KR101302006B1 - Apparatus and Method for Supplying Fuel Gas of Ship Engine - Google Patents

Abstract

The present invention relates to a fuel supply apparatus of a marine engine for minimizing the generation of nitrogen oxides, according to an embodiment of the present invention, the main fuel supply line for extracting the LNG from the LNG storage tank and supply to the marine engine, the LNG storage tank Reform fuel supply line for supplying natural gas to the reformer from the reformer, a reformer (reformer) for generating hydrogen gas from the natural gas supplied from the reforming fuel supply line receives the steam supplied separately and from the main fuel supply line Disclosed is a fuel supply apparatus for a marine engine, comprising a manifold for mixing vaporized LNG and hydrogen gas generated in the reformer and supplying the gas to the marine engine.

Description

Apparatus and Method for Supplying Fuel Gas of Ship Engine}

The present invention relates to a fuel supply apparatus and method for a marine engine, and more particularly, to produce hydrogen gas from natural gas, and mix it with natural gas to supply the engine to improve the ignition performance of the engine and minimize the generation of nitrogen oxides. It relates to a fuel supply device and a method of a marine engine.

In general, natural gas is produced in the form of liquefied natural gas (Liquefied Natural Gas, hereinafter referred to as 'LNG') at a cryogenic temperature of -163 ° C at the production site, and then transported to a destination by an LNG carrier over a long distance.

Since the liquefaction temperature of natural gas is extremely low, LNG will evaporate even if the temperature rises slightly. Although LNG storage tanks equipped with LNG carriers are insulated, the external heat is continuously transferred into the LNG storage tanks, so LNG is continuously vaporized during the transportation of LNG and the evaporated gas in the LNG storage tanks. (Boil-Off Gas: BOG) occurs.

As such, when the boil-off gas accumulates in the LNG storage tank, the pressure in the LNG storage tank is excessively increased, so that the boil-off gas is used as a fuel of a ship propulsion engine or in a gas combustor to treat the boil-off gas generated in the LNG storage tank. Incineration or part is reliquefied and reflowed into LNG storage tanks.

In recent years, development of a supply device for reliquefaction of BOG while using LNG as a main fuel of a marine propulsion engine has been actively performed.

Referring to Figure 1, the configuration of a conventional LNG fuel supply and re-liquefaction apparatus is as follows.

As shown in FIG. 1, the conventional fuel supply and reliquefaction apparatus is provided with a fuel gas supply line L1 which extracts LNG from an LNG storage tank 1 of an LNG carrier and supplies it to a marine engine. In the middle of the line L1, the heat exchanger 3 which heat-exchanges LNG with the boil-off gas extracted from the LNG storage tank 1 is provided.

The fuel gas supply line L1 upstream of the heat exchanger 3 is provided with a primary pump 2 for supplying LNG to the marine engine by compressing the LNG to the required pressure of the marine engine.

In the heat exchanger 3, an evaporation gas liquefaction line L2 through which the evaporation gas is withdrawn from the upper portion of the LNG storage tank 1 and is returned to one side of the LNG storage tank 1 is passed.

In the heat exchanger (3), the LNG is raised by heat exchange with the boil-off gas and supplied to the marine engine, and the boil-off gas is liquefied by heat-exchange with the LNG and returned to the LNG storage tank (1).

Fuel pump supply line (L1) downstream of the heat exchanger (3) is a secondary pump (4) for supplying to the marine engine by compressing LNG heat exchanged with the boil-off gas in the heat exchanger (3) to the required pressure of the marine engine (4) ) Is installed.

The fuel gas supply line L1 downstream of the secondary pump 4 is provided with a heater 5 for heating the LNG heat-exchanged in the heat exchanger 3 and supplying it to the marine engine.

In the boil-off gas liquefaction line (L2) upstream of the heat exchanger (3), the compressor (6) and the cooler (7) for the boil-off gas are installed in order to compress and cool the boil-off gas extracted from the LNG storage tank and then heat-exchange with the LNG. It is.

