KR102019269B1 - Fuel Supply System And Method For Ship Engine - Google Patents

Abstract

A fuel supply system and method of a marine engine is disclosed. The fuel supply system of the marine engine of the present invention, the pressure-resistant tank for storing the liquefied natural gas; A first flow path for vaporizing the liquefied natural gas stored in the pressure resistant tank and supplying the gas to the marine engine; And a second flow path for supplying BOG (Boil Off Gas) generated from the liquefied natural gas stored in the pressure resistant tank to the marine engine, wherein the design pressure of the pressure resistant tank is designed to be higher than the operating pressure of the marine engine. When the pressure is higher than the operating pressure of the marine engine, characterized in that at least one of the liquefied natural gas and BOG is supplied to the marine engine.

Description

Fuel Supply System And Method For Ship Engine

The present invention relates to a fuel supply system and method for a marine engine, and more particularly, to a pressure resistant tank for storing liquefied natural gas, and a first flow path for supplying liquefied natural gas and BOG stored in the pressure resistant tank to a marine engine, respectively. Including 2 flow paths, the pressure of the design pressure tank is designed to be higher than the operating pressure of the marine engine, if the internal pressure of the pressure-resistant tank is higher than the operating pressure of the marine engine, at least one of liquefied natural gas and BOG to the marine engine without pumping or compression It relates to a fuel supply system and method of a marine engine that is supplied one.

Recently, the consumption of liquefied gas such as LNG (Liquefied Natural Gas) and LPG (Liquefied Petroleum Gas) is increasing worldwide.

In particular, liquefied natural gas (Liquefied Natural Gas, hereinafter referred to as "LNG") is an environmentally friendly fuel with low emissions of air pollutants during combustion is increasingly used in many fields. Liquefied natural gas is a colorless and transparent liquid obtained by liquefying natural gas containing methane as a main component at about -162 ℃, and has a volume of about 1/600 compared to natural gas. Therefore, when liquefied into LNG when transporting natural gas can be transported very efficiently.

International standards for vessels and regulatory standards in each country are also becoming increasingly demanding, and interest in the eco-friendly, high-efficiency fuels of ships is increasing. One of them is the use of natural or forced vaporized gaseous gas with LNG as fuel. Dual Fuel Diesel Electric (DFDE) engine, which is a heterogeneous fuel engine, can be developed and used.

Publication No. 10-2008-0057421 (published June 25, 2008)

Liquefied natural gas includes ethane, propane, etc. in addition to methane, and its composition varies depending on the production site. The methane number and temperature required by the propulsion system are required to supply the fuel to a propulsion system such as an engine by forcibly vaporizing the liquefied natural gas. Must be supplied in accordance with the conditions.

In order to control the methane value, the liquefied natural gas can be forcibly vaporized, and the temperature can be lowered to liquefy and remove heavy hydrocarbons having a higher liquefaction point than methane. After the methane is adjusted, it can be compressed with a compressor and fueled according to the temperature conditions of the propulsion system.

The present invention is to provide an improved system that can supply fuel by controlling the methane value of liquefied natural gas having a different composition depending on the production site, and retains the BOG generated from the tank without burning or re-liquefying during operation. The design pressure of the tank is set so as to provide a system that can supply liquefied natural gas or BOG to the operating pressure of the engine without a compressor using only the internal pressure of the tank.

According to an aspect of the invention, in the fuel supply system of the marine engine,

A pressure resistant tank for storing liquefied natural gas;

A first flow path for vaporizing the liquefied natural gas stored in the pressure resistant tank and supplying the liquefied natural gas to the marine engine; And

It includes a second flow path for supplying the BOG (Boil Off Gas) generated from the liquefied natural gas stored in the pressure resistant tank to the marine engine,

The design pressure of the pressure resistant tank is designed to be higher than the operating pressure of the marine engine. When the internal pressure of the pressure resistant tank is higher than the operating pressure of the marine engine, at least one of the liquefied natural gas and the BOG is supplied to the marine engine. A fuel supply system of a marine engine is provided.

Preferably, at least one of the liquefied natural gas and the BOG may be supplied to the marine engine at the operating pressure of the marine engine by the internal pressure of the pressure resistant tank without compression by the compressor.

