KR20240012649A - Ammonia Treatment System For Ship Engine - Google Patents

Abstract

An ammonia exhaust system for a marine engine is disclosed. The ammonia discharge system for a marine engine of the present invention includes a fuel supply unit that supplies ammonia to the engine in accordance with the fuel supply conditions of the engine in a ship equipped with an engine supplied with ammonia as fuel; An ammonia water tank filled with water to maintain a certain liquid level or higher and accommodating ammonia vented from the fuel pipe and fuel supply unit of the engine; A chiller that regulates the temperature of the ammonia water tank by circulating cooling water; A cooling water circulation line connected from the chiller to the chiller via the ammonia water tank; A coolant valve provided in the coolant circulation line; and a gas discharge line for discharging ammonia from the ammonia water tank overboard. When the ammonia discharged from the fuel pipe and the fuel supply unit flows into the ammonia water tank, the ammonia water tank is cooled through the chiller and the ammonia water tank is discharged from the ammonia water tank. It is characterized by controlling the amount of ammonia discharged through the gas discharge line.

Description

Ammonia Treatment System For Ship Engine}

The present invention relates to an ammonia treatment system for a marine engine, and more specifically, to an ammonia treatment system for a marine engine that can recover ammonia discharged from the fuel piping and fuel supply section of the engine and dilute and discharge it in accordance with the overboard emission standards. will be.

As the global warming phenomenon intensifies, efforts are being made to reduce greenhouse gas emissions around the world, and as the 1997 Kyoto Protocol, which included obligations for developed countries to reduce greenhouse gases, expires in 2020, the event held in Paris, France in December 2015 The 195 parties participating in the Paris Climate Change Accord, which was adopted at the 21st United Nations Framework Convention on Climate Change and came into effect in November 2016, are making various efforts with the goal of reducing 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 as a pollution-free energy that can replace fossil fuels and nuclear power is increasing, and various technologies are being developed. I'm losing.

Liquefied gases, including liquefied natural gas, can remove or reduce air pollutants during the liquefaction process, so they can be viewed as eco-friendly fuels that emit fewer air pollutants during combustion. Accordingly, the consumption of liquefied gas such as liquefied natural gas (LNG) has recently been rapidly increasing worldwide. Liquefied gas, which is made by liquefying gas at low temperature, has a much smaller volume than gas, so it has the advantage of increasing storage and transportation 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 of that of natural gas. Therefore, when natural gas is liquefied and transported, it can be transported very efficiently.

The liquefaction temperature of liquefied petroleum gas varies depending on its composition, but in the case of petroleum gas containing propane as the main ingredient, it is liquefied at a low temperature of about -42℃ at normal pressure, and at a temperature of about 45℃ at 18 bar, and at 20℃ at 7 bar. It can be saved as a state.

Meanwhile, conventional LPG carriers, etc., adopt a fuel supply system that uses relatively inexpensive heavy oil such as bunker C oil as propulsion fuel for ships. This heavy oil fuel supply system has the international exhaust gas emissions associated with the use of heavy oil fuel. Due to strengthened regulations, a separate low-sulfur heavy fuel fuel tank (LSHFO tank) had to be installed, and the demand for an eco-friendly fuel supply system that meets international environmental regulation standards has increased.

Recently, the application of fuel supply systems that use LPG or LNG and boil-off gas generated therefrom as propulsion fuel has been increasing in LPG or LNG carriers, and in accordance with the strengthening of international exhaust gas emission regulations, in addition to LPG or LNG carriers, general ships also use LNG. The number of ships using propulsion fuel is increasing.

In particular, LPG is easier to store than LNG, which is liquefied at extremely low temperatures, and does not fall significantly in SPECIFIC ENERGY and ENERGY DENSITY compared to existing HFO, and has excellent savings in SOX, NOX, CO2, and PM compared to existing HFO.

Although LNG and LPG are considered eco-friendly fuels compared to other fossil fuels previously used as ship fuels, they still produce carbon dioxide when burned, and ships that use them as fuel still emit carbon dioxide during operation.