In order to control the pressure of the fluid passing through the primary pump (2), the secondary pump (4), the compressor for the boil-off gas (6) and the cooler (7), a flow regulating pressure regulating valve (11) is provided for each device. It is.

In addition, in the fuel gas supply line L1 before and after the heater 5, in order to adjust the temperature of the fluid which passes through a line, the flow regulating temperature control valve 12 is installed in parallel.

Fuel gas supply line L1 downstream of the primary pump 2, fuel gas supply line L1 downstream of the secondary pump 4, downstream of the compressor 6 and the cooler 7 for the boil-off gas. The pressure sensor 13 is connected between the boil-off gas liquefaction line L2 and each of the pressure regulating valves 11. In addition, a temperature sensor 15 is connected between the fuel gas supply line L1 downstream of the heater 5 and the temperature control valve 12.

The flow regulating pressure regulating valve 11 and the temperature regulating valve 12 adjust the pressure or temperature of the fluid passing by adjusting the flow rate. In addition, an expansion type pressure regulating valve 12a is provided in the middle of the boil-off gas liquefaction line L2 downstream of the heat exchanger 3 to control the pressure of the fluid passing therethrough.

A pressure sensor 13 is also connected between the boil-off gas liquefaction line L2 and the pressure control valve 12a in front of the pressure control valve 12a installed in the boil-off gas liquefaction line L2 downstream of the heat exchanger 3. have.

However, the conventional conventional fuel supply and reliquefaction apparatus described above has a limitation in that a large amount of nitrogen oxides are generated by using natural gas as the main fuel.

Recently, there is a high interest in environmentally friendly engine technology, and in particular, the reduction of nitrogen oxides generated by engine combustion has become a very sensitive issue. Therefore, there is a need to further reduce nitrogen oxides in engines using LNG. A large amount of nitrogen oxides are caused by a high temperature in the engine combustion chamber, and a method for lowering the flammable limit is required for a stable combustion reaction while lowering the combustion temperature.

The present invention is to solve the conventional problems as described above, to provide an environmentally friendly marine fuel supply device and method for improving the ignition performance of the engine and minimize the generation of nitrogen oxides.

In order to solve the above problems, according to an embodiment of the present invention, the main fuel supply line for extracting LNG from the LNG storage tank and supplying it to the marine engine, supplying natural gas to the reformer (reformer) from the LNG storage tank Reforming fuel supply line, reforming reaction unit for receiving a separately supplied steam to generate a mixed gas containing hydrogen gas and carbon monoxide from the natural gas supplied from the reforming fuel supply line, the mixture generated from the reforming reaction unit In the reformer (reformer) and the main fuel supply line including a carbon monoxide reduction unit for reducing the concentration of carbon monoxide contained in the mixed gas and a reaction space therein to accommodate the reforming reaction unit and maintaining a high temperature state For the vessel by mixing the vaporized LNG supplied and the hydrogen gas generated from the reformer A fuel supply apparatus for a marine engine including a manifold for supplying an engine is disclosed.

The reformer may be configured to generate hydrogen gas through a reforming catalytic reaction by thermal energy.

delete

delete

The fuel supply apparatus according to an embodiment of the present invention may further include a steam generator provided in the reaction space to change the water supplied from the outside into steam using a high temperature state inside the reaction space.

The reformer may include a combustion burner that supplies heat into the reaction space by a combustion reaction by natural gas supplied from the LNG storage tank and air supplied from the outside.

The carbon monoxide reduction unit may include a high temperature conversion reaction unit using a high temperature water gas conversion catalyst and a low temperature conversion reaction unit using a low temperature water gas conversion catalyst.

The steam generated in the steam generator may be configured to be supplied to each of the high temperature conversion reaction unit and the low temperature conversion reaction unit. In addition, a first heat exchanger is provided during the main fuel supply line, and may further include an boil-off gas liquefaction line which removes the boil-off gas from the upper portion of the LNG storage tank, passes through the first heat exchanger, and is connected to the LNG storage tank again. .

