Apparatus for combusting Boil Off Gas

Abstract

The present invention relates to an evaporative gas combustion device. The evaporative gas combustion device is a combustion device for burning evaporative gas that has been vaporized and evaporated from liquefied natural gas, and is characterized by comprising: an evaporative gas supply unit having a main body portion formed with an inlet portion into which the evaporative gas is introduced and an outlet portion into which the introduced evaporative gas is discharged, and a cover portion covering the upper surface of the main body portion; an external air supply unit disposed around the periphery of the evaporative gas supply unit and spraying external air upward; and a plurality of ignition units disposed along the periphery of the evaporative gas supply unit.

Description

Technology Field

[0001] The present invention relates to an evaporative gas combustion device, and more particularly to an evaporative gas combustion device that facilitates the combustion of evaporative gas to prevent unburned evaporative gas from being discharged into the atmosphere. Background Technology

[0002] Generally, liquefied natural gas (LNG) is produced by liquefying natural gas to 1 / 600 of its original volume, storing it, and then transporting it via ships. LNG carriers are equipped with tanks to store LNG. When LNG is stored in liquid form in these tanks for transport, heat penetration occurs, causing the gas to vaporize and evaporate. This gas is called Boil-Off Gas (BOG). Additionally, to eliminate the risk of explosion during the loading and unloading of LNG, the tanks undergo an inerting process. As a result, a mixture of the vaporized Boil-Off Gas and inert Gas is generated; since this mixture cannot be released into the atmosphere, it is combusted using a combustion device.

[0003] The present invention aims to provide a system that enables sufficient combustion of evaporated gas and allows for smooth combustion even when the flow rate of inert gas is high. The problem to be solved

[0004] The present invention was devised to improve the problems described above, and aims to provide an evaporative gas combustion device that facilitates the combustion of evaporative gas to prevent unburned evaporative gas from being discharged into the atmosphere, and also improves the ignition efficiency for the combustion of evaporative gas even when a large amount of inert gas is contained. means of solving the problem

[0005] An evaporative gas combustion device according to an embodiment of the present invention is a combustion device for burning evaporative gas that has been vaporized and evaporated from liquefied natural gas, characterized by comprising: an evaporative gas supply unit having a main body portion formed with an inlet portion into which the evaporative gas is introduced and an outlet portion into which the introduced evaporative gas is discharged, and a cover portion covering the upper surface of the main body portion; an external air supply unit disposed around the periphery of the evaporative gas supply unit and spraying external air upward; and a plurality of ignition units disposed along the periphery of the evaporative gas supply unit.

[0006] In addition, the main body of the above-mentioned evaporative gas supply unit is formed in a cylindrical shape, and the discharge unit includes a plurality of discharge holes formed around the circumference of the main body unit, so that the evaporative gas introduced into the interior of the main body unit is discharged radially outward through the discharge holes, and the discharge holes are spaced apart from each other in the vertical direction and arranged side by side to form a single row, and it is preferable that a plurality of such rows are formed in the circumference direction of the main body unit.

[0007] In addition, it is preferable that the discharge port be formed horizontally or downwardly inclined on the inner surface of the evaporative gas supply unit so as to spray the evaporative gas in a horizontal direction or at a downward inclination.

[0008] Additionally, the ignition unit is formed in a number corresponding to the number of the rows, and the discharge hole located at the bottom of the row faces the ignition unit; it is preferable that the bottom discharge hole includes a plurality of sub-discharge holes having a diameter smaller than that of the discharge hole positioned above it.

[0009] Additionally, the above-mentioned external air supply unit comprises: a disc-shaped top plate portion having a mounting hole formed in the center for mounting the above-mentioned evaporative gas supply unit; and a side plate portion formed in a band shape with an upper portion connected to the circumference of the above-mentioned top plate portion and extending downward. The above-mentioned top plate portion includes a first injection hole disposed on the circumference of a virtual circle having a first diameter from the center of the above-mentioned top plate portion to eject external air, and a second injection hole disposed on the circumference of a virtual circle having a diameter larger than the first diameter to eject external air. The above-mentioned ignition unit is preferably provided on the upper surface of the above-mentioned top plate portion between the virtual circle of the first diameter and the outer circumference of the main body portion.

[0010] In addition, it is preferable that the virtual line penetrating the center of the discharge hole extends horizontally from the outer surface of the main body or is formed at an angle greater than 0° and less than or equal to 3° downward from the horizontal direction.