As each country's interest in greenhouse gas and air pollutant emissions increases and international environmental regulation standards are rapidly strengthened, research on the development of eco-friendly marine fuel technology and eco-friendly energy transportation technology is also being actively conducted on ships.

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

According to EEDI (Energy Efficiency Design Index), a mandatory carbon dioxide reduction regulation applied by IMO to new ships, the initial EEDI announcement called for a 10% reduction in carbon dioxide emissions in 2015 based on carbon dioxide emissions from 2013 to 2015. EEDI Phase 1 was applied, and it was planned to apply Phase 3 in 2025 by strengthening and applying one step every five years. However, for LPG carriers, EEDI Phase 3 will be applied early from 2022, two years after applying EEDI Phase 2. It is being done. As regulations on carbon dioxide emissions from ships are rapidly being strengthened, it may be difficult to achieve carbon dioxide emissions regulations in the future by using only LNG or LPG as fuel.

Accordingly, various research is being conducted on eco-friendly marine fuel that can reduce carbon dioxide emissions, and further on marine fuel for complete decarbonization. In particular, technologies for ships that can use ammonia, hydrogen, etc. as fuel are being actively researched and developed. there is.

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

This ammonia is easier to store than LNG, and although it is slightly lower in SPECIFIC ENERGY and ENERGY DENSITY compared to existing HFO, it does not emit any carbon dioxide, so it is attracting attention as an eco-friendly marine fuel that can respond to the trend of strengthening international greenhouse gas emission standards.

The present invention supplies ammonia as fuel for ship engines, and safely treats and discharges ammonia vented from the fuel pipe and fuel supply unit when the ammonia fuel supply is interrupted, such as when the ammonia fuel mode of the engine is stopped, in accordance with the overboard emission standards. I would like to suggest a way to do this.

According to one aspect of the present invention for solving the above-described problem, a fuel supply unit for supplying ammonia to the engine in accordance with the fuel supply conditions of the engine in a ship equipped with an engine supplied with ammonia as fuel;

An ammonia water tank filled with water to maintain a certain liquid level or higher and accommodating ammonia vented from the fuel pipe and fuel supply unit of the engine;

A chiller that regulates the temperature of the ammonia water tank by circulating cooling water;

A cooling water circulation line connected from the chiller to the chiller via the ammonia water tank;

A coolant valve provided in the coolant circulation line; and

It includes a gas discharge line for discharging ammonia overboard from the ammonia water tank,

When ammonia discharged from the fuel pipe and fuel supply unit flows into the ammonia water tank, the ammonia water tank is cooled through the chiller to control the amount of ammonia discharged from the ammonia water tank to the gas discharge line. An ammonia exhaust system is provided.

Preferably, a first ventilation fan exhausts air from the fuel supply room where the fuel supply unit is located to the outside of the fuel supply room for ventilation; A second ventilation fan provided for ventilation between the inner and outer pipes of the double pipe provided to prevent water leakage from the fuel pipe disposed in the safety area of the engine room; And an eductor provided in the gas discharge line to transport ammonia discharged from the ammonia water tank, wherein the air discharged from the first ventilation fan or the second ventilation fan is supplied to the eductor as a driving fluid. air), and ammonia is sucked into the eductor from the ammonia water tank by the driving fluid, diluted with the driving fluid, and discharged overboard.

Preferably, a dilution discharge pipe connected from the first and second ventilation fans to the eductor; and a dilution discharge valve provided in the dilution discharge pipe, wherein when the engine is operated on ammonia fuel, the dilution discharge valve is closed so that the air discharged by the first and second ventilation fans is discharged outboard, and ammonia is discharged outboard. When ammonia is discharged from the fuel pipe and fuel supply unit due to fuel supply interruption, the dilution discharge valve is opened and the air discharged by the first and second ventilation fans can be supplied to the driving fluid of the eductor.

Preferably, when the air discharged by the first and second ventilation fans cannot be supplied to the eductor or the ammonia dilution discharge rate from the eductor is increased, compressed air within the ship can be supplied as the driving fluid of the eductor. You can.

