Oil storage tank temperature maintaining system with built-in phase change heat storage body

Abstract

An oil storage tank temperature maintaining system with a built-in phase change heat storage body relates to the technical field of new energy and comprises an oil storage tank, a solar heat collection unit, a photovoltaic power generation unit, a waste heat utilization unit, an intelligent temperature control unit and an electric power storage unit. The oil storage tank is connected with the solar heat collection unit through a backflow pipeline. The photovoltaic power generation unit is connected with the electric energy switching control device, the electric energy switching control device is connected with the power storage unit and the waste heat utilization unit, a power supply line of the power storage unit is connected with the oil storage tank, the waste heat utilization unit is connected with the oil storage tank through a heat supply pipeline, and the oil storage tank is connected with the waste heat utilization unit through a backflow pipeline. And the electric energy switching control device is connected with a power grid. According to the oil storage tank temperature maintaining system with the built-in phase change heat storage body, an original phase change oil storage tank and an oil storage tank are combined, heat exchange between crude oil and the outside is reduced, and the temperature maintaining duration of the crude oil is greatly prolonged through the passive heat supply mode.

Description

Technical Field

[0001] The present invention relates to the field of new energy technology, and in particular to an oil storage tank temperature maintenance system containing a built-in phase change heat storage body. Background Art

[0002] Oil is the lifeblood of industry, supporting the booming development of transportation, aerospace, and the modern automotive industry. It is also a key raw material for chemical products such as plastics, fabrics, and synthetic rubber. Due to the high pour point and high viscosity of my country's crude oil, in cold winter regions, the heat exchange between the crude oil in storage tanks and the outside world causes the crude oil temperature to drop. Without heating and temperature control, this can easily lead to crude oil gelling accidents, seriously impacting the safe operation of the storage tanks.

[0003] Oil storage tanks, the reservoirs of the oilfield production chain, maintain a critical temperature during operation, ensuring crude oil fluidity and production continuity. Currently, most temperature maintenance methods rely on traditional gas / oil heating, which is associated with high gas consumption and carbon emissions. Therefore, upgrading tank temperature maintenance to a low-carbon, high-efficiency approach is imperative. Summary of the Invention

[0004] The purpose of the present invention is to overcome the shortcomings of the above-mentioned prior art and provide an oil tank temperature maintenance system with a built-in phase change heat storage body, which not only meets the low-carbon and energy-saving requirements of crude oil temperature maintenance, but also effectively reduces the heat exchange between crude oil and the outside world.

[0005] In order to solve the problems existing in the background technology, the present invention adopts the following technical solution: it includes an oil storage tank, a solar thermal collection unit, a photovoltaic power generation unit, a waste heat utilization unit, an intelligent temperature control unit and a power storage unit, the solar thermal collection unit is connected to the top of the oil storage tank through a heating pipeline, and the side wall of the oil storage tank is connected to the solar thermal collection unit through a return pipeline; the photovoltaic power generation unit is connected to the electric energy transfer control device, and the electric energy transfer control device is connected to the power storage unit and the waste heat utilization unit respectively, wherein the power storage unit is connected to the oil storage tank through a power supply line, an industrial waste heat exchange pipe is installed in the waste heat utilization unit, the waste heat utilization unit is connected to the oil storage tank through a heating pipeline, and the oil storage tank is connected to the waste heat utilization unit through a return pipeline; the electric energy transfer control device is connected to the power grid.

[0006] A circulation pump is installed on the heating pipeline and the return pipeline between the oil storage tank and the solar thermal collection unit, and the circulation pump is electrically connected to the intelligent temperature control unit.

[0007] A pipe is provided on the return pipe between the oil storage tank and the solar thermal collection unit, the pipe is connected to the oil storage tank, an electric valve is installed on the pipe, and the electric valve is electrically connected to the intelligent temperature control unit.

[0008] A circulation pump and an electric valve are installed on the heating pipeline between the waste heat utilization unit and the oil storage tank, and the circulation pump and the electric valve are electrically connected to the intelligent temperature control unit respectively.