[0011] In addition, it is preferable to include a chamber portion in which evaporated gas discharged through the above-mentioned exhaust port and outside air ejected through the above-mentioned outside air supply unit are mixed and combusted, and to have a plurality of mounting brackets protruding from the perimeter of the side plate portion of the above-mentioned outside air supply unit, which are detachably coupled to a fastening portion formed on the lower side of the chamber portion.

[0012] In addition, it is preferable that the reinforcing member includes a reinforcing member arranged circumferentially spaced apart on the lower side of the upper plate to be coupled to the lower part of the upper plate and to support the upper plate. Effects of the invention

[0013] In an embodiment of the present invention, the evaporative gas combustion device performs the combustion of evaporative gas smoothly to prevent unburned evaporative gas from being discharged into the atmosphere, and provides the effect of improving the ignition efficiency for the combustion of evaporative gas even when a large amount of inert gas is contained.

[0014] In addition, it prevents methane slip caused by incomplete combustion, thereby providing the effect of significantly reducing CH4 emissions. Brief explanation of the drawing

[0015] FIG. 1 is a drawing illustrating an evaporative gas combustion device according to one embodiment of the present invention. Figure 2 is a cross-sectional view of the evaporative gas supply section. Specific details for implementing the invention

[0016] Hereinafter, various embodiments of the present invention are described in conjunction with the accompanying drawings. Since various embodiments of the present invention may be subject to various modifications and may have various forms, specific embodiments are illustrated in the drawings and described in detail. However, this is not intended to limit the various embodiments of the present invention to specific forms, and it should be understood that they include all modifications and / or equivalents and substitutions that fall within the spirit and scope of the various embodiments of the present invention. In relation to the description of the drawings, similar reference numerals have been used for similar components.

[0017] Expressions such as "comprising" or "may comprise" that may be used in various embodiments of the present invention indicate the existence of the disclosed function, operation, or component, etc., and do not limit one or more additional functions, operations, or components, etc. Furthermore, in various embodiments of the present invention, terms such as "comprising" or "having" are intended to specify the existence of the features, numbers, steps, operations, components, parts, or combinations thereof described in the specification, and should be understood as not precluding the existence or addition of one or more other features, numbers, steps, operations, components, parts, or combinations thereof.

[0018] When it is stated that a component is "connected" to another component, it should be understood that the component may be directly connected to the other component, or that a new component may exist between the component and the other component. On the other hand, when it is stated that a component is "directly connected" or "directly coupled" to another component, it should be understood that no new component exists between the component and the other component.

[0019] The terms used in the various embodiments of the present invention are used merely to describe specific embodiments and are not intended to limit the various embodiments of the present invention. The singular expression includes the plural expression unless the context clearly indicates otherwise.

[0020] Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as generally understood by those skilled in the art to which the various embodiments of the present invention pertain.

[0021] Terms such as those defined in commonly used dictionaries should be interpreted as having meanings consistent with their meanings in the context of the relevant technology, and should not be interpreted in an ideal or overly formal sense unless explicitly defined in the various embodiments of the present invention.

[0022] Hereinafter, preferred embodiments according to the present invention will be described in detail with reference to the attached drawings.

[0023] FIG. 1 is a drawing illustrating an evaporative gas combustion device according to one embodiment of the present invention, and FIG. 2 is a cross-sectional view of an evaporative gas supply unit.

[0024] The present invention relates to a combustion device for burning boil-off gas when liquefied natural gas (LNG) vaporizes and evaporates. More specifically, liquefied natural gas is natural gas that is liquefied to 1 / 600 of its volume, stored, and then transported via ships. So-called LNG carriers are equipped with tanks for storing liquefied natural gas. An inert gas is injected into the interior of the tank to reduce the risk of explosion. When the liquefied natural gas is stored in the tank in a liquid state and transported, heat penetration occurs into the tank, causing the liquefied natural gas to vaporize and evaporate. Such gas is called boil-off gas (BOG). The boil-off gas mixes with the inert gas to form a mixed gas, and since this mixed gas causes problems for the treatment of liquefied gas, it must be discharged to the outside and burned. The present invention relates to a combustion device for burning boil-off gas.

[0025] Referring to FIG. 1, an evaporative gas combustion device according to an embodiment of the present invention relates to a combustion device for burning evaporative gas that has been vaporized and evaporated from liquefied natural gas, and comprises an evaporative gas supply unit (10), an external air unit (20), and an ignition unit (30).

