Liquefied natural gas boil-off gas recycling device

Abstract

The utility model discloses a liquefied natural gas boil-off gas recycling device, which relates to the technical field of liquefied natural gas, and comprises a storage tank, a support column is fixedly connected below the storage tank, a compressor is arranged on one side above the storage tank, a suction end of the compressor is fixedly connected with a suction pipe, and the suction pipe is fixedly connected with a gas outlet of the storage tank. The output end of the compressor is fixedly connected with a refrigeration tank, a cooling device is arranged above the refrigeration tank, the end, away from the compressor, of the refrigeration tank is fixedly connected with a guide pipe, one side of the guide pipe is fixedly connected with a filter box, a filter device is arranged on the inner wall of the filter box, and one side of the filter box is fixedly connected with a discharge pipe. A filter box and a filter device are arranged, so that a filter screen can be replaced, and the practicability of the device is improved; and the refrigeration tank and the cooling device are arranged, so that the heat exchange area is increased, the cooling efficiency is improved, and the recovery efficiency of the evaporated gas is greatly improved.

Description

Technical Field

[0001] The utility model relates to the technical field of liquefied natural gas, in particular to a liquefied natural gas boil-off gas recovery device. Background Art

[0002] Liquefied natural gas (LNG) is a method of liquefying natural gas by lowering its temperature to approximately -162°C, thereby reducing its volume and facilitating storage and transportation. However, during storage and transportation, LNG may evaporate due to changes in ambient temperature, generating boil-off gas. If these boil-off gases are not properly handled, they will not only waste energy, but may also have an impact on the environment and safety.

[0003] For example, the Chinese patent with application number "CN202121206477.7" is named "A liquefied natural gas boil-off gas recovery device", which includes a liquefied natural gas storage tank, liquefied natural gas, a recovery mechanism and a pressure monitoring device. The bottom of the liquefied natural gas storage tank is welded with a support leg, and the support leg is fixedly connected to the anti-slip foot pad. The liquefied natural gas is arranged inside the liquefied natural gas storage tank, and a boil-off gas is arranged above the liquefied natural gas. The recovery mechanism is arranged above the boil-off gas, and a filtering mechanism is arranged above the recovery mechanism. The pressure monitoring device is arranged on one side of the liquefied natural gas storage tank, and a control system is arranged above the pressure monitoring device. The liquefied natural gas boil-off gas recovery device is provided with a recovery mechanism and a filtering mechanism. The recovery mechanism facilitates the recovery of liquefied natural gas boil-off gas, and the filtering mechanism facilitates the filtering treatment of liquefied natural gas to avoid direct discharge into the air that will pollute the environment. This method is relatively simple and easy to use.

[0004] The device cannot replace the filter mechanism during long-term use, which reduces the flexibility of the device. Secondly, the device liquefies the evaporated gas through a condensing heat exchanger, but the refrigeration efficiency is not high and the evaporated gas cannot be completely and effectively liquefied. Utility Model Content

[0005] In view of the shortcomings of the prior art, the utility model provides a liquefied natural gas evaporated gas recovery device. By providing a filter box and a filter device, the filter screen can be replaced, thereby improving the practicality of the device; a refrigeration tank and a cooling device are provided to increase the heat exchange area, improve the cooling efficiency, and greatly improve the evaporated gas recovery efficiency.

[0006] The utility model also provides a recycling device for liquefied natural gas evaporated gas, comprising: a storage tank, a support column fixedly connected to the bottom of the storage tank, a compressor arranged on one side of the top of the storage tank, a suction pipe fixedly connected to the suction end of the compressor, a refrigeration tank fixedly connected to the output end of the compressor, a cooling device arranged on the top of the refrigeration tank, a conduit fixedly connected to the end of the refrigeration tank away from the compressor, a filter box fixedly connected to one side of the conduit, a filter device arranged on the inner wall of the filter box, and a discharge pipe fixedly connected to one side of the filter box. By providing the filter box and the filter device, the filter screen can be replaced, thereby improving the practicality of the device; by providing the refrigeration tank and the cooling device, the heat exchange area is increased, the cooling efficiency is improved, and the recovery efficiency of the evaporated gas is greatly improved.

[0007] According to the device for recovering evaporated gas of liquefied natural gas, the cooling device comprises a refrigeration box fixedly connected to the top of a refrigeration tank, a water pump is fixedly connected to one side of the refrigeration box, a circulation pipe is fixedly connected to the output end of the water pump, one end of the circulation pipe passing through the refrigeration tank is fixedly connected to a refrigeration pipe, and the end of the refrigeration pipe away from the circulation pipe is fixedly connected to a return pipe.