Preferably, the first flow path may be provided with a forced vaporizer for vaporizing the liquefied natural gas supplied to the marine engine.

Preferably, the first flow path to which the liquefied natural gas vaporized from the forced vaporizer is supplied, and the second flow path to which the BOG is supplied is further connected to a third flow path connected to the ship engine, wherein the vaporized liquefaction Heavy Hydro Carbon (HHC) included in at least one of natural gas and BOG may be removed while passing through a separator to control the methane number of the liquefied natural gas or BOG and be supplied to the marine engine.

Preferably, the third flow path may be provided with a heater in which the liquefied natural gas or BOG vaporized through the separator is heated in accordance with the temperature conditions required by the marine engine.

Preferably, the second flow path may be provided with a safety valve for opening and closing the second flow path to lower the internal pressure of the pressure-resistant tank.

Preferably, the pressure resistant tank is a stand-alone IMO C type tank, the design pressure of the pressure resistant tank can be set to hold the BOG or flash gas generated in the pressure resistant tank during the voyage of the vessel.

Preferably, the marine engine may be a DF (Dual Fuel) engine.

According to another aspect of the invention, in the fuel supply method of the marine engine,

Liquefied natural gas is stored in the pressure-resistant container, and vaporized liquefied natural gas stored in the pressure-resistant container is supplied to the marine engine, or BOG (Boil Off Gas) generated from the liquefied natural gas stored in the pressure-resistant container is supplied to the marine engine. Supply,

Design pressure of the pressure vessel is designed to be higher than the operating pressure of the marine engine, if the internal pressure of the pressure vessel is higher than the operating pressure of the marine engine is supplied to the liquefied natural gas or BOG to the marine engine without compression A fuel supply method of a marine engine is provided.

The fuel supply system and method for a marine engine of the present invention can supply fuel by adjusting the methane value of liquefied natural gas having a different composition according to the production site, and the design pressure of the pressure resistant tank is designed to be higher than the operating pressure of the marine engine to liquefy. When the internal pressure of the pressure resistant tank is higher than the operating pressure of the marine engine by the flash gas generated from natural gas, fuel can be supplied to the marine engine by the internal pressure without pumping or compression, thereby reducing fuel consumption and reducing the consumption of pumps and compressors. Configuration and running costs can be reduced.

1 schematically shows a fuel supply system of a marine engine according to a first embodiment of the present invention.
2 and 3 schematically show a fuel supply system of a marine engine according to a second embodiment of the present invention.
4 and 5 schematically show a dual fuel supply system of a marine engine according to a third embodiment of the present invention.

In order to fully understand the present invention, the operational advantages of the present invention, and the objects achieved by the practice of the present invention, reference should be made to the accompanying drawings which illustrate preferred embodiments of the present invention and the contents described in the accompanying drawings.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. Like reference numerals in the drawings denote like elements.

1 schematically shows a fuel supply system of a marine engine E according to a first embodiment of the present invention.

As shown in FIG. 1, the fuel supply system of the marine engine E according to the first embodiment may include a pressure resistant tank FT in which liquefied natural gas is stored and a liquefied natural gas stored in the pressure resistant tank FT. A pump 100 for boosting and a forced vaporizer 200 for receiving the liquefied natural gas from the pump 100 to vaporize and supply it to the marine engine E, the forced vaporizer 200 according to the composition of the liquefied natural gas By changing the heating temperature of the liquefied natural gas in the can be controlled the amount of HHC removal contained in the vaporized liquefied natural gas.

The marine engine E of the present embodiment may be a DF engine such as a dual fuel diesel generator (DFDG) or a dual fuel diesel electric engine (DFDE). DF engine is a fuel that mixes heavy oil and natural gas and uses it as fuel. It has less sulfur content than fuel oil only and has less sulfur oxides in the exhaust gas. Regulatory criteria can be met. The fuel supply system of DFDE and DFDG may include two fuel supply systems, a gas fuel system supplied with natural gas fuel and an oil fuel system supplied with diesel fuel. will be. The oil fuel system may be applied with known techniques for DFDE.

