Electric heating steam storage, supply and upgrading coupling system and operation control method

Abstract

The invention discloses an electric heating steam storage, supply and upgrading coupling system which comprises an electrode steam boiler-spherical tank storage and supply system, a steam compressor system and an external steam source. The electrode steam boiler generates high-pressure steam, and the high-pressure steam is distributed to the spherical tank for heat storage or pressure reduction through the high-pressure steam-distributing cylinder and then fed into the medium-low-pressure steam-distributing cylinder. When the spherical tank releases heat, steam with corresponding parameters is output through different flash pressure reducing valves, is converged into a medium-low pressure steam header, passes through a steam electric heater and then is divided into three paths to be matched with a steam compressor system. The steam compressor system improves the quality of input steam, and independent external steam source steam supply, independent storage and supply system steam supply and combined steam supply are achieved through valve control. According to the system, valley electricity or new energy is utilized, through multi-mode switching and parameter regulation and control, the initial investment and operation cost of a project are reduced, safety and reliability are improved, the whole process of demineralized water supply, steam preparation, storage and supply, quality improvement and external steam supply can be completed, and the system is suitable for efficient supply of industrial steam and energy-saving and consumption-reducing transformation.

Description

Technical Field

[0001] This invention belongs to the field of novel energy storage technology, specifically relating to thermal energy storage devices and technologies. It specifically refers to an electric heating steam storage and supply coupled system that uses off-peak electricity or absorbs new energy sources such as wind power and photovoltaic power for energy conversion, storage and supply by coupling the functions of electric heating steam preparation, storage and supply, in order to achieve energy-saving and consumption-reducing transformation and build an efficient energy storage system. Background Technology

[0002] With the increasing global demand for clean energy and the growing urgency of addressing climate change, power systems with a high proportion of renewable energy are gradually taking shape. Simultaneously, the development of the electricity spot market and the improvement of peak-valley time-of-use pricing mechanisms have further widened the price gap between peak and off-peak electricity prices. Against this backdrop, new energy storage technologies have emerged. These technologies can fully utilize the price fluctuations in the electricity spot market and the peak-valley time-of-use pricing mechanism to generate steam and store heat during off-peak hours, and then release heat to supply steam during peak hours to earn the price difference, thereby optimizing energy costs and improving economic efficiency.

[0003] However, existing thermal storage and steam upgrading technologies still face many unresolved issues. For example, while molten salt thermal storage technology achieves thermal storage to some extent, its initial investment cost is high, and molten salt carries the risk of crystallization, which not only increases the complexity of system maintenance but also reduces the overall system's safety and reliability. Furthermore, existing technologies that use steam compressors to upgrade low-parameter steam before resupplying it result in significantly increased costs during peak electricity price periods due to the consumption of peak-price electricity. This means that electricity consumers face higher peak-price electricity costs, and for scenarios coupled with coal-fired power units, they face higher opportunity costs for peak-price grid connection, making them economically uncompetitive. In addition, for electrode boilers of the same power and spherical tanks of the same volume coupled with thermal storage and steam supply technology, although they have certain thermal storage and steam supply capabilities, there is still potential to be tapped. Further optimization is needed to convert more low-cost electricity into high-priced industrial steam during off-peak electricity price periods (i.e., more efficient conversion of off-peak electricity price cost for the electricity consumer side, and more efficient conversion of off-peak electricity price opportunity cost for the coupled scenario with coal-fired power units), while reducing the electricity cost or opportunity cost during peak hours (corresponding to peak electricity price cost for the electricity consumer side or peak electricity price opportunity cost for the coupled scenario with coal-fired power units).

[0004] To address these challenges, this invention discloses an electrically heated steam storage, supply, and upgrading coupled system. This system achieves coordinated steam supply by organically coupling an electrode steam boiler system, a spherical tank thermal storage and steam supply system, and a steam compression and upgrading system. This innovative system design not only effectively reduces initial project investment but also significantly improves system safety and reliability while substantially reducing operating costs. It adapts to the actual steam supply needs of industrial sectors, providing a feasible technical solution for the application of novel energy storage technologies in industrial thermal scenarios. Summary of the Invention

[0005] The purpose of this invention is to address the shortcomings of existing thermal storage and steam upgrading technologies, such as the high initial investment and crystallization risk of molten salt thermal storage, the high operating costs of existing steam compressor technology during peak electricity price periods (electricity cost on the electricity consumption side, opportunity cost in coal-fired power unit coupling scenarios), and the need to improve the efficiency of traditional electrode steam boiler and spherical tank coupling technology. The invention aims to provide an electrically heated steam storage, supply, and upgrading coupling system to reduce initial project investment, improve system safety and reliability, reduce operating costs (electricity cost on the electricity consumption side, opportunity cost in coal-fired power unit coupling scenarios), and efficiently utilize off-peak electricity or new energy sources for steam preparation, storage, supply, and upgrading, thereby meeting the stable and efficient supply needs of industrial steam.

[0006] To achieve the above objectives, this invention proposes an electrically heated steam storage and supply coupled system for quality improvement, comprising an electrode steam boiler-spherical tank storage and supply system, a steam compressor system, and an external steam source;

[0007] The steam outlet pipeline of the electrode steam boiler-spherical tank storage and supply system is divided into three branches, which connect to the steam compressor system: the first branch connects to the steam outlet pipeline of the steam compressor system, and the two branches merge to form an external output pipeline to supply industrial steam; the second and third branches merge with the output pipeline of the external steam source to form a main pipeline, which connects to the steam inlet of the steam compressor system; a compressor bypass electric gate valve is installed on the first branch of the steam outlet pipeline from the electrode steam boiler-spherical tank storage and supply system to the steam outlet pipeline of the steam compressor system; a compressor inlet pressure reducing valve is installed on the second branch of the steam outlet pipeline from the electrode steam boiler-spherical tank storage and supply system to the steam inlet pipeline of the steam compressor system; a compressor inlet straight-through electric gate valve is installed on the third branch of the steam outlet pipeline from the electrode steam boiler-spherical tank storage and supply system to the steam inlet pipeline of the steam compressor system; and an external steam source flow regulating valve is installed on the connecting pipeline from the external steam source to the steam inlet pipeline of the steam compressor system.

