KR20230055692A - Fuel Supply System And Method For Ship - Google Patents

Abstract

A ship fuel supply system and a method thereof are disclosed. The ship fuel supply system of the present invention comprises: multiple power generation engines provided on a ship and producing electric power; an ammonia storage tank provided on the ship and storing ammonia; a liquefied gas storage tank provided on the ship and storing liquefied gas; and an oil fuel tank provided on the ship and storing marine oil fuel. All or a part of the multiple power generation engines are provided as an ammonia dual fuel power generation engine that is selectively supplied with ammonia from the ammonia storage tank and the marine oil fuel. The power produced by the ammonia dual fuel power generation engine can be supplied to the ship's propulsion propeller.

Description

Ship's fuel supply system and method {Fuel Supply System And Method For Ship}

The present invention relates to a fuel supply system and method for a ship, and more particularly, to supply ammonia as a fuel for a ship's engine to satisfy the regulatory standards set by international agreements and increase the efficiency of the ship's engine operating system. It's about the supply system.

Efforts are being made to reduce greenhouse gas emissions worldwide as the global warming phenomenon intensifies, and as the Kyoto Protocol in 1997, which contained the obligations of developed countries to reduce greenhouse gases, expired in 2020, the conference was held in Paris, France in December 2015. According to the Paris Climate Change Accord, which was adopted in the 21st United Nations Framework Convention on Climate Change and entered into force in November 2016, the 195 Parties participating in the agreement are making various efforts to reduce greenhouse gases.

Along with this global trend, interest in renewable energy (or renewable energy) such as wind power, solar power, solar heat, bioenergy, tidal power, and geothermal heat has increased and various technologies have been developed as pollution-free energy that can replace fossil fuels and nuclear power. are losing

Liquefied gas, including liquefied natural gas, can remove or reduce air pollutants during the liquefaction process, so it can be seen as an eco-friendly fuel with less air pollutant emissions during combustion. Accordingly, in recent years, consumption of liquefied gas such as liquefied natural gas (LNG) has been rapidly increasing worldwide. Since liquefied gas obtained by liquefying gas at a low temperature has a very small volume compared to gas, it has the advantage of increasing storage and transfer efficiency.

Liquefied natural gas is a colorless and transparent liquid obtained by liquefying natural gas containing methane as a main component by cooling it to about -162 ° C, and has a volume of about 1/600 compared to natural gas. Therefore, when the natural gas is liquefied and transported, it can be transported very efficiently.

Liquefied petroleum gas has a difference in liquefaction temperature depending on its composition, but in the case of petroleum gas whose main component is propane, it is liquefied at a low temperature of about -42 ℃ at atmospheric pressure, up to about 45 ℃ at 18 bar, and liquid up to 20 ℃ at 7 bar. state can be stored.

On the other hand, conventional LPG carriers adopt a fuel supply system using heavy oil such as bunker C oil, which is relatively inexpensive as a propulsion fuel for ships. Due to stricter regulations, a separate heavy fuel oil fuel tank (LSHFO tank) with low sulfur content had to be installed, and the demand for an eco-friendly fuel supply system that meets international environmental regulatory standards has increased.

In recent years, the application of fuel supply systems that use LPG or LNG and boil-off gas generated from them as propulsion fuel in LPG or LNG carriers is increasing, and in accordance with the strengthening of international exhaust gas emission regulations, general ships in addition to LPG or LNG carriers are also using LNG. Ships using it as a propulsion fuel are increasing.

IMO (International Maritime Organization), a UN specialized organization established to internationally unify ship routes, traffic rules, port facilities, etc., also reduced greenhouse gas emissions by 50% in 2050 compared to 2008 and 100% in 2100. % reduction (GHG Zero Emission) is presented as a goal, and regulations in each country and region are expected to be strengthened accordingly.

Recently, LNG or LPG, which is widely adopted as a ship fuel, is evaluated as an eco-friendly fuel compared to other fossil fuels previously used as ship fuel, but carbon dioxide is still generated during combustion, and ships that use it as fuel emit carbon dioxide during operation. .

According to EEDI (Energy Efficiency Design Index), a compulsory carbon dioxide reduction regulation applied by IMO to new ships, in the initial EEDI announcement, CO2 emissions in 2015 were reduced by 10% based on the CO2 emissions from 2013 to 2015 EEDI Phase 1 was applied, and it was scheduled to apply Phase 3 in 2025 by strengthening and applying one step every 5 years. As international interest in climate change and greenhouse gas emissions grows, regulations on carbon dioxide emissions from ships are being rapidly strengthened. It may be difficult to achieve CO2 emission regulations with ships that use CO2 as fuel.

Accordingly, various studies on eco-friendly ship fuels capable of reducing carbon dioxide emissions have been conducted, and recently, technologies related to ship engines capable of using ammonia as a fuel along with fuels such as LNG or LPG have been developed.

