总输出 =Q 热泵 +Q 储能 =357+357=714 kJ / kg. At this time, the total COP of the system is COP 系统 =Q 总输出 ÷W 总 =714÷154.7≈0.97.

[0085] When the temperature of the insulated water tank rises to 150℃, the heat pump needs to heat the water from 10℃ to 150℃, and the required heat is Q 热泵 =1×4.2×(150-10)=588kJ / kg. Assuming the heat pump COP drops to 2.2, the heat pump input power is W 热泵 =Q 热泵 ÷COP=588÷2.2=267.3kJ / kg. The energy storage device only needs to heat water from 150℃ to 180℃, and the required heat is Q 储能 =1×4.2×(180-150)=126kJ / kg, energy storage loss is L 储能 =Q 储能 ×0.1=12.6kJ / kg. The total input power of the system is W 总 =W 热泵 +L 储能 =267.3+12.6=279.9kJ / kg, the total heat output is Q 总输出 =Q 热泵 +Q 储能 =588+126=714 kJ / kg. At this time, the total COP of the system is COP 系统 =Q 总输出 ÷W 总 =714÷279.9≈1.02.

[0086] From the results, it can be seen that although the heat pump COP dropped from 3.0 to 2.2 due to the increase in outlet temperature, the total system COP increased from 0.97 to 1.02 due to the significant reduction in the burden of the energy storage device, indicating that increasing the temperature of the insulation water tank can optimize the overall efficiency of the system within a certain range. In practical applications, it is necessary to further simulate and optimize the operating temperature of the insulation water tank according to specific system parameters to achieve optimal performance.

[0087] In a further optimized embodiment, the energy storage coupled heat pump steam heating system includes a variety of pipelines and control components for achieving efficient heat transfer and flexible regulation of system operation. The pipelines and control components mainly include a first water supply pipeline, a recirculation branch 41, a desuperheating water branch 42, a second water supply pipeline, a preheating circuit, a branch pipe regulating valve group and an electric valve matched therewith, a main pipe regulating valve group and a desuperheater 70, etc.

[0088] The first water supply pipeline connects the water storage device 30 and the energy storage module 50, and is used to transport high-temperature water to the heat exchange pipeline of the energy storage module 50. Two groups of water supply pumps are arranged in the first water supply pipeline, one for use and one for backup, and the continuity and reliability of water supply are ensured by an automatic switching mechanism. The main pipe regulating valve group is connected to the water supply pump group to adjust the flow rate of high-temperature water delivered to the energy storage module 50 to ensure that different steam load requirements are met. If the system includes multiple energy storage modules 50, the main pipe regulating valve group is connected to each module through a branch pipe regulating valve group. The branch pipe regulating valve group is used to accurately adjust the flow rate of high-temperature water entering each energy storage module 50 to ensure that each module is evenly fed with water during operation. In addition, an electric valve is arranged between each branch pipe regulating valve group and the energy storage module 50, which is used to shut down when a specific module stops running or is under maintenance.

[0089] A recirculation branch 41 is drawn from between the main pipe regulating valve group and the energy storage module 50 and connected to the water storage device 30 to realize the reflux of high-temperature water when the system is running. The recirculation branch 41 can be opened through bypass regulation when the system pressure rises rapidly, and part of the feed water is returned to the water storage device 30, thereby reducing the amount of water entering the energy storage module 50, controlling the pressure fluctuation of the system, and avoiding overpressure operation of the system.

[0090] A cooling water branch 42 is led out from between the water supply pump group and the main pipe regulating valve group in the first water supply pipeline and connected to the cooling water input port of the desuperheater 70. The cooling water transported by the branch is mixed with the high-temperature steam in the desuperheater 70 and then output to the steam main pipe on the user side to adjust the steam temperature to the third temperature required by the user. The connection method of the cooling water branch 42 ensures that the inlet pressure of the cooling water pipeline is not affected by the action of the main pipe regulating valve, ensuring that the steam temperature on the user side does not exceed the limit under any working conditions.

[0091] The second water supply pipeline connects the heat pump device 20 and the energy storage module 50, and is used to directly transport the high-temperature water generated by the heat pump device 20 to the heat exchange pipeline of the energy storage module 50. The heat pump device 20 is used to directly supply water to the energy storage device, or to supply water to the energy storage device simultaneously with the water storage device 30. It is used when the steam demand is small, for example, when the water supply flow of the heat pump device 20 meets the steam demand flow, water can be directly supplied from the heat pump device 20 to the energy storage device; or it can be used for emergency.

[0092] The desuperheater 70 is connected to the pressure stabilizing device through the steam input port, and the pressure stabilizing device is connected to the energy storage module 50, so that the energy storage module 50 supplies the first water vapor to the pressure stabilizing device, and the desuperheating water branch 42 is connected to the desuperheating water input port of the desuperheater 70. The pressure stabilizing device is preferably a steam cylinder 60, and the steam output of the energy storage module 50 is collected and merged into one path through the steam cylinder 60 and then enters the desuperheater 70, where it is fully mixed with the desuperheating water and outputs a steam temperature that meets the user's needs. The design of the desuperheater 70 can flexibly adjust the steam temperature to adapt to different user-side process requirements, ensuring the accuracy and stability of steam supply.

