A phase change enhanced heat conduction device and its application method for oil spill combustion at sea surface

Abstract

This invention relates to the technical field of marine oil spill treatment equipment, specifically disclosing a phase change enhanced heat conduction device for marine oil spill combustion. The device includes a metal heat-conducting rod, which is a vacuum high-temperature heat pipe. The inner wall of the high-temperature heat pipe is lined with a metal fiber felt having a porous structure. A potassium-sodium liquid alloy is placed inside the high-temperature heat pipe. The device also includes a floating assembly fixedly connected to the metal heat-conducting rod, which provides buoyancy. Before deployment, the required counterweight is calculated based on the seawater density. This counterweight calculation ensures that the bottom of the high-temperature heat pipe remains within the oil spill layer after deployment and does not immerse itself in the seawater. This solution addresses the problem of existing methods using metal heat-conducting rods to increase the combustion rate, where the metal heat-conducting rods are difficult to float on the sea surface.

Description

Technical Field

[0001] This invention relates to the technical field of marine oil spill treatment equipment, specifically to a phase change enhanced heat conduction device and its usage method for marine oil spill combustion. Background Technology

[0002] Due to the complexity of offshore oil and gas development processes and equipment operation, there is a risk of major hazardous accidents such as oil and gas leaks, fires, explosions, and blowouts. Once these accidents occur, in addition to causing casualties and damage to offshore platform structures, they often result in large-scale crude oil spills, i.e., oil spills on the sea surface. Furthermore, besides the leakage risks during offshore oil and gas extraction, the risks during transportation should also be considered. With the annual increase in global oil and gas resource consumption and the uneven distribution of global resources, the volume of offshore oil and gas transportation is increasing year by year, and the risk of oil spills caused by tanker accidents is also rising. While the economic losses from oil spills on the sea surface are limited, the environmental impact is enormous, and crude oil contains many toxic substances that are difficult to decompose, the effects of which typically last for several years.

[0003] To reduce the pollution of marine oil spills, commonly used methods for oil spill cleanup include mechanical, chemical, biological, and in-situ combustion methods. In-situ combustion is considered a superior method due to its rapid implementation and lower cost, particularly suitable for large-scale spills or those located far from the coast. This method involves first using oil booms to contain the spill, followed by direct combustion. In-situ combustion burns the oil at the source, significantly reducing its impact on the water and preventing it from spreading to the shore, thus minimizing contact with birds and mammals. If in-situ combustion is implemented promptly, the cleanup rate can reach over 90%. However, in this method, the energy transferred from the flame to the fuel surface is less than 5% of the heat radiation energy of the flame. Most of the heat generated by combustion is dissipated into the environment and cannot be effectively absorbed by the oil layer. This results in a low volatile rate of flammable oil and gas due to insufficient heat received by the oil layer, which affects the rate of on-site combustion of oil spills on the sea surface and the efficiency of cleanup. At the same time, due to poor heat conduction during combustion, some combustion is incomplete and there are many harmful residues.

[0004] To improve the utilization rate of flame energy, the prior art, patent publication number CN106400756A, proposes a method to improve the efficiency of in-situ combustion in treating marine oil spills by placing vertical metal heat-conducting rods inside the oil boom. The high-temperature heat energy of the flame is transferred to the oil spill along the vertical columnar metal heat-conducting rods, thereby increasing the heat transferred from the flame to the oil spill layer during combustion and thus improving the combustion rate and efficiency of in-situ combustion in treating marine oil spills.

[0005] However, the aforementioned solution is difficult to achieve due to the slender and heavy metal heat-conducting rod itself, making it challenging to float vertically on water constantly battered by waves. Patent publication CN109914364A discloses a device for improving the efficiency of in-situ combustion in treating marine oil spills, which involves installing multiple cross-shaped metal plates on a circular pontoon to enhance combustion efficiency. However, this solution is structurally complex and heavy, and the solid metal plates have limited thermal conductivity. Therefore, this device has shortcomings in terms of deployment, recovery, transportation, and the speed of cleanup in response to large-scale oil spills. Summary of the Invention

[0006] The present invention aims to provide a phase change enhanced heat conduction device for the burning of oil spills on the sea surface, which solves the problems of low efficiency and inconvenient operation of existing heat conduction devices with better heat conduction performance, higher oil spill cleanup rate and simpler operation process.