Ammonia (NH ₃ ) is a substance in which three hydrogens are bonded to one nitrogen, and it is easy to liquefy because it can form a strong hydrogen bond between molecules, and has a boiling point of -33.34 ° C and a melting point of -77.73 ° C under normal pressure.

The present invention is intended to propose a method for increasing the efficiency of an engine operating system while responding to the gradual strengthening of regulatory standards set forth in international agreements by reducing greenhouse gas emissions from a ship equipped with an engine.

According to one aspect of the present invention for solving the above problems, a plurality of power generation engines provided on the ship and generating power;

An ammonia storage tank provided in the ship and storing ammonia;

A liquefied gas storage tank provided in the ship and storing liquefied gas; and

An oil fuel tank provided in the ship and storing oil fuel for the ship;

All or part of the power generation engine is provided as an ammonia dual fuel power generation engine selectively supplied with ammonia from the ammonia storage tank and the marine oil fuel as fuel,

The ship's fuel supply system is provided, characterized in that the power produced by the ammonia dual fuel power generation engine can be supplied to the propeller for propulsion of the ship.

Preferably, the rest of the power generation engines other than the ammonia dual fuel power generation engine are dual fuel engines supplied with the liquefied gas and oil fuel for ships, and the ammonia evaporation gas generated in the ammonia storage tank is supplied to the dual fuel engine It can be re-liquefied by the cold heat of the liquefied gas and recovered to the ammonia storage tank.

Preferably, an ammonia pump for transferring ammonia from the ammonia storage tank to the ammonia dual fuel power generation engine; and an ammonia heater for heating the ammonia transferred from the ammonia pump and supplying the ammonia to the ammonia dual fuel power generation engine.

Preferably, a propulsion engine provided in the vessel and connected to the propeller for propulsion by a shaft; a liquefied gas supply line connected to the propulsion engine from the liquefied gas storage tank to supply liquefied gas; And a shaft generator motor unit that is connected to a shaft connecting the propulsion engine and the propulsion propeller to generate electric power. Power may be provided to the propulsion engine.

Preferably, a variable frequency drive connected to the shaft generator motor unit; And a transformer connected to the variable frequency drive: the transformer is connected to the main switchboard of the ship, the surplus power of the power generation engine is supplied to the shaft generator motor unit and used in the propulsion engine, Electric power may be produced by the shaft generator motor unit with surplus output of the propulsion engine and supplied to the onboard power source.

Preferably, an exhaust discharge line provided with a selective catalytic reduction unit for discharging exhaust gas generated from the propulsion engine and the power generation engine overboard and denitrifying; a reducing agent heater which heats ammonia from the ammonia storage tank and supplies it to the selective catalytic reduction unit; a reducing agent valve controlling ammonia supplied from the reducing agent heater to the selective catalytic reduction unit; an exhaust analyzer provided in the exhaust discharge line to analyze the concentration of nitrogen oxides in the exhaust gas; and an unreacted ammonia analyzer provided in the exhaust discharge line to analyze the concentration of unreacted ammonia in the exhaust gas; Ammonia supplied to the selective catalytic reduction unit may be adjusted according to the reaction ammonia concentration.

Preferably, a buffer tank provided in the liquefied gas supply line and temporarily storing the liquefied gas transferred from the liquefied gas storage tank; a liquefied gas pump for receiving and compressing liquefied gas from the buffer tank; And a heater for heating the liquefied gas compressed by the liquefied gas pump: The liquefied gas may be LPG.

Preferably, a generator provided in the power generation engine to generate power; a propulsion motor connected to a rotating shaft of the propeller for driving the propeller for propulsion; a frequency converter connected to the propulsion motor; a switchboard for distributing electricity generated by the generator; and a transformer for converting the electricity distributed in the switchboard to be suitable for the propulsion motor and supplying the converted electricity to the frequency converter.

an exhaust discharge line provided with a selective catalytic reduction unit for discharging exhaust gas generated from the power generation engine outboard and denitrifying; a reducing agent heater which heats ammonia from the ammonia storage tank and supplies it to the selective catalytic reduction unit; a reducing agent valve controlling ammonia supplied from the reducing agent heater to the selective catalytic reduction unit; an exhaust analyzer provided in the exhaust discharge line to analyze the concentration of nitrogen oxides in the exhaust gas; and an unreacted ammonia analyzer provided in the exhaust discharge line to analyze the concentration of unreacted ammonia in the exhaust gas; Ammonia supplied to the selective catalytic reduction unit may be adjusted according to the reaction ammonia concentration.

a regasification gas supply line for vaporizing the liquefied gas in the liquefied gas storage tank and supplying it to land; a recondenser provided in the regasification gas supply line; a boil-off gas supply line for transporting boil-off gas generated in the liquefied gas storage tank to the recondenser; a compressor provided in the boil-off gas supply line to compress the boil-off gas to be transported to the recondenser; a compression pump provided downstream of the recondenser in the regasification gas supply line to compress liquefied gas; and a forced vaporizer provided in the regasification gas supply line to forcibly vaporize the liquefied gas compressed by the compression pump.