[0093] The preheating circuit is used to preheat the heat storage medium in the energy storage module 50 by using the heat pump device 20 during the off-peak period. The preheating circuit includes a third water supply pipeline and a preheating return water pipeline, which are respectively connected between the heat pump device 20 and the energy storage module 50 to form a closed loop to achieve efficient heating of the heat storage medium below the first temperature. Specifically, the third water supply pipeline is connected to the outlet end of the heat pump device 20, and is used to transport the high-temperature water heated by the heat pump to the heat exchange pipeline inside the energy storage module 50, and use the sensible heat of the high-temperature water to heat the heat storage medium; the preheating return water pipeline is connected to the outlet end of the heat exchange pipeline inside the energy storage module 50, and is used to return the low-temperature water after heat exchange to the inlet end of the heat pump device 20 for circulation heating. Through this preheating circuit, the heat pump can achieve graded heating at the temperature of the low-temperature heat storage medium, so that it gradually approaches the first temperature, providing a more efficient thermal state for the subsequent high-temperature water preparation and steam generation process.

[0094] Furthermore, the heat exchange pipeline of the energy storage module 50 is designed to be compatible with the operating mode of the preheating circuit. The third water supply pipeline and the preheating return water pipeline in the preheating circuit are both connected to the heat exchange pipeline inlet and outlet of the energy storage module 50, so that the third water supply pipeline, the heat exchange pipeline and the preheating return water pipeline together constitute an efficient preheating circulation loop. In addition, in order to further improve the preheating efficiency of the energy storage module 50, an independent preheating pipeline may be additionally provided inside the energy storage module 50. The third water supply pipeline and the preheating return water pipeline are respectively connected to the independent preheating pipeline to form a more specialized preheating circuit for specially handling the low-temperature preheating requirements of the heat storage medium under specific working conditions. Specifically, the preheating circuit is connected to the first heat exchange pipeline 52 and / or the second heat exchange pipeline 53, and preferably the second heat exchange pipeline 53, and the preheating pipeline is arranged on the inner cylinder wall of the energy storage module 50, preferably the outer wall of the inner cylinder is welded.

[0095] In this embodiment, the preheating circuit not only uses the heat pump to preheat the heat storage medium during the off-peak period to improve the standby efficiency of the energy storage module 50, but also significantly shortens the startup time of the system and reduces the operating load of the traditional high-energy consumption heater during the startup phase.

[0096] In a further optimized embodiment, the energy storage coupled heat pump steam heating system includes a deionized water supply device, a sewage pipeline 43, and a multi-stage pressure protection and pressure relief component to ensure the stability and safety of the system operation.

[0097] The deionized water supply device includes a raw water tank 11, a water treatment device 12, a pure water tank 13 and a deionized water supply pipeline connected in sequence. In order to improve the reliability of the system operation, a tap water pipe bypass is set in front of the inlet of the pure water tank 13. When the water treatment device 12 cannot work normally, the tap water can directly enter the pure water tank 13 through the bypass as a temporary water source. Specifically, the raw water is taken out from the tap water pipeline in the factory area and first enters the raw water tank 11. The raw water tank 11 serves as a buffer device and can store about 3 to 6 hours of water consumption to cope with instantaneous water demand fluctuations. The raw water is transported to the water treatment device 12 through the raw water pump for softening and desalination. The quality of the treated deionized water should meet the through-flow boiler water quality standard in GB / T1576 "Industrial Boiler Water Quality". It is then temporarily stored in the pure water tank 13. The pure water tank 13 has a storage capacity of about 3 hours of water consumption, ensuring the continuous water supply capacity of the system when the water treatment device 12 is overhauled or shut down.

[0098] Two groups of deionized water pumps are arranged on the deionized water supply pipeline, one for use and one for standby, and the continuous supply of deionized water is ensured through the automatic switching function. The deionized water passing through the deionized water pump enters the heat pump device 20 through the regulating valve.

[0099] In other embodiments, the deionized water supply device may also supply water to the energy storage module 50 and the desuperheated water inlet respectively according to demand.

[0100] The water supply port of the energy storage module 50 is connected to the drain pipe 43, which is used to discharge the residual working fluid in the energy storage module 50 when the system is shut down or in an emergency. A drain valve is arranged near the water supply port of the drain pipe 43, which may include an electric shut-off valve and a manual shut-off valve. During normal operation, the drain valve remains closed. When the system is shut down or the system is over-pressurized, the drain valve is opened, and the residual water working fluid is pressed into the drain well by the residual pressure in the energy storage module 50, ensuring that there is no retained working fluid in the system, thereby improving the operation safety.

