KR20220145714A - Fuel cell and vessel comprising the same - Google Patents

Abstract

A fuel cell system for a vessel according to the present invention includes: a front end fuel cell that generates electricity by receiving fuel and air containing hydrogen; and a rear end fuel cell that generates electricity by receiving fuel and air discharged from the front end fuel cell, wherein the fuel cell system supplies electricity produced using the front end fuel cell and the rear end fuel cell to customers in the vessel while the vessel is in operation, and electricity generated using the rear end fuel cell is supplied to customers in the vessel while the vessel is anchored in a port. An objective of the present invention is to provide a cascade fuel cell system with improved power generation efficiency compared to a conventional single fuel cell and a vessel including the same.

Description

Fuel cell and vessel comprising the same

The present invention relates to a fuel cell and a ship including the same.

In general, ships use diesel engines to generate driving power using diesel oil, gas engines to generate driving power using gas such as LNG, and dual fuel engines to generate driving power by mixing diesel oil and gas. is promoted using

Recently, as the demand for eco-friendly/high-efficiency engines increases due to the strengthening of IMO environmental regulations, research on propulsion systems using various fuels is being actively conducted. In particular, technologies that can be promoted while reducing the emission of environmental pollutants such as sulfur oxides (SOx) and nitrogen oxides (NOx) emitted from ships are being studied.

Ships according to the prior art have installed environmental pollutant reduction devices such as scrubbers and SCRs in order to reduce the emission of environmental pollutants such as sulfur oxides (SOx) and nitrogen oxides (NOx). However, there is a problem in that ships according to the prior art cannot satisfy the environmental regulations only with the environmental pollutant reduction device as the environmental regulations are gradually strengthened. As environmental regulations are strengthened, the processing capacity of the environmental pollutant reduction device should be increased, because the processing capacity is proportional to the size of the reduction device.

In a ship with limited space, if the proportion of environmental pollutant reduction devices increases, it is inefficient because not only the space for loading cargo or people is relatively reduced, but also fuel economy increases due to the weight of the reduction device. Therefore, the development of environmentally friendly and highly efficient ships is urgently needed, and the introduction of fuel cells is being studied to reduce environmental pollution compared to existing fuels. In particular, a solid oxide fuel cell (SOFC), as one of these fuel cells, has a wide selection of fuel and electrolyte and has the advantage of exhibiting excellent operating efficiency. However, since the solid oxide fuel cell operates at a high temperature ranging from 500 to 1,000° C., there is a problem in that it takes a lot of time for initial operation and re-operation after a pause.

The present invention was created to solve the problems of the prior art as described above, and an object of the present invention is to provide a cascade fuel cell system in which power generation efficiency is improved compared to a conventional single fuel cell, and a ship including the same.

Another object of the present invention is to provide a fuel cell system capable of reducing fuel consumption by using some or all of the fuel cell to produce and supply electric power according to the operating state of the ship, and to provide a ship including the same.

A fuel cell system for a ship according to an aspect of the present invention provides a front-end fuel cell for generating electricity by receiving fuel and air containing hydrogen, and a rear-end for producing electricity by receiving fuel and air discharged from the front-end fuel cell. and a fuel cell, wherein the fuel cell system supplies electricity produced by using the front-end fuel cell and the rear-end fuel cell to a consumer in the ship while the ship is operating, and while the ship is anchored in a port The electricity produced by using the rear-end fuel cell is supplied to the demand in the ship.

Specifically, the front end fuel cell may include a burner that burns supplied fuel, and the burner may not operate while the ship is operating.

Specifically, the burner may burn at least a portion of fuel while the ship is anchored in a port to maintain the temperature inside the fuel cell at the front stage above a predetermined temperature.

Specifically, the front-end fuel cell and the rear-end fuel cell are sequentially provided on an anode supply line for supplying fuel containing hydrogen and a cathode supply line for supplying air, and the cathode supply line includes the front-end fuel cell. It may include a branch line that branches upstream of the cell and joins between the front end fuel cell and the rear end fuel cell.