[0026] The above-mentioned evaporative gas supply unit (10) is configured to supply evaporative gas and includes a main body unit (11) and a cover unit (12). The main body unit (11) includes an inlet unit (111) into which the evaporative gas is introduced and an outlet unit (112) into which the introduced evaporative gas is discharged. The evaporative gas introduced into the main body unit (11) may be in a form mixed with the inert gas.

[0027] According to an embodiment of the present invention, the main body (11) is formed as a cylindrical shape with a closed top, the inlet (111) is provided at the bottom, and the outlet (112) is provided along the circumferential direction of the side. Specifically, the outlet (112) includes a plurality of outlet holes (113) formed around the circumference of the main body (11). Evaporated gas introduced into the interior of the main body (11) is discharged radially outward through the plurality of outlet holes (113).

[0028] According to the present embodiment, the discharge holes (113) are spaced apart from each other in the vertical direction and arranged side by side to form a row, and a plurality of rows are formed in the circumferential direction of the main body (11). That is, a plurality of rows of discharge holes (113) are arranged in the vertical direction, spaced apart from each other at a certain distance in the circumferential direction of the main body (11).

[0029] Additionally, the discharge hole (113) is formed horizontally or downwardly inclined on the inner surface of the evaporative gas supply unit (10) so that the evaporative gas is sprayed horizontally or downwardly inclined. According to the present embodiment, the discharge hole (113) is formed horizontally or downwardly inclined such that a virtual line penetrating the center of the discharge hole (113) extends horizontally from the outer surface of the main body (11) or is formed downwardly from the horizontal direction at an angle greater than 0° and less than 3°. The discharge hole (113) ejects the evaporative gas horizontally or downwardly to facilitate ignition by the ignition unit (30). Since external air from the external air supply unit (20) is discharged upwardly, when the evaporative gas sprayed through the discharge hole (113) is sprayed horizontally or downwardly, it provides the effect of increasing the concentration of the evaporative gas near the ignition unit (30), thereby facilitating ignition. If the angle of the evaporated gas sprayed from the discharge port (113) exceeds 3° downward, it hinders the upward flow of the rising external air and thus hinders the flame from flowing upward, so it is preferable that the evaporated gas be sprayed downward within the angle range mentioned above.

[0030] The above cover portion (12) covers the upper surface of the main body portion (11). Evaporated gas introduced through the inlet of the main body portion (11) rises upward, then hits the cover portion (12) and is guided to the side, and is discharged to the outside through the discharge hole (113) formed on the side.

[0031] The above-mentioned external air supply unit (20) is arranged around the evaporative gas supply unit (10) to spray external air upward. The external air creates an atmosphere for ignition and combustion by supplying oxygen to the evaporative gas. According to the present embodiment, the external air supply unit (20) includes an upper plate (21) and a side plate (23).

[0032] The upper plate (21) is a disc-shaped member having a mounting hole formed in the center for mounting the evaporative gas supply unit (10). The diameter of the mounting hole is formed to correspond to the diameter of the main body (11). The main body (11) can be connected to the upper plate (21) by a bolt. Since the main body (11) is detachably connected to the upper plate (21) by a bolt, the repair and replacement of the main body (11) can be facilitated. In an embodiment of the present invention, the diameter of the upper plate (21) is formed to be larger than the diameter of the main body (11), and a first injection hole (211) is formed in the upper plate (21) at a certain distance from the center on the circumference of a virtual circle having a first diameter.

[0033] Additionally, a second injection hole (212) is formed at a certain interval on the circumference of a virtual circle having a second diameter larger than the first diameter. The first and second injection holes (211, 212) are provided to eject external air. Accordingly, according to the present embodiment, the external air is ejected upward through the first and second injection holes (211, 212).

[0034] Additionally, a guide member (25) communicating with the mounting hole is coupled to the lower side of the upper plate (21). The guide member (25) is formed in a cylindrical shape to guide the evaporated gas into the interior of the main body (11).

[0035] The reinforcing member (22) is provided to be coupled to the lower part of the upper plate (21) to support the upper plate (21). A plurality of reinforcing members (22) are arranged spaced apart in the circumferential direction on the lower side of the upper plate (21). One end of the reinforcing member (22) is coupled to the side plate (23) described later. The reinforcing member (22) connects the upper plate (21) and the side plate (23) to increase structural rigidity.

[0036] The above side plate (23) has its upper end connected to the circumference of the above top plate (21) and extends downward to form a band shape. The above side plate (23) and the above top plate (21) are approximately open downward based on their cross-sections. It is formed in the shape of ", and the space formed by the side plate (23) and the top plate (21) forms a space into which outside air is introduced. That is, the side plate (23) surrounds the perimeter of the top plate (21) to form a space into which outside air is introduced.