[0101] The steam pipeline 44 connects the energy storage module 50 and the pressure stabilizing device for conveying steam. A mechanical safety valve 81 is installed on the steam pipeline 44. When the steam pressure exceeds the set safety threshold, the mechanical safety valve 81 automatically trips to release excess steam to prevent system overpressure. After the steam is output, it is merged into the sub-cylinder 60 and connected to the desuperheater 70 through the steam main pipe. An overpressure relief valve 82 is set on the steam main pipe. When the steam pressure exceeds the second warning value, the overpressure relief valve 82 automatically opens to discharge the excess steam to a safe area.

[0102] In order to ensure the safety of the system under different operating conditions, this system is equipped with four pressure protection measures: the first warning: when the steam pressure exceeds the set threshold, the water supply main pipe regulating valve automatically adjusts the flow according to the pressure signal to control the amount of high-temperature water entering the energy storage module 50 to balance the system pressure; the second warning: when the pressure continues to rise, the overpressure relief valve 82 opens to discharge excess steam to a safe area; the third warning: if the pressure further rises to the emergency shutdown threshold, the system enters an emergency shutdown state, and the drain valve opens at the same time to quickly discharge all working fluids to the drain well to quickly reduce the system pressure; the fourth warning: in extreme overpressure conditions, the mechanical safety valve 81 automatically trips to release steam to ensure the safe operation of the system and equipment. Through the above-mentioned multi-level pressure protection design and the rapid response capability of the drain pipeline 43, the system can quickly take countermeasures in the event of sudden pressure fluctuations, significantly reducing the risk of overpressure and improving the safety and stability of operation.

[0103] In a further embodiment, the energy storage module 50 is equipped with an auxiliary heater and an emergency heating module to enhance the operational flexibility and reliability of the system. The auxiliary heater directly heats the fluid in the heat exchange pipeline, and is mainly used for rapid temperature rise during the startup phase or heat supplement during low-load operation. The emergency heating module includes an emergency heating pipeline, which can be connected in series or in parallel with the heat exchange pipeline of the energy storage module 50 to provide supplementary heating when the heat release power of the energy storage module 50 is insufficient or some modules are under maintenance. Through the above configuration, the system can achieve continuous and stable heat supply during startup, load peak or special operating conditions, significantly improving operational efficiency and safety.

[0104] In one embodiment of the present invention, the energy storage coupled heat pump heating system includes a control module to realize the coordinated operation, dynamic regulation and energy efficiency optimization of the heat pump device and the energy storage device; of course, it can be used for the implementation of the control components in the aforementioned energy storage coupled heat pump steam heating system, and the implementation of the following energy storage coupled heat pump steam heating method.

[0105] Specifically, the control module is used to dynamically allocate the first enthalpy increment h and the second enthalpy increment (Hh) according to the heat load demand, so as to realize the coordinated operation of the heat pump device and the energy storage device, and at the same time optimize the system's investment payback period by combining the electricity price conditions and the system operation efficiency.

[0106] Furthermore, the control module supports comparison of the payback period of a single molten salt heating scheme and a storage-coupled heat pump heating scheme based on the user's expected payback period, and dynamically adjusts the enthalpy distribution ratio h:(Hh) to optimize the system design scheme.

[0107] In another embodiment of the present invention, Fig. 9 , showing a configuration method of an energy storage coupled heat pump heating system, comprising the following steps:

[0108] S310, quantify the heating demand. For example, when the heating demand is steam demand, steam load forecasting is performed based on the factory's historical data, including steam demand, temperature and pressure parameters. A factory in this embodiment requires high-temperature steam at 180°C, 0.6MPa, and an average of 13 tons / day, which is required for 330 days per year, and the demand occurs during flat power periods. The specific enthalpy of this steam is 2805kJ / kg, and the specific enthalpy of normal temperature water is 83kJ / kg. The energy required to heat the normal temperature water to the steam is (2805-83)*13 / 3.6=9829kWh.

[0109] S320, calculate the payback period of the single molten salt solution. Specifically, calculate the payback period when the single molten salt solution replaces the traditional boiler solution. Since molten salt energy storage can utilize low-priced valley electricity, it can save operating costs. Payback period Pt2 = CM / S1, where Pt2 is the payback period of the single molten salt solution, CM is the initial investment amount of the molten salt energy storage system, and S1 is the annual electricity cost savings. The valley electricity price is 0.37 yuan / kWh, the flat electricity price is 0.76 yuan / kWh, and the average valley electricity surplus capacity is 1500kW. The factory originally used natural gas boilers, and the steam cost was 467 yuan / ton. The single molten salt solution requires 9829 / 0.9 = 10920kWh of electricity per day. The valley electricity time is 8 hours, and the valley electricity surplus is 1500*8 = 12000kWh. Therefore, the capacity is sufficient. S1 = (467*13-10920*0.37)*330 = 670,000 yuan. The investment amount is 5.2 million yuan, and the investment payback period = 520 / 67 = 7.76 years.