Alternatively, the boil-off gas liquefaction line may be configured to withdraw the boil-off gas from the top of the LNG storage tank and pass through the first heat exchanger and connected downstream of the first heat exchanger of the main fuel supply line.

Here, a boil-off gas compressor may be installed in the boil-off gas liquefaction line.

In addition, a second heat exchanger may be provided downstream of the compressor for the boil-off gas in the boil-off gas liquefaction line, and downstream of the compressor for the boil-off gas may be configured such that water supplied from the outside passes through the second heat exchanger.

On the other hand, a plurality of reformers are connected in parallel, each of which receives the natural gas and steam supplied separately from the reforming fuel supply line to generate hydrogen gas to supply to the manifold.

According to one embodiment of the present invention, the reformer may be configured to generate a hydrogen gas by introducing a steam supplied separately from the natural gas supplied from the reforming fuel supply line by plasma reaction by an external power source.
In addition, a fuel supply method according to an embodiment of the present invention includes hydrogen gas and carbon monoxide from natural gas supplied from a reforming fuel supply line by receiving steam supplied separately in a reaction space maintaining a high temperature state. Mixing gas generating step of generating a mixed gas, carbon monoxide reduction step of reducing the concentration of carbon monoxide contained in the mixed gas and vaporized LNG supplied from the main fuel supply line and hydrogen gas generated in the reformer for the vessel It may include mixing and supplying to the engine.

In addition, a fuel supply method according to an embodiment of the present invention includes hydrogen gas and carbon monoxide from natural gas supplied from a reforming fuel supply line by receiving steam supplied separately in a reaction space maintaining a high temperature state. Mixing gas generating step of generating a mixed gas, carbon monoxide reduction step of reducing the concentration of carbon monoxide contained in the mixed gas and vaporized LNG supplied from the main fuel supply line and hydrogen gas generated in the reformer for the vessel It may include mixing and supplying to the engine.

According to the fuel supply apparatus and method of the marine engine according to the present invention has the following effects.

First, by directly obtaining hydrogen gas from the natural gas supplied from the LNG storage tank by the reformer and mixing it with LNG and supplying it to the engine, it is possible to widen the flammability limit of engine combustion and minimize the generation of nitrogen oxides as a result. .

In particular, by combusting the fuel of the LNG storage tank in the combustion burner to create a state of high temperature required for the reforming reaction, it is possible to minimize the additional configuration for the reforming reaction.

Second, a steam generator is provided in the reaction space to change the water into steam at a high temperature and use the generated steam for reforming reaction and water gas conversion for reducing carbon monoxide. Can be reduced.

In addition, heat exchange with the boil-off gas liquefaction line on the water supply line before passing through the steam generator to increase the temperature, it is possible to further reduce the energy required for steam generation.

Third, by distributing the flow rate by connecting a plurality of reformers in parallel, it is possible to overcome the capacity limitation of the hydrogen gas generated in the reformer itself, to produce a large amount of hydrogen gas required for the marine engine, and consequently hydrogen gas mixed with the main fuel. There is an advantage to increase the content of.

Fourth, the boil-off gas liquefaction line that is heat-exchanged with the main fuel supply line is provided, there is an advantage that can prevent excessive pressure rise due to the accumulation of boil-off gas in the LNG storage tank.

1 is a block diagram showing a fuel gas supply apparatus for a marine engine according to the prior art;
2 is a block diagram showing a fuel supply apparatus for a marine engine according to a first embodiment of the present invention;
3 is a view for explaining the principle of the reformer of FIG.
4 is a configuration diagram showing a fuel supply apparatus for a marine engine according to a second embodiment of the present invention;
5 is a configuration diagram showing a fuel supply apparatus for a marine engine according to a third embodiment of the present invention;
6 is a block diagram showing a fuel supply apparatus for a marine engine according to a fourth embodiment of the present invention; And
7 is a configuration diagram showing a fuel supply apparatus for a marine engine according to a fifth embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. In describing the present embodiment, the same designations and the same reference numerals are used for the same components, and further description thereof will be omitted.