Preferably, an ammonia concentration meter provided downstream of the eductor in the gas discharge line; and a concentration control valve provided in the gas discharge line to control the amount of ammonia transferred from the ammonia water tank to the eductor.

Preferably, a level sensor that detects the liquid level in the ammonia water tank; A bubbling unit that sprays compressed air into the ammonia water tank to separate ammonia dissolved in the ammonia water into a gaseous state; And it may further include a control unit that controls the concentration of ammonia discharged overboard through the ammonia water tank and through the gas discharge line.

Preferably, the cooling water cooled in the chiller is supplied to a consumer including a urea tank storing urea to be supplied to the SCR onboard the ship, and after being supplied to the consumer, the high-temperature cooling water returned to the chiller is branched to circulate the cooling water. The temperature of the ammonia water tank can be increased by supplying it to the ammonia water tank through a line.

Preferably, a fuel supply line that supplies ammonia stored in the service tank to the engine; a fuel return line that recovers ammonia not consumed in the engine upstream of the fuel supply unit; And a fuel valve train (FVT) in which a service valve that regulates ammonia supply between the fuel supply line and the fuel return line and the engine is disposed, wherein the fuel supply line and the fuel return line in the fuel valve train are A double block and bleed valve may be installed to control the ammonia supply, respectively.

Preferably, the ammonia water tank includes: a first tank for recovering ammonia discharged from the fuel supply unit; and a second tank for recovering ammonia discharged from the fuel valve train.

Preferably, a first vent line connected from the fuel supply unit to the first tank; a second vent line connected from the fuel valve train to the second tank between a double blocking valve provided in the fuel supply line; a third vent line connected to the second tank between a double blocking valve provided in the fuel return line in the fuel valve train; and a fourth vent line connected to the second tank in the fuel valve train upstream of the double blocking valve of the fuel return line.

Preferably, the eductor includes: a first eductor transporting ammonia discharged from the first tank; and a second eductor for transporting ammonia discharged from the second tank, wherein air discharged from the first ventilation fan is transmitted to the first eductor, and air discharged from the second ventilation fan is transmitted to the first eductor. A driving fluid may be supplied to each of the second eductors.

In the present invention, ammonia, an eco-friendly fuel, is supplied as fuel for marine engines to reduce greenhouse gas emissions during ship operation and meet regulatory standards set by international conventions.

In addition, when the supply of ammonia to the engine is interrupted, ammonia is quickly discharged from the fuel pipe and fuel supply section, then diluted and discharged overboard to ensure safety and meet overboard emission standards.

In particular, when there is no need to operate the fan for ventilation of the fuel supply room and double piping due to the interruption of ammonia fuel supply, the fan is used to supply the driving fluid for the eductor and dilute and discharge the vented ammonia to a low concentration in accordance with the overboard discharge standards. By enabling this, the cost of installing additional equipment can be reduced while increasing the utilization of existing onboard equipment.

1 relates to an ammonia treatment system for a marine engine according to an 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.

Hereinafter, the ship in the present invention refers to all types of ships equipped with an engine that can use ammonia as fuel for the ship's engine. Representative examples include LPG carrier (LNG Carrier), LNG carrier (LNG Carrier), liquid hydrogen carrier, and liquid hydrogen carrier. It may include ships with self-propulsion capabilities, such as carriers and ammonia carriers, as well as offshore structures that do not have propulsion capabilities but are floating at sea.

Engines supplied with ammonia as fuel include those supplied with ammonia as fuel together with other marine fuels such as LNG, LPG, and HFO, and those supplied with ammonia alone as fuel, and engines for ship propulsion and power generation. Includes all engines.

Figure 1 schematically shows an ammonia treatment system for a marine engine according to an embodiment of the present invention.

