KR102684489B1 - Sea Water Discharging System And Method For Regasification Ship - Google Patents

Abstract

A seawater discharge system and method for a regasification vessel are disclosed. The seawater discharge system of the regasification ship of the present invention includes a heater that regasifies the liquefied gas in the regasification ship and heats the discharged heat medium by heat exchange with seawater; A seawater line that supplies and discharges seawater to the heater; And a manifold provided on the deck of the ship and arranged to extend the seawater line; It includes supplying the seawater discharged from the heater through the manifold to a jetty where the regasification vessel is moored, exchanging heat with the heat medium in the heater, and cooling the seawater to the jetty's facilities or on land. It is characterized by cooling land-based facilities, including power plants, mixing it with discharged seawater, heating it, and then discharging it overboard.

Description

Sea Water Discharging System And Method For Regasification Ship}

The present invention relates to a seawater discharge system and method for a regasification ship, and more specifically, to regasify liquefied gas, heat the discharged heat medium by heat exchange with seawater, and regasify the seawater cooled by heat exchange with the heat medium. It relates to a seawater discharge system and method for a regasification ship that transfers it to a jetty where the ship is moored, cools various facilities such as jetties or land power plants, mixes it with discharged seawater, and discharges it overboard.

Consumption of liquefied gases such as LNG (Liquefied Natural Gas) and LPG (Liquefied Petroleum Gas) is rapidly increasing worldwide. Liquefied gas is transported in a gaseous state through gas pipes on land or at sea, or is stored in a liquefied state on a liquefied gas carrier and transported to a distant consumer. Liquefied gases such as LNG or LPG are obtained by cooling natural gas or petroleum gas to extremely low temperatures (approximately -163°C in the case of LNG), and their volume is significantly reduced compared to the gaseous state, making them very suitable for long-distance transportation by sea.

Ships using LNG are typically ships with self-propelled capabilities such as LPG carriers, LNG carriers, liquid hydrogen carriers, and LNG RVs (Regasification Vessels), as well as LNG FPSOs (Floating Production Storage Offloading) and LNG FSRUs. Examples include offshore structures such as (Floating, Storage, Regasification Unit) that do not have propulsion capabilities but are floating in the sea.

Among ships that use LNG, an LNG regasification ship refers to a ship or floating structure that has the function of storing LNG in a cryogenic liquid state, regasifying it, and supplying it to customers on land. LNG is stored while floating at sea. These include an LNG FSRU in the form of an offshore floating structure with the purpose of regasification, and an LNG RV in the form of a ship that has the function of an LNG carrier and has self-propulsion capability with the purpose of regasification.

These LNG regasification vessels can regasify LNG using seawater or air, which can be easily obtained at sea, as a heat source and supply it to gas consumers on land.

KR 10-1491032 B1

On LNG regasification ships, BOG that naturally occurs in an LNG storage tank can be compressed, or LNG can be pumped and compressed to high pressure, then regasified and transported overboard.

For this purpose, the ship is equipped with a recondenser that compresses the BOG generated in the LNG storage tank and mixes it with the LNG pumped from the LNG storage tank, an HP pump that receives the LNG condensed from the recondenser and compresses it to high pressure, and a recondenser that compresses the LNG compressed by the HP pump. It may include a vaporizer that receives LNG and vaporizes it, a metering unit that transports the gas vaporized in the vaporizer to the outside of the ship, a heat exchanger, and a manifold.

Regasifying low-temperature LNG requires a lot of heat energy. If the heat source is supplied from seawater, which is easily available on board a ship, a large amount of seawater is needed. Discharging the cooled seawater overboard as it is after using it as a heat source is not recommended for the surrounding marine ecosystem. may have a negative impact. Additionally, design limitations may arise due to the temperature of the seawater to be discharged overboard.

According to one aspect of the present invention for solving the above-described problem, a heater that regasifies liquefied gas in a regasification ship and heats the discharged heat medium by heat exchange with seawater;

A seawater line that supplies and discharges seawater to the heater; and

A manifold provided on the deck of the ship and arranged to extend the seawater line; Including,

Seawater discharged from the heater is supplied through the manifold to a jetty where the regasification vessel is moored, exchanges heat with the heat medium in the heater, and the cooled seawater is supplied to the jetty's facilities or to land, including an onshore power plant. A seawater discharge system for a regasification ship is provided, which is characterized in that the facility is cooled, mixed with discharged seawater, warmed, and then discharged overboard.

Preferably, the manifold is placed in the forward (FWD) or middle (MID) position on the deck, and a flexible hose is connected to the manifold to supply seawater discharged from the heater to the jetty. .

Preferably, a cooling water discharge pipe is provided at the jetty and transports seawater discharged after being supplied as cooling water to the jetty facilities or the land facilities, wherein the flexible hose is connected to the cooling water discharge pipe, and the flexible hose is connected to the cooling water discharge pipe. Seawater cooled in the heater may be mixed with seawater discharged after being supplied as the cooling water and discharged overboard.