[0007] To achieve the above objectives, the present invention adopts the following technical solution:

[0008] A phase change enhanced heat conduction device for oil spill combustion at sea includes a metal heat conduction rod, which is a vacuum high-temperature heat pipe. The inner wall of the high-temperature heat pipe is lined with a metal fiber felt with several pore structures. A potassium-sodium liquid alloy is placed inside the high-temperature heat pipe. The device also includes a floating assembly fixedly connected to the metal heat conduction rod. The floating assembly is used to provide buoyancy. The top of the floating assembly is connected to the high-temperature heat pipe, and the bottom of the floating assembly is equipped with a counterweight.

[0009] The principle and advantages of this scheme are as follows: In practical application, the metal heat-conducting rod is set as a high-temperature heat pipe with an internal vacuum and metal fiber felt. After the high-temperature heat pipe is deployed, the top of the high-temperature heat pipe exposed in the oil layer is the evaporation end of the potassium-sodium liquid alloy phase change heat transfer medium (that is, the position where the combustion flame is generated), while the end of the high-temperature heat pipe in the oil layer is the condensation end. When the temperature of the evaporation end of the high-temperature heat pipe rises, the potassium-sodium liquid alloy climbs along the inner wall with metal fiber felt and absorbs the heat introduced into the high-temperature heat pipe by the flame and gradually vaporizes. The metal vapor formed by vaporization moves down from the top of the central channel surrounded by metal fiber felt to the low-temperature condensation end immersed in the oil layer and releases heat to liquefy. That is, the high-temperature heat pipe repeatedly changes and circulates between the vapor and liquid phases in its tube, so that heat is quickly and efficiently transferred from the evaporation end to the condensation end, realizing the effective entry of combustion heat into the oil layer, thereby improving the oil spill combustion and removal rate.

[0010] In practical applications, boiling is clearly observed on the lower outer wall of the high-temperature heat pipe immersed in the oil layer. This heat transfer phenomenon has a higher heat transfer coefficient than convection heat transfer, which can further accelerate the introduction of heat into the oil layer and increase the oil layer temperature. At the same time, the oil and gas bubbles generated during the boiling process release the combustible oil and gas directly into the flame after they burst at the liquid surface, thereby increasing the combustion rate of the oil layer and reducing combustion residue. In other words, compared with the heat conduction method of conventional metal heat-conducting rods, the high-temperature heat pipe in this solution greatly improves the heat conduction efficiency, which is beneficial to improving the combustion rate and efficiency. Furthermore, because the bottom of the floating assembly is equipped with a counterweight and the top of the floating assembly is equipped with a vacuum high-temperature heat pipe, the entire device has a simple structure and the center of gravity is located on the bottom counterweight. This makes it convenient to launch or deploy the entire heat-conducting device directly into the oil boom from a distance. After deployment, because the center of gravity of the device is located at the bottom and the top section is a vacuum heat pipe with low density and weight, the heat-conducting device can automatically adjust its attitude after launch. This ensures that the high-temperature heat pipe remains vertically floating regardless of the waves or changes in the launch angle, ensuring that the efficient heat conduction of the high-temperature heat pipe is not affected at all.

[0011] In addition, because the high-temperature heat pipe is a vacuum tube, it has a certain buoyancy on the sea surface, which reduces the buoyancy requirements of the floating components, thereby reducing the weight and structural complexity of the entire heat conduction device, reducing the difficulty of launch, reducing the requirements for transportation, and also reducing the difficulty of recovery. In other words, this solution reduces the difficulty of the heat conduction device in terms of deployment, recovery and transportation.

[0012] Preferably, as an improvement, the floating assembly includes a float filled with high-temperature resistant glass fiber foam.

[0013] The high-temperature resistant glass fiber foam in this solution can provide buoyancy for the floating components. Even if water enters the float due to poor sealing, it will not affect the floating of the high-temperature resistant glass fiber foam, ensuring that the buoyancy of the floating components is not affected by high temperature and water ingress.

[0014] Preferably, as an improvement, the float is made of metal, and a metal connecting seat is fixed between the float and the high-temperature heat pipe.

