Vehicle-mounted mobile heat storage device

Abstract

This invention discloses a mobile heat storage device that can utilize off-peak electricity and industrial waste heat: off-peak electricity is supplied via electric heating elements, while waste heat is supplied as steam or hot water to the mobile heat storage vehicle; the heat storage vehicle body is equipped with a heat accumulator to store thermal energy, and the heat storage material is placed inside the heat accumulator to store energy; expansion pipes are installed on both sides of the top of the heat accumulator; the electric heating element installed at the top is directly connected to the bottom of the heat accumulator; a cylindrical trough isolated from the heat accumulator is installed at the top near the tail of the heat accumulator, and a circulation pump is placed in the trough; the circulation pump draws liquid from the fluid collection pipe and pumps it into the shell-and-tube heat exchanger, and after heat exchange, the fluid enters the fluid distributor at the bottom, where it exchanges heat with the heat storage material again; by using a mobile heat accumulator to supply heat energy using off-peak electricity or waste heat, the traditional pipeline heating method is changed, which can smooth out peak and valley loads in the heating system and achieve energy conservation and emission reduction by utilizing waste heat resources.

Description

Technical Field

[0001] This invention relates to a mobile, vehicle-mounted thermal storage device for energy storage. Background Technology

[0002] Industrial production processes generate significant amounts of waste heat that are wasted without being utilized. Simultaneously, many users rely on their own gas-fired or oil-fired boilers to meet their production heat needs, resulting in incalculable energy losses and substantial environmental pollution. This situation no longer aligns with the government's requirements for production units, especially given the increasing emphasis on energy conservation, emission reduction, and environmental protection. For example, finding a suitable outlet for waste heat steam generated by some factories has become an urgent need for increased profits; similarly, power plants face challenges in increasing revenue due to imbalances in electricity supply and demand during the day and night, particularly during peak winter heating seasons and in utilizing surplus summer heat. A feasible solution would be to utilize waste heat or off-peak electricity from other areas without pipeline transportation to supplement the winter peak load and to relocate and utilize surplus summer heat. Summary of the Invention

[0003] The technical problem solved by this invention is how to remove and utilize waste heat, organically connecting it with users who need heat energy, and supplying steam or hot water to users. This bridges the gap in waste heat resource recovery and utilization, changes the traditional energy supply method, achieves peak shaving and valley filling for electric and gas heating systems, realizes the purpose of utilizing waste heat resources, and thus reduces pollution emissions.

[0004] This invention provides a mobile vehicle-mounted thermal energy storage device. The technical solution involves using off-peak electricity for heating via electric heating elements, while waste heat is transferred to the mobile thermal energy storage vehicle as steam or hot water via a shell-and-tube heat exchanger. A thermal accumulator for storing thermal energy is installed in the main body of the thermal energy storage vehicle. The accumulator is supported at a certain distance from the vehicle body. Insulation material is filled between the external casing of the thermal energy storage vehicle and the accumulator, as well as between the vehicle body and the accumulator, to prevent heat loss. Thermal storage materials are placed inside the accumulator to store energy. These materials include solid ceramic thermal storage balls, thermal storage balls encapsulated with phase change materials, and organic materials that have a significant density difference with the circulating fluid and are non-reactive and immiscible within the operating temperature range. Expansion pipes are installed on both sides of the top of the accumulator to absorb the high-temperature expansion portion of the fluid. An electric heating element is located in the middle of the top, directly connected to the bottom of the accumulator. A cylindrical groove is located at the middle of the top tail, and a circulation pump is installed inside the groove. To facilitate installation and save space, the cylindrical groove is partially embedded within the heat accumulator, but its bottom is sealed and isolated from the fluid inside the accumulator. A fluid collection pipe passes through the cylindrical groove and connects to the inlet of the circulation pump. The outlet of the circulation pump is connected to another pipe passing through the cylindrical groove, which in turn connects to the inner tube cavity of the shell-and-tube heat exchanger. The shell-and-tube heat exchanger is serpentine and vertically positioned, with its straight pipe sections intersecting with the electric heating tubes. The other end of the inner tube cavity of the shell-and-tube heat exchanger communicates with the fluid distributor at the bottom of the heat accumulator. The outer shell inlet and outlet pipes of the shell-and-tube heat exchanger pass through the bottom of the heat accumulator and extend from the side or rear of the heat accumulator vehicle, connecting to the inlet and outlet of the external fluid. Attached Figure Description