[0110] S330, calculate the payback period of the molten salt coupled heat pump heating system. Specifically, H is allocated to the heat pump and molten salt heat storage according to the ratio of h:(Hh). Among them, h is the enthalpy value increased by the heat pump heating, H is the enthalpy value per unit steam required by the user, and Hh is the enthalpy value provided by the molten salt heat release. The process of determining h is as follows: according to the waste heat resources available in the factory (including valley power period and heating period), determine whether to turn on the waste heat source heat pump for heat pump heating; at the same time, according to the meteorological temperature conditions, determine whether to turn on the air source heat pump for heat pump heating; according to the heating conditions of the waste heat source heat pump and the air source heat pump, determine h and its COP. Then convert the heat data into electricity demand. The amount of electricity required by the heat pump is: E1 = Qxh / cop; the amount of electricity required by the molten salt heat storage is E2 = Qx(Hh) / η. Finally, the investment payback period of the molten salt coupled heat pump heating system is calculated similarly: Pt1 = CH / S2; where CH is the initial investment of the molten salt coupled heat pump heating system, and S2 is the annual electricity cost savings.

[0111] The energy provided by the heat pump is 1145kWh, and the heat provided by the molten salt heat storage is 9829-1145=8684kWh; the COP of the heat pump is 3, so the power consumption of the heat pump is 1145 / 3=382kWh; the molten salt heat storage efficiency is 0.9, so the power consumption of the molten salt heat storage is 8684 / 0.9=9649kWh, the molten salt charging power is 1200kWh, the heat pump power is 48kW, the daily electricity bill is 9649*0.37+382*0.37=3711, the annual cost savings = 330*(467*13-3711) = 778,800 yuan, the total investment is 5.8 million yuan, and the investment recovery period = 580 / 77.88 = 7.45 years.

[0112] S340, comparing schemes Pt2 and Pt1, and the user's expected investment payback period Pc = 10 years after considering carbon emission costs, decides to adopt the molten salt thermal storage coupled heat pump scheme.

[0113] Furthermore, in steps S320 and S330, whether the transformer capacity is sufficient is considered respectively.

[0114] In step S320, when the transformer capacity is sufficient, the calculation can be performed according to the above method; when the transformer capacity is insufficient, it is necessary to calculate the expansion and non-expansion cases separately. When expanding, the initial investment CM'=Qxc1+CK, that is, the molten salt investment plus the expansion fee. At this time, the investment payback period Pt2'=CM' / S1. When not expanding, the allowable gas supply Q' of the molten salt module is reversed according to the transformer surplus capacity P, and the molten salt module is used to partially replace the original gas supply, and the investment payback period is calculated.

[0115] After the calculation is completed, compare the investment payback period of expansion and non-expansion, and choose the shorter option.

[0116] In step S330, when the transformer capacity is sufficient, the above calculation is performed. When the transformer capacity is insufficient, the expansion and non-expansion cases are calculated respectively. When the capacity is expanded, the initial investment CH'=E2xηxc1+P1xc2+CK, and the investment recovery period Pt1'=CH' / S2. When the capacity is not expanded, the allowable gas supply Q' is reversed according to the transformer surplus capacity P, partial replacement is performed, and the investment recovery period is calculated.

[0117] After the calculation is completed, compare the investment payback period of expansion and non-expansion, and choose the shorter option.

[0118] Furthermore, in steps S320 and S330, whether the transformer capacity is sufficient is considered respectively.

[0119] In step S320, when the transformer capacity is sufficient, the above calculation is sufficient; when the transformer capacity is insufficient, it is necessary to calculate the expansion and non-expansion cases separately. When expanding, the initial investment CM'=Qxc1+CK, that is, the molten salt investment plus the expansion fee. At this time, the investment payback period Pt2'=CM' / S1. When not expanding, the insufficient part uses the electricity of the flat power, and the investment payback period is calculated.

[0120] After the calculation is completed, compare the investment payback period of expansion and non-expansion, and choose the shorter option.

[0121] In step S330, when the transformer capacity is sufficient, the above calculation is performed. When the transformer capacity is insufficient, the expansion and non-expansion cases are calculated respectively. When the capacity is expanded, the initial investment CH'=E2xηx c1+P1xc2+CK, and the investment payback period Pt1'=CH' / S2. When the capacity is not expanded, the insufficient part uses the electric energy of the flat power, and the investment payback period is calculated.

[0122] After the calculation is completed, compare the investment payback period of expansion and non-expansion, and choose the shorter option.

[0123] For example, when the surplus capacity of the valley power transformer in the above scheme is 1200kW, 1200*8=9600KWh<10920kWh. The project does not have the conditions for capacity expansion, so it will be supplemented during the flat power period. The daily electricity fee is 1200*8*0.37+(10920-1200*8)*0.76=4556 yuan, and the annual cost savings are 330*(467*13-4556)=500,000 yuan. The total investment is still 5.2 million yuan, and the static investment recovery period is 520 / 50=10.4 years, which does not meet the expected investment recovery period of 10 years.

