KR102299354B1 - Gas treatment system and ship having the same - Google Patents

Abstract

The present invention relates to a gas treatment system and a ship, comprising: a boil-off gas storage tank for storing boil-off gas generated from a liquefied gas storage tank to which liquefied gas is supplied during bunkering; and a boil-off gas heat exchanger cooling the boil-off gas delivered to the boil-off gas storage tank using liquefied gas supplied during bunkering, wherein the boil-off gas storage tank adsorbs and stores the boil-off gas using an adsorbent. characterized.

Description

Gas treatment system and ship having the same}

The present invention relates to a gas treatment system and a ship.

A ship is a means of transport that carries a large amount of minerals, crude oil, natural gas, or thousands of containers or more and sails the ocean. move through

These ships generate thrust by driving an engine or a gas turbine, etc. At this time, the engine uses fuel such as gasoline or diesel to move the piston so that the crankshaft rotates by the reciprocating motion of the piston, and the shaft connected to the crankshaft is It is rotated to drive the propeller, while gas turbines burn fuel with compressed air and use the temperature/pressure of the combustion air to rotate turbine blades to generate electricity and transmit power to the propellers.

However, recently, an LNG fuel supply method in which LNG is used as a fuel to drive a customer such as an engine or a turbine is used in an LNG carrier that transports liquefied natural gas. This method is also applied to ships other than LNG carriers.

In general, LNG is a clean fuel and is known to have more abundant reserves than petroleum, and its usage is rapidly increasing as mining and transport technologies are developed. In such LNG, methane, which is the main component, is generally stored in a liquid state by lowering the temperature to -162°C or less under 1 atm. The volume of liquefied methane is about 1/600 of the volume of gaseous methane in the standard state The specific gravity is 0.42, which is about one-half of that of crude oil.

However, the temperature and pressure required to drive the consumer may be different from the state of the LNG stored in the tank. Therefore, in recent years, continuous research and development has been made on a technology for supplying the LNG stored in a liquid state by controlling the temperature and pressure, and the like.

The present invention was created to solve the problems of the prior art as described above, and an object of the present invention is a gas treatment system and a ship that can secure storage efficiency while increasing stability through a method of adsorbing and storing gas on an adsorbent. is to provide

It is also an object of the present invention to provide a gas treatment system and a ship capable of realizing efficient storage and reuse of excess gas by adsorbing and storing the surplus gas remaining unconsumed in the demanding place on an adsorbent.

Another object of the present invention is to provide a gas treatment system and a ship capable of preventing waste of BOG by adsorbing and storing BOG generated when liquefied gas is supplied from a bunkering vessel to a gas propulsion vessel with an adsorbent. .

A gas treatment system according to an aspect of the present invention includes: a boil-off gas storage tank for storing boil-off gas generated from a liquefied gas storage tank to which liquefied gas is supplied during bunkering; and a boil-off gas heat exchanger cooling the boil-off gas delivered to the boil-off gas storage tank using liquefied gas supplied during bunkering, wherein the boil-off gas storage tank adsorbs and stores the boil-off gas using an adsorbent. characterized.

Specifically, it further includes a bunkering line connected from the bunkering tank to the liquefied gas storage tank for bunkering, and the boil-off gas heat exchanger may be provided on the bunkering line.

Specifically, the bunkering line may further include a bypass line provided to bypass the boil-off gas heat exchanger.

Specifically, a boil-off gas recovery line connected from the liquefied gas storage tank to the bunkering tank to recover the boil-off gas; and a boil-off gas delivery line branched from the boil-off gas recovery line and connected to the boil-off gas storage tank.

Specifically, a boil-off gas sensor provided in the boil-off gas recovery line or the boil-off gas delivery line to measure the temperature of the boil-off gas; and a bypass valve provided on the bypass line, wherein an opening degree of the bypass valve may be adjusted according to the temperature of the boil-off gas measured by the boil-off gas sensor.

Specifically, it may further include a compressor provided in the boil-off gas recovery line or the boil-off gas delivery line to compress the boil-off gas discharged from the liquefied gas storage tank.

Specifically, the compressor may adjust the pressure for compressing the boil-off gas according to the storage amount of the boil-off gas storage tank.

A ship according to an aspect of the present invention is characterized in that it has the gas treatment system.

The gas treatment system and the ship according to the present invention can adsorb and store gas on an adsorbent, desorb the gas from the adsorbent and supply it to an engine, etc. have

In addition, the gas treatment system and the ship according to the present invention can be used by adsorbing surplus gas to the adsorbent and storing it, and then desorbing the surplus gas from the adsorbent when the gas is insufficient. By using heat exchange with , both efficiency and stability can be secured.