First Embodiment

Referring to Figures 2 and 3, the configuration of the fuel supply apparatus according to the first embodiment of the present invention will be described.

The fuel supply device according to the present embodiment is composed of four supply lines, specifically, the main fuel supply line (L10), reforming fuel supply line (L20), boil-off gas liquefaction line (L30) and water supply line ( L40).

The main fuel supply line (L10) is a transfer line for extracting the LNG from the LNG storage tank 110 to supply to the marine engine 130, LNG by the pump 114 provided on the main fuel supply line (L10) It is configured to supply to the marine engine 130 side.

The main fuel supply line (L10) is a heat exchange with the boil-off gas liquefaction line (L30) to be described later while passing through the first heat exchanger (112) on the way. In this process, LNG in the main fuel supply line (L10) is supplied to the marine engine 130 in a vaporized state of the temperature rises.

The pump 114 of the main fuel supply line (L10) is provided in parallel with the flow rate control pressure control valve 116 to adjust the pressure of the fluid passing through.

In addition, a pressure sensor 118 is provided between each of the pressure control valves 116 and the lines connected to the pressure control valve 116, and according to the measured pressure of the flow control type pressure control valve 116. By adjusting the flow rate, an appropriate pressure can be maintained.

Although not shown in the figure, a heater for additional heating before supplying vaporized LNG heat-exchanged by the first heat exchanger 112 to the marine engine downstream of the first heat exchanger 112 in the main fuel supply line L10. May be provided.

The reforming fuel supply line L20 is a transport line which extracts gaseous natural gas from the LNG storage tank 110 and supplies it to a reformer 210 which will be described later. The natural gas supplied through the reforming fuel supply line L20 generates hydrogen gas while passing through the reformer 210.

In general, the reformer 210 is a device for generating hydrogen from fossil fuels, particularly in the fuel cell field.

In this embodiment, a steam reforming method is applied among various reforming methods, and the hydrogen gas is supplied from vaporized LNG supplied from the reforming fuel supply line (L20) by receiving steam supplied from the steam generator 218 to be described later. It is configured to generate.

To this end, the reformer 210 includes a reaction space 213, a combustion burner 212, a reforming reaction unit 211 and a carbon monoxide reducing unit (not shown).

The reformer 210 accommodates the reforming reaction unit 211 therein and has the reaction space 213 for maintaining a high temperature state.

In addition, the combustion burner 212 is provided in the reaction space 213, using the natural gas supplied from the LNG storage tank 110 as the combustion fuel, causing a combustion reaction with the outside air and the reaction space 213 ) The interior is heated to the temperature required for reforming.

In this embodiment, the branched from the reforming fuel supply line (L20) is configured to supply the natural gas required for the combustion of the combustion burner 212, but alternatively may be provided with a supply line for a separate combustion Do.

In general, since the reforming reaction occurs at about 500 ° C. or more, the natural gas maintains the inside of the reaction space 213 at a temperature necessary for the reforming reaction by combustion of the combustion burner 212.

The reforming reaction unit 211 is a mixed gas containing hydrogen gas and carbon monoxide from the natural gas supplied from the reforming fuel supply line (L20) by receiving steam supplied separately in a high temperature state in the reaction space (213) Generates.

Referring to FIG. 3, the reforming reaction unit 211 introduces natural gas and water vapor into the reactor body 20 containing the catalyst 40, and reacts with the chemical formula below to reform hydrogen and carbon monoxide.

 Then, the hydrogen gas decomposed by the reforming reaction is configured to be selectively separated by the hydrogen separation membrane 30 in the center. Here, the steam reforming catalyst 40 may be generally applied to nickel or ruthenium, and the hydrogen separation membrane 30 may be applied to palladium.