[0124] When the coupled heat pump solution is adopted, the heat pump provides 1145kWh of energy, and the molten salt heat storage provides 9829-1145=8684kWh of heat; the heat pump COP is 3, so the heat pump consumes 1145 / 3=382kWh of electricity; the molten salt heat storage efficiency is 0.9, so the molten salt heat storage consumes 8684 / 0.9=9649kWh of electricity, the molten salt valley electricity charging is 9600kWh, the flat electricity charging power is 49kWh, and the heat pump uses flat electricity. The daily electricity bill is 9600*0.37+(382+49)*0.76=3880, and the annual cost savings = 330*(467*13-3880) = 723,000 yuan, the total investment is 5.8 million yuan, and the investment recovery period = 580 / 72.30 = 8.02 years.

[0125] Therefore, a coupled heat pump solution is adopted.

[0126] The present invention also provides an energy storage coupled heat pump steam heating method, which combines the hierarchical cooperation of the heat pump device, the water storage device and the energy storage module, and utilizes the efficient heating capacity of the heat pump device during the off-peak period to heat the water to high-temperature water of a first temperature, and further heats the water to a first water vapor of a second temperature through the energy storage module to meet the steam demand on the user side. This method realizes the efficient use of energy and optimizes the operating economy and flexibility of the system. It should be pointed out that the following embodiments of the energy storage coupled heat pump steam heating method are suitable for operation in the aforementioned system structure, but are not limited to the aforementioned system structure.

[0127] According to a specific embodiment of the present invention, Figure 4-7 In this embodiment, the energy storage coupled heat pump steam heating method includes the following steps:

[0128] S1. The heat pump device 20 is used to heat the desalted water to a first temperature (close to the saturation temperature) of high temperature water, and the desalted water is stored in the water storage device 30 in a heat-insulated manner.

[0129] S2. During the steam supply period, the high-temperature water in the water storage device 30 is transported to the energy storage module 50 through the first water supply pipeline, and is further heated to a second temperature by the molten salt storage tank to generate first water vapor.

[0130] Furthermore, the first temperature is set according to the heating capacity of the heat pump device 20. When the heat pump device 20 has a higher heating capacity (for example, a transcritical carbon dioxide heat pump), the water can be heated to a temperature higher than 100°C. At this time, the present embodiment uses a pressurized insulated water tank to maintain the liquid state of the high-temperature water by setting a specific pressure value. At the same time, the first water supply pipeline is also matched with pressure regulation, and is used as a pressure pipeline to transport the high-temperature water between the heat pump device 20 and the water storage device 30.

[0131] Preferably, the first temperature is lower than the first temperature difference corresponding to the saturation temperature, and the range of the first temperature difference is 2 to 10°C, preferably 4 to 6°C. This can effectively avoid the vaporization phenomenon that may occur when the liquid high-temperature water approaches or exceeds the saturation temperature during the heating process, and ensure the stable liquid state of the high-temperature water in the water storage device 30 and the delivery pipeline. This not only improves the heating efficiency of the heat pump device 20 and reduces energy consumption, but also reduces heat loss and system fluctuations caused by phase change.

[0132] Furthermore, the method further comprises the following steps:

[0133] S3. Use the desuperheater 70 to mix the first water vapor at the second temperature with the high-temperature water at the first temperature to generate the second water vapor at a third temperature, wherein the third temperature is between the first temperature and the second temperature (e.g., 180-250° C.) to meet the demand of the steam using system for steam at different temperatures.

[0134] This embodiment realizes hierarchical and efficient utilization of heat by organically combining the efficient heating characteristics of the heat pump device 20 and the high-density energy storage characteristics of the energy storage device. This method not only significantly improves the energy efficiency of the system and reduces energy costs, but also optimizes the operating load of the energy storage module 50 and reduces the thermal stress of the molten salt, thereby extending the service life of the equipment, improving the safety and stability of the system operation, and meeting the economy and flexibility of industrial steam demand.

[0135] In another embodiment (operation control of the energy storage device and the heat pump device 20), as Figure 5-7 , including the following specific steps:

[0136] S10, using the historical data and real-time working conditions of the steam use system, predicting the first steam demand in the steam supply period, and determining the corresponding first water vapor enthalpy increment. Based on the prediction results, providing a control basis for the operation of the energy storage device and the heat pump device 20.

[0137] S20. During the valley power period, heat is stored by the energy storage device in an electrically heated manner to heat the heat storage medium (such as molten salt) to a set fourth temperature (such as 400° C.). Preferably, the heating temperature of the heat storage medium is dynamically adjusted according to demand to ensure the economy and effectiveness of heat storage.

[0138] S30, controlling the heat pump device 20 to operate at least part of the time during the off-peak period to prepare the required high-temperature water, and heating the desalted water to a first temperature close to the saturation temperature (eg, 90°C).