As shown in Figure 1, the ammonia treatment system of this embodiment is a ship equipped with an engine (E) that receives ammonia, and supplies ammonia fuel to the engine in accordance with fuel supply conditions such as pressure and temperature required by the engine. The supply section (LFS) is filled with water to maintain a certain level or higher and includes ammonia water tanks (AT1, AT2) that store ammonia water generated by receiving ammonia venting from the fuel pipe and fuel supply section.

First, looking at the supply of fuel to a marine engine, in the system of this embodiment, a service tank (ST) is provided to store ammonia to be supplied as fuel to the marine engine, and a fuel supply line (FSL) is connected from the service tank to the engine.

In the service tank (ST), ammonia is stored in a liquid state. For example, liquefied ammonia can be stored at room temperature by pressurizing it to around 5 to 20 bar. The service tank may be equipped with a safety valve (SV) to prevent tank pressure from rising.

Ammonia stored in the service tank is supplied to the engine (E) along the fuel supply line (FSL) through the transfer pump (10), and fuel is supplied to the fuel supply line according to fuel supply conditions such as pressure and temperature required by the engine. A fuel supply section (LFS) is established to supply fuel.

The fuel supply unit (LFS) includes a compression pump (20) that compresses the ammonia transferred from the transfer pump to the pressure required by the engine, and a temperature controller (30) that heats or cools the fuel compressed in the compression pump to adjust the temperature required by the engine. ), a filter (40) is provided to filter out foreign substances contained in the fuel to protect the engine.

Liquid ammonia supplied from the service tank through a transfer pump is, for example, compressed to around 50 to 85 bar in a compression pump, adjusted to a temperature of around 45°C through a temperature controller, filtered out of foreign substances, and then delivered to the engine as a high-pressure liquid. It is supplied, and the engine can be operated by hydraulically injecting it into the nozzle at a pressure of 600 to 700 bar.

When an incompressible fluid with little or no change in volume even when pressure is applied, that is, liquid fuel, is supplied to the engine, excess fuel is supplied to the engine to respond to changes in engine load and prevent cavitation. And among the fuel supplied to the engine, the remaining fuel after being consumed is recovered upstream of the engine.

For this purpose, the system of this embodiment is provided with a fuel return line (FRL) that recovers ammonia not consumed by the engine upstream of the fuel supply section, and the fuel return line is provided from the engine to the upstream of the fuel supply section, for example, the service tank (ST). It can be connected to .

If the fuel supply line and fuel return line pass through the safety area of the engine room, they may be configured as double piping (DL) to prevent danger in case of ammonia leaking from the piping.

These double pipes receive ventilation air from outside and circulate the air about 30 times per hour for ventilation, and the fuel supply room (FSR) where the fuel supply unit and fuel pipes are located also uses air for ventilation. It must be circulated. For this purpose, a first ventilation fan (200A) capable of venting the entire fuel supply room to exhaust air from the fuel supply room to the outside of the fuel supply room, and a double ventilation fan (200A) to prevent water leakage from the fuel pipe located in the safety area of the engine room. A second ventilation fan (200B) is provided for ventilation between the inside and outside of the pipe (DL). Two or more first and second ventilation fans may be provided so that even if one fails, the other fan can operate.

Meanwhile, service valves are placed in the fuel valve train (FVT) to control ammonia supply between the fuel supply line and fuel return line and the engine, and the ammonia supply is adjusted to the fuel supply line and fuel return line in the fuel valve train, respectively. To this end, double block and bleed valves (DV1, DV2, DV3, DV4) are installed to supply ammonia to the engine and prevent ammonia fuel supply from being interrupted due to the engine's fuel oil change, ammonia fuel mode stop, trip, etc. In such cases, each pipe is double blocked and the ammonia in the pipe is discharged to the outside to relieve pressure and replace it with nitrogen gas to eliminate the risk of explosion. However, ammonia discharged from the fuel supply section and each piping cannot be discharged to the outside as is due to its toxicity, and recent rules established by the classification society allow discharge overboard at less than 30 PPM.

In the system of this embodiment, water is filled to maintain above a certain level so that the ammonia discharged from the fuel supply unit and each pipe can be diluted and discharged overboard in accordance with the discharge standard, and is vented from the fuel pipe and fuel supply unit. Ammonia water tanks (AT1, AT2) were prepared to store ammonia water produced by receiving ammonia.