Specifically, the front-end fuel cell and the rear-end fuel cell are provided in plurality, and the rear-stage fuel cell has a power generation capacity smaller than that of the front-end fuel cell, and the plurality of rear-end fuel cells are provided while the ship is anchored in the harbor. It may be to supply the required amount of power demand.

The fuel cell system according to the present invention sequentially provides a front-end fuel cell and a rear-end fuel cell, and has superior power generation efficiency compared to a single fuel cell having the same capacity as the sum of their power generation capacities, and is used to secure internal temperature necessary for operation. The time required can be shortened.

In addition, in the fuel cell system according to the present invention, when a ship is anchored in a port, only a part of the fuel cell of the fuel cell system is operated to meet the power demand, but the fuel cell that is not in operation maintains the internal temperature and the time required for re-operation can be shortened

1 is a conceptual diagram illustrating a conventional fuel cell system.
2 is a conceptual diagram illustrating a fuel cell system according to an embodiment of the present invention.

The objects, specific advantages and novel features of the present invention will become more apparent from the following detailed description and preferred embodiments taken in conjunction with the accompanying drawings. In the present specification, in adding reference numbers to the components of each drawing, it should be noted that only the same components are given the same number as possible even though they are indicated on different drawings. In addition, in describing the present invention, if it is determined that a detailed description of a related known technology may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be omitted.

Hereinafter, it should be noted that high pressure, low pressure, high temperature, low temperature, high load, low load, and flow rate are relative and do not represent absolute values.

Hereinafter, the fuel for supplying the fuel cell may be hydrogen, and a compound containing hydrogen atoms, such as a hydrocarbon containing hydrogen such as natural gas, coal gas, petroleum gas, ethane, ethanol, methanol, or a mixture or ammonia, etc. can mean encompassing Furthermore, steam used for reforming a compound containing hydrogen to produce hydrogen gas is also referred to as fuel.

Hereinafter, the above-described fuel and air to be supplied to the fuel cell may be referred to as a fluid.

Hereinafter, a fuel cell refers to a high-efficiency clean power generation system that directly converts hydrogen contained in the fuel and oxygen in the air into electric energy through an electrochemical reaction. That is, the fuel cell may be to generate electricity using fuel containing hydrogen. Fuel cells may be classified according to the type of electrolyte used. The fuel cell exemplified in the present invention generates power at a high temperature of 500 to 1000° C., and is a solid oxide (SOFC) fuel cell or molten carbonate. It may be a fuel cell (MCFC, Molten Carbonate Fuel Cell), but is not limited thereto.

Hereinafter, it is noted that a vessel is an expression that encompasses not only a shipping container ship, a commercial vessel, a vessel capable of producing natural gas in the ocean, but also an offshore structure including a gas platform and an offshore float.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a conceptual diagram illustrating a conventional fuel cell system.

Referring to FIG. 1 , a conventional fuel cell system 1 includes a plurality of fuel cells 10 , an anode supply line L1 , a cathode supply line L2 , and the like.

The fuel cell 10 may include a fuel cell stack including a fuel electrode, an electrolyte, and an air electrode therein, and a fuel cell stack in which a sealing material, a connecting material, and the like are repeatedly stacked. Although not shown, the fuel cell 10 communicates with the fuel supplied through the anode supply line L1, which will be described later, the air supplied through the cathode supply line L2, and the gas discharged from the fuel cell 10. It may further include a flow path and a wire for transmitting electricity generated by the fuel cell 10 to the outside of the fuel cell system 1 .

The fuel cell 10 may generate electricity using hydrogen or a fuel containing hydrogen and oxygen in the air, and may discharge fuel and air that have reacted or have not reacted from the fuel cell stack. The fuel cell 10 may further include a burner (not shown) for burning unreacted fuel discharged from the fuel cell stack. The burner may burn the unreacted fuel to discharge exhaust gas to the outside of the fuel cell system 1 .