[0139] S40, making the sum of the second enthalpy increment provided by the energy storage device releasing heat and the first enthalpy increment provided by the heat pump device 20 heating match the enthalpy increment of the first water vapor corresponding to the first steam demand.

[0140] Furthermore, the operation ratio of the heat pump device 20 during the off-peak period is optimized, and the specific process is as follows:

[0141] S31, obtaining the power supply capacity that can be used for steam generation during the valley power period, and determining the second power consumption required by the energy storage device during the valley power period;

[0142] S32, calculating a first difference between the valley power supply capacity and the second power consumption of the energy storage device:

[0143] If the first difference in electricity is sufficient to complete the preparation of the required total amount of high-temperature water, the heat pump device 20 completes the preparation of all high-temperature water during the valley electricity period;

[0144] If the first difference in electricity is insufficient, the heat pump device 20 uses the first difference in electricity to partially prepare high-temperature water during the off-peak period, and the rest is replenished during the normal period.

[0145] S33, calculating the first power consumption required by the heat pump device 20 to prepare all high-temperature water that meets the steam supply demand during the off-peak period. The first power consumption is a function of the operation time, power and water heating demand of the heat pump device 20, ensuring that the prepared high-temperature water can meet the first temperature demand.

[0146] S34, after deducting the second power consumption of the energy storage device from the power supply capacity during the off-peak period, calculate the remaining power (first difference power). Then calculate the difference between the first difference power and the first power consumption to obtain the second difference power. The second difference power is the remaining power of the system.

[0147] S35. Real-time monitoring of the first difference in electricity and the heating capacity of the heat pump device 20. When the first difference in electricity and the heating capacity of the heat pump device 20 exceed the demand for high-temperature water at the first temperature, the second difference in electricity is used to provide preheating heat for the energy storage device through the heat pump device 20.

[0148] Furthermore, this embodiment also includes the following steps:

[0149] S51. During the steam supply period, the high enthalpy heat provided by the energy storage device is used to further heat the high-temperature water to generate superheated steam at a second temperature for use by the user side.

[0150] S52. During the period of steam demand, when the heat release power of the energy storage device is insufficient (for example, at the end of the steam supply period), the high-temperature water in the heat exchange pipeline is quickly supplemented with heating by the configured auxiliary heater or auxiliary heating module to ensure the continuity and stability of the steam supply.

[0151] S53. During the period of steam demand, after the molten salt storage tank releases heat to the fifth temperature (for example, 200°C), if there is still a demand for steam, high-temperature water is dynamically added to the energy storage device through the heat pump device 20, and combined with the electric heating function of the energy storage module 50, the heat output is further improved; or the heat pump device 20 is used to directly heat to the target temperature to ensure the stability and continuity of the steam supply.

[0152] This embodiment uses the coordinated operation and control of the energy storage device and the heat pump device 20, combined with historical data and load prediction of real-time working conditions, to accurately match the steam supply demand, significantly improving the operating efficiency and flexibility of the system. During the off-peak period, by optimizing the operation strategy of the energy storage device and the heat pump device 20, low-cost electricity is fully utilized to heat the heat storage medium to a set high temperature state and prepare high-temperature water that meets the demand; during the steam supply period, the high enthalpy heat provided by the energy storage device and the dynamic supplement of the heat pump device 20 are used to ensure the continuity and stability of the steam supply.

[0153] This embodiment achieves the optimal allocation of power resources during the off-peak period. After the high-temperature water demand is met, the remaining power is used to preheat the energy storage device, reducing the heating burden during the steam supply period and further improving the system energy efficiency. At the same time, in the late stage of steam supply or load peak scenarios, the auxiliary heating module and the heat pump device 20 are combined with dynamic regulation to effectively avoid steam supply interruption caused by insufficient energy storage capacity.

[0154] In another embodiment (determination of energy storage capacity and heat release power of energy storage device), the following specific steps are included:

[0155] S71. Use historical data and real-time operating conditions to predict the first steam demand and maximum steam demand rate during the steam supply period, which correspond to the total heat demand and instantaneous heating capacity demand of the energy storage device, respectively. According to the steam demand characteristics, calculate the enthalpy increment of heat provided by the heat pump device 20 and the energy storage device, and determine the first ratio of the two. Preferably, the heat pump device 20 operates in the high-efficiency range, mainly providing the first enthalpy increment for preparing high-temperature water; the energy storage device assumes the heat output of high enthalpy value as the second enthalpy increment to meet the high temperature demand for steam generation.

[0156] According to the first ratio, the core parameters of the energy storage device are determined using the following steps:

[0157] S72. Determine the energy storage capacity of the energy storage device in combination with the first steam demand and the first ratio to ensure that it has sufficient heat reserve during the steam supply period. The heat storage medium is preferably molten salt, and the required mass and volume are calculated based on the operating temperature range and specific heat capacity to ensure the economy and effectiveness of heat storage.

[0158] S73. According to the maximum steam demand rate and the first ratio, the heat release power of the energy storage device is designed to match the instantaneous steam load demand. The stability and uniformity of steam output are ensured by optimizing the heat exchange pipeline and branch pipe regulating valve group.

