CN214369276U

CN214369276U - BOG recycling system of LNG gas station

Info

Publication number: CN214369276U
Application number: CN202120565677.5U
Authority: CN
Inventors: 黄中峰; 秦雯; 左鑫; 张驿; 程德才; 邹建鑫
Original assignee: Chongqing Xingran Energy Co ltd; Chongqing Gas Group Co ltd
Current assignee: Chongqing Xingran Energy Co ltd; Chongqing Gas Group Co ltd
Priority date: 2021-03-19
Filing date: 2021-03-19
Publication date: 2021-10-08
Anticipated expiration: 2031-03-19

Abstract

The utility model discloses a LNG gas station BOG recycle system, keep in jar, compressor, vapour and liquid separator, LNG tank wagon and LNG storage tank including BOG, BOG keeps in the jar and is connected with BOG input pipeline, compressor pipeline, municipal pipe network pipeline and tank wagon pipeline. By adopting the technical scheme, the temporary storage tank of the BOG is additionally arranged, so that part of the collected BOG can be used for pressurizing the LNG tank wagon, the LNG can be completely unloaded into the LNG storage tank, the BOG is effectively utilized, and the unloading rate of the LNG is improved; one part of the gas is directly conveyed into a municipal pipe network to supply municipal gas; the rest part is conveyed to the compressor, is pressurized and converted into LNG, and is separated out residual BOG through the gas-liquid separator, and finally pure LNG is conveyed back to the LNG storage tank, so that the load of the compressor is greatly reduced, the energy consumption of a BOG recycling system is reduced, the electricity charge is saved, the maintenance period of the compressor is greatly prolonged, and the maintenance cost is reduced.

Description

BOG recycling system of LNG gas station

Technical Field

The utility model relates to a LNG gas station equipment technical field, concretely relates to LNG gas station BOG recycle system.

Background

Liquefied Natural Gas (LNG) is an alternative energy source of fossil energy, and has the characteristics of high transportation and storage efficiency, low temperature and easiness in evaporation. Low-temperature boil-off gas (BOG) may be generated during LNG storage, transportation, loading and unloading, which may cause a pressure increase in the LNG storage tank, resulting in resource waste and environmental pollution.

Therefore, more and more LNG gas stations begin to set up BOG recovery system at present, utilize the compressor with BOG liquefaction for LNG once more to carry back to in the LNG storage tank, in order to realize BOG's recovery and recycle, avoid direct evacuation to cause the problem of wasting of resources and environmental pollution.

However, in the conventional BOG recovery system, it is found that the compressor needs to continuously perform a high-load operation in actual operation, which results in not only a large amount of power consumption and a large electricity cost, but also a short maintenance cycle and a high maintenance cost of the compressor. Therefore, the operation effect of the existing BOG recovery system is not ideal all the time.

And, when the LNG tank wagon unloads the gas operation at LNG gas station, in the later stage of unloading, because the LNG tank wagon self pressure reduce to being less than the LNG storage tank of gas station, lead to the LNG tank wagon can not unload LNG into the LNG storage tank completely.

It is urgent to solve the above problems.

SUMMERY OF THE UTILITY MODEL

For the technical problem who solves, the utility model provides a BOG recycle system of LNG gas station.

The technical scheme is as follows:

a BOG recycling system of an LNG gas station is characterized by comprising a BOG temporary storage tank, a compressor, a gas-liquid separator, an LNG tank car and an LNG storage tank, wherein the BOG temporary storage tank is connected with a BOG input pipeline, a compressor conveying pipeline, a municipal pipe network conveying pipeline and a tank car conveying pipeline;

the BOG input pipeline is used for inputting BOG into the BOG temporary storage tank;

the compressor conveying pipeline is connected with the compressor and is used for conveying BOG to the compressor;

the municipal pipe network conveying pipeline is connected with the municipal pipe network interface and is used for conveying BOG to the municipal pipe network;

the tank wagon conveying pipeline is connected with the LNG tank wagon, and is used for conveying BOG to the LNG tank wagon to pressurize the LNG tank wagon, so that the LNG tank wagon can completely unload LNG into the LNG storage tank;

the compressor conveys LNG mixed with BOG to the gas-liquid separator through the compressor output pipeline, the gas-liquid separator conveys the separated BOG to the BOG input pipeline through the BOG return pipeline, and the gas-liquid separator conveys the separated LNG to the LNG storage tank through the LNG return pipeline.