This ammonia water tank may include a first tank (AT1) for recovering ammonia discharged from the fuel supply unit (LFS) and a second tank (AT2) for recovering ammonia discharged from the fuel valve train (FVT).

The first vent line (VL1) is connected from the fuel supply unit (LFS) to the first tank (AT1), and the first vent line (VL1) is connected from the fuel valve train (FVT) to the double block valves (DV1, DV2) provided in the fuel supply line (FSL). 2 The second vent line (VL2) is connected to the tank (AT2), and the third vent is connected to the second tank (AT2) between the double block valves (DV3, DV4) provided in the fuel return line (FRL) in the fuel valve train (FVT). The line VL3 is connected to the second tank AT2 upstream of the double blocking valve of the fuel return line FRL in the fuel valve train FVT, and the fourth vent line VL4 is connected. The first to fourth vent lines are provided with venting valves (VV1, VV2, VV3, and VV4) to control ammonia discharge to the first or second tank, respectively.

For example, when the engine's ammonia fuel mode is stopped, the double blocking valves (DV1, DV2, DV3, DV4) of the fuel supply line and fuel return line are closed and the venting valves (VV2, VV3) of the second and third vent lines are opened. Ammonia is released into the second tank (AT2) through the second and third vent lines (VL2, VL3) to relieve the pressure between the valves, and the venting valves (VV1, VV4) of the first and fourth vent lines are opened. Ammonia remaining in the fuel supply unit (LFS) and engine can be discharged to the first and second tanks, respectively.

Ammonia discharged from the fuel supply unit and each pipe is discharged into the first and second tanks filled with low-temperature water and dissolves in water to create ammonia water. Only a small amount of ammonia gas that is not dissolved in water is connected to the gas discharge line to the ammonia water tank. It can be discharged first through (GL1, GL2). To this end, the ammonia water tank, that is, the first and second tanks, is filled with water to maintain a certain liquid level or higher, and the temperature of the ammonia water tank is controlled by circulating cooling water through a chiller (100). The first and second tanks are provided with level sensors (LS1, LS2) that detect the liquid level in the ammonia water tank, and the first and second tanks are filled with water to continuously maintain the liquid level above the level sensor.

Coolant circulation lines (CL1, CL2) are provided from the chiller 100 to the chiller via ammonia water tanks (AT1, AT2), and coolant valves (Cv1, CV2) that open and close the coolant circulation lines are provided in the coolant circulation lines. . Ammonia has very high solubility in water, and in particular, the lower the temperature, the higher the solubility. Therefore, by circulating the cooling water cooled in the chiller to the ammonia water tank through the cooling water circulation line to lower the temperature of the water in the first and second tanks, the solubility of ammonia is increased. It can be raised.

Meanwhile, gas discharge lines (GL1, GL2) are provided to discharge ammonia overboard from the ammonia water tank, and eductors (120A, 120B) are provided in the gas discharge line to transport ammonia discharged from the ammonia water tank.

In particular, in this embodiment, the air discharged from the first ventilation fan (200A) or the second ventilation fan (200B) is supplied to the eductor as a driving fluid, and ammonia is transferred from the ammonia water tank by the driving fluid. It is sucked into the tank and diluted with a large amount of air, which is the driving fluid, so that it can be discharged overboard. For this purpose, dilution discharge pipes (ML1, ML2) are connected from the first and second ventilation fans to the eductor, and dilution discharge valves (MV1, MV2) are provided in the dilution discharge pipes.

The eductor may include a first eductor (120A) for transporting ammonia discharged from the first tank (AT1) and a second eductor (120B) for transporting ammonia discharged from the second tank (AT2). , connecting the dilution discharge pipes (ML1, ML2) from the first ventilation fan (200A) and the second ventilation fan (200B) to the first and second eductors, respectively, so that the discharged air from the first ventilation fan Air can be supplied to the first eductor, and air discharged from the second ventilation fan can be supplied to the second eductor as a driving fluid.