The anode supply line L1 may supply fuel including hydrogen from the outside of the fuel cell system 1 to the fuel cell 10 . The anode supply line L1 may be connected to the inside of the fuel cell 10 to supply hydrogen or a fuel including hydrogen to the anode of the fuel cell 10 . The cathode supply line L2 may supply air from the outside of the fuel cell system 1 to the fuel cell 10 . The cathode supply line L2 may be connected to the inside of the fuel cell 10 to supply air to the cathode of the fuel cell 10 .

In the conventional fuel cell system 1, a plurality of fuel cells 10 may be provided in parallel. The fuel cell 10 is provided in plurality, such as the first fuel cell 10a to the n-th fuel cell 10n, and the plurality of fuel cells 10 includes an anode supply line L1 and a cathode supply line L2. may be connected in parallel to each other. When the plurality of fuel cells 10 are configured in parallel, there is an advantage in that the power generation capacity of the entire fuel cell system 1 can be easily controlled compared to when the plurality of fuel cells 10 are configured in series.

2 is a conceptual diagram illustrating a fuel cell system according to an embodiment of the present invention.

Referring to FIG. 2 , the marine fuel cell system 2 includes a plurality of front end fuel cells 100 , a plurality of rear end fuel cells 110 , an anode supply line L10 , a cathode supply line L20 , and the like. Hereinafter, differences in the fuel cell system 2 according to the present embodiment compared to the conventional fuel cell system 1 will be mainly described, and descriptions of the same content will be omitted.

The fuel cell system 2 includes a front-end fuel cell 100 and a rear-end fuel cell 110 sequentially provided based on the flow of fuel and air. That is, the front end fuel cell 100 receives fuel containing hydrogen from the anode supply line L10 and air from the cathode supply line L20 to produce electricity, and the rear end fuel cell 110 is a front end fuel cell It is to produce electricity by receiving fuel and air discharged from (100).

The fuel cell system 2 of the present embodiment is provided inside the ship to satisfy the power demand required by the demand in the ship. Preferably, the vessel may be propelled using electricity produced by the fuel cell system 2 . The fuel cell system 2 generates electricity in a different way according to the sailing state of the vessel, and thus it is possible to supply electricity according to the different electric power demand according to the sailing state. Specifically, the sailing state of the vessel may be divided into a case of large operation and a case of anchoring in a port, and the power demand of the vessel may be greater when operating. The fuel cell system 2 generates electricity using both the front-end fuel cell 100 and the rear-end fuel cell 110 while the ship is operating and supplies it to the demand in the ship. (110) can be used to produce electricity and supply it to the demand in the ship.

In the fuel cell system 2 , the front end fuel cell 100 and the rear end fuel cell 110 may be provided in plurality. A plurality of front end fuel cells 100 may be provided in parallel like the first front end fuel cells 100a to nth front end fuel cells 100n, and the first rear end fuel cells 110a to nth rear end fuel cells ( 110n), a plurality of rear-stage fuel cells 110 may be provided. The front end fuel cell 100 and the rear end fuel cell 110 may be connected in parallel to the anode supply line L10 and the cathode supply line L20, respectively.

The front end fuel cell 100 and the rear end fuel cell 110 are provided on the anode supply line L10 and the cathode supply line L20 , and are connected between the front end fuel cell 100 and the rear end fuel cell 110 . This line may be referred to as a front-end anode discharge line L11 and a front-end cathode discharge line L21. The cathode supply line L20 may further include a branch line L22 that branches upstream of the front-end fuel cell 100 based on the flow of air and joins between the front-end fuel cell 100 and the rear-end fuel cell 110 . can That is, the branch line L22 may branch from the air supply line L20 upstream of the front end fuel cell 100 and be connected to the front end cathode discharge line L21. The branch line L22 supplies air to the rear-stage fuel cell 110 to increase the fraction of unreacted air in the air supplied to the rear-stage fuel cell 110 to increase the efficiency of electricity production in the rear-stage fuel cell 110 . have. Alternatively, the branch line L22 increases the flow rate of air supplied to the rear-stage fuel cell 110 when the temperature of the rear-stage fuel cell 110 is higher than a predetermined temperature to lower the internal temperature of the rear-stage fuel cell 110 . can

For example, the first front end fuel cell 100a receives fuel and air from the anode supply line L10 and the cathode supply line L20 to produce electricity, and the anode exhaust gas including the unreacted fuel is the front end anode supply line. The cathode exhaust gas is supplied to the first rear-stage fuel cell 110a through the discharge line L11, and the cathode exhaust gas including unreacted air can be supplied to the first rear-stage fuel cell 110a through the front-end cathode discharge line L21. However, the present invention is not limited thereto. Although not shown, a plurality of rear-end fuel cells 110 may be connected to one front-end fuel cell 100 .

