KR101246902B1 - Engine system using brown gas, ship comprising the same and engine operating method using brown gas - Google Patents

Abstract

An engine system using Brown gas is disclosed. Engine system using Brown gas according to an embodiment of the present invention, the engine; Brown's gas generator to produce Brown's gas; Cold box unit for liquefying the brown gas produced in the brown gas generator; Liquefied brown gas tank for receiving the liquid brown gas from the cold box unit to store; A brown gas heater for heating and vaporizing liquefied brown gas supplied from the liquefied brown gas tank; And a brown gas injector receiving brown gas from the brown gas heater and injecting the brown gas into the engine.

Description

ENGINE SYSTEM USING BROWN GAS, SHIP COMPRISING THE SAME AND ENGINE OPERATING METHOD USING BROWN GAS}

The present invention relates to an engine system using Brown gas, a ship including the same, and a method of driving an engine.

  Today, ships use diesel engines in general. For marine diesel engines, heavy fuel oil (HFO) and marine gas oil (MGO) are used as fossil fuels.

The reduction of greenhouse gases and NOx caused by the burning of fossil fuels has become an important issue due to the strengthening of current environmental regulations, and the clean diesel combustion method has emerged as a new topic for internal combustion engines. In addition, a method of reducing fuel consumption (SFOC), which is a fuel consumption rate, is also very important due to a rise in oil prices due to depletion of fossil fuels.

The blending of brown gas with fossil fuels is a clean diesel combustion method and can reduce SFOC, resulting in environmental regulations and fuel savings.

Brown gas is a type of gas that combines oxygen and hydrogen by electrolyzing water. It is an eco-friendly fuel because water is generated after combustion. It is excellent as a combustion accelerator for fossil fuel and mixed combustion because the flame speed is significantly faster than that of conventional fossil fuel. It works. In addition, since the flammable limit of hydrogen is much greater than that of fossil fuel, it can be used as a flame stabilizer to increase the flammable limit when mixing with fossil fuel.

Brown gas blended engines enable ultra-lean combustion greater than conventional air-fuel ratios, maximizing fuel savings and reducing emissions.

An embodiment of the present invention is to provide an engine system and a method for driving an engine having a configuration capable of stably supplying Brown gas while using a small capacity Brown gas generator.

According to an aspect of the present invention, an engine system using Brown gas,

engine; Brown's gas generator to produce Brown's gas; A cold box unit for liquefying the brown gas produced by the brown gas generator; Liquefied brown gas tank for receiving the liquid brown gas from the cold box unit for storage; A brown gas heater configured to heat and vaporize the liquefied brown gas supplied from the liquefied brown gas tank; And a brown gas injector receiving brown gas from the brown gas heater and injecting the brown gas into the engine.

The gas may further include a brown gas compressor provided between the brown gas heater and the brown gas injector to supply the brown gas supplied from the brown gas heater in a compressed state.

In addition, a brown gas manifold provided between the brown gas compressor and the brown gas injector to receive brown gas compressed from the brown gas compressor and temporarily store the brown gas to supply brown gas with reduced pressure fluctuation. can do.

Further, between the brown gas generator and the cold box unit, between the cold box unit and the liquefied brown gas tank, between the liquefied brown gas tank and the brown gas heater, between the brown gas heater and the brown gas compressor, the brown Brown gas supply pipes may be provided between the gas compressor and the brown gas manifold, and between the brown gas manifold and the brown gas injector.

In addition, the brown gas supply pipe has a double wall structure, and an inert gas may be filled between the double walls.

In addition, a purge gas inlet provided in the Brown gas supply pipe between the Brown gas generator and the cold box unit to clean the flow path of hydrogen gas in the engine system; And a purge gas outlet provided in a brown gas supply pipe between the brown gas manifold and the brown gas injector.

In addition, the brown gas supply pipe provided between the brown gas manifold and the brown gas injector may be provided with a flow control valve for controlling the flow rate of the brown gas supplied to the brown gas injector.

In addition, the engine system is used as a power source of the vessel, the flow control valve is to control the flow rate of the brown gas flowing into the combustion chamber of the engine according to the amount of fossil fuel used in the engine, the flow rate control valve of the vessel ( Governor).