The carbon monoxide reduction unit is a component for minimizing carbon monoxide inevitably generated in the process of reforming in the reforming reaction unit 211.

In this embodiment, the carbon monoxide reduction unit is made in a manner by water gas shift.

For reference, the conversion of water gas is a reaction for converting carbon monoxide to hydrogen and carbon dioxide by adding water vapor, and the reaction formula may be expressed as follows.

When the reaction proceeds to produce carbon dioxide (CO ₂ ), it has the advantage of not only removing carbon monoxide (CO) but also producing additional hydrogen gas. In general, the water gas shift reaction is controlled by equilibrium, and the reaction composition is determined by temperature and pressure, and the direction of generating carbon dioxide is exothermic, which is more easily performed at low temperature. On the other hand, at high temperatures, an endothermic reaction, which is an endothermic reaction, consumes hydrogen to produce carbon monoxide.

In the present embodiment, the carbon monoxide reduction unit includes a high temperature conversion reaction unit 214 using a high temperature water gas conversion catalyst and a low temperature conversion reaction unit 215 using a low temperature water gas conversion catalyst.

In this embodiment, the high-temperature water-gas shift (HT WGS) reaction by the high temperature conversion reaction unit 214 and the low-temperature water gas conversion (Low-Temperature) by the low temperature conversion reaction unit 215 are performed. Water-Gas Shift: LT WGS) reduces the carbon monoxide concentration through two steps. In the high temperature conversion reaction unit 214, the carbon monoxide concentration of 10% or more is reduced to 5% or less using a Cr / Fe-based catalyst at around 500 ° C. The catalyst can be used to reduce the carbon monoxide concentration to about 0.5%.

In this embodiment, the carbon monoxide reduction unit is illustrated by the water gas conversion method, but alternatively, other types of carbon monoxide reduction methods such as selective oxidation, hydrogen separation membrane, and adsorptive separation can be applied.

The boil-off gas liquefaction line (L30) is a transfer line for removing the boil-off gas (BOG) generated from the upper portion of the LNG storage tank 110 to re-liquefy and re-introduced back into the LNG storage tank (110).

The boil-off gas liquefaction line (L30) is heat exchanged with the main fuel supply line (L10) while passing through the first heat exchanger (112) described above. In this process, the boil-off gas on the boil-off gas liquefaction line (L30) is liquefied by heat exchange with the LNG is re-introduced into the LNG storage tank (110).

In addition, the above-described second heat exchanger 122 is provided between the compressor 124 for the boil-off gas and the first heat exchanger 112 on the boil-off gas liquefaction line L30. Therefore, the boil-off gas is supplied to the first heat exchanger 112 in a state where the temperature is lowered while heat-exchanging with water on the water supply line L40.

On the other hand, on the boil-off gas liquefaction line (L30) is provided with a boil-off gas compressor 124 for compressing the boil-off gas extracted from the upper portion of the LNG storage tank (110). In addition, although not shown in the present embodiment, on the boil-off gas liquefaction line (L30) for additional cooling, a separate cooler may be provided downstream of the compressor (124) for boil-off gas.

On the other hand, the compressor 124 for the boil-off gas, the flow-controlled pressure control valve 116 is connected in parallel, between the pressure control valve 116 and the boil-off gas liquefaction line (L30) connected to the pressure control valve 116. The pressure sensor 118 is provided, and the appropriate pressure can be maintained by adjusting the flow volume of the flow regulating pressure regulating valve 116 according to the measured pressure.

In addition, downstream of the first heat exchanger 112 in the boil-off gas liquefaction line L30, an expansion type pressure regulating valve 116a is provided to control the pressure of the fluid passing therethrough.

The pressure sensor 118 is also connected between the boil-off gas liquefaction line L30 and the expansion pressure regulating valve 116a. The expansion-type pressure regulating valve 116a installed in the boil-off gas liquefaction line L30 downstream of the first heat exchanger 112 may pass the fluid passing through the pressure of the LNG storage tank 110 and the LNG in the LNG storage tank 110. It is an expansion valve that adjusts the pressure by expanding to correspond to the pressure of the head plus the pressure, the temperature of the LNG is lowered by the expansion.