In addition, the gas treatment system and the ship according to the present invention can prevent the BOG generated during bunkering from being burned and discarded by adsorbing the BOG generated during bunkering to the adsorbent and storing it.

1 is a conceptual diagram of a gas processing system according to a first embodiment of the present invention.
2 is a conceptual diagram of a gas processing system according to a second embodiment of the present invention.
3 is a conceptual diagram of a gas processing system according to a third embodiment of the present invention.
4 is a conceptual diagram of a gas processing system according to a fourth embodiment of the present invention.

The objects, specific advantages and novel features of the present invention will become more apparent from the following detailed description and preferred embodiments taken in conjunction with the accompanying drawings. In the present specification, in adding reference numbers to the components of each drawing, it should be noted that only the same components are given the same number as possible even though they are indicated on different drawings. In addition, in describing the present invention, if it is determined that a detailed description of a related known technology may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be omitted.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. Hereinafter, a gas processing system of the present invention will be described, and the present invention includes a gas processing system and a ship having the same. In this case, it should be noted that a vessel is a general commercial vessel that does not limit the type of vessel, such as a container vessel, in addition to a liquefied gas carrier that loads liquefied gas, or is used to encompass all offshore plants such as FSRU and FLNG. In addition, the vessel may include a bunkering vessel for supplying liquefied gas to another vessel or land, etc. in addition to a vessel that is supplied to load or use liquefied gas as fuel.

Hereinafter, in this specification, liquefied gas may be used to encompass all gas fuels that are generally stored in a liquid state, such as LNG or LPG, ethylene, ammonia, etc., and boil-off gas (BOG) is naturally vaporized or It may mean forced vaporized liquefied gas. However, the boil-off gas may be used to include not only gaseous boil-off gas but also liquefied boil-off gas.

1 is a conceptual diagram of a gas processing system according to a first embodiment of the present invention.

Referring to FIG. 1 , the gas treatment system 1 according to the first embodiment of the present invention includes a gas storage tank 10 , a heat transfer unit 20 , and an oil storage tank 30 .

The gas storage tank 10 stores gas. The gas stored in the gas storage tank 10 may be natural gas, but the present invention is not particularly limited thereto.

The gas storage tank 10 adsorbs and stores the gas using an adsorbent. When the gas is natural gas, the gas storage tank 10 may store Absorbed Natural Gas (ANG). In this case, the adsorbent may be activated carbon or the like, and may be various materials that adsorb and store gas.

The gas adsorbed and stored in the gas storage tank 10 may be desorbed from the adsorbent and supplied to the engine 100 that is the consumer 100 . In this case, the engine 100 may be a propulsion engine 100 that consumes gas to generate power for propulsion of the vessel.

The pressure of the gas consumed by the engine 100 is not particularly limited, and may be a low pressure of 1 to 10 bar, a high pressure of 200 to 400 bar, or the like. Also, instead of the engine 100 , a turbine or city gas may be used as the demand 100 .

When the gas storage tank 10 stores gas using an adsorbent, the storage capacity may vary depending on the temperature. That is, since the gas may be more adsorbed to the adsorbent when the temperature is low, the storage capacity of the gas storage tank 10 may be increased when the temperature is decreased.

On the other hand, when the temperature increases, since the gas is about to be desorbed from the adsorbent, the storage capacity of the gas storage tank 10 may be reduced. The present embodiment may utilize the heat of the exhaust to desorb gas from the adsorbent by using this point.

In addition, in the gas storage tank 10, when the pressure increases, the storage capacity of the gas may increase, and when the pressure decreases, the storage capacity of the gas may decrease. Since the reduction in the storage capacity of the gas means that the gas is being desorbed from the adsorbent similarly to the case where the temperature is increased, the pressure of the gas storage tank 10 is reduced by using the gas discharge valve 16, etc., although this embodiment will be described later. It is possible to implement desorption of gas by lowering it.

A gas supply line 13 may be provided from the gas storage tank 10 to the engine 100 , and a compressor 11 and a heater 12 may be provided in the gas supply line 13 .

The compressor 11 may compress the gas desorbed from the adsorbent in the gas storage tank 10 and discharged. A plurality of compressors 11 may be provided, and may be arranged in series and/or in parallel. The number or arrangement of the compressor 11 may vary depending on the pressure required by the engine 100 , which is the customer 100 .