[0037] The ignition unit (30) is arranged along the circumferential direction of the evaporative gas supply unit (10), and a plurality of them are provided. According to the present embodiment, the ignition unit (30) is coupled to the upper plate (21) of the external air supply unit (20) along the outer circumferential direction of the main body (11). According to the present embodiment, eight ignition units (30) are provided. Of course, the number of ignition units (30) is not limited thereto.

[0038] According to the present embodiment, the ignition unit (30) is provided on the upper surface of the upper plate (21) between the virtual circle of the first diameter and the outer surface of the main body (11). That is, the distance from the center of the main body (11) to the ignition unit (30) is shorter than the distance from the center of the main body (11) to the first injection hole (211). Since the evaporated gas flows laterally from the discharge hole (113), when ignited by the ignition unit (30), the evaporated gas flows laterally and mixes with the external air discharged upward through the first injection hole (211), thereby facilitating ignition and combustion.

[0039] According to the present embodiment, the ignition unit (30) is formed in a number corresponding to the number of rows of exhaust holes (113) formed in the main body (11). In another embodiment, the ignition unit (30) may be installed in a number different from the number of rows. Additionally, the ignition unit (30) faces the exhaust hole (113) located at the bottom of the row. Ignition is facilitated by using the evaporated gas discharged from the exhaust hole (113) located at the bottom of the row.

[0040] Additionally, according to an embodiment of the present invention, the lowest exhaust hole (113) includes a plurality of sub-exhaust holes (114) having a diameter smaller than that of the exhaust hole (113) positioned above it in the same row. The sub-exhaust holes (114) perform the function of dispersing the evaporated gas near the ignition unit (30), thereby increasing the contact area with rising external air and providing the effect of improving ignition efficiency. Of course, in other embodiments, the size of the exhaust holes (113) may all be formed to be the same.

[0041] An evaporative gas combustion device according to an embodiment of the present invention includes a chamber part (40) and a mounting bracket (24).

[0042] The chamber section (40) is a space where the evaporated gas discharged through the exhaust port (113) and the external air ejected through the external air supply section (20) are mixed and combusted. The flame of the evaporated gas, ignited and combusted by the evaporated gas supply section (10), rises upward into the chamber section (40).

[0043] The mounting bracket (24) is formed to protrude from the perimeter of the side plate (23) of the external air supply unit (20) so as to be detachably coupled to a fastening part formed on the lower side of the chamber part (40). The mounting bracket (24) and the fastening part are bolted together so as to be detachably coupled to each other, allowing for easy replacement when it is necessary to replace the evaporative gas supply unit (10) and the external air supply unit (20).

[0044] Hereinafter, the operation or effect of the evaporative gas combustion device according to the above configuration will be explained in detail.

[0045] Evaporated gas is generated from a tank storing liquefied natural gas (LNG). Additionally, to prevent the explosion of the liquefied natural gas, an inert gas is injected, so that the evaporated gas exists as a mixed gas in which the inert gas is mixed, and the evaporated gas is discharged to the outside of the tank and combusted by a combustion device according to the present invention.

[0046] The above evaporated gas is introduced into the main body (11) through the inlet (111), and the evaporated gas collides with the cover (12) coupled to the upper part of the main body (11), disperses to the side, and is ejected to the outside of the main body (11) through the discharge (112). The discharge (112) is composed of discharge holes (113) provided on the cylindrical outer surface of the main body (11), and the discharge holes (113) are provided in a plurality of rows arranged in the vertical direction. In addition, the discharge hole (113) provided at the bottom of each row is formed to include a sub-discharge hole (114) having a smaller diameter than other discharge holes (113) provided in the same row, thereby providing the effect of the evaporated gas discharged through the sub-discharge hole (114) having a dispersed flow rate and being sprayed outward.

[0047] The above external air supply unit (20) is for supplying external air to be mixed with the above evaporated gas, and the external air is introduced into the space formed by the top plate (21) and the side plate (23), and is discharged upward through the first and second injection holes (211, 212) provided in the top plate (21). Accordingly, the external air is discharged upward through the first injection hole (211) and the second injection hole (212), and the evaporated gas is sprayed from the main body (11) in a horizontal direction or at an angle greater than 0° and less than 3°, so that the rising external air and the evaporated gas are smoothly mixed and can be ignited by the ignition unit (30).