According to another aspect of the present invention, an ammonia storage tank for storing ammonia in a ship, a liquefied gas storage tank for storing low-temperature liquefied gas, and an oil fuel tank for storing oil fuel for ships are provided,

An ammonia dual fuel power generation engine that selectively receives ammonia from the ammonia storage tank and the marine oil fuel is provided as all or part of a plurality of power generation engines that generate power in the ship, and the ammonia dual fuel power generation engine is The remaining power generation engines are provided as dual fuel engines supplied with the liquefied gas and oil fuel for ships,

There is provided a fuel supply method for a ship, characterized in that the power produced by the ammonia dual fuel power generation engine can be supplied to the propeller for propulsion of the ship

In the present invention, all or part of the ship's power generation engine is provided as an ammonia dual fuel power generation engine that is selectively supplied with ammonia and marine oil fuel, and the power generated from the ammonia dual fuel power generation engine is supplied to the propeller for propulsion of the ship. make it possible Through this, by using ammonia, which is an eco-friendly fuel, as fuel for ship engines, it is possible to reduce greenhouse gas emissions and meet regulatory standards set by international agreements. In addition, by supplying ammonia as a fuel for a power generation engine instead of a propulsion engine in which the scale of fuel supply facilities such as a storage tank and a compressor increases for fuel supply because the fuel supply pressure is generally higher than that of a power generation engine and the fuel consumption is high, It can contribute to securing space on board by reducing the cost of engine adoption and reducing the size of additional facilities required for fuel supply.

In particular, it is possible to flexibly respond to the gradual strengthening of greenhouse gas emission standards by gradually increasing the proportion of ammonia dual-fuel power generation engines among power generation engines, thereby meeting the needs of ship owners and enhancing the sales competitiveness of ships.

Furthermore, in the present invention, a shaft generator motor unit is provided on the shaft of a propulsion engine in a ship to supply electric power produced by an ammonia dual fuel power generation engine to a propeller for propulsion, or to provide a generator for a propulsion motor and power generation engine that drives the propeller for propulsion. Thus, it is possible to operate a ship with electricity generated from eco-friendly fuel. In addition, power can be supplied to the propulsion engine with the surplus power of the power generation engine, and the surplus output of the propulsion engine can be supplied to the on-board power generation, thereby increasing the flexibility and efficiency of the operating system by operating the ship's propulsion engine and power generation engine integratedly during ship operation. can

1 schematically shows a fuel supply system for a ship according to a first embodiment of the present invention.
2 schematically shows a fuel supply system for a ship according to a second embodiment of the present invention.
3 schematically shows a fuel supply system for a ship according to a third embodiment of the present invention.
4 schematically shows a fuel supply system for a ship according to a fourth embodiment of the present invention.
5 schematically shows a fuel supply system for a ship according to a fifth embodiment of the present invention.

In order to fully understand 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 illustrating preferred embodiments of the present invention and the contents described in the accompanying drawings.

Hereinafter, the configuration and operation of a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings. In adding reference numerals to the components of each drawing, it should be noted that the same components are marked with the same numerals as much as possible, even if they are displayed on different drawings.

Hereinafter, the ship in the present invention may include a ship with self-propelled capability, as well as an offshore structure that does not have propulsion capability but floats on the sea, for example, an ammonia carrier, an LNG carrier, and a liquid hydrogen carrier. It may be a carrier, Arctic LNGC, LNG Regasification Vessel (RV), Floating Production Storage Offloading (FPSO), Floating Storage Regasification Unit (FSRU), and the like.

1 to 5 schematically show a fuel supply system for a ship according to first to fifth embodiments of the present invention, respectively.

1 to 5, the fuel supply system of the present embodiments includes an ammonia storage tank (NT) for storing liquid ammonia, a liquefied gas storage tank (LT) for storing liquefied gas such as LNG or LPG, and HFO , LSFO, MGO, MDO, ULSFO, etc. are provided with an oil fuel tank (OT) for storing marine oil fuel, and a fuel supply system for supplying fuel to an engine in a ship equipped with a plurality of power generation engines.

In particular, in the present embodiments, all or part of the power generation engine (GE, NGE) is provided as an ammonia dual fuel power generation engine (NGE) that is selectively supplied with ammonia and marine oil fuel from an ammonia storage tank. Ammonia (NH ₃ ) is a material in which three hydrogens are combined with one nitrogen, and when used as a fuel and completely burned, only nitrogen and water are produced, so it is attracting attention as an eco-friendly fuel that does not generate carbon dioxide. In the present embodiments, ammonia is selectively supplied as fuel to the ammonia dual-fuel power generation engine among the power generation engines. For example, the power generation engine selectively supplies ammonia and marine oil fuel such as HFO, LSFO, MGO, MDO, and ULSFO It may be a dual fuel engine that can be received. In this case, the ammonia dual fuel power generation engine can be supplied with ammonia and marine oil fuel selected according to the operating sea area of the ship, operating conditions, carbon dioxide emission control standards to be applied to the ship, and the like.