The heater 12 may be provided downstream of the compressor 11 to heat the compressed gas. The temperature of the gas heated by the heater 12 may be a temperature required by the engine 100 . At this time, the heater 12 may utilize various heat sources, for example, various waste heat (exhaust heat, waste heat generated from driving equipment, etc.) generated in the ship, steam, glycol water, seawater, etc. may be used.

A gas discharge line 14 may be provided in the gas storage tank 10 . The gas discharge line 14 is configured to discharge the gas contained in the gas storage tank 10 to the outside, and the internal pressure of the gas storage tank 10 may be lowered by the discharge of the gas.

As described above, when the pressure of the adsorbent of the gas storage tank 10 is lowered, the gas may be desorbed. Accordingly, when the internal pressure of the gas storage tank 10 is lowered while the gas is discharged by the gas discharge line 14 , the gas may be desorbed from the adsorbent.

A gas combustion device 15 is provided in the gas discharge line 14 to burn the gas discharged from the gas storage tank 10 . In addition, a gas discharge valve 16 is provided in the gas discharge line 14 , and the gas discharge valve 16 can adjust the flow rate of the gas discharged from the gas storage tank 10 through the gas discharge line 14 .

The gas discharge valve 16 may adjust the internal pressure of the gas storage tank 10 by adjusting the flow rate of the gas discharged from the gas storage tank 10 . This means controlling the amount of gas desorbed from the adsorbent in the gas storage tank 10 .

Therefore, in this embodiment, the internal pressure of the gas storage tank 10 can be lowered by using the gas discharge valve 16 so that the gas is smoothly transferred from the gas storage tank 10 to the engine 100 that is the demand 100 . have.

The heat transfer unit 20 transfers exhaust heat of the engine 100 to the gas storage tank 10 . If a separate operation (addition of heat, lowering of pressure, etc.) is not performed while the gas storage tank 10 adsorbs and stores gas, the gas discharged from the gas storage tank 10 meets the demand of the engine 100 . It may not be enough to make it happen.

Therefore, in the present embodiment, when the engine 100 is operated, it is possible to increase the flow rate of the gas desorbed from the adsorbent in the gas storage tank 10 and discharged by utilizing the exhaust heat of the engine 100 . To this end, the heat transfer unit 20 may include a heat recovery unit 21 and a heat transfer line 22 .

The heat recovery unit 21 recovers exhaust heat of the engine 100 . The heat recovery unit 21 may heat-exchange the exhaust with other heat sources to recover only the heat that the exhaust has, or recover the exhaust itself.

When the heat recovery unit 21 recovers the exhaust itself or when the heat is a material different from the adsorbent and gas stored in the gas storage tank 10 , the gas in the process of being delivered to the gas storage tank 10 by the heat recovery unit 21 . or contamination of the adsorbent may occur.

In order to solve this problem, the heat transfer line 22 may be provided in a structure in which the exhaust does not directly contact the adsorbent and the gas accommodated in the gas storage tank 10 . Of course, when the heat recovery unit 21 uses the same/similar material as gas or an adsorbent for heat exchange with exhaust, or uses a material that may be directly introduced into the gas storage tank 10, the heat transfer line 22 is It may be provided in a structure for supplying heat to the inside of the gas storage tank (10).

Of course, the present embodiment may not be limited to the structure or method in which exhaust heat is transferred to the gas storage tank 10 . However, in the present embodiment, as long as exhaust heat generated during operation of the engine 100 is used to desorb gas from the adsorbent in the gas storage tank 10 , any configuration may be employed.

In addition, in the present embodiment, the gas may be desorbed from the adsorbent by using the heat of the coolant used in the engine 100 together with or instead of the exhaust heat of the engine 100 . That is, in the present embodiment, various waste heats (exhaust heat, coolant heat, etc.) generated in the engine 100 can be utilized without limitation.

The engine 100 may be provided in plurality, and the engine 100 in which the heat transfer unit 20 recovers exhaust heat may not be the engine 100 that consumes the gas discharged from the gas storage tank 10 . . If the temperature of the gas storage tank 10 is low and the pressure is high, so that the desorption of the gas is not performed well, the operation of the engine 100 may be disturbed.

At this time, the heat transfer unit 20 transfers heat to the gas storage tank 10 using another engine 100 instead of the engine 100 driven by receiving gas from the gas storage tank 10 to desorb the gas. And it can be made to be discharged. Of course, as described above, the heat transfer unit 20 can help the desorption of gas by utilizing other heat (including heat used in the heater 12 ) generated in a vessel such as a boiler other than the engine 100 .