Natural gas is supplied to the DFDG or DFDE as fuel. In this embodiment, liquefied natural gas having a smaller volume than natural gas and having high space efficiency in transportation and storage is stored in a pressure-resistant tank (FT), and vaporized to these engines. Will be supplied.

In order to supply fuel to the engine, the forced vaporizer 200 heats the liquefied natural gas supplied from the pressure resistant tank FT by steam and heat exchange or heats the thermal medium with steam without directly exchanging the liquefied natural gas with steam. The liquefied natural gas may be vaporized by indirect heating through the heated heat medium. In particular, in the case of DFDG, the amount of liquefied natural gas supplied to the fuel is small. Therefore, when heat-exchanging steam and liquefied natural gas directly, excessive heat energy is supplied, which makes it difficult to control the process after heating. It may be desirable to vaporize the liquefied natural gas using a thermal medium such as).

This embodiment is to remove the liquid HHC (Heavy Hydro Carbon) in the liquid state contained in the liquefied natural gas vaporized in the forced vaporizer 200 to adjust the liquefied natural gas to the methane number (methane number) required by the marine engine (E) The separator 300 and the liquefied natural gas passing through the separator 300 may further include a heater 400 that is further heated in accordance with the temperature conditions required by the marine engine E. The HHC separated from the separator 300 may be returned to the pressure resistant tank FT. To this end, a return flow path RL connected to the pressure resistant tank FT from the separator 300 may be provided.

In addition to methane, natural gas contains hydrocarbon components having a plurality of hydrocarbons such as ethane, propane, butane and pentane and inert gas components such as nitrogen and carbon dioxide, and the composition ratio varies depending on the production site. Methane number refers to the composition ratio of methane in natural gas. When fuel is supplied that does not meet the methane value required by the engine, the engine knocks or explodes and burns before the top dead center. Abnormal combustion may occur. This abnormal combustion phenomenon may cause wear of the engine piston, and may cause problems such as deterioration of engine efficiency and device failure. This embodiment can increase the methane value of the fuel to be supplied to the engine to the extent that the engine needs to prevent such abnormal combustion phenomenon. The DF engine, which is the marine engine E of the present embodiment, generally requires 80 or more methane number, and the methane value of liquefied natural gas may be in the range of about 70 depending on the production site.

Ethane, propane, butane and the like contained in the forced vaporized liquefied natural gas have a higher liquefaction point than methane. Therefore, in the separator 300, while methane is in a gas state, heavy hydrocarbons (HHC) such as propane and butane are liquefied at a temperature that can be liquefied to remove the methane value of liquefied natural gas to the level required by the engine. Raised.

In particular, since the various hydrocarbons included in the liquefied natural gas have different liquefaction points, the separator is controlled by controlling the heating temperature of the liquefied natural gas in the forced vaporizer 200 in consideration of the composition of the liquefied natural gas and the methane value required by the engine. The amount of heavy hydrocarbon removal at 300 can be controlled. The vaporization temperature of the liquefied natural gas heated in the forced vaporizer 200 is -80 to -120 ℃, it is possible to adjust the vaporization temperature within the above range in consideration of different compositions according to the production place of the liquefied natural gas.

In the separator 300, heavy hydrocarbon components in a mist state included in the vaporized liquefied natural gas may be separated and removed from the packing part (not shown) on the upper part of the separator 300. The separated heavy hydrocarbon droplets are returned to the pressure resistant tank FT through the return flow path RL.

The vaporized liquefied natural gas may be adjusted to 80 or more, preferably 90 or more, more preferably 95 or more while passing through the separator 300 at about 70 methane. As the methane value is adjusted, the lower heating value (LHV) is higher than before passing through the separator.

For example, in case of General LNG (C1: 89.6%, N2: 0.6%), the methane value before separation is 71.3, and the LHV (lower heating value) is 48,872.8 kJ / kg (1 atm, saturated vapor). When vaporized by heating at −120 ° C. and separating gas / liquid through the separator 300, the methane number is 95.5 and the LHV is changed to 49,265.6 kJ / kg.

The vaporized liquefied natural gas may be further heated in the heater 400 after passing through the separator 300 and supplied to the DF engine at a temperature of −30 to 80 ° C., preferably 0 to 60 ° C.