[0005] Appendix Figure 1 The components of the vehicle-mounted thermal storage vehicle are shown in the diagram on the right. The diagram is labeled as follows: 101-Temperature accumulator; 102-Temperature storage material; 103-Circulating fluid; 104-Expansion pipe; 105-Electric heating element; 106-Cylindrical tank; 107-Circulation pump; 108-Fluid collector main pipe; 109-Fluid collector branch pipe; 110-Shell-tube heat exchanger; 111-Fluid distributor main pipe; 112-Fluid distributor branch pipe; 113-Hot fluid inlet; 114-Hot fluid outlet; 115-Temperature accumulator support; 116-Temperature storage vehicle body; 117-Insulation material.

[0006] Appendix Figure 2 The main view shows the components of the vehicle-mounted thermal storage vehicle, labeled as follows: 201-Temperature accumulator; 202-Temperature storage material; 203-Circulating fluid; 204-Expansion pipe; 205-Electric heating element; 206-Cylindrical tank; 207-Circulating pump; 208-Fluid collector main pipe; 209-Fluid collector branch pipe; 210-Shell-tube heat exchanger; 211-Fluid distributor main pipe; 212-Fluid distributor branch pipe; 213-Hot fluid inlet and outlet; 215-Temperature accumulator support; 216-Temperature storage vehicle body; 217-Insulation material.

[0007] Appendix Figure 3 The diagram shows the components of the vehicle-mounted thermal storage vehicle in a top view. The labels are: 301-Temperature accumulator; 302-Temperature storage material; 304-Expansion pipe; 305-Electric heating element; 306-Cylindrical trough; 307-Circulation pump; 308-Fluid collector main pipe / fluid distributor main pipe; 309-Fluid collector branch pipe / fluid distributor branch pipe; 310-Shell-tube heat exchanger; 316-Temperature storage vehicle body; 317-Insulation material.

[0008] Appendix Figure 4 This is a schematic diagram of a shell-and-tube heat exchanger. The diagram is labeled as follows: 401 - outer shell of the shell-and-tube heat exchanger; 402 - inner tube of the shell-and-tube heat exchanger; 403 - inlet of the outer shell of the shell-and-tube heat exchanger; 404 - outlet of the outer shell of the shell-and-tube heat exchanger; 405 - inlet of circulating fluid; 406 - outlet of circulating fluid.

[0009] Appendix Figure 5 This is a schematic diagram of a fluid distributor. The diagram is labeled as follows: 501 - Fluid distributor main pipe; 502 - Fluid distributor branch pipe; 503 - Fluid distributor branch pipe opening.

[0010] Appendix Figure 6 This is a schematic diagram of a fluid collector. The diagram is labeled as follows: 601 - Fluid collector main pipe; 602 - Fluid collector branch pipe; 603 - Fluid collector branch pipe opening. Detailed Implementation

[0011] First, the present invention will be described in the case of phase change heat storage where the heat storage material is in direct contact with the circulating fluid, focusing on the heat storage and heat release processes.