[0015] Preferably, as an improvement, the connecting seat includes an upper body and a lower body. The upper body includes a connecting plate integrally connected to the upper body and multiple reinforcing plates arranged circumferentially along the high-temperature heat pipe. The connecting plate is fixedly connected to the bottom of the high-temperature heat pipe, and the reinforcing plates are fixedly connected to the outer wall of the high-temperature heat pipe. The lower body is fixed to the floating assembly, and the connecting plate can be fixedly connected to the lower body. This solution makes the connection between the high-temperature heat pipe and the floating assembly simple and secure, and facilitates the replacement of damaged parts.

[0016] Preferably, as an improvement, the counterweight includes a placement tube and a counterweight body. The placement tube is fixedly connected to the bottom of the floating assembly, and the number of counterweight bodies is at least one, which can be stacked inside the placement tube. This design, through the placement tube, further lowers the center of gravity of the entire heat-conducting device, ensuring that the entire device can automatically adjust its attitude to maintain a vertical state in seawater. Furthermore, by conducting weight adjustment tests on the counterweight before deployment, it can be ensured that the bottom of the high-temperature heat pipe will float in the oil layer after deployment.

[0017] The present invention also provides a method for using a phase change enhanced heat conduction device for oil spill combustion at sea surface. Specifically, before deploying the heat conduction device, the required counterweight is calculated based on the density of seawater. The counterweight calculation ensures that the bottom of the high-temperature heat pipe is in the oil spill layer and does not penetrate into the seawater after being deployed to the sea surface. In other words, it ensures that the high-temperature heat pipe is placed in the position of the flame and the oil layer, minimizing or eliminating contact with seawater, and avoiding rapid heat loss caused by contact between the high-temperature heat pipe and seawater.

[0018] Preferably, as an improvement, when the oil boom is used to contain the oil spill, it is open, with both ends held in place by tugboats, and the heat-conducting device located within the combustion zone of the oil boom. By holding the oil boom in place by tugboats, the oil boom can be kept relatively stable in the oil spill area, ensuring that the oil spill remains within the boom and does not disperse. At the same time, when the oil spill moves due to the impact of sea winds or waves, the floating heat-conducting device can be moved by the tugboats pulling the oil boom, ensuring that the heat-conducting device remains within the combustion zone of the oil spill. Attached Figure Description

[0019] Figure 1 This is a front view of an embodiment of the present invention.

[0020] Figure 2 This is a front sectional view of an embodiment of the present invention.

[0021] Figure 3 This is a schematic diagram showing the connection relationship between the high-temperature heat pipe and the floating assembly in an embodiment of the present invention.

[0022] Figure 4 This is a schematic diagram illustrating the vapor-liquid phase change principle within a high-temperature heat pipe in an embodiment of the present invention.

[0023] Figure 5 This is a schematic diagram illustrating the generation of bubbles when a high-temperature heat pipe is inserted into a burning oil layer in an embodiment of the present invention.

[0024] Figure 6 This is a schematic diagram illustrating the use of a heat-conducting device in an embodiment of the invention. Detailed Implementation

[0025] The following detailed description illustrates the specific implementation method:

[0026] The reference numerals in the accompanying drawings include: high-temperature heat pipe 10, floating assembly 20, metal fiber felt 11, float 21, suspended particles 211, counterweight 22, placement tube 221, counterweight body 222, connecting seat 30, upper seat 31, connecting plate 311, reinforcing plate 312, lower seat 32, upper connecting plate 321, connecting cylinder 322, and lower connecting plate 323.

[0027] The basic implementation examples are as follows: Figures 1 to 6 As shown, a phase change enhanced heat conduction device for oil spill combustion at sea includes a high-temperature heat pipe 10 and a floating assembly 20. The high-temperature heat pipe 10 is a vacuum tube. A metal fiber felt 11 with several pore structures is fixedly placed on the vertical inner wall of the high-temperature heat pipe 10. The metal fiber felt 11 forms a ring and is attached to the inner wall of the high-temperature heat pipe 10. A potassium-sodium liquid alloy (i.e., NaK-78, with a mass ratio of 78% metallic sodium and 22% metallic potassium) is stored in the high-temperature heat pipe 10. The metal fiber felt 11 has many capillaries, which can provide sufficient adsorption force to the potassium-sodium liquid alloy so that the liquid metal can climb along the inner wall of the high-temperature heat pipe 10 until it vaporizes under high temperature heating.