However, the engine 100 may be operated with oil instead of gas, as will be described later. That is, when it is detected that the desorption and discharge of gas from the gas storage tank 10 is not smooth, oil is supplied to the engine 100 so that the engine 100 can be operated by the oil.

Thereafter, when the heat generated in the engine 100 is transferred to the gas storage tank 10 to implement desorption and discharge of gas, the engine 100 may switch operation to gas. Therefore, if the flow rate of the gas flowing along the gas supply line 13 is less than the reference value (or if the pressure in the gas storage tank 10 is greater than or equal to the reference value or the temperature is less than the reference value), the desorption of the gas is not sufficient and the engine 100 ) can convert operation to oil.

The oil storage tank 30 stores oil. The engine 100 may be a heterogeneous fuel engine 100 that consumes gas or oil, and in this embodiment, an oil storage tank 30 may be provided in case the engine 100 does not consume gas.

An oil supply line 31 may be connected from the oil storage tank 30 to the engine 100 , and an oil pump (not shown) may be provided in the oil supply line 31 to transfer oil. As mentioned above, the oil pump may be operated when the engine 100 is to be operated with oil to deliver oil to the engine 100 .

As described above, in this embodiment, compared to a general tank that stores gas in a liquid phase, the storage efficiency can be increased by storing the gas using an adsorbent, and the desorption and discharge of the gas using the heat of the engine 100 is implemented so that the gas is smoothly discharged. consumption can be guaranteed.

2 is a conceptual diagram of a gas processing system according to a second embodiment of the present invention.

Referring to FIG. 2 , the gas processing system 1 according to the second embodiment of the present invention includes a liquefied gas storage tank 40 and an surplus gas storage tank 50 .

The liquefied gas storage tank 40 stores liquefied gas. The liquefied gas may store the liquefied gas to be supplied to the consumer 100 , and the demand 100 may be the engine 100 or the like described in the first embodiment.

The liquefied gas storage tank 40 should store the liquefied gas in a liquid state. At this time, the liquefied gas storage tank 40 may store the liquefied gas at a pressure of 1 bar to 10 bar (eg 1.03 bar).

The liquefied gas storage tank 40 may be a stand-alone type, a membrane type, or the like, and may use various heat insulating structures so that the liquefied gas is stored in a liquid state. However, in the liquefied gas storage tank 40, boil-off gas from which the liquefied gas is naturally evaporated is continuously generated. At this time, the boil-off gas generated in the liquefied gas storage tank 40 may be treated by a compressor 41 or the like, which will be described later.

A boil-off gas supply line 43 may be connected from the liquefied gas storage tank 40 to the consumer 100 , and a compressor 41 may be provided in the boil-off gas supply line 43 . The compressor 41 is the same/similar to the compressor 11 in the first embodiment above.

In this embodiment, the compressor 41 may compress the boil-off gas discharged from the liquefied gas storage tank 40, and may be provided in plurality and may have, for example, five stages. In this case, the customer 100 may be connected to the downstream of the 5-stage compressor 41 or the downstream of the 2-stage compressor 41 according to the required pressure.

Compression heat is generated while the BOG is compressed by the compressor 41 to increase the volume of BOG, which leads to an increase in the load on the compressor 41 . Therefore, in this embodiment, the cooler 42 may be placed downstream of each compressor 41 to prevent this.

The cooler 42 may cool the boil-off gas heated by compression heat. Since the cooler 42 may be provided downstream of each compressor 41 , when the multi-stage compressors 41 are provided in series, the cooler 42 may be provided between the two compressors 41 .

However, it is expressed that the cooler 42 is located downstream of the most downstream compressor 41 in the drawing. In this case, the cooler 42 may be replaced with a heater 12 . This is to prepare for the case where the multi-stage compressed boil-off gas is lower than the required temperature of the consumer 100 . Alternatively, if the multi-stage compressed BOG is suitable for the required temperature of the customer 100 , the most downstream cooler 42 may be omitted.

However, in preparation for a case in which the flow rate of BOG does not reach the desired flow rate at the consumer 100, the present invention provides a liquefied gas supply connected from the liquefied gas storage tank 40 to the consumer 100 or the BOG supply line 43. A line 45 may be further included.

The liquefied gas supply line 45 may be connected from the liquefied gas storage tank 40 to the consumer 100 or the boil-off gas supply line 43 , and a vaporizer 46 may be provided. The vaporizer 46 may vaporize the liquefied gas using various heat sources and deliver it to the consumer 100 .