Among the power generation engines, the remaining power generation engines other than the ammonia dual fuel power generation engine are provided as dual fuel engines supplied with liquefied gas such as LNG or LPG stored in the liquefied gas storage tank and marine oil fuel stored in the oil fuel tank. Among the power generation engines, the composition ratio of the ammonia dual fuel power generation engine and the dual fuel engine can be changed. It can also be provided as a power generation engine to supply ammonia, an eco-friendly fuel.

Depending on the type of ship, a separate propulsion engine may be provided in addition to the power generation engine, and each embodiment schematically shows a more specific fuel supply system configuration according to various ships, engine types, and liquefied gas fuel types.

First, the system of the first embodiment of FIG. 1 schematically shows a fuel supply system for a ship equipped with a high-pressure two-stroke engine that stores LNG in a liquefied gas storage tank and receives LNG and oil fuel through a propulsion engine (ME). is depicted as

As shown in FIG. 1, a plurality of power generation engines (GE, NGE), which are four-stroke engines, are provided, and some of them are ammonia dual fuel power generation engines (NGE) supplied with LNG, oil fuel and ammonia as fuel. , the rest of the power generation engine (GE) is provided as a dual fuel engine supplied with existing LNG and oil fuel.

An ammonia storage tank (NT) for storing ammonia, a liquefied gas storage tank (LT) for storing LNG, and an oil fuel tank (OT) for storing oil fuel for ships are provided, respectively. A liquefied gas supply line (LL) is provided to supply LNG from the liquefied gas storage tank to the propulsion engine and power generation engine, the ammonia supply line (NL) is connected from the ammonia storage tank to the ammonia dual fuel power generation engine, and the oil fuel tank Oil supply lines OL1 and OL2 are respectively connected to the propulsion engine and the power generation engine. The boil-off gas generated from the LNG of the liquefied gas storage tank may be discharged to the outside of the tank through the boil-off gas supply line (GL) to be re-liquefied (300) or supplied as fuel for propulsion engines and power generation engines through a compressor (310).

In the propulsion engine (ME), for example, LNG of 25 to 45 ° C., 300 bar through a liquefied gas pump and a vaporizer through a liquefied gas supply line, or 5 to 20 bar, 25 to 20 bar from an oil fuel tank through an oil supply line. Oil fuel around 45℃ can be supplied as fuel.

In the ammonia dual fuel power generation engine (NGE), ammonia at around 5 to 80 bar and 25 to 45 ° C. passed through the ammonia pump and the ammonia heater 200 through the ammonia supply line (NL), 5 transferred from the oil fuel tank (OL1) Oil fuel at 20 bar, or LNG at 5 to 20 bar, 25 to 45 ° C. can be selectively supplied as fuel, and to a power generation engine (GE) other than an ammonia dual fuel power generation engine, 5 transferred from an oil fuel tank Oil fuel at 20 bar, or LNG at 5 to 20 bar and 25 to 45° C. may be supplied as fuel.

In this way, in this embodiment, greenhouse gas emissions can be reduced by using ammonia, which is an environmentally friendly fuel, as a fuel for a ship engine. In general, propulsion engines have a higher fuel supply pressure than power generation engines and consume more fuel, and the calorific value of ammonia is lower than that of LNG, LPG or diesel. There is a problem with scaling up. However, in the present embodiments, by first supplying ammonia as a fuel for a power generation engine instead of a propulsion engine, it is possible to reduce the cost of adopting an engine for eco-friendly fuel and reduce the size of additional facilities required for fuel supply, thereby contributing to securing space on board and efficient equipment arrangement. can Furthermore, while reducing greenhouse gas emissions, prioritized supply of existing proven fuel to the propulsion engine reduces the risk that may occur during operation and provides competitiveness for conservative ship owners. By replacing all of them with engines that can be supplied with ammonia fuel, it is possible to respond to stricter emission standards and more flexible operation is possible.

In this embodiment, the flexibility and efficiency of the operating system of the ship engine, such as the power generation engine and the propulsion engine, can be further supplied by supplying the power generated from the ammonia dual fuel power generation engine (NGE) to drive the propeller (P) for propulsion of the ship. and prepare a basis for a green energy propulsion system for ship propulsion power.