[0008] The electrode steam boiler-spherical tank storage and supply system includes an electrode steam boiler, a high-pressure steam distribution cylinder, a spherical tank, a medium and low-pressure steam distribution cylinder, a steam electric heater, a demineralized water supply tank, a deaerator, a deaerator water supply pump, a spherical tank water supply pump, and a boiler feed water pump.

[0009] The first makeup water inlet of the demineralized water makeup water tank is connected to the chemical demineralized water system via a pipeline; the second makeup water outlet of the demineralized water makeup water tank is connected to the makeup water inlet of the deaerator makeup water pump via a pipeline; the third makeup water outlet of the demineralized water makeup water tank is connected to the first makeup water inlet of the spherical tank via a pipeline; the makeup water outlet of the deaerator makeup water pump is connected to the first makeup water inlet of the deaerator via a pipeline; the second steam inlet of the deaerator is connected to the fourth steam outlet of the medium and low pressure steam separator via a pipeline, and a pressure reducing and stabilizing valve can be installed on this pipeline; the third feedwater outlet of the deaerator is connected to the feedwater inlet of the boiler feedwater pump via a pipeline; the feedwater outlet of the boiler feedwater pump is connected to the feedwater inlet of the electrode steam boiler via a pipeline; the steam outlet of the electrode steam boiler is connected to the high pressure steam separator via a pipeline. The first steam inlet; the second steam outlet of the high-pressure steam distributor is connected to the second steam inlet of the medium-low pressure steam distributor via a pipeline, and this pipeline is equipped with a boiler direct supply pressure reducing valve; the third steam outlet of the high-pressure steam distributor is connected to the second steam inlet of the spherical tank via a pipeline; one steam pipeline of the third steam outlet of the spherical tank is divided into two parallel pipelines, and then merged into a steam pipeline connected to the first steam inlet of the medium-low pressure steam distributor: wherein the first pipeline is equipped with a high- and medium-pressure section flash pressure reducing valve, and the second pipeline is equipped with a medium- and low-pressure section flash pressure reducing valve; the third steam outlet of the medium- and low-pressure steam distributor is connected to the steam inlet of the steam electric heater via a pipeline; the steam outlet pipeline of the steam electric heater is the steam outlet pipeline of the electrode steam boiler-spherical tank storage and supply system; the electrode steam boiler is equipped with a high-pressure electrode.

[0010] The steam compressor system includes a steam compressor, a compressor inlet desuperheating device, and a compressor outlet desuperheating device; the steam inlet of the steam compressor is connected to the steam outlet of the compressor inlet desuperheating device; the steam inlet pipe of the compressor inlet desuperheating device is the steam inlet pipe of the steam compressor system; the steam outlet of the steam compressor is connected to the steam inlet of the compressor outlet desuperheating device; the steam outlet pipe of the compressor outlet desuperheating device is the steam outlet pipe of the steam compressor system; the steam compressor is preferably equipped with a variable frequency speed control motor.

[0011] The external steam source flow regulating valve can adjust the steam supply of the external steam source, while also controlling the ratio between the steam flow rate provided by the electrode steam boiler-spherical tank storage and supply system at the steam inlet of the steam compressor and the steam flow rate provided by the external steam source.

[0012] The steam compressor stabilizes the outlet steam pressure through variable frequency speed control technology, ensures that the superheat of the inlet steam does not exceed the limit by means of the compressor inlet desuperheating device, and maintains a constant outlet steam temperature by means of the compressor outlet desuperheating device.

[0013] The steam compressor can be equipped with an anti-surge backflow pipeline and an anti-surge backflow valve, which are used to stabilize the working state through backflow adjustment during surge conditions, ensuring safe and stable operation.

[0014] In the electric heating steam storage and supply and quality improvement coupling system, key equipment such as electrode steam boiler, high-pressure steam distribution cylinder, spherical tank, medium and low-pressure steam distribution cylinder, and deaerator are all equipped with safety valves. When the pressure rises to the set pressure, the valves automatically open to release pressure, which can effectively avoid equipment damage or safety accidents caused by overpressure.

[0015] In this embodiment, each device is configured as one unit. As an improvement to the technical solution, the electric heating steam storage and supply and quality improvement coupling system can be flexibly set according to the actual storage and supply scale, equipment capacity and site conditions. Among them, electrode steam boiler, spherical tank, steam electric heater, deaerator water supply pump, spherical tank water supply pump, boiler feed water pump, steam compressor, etc., can be configured in parallel with multiple units according to relevant standards, specifications and usage requirements.

[0016] The beneficial effects of this invention are:

[0017] 1. Reduce costs and risks: Using spherical tank thermal storage instead of molten salt thermal storage significantly reduces the initial investment of the project, avoids the risk of molten salt crystallization, reduces maintenance complexity, and improves the safety and reliability of the system.

[0018] 2. Optimize economic efficiency: By storing heat from off-peak electricity or new energy sources and releasing heat to supply steam during peak hours, reduce electricity consumption during peak electricity price periods, lower operating costs (or opportunity costs), and improve the utilization efficiency of off-peak electricity and new energy sources.

[0019] 3. Flexible adaptation to needs: Through multi-mode and multi-operation steam supply and staged flash evaporation and quality improvement regulation, steam sources with different pressures can be uniformly processed into industrial steam that meets specific parameter requirements, accurately matching the parameter requirements of steam use scenarios and effectively improving the applicability of the system.

[0020] 4. Highly efficient and coordinated operation: The electrode steam boiler-spherical tank storage and supply system is coupled and coordinated with the steam compressor system to realize the integration of the entire process of steam "preparation-storage and supply-quality improvement", improve energy conversion and supply efficiency, and provide an effective solution for energy saving and consumption reduction in the industrial steam field.

[0021] 5. Significantly enhances thermal storage and revenue potential: By coupling with a steam compressor system, the thermal storage capacity is greatly increased (e.g., a project is equipped with two 20kV / 70MW electrode steam boilers and four 850m³ / h steam compressors). 3 When using spherical tanks, the thermal storage capacity increases from 269MWh to 351MWh, an increase of 30.5%. This improvement stems from the synergy between the flash evaporation efficiency of the spherical tanks and the quality improvement function of the steam compressor after system coupling, which can significantly increase the consumption of off-peak electricity or new energy power, directly bringing revenue growth to enterprises. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this invention. For those skilled in the art, other drawings can be obtained based on these drawings.