In addition, a liquefied gas pump (not shown) may be provided in the liquefied gas supply line 45 , and the liquefied gas pump may be installed inside and/or outside the liquefied gas storage tank 40 . Two or more liquefied gas pumps may be provided and may be arranged in series and/or in parallel.

The boil-off gas supply line 43 is provided with a boil-off gas discharge line 431 . BOG is generated in the liquefied gas storage tank 40 and discharged along the BOG supply line 43. In order to protect the consumers 100, etc. when the amount of BOG is excessive, at least some of BOG may be discharged to the outside.

In this case, a BOG combustion device 432 for burning BOG is provided in the BOG discharge line 431 , and a BOG discharge valve 433 for controlling the discharge of BOG to prevent overpressure may also be provided.

The boil-off gas discharge valve 433 sets a reference value and opens when the internal pressure of the boil-off gas supply line 43 is greater than or equal to the reference value so that at least a portion of the boil-off gas escapes to the outside through the boil-off gas discharge line 431. have. Through this, the internal pressure of the boil-off gas supply line 43 may be maintained at an appropriate pressure.

The surplus gas storage tank 50 stores excess gas exceeding the consumption amount of the consumer 100 among the liquefied gas or boil-off gas discharged from the liquefied gas storage tank 40 . The surplus gas storage tank 50 stores the surplus gas among the boil-off gas when the boil-off gas discharged from the liquefied gas storage tank 40 is greater than the consumption amount of the consumer 100 .

On the other hand, when the surplus gas storage tank 50 stores the liquefied gas vaporized by the vaporizer 46 as surplus gas, it is determined that the boil-off gas is less than the consumption amount of the consumer 100 and the liquefied gas is discharged, This may be done when surplus gas is unexpectedly generated (due to factors such as a sharp drop in the load of the engine 100) in the process of being delivered to the consumer 100 .

The surplus gas storage tank 50 may adsorb and store the surplus gas using an adsorbent, like the gas storage tank 10 described in the first embodiment. That is, the surplus gas storage tank 50 may have a higher storage efficiency than the liquefied gas storage tank 40 .

A surplus gas storage line 51 may be provided in the surplus gas storage tank 50 . The surplus gas storage line 51 may be branched from the boil-off gas supply line 43 and connected to the surplus gas storage tank 50 .

The surplus gas storage line 51 may be branched from the boil-off gas supply line 43 downstream of the compressor 41 , and the branching point of the surplus gas storage line 51 is the storage of the surplus gas storage tank 50 . It may be variously determined according to the pressure and the compression pressure of the compressor 41 .

A surplus gas delivery line 53 is connected to the surplus gas storage tank 50 , and the surplus gas delivery line 53 is connected from the surplus gas storage tank 50 to the boil-off gas supply line 43 . The surplus gas storage line 51 is configured to introduce surplus gas into the surplus gas storage tank 50 , while the surplus gas delivery line 53 transfers surplus gas from the surplus gas storage tank 50 to the consumer 100 . It may be configured for discharging.

The surplus gas delivery line 53 may be joined to the boil-off gas supply line 43 upstream of any one of the compressors 41 . The point at which the surplus gas delivery line 53 is connected to the boil-off gas supply line 43 may be variously determined according to the storage pressure of the surplus gas storage tank 50 and the required pressure of the consumer 100 .

A surplus gas discharge line 55 may be provided in the surplus gas storage tank 50 . Like the gas storage tank 10 described in the first embodiment, the excess gas storage tank 50 adsorbs well when the temperature is low and the pressure is high, and on the contrary, when the temperature is high and the pressure is low, desorption occurs well.

Therefore, in this embodiment, when it is necessary to take out the surplus gas from the surplus gas storage tank 50 and deliver it to the consumer 100 , the surplus gas of the surplus gas storage tank 50 is discharged to the surplus gas discharge line 55 , and the surplus It is possible to lower the internal pressure of the gas storage tank (50).

The surplus gas discharge line 55 may discharge the surplus gas to the outside or deliver it to the surplus gas combustion device 56 connected to the surplus gas discharge line 55, and the discharge of the surplus gas is to the surplus gas discharge line 55. It can be adjusted by the surplus gas discharge valve 57 provided.

The surplus gas discharge valve 57 may lower the pressure of the surplus gas storage tank 50 by discharging the surplus gas of the surplus gas storage tank 50 to the outside so that surplus gas is desorbed from the adsorbent.