To this end, a shaft generator motor unit (SGM) is provided that is connected to a shaft (S) connecting the propulsion engine (ME) and the propeller (P) for propulsion of the ship to produce power. The shaft generator motor unit (SGM) may provide power to the propulsion engine by driving the electric motor using the surplus power of the power generation engine as driving power.

In the system of this embodiment, a variable frequency drive (VFD) connected to the shaft generator motor unit and a transformer (TR) connected to the variable frequency drive are provided, and the transformer is installed on the main switch board (SWBD) of the ship. Connected.

The shaft generator motor unit (SGM) is a kind of power take-off device that is mechanically connected to the shaft (S) of the propulsion engine (ME) and can generate electric power by extracting a part of the power supplied from the propulsion engine, and is generated by the propulsion engine. In the possible RPM range, it serves as a generator. The shaft generator motor unit of the present embodiments has a function of being driven by an electric motor when using surplus in-board power produced by a power generation engine as a driving power source. In addition, in the present embodiments, devices such as a shaft generator motor unit (SGM), a variable frequency drive (VFD), a transformer (TR), and a main switch board (SWBD) are configured to operate in both directions.

Through this, it is possible to produce power in the shaft generator motor unit (SGM) with the surplus output of the propulsion engine (ME) to provide additional power to the propulsion engine or to supply it as an onboard power source. is supplied to the shaft generator motor unit (SGM) through the main switch board (SWBD) and driven by an electric motor as a driving power source to provide additional power to assist the output of the propulsion engine (ME).

In this way, the flexibility and efficiency of the operating system can be increased by operating the ship's propulsion engine and power generation engine integratedly during ship operation, and by operating the SGM at the maximum efficiency point of the propulsion engine, fuel consumption is reduced while supplying power on board with surplus output. By doing so, it is possible to reduce greenhouse gas and carbon emissions during ship operation by reducing the frequency of use of power generation engines. In addition, while laying the groundwork for a green energy propulsion system for ship propulsion power, while eliminating or reducing operational disruptions due to unexpected risks due to the use of eco-friendly fuel, in case the EEDI emission standards are gradually strengthened, we respond flexibly accordingly. It can operate while reducing carbon dioxide emissions step by step.

Meanwhile, liquid ammonia in the ammonia storage tank NT may be stored at around -34°C, and evaporation gas is generated from the liquid ammonia being stored. In this embodiment, boil-off gas generated from ammonia being stored can be re-liquefied using cold heat of LNG. To this end, a heat exchanger 110 capable of exchanging heat with ammonia boil-off gas is provided between the pump and the vaporizer of the liquefied gas supply line to re-liquefy the ammonia boil-off gas with the cold heat of LNG to be supplied to the propulsion engine and power generation engine. It can be recovered to the ammonia storage tank (RL1). A separate ammonia re-liquefaction unit 250 may be additionally provided to discharge the ammonia boil-off gas from the storage tank, re-liquefy it, and return it to the tank (RL2).

Exhaust gas generated from the propulsion engine and the power generation engine is discharged overboard through an exhaust discharge line (EL), and a selective catalytic reduction unit 400 for denitrifying the exhaust gas is provided in the exhaust discharge line. When ammonia is supplied as engine fuel, nitrogen oxides in the exhaust gas may be included more than when LPG or oil is used as fuel, and nitrogen oxides are also substances regulated by the IMO.

In this embodiment, in order to remove this, the selective catalytic reduction unit 400 is provided in the exhaust discharge line (EL), and nitrogen oxide is reduced by a reduction reaction. In many cases, an aqueous solution of urea ((NH ₂ ) ₂ CO) is used as a reducing agent in the selective catalytic reduction unit. Urea reacts with nitrogen oxides and decomposes into ammonia and carbon dioxide, which has the disadvantage of generating carbon dioxide. When stored in this state, the service life is reduced over time and a constant temperature must be maintained, so there is a problem of installation space and installation cost.

In this embodiment, ammonia is directly used as a reducing agent in the selective catalytic reduction unit instead of urea, and a reducing agent supply line (AL) is provided to supply liquid ammonia from the ammonia storage tank to the selective catalytic reduction unit to denitrate exhaust gas to the selective catalytic reduction unit. Ammonia is supplied as a reducing agent for

The reducing agent supply line is provided with a reducing agent heater 410 for heating ammonia to be supplied to the selective catalytic reduction unit, and a reducing agent valve (AV) for opening and closing the reducing agent supply line downstream of the reducing agent heater. Ammonia injected into the SCR reactor of the selective catalytic reduction unit through the reducing agent heater reacts with NOx in the presence of a catalyst to change into N ₂ and H ₂ O, reducing the NOx content in the exhaust, and the reaction formula is as follows.

Meanwhile, an exhaust analyzer 420 for analyzing the concentration of nitrogen oxides in the exhaust gas and an unreacted ammonia analyzer 430 for analyzing the concentration of unreacted ammonia in the exhaust gas are provided in the exhaust discharge line.