[0009] The oil storage tank is divided into three chambers from the inside to the outside, namely the crude oil area, the heating area and the energy storage area. The crude oil area is equipped with a heating coil, which is in a double helix shape. The inside of the heating area and the energy storage area are both phase change energy storage units, and the phase change energy storage units are honeycomb heat storage units.

[0010] The phase change material used in the phase change energy storage unit inside the heating zone is nano metal particles; the phase change material used in the phase change energy storage unit inside the energy storage zone is paraffin.

[0011] The outer wall of the crude oil zone is wrapped with a heating tape.

[0012] One end of the heating coil is connected to the waste heat utilization unit through a heating pipeline, and an inlet valve is provided on the heating pipeline. The other end of the heating coil is connected to the waste heat utilization unit through a return pipeline, and an outlet valve is provided on the return pipeline. The outlet valve and the inlet valve are electrically connected to the intelligent temperature control unit respectively.

[0013] The oil storage tank is provided with a plurality of temperature sensing elements, and the temperature sensing elements are connected to the intelligent temperature control unit through wires.

[0014] An electric heating plate is installed at the bottom of the oil storage tank, the electric heating plate is connected to the power storage unit, and the outer wall of the oil storage tank is wrapped with glass wool.

[0015] The beneficial effects of the present invention are: 1. The entire system can effectively utilize solar energy and industrial waste heat for heating. In the absence of sunlight, it can also use municipal grid electricity or green electricity during off-peak hours for electric heating, effectively solving the problems of intermittent and unstable heating from new energy sources and low utilization rate of industrial waste heat.

[0016] 2. The phase change energy storage in the oil storage tank adopts a cascade layered design, filled with paraffin wax with different melting points, and the phase change energy storage unit is filled with nano metal particles to improve the thermal efficiency of the phase change energy storage.

[0017] 3. According to the specific operating scenario, the intelligent temperature control unit controls the opening and closing of the electric heating plate and heating tape in the system to stabilize the temperature of the oil storage tank in real time.

[0018] This invention, inspired by phase-change heat storage and exchange wall technology in the field of building energy conservation, combines existing phase-change oil storage tanks with oil storage tanks, reducing heat exchange between crude oil and the outside world. This passive heating method significantly increases the duration of crude oil temperature maintenance. This system effectively reduces conventional energy consumption and has promising market prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1It is a system diagram of the present invention; Figure 2 It is a structural schematic diagram of the oil storage tank of the present invention; Figure 3 is a cross-sectional view of the oil storage tank of the present invention; Figure 4 Schematic diagram of the distribution of the heating belt of the present invention. DETAILED DESCRIPTION

[0020] With reference to the figures, the present invention specifically adopts the following implementation mode: it includes an oil storage tank 1, a solar thermal collection unit 2), a photovoltaic power generation unit 3, a waste heat utilization unit 4, an intelligent temperature control unit 7 and a power storage unit 8, wherein the solar thermal collection unit 2 is connected to the top of the oil storage tank 1 through a heating pipeline 22, and the side wall of the oil storage tank 1 is connected to the solar thermal collection unit 2 through a return pipeline 23; the photovoltaic power generation unit 3 is connected to an electric energy transfer control device 24, and the electric energy transfer control device 24 is respectively connected to the power storage unit 8 and the waste heat utilization unit 4, wherein the power storage unit 8 is connected to the oil storage tank 1 through a power supply line 21, an industrial waste heat exchange pipe 20 is installed in the waste heat utilization unit 4, the waste heat utilization unit 4 is connected to the oil storage tank 1 through a heating pipeline 22, and the oil storage tank 1 is connected to the waste heat utilization unit 4 through a return pipeline 23; the electric energy transfer control device 24 is connected to the power grid 25.