[0023] Figure 1 This is a schematic diagram of an electrically heated steam storage and supply coupled with a quality improvement system according to the present invention;

[0024] Figure label:

[0025] 1-Electrode steam boiler-spherical tank storage and supply system; 2-Steam compressor system; 3-Compressor bypass electric gate valve; 4-Compressor inlet pressure reducing valve; 5-Compressor inlet direct-connect electric gate valve; 6-External steam source flow regulating valve; 1.1-Electrode steam boiler; 1.2-High-pressure steam distributor; 1.3-Spherical tank; 1.4-Medium and low-pressure steam distributor; 1.5-Steam electric heater; 1.6-Demineralized water makeup tank; 1.7-Deaerator; 1.81-Deaerator makeup water pump; 1.82-Spherical tank makeup water pump; 1.83-Boiler feed water pump; 1.91-High and medium-pressure section flash steam pressure reducing valve; 1.92-Medium and low-pressure section flash steam pressure reducing valve; 1.93-Boiler direct supply pressure reducing valve; 1.10-High-pressure electrode; 2.1-Steam compressor; 2.2-Compressor inlet desuperheating device; 2.3-Compressor outlet desuperheating device. Detailed Implementation

[0026] To enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings.

[0027] Unless otherwise expressly specified and limited, the terms "first, second, third or fourth" are used for descriptive purposes only and should not be construed as indicating or implying relative importance; the terms "connected" or "linked" should be interpreted broadly, for example, they can be fixed connections, detachable connections or integral connections, they can be mechanical connections, electrical connections or direct connections, they can also be indirect connections through an intermediate medium, or they can be the internal connection of two components.

[0028] like Figure 1 As shown, the present invention discloses an electric heating steam storage and supply coupled system for quality improvement, including an electrode steam boiler-spherical tank storage and supply system 1, a steam compressor system 2, and an external steam source;

[0029] The steam outlet pipeline of the electrode steam boiler-spherical tank storage and supply system 1 is divided into three branches, which are connected to the steam compressor system 2: the first branch connects to the steam outlet pipeline of the steam compressor system 2, and the two branches merge to form an external output pipeline to supply industrial steam; the second and third branches merge with the output pipeline of the external steam source to form a main pipeline, which connects to the steam inlet of the steam compressor system 2; a compressor bypass electric gate valve 3 is installed on the first branch from the steam outlet pipeline of the electrode steam boiler-spherical tank storage and supply system 1 to the steam outlet pipeline of the steam compressor system 2; a compressor inlet pressure reducing valve 4 is installed on the second branch from the steam outlet pipeline of the electrode steam boiler-spherical tank storage and supply system 1 to the steam inlet pipeline of the steam compressor system 2; a compressor inlet straight-through electric gate valve 5 is installed on the third branch from the steam outlet pipeline of the electrode steam boiler-spherical tank storage and supply system 1 to the steam inlet pipeline of the steam compressor system 2; and an external steam source flow regulating valve 6 is installed on the connecting pipeline from the external steam source to the steam inlet pipeline of the steam compressor system 2.

[0030] The electrode steam boiler-spherical tank storage and supply system 1 includes an electrode steam boiler 1.1, a high-pressure steam distributor 1.2, a spherical tank 1.3, a medium and low-pressure steam distributor 1.4, a steam electric heater 1.5, a demineralized water supply tank 1.6, a deaerator 1.7, a deaerator water supply pump 1.81, a spherical tank water supply pump 1.82, and a boiler feed water pump 1.83.

[0031] The first makeup water inlet of the demineralized water makeup water tank 1.6 is connected to the chemical demineralized water system via a pipeline; the second makeup water outlet of the demineralized water makeup water tank 1.6 is connected to the makeup water inlet of the deaerator makeup water pump 1.81 via a pipeline; the third makeup water outlet of the demineralized water makeup water tank 1.6 is connected to the first makeup water inlet of the spherical tank 1.3 via a pipeline; the makeup water outlet of the deaerator makeup water pump 1.81 is connected to the first makeup water inlet of the deaerator 1.7 via a pipeline; the second steam inlet of the deaerator 1.7 is connected to the fourth steam outlet of the medium-low pressure steam separator 1.4 via a pipeline, and a pressure reducing and stabilizing valve can be installed on this pipeline; the third feedwater outlet of the deaerator 1.7 is connected to the feedwater inlet of the boiler feedwater pump 1.83 via a pipeline; the feedwater outlet of the boiler feedwater pump 1.83 is connected to the feedwater inlet of the electrode steam boiler 1.1 via a pipeline; and the steam outlet of the electrode steam boiler 1.1 is connected to the high pressure steam separator 1.2 via a pipeline. The first steam inlet of the high-pressure steam distributor 1.2 is connected to the second steam inlet of the medium-low pressure steam distributor 1.4 via a pipeline, and a boiler direct supply pressure reducing valve 1.93 is installed on this pipeline; the third steam outlet of the high-pressure steam distributor 1.2 is connected to the second steam inlet of the spherical tank 1.3 via a pipeline; one steam pipeline of the third steam outlet of the spherical tank 1.3 is divided into two parallel pipelines, and then merged into a steam pipeline connected to the first steam inlet of the medium-low pressure steam distributor 1.4: the first pipeline is equipped with a high-medium pressure section flash pressure reducing valve 1.91, and the second pipeline is equipped with a medium-low pressure section flash pressure reducing valve 1.92; the third steam outlet of the medium-low pressure steam distributor 1.4 is connected to the steam inlet of the steam electric heater 1.5 via a pipeline; the steam outlet pipeline of the steam electric heater 1.5 is the steam outlet pipeline of the electrode steam boiler-spherical tank storage and supply system 1; a high-pressure electrode 1.10 is installed on the electrode steam boiler 1.1.