Unreacted ammonia included in the exhaust gas may also be used as a reducing agent in the selective catalytic reduction unit 400 .

Accordingly, the valve AV of the reducing agent supply line AL is opened and closed according to the nitrogen oxide concentration and the unreacted ammonia concentration in the exhaust gas analyzed by the exhaust analyzer 420 and the unreacted ammonia analyzer 430 to remove the ammonia from the ammonia storage tank. Ammonia supplied to the selective catalytic reduction unit can be controlled.

A ship to which the system of this embodiment is applied may be provided with an air lubrication system (ALS) that reduces frictional resistance during movement of the hull by spraying air to the outer bottom surface of the hull. The air lubrication system injects air into the outer bottom surface of the hull to continuously form an air layer between the hull and the seawater, thereby reducing the frictional resistance between the seawater and the hull when the ship moves, thereby improving the fuel efficiency of the ship. The air lubrication system may be supplied with power generated from a power generation engine (NGE, GE).

By configuring the air lubrication system as described above, while improving fuel efficiency by reducing frictional resistance during ship operation, it is driven by a power generation engine using ammonia, an eco-friendly fuel, to further increase the effect of reducing greenhouse gas emissions during ship operation.

Next, looking at the system of the second embodiment of FIG. 2, in the system of the second embodiment, LNG is supplied as the main fuel of the propulsion engine as in the first embodiment described above, but LNG is supplied at a fuel supply pressure of about 15 to 20 bar. This is a system in case a low-pressure 2-stroke engine such as an ME-GA or X-DF engine is provided as a propulsion engine (ME). Since the fuel supply pressure of the propulsion engine is lower than that of the first embodiment described above, LNG and boil-off gas are propelled in devices such as the pump 100 and the compressor 310 of the liquefied gas supply line (LL) and the boil-off gas supply line (GL). In accordance with the fuel supply conditions of the engine, it is compressed to a lower pressure than in the first embodiment. Since other configurations are similar to those of the first embodiment described above, redundant descriptions are omitted.

Next, the system of the third embodiment of FIG. 3 will be described. A description overlapping with that of the first embodiment described above will be omitted.

The third embodiment system of FIG. 3 is a fuel supply system in an electric motor propulsion type ship such as Arctic LNGC, and a separate 2-stroke propulsion engine is not provided in the ship, and power is generated from a 4-stroke power generation engine (GE, NGE) It is to supply power to the electric motor that drives the propeller (P) for propulsion.

As shown in FIG. 3, all or part of the power generation engine is an ammonia dual fuel power generation engine (NGE) supplied with LNG, oil fuel and ammonia as fuel, and the rest (GE) is a dual fuel engine supplied with existing LNG and oil fuel. Provided with a fuel engine.

A generator (G) for power generation is provided in each power generation engine, and electricity generated from the generator is distributed through a switchboard (SB). The rotating shaft of the propeller P for propulsion is connected to the motor PM for propulsion. The electricity distributed from the switchboard (SB) is converted to suit the propulsion motor through the transformer (TR), supplied to the frequency converter (CV), and supplied to the propulsion motor (PM) through the frequency converter for propulsion. The drive of the motor drives the propeller P for propulsion.

In this way, by replacing/operating all or part of the power generation engine in an electric motor propulsion type ship with an ammonia dual fuel power generation engine, a green energy propulsion system for ship propulsion power is prepared and greenhouse gas and carbon emissions are reduced during ship operation. can

The system according to the fourth embodiment of FIG. 4 is a Floating Storage Regasification Unit (FSRU) that regasifies LNG at sea and supplies it to the land (SH).

As shown in FIG. 4, a facility for regasifying LNG is provided at the top of the hull for this purpose, and a regasification gas supply line (LL2) for vaporizing liquefied gas from the liquefied gas storage tank (LT) and supplying it to the land (SH) this is provided The regasification gas supply line LL2 is provided with a recondenser 500, a compression pump 510 for compressing liquefied gas, and a forced vaporizer 520 for forcibly vaporizing the compressed liquefied gas. A boil-off gas supply line (GL) for transferring boil-off gas generated in the liquefied gas storage tank (LT) to the recondenser is provided, and a compressor 350 for compressing boil-off gas to be transferred to the recondenser is provided in the boil-off gas supply line. , The boil-off gas compressed in the compressor is mixed with the liquefied gas in the recondenser and condensed, and then can be supplied to the land (SH) through the compression pump and the forced vaporizer through the regasification gas supply line.

Even in the system according to the fourth embodiment of FIG. 4, as in the third embodiment described above, a separate two-stroke propulsion engine is not provided, and electricity generated from a four-stroke power generation engine (GE, NGE) drives the propeller P for propulsion. You can supply power to the motor.