[0021] A circulating pump 5 is installed on both the heating pipeline 22 and the return pipeline 23 between the oil storage tank 1 and the solar thermal unit 2. The circulating pump 5 is electrically connected to the intelligent temperature control unit 7. A pipe 26 is installed on the return pipeline 22 between the oil storage tank 1 and the solar thermal unit 2. The pipe 26 is connected to the oil storage tank 1 and an electric valve 6 is installed on the pipe 26. The electric valve 6 is electrically connected to the intelligent temperature control unit 7. A circulating pump 5 and an electric valve 6 are installed on the heating pipeline 22 between the waste heat utilization unit 4 and the oil storage tank 1. The circulating pump 5 and the electric valve 6 are electrically connected to the intelligent temperature control unit 7. The oil storage tank 1 is divided into three chambers from the inside to the outside: a crude oil zone 17, a heating zone 18, and an energy storage zone 19. A heating coil 9 is installed in the crude oil zone 17. The heating coil 9 is in a double-helix shape. Both the heating zone 18 and the energy storage zone 19 contain a phase change energy storage unit 12. The phase change energy storage unit 12 is a honeycomb heat storage unit. The phase change material used in the phase change energy storage unit 12 within the heating zone 18 is nano-metal particles 26; the phase change material used in the phase change energy storage unit 12 within the energy storage zone 19 is paraffin 27. The outer wall of the crude oil zone 17 is wrapped with a heating cable 14. One end of the heating coil 9 is connected to the waste heat utilization unit 4 through a heating pipeline 22, and this heating pipeline 22 is provided with an inlet valve 15. The other end of the heating coil 9 is connected to the waste heat utilization unit 4 through a return pipeline 23, and this return pipeline 23 is provided with an outlet valve 16. The outlet valve 16 and the inlet valve 15 are respectively electrically connected to the intelligent temperature control unit 7. Several temperature sensing elements 10 are provided in the oil storage tank 1, and the temperature sensing elements 10 are all connected to the intelligent temperature control unit 7 through wires. An electric heating plate 11 is installed at the bottom of the oil storage tank 1, and the electric heating plate 11 is connected to the power storage unit 8. The outer wall of the oil storage tank 1 is wrapped with glass wool 13.

[0022] The electric heating plate 11 is connected to the power storage unit 8 and is located at the bottom of the oil storage tank 1. When the photovoltaic power generation unit 3 is short of energy or encounters extreme conditions, the system draws power from the power grid 25 and operates the electric heating plate 11 and the heating tape 14 at the same time to ensure the stability of the overall system operation; the measuring points of the temperature sensing element 10 are arranged in a snowflake shape at the fluid inlet and outlet of the heating coil 9 and in the oil storage tank 1 with the heating plate tube as the reference, and it is connected to the intelligent unit 7; the electric valve 6 and the electric heating plate 11 are controlled to start and stop by the intelligent temperature control unit according to the temperature sensing element 10.

[0023] The phase-change balls arranged within the phase-change energy storage unit 12 utilize a cascaded, layered design, dividing it into an outer, high-melting-point energy storage zone 19 and an inner, low-melting-point heating zone 18, separated by a heat exchange wall. The portions of the oil tank 1 and heating coil 9 that come into contact with the outside world are wrapped in glass wool 13, a thermally insulating material. The heat exchange walls between the various zones within the oil tank 1 are constructed from alumina.

[0024] The oil storage tank 1 is divided into three areas, the middle one is the crude oil area 17, the second one is the heating area 18, and the outermost layer is the energy storage area 19; the crude oil area 17 is arranged with heating plate tubes 9 distributed in a double helix shape, and the phase change heat of the heating area 18 and the energy storage area 19 is combined to carry out systematic heating and temperature maintenance, effectively avoiding the problem of temperature dead zone when heating the crude oil area 17.

[0025] The heating fluid and phase-change energy storage unit 12 both draw their energy from renewable energy sources. The heating fluid is heated by solar energy when sunlight is sufficient, and by industrial waste heat when sunlight is insufficient. The energy storage area of ​​the phase-change energy storage unit 12 is directly powered by waste heat utilization unit 4, while the heating area 18 is directly powered by solar energy. To ensure the stability of the energy supply system, heating cables 14 are unevenly distributed around the outer wall of the crude oil area 17 of the oil storage tank 1. These heating cables 14 surround the outer wall of the crude oil area 17 and are unevenly distributed, increasing in number from bottom to top. An electric heating plate 11 is located at the bottom of the oil storage tank 1, supplied with photovoltaic and mains electricity.