In addition, when the engine system is inoperative or in an emergency situation, the brown gas remaining in at least one of the liquefied brown gas tank, the flow control valve, the brown gas heater, the brown gas compressor, and the brown gas manifold is supplied with It may further include a gas combustion unit for burning.

In addition, the liquefied brown gas tank has a double wall structure, the inert gas may be filled between the double walls.

In addition, the Brown gas injector may be mounted to the cylinder head of the engine to directly inject Brown gas into the combustion chamber of the engine.

In addition, the brown gas injector may be mounted to an intake port for guiding intake air into the combustion chamber of the engine to inject brown gas into the intake port.

In addition, the brown gas heater may be vaporized by heating the brown gas liquefied with the steam produced by using the waste heat of the exhaust gas of the engine.

According to another aspect of the invention, there can be provided a vessel comprising; an engine system using the brown gas described above.

According to another aspect of the present invention, as a driving method of an engine using Brown gas,

Brown gas production step of producing Brown gas; A brown gas cooling step of liquefying the brown gas produced in the brown gas production step; Liquefied brown gas storage step of receiving the liquefied brown gas supplied in the brown gas cooling step and stored in the liquefied brown gas tank; A brown gas heating step of receiving liquefied brown gas from the liquefied brown gas tank and heating it to convert brown gas into a gaseous brown gas; And a brown gas injection step of injecting the heated brown gas into the engine. The driving method of the engine using brown gas may be provided.

The gas may further include a brown gas compression step of compressing the heated brown gas and supplying the heated brown gas to the engine between the brown gas heating step and the brown gas injection step.

According to the engine system using the brown gas according to the present embodiment, a ship and an engine driving method including the same, the brown gas is liquefied and stored in advance, if necessary, is heated and vaporized, and the vaporized brown gas is stored in the combustion chamber of the engine. By supplying, brown gas can be stably supplied to the combustion chamber of an engine, using a small capacity brown gas generator.

1 is a schematic diagram of an engine system using Brown gas according to an embodiment of the present invention.
2 is a cross-sectional view of a brown gas supply pipe in the engine system of FIG. 1.
3 is a cross-sectional view of a liquefied brown gas tank in the engine system of FIG.
4 is a view for explaining the mounting position of the Brown gas injector in the engine system of FIG.
5 is a view for explaining another mounting position of the Brown gas injector in the engine system of FIG.
6 is a view in which a purge gas inlet and a purge gas outlet are added to the engine system of FIG. 1.
FIG. 7 is a view for explaining a case where a gas combustion unit is added in the engine system of FIG. 1.
8 is a schematic flowchart of a method of driving an engine using Brown gas according to an embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. The present embodiments are not intended to be limiting.

1 is a schematic diagram of an engine system using Brown gas according to an embodiment of the present invention.

Referring to FIG. 1, the engine system 100 using the illustrated Brown gas is used for, for example, an engine used in a propulsion engine such as a ship or a power generation plant. The engine system 100 includes an engine 10 (shown in FIG. 4), a brown gas generator 110, a cold box unit 120, a liquefied brown gas tank 150, a brown gas heater 156, and a brown gas compressor ( 164, Brown gas manifold 170, and Brown gas injector 190.

The engine 10 is driven by mixing fossil fuels of heavy fuel oil (HFO) or marine gas oil (MGO) with brown gas produced by the brown gas generator 110.

The brown gas generator 110 is provided to produce brown gas by electrolyzing water.

Here, Brown gas, as is well known, is a gas in which hydrogen and oxygen generated by electrolysis of water quantitatively coexist in a ratio of 2 to 1, and contain self-contained suitable oxygen for complete combustion, thereby becoming a next generation fuel. I am getting it. In particular, compared with conventional fossil fuels, Brown gas has a good temperature rising property in which the temperature rises rapidly during combustion, and has a high adiabatic flame temperature and a flame speed that is remarkably fast. In addition, Brown gas is a clean energy source that is essentially free of environmental pollution since only water vapor is generated after complete combustion.