The design pressure of the pressure resistant tank FT is designed to be higher than the operating pressure of the marine engine E. When the internal pressure of the pressure resistant tank FT is higher than the operating pressure of the marine engine E, the internal pressure is not pumped by the pump 100. The liquefied natural gas can be supplied to the marine engine E by the pressure.

The pressure resistant tank FT of the present embodiment is a stand-alone IMO C type tank, and design pressure of the pressure resistant tank FT to hold BOG or flash gas generated in the pressure resistant tank FT during the ship's voyage. Can be set.

By holding BOG or flash gas in a pressure resistant tank (FT) set at a design pressure capable of holding BOG or flash gas generated from liquefied natural gas during the ship's voyage, combustion of the BOG to prevent tank cracking due to increased pressure resistance It can prevent fuel waste such as making or discharging. In addition, when the internal pressure of the pressure resistant tank FT is gradually increased to reach a pressure higher than the operating pressure of the marine engine E, the liquefied natural gas may be directly supplied to the forced vaporizer 200 without pumping by the pump 100. After passing through the separator 300, it may be heated and supplied to the engine. In this case, since the pressure is higher than the operating pressure of the engine by the BOG or flash gas, it is not necessary to configure a separate compressor or the like in the present embodiment, which will be described in detail in the following examples.

2 and 3 schematically show a fuel supply system of a marine engine E according to a second embodiment of the present invention.

As shown in FIG. 2, the fuel supply system of the marine engine E according to the second embodiment of the present invention includes a pressure resistant tank FT storing liquefied natural gas and a liquefied natural stored in the pressure resistant tank FT. The first flow path (L1) for vaporizing the gas supplied to the marine engine (E) and the BOG (Boil Off Gas) generated from the liquefied natural gas stored in the pressure resistant tank (FT) for supplying the marine engine (E) Including the two flow paths (L2), the design pressure of the pressure-resistant tank (FT) is designed to be higher than the operating pressure of the marine engine (E), the internal pressure of the pressure-resistant tank (FT) is higher than the operating pressure of the marine engine (E) At least one of liquefied natural gas and BOG is supplied to the ground marine engine E.

The liquefied natural gas or BOG may be supplied to the marine engine E at the operating pressure of the marine engine E without compression by the compressor by the internal pressure of the pressure resistant tank FT, and the marine engine may be supplied to the first flow path L1. A forced vaporizer 200a may be provided to vaporize the liquefied natural gas supplied to (E).

In this embodiment as in the first embodiment described above, the marine engine E may be a DF (Dual Fuel) engine. The operating pressure of the DF engine varies depending on the licensor and the size, but is generally 2.5 to 9 bara, preferably Since it requires a natural gas supply of 5 to 7 bara, the pressure-resistant container is designed to accommodate BOG or flash gas generated from liquefied natural gas to a pressure higher than this operating pressure. Therefore, the design pressure of the pressure resistant tank (FT) is designed to a gauge pressure of 2 bar or more, preferably 3 bar to 30 bar, more preferably 7 to 15 bar, so that the operation required by a DF engine such as DFDE or DFDG is required. Fuel can be supplied at pressure.

When the internal pressure of the pressure resistant tank FT is increased by accommodating BOG or flash gas, the liquefied natural gas is supplied to the forced vaporizer 200a from the pressure resistant tank FT without pumping by the pump, and the vaporized liquefied natural gas is a compressor. The system is configured to meet the operating pressure of the DF engine without compression.

The systems of the first to third embodiments may further comprise a fuel supply system (not shown) of a high pressure gas propulsion engine using liquefied natural gas as fuel. That is, a high-pressure gas propulsion engine such as a ME-GI engine may be configured as a main propulsion engine of a ship, and the fuel supply system of the present embodiment may be added to the fuel supply system for the propulsion engine. The fuel supply system of a high-pressure gas propulsion engine, such as a ME-GI engine, includes a high-pressure pump for increasing the pressure of liquefied natural gas to a pressure of 150 to 400 bar and a vaporizer for vaporizing the compressed liquefied natural gas. At this time, some of the vapor and liquefied natural gas generated during operation of the high pressure pump may be returned to the pressure resistant tank (FT), and during the trip of the high pressure gas propulsion engine, all of the high pressure LNG supplied may be returned to the tank. In addition to the flash gas, there are a number of internal pressure increase factors. In addition, the droplets separated from the separator 300a to be described later may be returned to the pressure resistant tank FT through the third flow path L3 to increase the internal pressure. When the internal pressure of the pressure resistant tank FT is increased to the operating pressure of the DF engine by these factors, it is possible to supply fuel to the DF engine without configuring a pump or a compressor.