[0032] The steam compressor system 2 includes a steam compressor 2.1, a compressor inlet desuperheating device 2.2, and a compressor outlet desuperheating device 2.3; the steam inlet of the steam compressor 2.1 is connected to the steam outlet of the compressor inlet desuperheating device 2.2; the steam inlet pipe of the compressor inlet desuperheating device 2.2 is the steam inlet pipe of the steam compressor system 2; the steam outlet of the steam compressor 2.1 is connected to the steam inlet of the compressor outlet desuperheating device 2.3; the steam outlet pipe of the compressor outlet desuperheating device 2.3 is the steam outlet pipe of the steam compressor system 2; the steam compressor 2.1 is preferably equipped with a variable frequency speed control motor.

[0033] The external steam source flow regulating valve 6 can regulate the steam supply of the external steam source, while also controlling the ratio between the steam flow rate provided by the electrode steam boiler-spherical tank storage and supply system 1 at the steam inlet of the steam compressor 2.1 and the steam flow rate provided by the external steam source.

[0034] The steam compressor 2.1 stabilizes the outlet steam pressure through variable frequency speed control technology, ensures that the superheat of the inlet steam does not exceed the limit with the help of the compressor inlet desuperheating device 2.2, and maintains a constant outlet steam temperature through the compressor outlet desuperheating device 2.3.

[0035] The steam compressor 2.1 can be equipped with an anti-surge backflow pipeline and an anti-surge backflow valve, which are used to stabilize the working state through backflow adjustment during surge conditions, ensuring safe and stable operation.

[0036] In the electric heating steam storage and supply and quality improvement coupling system, key equipment such as the electrode steam boiler 1.1, high-pressure steam distribution cylinder 1.2, spherical tank 1.3, medium and low-pressure steam distribution cylinder 1.4, and deaerator 1.7 are all equipped with safety valves. When the pressure rises to the set pressure, the valves automatically open to release pressure, which can effectively avoid equipment damage or safety accidents caused by overpressure.

[0037] In this embodiment, each device is configured as one unit. As an improvement to the technical solution, the electric heating steam storage and supply and quality improvement coupling system can be flexibly set according to the actual storage and supply scale, equipment capacity and site conditions. Among them, electrode steam boiler 1.1, spherical tank 1.3, steam electric heater 1.5, deaerator water supply pump 1.81, spherical tank water supply pump 1.82, boiler feed water pump 1.83, steam compressor 2.1, etc., can be configured in parallel with multiple units according to relevant standards, specifications and usage requirements.

[0038] Working process of this invention:

[0039] The chemically demineralized water provided by the chemical demineralized water system is first stored in the demineralized water makeup tank 1.6. This demineralized water is distributed via two paths: one path is sent to the deaerator 1.7 via the deaerator makeup water pump 1.81, and the other path is sent to the spherical tank 1.3 via the spherical tank makeup water pump 1.82. The heating steam for the deaerator 1.7 comes from the medium-low pressure steam distribution cylinder 1.4. The deaerated feedwater is sent to the electrode steam boiler 1.1 by the boiler feed water pump 1.83. In the electrode steam boiler 1.1, the feedwater is heated by the high-pressure electrode 1.10 to generate high-pressure saturated steam. This high-pressure saturated steam enters the high-pressure steam distribution cylinder 1.2 and is then divided into two output paths:

[0040] The first high-pressure steam is reduced to medium-pressure steam parameters through the boiler direct supply pressure reducing valve 1.93, and then sent to the medium and low-pressure steam distribution cylinder 1.4;

[0041] The second high-pressure steam is directly introduced into the spherical tank 1.3, and through heat exchange, the low-pressure medium inside the tank is heated into high-parameter saturated water and saturated steam, thereby completing the heat storage process.

[0042] The heat release process in spherical tank 1.3 is achieved through the following path: the stored high-parameter medium is led out through a main pipe and then split into two paths for flash evaporation and pressure reduction, respectively adapted to different pressure requirements:

[0043] The first medium is used to reduce the pressure of the high-pressure saturated water in the spherical tank to medium pressure. After being flashed and depressurized by the high-medium pressure section flash pressure reducing valve 1.91, it is converted into medium pressure steam and sent to the medium-low pressure steam distribution cylinder 1.4.

[0044] The second medium is used for the process of reducing the pressure of the medium-pressure saturated water in the spherical tank to low pressure. After being flashed and depressurized by the medium-low pressure section flash pressure reducing valve 1.92, it is converted into low-pressure steam and sent to the medium-low pressure steam distribution cylinder 1.4.

[0045] Steam in the medium-low pressure steam distribution cylinder 1.4 is heated by the steam electric heater 1.5 and then led out through a main pipe. It is then divided into three paths to work in coordination with the steam compressor system 2 to ultimately supply steam to the outside. The specific process is as follows:

[0046] The first steam path passes through the compressor bypass electric gate valve 3 and is directly connected to the outlet steam pipeline of the compressor outlet desuperheating device 2.3 in the steam compressor system 2, where it merges with (or separately supplies) the steam in the pipeline to the outside for industrial steam supply.

[0047] The second steam stream passes through the compressor inlet pressure reducing valve 4, and the third steam stream passes through the compressor inlet direct-acting electric gate valve 5. They do not simultaneously merge with the steam output from the external steam source via the external steam source flow regulating valve 6 to form a single main pipe. The mixed steam in this main pipe (or a single steam stream, or a mixture of two steam streams) first enters the compressor inlet desuperheating device 2.2 for temperature regulation, and then is sent to the steam compressor 2.1. After being upgraded (pressure and temperature increased) by the steam compressor 2.1, the steam enters the compressor outlet desuperheating device 2.3 to complete the final temperature control, and then merges with (or separately from) the first steam stream to supply industrial steam to the outside.

[0048] Through the above working process, the electric heating steam storage and supply and quality improvement coupling system of the present invention can realize the complete process of demineralized water replenishment, steam preparation, heat storage and release, multi-parameter steam regulation and external steam supply. The coordinated action of each valve, pump group and equipment ensures the stable flow of the medium under different parameters and different paths.