[0012] Off-peak electricity thermal storage: Due to the direct contact between the thermal storage material and the circulating fluid in a phase change thermal storage process, the density of the thermal storage material is higher than that of the circulating fluid. Therefore, there is a clear stratification between the circulating fluid and the thermal storage material. The thermal storage material, having completed heat release, settles in solid form at the bottom of the thermal storage tank. Numerous micropores exist between the thermal storage particles or crystals, and these micropores are filled by the circulating fluid, while most of the circulating fluid floats on top of the thermal storage material. Off-peak electricity is converted into heat energy by electric heating elements. The heating elements transfer energy to the surrounding circulating fluid and thermal storage material, causing the surrounding thermal storage material to melt first, resulting in the expansion of the micropores around the heating elements. Under the action of a circulating pump, the circulating fluid is collected by a fluid collector and pumped to a shell-and-tube heat exchanger for heat exchange before entering the bottom of the thermal storage tank. A fluid distributor forces the fluid to flow upwards, achieving internal circulation. This forces the hot fluid carrying heat to exchange heat with the surrounding cold fluid and thermal storage material. Heat gradually diffuses to the surrounding fluid and thermal storage material, and the system gradually heats up until the thermal storage material undergoes a complete phase change, completing the thermal storage process.

[0013] Off-peak electricity heat release: Start the circulation pump. Under suction, the circulating fluid flows into the fluid collector branch pipe through the opening at the top of the fluid collector branch pipe and gathers into the fluid collector main pipe before entering the circulation pump. It is pumped into the inner tube of the shell-and-tube heat exchanger, heating the fluid entering the outer shell cavity of the shell-and-tube heat exchanger. The temperature of the circulating fluid decreases, and after exiting the shell-and-tube heat exchanger, it enters the fluid distributor main pipe at the bottom of the heat accumulator. Through the openings of the fluid distributor branch pipe, the fluid is forced to flow upward, exchanging heat with the surrounding circulating fluid and heat storage material. Gradually, it reaches the top of the heat accumulator, where the temperature rises, and it re-enters the fluid collector to participate in the next heat exchange cycle until the heat storage material undergoes a complete phase change, transforming from liquid to solid, and the heat release is completed.

[0014] Waste heat storage: The fluid carrying waste heat enters the outer shell cavity of the inner shell heat exchanger of the heat accumulator. On one hand, it exchanges heat with the circulating fluid outside the shell heat exchanger, increasing the micropores between the surrounding solid heat storage materials and promoting the flow of internal circulation. On the other hand, the fluid carrying waste heat exchanges heat with the circulating fluid inside the shell heat exchanger, releasing heat and flowing out of the heat accumulator from the outer shell cavity. Meanwhile, the circulating fluid inside the heat accumulator, under the action of the circulating pump, causes the fluid absorbing heat around the shell heat exchanger to heat up and gradually diffuse. Furthermore, through forced circulation, the circulating fluid entering the inner shell heat exchanger absorbs heat and diffuses it through the fluid distributor at the bottom of the heat accumulator to the area around the heat storage material inside the heat accumulator. Through heat exchange, the temperature of the heat storage material rises until a complete phase change occurs, and heat storage is completed.

[0015] Waste heat release: The user fluid enters the outer shell cavity of the inner shell heat exchanger of the heat accumulator from the external fluid inlet. On the one hand, it absorbs the energy of the heat storage material in the heat accumulator cavity, and on the other hand, it exchanges heat with the circulating fluid entering the inner shell heat exchanger. After the user fluid is heated, it flows out from the outer shell of the heat exchanger. The circulating fluid in the inner shell heat exchanger is cooled down and then flows out from the inner shell of the heat exchanger under the action of the circulating pump. It enters the fluid distributor at the bottom of the heat accumulator and is forced to flow upward to exchange heat with the heat storage material. After the temperature rises, it enters the circulating pump from the fluid collector at the top of the heat accumulator to participate in heat exchange again until the heat storage material in the heat accumulator has released heat and changed from liquid to solid.