The brown gas produced by the brown gas generator 110 is sent to the cold box unit 120 through the brown gas supply pipe 112. 2 is a cross-sectional view of a brown gas supply pipe in the engine system of FIG. 1.

As shown in FIG. 2, the brown gas supply pipe 112 has a double wall structure of an inner wall 112a and an outer wall 112b. In addition, Brown gas is transferred to the inner wall 112a, and an inert gas G is filled between the inner wall 112a and the outer wall 112b.

Since the brown gas supply pipe 112 has a double wall structure and an inert gas is filled between the double walls, the brown gas supply pipe 112 may prevent the hydrogen gas component of brown gas from being discharged from the brown gas supply pipe 112 to the outside and explode. Can be. In addition, the liquefied gas pipe 131 and the brown gas supply pipes 144, 165, and 172 to be described later have a double wall structure similar to the brown gas supply pipe 112.

The cold box unit 120 is provided to liquefy the brown gas produced by the brown gas generator 110. The cold box unit 120 includes one or more heat exchangers 122, one or more compressors 124, one or more coolers 126, one or more expanders 128, a refrigerant circulation passage 123, and a gas-liquid separator 127. ).

The refrigerant flows through the refrigerant circulation passage 123 through the heat exchanger 122, the compressor 124, the cooler 126, and the expander 128. After the refrigerant in the compressor 124 is compressed adiabatic, the refrigerant is cooled through heat exchange while maintaining a constant pressure in the cooler 126.

In the present embodiment, the cooler 126 may cool the refrigerant by cold sea water. Then, the refrigerant cooled in the cooler 126 is adiabatic expansion in the expander 128 is cooled to cryogenic temperatures. The inflator 128 may be, for example, an expansion turbine. The refrigerant cooled to cryogenic temperature is introduced into the heat exchanger 122 through the refrigerant circulation passage 123. In the heat exchanger 122, a brown gas transport pipe 113 connected to the brown gas supply pipe 112 and a refrigerant circulation passage 123 are provided. In the heat exchanger 122, the brown gas and the refrigerant perform mutual heat exchange, whereby the brown gas is cooled.

In this case, the brown gas is cooled below the boiling point of hydrogen in the heat exchanger 122. Thus, the brown gas is changed into a liquid state. Therefore, the brown gas liquefied in the gas-liquid separator 127 is supplied to and stored in the liquefied brown gas tank 150 through the liquefied gas pipe 131. Since the brown gas is liquefied and stored in the liquefied brown gas tank 150, the volume of the liquefied brown gas tank 150 may be reduced. Meanwhile, the brown gas of the gaseous phase in the gas-liquid separator 127 is resupplied to the brown gas transport pipe 113 through the brown gas resupply pipe 125 and continuously cooled in the heat exchanger 122.

In the present embodiment, the compressor 124 and the cooler 126 are described as an example, but a plurality of each is provided with a plurality of stages of compression and cooling may of course repeat. In addition, for the cryogenic expansion of the working fluid, the expander 128 may use an expansion valve instead of an expansion turbine.

Next, the flow of Brown gas will be described.

3 is a cross-sectional view of a liquefied brown gas tank in the engine system of FIG.

Referring to FIG. 3, the liquefied brown gas tank 150 has a double wall structure having an inner wall 150a and an outer wall 150b. On the other hand, the liquefied brown gas tank 150 is provided with an inlet valve 151 for adjusting the inflow amount of the liquefied brown gas and an outlet valve 152 for adjusting the outflow amount of the liquefied brown gas. In addition, a liquefied brown gas is stored inside the inner wall 150a, and an inert gas G is filled between the inner wall 150a and the outer wall 150b. Since the liquefied brown gas tank 150 has a double wall structure and an inert gas is filled between the double walls, the liquefied brown gas tank 150 is insulated, and the liquefied brown gas tank 150 is liquefied brown gas. Is discharged to the outside to prevent the risk of explosion of hydrogen in Brown gas.

The hydrogen gas stored in the liquefied brown gas tank 150 is then discharged through the outlet valve 152 in an amount necessary at a necessary time, and then transported to the brown gas heater 156 through the brown gas supply pipe 144. do.