[0049] This invention relates to an industrial steam supply mode:

[0050] 1) External steam source independent steam supply mode: The electrode steam boiler-spherical tank storage and supply system 1 does not supply industrial steam to the outside world. It only supplies industrial steam to the outside world through the external steam source flow regulating valve 6, the compressor inlet desuperheating device 2.2, the steam compressor 2.1, and the compressor outlet desuperheating device 2.3 in sequence.

[0051] 2) Electrode Steam Boiler-Spherical Tank Storage and Supply System 1 Independent Steam Supply Mode: The external steam source does not provide industrial steam to the outside world, but only provides industrial steam to the outside world through the electrode steam boiler-spherical tank storage and supply system 1.

[0052] 3) Combined steam supply mode of external steam source and electrode steam boiler-spherical tank storage and supply system 1 (hereinafter referred to as "combined steam supply mode"): The external steam source and electrode steam boiler-spherical tank storage and supply system 1 operate in coordination and supply industrial steam to the outside at the same time.

[0053] Operation mode of electrode steam boiler-spherical tank storage and supply system 1 under independent steam supply mode:

[0054] For ease of analysis, the influence of pressure drop is ignored, and the following steam pressure parameters are set: high-pressure steam with pressure PH (the outlet steam pressure of electrode steam boiler 1.1 and the high pressure of spherical tank 1.3 are both PH), medium-pressure steam with pressure PM (the medium pressure of spherical tank 1.3, the outlet steam pressure of steam compressor 2.1 and the industrial steam pressure are both PM), and low-pressure steam with pressure PL (the low pressure of spherical tank 1.3, the external steam source pressure, the outlet steam pressure of compressor inlet pressure reducing valve 4, and the inlet steam pressure of steam compressor 2.1 are all PL).

[0055] 1) Boiler direct supply via compressor bypass steam supply method: This method does not use the flash steam supply through the spherical tank 1.3, but only uses the high-pressure steam with a pressure of PH generated by the electrode steam boiler 1.1. The steam is then reduced to medium-pressure steam with a pressure of PM through the high-pressure steam distributor 1.2 and the boiler direct supply pressure reducing valve 1.93. The steam is then heated to the temperature required for industrial steam through the medium and low pressure steam distributor 1.4 and the steam electric heater 1.5. Finally, the steam is sent to the outlet steam pipeline of the compressor outlet desuperheating device 2.3 through the compressor bypass electric gate valve 3, and industrial steam is supplied separately to the outside.

[0056] 2) High-pressure to medium-pressure saturated water flash evaporation in spherical tanks via compressor bypass steam supply method: This method does not generate steam through electrode steam boiler 1.1 and supply steam to the outside via boiler direct supply pressure reducing valve 1.93. Instead, it uses the medium-pressure steam generated by flash evaporation of saturated water in spherical tank 1.3 during the process of pressure dropping from PH (high pressure) to PM (medium pressure). This medium-pressure steam is then successively heated to the required temperature for industrial steam by medium and low pressure steam distribution cylinder 1.4 and steam electric heater 1.5. Subsequently, it is sent to the outlet steam pipeline of compressor outlet desuperheating device 2.3 via compressor bypass electric gate valve 3, and industrial steam is supplied to the outside separately.

[0057] 3) Steam supply method via saturated water flash evaporation from medium to low pressure in spherical tank and compressor body: This method does not generate steam through electrode steam boiler 1.1 and supply steam to the outside via boiler direct supply pressure reducing valve 1.93. Instead, it uses the low-pressure steam generated by flash evaporation of saturated water in spherical tank 1.3 during the process of pressure dropping from PM (medium pressure) to PL (low pressure). This low-pressure steam is then sequentially heated to the required inlet temperature of steam compressor 2.1 by medium and low pressure steam distribution cylinder 1.4 and steam electric heater 1.5. Subsequently, it is sequentially heated to the industrial steam parameters (pressure of PM) by compressor inlet direct electric gate valve 5, compressor inlet desuperheating device 2.2, steam compressor 2.1, and compressor outlet desuperheating device 2.3. After being upgraded (pressurized and heated), it is supplied to the outside industrial steam separately.

[0058] 4) Combined boiler direct supply and high-pressure to medium-pressure saturated water flash evaporation from the spherical tank, via compressor bypass steam supply method: High-pressure steam (PH) generated by electrode steam boiler 1.1 is sequentially reduced to medium-pressure steam (PM) through high-pressure steam distributor 1.2 and boiler direct supply pressure reducing valve 1.93, and then connected to medium-low pressure steam distributor 1.4; simultaneously, during the process of the pressure in spherical tank 1.3 decreasing from PH (high pressure) to PM (medium pressure), medium-pressure steam (PM) generated by saturated water flash evaporation is also connected to medium-low pressure steam distributor 1.4. The medium-pressure steam (PM) in medium-low pressure steam distributor 1.4 is heated to the required temperature for industrial steam by steam electric heater 1.5, and then sent to the outlet steam pipeline of compressor outlet desuperheating device 2.3 via compressor bypass electric gate valve 3, supplying industrial steam separately.

[0059] Example 1 of multi-mode and multi-operation mode switching:

[0060] The initial setting is to use an external steam source for independent steam supply. At this time, the compressor bypass electric gate valve 3 and the compressor inlet pressure reducing valve 4 are both closed, while the compressor inlet direct-connect electric gate valve 5 is open. The electrode steam boiler-spherical tank storage and supply system 1 stops supplying steam and is only supplied with low-pressure steam at a pressure of PL by the external steam source.

[0061] When the off-peak electricity price period begins, the following operations are performed simultaneously: Electrode steam boiler 1.1 is simultaneously activated in both the direct boiler supply via compressor bypass mode (compressor bypass electric gate valve 3 remains closed) and the electrode steam boiler 1.1 steam supply to the spherical tank thermal storage mode. The compressor inlet direct-connect electric gate valve 5 is closed. The external steam source supply mode remains operational. As operation progresses, the steam supply pressure of the electrode steam boiler-spherical tank thermal storage system 1 gradually increases from PL. When it reaches PM, the compressor bypass electric gate valve 3 is opened, and the external steam source supply mode is simultaneously deactivated. At this point, both the direct boiler supply via compressor bypass mode and the electrode steam boiler 1.1 steam supply to the spherical tank thermal storage mode are operating normally. During continued operation, the spherical tank pressure gradually increases from PL to PH. At this point, the electrode steam boiler 1.1 steam supply to the spherical tank thermal storage mode is shut down, and only the direct boiler supply via compressor bypass mode continues to operate.