[0026] Temperature sensors 10 are installed at the fluid inlet and outlet of the heating coil 9. Inside the tank, these sensors, evenly distributed throughout the tank and located at four blind spots, are attached to the heating coil 9. Intelligent temperature control units 7 monitor the temperature of these points in real time. These sensors 10 transmit this data to the intelligent temperature control unit 7. If the crude oil temperature falls below the set temperature, the intelligent temperature control unit 7 initiates a command to activate the heating cable 14, heating the crude oil.

[0027] Phase-change energy storage unit 12 utilizes a honeycomb layout, storing phase-change materials containing nano-metal particles and paraffin wax within hexagonal stainless steel honeycomb thermal storage cells. The cells are filled with paraffin wax, along with nano-metal particles to enhance thermal conductivity. The cells utilize a cascaded, layered design, with heating zone 18 housing a paraffin-based phase-change energy storage unit with a melting point of 45°C, and storage zone 19 housing a paraffin-based phase-change energy storage unit with a melting point of 65°C. This utilizes the latent heat of the phase-change materials with different melting points to achieve thermal utilization.

[0028] Use industrial waste heat, solar heat, photovoltaic and other clean energy sources to replace traditional gas boiler heat supply, reducing conventional energy consumption The oil storage tank 1, heating coil 9, electric valve 6, inlet valve 15, and outlet valve 16 are all made of corrosion-resistant 316 stainless steel. The inner and outer surfaces of the heating coil 9 are coated with urushiol epoxy anti-corrosion material to prevent the phase change material and heat transfer fluid from corroding the fluid channel.

[0029] The specific working process of the invention is as follows: Energy supply process: Combined with meteorological and environmental conditions, the following energy supply methods are proposed: (1) Solar thermal energy supply: When the sunlight intensity is sufficient (light intensity > 300W / m2), the heat transfer fluid absorbs heat from the solar thermal collection unit 2 and transports it to the heating coil 9 after the temperature reaches the required level; the surplus solar energy is collected and converted into thermal energy and stored in the heating area 18 of the phase change energy storage unit 12 for passive heating of the crude oil area 17.

[0030] (2) Waste heat energy supply: When the sunlight intensity is insufficient (light intensity < 300W / m2) or in a night environment, the present invention cleverly utilizes industrial waste heat to obtain cheap energy. The waste heat of the flue gas from the heating furnace and the waste heat of the oily wastewater are mainly recovered through the waste heat utilization unit 4. The recovered flue gas waste heat enters the system through the heat charging port located at the top of the energy storage area 19 of the oil storage tank 1. The heat charging port is a DN100 movable piston head with a threaded locking connection method, which ensures the high efficiency and sealing of the waste heat transmission. The large amount of heat energy carried by the industrial waste heat is transferred to the phase change energy storage unit 12. The paraffin absorbs the heat to maintain the thermal energy reserve of the phase change ball in the energy storage area 19, meeting the continuous demand for crude oil temperature maintenance. The other part is directly exchanged with the heat transfer fluid, and then the heating coil 9 is used to maintain the temperature of the crude oil.

[0031] (3) Photovoltaic supplement: When the intensity of sunlight is sufficient, the photovoltaic power generation unit 3 stores the generated electricity in the power storage unit 8, and waits until the time is right to supply power to the heating cable 14. This method complements solar heating, makes full use of natural resources, and improves the diversity and stability of energy.