[0016] The embodiments of the present invention will now be described in conjunction with the accompanying drawings: The device of this invention is suitable for storing heat during off-peak hours as well as for storing heat using industrial waste heat. It transfers and utilizes heat energy via a vehicle-mounted system. Off-peak electricity is heated by electric heating element 105, while waste heat is transferred to the mobile heat storage vehicle in the form of steam or hot water via shell-and-tube heat exchanger 110.

[0017] Reference Appendix Figure 1A heat storage accumulator 101 for storing thermal energy is installed in the heat storage compartment 116. The heat storage accumulator 101 is maintained at a certain distance from the vehicle body via a heat storage support 115. Insulation material 117 is filled between the heat storage compartment 116 and the heat storage accumulator 101, and between the vehicle body and the heat storage accumulator 101, to prevent heat loss. A heat storage substance 102 is placed inside the heat storage accumulator 101 to store energy. The heat storage substance 102 includes solid ceramic heat storage balls, heat storage balls encapsulated with inorganic / organic phase change materials, and organic substances that have a significant density difference with the circulating fluid 103 and do not react or dissolve within the operating temperature range. The suitable circulating fluid 103 has the characteristics of high temperature resistance, low vapor pressure, low viscosity, and stability and safety, and can include water, molten salt, xylene ether, hydrogenated terphenyl, silicone oil, biphenyl-diphenyl ether mixture, and ethylene glycol aqueous solution.

[0018] Expansion tubes 104 are installed on both sides of the top of the heat accumulator 101. The bottom of the expansion tubes 104 is higher than the top of the heat accumulator 101 to absorb the high-temperature expansion of the fluid. An electric heating element 105 is located in the middle of the top of the heat accumulator 101 and is directly connected to the bottom of the heat accumulator 101. A cylindrical groove 106 is located in the middle of the top end. A circulation pump 107 is installed in the cylindrical groove 106. To facilitate installation and save space, the cylindrical groove 106 is partially embedded in the heat accumulator 101, but the bottom of the cylindrical groove 106 is sealed and isolated from the circulating fluid 103 inside the heat accumulator 101. A fluid collection pipe passes through the cylindrical groove 106 and connects to the inlet of the circulation pump 107. The outlet of the circulation pump 107 is connected to another pipe passing through the cylindrical groove 106. This pipe is connected to the cavity of the inner tube 402 of the shell-and-tube heat exchanger.

[0019] The outlet end of the inner tube 402 of the shell-and-tube heat exchanger is connected to the fluid distributor at the bottom of the heat accumulator 101. First, the circulating fluid 103 enters the main fluid distributor 111 and then, through the openings on the branch pipes 112, forces the surrounding fluid upwards. The angle α between the branch pipe openings 503 and the horizontal ranges from 15 to 90 degrees, with symmetrical openings on both sides. Each opening is between 2 and 10 millimeters in size, and the spacing between the openings is between 20 and 200 millimeters. The upward-moving circulating fluid 103 exchanges heat with the heat storage material 102, gradually increasing in temperature until it reaches the top of the heat accumulator 101, enters the fluid collector branch pipe 602, and converges into the main fluid collector 601. The openings 603 in the fluid collector branch pipe are located at the top to prevent solid particles from entering and clogging the pipes. The size of the openings 603 in the fluid collector branch pipe is between 2 and 10 millimeters, and the spacing between the openings is between 20 and 200 millimeters. The circulating fluid 103 is drawn from the fluid collector main pipe 601 into the inner pipe 402 of the shell-and-tube heat exchanger by the circulating pump 107 inside the cylindrical tank 106. After heat exchange, it enters the fluid distributor main pipe 501 at the bottom of the accumulator 101 for the next heat exchange cycle. The outer shell inlet 403 and outer shell outlet 404 of the shell-and-tube heat exchanger pass through the bottom of the accumulator 101 and are led out from the side or rear of the energy storage vehicle to connect with the inlet and outlet of the external fluid.