Preferably, it is provided at the jetty and stores seawater to be discharged after being supplied as cooling water to the jetty's facilities or the land-based facilities, and the flexible hose is connected to the coolant discharge tank, wherein the flexible hose is connected to the coolant discharge tank. Seawater cooled in the heater may be mixed with seawater discharged after being supplied as the cooling water and discharged overboard in the cooling water discharge tank.

According to another aspect of the present invention, the liquefied gas is regasified in a regasification ship, the discharged heat medium is heated by heat exchange with seawater, and the seawater cooled by heat exchange with the heat medium is discharged overboard,

Seawater cooled by heat exchange is transferred through a manifold to the jetty where the regasification ship is moored, and the jetty's equipment or land-based facilities, including the land-based power plant, are cooled, mixed with discharged seawater, heated, and then discharged overboard. A method for discharging seawater from a regasification ship is provided.

Preferably, the manifold is placed in the forward (FWD) or middle (MID) on the deck of the ship, and a flexible hose is connected to the manifold to supply the cooled seawater to the jetty. .

In the present invention, liquefied gas is regasified in a regasification ship, the discharged heat medium is heated by heat exchange with seawater, and the seawater cooled by heat exchange with the heat medium is transferred to the jetty where the regasification ship is moored. Cool various facilities or land-based facilities, mix with discharged seawater, and discharge overboard.

Through this, when designing a heater, the temperature difference between the heating medium and seawater can be designed and operated to reduce the amount of seawater used. Furthermore, costs can be reduced by reducing the use of pumps for seawater intake, and the discharge of supercooled seawater It can reduce the impact on the marine ecosystem around ships.

1 and 2 schematically show an example of the arrangement of a manifold in the seawater discharge system of a regasification ship according to the first embodiment of the present invention, respectively.
Figure 3 schematically shows a seawater discharge system of a regasification vessel according to a first embodiment of the present invention.
Figure 4 schematically shows a seawater discharge system of a regasification vessel according to a second embodiment of the present invention.

In order to fully understand the operational advantages of the present invention and the objectives achieved by practicing the present invention, reference should be made to the accompanying drawings illustrating preferred embodiments of the present invention and the contents described in the accompanying drawings.

Hereinafter, the structure and operation of a preferred embodiment of the present invention will be described in detail with reference to the attached drawings. Here, in adding reference numerals to components in each drawing, it should be noted that identical components are indicated with the same reference numerals as much as possible, even if they are shown in different drawings.

Figures 1 and 2 schematically show an example of the arrangement of a manifold in the seawater discharge system of a regasification ship according to the first embodiment of the present invention, and Figure 3 shows a seawater discharge of a regasification ship according to the first embodiment of the present invention. The system is schematically shown.

The regasification vessel in this embodiment and the second embodiment described later is a ship or floating structure that has the function of storing LNG in a cryogenic liquid state, regasifying it, and supplying it to overboard, such as to demand places on land, and is a representative example. For example, FSRU and LNG RV are included.

As shown in Figures 1 to 3, the system of the first embodiment includes a heater 100 that regasifies the liquefied gas in the regasification vessel (S) and heats the discharged heat medium by heat exchange with seawater, and a heater that heats the seawater. A seawater line (SL) for supply and discharge, a heat medium circulation line (GL) through which heat medium cooled by heat exchange with liquefied gas is circulated to the heater, and a manifold (M) provided on the deck of the ship and arranged by extending the seawater line. It includes a seawater line and a flexible hose (FH) connected to the manifold, and the flexible hose is connected to a jetty (J) where the regasification vessel is moored.

In this embodiment, the cooled seawater is exchanged with the heat medium in the heater 100 and sent to the jetty (J) through the manifold (M) and the flexible hose (FH) to be used for various facilities in the jetty or on land, such as an onshore power plant. It is characterized by cooling the equipment, mixing it with heated seawater, warming it, and then discharging it overboard.

In the heat medium circulation line (GL), a heat medium for heating the liquefied gas, such as LNG, circulates through heat exchange with the liquefied gas in the vaporizer (not shown) of the regasification ship. For example, glycol water may be used as such a heat medium. In a regasification ship, the liquefied gas is compressed and then regasified through heat exchange with a heating medium in a vaporizer and can be transported overboard. The heat medium cooled by heat exchange with liquefied gas such as LNG in the vaporizer is supplied to the heater 100, and is heated by receiving heat energy from seawater in the heater and then circulated back to the vaporizer.

In this embodiment, the liquefied gas is configured to exchange heat with the heat medium, and the heat medium cooled through heat exchange is then configured to heat exchange with seawater. However, it can also be configured to directly exchange heat with the liquefied gas and seawater, and in this case, the liquefied gas By directly exchanging heat and sending the cooled seawater to the jetty, it cools onshore facilities such as jetty facilities and land power plants, and can be mixed with heated seawater and discharged overboard. For example, a land-based facility may be a power plant that receives vaporized gas from a regasification ship, generates electricity, and supplies power to power consumers.

Upstream of the seawater line (SL), valves (V1, V2, V3, V4) that open and close the seawater line and a flushing filter (200) that filters out foreign substances contained in seawater may be provided.