By adopting the structure, the temporary storage tank of the BOG is additionally arranged, so that part of the collected BOG can be used for pressurizing the LNG tank wagon, the LNG can be completely unloaded into the LNG storage tank, the BOG is effectively utilized, and the unloading rate of the LNG is improved; one part of the gas is directly conveyed into a municipal pipe network to supply municipal gas; the rest part is conveyed to the compressor, is pressurized and converted into LNG, and is separated out residual BOG through the gas-liquid separator, and finally pure LNG is conveyed back to the LNG storage tank, so that the load of the compressor is greatly reduced, the energy consumption of a BOG recycling system is reduced, the electricity charge is saved, the maintenance period of the compressor is greatly prolonged, and the maintenance cost is reduced.

Preferably, the method comprises the following steps: the BOG input pipeline is connected with a storage tank BOG output pipeline connected with the LNG storage tank, an immersed pump BOG output pipeline connected with an immersed pump and a gas dispenser BOG output pipeline connected with each LNG gas dispenser. By adopting the structure, the BOG generated by heat absorption and gasification in the LNG storage tank and the BOG generated in the working process of the immersed pump and the LNG dispenser can be effectively recovered.

Preferably, the method comprises the following steps: the LNG storage tank delivers LNG to the immersed pump through the LNG output pipeline of the storage tank, and the immersed pump delivers LNG to each LNG dispenser through the LNG output pipeline of the immersed pump.

Preferably, the method comprises the following steps: and the compressor conveying pipeline and the compressor output pipeline are connected into the same heat exchanger, so that the compressor conveying pipeline precools the compressor output pipeline. By adopting the structure, the compressor delivery pipeline is utilized to pre-cool the compressor output pipeline, so that the load of the compressor can be effectively reduced, and the energy consumption is reduced.

Preferably, the method comprises the following steps: and a throttler is arranged on the output pipeline of the compressor and is positioned between the heat exchanger and the gas-liquid separator. By adopting the structure, the throttler can be matched with the gas-liquid separator to more thoroughly separate BOG in LNG.

Compared with the prior art, the beneficial effects of the utility model are that:

the BOG recycling system of the LNG gas station adopting the technical scheme has the advantages of novel structure, ingenious design and easy realization, and can pressurize an LNG tank car by using a part of collected BOG through additionally arranging the BOG temporary storage tank, so that LNG can be completely unloaded into the LNG storage tank, the BOG is effectively utilized, and the unloading rate of the LNG is improved; one part of the gas is directly conveyed into a municipal pipe network to supply municipal gas; the rest part is conveyed to the compressor, is pressurized and converted into LNG, and is separated out residual BOG through the gas-liquid separator, and finally pure LNG is conveyed back to the LNG storage tank, so that the load of the compressor is greatly reduced, the energy consumption of a BOG recycling system is reduced, the electricity charge is saved, the maintenance period of the compressor is greatly prolonged, and the maintenance cost is reduced.

Drawings

Fig. 1 is a schematic view of the present invention.

Detailed Description

The present invention will be further described with reference to the following examples and accompanying drawings.

As shown in fig. 1, a BOG recycling system for an LNG refueling station mainly includes a BOG temporary storage tank 1, a compressor 3, a gas-liquid separator 4, an LNG tanker 5, and an LNG storage tank 22.

The BOG temporary storage tank 1 is connected with a BOG input pipeline 6, a compressor conveying pipeline 7, a municipal pipe network conveying pipeline 8 and a tank car conveying pipeline 9.

The BOG input pipeline 6 is used for inputting BOG into the BOG temporary storage tank 1, and the BOG input pipeline 6 is connected with the storage tank BOG output pipeline 14, the immersed pump BOG output pipeline 16 and the gas dispenser BOG output pipeline 18.

The BOG input pipeline 6 is connected to a storage tank BOG output pipeline 14 connected to the LNG storage tank 22, an immersed pump BOG output pipeline 16 connected to the immersed pump 15, and a dispenser BOG output pipeline 18 connected to each LNG dispenser 17. The LNG storage tank 22 delivers LNG to the immersed pump 15 through the storage tank LNG export line 19, and the immersed pump 15 delivers LNG to each LNG dispenser 17 through the immersed pump LNG export line 20. Therefore, BOG generated in the LNG storage tank 22, BOG generated when the immersed pump 15 works and BOG generated when the LNG dispenser 17 works are respectively converged into the BOG input pipeline 6 through the storage tank BOG output pipeline 14, the immersed pump BOG output pipeline 16 and the dispenser BOG output pipeline 18, and finally conveyed into the BOG temporary storage tank 1 from the BOG input pipeline 6.

Municipal pipe network pipeline 8 and municipal pipe network interface 2 are connected, and municipal pipe network pipeline 8 is used for carrying BOG to the municipal pipe network, and consequently, BOG in the BOG jar of keeping in 1 can carry for the municipal pipe network through municipal pipe network pipeline 8.