In the ammonia fuel operation mode in which ammonia is supplied to the engine as fuel, the dilution discharge valves (MV1, MV2) are closed and the fuel supply chamber (FSR) and double piping (DL) are vented by the first and second ventilation fans (200A, 200B). The air discharged through ventilation is discharged directly overboard. When discharging the ammonia remaining in the fuel piping and fuel supply due to ammonia fuel supply interruption, open the dilution discharge valves (MV1, MV2) to direct the air transfer direction by the first and second ventilation fans toward the eductors (120A, 120B). By switching, the air blown from the first and second ventilation fans can be supplied as the driving fluid of the eductor. By the driving fluid supplied to the eductor, ammonia gas in the ammonia water tank flows into the eductors (120A, 120B) through the gas discharge lines (GL1, GL2), and a small amount of ammonia gas flowing in passes through the eductor, which is the driving fluid. It is diluted with a large amount of air to meet overboard emission standards. In this way, in this embodiment, when there is no need to operate the fan for ventilation of the fuel supply room and double pipe due to the interruption of ammonia fuel supply, the fan is used to reduce ammonia vented from the fuel pipe and fuel supply section to a low concentration in accordance with the overboard emission standards. It can be diluted and discharged, reducing the cost of installing additional equipment while increasing the utilization of existing equipment on board.

An ammonia concentration meter (GD) is provided downstream of the eductor in the gas discharge line, and a concentration control valve (GV1, GV2) is additionally provided in the gas discharge line to control the amount of ammonia transferred from the ammonia water tank to the eductor. .

In addition, the ammonia water tank is provided with a bubbling unit (110A, 110B) or a vibrator so that the ammonia dissolved in the ammonia water can be separated into a gaseous state by spraying compressed air into the ammonia water tank. By controlling the valves (AV1, AV2), the amount of compressed air supplied to the ammonia tank along the compressed air supply lines (AL1, AL2) and the injection pressure are adjusted to control the amount of bubbling in the bubbling section or the frequency of the vibrator. You can control the amount of ammonia vaporized gas separated from the ammonia water.

If the air discharged by the first and second ventilation fans cannot be supplied to the eductor or if it is desired to increase the ammonia dilution discharge rate from the eductor, the compressed air in the ship can be used as the driving fluid for the eductors (120A, 120B). can be supplied.

Meanwhile, the system of this embodiment is provided with a control unit 300 that controls the concentration of ammonia discharged overboard through the ammonia water tank and through a gas discharge line, and controls equipment including each valve under the control of the control unit to control the ammonia discharged overboard. Concentration can be adjusted.

Looking at the process of discharging the ammonia remaining in the fuel pipe and fuel supply section by the control unit when ammonia supply is interrupted, it can be accomplished as follows.

First, water is injected into the ammonia water tanks (AT1, AT2) as described above to maintain the liquid level above the level sensors (LS1, LS2). When ammonia fuel supply to the engine is stopped, ammonia discharged from the fuel pipe and fuel supply unit flows into the ammonia water tank, and the ammonia water tank is cooled through the chiller 100 to control the amount of ammonia discharged from the ammonia water tank to the gas discharge line. The lower the temperature, the higher the solubility of ammonia in water, so the ammonia discharged into the ammonia water tank dissolves in low-temperature water, and only a small amount of ammonia gas is first discharged from the ammonia water tank to the gas discharge lines (GL1 and GL2). At this time, the control unit 300 opens the concentration control valves (GV1, GV2) and the dilution discharge valves (MV1, MV2) to change the air transport direction of the first and second ventilation fans (200A, 200B) to the eductors (120A, 120B). Then, the air blown from the first and second ventilation fans is supplied as the driving fluid of the eductor, and the ammonia discharged through the gas discharge lines (GL1, GL2) is diluted with the blown air and discharged overboard.