Each of the front end fuel cell 100 and the rear end fuel cell 110 may include a burner (not shown) for burning the supplied fuel. Preferably, the front end fuel cell 100 includes a burner, but the rear end fuel cell 110 may not include a burner. The burner may burn at least a portion of fuel discharged without reacting inside each fuel cell. Among them, whether or not the burner of the front end fuel cell 100 operates may vary depending on the operating state of the vessel.

Specifically, the burner of the front end fuel cell 100 may not operate while the ship is operating. When the ship operates, fuel that does not react in the process of generating electricity from the front end fuel cell 100 may be supplied to the rear end fuel cell 110 through the front end anode discharge line L11, and the non-reactive air is supplied to the rear-stage fuel cell 110 through the front-stage cathode discharge line L21 and may be used for an electrochemical reaction in the rear-stage fuel cell 110 .

Specifically, the burner of the front end fuel cell 100 may be used to burn at least a portion of fuel while the ship is anchored in a port to maintain the temperature inside the front end fuel cell 100 above a predetermined temperature. The predetermined temperature may be, for example, 500° C. or higher. When a ship is anchored in a port, the front end fuel cell 100 is not operated and only the rear end fuel cell 110 is operated to meet the power demand of the ship, but the front end fuel cell 100 uses a burner to When the previous stage fuel cell 100 is re-operated by maintaining the internal temperature above a predetermined temperature, it is possible to significantly reduce the time required for operation preparation.

1 and 2 , an operation method in the case of configuring the fuel cell system 2 as in the present embodiment will be described in more detail.

According to this embodiment, a plurality of fuel cells are sequentially connected, and the fuel cell system 2 that generates additional electricity using exhaust gas of a preceding fuel cell is referred to as a cascade system. Even when the cascade type fuel cell system 2 is provided to have the same power generation capacity as the conventional fuel cell system 1 in theory, in practice, it may exhibit higher power generation efficiency than the conventional fuel cell system 1 .

For example, in FIG. 1 , the fuel cell 10a has a power generation capacity of 100 kW, and in FIG. 2 , the power generation capacity of the front end fuel cell 100 a is 90 kW and the power generation capacity of the rear end fuel cell 110 a is 10 kW. The generating capacity may be equal to each other. However, there is a limit to the amount of fuel and air flowing through the flow passage inside the fuel cell in contact with each electrode of the fuel cell, and it is difficult to uniformly mix fuel and air in a relatively narrow flow passage. Since it becomes difficult to contact the electrode, the actual power generation capacity of the cascade fuel cell system 2 in which unreacted fuel and air are drawn out from the front-stage fuel cell and re-injected into the rear-stage fuel cell is equal to the conventional fuel of the same capacity. It may appear larger than the battery system (1).

In addition, the fuel cell system 2 can implement a power supply method suitable for the sailing state of the ship and implement a quick response according to the change of the sailing state, especially when the ship is anchored in a port, an energy-efficient system operation method. can provide Specifically, the rear-end fuel cell 110 of the fuel cell system 2 may have a smaller power generation capacity than the front-end fuel cell 100 , but only the plurality of rear-end fuel cells 110 , the power required while the vessel is anchored in the port. It could be supply and demand.

For example, a vessel may require 20 MW of power while in operation and only 2 MW of power while moored in port. The conventional fuel cell system 1 as shown in FIG. 1 generates electricity by configuring 200 fuel cells 10 with the same power generation capacity of 100 kW in parallel. The fuel cell system 1 operates all 200 fuel cells 10 while the ship is operating to supply 20MW of power, and operates only 20 fuel cells 10 while the ship is anchored in a port, and operates 180 stopped the operation and supplied 2MW of power.