As such, in this embodiment, when excess gas is generated among the liquefied gas/evaporated gas supplied from the liquefied gas storage tank 40 to the consumer 100, it is stored in the surplus gas storage tank 50 in an adsorption method with high storage efficiency. By storing it, efficient system operation is possible and fuel wastage can be prevented.

3 is a conceptual diagram of a gas processing system according to a third embodiment of the present invention.

Referring to FIG. 3 , the gas treatment system 1 according to the third embodiment of the present invention may further include an inlet-side heat exchanger 52 and an exhaust-side heat exchanger 54 compared to the second embodiment. In the following, parts omitted from description are replaced with descriptions in other embodiments.

The inlet-side heat exchanger 52 may be provided in the surplus gas storage line 51 to exchange the boil-off gas discharged from the liquefied gas storage tank 40 with the surplus gas flowing into the surplus gas storage tank 50 .

As described above, when the surplus gas is stored by adsorption, the adsorption occurs better when the temperature of the surplus gas is low. Therefore, in this embodiment, cryogenic boil-off gas discharged from the liquefied gas storage tank 40 may be used in order to increase the storage efficiency of the surplus gas.

To this end, the boil-off gas supply line 43 may be provided with a boil-off gas bypass line 44 connected to the inlet-side heat exchanger 52 . The boil-off gas bypass line 44 may be branched from the boil-off gas supply line 43 and rejoin the boil-off gas supply line 43 after passing through the inlet heat exchanger 52 , in the inlet heat exchanger 52 . The heat-exchanged boil-off gas may be introduced into the compressor 41 in a state in which the temperature has risen. This causes the load of the compressor 41 to rise.

However, this embodiment can solve this problem through the discharge side heat exchanger 54 .

The discharge side heat exchanger 54 may be provided in the surplus gas delivery line 53 to exchange the boil-off gas discharged from the liquefied gas storage tank 40 with the surplus gas discharged from the surplus gas storage tank 50 .

Since the surplus gas storage line 51 is branched from the boil-off gas supply line 43 downstream of any one of the compressors 41, it is in a state of receiving compression heat. will heat up

However, the heated BOG can be cooled again while exchanging heat with the surplus gas in the discharge side heat exchanger 54 , and since the cooled BOG flows into the compressor 41 , an increase in the load on the compressor 41 can be prevented. .

To this end, the boil-off gas bypass line 44 may be branched from the boil-off gas supply line 43 and connected to the boil-off gas supply line 43 through the inlet-side heat exchanger 52 and the exhaust-side heat exchanger 54 . That is, on the boil-off gas bypass line 44 , the inlet-side heat exchanger 52 and the outlet-side heat exchanger 54 may be provided in series.

As such, in this embodiment, it is possible to increase the adsorption and storage efficiency of the surplus gas by using the cooling heat of the boil-off gas transferred from the liquefied gas storage tank 40 to the consumer 100 , and also in the surplus gas storage tank 50 . It is possible to reduce the load of the compressor 41 by cooling the boil-off gas using the discharged surplus gas.

4 is a conceptual diagram of a gas processing system according to a fourth embodiment of the present invention.

Referring to FIG. 4 , the gas treatment system 1 according to the fourth embodiment of the present invention includes a boil-off gas storage tank 70 and a boil-off gas heat exchanger 71 .

In this embodiment, a bunkering vessel and a gas propulsion vessel are connected to each other for bunkering, and bunkering in which liquefied gas is supplied from the bunkering tank 60 provided in the bunkering vessel to the liquefied gas storage tank 40 provided in the gas propulsion vessel. It should be noted that it can be used if made, and the gas treatment system 1 of the present embodiment can be installed in a bunkering vessel and/or a gas propulsion vessel.

The BOG storage tank 70 stores BOG generated from the liquefied gas storage tank 40 to which liquefied gas is supplied during bunkering. In the liquefied gas storage tank 40 during the bunkering process, a large amount of boil-off gas is generated due to natural vaporization.

In the conventional case, boil-off gas generated in the liquefied gas storage tank 40 is burned and processed for a gas combustion unit (GCU), etc., resulting in wastage of the boil-off gas. By storing it and using it later, eco-friendly and high-efficiency bunkering can be realized.

In this case, the boil-off gas storage tank 70 may adsorb and store the boil-off gas using an adsorbent. The storage using the adsorbent is the same as/similar to that described in the gas storage tank 10 and the like, so a detailed description will be omitted. As described above, when the temperature of the boil-off gas supplied to the boil-off gas storage tank 70 is low, the adsorbent can adsorb more.