Over time, the control unit adjusts the cooling water valves (CV1, CV2) to stop cooling the ammonia water tank. As a result, the ammonia water tank temperature rises and ammonia vaporization gas is gradually discharged from the ammonia water and discharged through the gas discharge line.

The control unit detects the ammonia concentration of the air to be discharged overboard downstream of the eductor through an ammonia concentration meter (GD), and adjusts the amount of ammonia vaporization gas by adjusting the bubbling amount or vibration frequency of the bubbling unit (110A, 110B) or vibrator accordingly. do. If a ventilation fan cannot be used or if it is desired to further increase the ammonia dilution discharge rate, compressed air can be additionally supplied from the ship's facilities as the driving fluid for the eductor.

At this time, even though the concentration control valves (GV1, GV2) of the gas discharge line are fully opened, if the ammonia concentration measured by the ammonia concentration meter continues to drop and falls significantly below the overboard discharge standard, the ammonia water in the ammonia water tank is vaporized by raising the temperature. The amount of ammonia can be increased.

The coolant cooled in the chiller (100) is supplied to consumers including a urea tank (UT) that stores urea to be supplied to the SCR (400) on board the ship. After being supplied to the consumer, the high-temperature coolant returned to the chiller is branched to provide coolant. The temperature of the ammonia water tank can be increased by supplying it to the ammonia water tank through the circulation lines (CL1, CL2). For this purpose, heating lines (HL1, HL2) are provided to branch the high-temperature coolant recovered from the consumer to the chiller and transfer it to the coolant circulation line, and the heating line and coolant circulation line are equipped with valves to control the supply of high-temperature coolant to the ammonia water tank. (TV1, TV2, TV3) are prepared.

In this way, the amount of ammonia discharged can be reduced by supplying cooling water from the chiller 100 to increase the solubility of ammonia in the ammonia water tank, and the amount of ammonia discharged overboard can be controlled by increasing ammonia discharge through the heating line. High-temperature cooling water recovered from other cooling consumers within the ship can also be used as the heat medium supplied to the cooling water circulation line through the heating line.

When the engine's ammonia mode is stopped, all ammonia can be diluted and discharged, and then the engine can be started again with ammonia fuel oil. At this time, as described above, ammonia can be gradually diluted and discharged in accordance with the overboard discharge standards while controlling the temperature of the ammonia water using a chiller. In addition, when necessary, the blowing direction and blowing volume of the first and second ventilation fans are adjusted through valve control, and some of the ventilation air in the fuel supply room (FSR) and double piping (DL) is discharged as is. Another method is to supply the eductor driving fluid for diluting and discharging ammonia through a dilution discharge valve, and the air of the ventilation fan can be branched into the discharge side and the dilution side and discharged.

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

E: engine
ST: Service tank
FSL: Fuel supply line
FRL: Fuel return line
LFS: Fuel Supply Department
FVT: Fuel valve train
AT1, AT2: Ammonia water tank
CL1, CL2: Coolant circulation line
GL1, GL2: Gas discharge line
100: Chiller
110A, 110B: Bubbling section
120A, 120B; Eductor
200A: 1st ventilation fan
200B: Second ventilation fan
300: Control unit

Claims (11)