Similarly, all or some of the power generation engines are ammonia dual fuel power generation engines (NGE) supplied with LNG, oil fuel and ammonia as fuel, and the remaining power generation engines (GE) are provided with dual fuel engines supplied with existing LNG and oil fuel. do. The electricity generated from the generator (G) of the power generation engine (GE, NGE) is distributed through the switchboard (SB), and the electricity distributed in the switchboard is converted to suit the propulsion motor through the transformer (TR) and converted into a frequency converter (CV ), and supplied to the propulsion motor (PM) to drive the propulsion propeller (P) by driving the propulsion motor.

Next, looking at the system of the fifth embodiment of FIG. 5, the system of the fifth embodiment stores LPG in a liquefied gas storage tank and is a two-stroke LPG dual fuel propulsion engine that receives oil and LPG as fuel through a propulsion engine (ME). It is a fuel supply system in case of adopting.

A buffer tank (BT) for temporarily storing the liquefied gas transferred from the liquefied gas storage tank is provided in the liquefied gas supply line (LL) connected to the propulsion engine (ME) and the power generation engine (GE, NGE), and the liquefied gas is liquefied from the buffer tank. A liquefied gas pump 100 for receiving and compressing gas and a heater 120 for heating the liquefied gas compressed by the liquefied gas pump are provided.

The propulsion engine (ME) may be, for example, a high-pressure two-stroke engine supplied with LPG at around 5 to 80 bar, 25 to 45 ° C. or oil fuel at around 5 to 20 bar as fuel, and a liquefied gas storage tank (LT) In the LPG is stored at around -53 ℃, transferred to the buffer tank (BT) can be supplied to the propulsion engine via the liquefied gas pump 100 and heater (! 20).

The power generation engine is a low-pressure four-stroke engine, all or part of which is provided as an ammonia dual fuel power generation engine (NGE), and through an ammonia supply line (NL), 5 to 80 bar, 25 to 45 Ammonia around °C, oil fuel at 5 to 20 bar transferred from the oil fuel tank (OT), or LPG at 5 to 50 bar and 25 to 45 °C can be selectively supplied as fuel. Oil fuel at 5 to 20 bar transferred from an oil fuel tank or LPG at 5 to 50 bar and 25 to 45° C. may be supplied as fuel to the power generation engine (GE), other than the ammonia dual fuel power generation engine.

As in the above-described systems of the first and second embodiments, a shaft generator motor unit (SGM) is provided on the shaft (S) connecting the propulsion engine (ME) and the propeller (P) for propulsion of the ship, and the shaft generator motor In case the surplus power produced by the generator engine is used as a driving power source, it has the function of being driven by an electric motor, shaft generator motor unit (SGM), variable frequency drive (VFD), transformer (TR), main switch board (SWBD) ) and the like are configured to be operable in both directions.

The surplus output of the propulsion engine (ME) produces power in the shaft generator motor unit (SGM) to provide additional power to the propulsion engine or to supply it to the onboard power generation, or conversely, the surplus power of the generator engine (GE) is supplied to the main switch board ( SWBD) is supplied to the shaft generator motor unit (SGM) and can be operated to provide additional power to assist the output of the propulsion engine.

As such, it is possible to flexibly respond to the gradual strengthening of greenhouse gas emission standards while increasing the flexibility and efficiency of the operating system by operating the ship's propulsion engine and power generation engine in an integrated manner during ship operation, laying the foundation for a green energy propulsion system for ship propulsion power. make it possible

It is obvious to those skilled in the art that the present invention is not limited to the above embodiments and can be variously modified or modified without departing from the technical gist of the present invention. it did

ME: propulsion engine
GE: Power generation engine
NGE: Ammonia Dual Fuel Power Engine
NT: ammonia storage tank
LT: Liquefied gas storage tank
OT: oil fuel tank
P: Propeller for propulsion

Claims (11)