[0032] (4) Mains power supply: In addition to the above heating methods, the system can also use mains power for heating. During the off-peak period of the power grid 25, the municipal power grid 25 becomes the main source of energy. The power is transmitted to the electric heating plate 11 and the heating cable 14 through the charging port set at the bottom of the oil storage tank 1. The charging port supports 220V voltage and has the characteristics of quick plug-in connection, which ensures the convenience and stability of power supply. After receiving the power, the electric heating plate 11 starts to heat the entire oil storage tank 1; the heating cable 14 starts after the electric heating plate 11 has been working for a period of time, which is determined by the temperature measured by the temperature sensing element 10. The phase change energy storage unit 12 is filled with nano-metal particles. This structural design can effectively increase the thermal conductivity of paraffin. Under the action of the electric heating plate 11, heat is quickly transferred between the crude oil and the phase change energy storage unit 12. As the crude oil gradually heats up, the paraffin begins to store heat energy, preparing for the subsequent crude oil temperature maintenance process.

[0033] During the heat exchange process, temperature sensing element 10 monitors the temperature of various measurement points in real time, including the fluid inlet and outlet of heating coil 9 and various points in the crude oil zone. Temperature sensing elements 10 are arranged in a snowflake pattern to ensure accurate acquisition of temperature changes within the system and transmit the monitored data to intelligent temperature control unit 7. Intelligent temperature control unit 7, serving as the intelligent control core of the entire system, receives data from temperature sensing element 10 and rapidly analyzes and determines its accuracy. When the incoming liquid temperature meets the set temperature requirement, intelligent temperature control unit 7 issues a command, opening the inlet valve, allowing the heat transfer fluid to pass through heating coil 9 and exchange heat with crude oil zone 17. When the incoming liquid temperature is slightly below the set value, heating cable 14 is activated under the control of intelligent temperature control unit 7, and power storage unit 8 continuously supplies power to heating cable 14. When the crude oil temperature approaches or reaches the set value, heating to the crude oil ceases, and any excess heat is stored in phase change energy storage unit 12, which then maintains the crude oil temperature and effectively reduces heat exchange between the crude oil and the outside world.

[0034] This oil tank temperature maintenance system, which includes a built-in phase-change thermal storage element, effectively utilizes solar energy and industrial waste heat for heating. Even in the absence of sunlight, it can utilize off-peak municipal grid electricity or renewable energy for electric heating, effectively addressing the intermittent and unstable heating from renewable energy sources and the low utilization rate of industrial waste heat. The phase-change energy storage within the oil tank utilizes a cascaded, layered design, filled with paraffin waxes of varying melting points. Nano-metal particles are also incorporated into the phase-change energy storage unit to enhance its thermal efficiency. Based on the specific operating scenario, the intelligent temperature control unit controls the opening and closing of the electric heating plates and heating cables within the system, stabilizing the oil tank's temperature in real time.

[0035] In summary, a temperature maintenance system for oil storage tanks containing a built-in phase change heat storage body can effectively utilize solar heat, industrial waste heat, and photovoltaics for heating through energy supply devices; at the same time, in the absence of sunlight or even in extreme conditions, municipal grid electricity or green electricity during off-peak hours can be used to ensure electric heating, effectively solving the problems of intermittent and unstable heating from new energy sources such as solar energy and low utilization rate of industrial waste heat. This system combines oil storage tanks and phase change energy storage units with reference to the phase change energy storage walls in the field of building energy conservation; the phase change energy storage unit adopts a cascade layered design to improve heat transfer performance, greatly reducing the heat exchange between crude oil and the outside world. According to the specific operating scenario, the intelligent control center controls the start and stop of the electric heating plate and heating tape in the system to achieve real-time intelligent control of temperature, with the advantages of simple operation, stable operation, green and low carbon.

[0036] This invention, inspired by phase-change heat storage and exchange wall technology in the field of building energy conservation, combines existing phase-change oil storage tanks with oil storage tanks, reducing heat exchange between crude oil and the outside world. This passive heating method significantly increases the duration of crude oil temperature maintenance. This system effectively reduces conventional energy consumption and has promising market prospects.