Tanker transport line 9 is connected with LNG tanker 5, tanker transport line 9 is used to transport BOG to LNG tanker 5 to pressurize LNG tanker 5 so that LNG tanker 5 can completely discharge LNG into LNG storage tank 22. Therefore, the BOG in the BOG temporary storage tank 1 can be transported to the LNG tanker 5 through the tanker transport line 9, so as to pressurize the LNG tanker 5, so that the pressure of the LNG tanker 5 is always greater than the pressure of the LNG storage tank 22, and finally the LNG of the LNG tanker 5 can be completely discharged to the LNG storage tank 22.

Compressor conveying line 7 is connected with compressor 3, BOG in BOG temporary storage tank 1 can carry BOG to compressor 3 through compressor conveying line 7, compressor 3 compresses BOG into LNG, then, compressor 3 will be mixed in BOG's LNG and carry in vapour and liquid separator 4 through compressor output pipeline 10, vapour and liquid separator 4 carries BOG that separates to BOG input line 6 through BOG return line 11 in, vapour and liquid separator 4 carries LNG that separates to LNG storage tank 22 through LNG return line 12. It should be noted that the same heat exchanger 13 is connected to both the compressor conveying pipeline 7 and the compressor output pipeline 10, so that the compressor conveying pipeline 7 precools the compressor output pipeline 10, that is, the temperature of the compressor output pipeline 10 is very low due to the fact that LNG is conveyed, and BOG in the compressor conveying pipeline 7 can be precooled through the heat exchanger 13, so that the compressor 3 can compress BOG into LNG with lower power consumption.

Furthermore, a restrictor 21 is arranged on the compressor output pipeline 10, the restrictor 21 is positioned between the heat exchanger 13 and the gas-liquid separator 4, and the restrictor 21 throttles the LNG in the compressor output pipeline 10, so that the BOG in the LNG can be more thoroughly separated in cooperation with the gas-liquid separator 4.

Finally, it should be noted that the above description is only a preferred embodiment of the present invention, and those skilled in the art can make various similar representations without departing from the spirit and the scope of the present invention.

Claims

1. The utility model provides a BOG recycle system of LNG gas station which characterized in that: the BOG temporary storage tank system comprises a BOG temporary storage tank (1), a compressor (3), a gas-liquid separator (4), an LNG tank car (5) and an LNG storage tank (22), wherein the BOG temporary storage tank (1) is connected with a BOG input pipeline (6), a compressor conveying pipeline (7), a municipal pipe network conveying pipeline (8) and a tank car conveying pipeline (9);

the BOG input pipeline (6) is used for inputting BOG into the BOG temporary storage tank (1);

the compressor conveying pipeline (7) is connected with the compressor (3), and the compressor conveying pipeline (7) is used for conveying BOG to the compressor (3);

the municipal pipe network conveying pipeline (8) is connected with the municipal pipe network interface (2), and the municipal pipe network conveying pipeline (8) is used for conveying BOG to a municipal pipe network;

the tanker transport pipeline (9) is connected with the LNG tanker (5), and the tanker transport pipeline (9) is used for transporting BOG to the LNG tanker (5) to pressurize the LNG tanker (5), so that the LNG tanker (5) can completely unload LNG into the LNG storage tank (22);

the compressor (3) conveys LNG mixed with BOG to the gas-liquid separator (4) through the compressor output pipeline (10), the gas-liquid separator (4) conveys the separated BOG to the BOG input pipeline (6) through the BOG return pipeline (11), and the gas-liquid separator (4) conveys the separated LNG to the LNG storage tank (22) through the LNG return pipeline (12).

2. The BOG recycling system of the LNG filling station of claim 1, characterized in that: the BOG input pipeline (6) is connected with a storage tank BOG output pipeline (14) connected with the LNG storage tank (22), an immersed pump BOG output pipeline (16) connected with an immersed pump (15) and gas dispenser BOG output pipelines (18) connected with the LNG gas dispensers (17).

3. The BOG recycling system of the LNG filling station of claim 2, wherein: the LNG storage tank (22) is used for conveying LNG to the immersed pump (15) through the storage tank LNG output pipeline (19), and the immersed pump (15) is used for conveying LNG to each LNG filling machine (17) through the immersed pump LNG output pipeline (20).

4. The BOG recycling system of the LNG filling station of claim 1, characterized in that: the compressor conveying pipeline (7) and the compressor output pipeline (10) are connected into the same heat exchanger (13) so that the compressor conveying pipeline (7) precools the compressor output pipeline (10).

5. The BOG recycling system of the LNG filling station of claim 4, wherein: the compressor output pipeline (10) is provided with a throttler (21), and the throttler (21) is positioned between the heat exchanger (13) and the gas-liquid separator (4).