[0062] When the off-peak electricity price period ends and the peak electricity price period begins, the electrode steam boiler 1.1 and the boiler direct supply steam supply via compressor bypass are shut down, and the spherical tank high-pressure to medium-pressure saturated water flash steam supply via compressor bypass is put into operation simultaneously. As operation progresses, the pressure of spherical tank 1.3 gradually decreases from pH but remains higher than PM, and the spherical tank high-pressure to medium-pressure saturated water flash steam supply via compressor bypass is in normal operating condition.

[0063] When the pressure in spherical tank 1.3 drops to PM, the compressor inlet pressure reducing valve 4 is opened, and the compressor inlet desuperheating device 2.2, steam compressor 2.1, and compressor outlet desuperheating device 2.3 are activated. Then, the compressor bypass electric gate valve 3 is closed, cutting off the high-pressure to medium-pressure saturated water flash steam supply via compressor bypass. In subsequent processes, the steam supply pressure of the electrode steam boiler-spherical tank storage and supply system 1 gradually decreases from PM. When the pressure drops to near PL, the medium-pressure to low-pressure saturated water flash steam supply via compressor body is activated, and the compressor inlet direct-connect electric gate valve 5 is opened, followed by closing the compressor inlet pressure reducing valve 4. As operation progresses, although the pressure in spherical tank 1.3 gradually decreases from PM, it remains above PL, and the medium-pressure to low-pressure saturated water flash steam supply via compressor body maintains normal operation.

[0064] When the pressure in tank 1.3 drops to PL, the external steam source is activated, the flash pressure reducing valve 1.92 in the medium and low pressure section is closed, and the flash steam supply mode of the medium-to-low pressure saturated water in the tank via the compressor body is stopped, switching back to the initial external steam source-only steam supply mode. This completes one full cycle of steam supply mode and operation mode switching.

[0065] Example 2 of multi-mode and multi-operation mode switching:

[0066] The initial setting is to use an external steam source for independent steam supply. At this time, the compressor bypass electric gate valve 3 and the compressor inlet pressure reducing valve 4 are both closed, while the compressor inlet direct-connect electric gate valve 5 is open. The electrode steam boiler-spherical tank storage and supply system 1 stops supplying steam and is only supplied with low-pressure steam at a pressure of PL by the external steam source.

[0067] When the off-peak electricity price period begins, the following operations are performed simultaneously: Electrode steam boiler 1.1 is put into operation, and the direct boiler supply via compressor bypass steam supply mode (compressor bypass electric gate valve 3 remains closed) and the electrode steam boiler 1.1 steam supply to the spherical tank heat storage mode are both started. The compressor inlet direct-connect electric gate valve 5 is closed, and the external steam source supply mode continues to operate. As operation progresses, the steam supply pressure of the electrode steam boiler-spherical tank heat storage system 1 gradually increases from PL. When it reaches PM, the compressor bypass electric gate valve 3 is opened, and the external steam source supply mode continues to operate, but the flow rate is reduced to the minimum flow rate required by steam compressor 2.1, forming a coordinated operation state of external steam source supply mode, direct boiler supply via compressor bypass steam supply mode, and electrode steam boiler 1.1 steam supply to the spherical tank heat storage mode. During continued operation, the spherical tank pressure gradually increases from PL. When it reaches PH, the electrode steam boiler 1.1 steam supply to the spherical tank heat storage mode is shut down, and the operation switches to a coordinated operation state of external steam source supply mode and direct boiler supply via compressor bypass steam supply mode.

[0068] When the off-peak electricity price period ends and the peak electricity price period begins, electrode steam boiler 1.1 and the direct boiler-to-compressor bypass steam supply method are shut down. Simultaneously, the high-pressure to medium-pressure saturated water flash steam supply method via compressor bypass is put into operation. The external steam source supply method continues to operate, but the flow rate is reduced to the minimum flow rate required by steam compressor 2.1. This transitions to a coordinated operation of the external steam source supply method and the high-pressure to medium-pressure saturated water flash steam supply method via compressor bypass. As operation progresses, the pressure in spherical tank 1.3 gradually decreases from pH but remains above PM. The coordinated operation of the external steam source supply method and the high-pressure to medium-pressure saturated water flash steam supply method via compressor bypass is in normal operating condition.

[0069] When the pressure in spherical tank 1.3 drops to PM, the compressor inlet pressure reducing valve 4 is opened, and the compressor inlet desuperheating device 2.2, steam compressor 2.1, and compressor outlet desuperheating device 2.3 are activated. Then, the compressor bypass electric gate valve 3 is closed, cutting off the high-pressure to medium-pressure saturated water flash steam supply via compressor bypass mode. The external steam source supply mode continues to operate. In subsequent processes, the steam supply pressure of the electrode steam boiler-spherical tank storage and supply system 1 gradually decreases from PM. When the pressure drops to near PL, the medium-pressure to low-pressure saturated water flash steam supply via compressor body mode is activated. The compressor inlet direct-connect electric gate valve 5 is opened, and then the compressor inlet pressure reducing valve 4 is closed. The external steam source supply mode continues to operate, transitioning to a coordinated operation state of external steam source supply and spherical tank medium-pressure to low-pressure saturated water flash steam supply via compressor body mode. As operation progresses, although the pressure in spherical tank 1.3 gradually decreases from PM, it remains above PL. The coordinated operation of the external steam source supply mode and the spherical tank medium-pressure to low-pressure saturated water flash steam supply via compressor body mode is in normal operating condition.

[0070] When the pressure in spherical tank 1.3 drops to PL, the external steam source supply mode continues to operate, the flash pressure reducing valve 1.92 in the medium and low pressure section is closed, and the flash steam supply mode of the medium to low pressure saturated water in the spherical tank via the compressor body is stopped, switching back to the initial external steam source independent steam supply mode. This completes one complete cycle of steam supply mode and operating mode switching.