In this embodiment, the boil-off gas recovery line 47 is connected from the liquefied gas storage tank 40 to the bunkering tank 60 for the recovery of the boil-off gas, and the boil-off gas recovery line 47 is connected to a bunkering vessel or a gas propulsion vessel. As the BOG supply line 43 is connected to the provided engine 100, at least a portion of BOG generated during bunkering is recovered to the bunkering tank 60 of the bunkering vessel or supplied to the engine 100 and used. have.

However, since the BOG generated during bunkering is so large, unlike this embodiment, if BOG needs to be treated only by recovery to the bunkering tank 60 or operation of the engine 100, all BOG generated during the bunkering process is removed. Indigestion may result in incineration of boil-off gas.

However, in this embodiment, in addition to supplying the BOG generated during bunkering to the bunkering tank 60 or the engine 100, the BOG is adsorbed and stored in the BOG storage tank 70 using an adsorbent. By suppressing incineration, it is possible not to cause environmental pollution, and it is possible to reduce costs by omitting the installation of a gas combustion device.

The boil-off gas delivery line 471 branching from the boil-off gas recovery line 47 is connected to the boil-off gas storage tank 70 , and the evaporation discharged from the liquefied gas storage tank 40 along the boil-off gas recovery line 47 . At least a portion of the gas may be adsorbed to the adsorbent.

A compressor 41 for compressing the boil-off gas discharged from the liquefied gas storage tank 40 may be provided in the boil-off gas recovery line 47 or the boil-off gas delivery line 471 , and the compressor 41 is a boil-off gas storage tank It is possible to adjust the pressure for compressing the boil-off gas according to the storage amount of (70).

In addition, in order to sufficiently adsorb and store BOG, it is desirable to increase the pressure of BOG and lower the temperature. It is possible to deliver the boil-off gas to (70). In this case, the BOG storage tank 70 can store a large amount of BOG compared to the Type C type compression storage tank. In addition, in this embodiment, the BOG storage amount can be increased by cooling the BOG by utilizing the BOG heat exchanger 71, which will be described later.

The boil-off gas heat exchanger 71 cools the boil-off gas transferred to the boil-off gas storage tank 70 using liquefied gas. In this case, the liquefied gas may be liquefied gas supplied from the bunkering tank 60 to the liquefied gas storage tank 40 during bunkering.

The boil-off gas heat exchanger 71 may be provided on the bunkering line 61 provided with the bunkering valve 611 and the like, and has a 2-stream form in which the boil-off gas delivery line 471 and the bunkering line 61 are connected. can have Accordingly, the BOG flowing to the BOG storage tank 70 through the BOG delivery line 471 can be cooled with the liquefied gas flowing into the liquefied gas storage tank 40 through the bunkering line 61 .

In this embodiment, the BOG is cooled with liquefied gas and delivered to the BOG storage tank 70, so that the BOG storage efficiency can be increased in the BOG storage tank 70 using an adsorbent.

However, a bypass line 62 may be provided in the bunkering line 61 in which the boil-off gas heat exchanger 71 is provided to bypass the boil-off gas heat exchanger 71 , and a bypass valve is provided in the bypass line 62 . 621 may be provided.

At this time, the bypass valve 621 is provided in the boil-off gas recovery line 47 or the boil-off gas delivery line 471, etc., and interlocks with the boil-off gas sensor 472 that measures the temperature of the boil-off gas, and is connected to the boil-off gas sensor 472. The opening degree can be adjusted according to the temperature of the boil-off gas measured by the

If the temperature of the boil-off gas discharged from the liquefied gas storage tank 40 by natural vaporization is not high (less than the preset value), the present embodiment does not heat exchange the liquefied gas with the boil-off gas by increasing the opening degree of the bypass valve 621. By not doing so, it is possible to prevent unnecessary heating of the liquefied gas supplied from the bunkering tank 60 to the liquefied gas storage tank 40 .

Conversely, if the temperature of the BOG that is naturally vaporized and delivered to the BOG storage tank 70 is too high (above the preset value) to affect the adsorption storage, this embodiment shows that all or most of the liquefied gas is a BOG heat exchanger. In (71), it can be used to cool the boil-off gas.

Of course, the adjustment of the opening degree of the bypass valve 621 may be performed in conjunction with the operation of the above-mentioned compressor 41 , and the adjustment of the opening degree of the bypass valve 621 and operation of the compressor 41 are performed to store boil-off gas. The amount or pressure of BOG currently stored in the tank 70 and the temperature of BOG discharged through the BOG recovery line 47 may be variously performed.