[0159] This embodiment scientifically allocates the heat supply ratio of the heat pump device 20 and the energy storage device by predicting the steam demand and the maximum steam demand rate, and optimizes the design of the energy storage capacity and heat release power. The heat pump device 20 operates in a high energy efficiency range to prepare high-temperature water; the energy storage device provides high enthalpy heat to meet instantaneous load requirements. This method realizes the hierarchical utilization and precise matching of thermal energy, reduces operating costs, enhances the system's adaptability to load fluctuations, and provides an efficient and stable steam heating solution.

[0160] In another embodiment (energy storage module 50 deep heat release), combined with reference Figure 8 This embodiment describes a steam heating method based on deep heat release of the energy storage module 50, which realizes efficient utilization and deep heat release of the energy storage device through step-by-step heat release of multiple temperature sections and the coordinated work of the heat pump device 20, and specifically includes the following steps:

[0161] S110, during the valley electricity period, the low melting point molten salt having an initial temperature of the eighth temperature (such as 40° C.) is heated to the first temperature (such as 90° C.) by the heat pump device 20. This process makes full use of the low cost valley electricity and the efficient heating capacity of the heat pump to provide a basic heat reserve for subsequent molten salt electric heating.

[0162] S120, during valley power period or flat power low load period, the molten salt is heated from the first temperature to a fourth temperature (eg, 400° C.) by the electric heater 51. This step lays the foundation for the high enthalpy output of the energy storage module 50, ensuring sufficient heat reserve during the steam supply period.

[0163] S130, during the steam demand period, the molten salt of part of the energy storage module 50 is released from the fourth temperature to the fifth temperature (such as 200°C), and superheated steam of the second temperature (such as 180-370°C) is generated through the heat exchange pipeline. In this stage, a multi-channel steam generation path with a parallel structure is used to meet the set steam demand flow.

[0164] S140, when the molten salt of some energy storage modules 50 releases heat to the fifth temperature, by switching the heat exchange pipeline to the series mode, these modules provide high-temperature water preheating for the energy storage modules 50 that are still in a high-temperature state (fourth temperature), and further release heat to the sixth temperature (such as 120° C.). This step optimizes the energy utilization efficiency of the high-temperature section molten salt and realizes the gradient cooperative heat release of the energy storage modules 50.

[0165] S150, after the molten salt releases heat to the sixth temperature, the low-temperature water is heated to the first temperature (such as 90°C) and stored by adjusting the flow of the heat exchange pipeline. This stage adopts a low-flow operation mode to maximize heat recovery and further release heat to the seventh temperature (such as 100°C) of the molten salt.

[0166] S160, the molten salt that releases heat to the seventh temperature is used to provide hot water to the water source heat pump, and the water source heat pump further heats the hot water to the first temperature (such as 90° C.) and stores it. This step releases heat to the eighth temperature (such as 40° C.) through the efficient energy recovery of the heat pump device 20, completing the deep heat release cycle of the energy storage module 50.

[0167] S170: When the molten salt of all energy storage modules 50 releases heat to the eighth temperature, restart step S110, preheat the molten salt through the heat pump device 20, and enter the next cycle. At the same time, dynamically adjust the heat release mode (parallel or series) and operating parameters of the energy storage module 50 to meet the real-time steam demand of the user side.

[0168] Preferably, in step S140, the fifth temperature is higher than the second temperature by a second temperature difference, and the second temperature difference ranges from 20 to 50°C; the sixth temperature is higher than the first temperature by a third temperature difference, and the third temperature difference ranges from 10 to 30°C; the fourth temperature is higher than the sixth temperature by a fourth temperature difference, and the fourth temperature difference is greater than the sum of the second temperature difference and the third temperature difference.

[0169] This embodiment achieves deep utilization of the energy storage module 50 by releasing heat in stages and step by step. The switching between parallel and series modes optimizes the collaborative efficiency of the energy storage module 50 in different temperature ranges, significantly improving the response speed and stability of steam supply. At the same time, through the preheating and waste heat recovery of the heat pump device 20, low-cost valley electricity and low-temperature waste energy are fully utilized, the operating cost is reduced, the economy and environmental adaptability of the system are enhanced, and an efficient and stable solution is provided for industrial steam use under complex working conditions.

[0170] The above-mentioned embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present invention. It should be pointed out that, for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the present invention, and various implementation steps can be combined, which all belong to the protection scope of the present invention; therefore, the protection scope of the present invention shall be subject to the attached claims.

