Electrode heating energy storage system
The electrode heater generates heat in the non-aqueous liquid and uses a circulating fan to heat the heat storage medium, which solves the problem of high cost of electric heaters, improves the thermal energy conversion and storage efficiency, and achieves low-cost electrical energy conversion and storage.
Patent Information
- Application Number
- CN202310867806.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2023-07-16
- Publication Date
- 2025-01-17
AI Technical Summary
Among the existing thermal energy storage technologies, electric heaters are expensive, especially molten salt heat storage and solid thermal electric heaters, and the thermal conductivity of the solid heat storage medium is low, resulting in low efficiency of converting electrical energy into thermal energy.
The electrode heater is used to heat the electrical energy through the electrode as a resistive resistance in the non-aqueous liquid. The gas medium is directly heated by the non-aqueous liquid with high heat transfer performance, and the high-temperature gas medium is heated through the circulation fan and the heat storage device to reduce the cost of the high-temperature gas medium. Costs of electric heaters and heat storage media.
The rate and efficiency of electric heating gas are improved, the cost of converting electricity into gas thermal energy is reduced, and the heat is effectively stored through cheap heat storage medium, achieving low-cost conversion and storage of electrical energy.
Smart Images
Figure CN119321699A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to electric heating energy storage utilization, and in particular to an electrode heating energy storage system. Background Art
[0002] With the huge consumption of traditional fossil energy, people are facing increasingly severe energy and environmental problems. The new energy technology revolution should start from improving energy utilization efficiency and optimizing energy consumption structure. Increasing the proportion of non-fossil energy, especially renewable energy, is of great significance to future energy and environment. Renewable energy has been regarded as the strategic commanding height of the new generation of energy technology. Renewable energy includes hydropower, wind power, solar energy, biomass energy, geothermal energy and ocean energy.
[0003] As my country's energy security and carbon emission reduction requirements gradually increase, clean and low-carbon photovoltaic and wind power generation capacity continues to grow, and the power system has entered an era of high-proportion renewable energy grid connection. Achieving carbon peak and carbon neutrality and striving to build a clean, low-carbon, safe and efficient energy system are major decisions and deployments made by the country. The introduction of the "dual carbon" policy has accelerated the transformation of power supply energy to renewable energy. Renewable energy (such as wind power and solar energy) power generation is intermittent and unstable, and cannot continuously and stably output electricity; the strong volatility and randomness of high-proportion photovoltaic and wind power output will put forward higher requirements for the flexibility of the power system. Its grid connection through power electronic devices brings problems such as low system inertia and safety and stability. The large-scale consumption of new energy has become a difficult point that needs to be broken through; and from the electricity consumption side, there are peak and trough periods, and electricity demand fluctuates. For the energy consumption of a single enterprise (including water, electricity, etc.), there is also a problem of time and space mismatch between the supply side and the demand side.
[0004] Energy storage technology can increase the flexibility of electricity and water vapor allocation, improve power quality, and enhance grid stability. It is an important means to solve the contradiction between supply and demand in the new power system. Energy storage is an important technology and basic equipment to support the new power system. Thermal energy storage is an important type of new energy storage technology. It has the characteristics of low heat storage price, large scale, long storage time, safety, reliability, flexibility and diversity, and has huge development potential.
[0005] Common forms of thermal energy storage include molten salt heat storage and solid heat storage represented by magnesium bricks. In terms of peak load regulation of the power grid and the absorption of fluctuating new energy, fluctuating electricity or cheap valley electricity is converted into thermal energy and stored in molten salt or solid heat storage media. When needed, the stored heat energy can generate high-temperature water vapor for heating or power generation, and high-temperature air can also be generated for drying and utilization. At present, the conventional method of converting electricity into heat uses resistive electric heaters to directly heat molten salt or solid heat storage media. The cost of solid heat storage media is generally lower than that of molten salt, but the thermal conductivity of solid heat storage media is low, and a large amount of electric heating materials are required to effectively transfer the heat energy converted from electricity to the solid medium; molten salt is a liquid, and its heat transfer performance is better than that of solid materials, so the molten salt heater is relatively small in size and low in cost. Summary of the invention
[0006] In view of the current problems of thermal energy storage, especially the relatively high cost of molten salt heat storage in electric heating heat storage technology and the high cost of solid heat storage electric heaters, the present invention proposes a new type of electrode heating energy storage system to effectively reduce the cost of electric heaters and heat storage media. The specific scheme of the present invention is as follows: An electrode heating energy storage system, characterized in that it includes an electrode heater outer shell, an electrode heater inner cylinder, an electrode, and a blower, wherein the electrode heater inner cylinder is located inside the electrode heater outer shell, the upper opening of the electrode heater inner cylinder is connected to the interior of the electrode heater shell, the electrode heater inner cylinder is filled with a non-aqueous liquid, the electrode is located inside the electrode heater inner cylinder and is in contact with the non-aqueous liquid, the blower has a gas inlet and an outlet, and the gas outlet of the blower is located in the non-aqueous liquid inside the electrode heater inner cylinder.