The brown gas heater 156 is provided to heat and vaporize the liquefied brown gas transported from the liquefied brown gas tank 150.

The brown gas heater 156 is provided with a brown gas supply pipe 144 and a steam pipe 157 through which steam flows. In the brown gas heater 156, the liquefied brown gas is vaporized by mutually exchanging liquefied brown gas and steam.

On the other hand, the steam is produced by heating the water using the heat of the exhaust gas discharged from the combustion chamber 14 of the engine 10 (see FIG. 4). That is, in this embodiment, energy efficiency is improved by producing steam using waste heat of the engine 10 and vaporizing liquefied brown gas using the steam.

The engine system 100 using the brown gas according to the present embodiment may further include a brown gas compressor 164 and a brown gas manifold 170.

Brown gas heated in the brown gas heater 156 is supplied to the brown gas compressor 164.

The brown gas compressor 164 is provided to compress the brown gas vaporized by the brown gas heater 156 to a high pressure.

Since the brown gas is pressurized by the brown gas compressor 164, the atomization of the brown gas injected into the combustion chamber 14 of the engine 10 may be promoted.

The brown gas pressurized by the brown gas compressor 164 is supplied to the brown gas manifold 170 through the brown gas supply pipe 165. The brown gas manifold 170 is provided to temporarily store the pressurized brown gas to reduce pressure fluctuation and maintain the pressure at a constant pressure.

Brown gas temporarily stored in the brown gas manifold 170 is supplied to the brown gas injector 190 through the brown gas supply pipe 172.

The brown gas supply pipe 172 is provided with a flow control valve 180. The flow control valve 180 is provided to adjust the flow rate of the brown gas supplied from the brown gas manifold 170 to the brown gas injector 190.

In this case, the flow control valve 180 is connected with a speed controller (Governor) 101 of the ship to adjust the flow rate of the brown gas flowing into the combustion chamber of the engine according to the amount of fossil fuel used as fuel in the engine of the ship. Can be controlled.

Hereinafter, the mounting of the Brown gas injector 190 will be described with reference to FIG. 4. 4 shows an engine 10 used in the engine system 100 according to the present embodiment.

The combustion chamber 14 of the engine 10 is provided in the form of a space partitioned by the cylinder head 17, the cylinder block 12, and the piston 11. In addition, in order to guide the inflow of air into the combustion chamber 14 of the engine 10, an intake port 15 in fluid communication with the combustion chamber 14 is provided. The air introduced into the intake port 15 is combusted together with fuel in the combustion chamber 14 and then discharged through the exhaust port 16 in fluid communication with the combustion chamber 14.

On the other hand, the cylinder head 17 is equipped with a fuel injector 102 for injecting fossil fuel into the combustion chamber 14. In addition, the intake port 15 is equipped with the Brown gas injector 190. As described above, the fuel injector 102 and the Brown gas injector 190 are controlled by the speed controller 101 of the ship.

Brown gas injected into the intake port 15 is mixed with intake air and then flows into the combustion chamber 14.

The mixture of brown gas and intake air sucked into the combustion chamber 14 is combusted with fossil fuel injected from the fuel injector 102. Since the fossil fuel and the brown gas are mixed together in the combustion chamber 14, lean burning is possible. Therefore, it is possible to reduce contaminants in the exhaust gas and to improve fuel economy.

In the present exemplary embodiment, the brown gas injector 190 is mounted on the intake port 15, for example. However, as illustrated in FIG. 5, the brown gas injector 190 is the fuel injector 102. ) May be mounted on the cylinder head 17 to directly inject Brown gas into the combustion chamber 14.

The engine system 100 using Brown gas according to the present exemplary embodiment may further include a purge gas inlet 175 and a purge gas outlet 173.

6 is a view in which a purge gas inlet and a purge gas outlet are added to the engine system of FIG. 1.