Claims

1. A configuration method for an energy storage coupled heat pump heating system, characterized in that: The following steps are involved: According to the heat load demand during the heating period, the total enthalpy value H of the required heat carrier is quantified; The investment payback period of the single molten salt heating scheme and the energy storage coupled heat pump heating scheme is calculated respectively, where: The single molten salt heating solution calculates the payback period through the initial investment and the savings in operating costs; The energy storage coupled heat pump heating solution allocates the total enthalpy value H required by the user into the first enthalpy increment h provided by the heat pump device and the second enthalpy increment (Hh) provided by the energy storage device, and calculates the investment payback period in combination with the system operation efficiency and electricity price; The payback periods of the single molten salt heating scheme and the energy storage coupled heat pump heating scheme are compared with the target payback period set by the user to determine the best scheme.

2. The configuration method according to claim 1, characterized in that: The transformer capacity during off-peak hours is further considered in the payback period calculation, and includes the following steps: When the transformer capacity is sufficient, it is implemented according to the quantification of heating demand and enthalpy distribution; When the transformer capacity is insufficient, the investment payback period with and without capacity expansion is calculated separately, where: In case of capacity expansion, add the transformer expansion cost to the initial investment; Without capacity expansion, the allowable steam supply can be inferred from the transformer surplus capacity to calculate the investment payback period of partial replacement heating; Compare the payback period of expanding capacity with that of not expanding capacity, and choose the shorter option.

3. The configuration method according to claim 2, characterized in that: The processing without capacity expansion includes: Use the surplus capacity of the transformer during off-peak hours to reversely calculate the allowable steam supply and make partial substitution; The shortfall will be supplied by flat-bed electricity, and the comprehensive investment payback period will be calculated.

4. The configuration method according to claim 2, characterized in that: The processing without capacity expansion includes: Use the surplus capacity of the transformer during off-peak hours to reversely calculate the allowable steam supply and make partial substitution; The remaining heating demand is partially supplemented by gas boilers, and the investment payback period is recalculated.

5. The configuration method according to claim 1, characterized in that: In the enthalpy distribution, the first enthalpy increment h provided by the heat pump device is increased, and the steps are as follows: The heat pump device heats the heat carrier to a first temperature close to the saturation temperature and stores the heat carrier in a pressurized heat-insulating water tank; The first temperature range is set according to the heating capacity of the heat pump unit and includes a temperature range of 90°C to 140°C; The internal pressure of the pressurized insulated water tank is dynamically adjusted according to the saturation temperature to maintain the liquid state of the heat carrier.

6. The configuration method according to claim 1, characterized in that: The molten salt of the energy storage device is preheated by using a heat pump device, and the steps include: During off-peak hours, when the transformer's remaining capacity allows, the heat pump device is used to preheat the molten salt to a temperature close to the maximum heating temperature of the heat pump; The molten salt preheating process is completed through a heat exchange pipeline arranged inside the energy storage device, which is used to improve the initial heat storage state of the molten salt.

7. The configuration method according to claim 6, characterized in that: The energy storage device comprises at least one energy storage module, the energy storage module comprises an outer cylinder and an inner cylinder, the inner cylinder is arranged inside the outer cylinder, an energy storage medium is arranged between the outer cylinder and the inner cylinder, and the heat exchange pipeline comprises a first heat exchange pipeline arranged in the outer cylinder and a second heat exchange pipeline arranged in the inner cylinder; The second heat exchange pipeline is also used for preheating the heat storage medium whose temperature is lower than the first temperature.

8. The configuration method according to claim 1, characterized in that: The energy storage device uses low melting point molten salt material to achieve deep heat release and includes the following steps: During the heating period, when the energy storage modules of some or all energy storage devices release heat to the set minimum temperature, the heat exchange pipelines are used to continue to provide heat to the cold water or low-level heat source; The melting point of the molten salt material is lower than the set minimum temperature.

9. An energy storage coupled heat pump heating system, characterized in that: include: A heat pump device, used to heat a heat carrier to a first temperature and provide a first enthalpy increment h; An energy storage device, used to further heat the heat carrier heated to the first temperature by the heat pump device to a second temperature during the heating period, thereby providing a second enthalpy increment (Hh); The control module is used to dynamically allocate the first enthalpy increment h and the second enthalpy increment (Hh) according to the heat load demand, so as to realize the coordinated operation of the heat pump device and the energy storage device, and at the same time optimize the investment payback period of the system by combining the electricity price conditions and the system operation efficiency.

10. The energy storage coupled heat pump heating system according to claim 9, characterized in that: The heat pump device comprises: A waste heat source heat pump, used to determine whether to start the waste heat source heat pump to use the waste heat resources to provide a part of the first enthalpy increment according to the waste heat resources available in the factory and the operation status during the valley power period and the heating period; The air source heat pump is used to dynamically evaluate the availability of the external environmental heat source according to the meteorological temperature conditions, and determine whether to start the air source heat pump to supplement the first enthalpy increment when the waste heat is insufficient or unavailable.

11. The energy storage coupled heat pump heating system according to claim 9, characterized in that: The control module supports comparison of the payback period of a single molten salt heating scheme and an energy storage coupled heat pump heating scheme based on the user's expected payback period, and dynamically adjusts the enthalpy distribution ratio h:(Hh) to optimize the system design scheme.

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