The first flow path L1 supplied with the liquefied natural gas vaporized from the forced vaporizer 200a and the second flow path L2 supplied with the BOG are joined to form a third flow path L3 and connected to the ship engine E. In the first flow path L1 or the third flow path L3, a methane value for removing liquefied natural gas from the marine engine E by removing HHC (Heavy Hydro Carbon) contained in at least one of vaporized liquefied natural gas and BOG. Separator 300a to adjust the (methane number) may be provided.

The separator may be provided in the first flow path L1 as shown in FIG. 2 (300a), or may be provided in the third flow path L3 where the first and second flow paths join as shown in FIG. 2 (300a '). ). The separator can be provided in the first flow path L1 as shown in FIG. 2 because the BOG is mainly made of methane, so that the separator can be supplied to the marine engine E without adjusting the methane number.

The droplets of the HHC separated from the separator 300a are returned to the pressure resistant tank FT through the return flow path RL. When the internal pressure of the pressure resistant tank FT is high and cannot be returned only by the pressure of the separated droplets, Collect enemies and return when the internal pressure of the pressure resistant tank (FT) drops.

The third flow path L3 may further include a heater 400a through which the vaporized liquefied natural gas or BOG that has passed through the separator 300a is heated in accordance with a temperature condition required by the marine engine E, and a second The oil passage L2 may be provided with a safety valve 500a for opening and closing the second oil passage L2 to lower the internal pressure of the pressure resistant tank FT.

In this embodiment, the pressure resistant tank FT is a stand-alone IMO C type tank, and the design pressure of the pressure resistant tank FT may be set to hold the flash gas generated in the pressure resistant tank FT during the ship's voyage. .

Descriptions overlapping with those described in the first embodiment will be omitted.

4 and 5 schematically show a dual fuel supply system of a marine engine E according to a third embodiment of the present invention.

4 and 5, the dual fuel supply system of the marine engine E according to the second embodiment is a pressure resistant tank FT storing liquefied natural gas in the fuel supply system of the marine engine E. And a first flow path L1 which vaporizes the liquefied natural gas stored in the pressure resistant tank FT and supplies it to the marine engine E, and BOG generated from the liquefied natural gas stored in the pressure resistant tank FT. Including a second flow path (L2) for supplying (Boil Off Gas) to the marine engine (E), the pressure resistant tank (FT) design pressure is designed to be higher than the operating pressure of the marine engine (E), pressure-resistant tank (FT) If the internal pressure of) is higher than the operating pressure of the marine engine E, at least one of the liquefied natural gas and the BOG may be supplied to the marine engine E by the internal pressure without pumping.

The first flow path (L1) is provided with a forced vaporizer (200b. 200c) for vaporizing the liquefied natural gas supplied to the ship engine (E), the present embodiment is pumped to supply the liquefied natural gas to the first flow path (L1) It may further include a fuel pump (100b, 100c).

The fuel pump 100 may be a pump in a liquid provided inside the pressure resistant tank FT, or may be provided outside the pressure resistant tank FT.

The marine engine E of the present embodiment may also be a DF engine such as a dual fuel diesel generator (DFDG) or a dual fuel diesel electric engine (DFDE). DFDG and DFDE are replaced with the contents described in the first embodiment.

When the internal pressure of the tank is low, the liquefied natural gas stored in the pressure resistant tank FT is boosted by pumping by the fuel pumps 100b and 100c and introduced into the forced vaporizers 200b and 200c. If the operating pressure is higher than the fuel pumps 100b and 100c, the pressure may be supplied to the forced vaporizer 200 only by the internal pressure of the tank itself. The liquefied natural gas boosted by pumping by the fuel pumps 100b and 100c or boosted by the internal pressure of the pressure resistant tank may be supplied to the engine by satisfying the operating pressure of the marine engine E without additional compression.