In addition, the fuel supply apparatus of the present invention may include a boil-off gas reliquefaction apparatus. Even in this case, the present invention can liquefy the boil-off gas by heat exchange with the main fuel supply line (L10) by the boil-off gas liquefaction line (L30), it is possible to configure a small capacity of the boil-off gas reliquefaction apparatus installed separately.

In addition, the present embodiment is provided with a heat exchanger 112 for exchanging the boil-off gas liquefaction line (L30) and the main fuel supply line (L10), in contrast, a form provided with a recondenser for directly mixing LNG and boil-off gas It is also possible.

The water supply line L40 extracts water from the water tank 120 and supplies water to the steam generator 218. The water supply line L40 passes through a second heat exchanger 122 between the water tank 120 and the steam generator 218, and heat-exchanges with the boil-off gas liquefaction line L30 to be described later, in this process, the temperature of the water. Is supplied to the steam generator 218 in an elevated state.

The steam generator 218 serves to supply water to the reforming reaction unit 211 by changing the phase of water into a steam state by heat exchange in the reaction space 213 that maintains a high temperature state.

In the present embodiment, the steam generator 218 generates steam by using the water supplied from the water tank 120, but the reaction space after raising the temperature by the second heat exchanger 122 using sea water. (213) It is also possible to form the steam by flowing into the inside.

In addition, in this embodiment, the steam generated in the steam generator 218 is also supplied to each of the high temperature conversion reaction unit 214 and the low temperature conversion reaction unit 215 constituting the carbon monoxide reduction unit, so that one steam generator 218 is provided. It is possible to implement a more simplified structure by supplying all the steam required for the reaction of the reforming reaction unit 211 and the carbon monoxide reduction unit.

As described above, the gaseous LNG supplied from the main fuel supply line L10 and the hydrogen gas obtained through the reformer 210 are mixed in the manifold 310 and finally supplied to the marine engine 130.

By the fuel supply device as described above, by supplying the synthesis gas mixed with the main fuel and hydrogen gas to the engine, it is possible to increase the flammability limit of the combustion and, as a result, to minimize the generation of nitrogen oxides generated during the operation of the engine Will be.

Second Embodiment

Referring to Figure 4, the configuration of a fuel supply apparatus according to a second embodiment of the present invention will be described.

In this embodiment, the boil-off gas liquefaction line L30 passes through the first heat exchanger 112 and the expansion pressure regulating valve 116a and then downstream of the first heat exchanger 112 in the middle of the main fuel supply line L10. Is connected to. Accordingly, after the boil-off gas is heat-exchanged with LNG in the first heat exchanger 112, the expansion type pressure regulating valve 116 installed in the boil-off gas liquefaction line L30 passes through the first heat exchanger 112 to the main fuel supply line. It can be adjusted to correspond to the vaporized LNG pressure of (L10).

Although not shown in the drawing, downstream of the point where the main fuel supply line L10 is combined with the boil-off gas liquefaction line L30, a heater for additional heating may be provided before supplying the vaporized LNG to the marine engine.

Third Embodiment

Referring to Figure 5, the configuration of a fuel supply apparatus according to a third embodiment of the present invention will be described.

The present embodiment has the same basic configuration as the first embodiment described above, but includes a plurality of reformers 210 and 220 connected in parallel.

5 illustrates a form in which two reformers 210 and 220 are formed. In this way, by forming a plurality of reformers (210, 220) in parallel form, it is possible to distribute the flow rate to overcome the capacity limitation of the hydrogen gas generated in the reformers (210,220) can produce a larger amount of hydrogen gas.

In particular, since a large amount of hydrogen is required in the case of a ship, it is possible to increase the content of hydrogen gas mixed with the main fuel by connecting a plurality of reformers 210 and 220 in parallel.