[0071] It should be noted that in the switching logic of this embodiment 2, the steam compressor 2.1 maintains continuous operation under most operating conditions, with relatively few start-stop cycles. This operating characteristic can reduce mechanical wear caused by frequent start-stop cycles, which is beneficial to extending the service life of the steam compressor 2.1.

[0072] The electric heating steam storage, supply, and upgrading coupling system disclosed in this invention involves key pressure parameters such as high-pressure parameter (PH), medium-pressure parameter (PM), and low-pressure parameter (PL). These parameters are specifically adapted to this electric heating steam storage, supply, and upgrading coupling system. The system achieves switching between different operating modes and procedures by dividing the aforementioned pressure parameters into ranges. In practical applications, the determination of each pressure parameter needs to comprehensively consider the pressure drop and allowable deviation range under actual operating conditions to accurately adapt to the pressure requirements and fluctuations in actual operating conditions.

[0073] Example 3 of an electrically heated steam storage and supply coupled with quality improvement system:

[0074] A certain project is equipped with two 20kV / 70MW electrode steam boilers and four 850m³ / h electrode steam boilers. 3The spherical tanks, with the electrode steam boiler having a rated steam pressure of 3.1 MPa.g and the spherical tanks operating at a pressure of 3.1 MPa.g, meet industrial steam requirements of 0.8 MPa.g and 280℃. The spherical tank filling factor is designed to be 0.90. When using only the electrode steam boiler-spherical tank storage and supply system, the single-use thermal storage capacity of the four spherical tanks is 269 MWh. When coupled with a steam compressor system to form an electrically heated steam storage and supply and quality improvement coupled system (with the steam compressor inlet / outlet pressures set at 0.4 MPa.g / 0.8 MPa.g), the single-use thermal storage capacity of the four spherical tanks significantly increases to 351 MWh, representing a 30.5% increase. This improvement can significantly increase the absorption of off-peak electricity and renewable energy sources such as wind and solar power, thereby significantly improving the economic benefits for enterprises by fully utilizing low-cost electricity and efficient energy conversion.

[0075] The foregoing descriptions are merely illustrative of certain exemplary embodiments of the present invention. Those skilled in the art can make various modifications to the embodiments without departing from their spirit and scope. Therefore, the above figures and descriptions are illustrative in nature and do not constitute a limitation on the scope of the claims. The present invention is not limited to the above embodiments. Any product derived by any person under its guidance, with a technical solution that is the same as or similar to this application, regardless of changes in shape or structure, is within the scope of protection.

Claims

1. A coupled system for electric heating steam storage, supply, and quality improvement, characterized in that, It includes an electrode steam boiler-spherical tank storage and supply system (1), a steam compressor system (2), and an external steam source; The steam outlet pipeline of the electrode steam boiler-spherical tank storage and supply system (1) is divided into three lines, which are connected to the steam compressor system (2): the first line is connected to the steam outlet pipeline of the steam compressor system (2), and the two are combined to form an external output pipeline to supply industrial steam; the second line and the third line are combined with the output pipeline of the external steam source to form a main pipe, which is connected to the steam inlet of the steam compressor system (2); The first pipeline is equipped with a compressor bypass electric gate valve (3), the second pipeline is equipped with a compressor inlet pressure reducing valve (4), the third pipeline is equipped with a compressor inlet direct-connect electric gate valve (5), and the connecting pipeline of the external steam source to the steam inlet pipeline of the steam compressor system (2) is equipped with an external steam source flow regulating valve (6). The electrode steam boiler-spherical tank storage and supply system (1) includes an electrode steam boiler (1.1), a high-pressure steam distribution cylinder (1.2), a spherical tank (1.3), a medium and low-pressure steam distribution cylinder (1.4), a steam electric heater (1.5), a demineralized water supply tank (1.6), a deaerator (1.7), a deaerator water supply pump (1.81), a spherical tank water supply pump (1.82), and a boiler feed water pump (1.83). The steam compressor system (2) includes a steam compressor (2.1), a compressor inlet de-cooling device (2.2), and a compressor outlet de-cooling device (2.3). The steam inlet of the steam compressor (2.1) is connected to the steam outlet of the compressor inlet de-cooling device (2.2), and the steam outlet of the steam compressor (2.1) is connected to the steam inlet of the compressor outlet de-cooling device (2.3).

2. The system according to claim 1, characterized in that, The first makeup water inlet of the demineralized water makeup water tank (1.6) is connected to the chemical demineralized water system, the second makeup water outlet is connected to the makeup water inlet of the deaerator makeup water pump (1.81), and the third makeup water outlet is connected to the first makeup water inlet of the spherical tank (1.3); the makeup water outlet of the deaerator makeup water pump (1.81) is connected to the first makeup water inlet of the deaerator (1.7), the second steam inlet of the deaerator (1.7) is connected to the fourth steam outlet of the medium and low pressure steam distribution cylinder (1.4), and the third feed water outlet of the deaerator (1.7) is connected to the feed water inlet of the boiler feed water pump (1.83); the feed water outlet of the boiler feed water pump (1.83) is connected to the feed water inlet of the electrode steam boiler (1.1), and the electrode steam boiler (1.1) includes a high-voltage electrode (1.10); The steam outlet of the electrode steam boiler (1.1) is connected to the first steam inlet of the high-pressure steam distributor (1.2); the second steam outlet of the high-pressure steam distributor (1.2) is connected to the second steam inlet of the medium-low pressure steam distributor (1.4), and a boiler direct supply pressure reducing valve (1.93) is installed on this pipeline; the third steam outlet of the high-pressure steam distributor (1.2) is connected to the second steam inlet of the spherical tank (1.3); The third steam outlet pipe of the spherical tank (1.3) is divided into two parallel pipes and then connected to a steam pipe, which is connected to the first steam inlet of the medium and low pressure steam distribution cylinder (1.4): the first pipe is equipped with a high and medium pressure section flash steam pressure reducing valve (1.91), and the second pipe is equipped with a medium and low pressure section flash steam pressure reducing valve (1.92); the third steam outlet of the medium and low pressure steam distribution cylinder (1.4) is connected to the steam inlet of the steam electric heater (1.5), and the steam outlet pipe of the steam electric heater (1.5) is the steam outlet pipe of the electrode steam boiler-spherical tank storage and supply system (1).