Referring to FIG. 6, the engine system 100 includes a purge gas inlet 175 provided in the brown gas supply pipe 112, and the brown gas manifold 170 and the brown to clean a gas flow path. It includes a purge gas outlet 173 provided in the Brown gas supply pipe 172 between the gas injector 190. In addition, the purge gas inlet 175 is provided with a flow control valve 176 for adjusting the flow rate of the purge gas to be introduced. In addition, the purge gas outlet 173 is provided with a flow control valve 174 for adjusting the flow rate of the purge gas to be discharged.

When the engine system 100 is not used or in an emergency situation in which the engine system 100 is not normally operated, hydrogen components of brown gas remaining in the brown gas flow path of the engine system 100 may explode. . Therefore, to prevent this, when the engine system 100 is not in use or in an emergency, the flow control valve 176 is opened to purge gas to the Brown gas supply pipe 112 through the purge gas inlet 175. Inflow. The introduced purge gas removes the brown gas remaining in the brown gas flow path. That is, the introduced purge gas is from the brown gas supply pipe 112, the brown gas transport pipe 113, the gas-liquid separator 127, the liquefied gas pipe 131, the liquefied brown gas tank 150, and the brown gas heater 156. ), The brown gas compressor 164, the brown gas supply pipe 165, the brown gas manifold 170, and the brown gas supply pipe 172 are sequentially passed through the purge gas outlet 173.

As described above, according to the engine system 100 using the brown gas according to the present embodiment, by employing a small capacity brown gas generator, the brown gas is liquefied and stored in advance when the surplus power is generated, Vaporized and vaporized brown gas may be supplied to the combustion chamber of the engine.

Therefore, it is possible to stably supply Brown gas while using a small capacity Brown gas generator, thereby increasing the flammability limit of the engine.

In addition, there is an advantage that does not need to have a large capacity brown gas generator in order to supply brown gas to a large engine such as an engine of a ship.

FIG. 7 is a view for explaining a case where a gas combustion unit 163 is added in the engine system of FIG. 1.

In an emergency situation in which the engine system 100 is not normally operated, the liquefied brown gas tank 150, the flow control valve 180, the brown gas heater 156, and the brown gas manifold 170 may Brown gas remains and there is a risk of explosion. The gas combustion unit 163 is supplied with the residual brown gas and combusted to prevent an accident due to the explosion of the brown gas in advance.

In the above-described embodiment, the Brown gas engine system 100 has been described as an example including the Brown gas compressor 164 and the Brown gas manifold 170. However, the Brown gas engine system does not have a Brown gas compressor and a Brown gas manifold, but may also be configured such that Brown gas is supplied directly from the Brown gas heater 156 to the Brown gas injector 190.

Hereinafter, a driving method of an engine using brown gas according to the present embodiment will be described.

8 is a schematic flowchart of a method of driving an engine using Brown gas according to an embodiment of the present invention.

The engine driving method using the brown gas, brown gas production step (S101), brown gas cooling step (S102), liquefied brown gas storage step (S103), brown gas heating step (S104), brown gas compression step (S105) ) And a fuel injection step (S106).

In the brown gas production step (S101), water is electrolyzed to produce brown gas.

In the brown gas cooling step (S102), the brown gas produced in the brown gas production step (S101) is liquefied.

In the liquefied brown gas storage step (S103), the brown gas liquefied in the brown gas cooling step (S102) is supplied and stored in the liquefied brown gas tank.

In the brown gas heating step (S104), the liquefied brown gas is supplied from the liquefied brown gas tank and heated to convert the brown gas into a gaseous brown gas.

In the brown gas compression step S105, the vaporized brown gas is compressed at a high pressure.

In the fuel injection step (S106), the brown gas pressurized in the brown gas compression step (S105) is injected into the combustion chamber of the engine.

The present invention described above is not limited to the above-described embodiment and the accompanying drawings. It will be apparent to those skilled in the art that various modifications and changes can be made without departing from the technical spirit of the present invention.