[0008] According to the liquefied natural gas evaporated gas recovery device, the filtering device comprises a slide groove provided on one side of the filter box, a bracket is slidably connected in the slide groove, and a plurality of filter screens are snap-connected to the inner wall of the bracket.

[0009] According to the liquefied natural gas boil-off gas recovery device, the refrigeration pipe is spiral in shape, and one end of the refrigeration pipe passes through the refrigeration tank and is fixedly connected to one side of the refrigeration box.

[0010] According to the liquefied natural gas boil-off gas recovery device, a handle is fixedly connected to one side of the bracket, and a sealing gasket is provided at the connection between the bracket and the slide groove.

[0011] According to the liquefied natural gas boil-off gas recovery device, control valves are provided above the suction pipe, the conduit and the discharge pipe.

[0012] According to the liquefied natural gas boil-off gas recovery device, there are three support columns, and the three support columns are symmetrically distributed.

[0013] Additional aspects and advantages of the present invention will be given in part in the following description, and in part will become apparent from the following description, or will be learned through the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The utility model is further described below in conjunction with the accompanying drawings and embodiments;

[0015] Figure 1 It is a side-view stereoscopic diagram of a liquefied natural gas boil-off gas recovery device of the utility model;

[0016] Figure 2 This is a front perspective view of a liquefied natural gas boil-off gas recovery device of the utility model;

[0017] Figure 3 It is a three-dimensional diagram from the rear perspective of a liquefied natural gas boil-off gas recovery device of the utility model;

[0018] Figure 4 The utility model is a schematic diagram of the internal structure of a refrigeration tank of a liquefied natural gas boil-off gas recovery device.

[0019] Legend:

[0020] 1. Storage tank; 2. Support column; 3. Compressor; 4. Suction pipe; 5. Refrigeration tank; 6. Cooling device; 7. Conduit; 8. Filter box; 9. Filter device; 10. Discharge pipe; 601. Refrigeration box; 602. Water pump; 603. Circulation pipe; 604. Refrigeration pipe; 605. Refrigeration pipe; 901. Slide; 902. Bracket; 903. Filter; 9021. Handle. DETAILED DESCRIPTION

[0021] This section will describe in detail the specific embodiments of the utility model. The preferred embodiments of the utility model are shown in the accompanying drawings. The purpose of the accompanying drawings is to supplement the description of the text part of the specification with graphics, so that people can intuitively and vividly understand each technical feature and the overall technical solution of the utility model, but it cannot be understood as a limitation on the protection scope of the utility model.

[0022] Reference Figure 1-4 The utility model discloses a device for recovering evaporated gas of liquefied natural gas, which comprises a storage tank 1, a support column 2 is fixedly connected to the bottom of the storage tank 1, the number of the support columns 2 is three, and the three support columns 2 are symmetrically distributed, the stability of the storage tank 1 is improved by the support columns 2, a compressor 3 is arranged on the upper side of the storage tank 1, a suction pipe 4 is fixedly connected to the suction end of the compressor 3, a refrigeration tank 5 is fixedly connected to the output end of the compressor 3, a cooling device 6 is arranged above the refrigeration tank 5, a conduit 7 is fixedly connected to the end of the refrigeration tank 5 away from the compressor 3, a filter box 8 is fixedly connected to one side of the conduit 7, a filter device 9 is arranged on the inner wall of the filter box 8, a discharge pipe 10 is fixedly connected to one side of the filter box 8, and a control valve is arranged above the suction pipe 4, the conduit 7 and the discharge pipe 10.

[0023] The cooling device 6 includes a refrigeration box 601 fixedly connected to the top of the refrigeration tank 5, a water pump 602 is fixedly connected to one side of the refrigeration box 601, a circulation pipe 603 is fixedly connected to the output end of the water pump 602, the circulation pipe 603 passes through the refrigeration tank 5 and is fixedly connected to a refrigeration pipe 604 at one end, the refrigeration pipe 604 is spiral in shape, and the end of the refrigeration pipe 604 away from the circulation pipe 603 is fixedly connected to a return pipe 605, one end of the return pipe 605 passes through the refrigeration tank 5 and is fixedly connected to one side of the refrigeration box 601.