A fuel supply unit that supplies ammonia to the engine in accordance with the fuel supply conditions of the engine in a ship equipped with an engine supplied with ammonia as fuel;
An ammonia water tank filled with water to maintain a certain liquid level or higher and accommodating ammonia vented from the fuel pipe and fuel supply unit of the engine;
A chiller that regulates the temperature of the ammonia water tank by circulating cooling water;
A cooling water circulation line connected from the chiller to the chiller via the ammonia water tank;
A coolant valve provided in the coolant circulation line; and
It includes a gas discharge line for discharging ammonia overboard from the ammonia water tank,
When ammonia discharged from the fuel pipe and fuel supply unit flows into the ammonia water tank, the ammonia water tank is cooled through the chiller to control the amount of ammonia discharged from the ammonia water tank to the gas discharge line. ammonia exhaust system. According to clause 1,
a first ventilation fan that exhausts air from the fuel supply room where the fuel supply unit is located to the outside of the fuel supply room for ventilation;
A second ventilation fan provided for ventilation between the inner and outer pipes of the double pipe provided to prevent water leakage from the fuel pipe disposed in the safety area of the engine room; and
It further includes an eductor provided in the gas discharge line to transport ammonia discharged from the ammonia water tank,
The air discharged from the first ventilation fan or the second ventilation fan is supplied to the eductor as a driving fluid, and ammonia is sucked into the eductor from the ammonia water tank by the driving fluid to drive the eductor. An ammonia exhaust system for a marine engine, characterized in that it is diluted in a fluid and discharged overboard. According to clause 2,
a dilution discharge pipe connected from the first and second ventilation fans to the eductor; and
It further includes a dilution discharge valve provided in the dilution discharge pipe,
When the engine is operated on ammonia fuel, the air discharged by the first and second ventilation fans is discharged overboard by closing the dilution discharge valve, and when ammonia is discharged from the fuel pipe and fuel supply unit due to ammonia fuel supply interruption, the dilution discharge is discharged. An ammonia exhaust system for a marine engine, characterized in that the air discharged by the first and second ventilation fans by opening the valve can be supplied to the driving fluid of the eductor. According to clause 3,
When the air discharged by the first and second ventilation fans cannot be supplied to the eductor or the ammonia dilution discharge rate from the eductor is increased, compressed air within the ship can be supplied as the driving fluid of the eductor. Ammonia exhaust system for marine engines. According to clause 3,
An ammonia concentration meter provided downstream of the eductor in the gas discharge line; and
An ammonia discharge system for a marine engine further comprising: a concentration control valve provided in the gas discharge line to control the amount of ammonia transferred from the ammonia water tank to the eductor. According to clause 5,
A level sensor that detects the liquid level in the ammonia water tank;
A bubbling unit that sprays compressed air into the ammonia water tank to separate ammonia dissolved in the ammonia water into a gaseous state; and
An ammonia discharge system for a marine engine further comprising: a control unit that controls the concentration of ammonia discharged overboard through the ammonia water tank and through the gas discharge line. According to clause 6,
The coolant cooled in the chiller is supplied to consumers including a urea tank that stores urea to be supplied to the SCR onboard the ship,
An ammonia discharge system for a marine engine, characterized in that the high-temperature coolant returned to the chiller after being supplied to the consumer is branched and supplied to the ammonia water tank through the coolant circulation line to increase the temperature of the ammonia water tank. According to any one of claims 2 to 7,
A fuel supply line that supplies ammonia stored in the service tank to the engine;
a fuel return line that recovers ammonia not consumed in the engine upstream of the fuel supply unit; and
It further includes a fuel valve train (FVT) in which a service valve that regulates ammonia supply between the fuel supply line and fuel return line and the engine is disposed,
An ammonia treatment system for a marine engine, characterized in that a double block and bleed valve for controlling ammonia supply is installed in the fuel supply line and the fuel return line in the fuel valve train, respectively. The method of claim 8, wherein the ammonia water tank,
A first tank for recovering ammonia discharged from the fuel supply unit; and
Ammonia treatment system for a marine engine comprising: a second tank for recovering ammonia discharged from the fuel valve train. According to clause 9,
a first vent line connected from the fuel supply unit to the first tank;
a second vent line connected from the fuel valve train to the second tank between a double blocking valve provided in the fuel supply line;
a third vent line connected to the second tank between a double blocking valve provided in the fuel return line in the fuel valve train; and
Ammonia treatment system for a marine engine further comprising: a fourth vent line connected to the second tank in the fuel valve train upstream of the double block valve of the fuel return line. The method of claim 9, wherein the eductor is:
A first eductor transporting ammonia discharged from the first tank; and
A second eductor transporting ammonia discharged from the second tank,
Ammonia treatment of a marine engine, characterized in that the air discharged from the first ventilation fan is supplied to the first eductor, and the air discharged from the second ventilation fan is supplied to the second eductor as a driving fluid. system.

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