In the forced vaporizers 200b and 200c provided in the first flow path L1, the liquefied natural gas supplied from the pressure resistant tank FT is heated by heat and heat exchange with steam, or the heat medium is steamed without directly exchanging the liquefied natural gas with steam. After heating to liquefied natural gas may be vaporized by indirect heating through the heated thermal medium.

The first flow path L1 through which the liquefied natural gas vaporized from the forced vaporizers 200b and 200c is supplied and the second flow path L2 through which the BOG is supplied are joined and connected to the ship engine E (L3). Heavy Hydro Carbon (HHC) contained in at least one of the liquefied natural gas and the BOG is passed through the separators 300b and 300c and is removed to control the methane number of the liquefied natural gas or BOG to the marine engine E. Can be supplied.

Since the BOG does not need to go through the forced vaporizers 200b and 200c, if the internal pressure of the tank itself is greater than the operating pressure of the engine, the BOG may be introduced into the separator through the second flow path L2 without passing through the forced vaporizers 200b and 200c. .

However, in the present embodiment as in the above-described embodiment, the separator 300c may be provided at the confluence of the first and second flow paths as shown in FIG. 5 to introduce BOG into the separator 300c, but the pressure resistant tank FT may be used. Since the BOG generated in the methane is mostly made of methane, it is not necessary to control the methane number, so the separator 300b is provided in the first flow path L1 for vaporizing and supplying liquefied natural gas, as shown in FIG. The second flow path L2 may be configured to be joined to the rear end.

As described in the first embodiment, natural gas includes hydrocarbon components having a plurality of hydrocarbons such as ethane, propane, butane, and inert gas components such as nitrogen and carbon dioxide, in addition to methane, and the composition ratio varies depending on the production site. . In order to prevent abnormal combustion such as knocking in the engine or explosion of the piston before top dead center, which may occur when fuel that does not meet the methane value required by the engine is supplied, the present embodiment may be prevented. This can increase the methane value of the fuel to be supplied to the engine.

Since ethane, propane, butane, and the like contained in the forced vaporized liquefied natural gas have a higher liquefaction point than methane, in the separators 300b and 300c, methane is liquefied while heavy hydrocarbons (HHC) such as propane and butane are liquefied. By removing the liquefied heavy hydrocarbons to the desired temperature, the methane value of liquefied natural gas is raised to the level required by the engine.

Meanwhile, the heavy hydrocarbon component in the liquid state separated from the separators 300b and 300c may be restored to the pressure resistant tank FT through the return flow path RL.

At least one of vaporized liquefied natural gas and BOG passing through the separators 300b and 300c is heated in accordance with a temperature condition required by the marine engine E in the flow path L3 where the first and second flow paths join. The heater 400 may be further provided.

The pressure resistant tank FT is a stand-alone IMO C type tank, and the design pressure of the pressure resistant tank FT may be set to hold BOG or flash gas generated in the pressure resistant tank FT during the voyage of the ship.

By holding BOG or flash gas in the pressure resistant tank FT set to a design pressure capable of retaining BOG or flash gas generated from liquefied natural gas during the voyage of the ship, the internal pressure of the pressure resistant tank FT is gradually increased. When the pressure reaches a higher pressure than the operating pressure of the engine E, the liquefied natural gas can be supplied directly to the forced vaporizers 200b and 100c without being pumped by the fuel pumps 100b and 100c and passed through the separators 300b and 300c. After heating, it can be supplied to the engine. When the internal pressure of the pressure resistant tank FT is lower than the operating pressure of the marine engine E, the pressure is increased to the operating pressure of the marine engine E by pumping by the fuel pump, thereby forcing the vaporizers 200b and 200c and the separators 300b and 300c. Is supplied to the engine without further compression.