[0024] The filter device 9 includes a chute 901 provided on one side of the filter box 8, a bracket 902 is slidably connected in the chute 901, a handle 9021 is fixedly connected to one side of the bracket 902, and a sealing gasket is provided at the connection between the bracket 902 and the chute 901, and a plurality of filter nets 903 are engaged and connected to the inner wall of the bracket 902. By providing the filter box 8 and the filter device 9, the filter nets 903 can be replaced, thereby improving the practicality of the device; by providing the refrigeration tank 5 and the cooling device 6, the heat exchange area is increased, the cooling efficiency is improved, and the recovery efficiency of the evaporated gas is greatly improved.

[0025] Working principle: When used for the first time, the storage tank 1 is used to store liquefied natural gas LNG. During the storage process, due to the influence of the ambient temperature, LNG will produce evaporated gas. The evaporated gas of LNG in the storage tank 1 is extracted through the suction end output suction pipe 4 of the compressor 3. The compressor 3 compresses the evaporated gas and inputs it into the refrigeration tank 5. When the water pump 602 is started, water is pumped from the refrigeration box 601 and output to the circulation pipe 603 and passes through the refrigeration pipe 604 and the return pipe 605, so that the refrigeration water circulates. At the same time, the refrigeration pipe 604 is spirally shaped to greatly increase the heat exchange area and improve the cooling efficiency, so that the evaporated gas is liquefied. The liquefied LNG is transported to the filter box 8 through the conduit 7. The multiple filter screens 903 in the filter box 8 are filtered and then the filtered liquefied natural gas is discharged into the storage tank 1 through the discharge pipe 10. Secondly, when the filter screen 903 needs to be cleaned, the handle 9021 can be pulled to pull the bracket 902 out of the filter box 8, so as to facilitate the cleaning or replacement of the filter screen.

[0026] The embodiments of the present invention are described in detail above in conjunction with the accompanying drawings, but the present invention is not limited to the above embodiments, and various changes can be made within the knowledge scope of ordinary technicians in the relevant technical field without departing from the purpose of the present invention.

Claims

1. A liquefied natural gas boil-off gas recovery device, comprising: A storage tank (1), characterized in that a support column (2) is fixedly connected to the bottom of the storage tank (1), a compressor (3) is arranged on one side above the storage tank (1), a suction end of the compressor (3) is fixedly connected to a suction pipe (4), an output end of the compressor (3) is fixedly connected to a refrigeration tank (5), a cooling device (6) is arranged above the refrigeration tank (5), an end of the refrigeration tank (5) away from the compressor (3) is fixedly connected to a conduit (7), one side of the conduit (7) is fixedly connected to a filter box (8), an inner wall of the filter box (8) is provided with a filter device (9), and one side of the filter box (8) is fixedly connected to a discharge pipe (10).

2. A liquefied natural gas boil-off gas recovery device according to claim 1, characterized in that: The cooling device (6) comprises a refrigeration box (601) fixedly connected to the top of the refrigeration tank (5); a water pump (602) is fixedly connected to one side of the refrigeration box (601); an output end of the water pump (602) is fixedly connected to a circulation pipe (603); one end of the circulation pipe (603) passing through the refrigeration tank (5) is fixedly connected to a refrigeration pipe (604); and one end of the refrigeration pipe (604) away from the circulation pipe (603) is fixedly connected to a return pipe (605).

3. The liquefied natural gas boil-off gas recovery device according to claim 1, characterized in that: The filtering device (9) comprises a slide groove (901) arranged on one side of the filter box (8), a bracket (902) is slidably connected in the slide groove (901), and a plurality of filter screens (903) are snap-connected to the inner wall of the bracket (902).

4. A liquefied natural gas boil-off gas recovery device according to claim 2, characterized in that: The refrigeration pipe (604) is in a spiral shape, and one end of the return pipe (605) passes through the refrigeration tank (5) and is fixedly connected to one side of the refrigeration box (601).

5. The liquefied natural gas boil-off gas recovery device according to claim 3, characterized in that: A handle (9021) is fixedly connected to one side of the bracket (902), and a sealing gasket is provided at the connection between the bracket (902) and the slide groove (901).

6. The liquefied natural gas boil-off gas recovery device according to claim 1, characterized in that: Control valves are arranged above the suction pipe (4), the conduit (7) and the discharge pipe (10).

7. The liquefied natural gas boil-off gas recovery device according to claim 1, characterized in that: The number of the support columns (2) is three, and the three support columns (2) are symmetrically distributed.

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