A plurality of power generation engines provided on the ship and generating electric power;
An ammonia storage tank provided in the ship and storing ammonia;
A liquefied gas storage tank provided in the ship and storing liquefied gas; and
An oil fuel tank provided in the ship and storing oil fuel for the ship;
All or part of the power generation engine is provided as an ammonia dual fuel power generation engine selectively supplied with ammonia from the ammonia storage tank and the marine oil fuel as fuel,
The ship's fuel supply system, characterized in that the power produced by the ammonia dual fuel power generation engine can be supplied to the propeller for propulsion of the ship. According to claim 1,
The rest of the power generation engines other than the ammonia dual fuel power generation engines are dual fuel engines supplied with the liquefied gas and oil fuel for ships,
Ammonia evaporation gas generated in the ammonia storage tank is re-liquefied by the cold heat of the liquefied gas supplied to the dual fuel engine and returned to the ammonia storage tank. According to claim 2,
an ammonia pump transferring ammonia from the ammonia storage tank to the ammonia dual fuel power generation engine; and
Ammonia heater for heating the ammonia transported from the ammonia pump and supplying it to the ammonia dual fuel power generation engine: Ship's fuel supply system further comprising. According to claim 3,
A propulsion engine provided in the vessel and connected to the propeller for propulsion by a shaft;
a liquefied gas supply line connected to the propulsion engine from the liquefied gas storage tank to supply liquefied gas; and
Further comprising: a shaft generator motor unit connected to a shaft connecting the propulsion engine and the propulsion propeller to generate electric power;
The shaft generator motor unit drives a motor using surplus power of the power generation engine as a driving power source to provide power to the propulsion engine. According to claim 4,
a variable frequency drive connected to the shaft generator motor unit; and
Further comprising: a transformer connected to the variable frequency drive;
The transformer is connected to the main switchboard of the ship, the surplus power of the power generation engine is supplied to the shaft generator motor unit and used in the propulsion engine, and the shaft generator motor unit generates power with the surplus output of the propulsion engine, Ship's fuel supply system, characterized in that it can be supplied by power generation. According to claim 5,
an exhaust discharge line provided with a selective catalytic reduction unit for discharging exhaust gas generated from the propulsion engine and the power generation engine outboard and denitrifying;
a reducing agent heater which heats ammonia from the ammonia storage tank and supplies it to the selective catalytic reduction unit;
a reducing agent valve controlling ammonia supplied from the reducing agent heater to the selective catalytic reduction unit;
an exhaust analyzer provided in the exhaust discharge line to analyze the concentration of nitrogen oxides in the exhaust gas; and
Further comprising: an unreacted ammonia analyzer provided in the exhaust discharge line to analyze the concentration of unreacted ammonia in the exhaust gas;
The reducing agent valve controls the ammonia supplied to the selective catalytic reduction unit according to the concentration of nitrogen oxides and the concentration of unreacted ammonia in the exhaust gas analyzed by the exhaust analyzer and the unreacted ammonia analyzer. According to claim 6,
a buffer tank provided in the liquefied gas supply line and temporarily storing the liquefied gas transported from the liquefied gas storage tank;
a liquefied gas pump for receiving and compressing liquefied gas from the buffer tank; and
A heater for heating the liquefied gas compressed in the liquefied gas pump further includes,
The fuel supply system of a ship, characterized in that the liquefied gas is LPG. According to claim 3,
A generator provided in the power generation engine to generate power;
a propulsion motor connected to a rotating shaft of the propeller for driving the propeller for propulsion;
a frequency converter connected to the propulsion motor;
a switchboard for distributing electricity generated by the generator; and
The ship's fuel supply system further comprising: a transformer that converts the electricity distributed in the switchboard to be suitable for the propulsion motor and supplies it to the frequency converter. According to claim 8,
an exhaust discharge line provided with a selective catalytic reduction unit for discharging exhaust gas generated from the power generation engine outboard and denitrifying;
a reducing agent heater which heats ammonia from the ammonia storage tank and supplies it to the selective catalytic reduction unit;
a reducing agent valve controlling ammonia supplied from the reducing agent heater to the selective catalytic reduction unit;
an exhaust analyzer provided in the exhaust discharge line to analyze the concentration of nitrogen oxides in the exhaust gas; and
Further comprising: an unreacted ammonia analyzer provided in the exhaust discharge line to analyze the concentration of unreacted ammonia in the exhaust gas;
The reducing agent valve controls the ammonia supplied to the selective catalytic reduction unit according to the concentration of nitrogen oxides and the concentration of unreacted ammonia in the exhaust gas analyzed by the exhaust analyzer and the unreacted ammonia analyzer. According to claim 8,
a regasification gas supply line for vaporizing the liquefied gas in the liquefied gas storage tank and supplying it to land;
a recondenser provided in the regasification gas supply line;
a boil-off gas supply line for transporting boil-off gas generated in the liquefied gas storage tank to the recondenser;
a compressor provided in the boil-off gas supply line to compress the boil-off gas to be transported to the recondenser;
a compression pump provided downstream of the recondenser in the regasification gas supply line to compress liquefied gas; and
Ship's fuel supply system further comprising: a forced vaporizer provided in the regasification gas supply line to forcibly vaporize the liquefied gas compressed by the compression pump. Provide an ammonia storage tank for storing ammonia in the ship, a liquefied gas storage tank for storing low-temperature liquefied gas, and an oil fuel tank for storing oil fuel for ships,
An ammonia dual fuel power generation engine that selectively receives ammonia from the ammonia storage tank and the marine oil fuel is provided as all or part of a plurality of power generation engines that generate power in the ship, and the ammonia dual fuel power generation engine is The remaining power generation engines are provided as dual fuel engines supplied with the liquefied gas and oil fuel for ships,
A method for supplying fuel to a ship, characterized in that the electric power produced by the ammonia dual fuel power generation engine can be supplied to a propeller for propulsion of the ship.

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