As shown in Figures 1 and 2, the manifold (M) may be placed in forward (FWD) or middle (MID) on the deck. The position of the manifold (M) can be adjusted depending on the jetty situation.

In this embodiment, the flexible hose is connected to the coolant discharge pipe (CL), which transports seawater that is supplied as coolant to the jetty equipment and then discharged overboard, exchanges heat with the heat medium in the heater, and transfers the cooled seawater to the jetty or land. It is supplied as cooling water to various devices and facilities, and while cooling these facilities, it can be mixed directly with seawater that is heated and discharged from the pipe and discharged overboard.

Figure 4 schematically shows a seawater discharge system of a regasification vessel according to a second embodiment of the present invention.

As shown in FIG. 4, in the system of the second embodiment, the coolant discharge tank (P), which stores seawater to be discharged overboard after being supplied as coolant to the jetty equipment in the system of the first embodiment, is connected to the coolant discharge pipe (CL). Additionally, a flexible hose connected from the regasification vessel (S) is connected to the cooling water discharge tank (P) of the jetty (J), and the seawater cooled from the heater of the regasification vessel is supplied to the seawater line, manifold, and flexible hose. It is supplied to the cooling water discharge tank through the jetty, and is supplied as cooling water for various facilities in various facilities or land facilities, and is then mixed with sea water to be discharged to the sea in the cooling water discharge tank and discharged overboard. By providing such a cooling water discharge tank, even if there is a difference in the amount or generation time of seawater cooled in the regasification ship and seawater heated in the jetty or land facilities, it can be collected and properly mixed and discharged in the tank, enabling flexible operation and overboard discharge. The temperature of the seawater can be arbitrarily adjusted.

As discussed above, in the present embodiments, the cooled seawater used in the regasification ship is sent to the jetty where the regasification ship is moored, and the various facilities, devices, or land facilities of the jetty are cooled and mixed with the heated seawater. By discharging overboard, design constraints are reduced when designing the heater, allowing a larger temperature difference between the heating medium and seawater to be designed, and reducing the amount of seawater used, reducing the capacity and use of pumps for seawater intake, thereby reducing device configuration and Operation costs can be reduced. Additionally, environmental pollution caused by overboard discharge of supercooled seawater and adverse effects on the marine ecosystem around the ship can be reduced.

It is obvious to those skilled in the art that the present invention is not limited to the above-mentioned embodiments, and that it can be implemented with various modifications or variations without departing from the technical gist of the present invention. It was done.

S: Regasification vessel
J: Jetty
M: Manifold
FG: Flexible hose
SL: Seawater line
GL: Heat medium circulation line
100: heater
200: Flushing filter
CL: Coolant discharge pipe
P: Coolant discharge tank

Claims (6)

A heater that regasifies liquefied gas in a regasification ship and heats the discharged heat medium by heat exchange with seawater;
A seawater line that supplies and discharges seawater to the heater; and
A manifold provided on the deck of the ship and arranged to extend the seawater line; Including,
Seawater discharged from the heater is supplied through the manifold to a jetty where the regasification vessel is moored, exchanges heat with the heat medium in the heater, and the cooled seawater is supplied to the jetty's facilities or to land, including an onshore power plant. The equipment is cooled, mixed with discharged seawater, heated, and then discharged overboard.
A seawater discharge system for a regasification ship, characterized in that the temperature difference between the heating medium and seawater can be designed to be large when designing the heater. According to clause 1,
The manifold is arranged in the forward (FWD) or middle (MID) on the deck, and a flexible hose is connected to the manifold to supply seawater discharged from the heater to the jetty. The seawater discharge system of a chemical vessel. According to clause 2,
It further includes a cooling water discharge pipe provided at the jetty and transporting seawater discharged overboard after being supplied as cooling water to the jetty's facilities or land facilities,
The flexible hose is connected to the coolant discharge pipe, and the seawater cooled by the heater is mixed with seawater discharged after being supplied to the coolant and discharged overboard. According to clause 3,
It further includes a cooling water discharge tank provided at the jetty and storing seawater to be discharged after being supplied as cooling water to the jetty equipment or the land equipment,
The flexible hose is connected to the coolant discharge tank, and the seawater cooled by the heater is mixed with seawater discharged after being supplied to the coolant and the coolant discharge tank and discharged overboard. . In a regasification ship, the liquefied gas is regasified and the discharged heat medium is heated by heat exchange with seawater in a heater, and the seawater cooled by heat exchange with the heat medium is discharged overboard,
The seawater cooled by heat exchange is transferred through a manifold to the jetty where the regasification vessel is moored, and the jetty's equipment or land-based facilities, including the land-based power plant, are cooled, mixed with discharged seawater, heated, and then discharged overboard. ,
A seawater discharge method for a regasification ship, characterized in that the temperature difference between the heating medium and seawater can be designed to be large when designing the heater. According to clause 5,
The manifold is arranged in the forward (FWD) or middle (MID) on the deck of the ship, and a flexible hose is connected to the manifold to supply the cooled seawater to the jetty. Method of discharging sea water from a fire vessel.

Images