As described above, the hydrogen gases generated from the plurality of reformers 210 and 220 connected in parallel are mixed with the main fuel in the manifold 320 and supplied to the marine engine.

Fourth Embodiment

Referring to Figure 6, the configuration of a fuel supply apparatus according to a fourth embodiment of the present invention will be described.

In the present embodiment, unlike the first embodiment described above, the steam supplied separately from the natural gas supplied from the LNG storage tank 110 is configured to generate hydrogen gas by plasma reaction by the external power source 250. do.

The plasma reformers 230 and 240 have an advantage of generating hydrogen without generating additional pollutants by using electrical energy from an external power source. In particular, low-temperature plasma can be easily obtained by electrically discharging organic vapors in a low pressure or normal pressure state and has a low power consumption.

The scheme of the plasma reforming reaction is shown below.

In the present embodiment, the reformers 230 and 240 may be applied to a Glidarc plasma reformer having a fan-shaped electrode for fast starting characteristics. And, unlike the first embodiment, the steam generator 238 is provided separately to the reformers 230 and 240, and consists of a form for supplying the steam generated through the reformers 230 and 240, respectively.

In addition, the present embodiment is configured such that the reforming fuel supply line (L20) is not directly connected to the LNG storage tank 110, but branched from the main fuel supply line (L10). That is, in this embodiment, the LNG supplied from the main fuel supply line (L10) is vaporized through the first heat exchanger (112), and then branched downstream of the first heat exchanger (112) so that a part of the steam generator is generated. 238 is supplied in the form.

On the other hand, the present embodiment also has a plurality of reformers 230 and 240 connected in parallel as in the third embodiment described above. Through this, it is possible to distribute the flow rate to overcome the capacity limitation of the hydrogen gas generated in the reformers 230, 240 itself to produce a larger amount of hydrogen gas.

Then, the generated hydrogen gas is mixed with the main fuel in the manifold 330 is supplied to the marine engine.

Although not shown in FIG. 6, in order to reduce the carbon monoxide generated in the reforming reaction of the reformers 230 and 240, for example, the high temperature conversion reaction unit 214 and the low temperature conversion reaction unit 215 are the reformers as in the first embodiment. It may be further provided on the downstream side (230,240).

The plasma generators of the reformers 230 and 240 may be configured such that, for example, three fan-shaped electrodes are positioned at 120 ° intervals inside the reactor.

Fifth Embodiment

Referring to Figure 7, the configuration of a fuel supply apparatus according to a fifth embodiment of the present invention will be described.

The basic configuration of this embodiment is similar to that of the fourth embodiment described above. However, in the present embodiment, after the boil-off gas liquefaction line L30 passes through the first heat exchanger 112 and the pressure control valve 116, the main fuel supply line L10 is downstream of the first heat exchanger 112. Connected. Accordingly, the boil-off gas is heat-exchanged with LNG in the first heat exchanger 112 and then merged into the main fuel supply line L10 to be used as fuel gas of a marine engine.

Therefore, the expanded pressure control valve 116a installed in the boil-off gas liquefaction line L30 downstream of the first heat exchanger 112 is vaporized LNG of the main fuel supply line L10 which has passed through the first heat exchanger 112. Adjust to correspond to the pressure.

It will be apparent to those skilled in the art that the present invention can be embodied in other specific forms without departing from the spirit or scope of the invention as defined in the appended claims. It is obvious to them. Therefore, the above-described embodiments should be regarded as illustrative rather than restrictive, and thus, the present invention is not limited to the above description and may be modified within the scope of the appended claims and their equivalents.