Description of the Related Art
10: engine 11: piston
12: cylinder block 14: combustion chamber
15: intake port 16: exhaust port
17: cylinder head 100: engine system
101: speed regulator 102: fuel injector
110: Brown gas generator 112: Brown gas supply pipe
113: Brown gas pipeline 120: Cold box unit
150: liquefied brown gas tank 156: Brown gas heater
163: gas combustion unit 164: Brown gas compressor
170: Brown gas manifold 173: purge gas outlet
175: purge gas inlet 180: flow control valve
190: hydrogen gas injector

Claims (16)

As an engine system using Brown gas,
engine;
Brown's gas generator to produce Brown's gas;
A cold box unit for liquefying the brown gas produced by the brown gas generator;
Liquefied brown gas tank for receiving the liquid brown gas from the cold box unit for storage;
A brown gas heater configured to heat and vaporize the liquefied brown gas supplied from the liquefied brown gas tank;
A brown gas compressor for supplying the brown gas supplied from the brown gas heater in a compressed state;
A brown gas manifold for supplying brown gas in a state in which the compressed brown gas is temporarily stored by receiving the compressed brown gas from the brown gas compressor to reduce pressure fluctuations; And
And a brown gas injector receiving the brown gas from the brown gas manifold and injecting the brown gas into the engine. delete delete The method according to claim 1,
Between the brown gas generator and the cold box unit, between the cold box unit and the liquefied brown gas tank, between the liquefied brown gas tank and the brown gas heater, between the brown gas heater and the brown gas compressor, the brown gas compressor And a brown gas supply pipe between the brown gas manifold and the brown gas manifold and the brown gas injector, respectively. The method of claim 4,
The brown gas supply pipe has a double wall structure,
An engine system using Brown's gas, characterized in that the inert gas is filled between the double wall. The method of claim 4,
In order to clean the flow passage of hydrogen gas in the engine system,
A purge gas inlet provided in a brown gas supply pipe between the brown gas generator and the cold box unit; And
And a purge gas outlet provided in a brown gas supply pipe between the brown gas manifold and the brown gas injector. The method of claim 4,
The brown gas supply pipe provided between the brown gas manifold and the brown gas injector is provided with a flow control valve for adjusting the flow rate of the brown gas supplied to the brown gas injector. The method of claim 7,
The engine system is used as a power source of the ship,
In order to adjust the flow rate of the brown gas flowing into the combustion chamber of the engine according to the amount of fossil fuel used in the engine, the flow control valve using a brown gas, characterized in that associated with the speed governor (Governor) of the vessel Engine system. The method of claim 7,
In case of inactivity or emergency of the engine system,
And a gas combustion unit configured to receive the brown gas remaining in at least one of the liquefied brown gas tank, the flow control valve, the brown gas heater, the brown gas compressor, and the brown gas manifold. Engine system using Brown gas. The method according to any one of claims 1 or 4 to 9,
The liquefied brown gas tank has a double wall structure,
An engine system using Brown's gas, characterized in that the inert gas is filled between the double wall. The method according to any one of claims 1 or 4 to 9,
And the brown gas injector is mounted to a cylinder head of the engine to directly inject brown gas into the combustion chamber of the engine. The method according to any one of claims 1 or 4 to 9,
The brown gas injector is mounted to an intake port for guiding intake air into the combustion chamber of the engine to inject brown gas into the intake port. The method according to any one of claims 1 or 4 to 9,
The brown gas heater is an engine system using brown gas, characterized in that to heat and vaporize the brown gas liquefied by the steam produced using the waste heat of the exhaust gas of the engine. A ship comprising; an engine system using the brown gas according to any one of claims 1 to 4. As a driving method of an engine using Brown gas,
Brown gas production step of producing Brown gas;
A brown gas cooling step of liquefying the brown gas produced in the brown gas production step;
Liquefied brown gas storage step of receiving the liquefied brown gas supplied in the brown gas cooling step and stored in the liquefied brown gas tank;
A brown gas heating step of receiving liquefied brown gas from the liquefied brown gas tank and heating it to convert brown gas into a gaseous brown gas;
A brown gas compression step of compressing the heated brown gas;
A brown gas supplying step of temporarily storing the compressed brown gas in a brown gas manifold and supplying the compressed brown gas with a reduced pressure fluctuation; And
Brown gas injection step of injecting the brown gas supplied from the brown gas manifold to the engine. delete

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