3. The system according to claim 1, characterized in that, The steam compressor (2.1) is equipped with a variable frequency speed control motor, and is also equipped with an anti-surge backflow pipeline and an anti-surge backflow valve, which are used to stabilize the working state through backflow regulation during surge conditions; The steam inlet pipe of the compressor inlet desuperheating device (2.2) is the steam inlet pipe of the steam compressor system (2), and the steam outlet pipe of the compressor outlet desuperheating device (2.3) is the steam outlet pipe of the steam compressor system (2). The steam compressor (2.1) stabilizes the outlet steam pressure through variable frequency speed control technology, controls the inlet steam superheat through the compressor inlet desuperheating device (2.2), and maintains a constant outlet steam temperature through the compressor outlet desuperheating device (2.3).

4. The system according to claim 1, characterized in that, The external steam source flow regulating valve (6) is used to regulate the steam supply of the external steam source and to control the ratio of the steam flow of the electrode steam boiler-spherical tank storage and supply system (1) at the inlet of the steam compressor (2.1) to that of the external steam source.

5. The system according to claim 1, characterized in that, The electrode steam boiler (1.1), high-pressure steam distributor (1.2), spherical tank (1.3), medium and low-pressure steam distributor (1.4), and deaerator (1.7) are all equipped with safety valves, which automatically open to release pressure when the pressure rises to the set pressure.

6. The system according to claim 1, characterized in that, At least one of the electrode steam boiler (1.1), spherical tank (1.3), steam electric heater (1.5), deaerator water supply pump (1.81), spherical tank water supply pump (1.82), boiler feed water pump (1.83), and steam compressor (2.1) can be configured in parallel with multiple units according to relevant standards, specifications, and usage requirements.

7. A method for operating and controlling an electrically heated steam storage, supply, and quality improvement coupled system, characterized in that, The method, based on the coupling system described in any one of claims 1-6, achieves efficient industrial steam supply through the following steps: Based on the electricity price period, steam demand parameters and system thermal storage status, selective switching is allowed between "external steam source independent steam supply mode", "electrode steam boiler-spherical tank storage and supply system (1) independent steam supply mode" and "external steam source and electrode steam boiler-spherical tank storage and supply system (1) joint steam supply mode". The mode switching is achieved by regulating the opening and closing states of the compressor bypass electric gate valve (3), compressor inlet pressure reducing valve (4), compressor inlet direct-connect electric gate valve (5) and external steam source flow regulating valve (6), in conjunction with the start-up and shutdown and parameter adjustment of the electrode steam boiler (1.1) and steam compressor (2.1), so as to realize the efficient consumption of off-peak electricity or new energy power, optimize operating costs and ensure a stable supply of industrial steam.

8. The method according to claim 7, characterized in that, External steam source independent steam supply mode: Close the compressor bypass electric gate valve (3) and compressor inlet pressure reducing valve (4), and open the compressor inlet direct electric gate valve (5); the electrode steam boiler-spherical tank storage and supply system (1) stops operating, and only the external steam source steam supply is regulated by the external steam source flow regulating valve (6). The steam is upgraded by passing through the compressor inlet desuperheating device (2.2), steam compressor (2.1), and compressor outlet desuperheating device (2.3) before being supplied to the outside. Electrode Steam Boiler-Spherical Tank Storage and Supply System (1) Independent Steam Supply Mode: Includes at least one operating mode: ① Direct boiler supply via compressor bypass: The electrode steam boiler (1.1) produces high-pressure steam, which is reduced in pressure by the high-pressure steam distribution cylinder (1.2) and the direct boiler supply pressure reducing valve (1.93), and then heated by the medium and low pressure steam distribution cylinder (1.4) and the steam electric heater (1.5). The compressor bypass electric gate valve (3) is then opened to connect to the compressor system outlet pipeline for external steam supply; ② Spherical tank flash steam via compressor bypass: The high-pressure saturated water in the spherical tank (1.3) is flashed through the high and medium pressure sections. The steam pressure reducing valve (1.91) flashes into medium-pressure steam, which is then heated by the medium-low pressure steam distribution cylinder (1.4) and the steam electric heater (1.5). The compressor bypass electric gate valve (3) is then opened to supply steam to the outside. ③ The spherical tank flashes into steam and supplies steam to the compressor body: The medium-pressure saturated water in the spherical tank (1.3) flashes into low-pressure steam through the medium-low pressure section flash pressure reducing valve (1.92). After being heated by the steam electric heater (1.5), the compressor inlet direct electric gate valve (5) is opened. The steam is then heated by the compressor inlet desuperheating device (2.2) and the steam compressor (2.1) in sequence to supply steam to the outside. Combined steam supply mode: The external steam source provides low-pressure steam through the external steam source flow regulating valve (6), which is combined with the steam output from the electrode steam boiler-spherical tank storage and supply system (1) through the compressor inlet pressure reducing valve (4) or the compressor inlet direct electric gate valve (5) in the compressor system inlet main pipe. The mixed steam is upgraded by the steam compressor (2.1) and then supplied to the outside. The flow ratio is controlled by the external steam source flow regulating valve (6).

9. The method according to claim 7, characterized in that, During off-peak electricity price periods: the electrode steam boiler (1.1) is put into operation, and the operation mode of "direct boiler supply via compressor bypass steam supply" and the operation mode of electrode steam boiler (1.1) storing heat in spherical tank (1.3) are started at the same time; after the pressure of spherical tank (1.3) rises to the high pressure parameter (PH), the heat storage process is stopped, and only the direct boiler supply mode is kept running to give priority to consuming off-peak electricity or new energy power. During peak electricity price periods: shut down the electrode steam boiler (1.1) and switch to the "spherical tank flash steam supply via compressor bypass" or "spherical tank flash steam supply via compressor body" mode to release the heat of the spherical tank (1.3); when the pressure of the spherical tank (1.3) drops to the medium pressure parameter (PM) or low pressure parameter (PL), adjust the steam supply path by switching the valve until the pressure of the spherical tank (1.3) drops to the low pressure parameter (PL), and then switch back to the "external steam source independent steam supply mode".

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