[0028] The floating assembly 20 provides buoyancy to the entire heat-conducting device, enabling it to float on the sea surface. Specifically, the floating assembly 20 includes a float 21 and a counterweight 22. The float 21 is filled with porous suspended particles 211, which are fire-resistant fiberglass foam. The counterweight 22 is fixed to the bottom of the float 21.

[0029] The float 21 is made of metal, and a metal connecting seat 30 is fixed between the float 21 and the high-temperature heat pipe 10. The connecting seat 30 includes an upper seat body 31 and a lower seat body 32. The upper seat body 31 includes a connecting plate 311 connected as one piece and a plurality of reinforcing plates 312 evenly distributed along the circumference of the high-temperature heat pipe 10. The connecting plate 311 is welded to the bottom of the high-temperature heat pipe 10, and the reinforcing plates 312 are welded to the outer wall of the high-temperature heat pipe 10. The lower seat body 32 includes an upper connecting plate 321, a connecting cylinder 322, and a lower connecting plate 323 connected as one piece and in sequence. The upper connecting plate 321 can be riveted to the connecting plate 311, and the lower connecting plate 323 can be welded to the top of the float 21. The inner diameter of the connecting cylinder 322 is larger than the outer diameter of the high-temperature heat pipe 10.

[0030] The counterweight 22 includes a placement tube 221 and a counterweight body 222. The placement tube 221 is threaded to the bottom of the float 21. The number of counterweight bodies 222 is at least one. The counterweight bodies 222 can be stacked inside the placement tube 221. The number of counterweight bodies 222 can be adjusted according to requirements.

[0031] When using the aforementioned heat-conducting device to handle oil spills via combustion, the oil boom is open, with both ends held in place by tugboats. Before being deployed onto the oil boom, the required counterweight 22 is calculated based on the seawater density to ensure that the bottom of the high-temperature heat pipe 10 remains within the oil spill layer and does not immerse itself in the seawater after the device is placed in the seawater. The heat-conducting device is located within the combustion zone of the oil boom to maximize its effectiveness.

[0032] When using this embodiment, the entire heat-conducting device can be launched directly from a distance or deployed into the oil boom, such as from a tugboat. Because the heat-conducting device has its own floating component 20, the heat-conducting device deployed into the oil boom will automatically maintain a floating state under the action of the floating component 20, thereby solving the problem that metal heat-conducting rods cannot float on the sea surface in the prior art.

[0033] Furthermore, in this embodiment, after the high-temperature heat pipe 10 is deployed, the top of the high-temperature heat pipe 10 exposed above the oil layer is the evaporation end of the potassium-sodium liquid alloy phase change heat transfer medium (i.e., the location where the combustion flame is generated), while the end of the high-temperature heat pipe 10 in the oil layer is the condensation end. When the temperature of the evaporation end of the high-temperature heat pipe 10 rises, the potassium-sodium liquid alloy climbs along the inner wall of the metal fiber felt 11 and absorbs the heat introduced into the high-temperature heat pipe by the flame, gradually vaporizing. The vaporized metal vapor moves downward from the top of the central channel enclosed by the metal fiber felt 11 to the low-temperature condensation end immersed in the oil layer and releases heat to liquefy. Because the high-temperature heat pipe 10 is in the continuously burning oil spill combustion zone, the high-temperature heat pipe 10 undergoes repeated vapor-liquid two-phase transformation and circulation, and heat is quickly and efficiently transferred from the evaporation end to the condensation end, realizing the effective entry of combustion heat into the oil layer, thereby improving the oil spill combustion and removal rate. In practical applications, it can be clearly observed that the high-temperature heat pipe 10 continuously bubbles when in contact with the oil layer (e.g., Figure 5 As shown in the diagram, research and analysis revealed that this phenomenon occurs because the temperature of the wall surface in contact with the oil layer at the high-temperature heat pipe 10 exceeds the boiling point of the oil layer. This causes a large amount of combustible fuel gas in the oil layer to be released into the flame as the bubbles burst, greatly improving combustion efficiency and reducing combustion residue. This also confirms that the wall surface in contact with the oil layer at the high-temperature heat pipe in this embodiment has excellent thermal conductivity. Furthermore, the bubbling process also transfers heat to a greater distance, increasing the area of ​​the oil layer heated by the high-temperature heat pipe 10 and further improving heating efficiency.