Claims

1. An oil tank temperature maintenance system with a built-in phase change heat storage body, characterized by: The invention comprises an oil storage tank (1), a solar heat collection unit (2), a photovoltaic power generation unit (3), a waste heat utilization unit (4), an intelligent temperature control unit (7) and an electricity storage unit (8), wherein the solar heat collection unit (2) is connected to the top of the oil storage tank (1) via a heating pipeline (22), and the side wall of the oil storage tank (1) is connected to the solar heat collection unit (2) via a return pipeline (23); the photovoltaic power generation unit (3) is connected to an electric energy transfer control device (24), and the electric energy transfer control device ( 24) are respectively connected to the power storage unit (8) and the waste heat utilization unit (4), wherein the power storage unit (8) is connected to the oil storage tank (1) through the power supply line (21), the waste heat utilization unit (4) is installed with an industrial waste heat heat exchange pipe (20), the waste heat utilization unit (4) is connected to the oil storage tank (1) through the heating pipeline (22), and the oil storage tank (1) is connected to the waste heat utilization unit (4) through the return pipeline (23); the electric energy transfer control device (24) is connected to the power grid (25).

2. The oil tank temperature maintenance system with a built-in phase change heat storage body according to claim 1, characterized in that: A circulation pump (5) is installed on the heating pipeline (22) and the return pipeline (23) between the oil storage tank (1) and the solar thermal collection unit (2), and the circulation pump (5) is electrically connected to the intelligent temperature control unit (7).

3. The oil tank temperature maintenance system with a built-in phase change heat storage body according to claim 1, characterized in that: A pipe (26) is provided on the return pipe (22) between the oil storage tank (1) and the solar thermal collection unit (2), the pipe (26) is connected to the oil storage tank (1), an electric valve (6) is installed on the pipe (26), and the electric valve (6) is electrically connected to the intelligent temperature control unit (7).

4. The oil tank temperature maintenance system with a built-in phase change heat storage body according to claim 1, characterized in that: A circulation pump (5) and an electric valve (6) are installed on the heating pipeline (22) between the waste heat utilization unit (4) and the oil storage tank (1), and the circulation pump (5) and the electric valve (6) are electrically connected to the intelligent temperature control unit (7) respectively.

5. The oil tank temperature maintenance system with a built-in phase change heat storage body according to claim 1, characterized in that: The oil storage tank (1) is divided into three chambers from the inside to the outside, and the three chambers are a crude oil area (17), a heating area (18) and an energy storage area (19). A heating coil (9) is provided in the crude oil area (17), and the heating coil (9) is in a double helical shape. The interior of the heating area (18) and the interior of the energy storage area (19) are both phase change energy storage units (12), and the phase change energy storage units (12) are honeycomb heat storage units.

6. The oil tank temperature maintenance system with a built-in phase change heat storage body according to claim 5, characterized in that: The phase change material used in the phase change energy storage unit (12) inside the heating zone (18) is nano-metal particles (26); the phase change material used in the phase change energy storage unit (12) inside the energy storage zone (19) is paraffin (27).

7. The oil tank temperature maintenance system with a built-in phase change heat storage body according to claim 5, characterized in that: The outer wall of the crude oil zone (17) is wrapped with a heating tape (14).

8. The oil tank temperature maintenance system with a built-in phase change heat storage body according to claim 1 or 5, characterized in that: One end of the heating coil (9) is connected to the waste heat utilization unit (4) through a heating pipeline (22), and the heating pipeline (22) is provided with an inlet valve (15). The other end of the heating coil (9) is connected to the waste heat utilization unit (4) through a return pipeline (23), and the return pipeline (23) is provided with an outlet valve (16). The outlet valve (16) and the inlet valve (15) are respectively electrically connected to the intelligent temperature control unit (7).

9. The oil tank temperature maintenance system with a built-in phase change heat storage body according to claim 1, characterized in that: The oil storage tank (1) is provided with a plurality of temperature sensing elements (10), and the temperature sensing elements (10) are all connected to the intelligent temperature control unit (7) via wires.

10. The oil tank temperature maintenance system with a built-in phase change heat storage body according to claim 1, characterized in that: An electric heating plate (11) is installed at the bottom of the oil storage tank (1), the electric heating plate (11) is connected to the power storage unit (8), and the outer wall of the oil storage tank (1) is wrapped with glass wool (13).

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