[0007] The electrodes, under the action of voltage, use the non-aqueous liquid as a resistor to directly generate heat, thereby heating the non-aqueous liquid. The gas medium flowing out of the air distributor outlet directly contacts the non-aqueous liquid, and the gas medium is directly heated by the non-aqueous liquid.
[0008] Furthermore, a heat storage device and a circulating fan are added, the gas outlet of the outer shell of the electrode heater is connected to the inlet of the heat storage device, the outlet of the heat storage device is connected to the inlet of the circulating fan, and the outlet of the circulating fan is connected to the gas inlet of the air distributor. The high-temperature gas medium flows out from the gas outlet of the outer shell of the electrode heater, enters the heat storage device, heats the heat storage medium in the heat storage device, and the cooled gas medium flows out from the heat storage device, enters the circulating fan, and then re-enters the inlet of the air distributor to start a new heating cycle.
[0009] Preferably, the heat storage device is filled with a heat storage medium, and the heat storage medium has an internal flow channel. When the gas medium flows through the internal flow channel, the heat storage medium is heated, and the gas temperature is reduced. The heat storage medium is one or more of honeycomb ceramics, foam ceramics, temperature-resistant bricks, foam metals, wire mesh, stacked gravel, phase change materials, and thermochemical heat storage materials.
[0010] The gas medium is any one or more of air, hydrogen, carbon dioxide, nitrogen, and helium. The non-aqueous liquid is molten salt, liquid metal, or heat transfer oil.
[0011] The present invention utilizes an electrode heater to heat a non-aqueous liquid, and then directly heats the gas through the non-aqueous liquid, thereby reducing the cost and structure of the heater and improving the reliability of the electric heating process. While the electric heater converts electrical energy into thermal energy, the high heat transfer performance of the non-aqueous liquid efficiently and quickly converts thermal energy into gas thermal energy, and at the same time, the high-temperature gas enters the heat storage device to heat the cheap heat storage medium. Through the above system, electrical energy is finally converted into thermal energy and stored in the heat storage medium.
[0012] On the one hand, the present invention increases the rate of electrically heating gas and reduces the cost of converting electricity into gas thermal energy; on the other hand, the gas medium can directly contact and transfer heat with a variety of cheap heat storage media without reacting, thereby effectively storing heat on a large scale at low cost. BRIEF DESCRIPTION OF THE DRAWINGS
[0013] Figure 1 is a schematic diagram of specific embodiment 1; Figure 2 is a schematic diagram of specific embodiment 2; In the figure: 1-electrode; 2-electrode heater inner cylinder; 3-electrode heater outer shell; 4-non-aqueous liquid; 5-air distributor; 6-circulating fan; 7-heat storage device. Implementation Example 1
[0014] The present invention proposes an electrode heating energy storage system, such as Figure 1 As shown, it includes an electrode 1, an electrode heater inner cylinder 2, an electrode heater outer shell 3, a non-aqueous liquid 4, and a blower 5. The electrode heater inner cylinder 2 is located inside the electrode heater outer shell 3. The upper part of the electrode heater inner cylinder 2 is open and communicated with the inside of the electrode heater outer shell 3. The electrode heater inner cylinder 2 is filled with the non-aqueous liquid 4. The electrode 1 is located inside the electrode heater inner cylinder 2 and contacts with the non-aqueous liquid 4. The blower 5 has a gas inlet and an outlet. The gas outlet of the blower 5 is located in the non-aqueous liquid 4 inside the electrode heater inner cylinder 2, that is, the gas outlet of the blower 5 is immersed in the non-aqueous liquid 4 in the electrode heater inner cylinder 2.