[0020] Shell-and-tube heat exchanger 110 as attached Figure 4 As shown, the structure is a serpentine structure, vertically placed, and cross-installed with the electric heating element 105. This facilitates the heating and melting of the surrounding material through the electric heating element 105 or the outer wall of the outer sleeve 401 of the shell-and-tube heat exchanger during the heat storage process of the heat storage material 102. This expands the micropores, accelerates fluid circulation, improves heat storage efficiency, and reduces the heat storage completion time. The main material of the shell-and-tube heat exchanger 110 is stainless steel. The outer sleeve 401 of the shell-and-tube heat exchanger can be selected as a seamless stainless steel tube or a stainless steel corrugated tube, depending on the pressure resistance requirements. The use of a stainless steel corrugated tube results in better heat exchange performance. The circulating fluid 103 enters the inner tube 402 of the shell-and-tube heat exchanger, while the external fluid enters the outer sleeve 401. This is mainly because the external fluid can simultaneously exchange heat with both the fluid outside the shell-and-tube heat exchanger 110 and the fluid in the inner tube 402 of the shell-and-tube heat exchanger, increasing the heat exchange area and improving the effect.

Claims

1. A vehicle-mounted mobile heat storage device, characterized in that: The heat storage tank contains heat storage material to store energy, and expansion tubes are installed on both sides of the top of the heat storage tank; the electric heating element is located in the middle of the top of the heat storage tank and is directly connected to the bottom of the heat storage tank; the cylindrical groove is located in the middle of the tail end of the top of the heat storage tank, and the cylindrical groove is partially embedded in the heat storage tank, with the bottom of the cylindrical groove sealed and isolated from the circulating fluid inside the heat storage tank. A circulating pump is installed inside the cylindrical groove; a fluid collector is also installed on the heat accumulator, and the pipe of the fluid collector passes through the cylindrical groove and connects to the inlet of the circulating pump; the outlet of the circulating pump is connected to another pipe passing through the cylindrical groove, which is connected to the inner tube cavity of the shell-and-tube heat exchanger; the shell-and-tube heat exchanger is serpentine and installed vertically, with its straight pipe section intersecting with the electric heating tube; the other end of the inner tube cavity of the shell-and-tube heat exchanger is connected to the fluid distributor at the bottom of the heat accumulator; the outer shell inlet and outer shell outlet pipes of the shell-and-tube heat exchanger pass through the bottom of the heat accumulator and are led out from the side or rear of the heat accumulator vehicle to connect to the inlet and outlet of the external fluid; The heat storage materials include solid ceramic heat storage balls, heat storage balls encapsulating inorganic / organic phase change materials, and organic materials that have a significant density difference with the circulating fluid and do not react or dissolve within the operating temperature range; The fluid inside the outer shell cavity of the shell-and-tube heat exchanger is the external fluid, and the fluid inside the inner tube of the shell-and-tube heat exchanger is the circulating fluid inside the heat accumulator. The circulating fluid includes water, molten salt, xylyl ether, hydrogenated terphenyl, silicone oil, a mixture of biphenyl and biphenyl ether, and an aqueous solution of ethylene glycol; The shell-and-tube heat exchanger is made of stainless steel, and its outer shell is made of seamless stainless steel tube or stainless steel corrugated tube.

2. The vehicle-mounted mobile heat storage device as described in claim 1, wherein the main fluid collector is connected to a branch fluid collector at regular intervals, and the top of the branch fluid collector has holes with a diameter of 2 mm to 10 mm at regular intervals to collect fluid.

3. The vehicle-mounted mobile heat storage device as described in claim 1, wherein the main fluid distributor is connected to a branch fluid distributor at intervals, and the branch fluid distributor has symmetrical holes of 2 mm to 10 mm in diameter at intervals to distribute the fluid, and the angle between the holes and the horizontal ranges from 15 degrees to 90 degrees.

4. In the vehicle-mounted mobile heat storage device as described in claim 1, the bottom of the expansion tube is higher than the top of the heat storage device.

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