For example, if the temperature of the boil-off gas discharged from the liquefied gas storage tank 40 is high, in this embodiment, the operation of the compressor 41 is increased, but the opening degree of the bypass valve 621 is increased to increase the pressure instead of the temperature of the boil-off gas. can be increased to increase the adsorption capacity. In this case, since the temperature rise of the liquefied gas transferred to the liquefied gas storage tank 40 is suppressed, the evaporative BOG can be efficiently stored in the BOG storage tank 70 while the discharge of BOG is also suppressed.

That is, in this embodiment, when the liquefied gas exchanges heat with the boil-off gas in the boil-off gas heat exchanger 71, as the temperature rises, natural evaporation of the boil-off gas may be generated in the liquefied gas storage tank 40. , in consideration of the internal temperature or internal pressure of the liquefied gas storage tank 40 , the operation of the compressor 41 and/or the opening degree of the bypass valve 621 may be appropriately adjusted.

As described above, the present embodiment can adsorb and store BOG generated during bunkering, thereby solving the problem of incineration of excess BOG, thereby implementing eco-friendly and high-efficiency bunkering.

In addition to the embodiments described above, the present invention encompasses all embodiments generated by a combination of at least one embodiment and a known technology or a combination of at least two or more embodiments.

Although the present invention has been described in detail through specific examples, this is for the purpose of describing the present invention in detail, and the present invention is not limited thereto, and by those of ordinary skill in the art within the technical spirit of the present invention. It will be clear that the transformation or improvement is possible.

All simple modifications and variations of the present invention fall within the scope of the present invention, and the specific scope of protection of the present invention will be made clear by the appended claims.

1: gas treatment system 10: gas storage tank
11: Compressor 12: Heater
13: gas supply line 14: gas discharge line
15: gas combustion device 16: gas discharge valve
20: heat transfer unit 21: heat recovery unit
22: heat transfer line 30: oil storage tank
31: oil supply line 40: liquefied gas storage tank
41: compressor 42: cooler
43: boil-off gas supply line 431: boil-off gas discharge line
432: boil-off gas combustion device 433: boil-off gas discharge valve
44: boil-off gas bypass line 45: liquefied gas supply line
46: vaporizer 47: boil-off gas recovery line
471: boil-off gas delivery line 472: boil-off gas sensor
50: surplus gas storage tank 51: surplus gas storage line
52: inlet side heat exchanger 53: excess gas delivery line
54: discharge side heat exchanger 55: excess gas discharge line
56: surplus gas combustion device 57: surplus gas discharge valve
60: bunkering tank 61: bunkering line
611: bunkering valve 62: bypass line
621: bypass valve 70: boil-off gas storage tank
71: boil-off gas heat exchanger 100: demand, engine

Claims (8)

BOG storage tank for storing BOG generated from a liquefied gas storage tank to which liquefied gas is supplied during bunkering; and
and a boil-off gas heat exchanger for cooling the boil-off gas delivered to the boil-off gas storage tank using liquefied gas supplied during bunkering,
The boil-off gas storage tank,
Absorbs and stores the boil-off gas using an adsorbent,
a bunkering line connected from a bunkering tank to the liquefied gas storage tank for bunkering;
a BOG recovery line connected from the liquefied gas storage tank to the bunkering tank for recovery of BOG; and
The gas treatment system further comprising a boil-off gas delivery line branched from the boil-off gas recovery line and connected to the boil-off gas storage tank. The method of claim 1,
The boil-off gas heat exchanger, Gas processing system, characterized in that provided on the bunkering line. 3. The method of claim 2,
The gas treatment system further comprising a bypass line provided to bypass the boil-off gas heat exchanger in the bunkering line. delete 4. The method of claim 3,
a boil-off gas sensor provided in the boil-off gas recovery line or the boil-off gas delivery line to measure the temperature of the boil-off gas; and
Further comprising a bypass valve provided on the bypass line,
The bypass valve, gas processing system, characterized in that the opening degree is controlled according to the temperature of the boil-off gas measured by the boil-off gas sensor. 4. The method of claim 3,
The gas treatment system according to claim 1, further comprising a compressor provided in the boil-off gas recovery line or the boil-off gas delivery line to compress the boil-off gas discharged from the liquefied gas storage tank. The method of claim 6, wherein the compressor,
Gas processing system, characterized in that the pressure for compressing the boil-off gas is adjusted according to the amount of storage in the boil-off gas storage tank. A ship having the gas treatment system according to any one of claims 1 to 3 and 5 to 7.

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