In this embodiment as in the first embodiment described above, the marine engine E may be a DF (Dual Fuel) engine. The operating pressure of the DF engine, such as DFDG or DFDE, varies depending on the licensor and size, but is generally 2.5 to 2.5. Since a natural gas supply of 9 bara, preferably 5 to 7 bara, is required, the pressure resistant container is designed to accommodate BOG or flash gas generated from liquefied natural gas up to a pressure higher than this operating pressure. Therefore, the design pressure of the pressure resistant tank (FT) is designed to a gauge pressure of 2 bar or more, preferably 3 bar to 30 bar, more preferably 7 to 15 bar, so that the operation required by a DF engine such as DFDE or DFDG is required. Fuel can be supplied at pressure.

As such, at least one of liquefied natural gas and BOG is supplied from the pressure resistant tank FT by the BOG or the flash gas to reach a pressure higher than the operating pressure of the engine. In this embodiment, a separate compressor or the like needs to be configured in the system. There will be no.

According to another aspect of the invention, in the fuel supply method of the marine engine,

The liquefied natural gas is stored in the pressure vessel, and the liquefied natural gas stored in the pressure vessel is vaporized and supplied to the marine engine, or the BOG (Boil Off Gas) generated from the liquefied natural gas stored in the pressure vessel is supplied to the marine engine.

The design pressure of the pressure vessel is designed to be higher than the operating pressure of the marine engine, and when the internal pressure of the pressure vessel is higher than the operating pressure of the marine engine, the marine engine, characterized in that to supply liquefied natural gas or BOG to the marine engine without compression. The fuel supply method of the is provided.

As described above, the fuel supply system of the marine engine E of the present exemplary embodiment may or may not pump liquefied natural gas from the pressure resistant tank FT through the first flow path L1 and the second flow path L2. The methane is increased by vaporizing the separator 300 and supplied to the ship engine E. At this time, the design pressure of the pressure resistant tank FT is designed to be higher than the operating pressure of the marine engine E, and the flash gas generated from the liquefied natural gas is held in the pressure resistant tank FT without the process of discharging or burning the gas. When the internal pressure of the pressure resistant tank FT is higher than the operating pressure of the marine engine E, liquefied natural gas or BOG can be supplied to the marine engine E by internal pressure without pumping or compressing.

According to this embodiment, fuel can be supplied by controlling the methane value of liquefied natural gas having a different composition according to the production site, and fuel can be supplied to the operating pressure of the marine engine E without a pump and a compressor only by the internal pressure of the pressure resistant tank FT. This prevents fuel waste due to BOG emissions or combustion and reduces the configuration and operating costs of pumps and compressors.

As described above, the present invention is not limited to the described embodiments, and various modifications and changes can be made without departing from the spirit and scope of the present invention, which will be apparent to those skilled in the art. Therefore, such modifications or variations will have to be belong to the claims of the present invention.

FT: pressure resistant tank
E: Marine Engine
L1: 1st flow path
L2: second euro
L3: Joining portion of the first flow path and the second flow path, the third flow path
RL: Return Euro
100, 100b, 100c: fuel pump
200, 200a, 200a ', 200b, 200c: forced vaporizer
300, 300a, 300a ', 300b, 300c: separator
400, 400a, 400a ', 400b, 400c: heater
500a, 500a ': safety valve

Claims (9)

delete delete delete delete delete delete delete delete In the fuel supply method of the marine engine,
Liquefied natural gas is stored in the pressure-resistant container, and vaporized liquefied natural gas stored in the pressure-resistant container is supplied to the marine engine, or BOG (Boil Off Gas) generated from the liquefied natural gas stored in the pressure-resistant container is supplied to the marine engine. Supply,
The liquefied natural gas controls the methane value by adjusting the vaporization temperature in the forced vaporizer to remove the heavy hydrocarbon components in the droplet state contained in the vaporized liquefied natural gas, and supplies to the marine engine,
Design pressure of the pressure vessel is designed to be higher than the operating pressure of the marine engine, the internal pressure due to the pressure increase factor including vapor generated during pump operation, liquefied natural gas and droplets, flash gas returned to the pressure vessel And when the internal pressure of the vessel is higher than the operating pressure of the marine engine, the liquefied natural gas or the BOG is supplied to the marine engine without compression.

Images