[0034] Furthermore, because the high-temperature heat pipe 10 is a vacuum tube, its density and weight are greatly reduced, making it easier for the high-temperature heat pipe 10 to float in seawater and for the heat transfer device to be deployed. In addition, the floating structure of the floating assembly 20 and the counterweight 22 ensure that even when the heat transfer device is deployed at a distance or is constantly subjected to wave action, the high-temperature heat pipe 10 remains vertically floating, guaranteeing its smooth and stable operation.

[0035] In addition, since the high-temperature heat pipe 10 is a vacuum tube, it has a certain buoyancy on the sea surface, which reduces the buoyancy requirement of the floating component 20, thereby reducing the weight of the entire heat conduction device, reducing the difficulty of launch, reducing the requirements for transportation, and also reducing the difficulty of recovery. In other words, this embodiment reduces the difficulty of the heat conduction device in terms of deployment, recovery and transportation.

[0036] The above descriptions are merely embodiments of the present invention, and common knowledge such as specific technical solutions and / or characteristics are not described in detail here. It should be noted that those skilled in the art can make various modifications and improvements without departing from the technical solutions of the present invention, and these should also be considered within the scope of protection of the present invention. These modifications and improvements will not affect the effectiveness of the implementation of the present invention or the practicality of the patent. The scope of protection claimed in this application should be determined by the content of its claims, and the specific embodiments described in the specification can be used to interpret the content of the claims.

Claims

1. A phase change enhanced heat conduction device for sea surface oil spill combustion method, comprising a metal heat conduction rod, characterized in that: The metal heat-conducting rod is a high-temperature heat pipe in vacuum, the inner wall of the high-temperature heat pipe is provided with a metal fiber felt with a plurality of porous structures, the high-temperature heat pipe is provided with a potassium-sodium liquid alloy, and the metal heat-conducting rod is fixedly connected with a floating assembly, the floating assembly is used for providing buoyancy, the floating assembly is connected with the high-temperature heat pipe at the top, and the floating assembly is provided with a counterweight at the bottom.

2. The phase change enhanced heat conduction device for sea surface oil spill combustion method according to claim 1, characterized in that: The floating assembly comprises a buoy, and the buoy is filled with high-temperature-resistant glass fiber foam.

3. The phase change enhanced heat conduction device for sea surface oil spill combustion method according to claim 2, characterized in that: The buoy is made of metal, and a connecting seat made of metal is fixed between the buoy and the high-temperature heat pipe.

4. The phase change enhanced heat conduction device for sea surface oil spill combustion method according to claim 3, characterized in that: The connecting seat comprises an upper seat body and a lower seat body, the upper seat body comprises a connecting plate and a plurality of reinforcing plates arranged along the circumference of the high-temperature heat pipe and connected into one body, the connecting plate is fixedly connected with the bottom of the high-temperature heat pipe, the reinforcing plates are fixedly connected with the outer wall of the high-temperature heat pipe, the lower seat body is fixed on the floating assembly, and the connecting plate can be fixedly connected with the lower seat body.

5. The phase change enhanced heat conduction device for sea surface oil spill combustion method according to any one of claims 1-4, characterized in that: The counterweight comprises a placing pipe and a counterweight body, the placing pipe is fixedly connected with the bottom of the floating assembly, the number of the counterweight body is at least one, and the counterweight body can be stacked in the placing pipe.

6. The method of using the phase change enhanced heat conduction device against sea surface oil spill combustion method according to any one of claims 1-4, characterized in that, Before the heat-conducting device is put into the sea, the required counterweight is calculated according to the seawater density, and the high-temperature heat pipe can be ensured to be located in the oil spill layer and not inserted into the seawater after being put into the sea by the counterweight calculation.

7. The method of claim 6, wherein the method is characterized in that: When the oil fence is used for surrounding oil, the oil fence is open, two ends of the oil fence are pulled by a tugboat, and the heat-conducting device is located in the combustion area in the oil fence.

Images