L10: main fuel supply line L20: reforming fuel supply line
L30: Evaporative gas supply line L40: Water supply line
110: LNG storage tank 112: the first heat exchanger
114: pump 116: pressure regulating valve
118: pressure sensor 120: water tank
122: second heat exchanger 124: compressor for boil-off gas
130: marine engine 210: reformer
211: reforming reaction unit 212: combustion burner
213: reaction space 214: high temperature conversion reaction unit
215: low temperature conversion reaction unit 218: steam generator
310: manifold

Claims (15)

A main fuel supply line which extracts LNG from the LNG storage tank and supplies the LNG to a marine engine;
A reforming fuel supply line for supplying natural gas from the LNG storage tank to a reformer;
A reforming reaction unit for receiving a separately supplied steam to generate a mixed gas containing hydrogen gas and carbon monoxide from the natural gas supplied from the reforming fuel supply line, the mixed gas generated from the reforming reaction unit is supplied and mixed A reformer including a carbon monoxide reduction unit for reducing the concentration of carbon monoxide contained in a gas and a reaction space accommodating the reforming reaction unit therein and maintaining a high temperature state; And
A manifold for mixing vaporized LNG supplied from the main fuel supply line and hydrogen gas generated from the reformer and supplying the mixed gas to the marine engine;
Fuel supply of the marine engine comprising a. The method of claim 1,
The reformer,
A fuel supply apparatus for a marine engine generating hydrogen gas through a reforming catalytic reaction by thermal energy. delete delete The method of claim 1,
It is provided inside the reaction space,
And a steam generator for changing the water supplied from the outside into steam by using a high temperature state inside the reaction space. The method of claim 1,
The reformer,
And a combustion burner supplying heat into the reaction space by a combustion reaction by natural gas supplied from the LNG storage tank and air supplied from the outside. The method of claim 1,
The carbon monoxide reduction unit,
A fuel supply apparatus for a marine engine including any one or more of a high temperature conversion reaction unit using a high temperature water gas conversion catalyst and a low temperature conversion reaction unit using a low temperature water gas conversion catalyst. The method of claim 7, wherein
It is provided inside the reaction space,
A steam generator which phase-changes water supplied from the outside into steam by using a high temperature state inside the reaction space;
Steam generated from the steam generator is supplied to each of the high temperature conversion reaction unit and the low temperature conversion reaction unit fuel supply apparatus for a marine engine. The method of claim 1,
A first heat exchanger is provided during the main fuel supply line;
And a boil-off gas liquefaction line which extracts boil-off gas from the upper portion of the LNG storage tank, passes through the first heat exchanger, and is connected to the LNG storage tank again. The method of claim 1,
A first heat exchanger is provided during the main fuel supply line;
And a boil-off gas liquefaction line which extracts boil-off gas from the upper portion of the LNG storage tank, passes the first heat exchanger, and is connected downstream of the first heat exchanger of the main fuel supply line. 11. The method according to claim 9 or 10,
The boil-off engine fuel supply device, characterized in that the boil-off gas liquefied line compressor is installed. 12. The method of claim 11,
A second heat exchanger is provided downstream of the compressor for the boil-off gas in the boil-off gas liquefaction line;
Downstream of the compressor for boil-off gas, water supplied from the outside is
A fuel supply device for a marine engine, characterized by passing through a second heat exchanger. The method of claim 1,
A plurality of reformers are connected in parallel, each of which receives the natural gas supplied from the reforming fuel supply line and the steam supplied separately to generate hydrogen gas and supply the hydrogen gas to the manifold. Feeder. The method of claim 1,
The reformer,
The fuel supply apparatus for a marine engine, characterized in that the steam supplied separately from the natural gas supplied from the reforming fuel supply line to generate a hydrogen gas by plasma reaction by an external power source. A mixed gas generating step of generating a mixed gas including hydrogen gas and carbon monoxide from natural gas supplied from a reforming fuel supply line by receiving steam supplied separately in a reaction space maintaining a high temperature state;
A carbon monoxide reduction step of reducing the concentration of carbon monoxide contained in the mixed gas; And
Mixing and supplying vaporized LNG supplied from the main fuel supply line and hydrogen gas generated from the reformer to a marine engine;
To perform, the fuel supply method of the engine for ships.

Images