[0048] The ignition unit (30) is provided in the circumferential direction of the upper plate (21) of the external air supply unit (20), so as to evenly ignite the evaporated gas sprayed from the outer surface of the main body (11), and provides the effect of significantly improving ignition efficiency even if the evaporated gas contains inert gas. The evaporated gas ignited by the ignition unit (30) flows upward while burning in the chamber unit (40) and is discharged to the upper side of the chamber unit (40). A heat exchanger that exchanges heat using the combustion heat of the evaporated gas may be installed in the chamber unit (40).

[0049] Thus, the present invention provides the effect of smoothly performing combustion of evaporative gas to prevent unburned evaporative gas from being discharged into the atmosphere, and improving the ignition efficiency for combustion of evaporative gas even when a large amount of inert gas is contained.

[0050] Although the present invention has been described in detail with reference to preferred embodiments, the invention is not limited to the above embodiments, and many variations may be provided within the scope of the invention. Explanation of the symbols

[0051] 10... Evaporative Gas Supply Unit 11... Main Body Unit 12... Cover section 111... Inlet section 112... discharge section 113... discharge port 114... Sub-exhaust port 20... Outdoor air supply section 21... Top plate 22... Reinforcing member 23... Side panel section 211... 1st injection hole 212... 2nd injection hole 24... mounting bracket 25... Guide missing 30... Ignition part 40... chamber section

Claims

Claim 1 In a combustion device for burning evaporated gas that has been vaporized from liquefied natural gas, the device comprises: a main body (11) having an inlet (111) into which the evaporated gas is introduced and an outlet (112) into which the introduced evaporated gas is discharged, and a cover (12) covering the upper surface of the main body (11); and an external air supply unit (20) disposed around the evaporated gas supply unit (10) and spraying external air upward. The apparatus comprises a plurality of ignition units (30) arranged along the circumferential direction of the evaporative gas supply unit (10); wherein the main body (11) of the evaporative gas supply unit (10) is formed in a cylindrical shape, and the discharge unit (112) includes a plurality of discharge holes (113) formed around the circumferential direction of the main body (11), so that the evaporative gas introduced into the interior of the main body (11) is discharged radially outward through the discharge holes (113), and the discharge holes (113) are spaced apart from each other in the vertical direction and arranged side by side to form a row, and the row is formed in a plurality around the circumferential direction of the main body (11), and the ignition units (30) are formed in a number corresponding to the number of rows, and the discharge hole (113) located at the bottom of the row faces the ignition unit (30), and the bottom discharge hole (113) has a diameter smaller than the diameter of the discharge hole (113) arranged above it, and a plurality The external air supply unit (20) includes a sub-discharge port (114), and comprises: a disc-shaped top plate (21) having a mounting hole formed in the center for mounting the evaporative gas supply unit (10); and a side plate (23) having an upper end connected to the circumference of the top plate (21) and extending downward to form a band shape.An evaporative gas combustion device comprising: a first injection hole (211) disposed on the circumference of a virtual circle having a first diameter from the center of the top plate (21) to eject external air, and a second injection hole (212) disposed on the circumference of a virtual circle having a diameter larger than the first diameter to eject external air; wherein the ignition part (30) is provided on the upper surface of the top plate (21) between the virtual circle of the first diameter and the outer circumference of the main body (11). Claim 2 delete Claim 3 An evaporative gas combustion device according to claim 1, wherein the discharge hole (113) is formed horizontally or downwardly inclined on the inner surface of the evaporative gas supply unit (10) so as to spray the evaporative gas in a horizontal direction or downwardly inclined manner. Claim 4 delete Claim 5 delete Claim 6 An evaporative gas combustion device according to claim 3, wherein a virtual line penetrating the center of the discharge hole (113) is formed extending horizontally from the outer surface of the main body (11) or extending downward from the horizontal direction at an angle greater than 0° and less than or equal to 3°. Claim 7 An evaporative gas combustion device according to claim 3, comprising a chamber section (40) in which evaporative gas discharged through the discharge port (113) and outside air ejected through the outside air supply section (20) are mixed and combusted, and wherein a plurality of mounting brackets (24) are formed protruding from the perimeter of the side plate section (23) of the outside air supply section (20) and detachably coupled to a fastening section formed on the lower side of the chamber section (40). Claim 8 A boil-off gas combustion device according to claim 1, characterized in that the boil-off gas contains an inerting gas for inducing inertia of the liquefied natural gas. Claim 9 An evaporative gas combustion device according to claim 1, characterized by including a reinforcing member (22) that is spaced out in the circumferential direction on the lower side of the upper plate (21) to be coupled to the lower part of the upper plate (21) and to support the upper plate (21).

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