[0015] Preferably, the non-aqueous liquid 4 in this embodiment is molten salt, and the gas medium is air. When the system is working, the electrode 1 is partially immersed in the molten salt. Under the action of voltage, the molten salt acts as a resistor to conduct electricity and generate heat, thereby heating the molten salt itself, and the temperature can be as high as 550°C. The air enters from the inlet of the air distributor 5, flows out from the outlet of the air distributor 5, and directly contacts with the high-temperature molten salt, thereby heating the air directly. Molten salt has a large heat capacity, can store a certain amount of heat energy, and stabilize the heating temperature of the air. The heated air flows out from the upper opening of the electrode heater inner tube 2, enters the interior of the electrode heater outer shell 3, and finally flows out through the gas outlet of the electrode heater outer shell 3. The electrode heater outer shell 3 is insulated from the electrode heater inner tube 2, so the electrode heater outer shell 3 is not charged.
[0016] The embodiment of the present invention utilizes the electrode 1 and the molten salt medium itself to efficiently convert electrical energy into thermal energy, with a simple and reliable structure and low cost. At the same time, the molten salt is in direct contact with the air, with a fast heat transfer rate and a small heat transfer temperature difference. Through this system, electrical energy is ultimately converted into thermal energy of air safely, reliably and at low cost, generating high-temperature air. Example 2
[0017] like Figure 2 As shown, a circulating fan 6 and a heat storage device 7 are additionally provided on the basis of Example 1, the gas outlet of the electrode heater outer shell 3 is connected to the inlet of the heat storage device 7, the outlet of the heat storage device 7 is connected to the inlet of the circulating fan 6, and the outlet of the circulating fan 6 is connected to the inlet of the air distributor 5.
[0018] The air from the outlet of the air distributor 5 directly contacts with the high-temperature molten salt for heating, and then enters the heat storage device 7. The high-temperature air heats the heat storage medium inside the heat storage device. The air with a lowered temperature flows out from the outlet of the heat storage device 7, and then re-enters the air distributor 5 through the circulation fan 6. Through the above cycle, the heat energy converted from electrical energy is continuously stored in the heat storage device 7.
[0019] The heat storage medium filled in the heat storage device 7 is one or more of honeycomb ceramics, foam ceramics, temperature-resistant bricks, foam metals, wire mesh, stacked gravel, phase change materials, and thermochemical heat storage materials.
[0020] In summary, in this embodiment, the molten salt is directly heated as a resistor by utilizing the voltage applied to the electrode 1, and the heated molten salt directly contacts the air medium, thereby heating the air, making full use of the rapid heat transfer capacity of the molten salt medium, simplifying the heater structure, reducing the cost of converting electricity into thermal energy, and then using the hot air to store the heat in a cheap heat storage medium.
Claims
1. An electrode heating energy storage system, characterized in that It includes an electrode heater outer shell, an electrode heater inner cylinder, an electrode, and an air distributor. The electrode heater inner cylinder is located inside the electrode heater outer shell, the upper opening of the electrode heater inner cylinder is connected to the inside of the electrode heater shell, the electrode heater inner cylinder is filled with non-aqueous liquid, the electrode is located in the electrode heater inner cylinder and contacts with the non-aqueous liquid, the air distributor has a gas inlet and an outlet, and the gas outlet of the air distributor is located in the non-aqueous liquid inside the electrode heater inner cylinder.
2. An electrode heating energy storage system according to claim 1, characterized in that It includes a heat storage device and a circulating fan. The gas outlet of the outer shell of the electrode heater is connected to the inlet of the heat storage device, the outlet of the heat storage device is connected to the inlet of the circulating fan, and the outlet of the circulating fan is connected to the gas inlet of the air distributor.
3. An electrode heating energy storage system according to claim 1 or 2, characterized in that Under the action of voltage, the electrodes use the non-aqueous liquid as a resistor to directly generate heat, thereby heating the non-aqueous liquid.
4. An electrode heating energy storage system according to claim 1 or 2, characterized in that The gas medium flowing out from the outlet of the air distributor is in direct contact with the non-aqueous liquid, and the gas medium is directly heated by the non-aqueous liquid.
5. An electrode heating energy storage system according to claim 2, characterized in that The heat storage device is filled with a heat storage medium, and the heat storage medium has an internal flow channel. When the gas medium flows through the internal flow channel, the heat storage medium is heated, and the temperature of the gas is reduced.
6. An electrode heating energy storage system according to claim 5, characterized in that The heat storage medium is one or more of honeycomb ceramics, foam ceramics, temperature-resistant bricks, foam metals, wire mesh, stacked gravel, phase change materials, and thermochemical heat storage materials.
7. An electrode heating energy storage system according to claim 1 or 2, characterized in that The gas medium is any one or more of air, hydrogen, carbon dioxide, nitrogen and helium.
8. An electrode heating energy storage system according to claim 1 or 2, characterized in that The non-aqueous liquid is molten salt, liquid metal, or heat transfer oil.