In contrast, in the fuel cell system 2 according to the present embodiment, 200 each of the front end fuel cell 100 and the 10kW rear fuel cell 110 having a power generation capacity of 90 kW may be provided to produce electricity. The fuel cell system 2 supplies 20MW of power by operating 200 each of the front-end fuel cells 100 and the rear-end fuel cells 110 while the ship is operating, and while the ship is anchored in the port, the front-end fuel cell 100 ) stops the operation and operates 200 rear-stage fuel cells 110 to supply 2MW of power.

When a ship is anchored in a port, the fuel cell maintains its operation in a stopped state, but in case of subsequent operation, the temperature inside the fuel cell can be constantly maintained above a predetermined temperature, and this operation is performed in a hot standby mode. It can be referred to as hot standby). When 180 fuel cells 10 are maintained in the hot standby state in the fuel cell system 1, more fuel is consumed because the inside of the fuel cell 10 having a relatively large volume must be heated, and the fuel cell 10 Gas and unreacted fuel used for internal heating had to be discharged to the outside of the fuel cell 10 and treated.

In contrast, in the fuel cell system 2 , the inside of the fuel cell 100 is heated at the front end by using the burner of the fuel cell 100 at the front end and the discharged gas is discharged from the anode discharge line L11 and the cathode discharge line L21 at the front end. It can be supplied to the rear-stage fuel cell 110 through the bar, the rear-stage fuel cell 110 can use the waste heat that is used for heating the front-stage fuel cell 100 and discharged, thereby enabling energy-efficient power generation. The rear-end fuel cell 110 receives the exhaust gas from the front-end fuel cell 100 in a heated state through the front-end anode discharge line L11 and the front-end cathode discharge line L21, so it is easy to maintain the temperature required for electricity production, A bar burner capable of generating electricity using unreacted fuel discharged from the previous stage fuel cell 100 may be omitted.

The fuel cell system 2 as described above can increase power generation efficiency compared to a case where a plurality of fuel cells are arranged in a cascade form and a plurality of fuel cells are simply connected in parallel. In addition, the fuel cell system 2 is provided so that the front end fuel cell 100 of a relatively small volume compared to the fuel cell 10 of the conventional fuel cell system 1 can be maintained in a hot standby state when the vessel is anchored, so that the entire system At the same time, as the power demand increases due to the operation of the vessel again, the fuel cell 100 can be operated immediately at the front end, thereby enabling rapid response to changes in the vessel's sailing state.

It goes without saying that the present invention is not limited to the above-described embodiments, and a combination of the embodiments or a combination of at least one of the embodiments and a known technology may be included as another embodiment.

In the above, the present invention has been described focusing on the embodiments of the present invention, but this is only an example and does not limit the present invention. It will be appreciated that various combinations or modifications and applications not illustrated in the embodiments are possible within the scope. Accordingly, descriptions related to variations and applications that can be easily derived from the embodiments of the present invention should be interpreted as being included in the present invention.

1: Conventional fuel cell system 10: Fuel cell
L1: anode supply line L2: cathode supply line
2: fuel cell system 100: front end fuel cell
110: rear end fuel cell L10: anode supply line
L11: front end anode discharge line L20: cathode supply line
L21: front cathode discharge line L22: branch line

Claims (5)

A fuel cell system for ships, comprising:
A front-end fuel cell for generating electricity by receiving fuel and air containing hydrogen; and
and a rear-stage fuel cell that generates electricity by receiving fuel and air discharged from the front-stage fuel cell,
The fuel cell system,
While the ship is operating, electricity produced by using the front-end fuel cell and the rear-end fuel cell is supplied to the demand in the ship, and while the ship is anchored in the port, electricity produced using the rear-end fuel cell is used as the A fuel cell system for ships, which is supplied to a demand within a ship. The method of claim 1,
The front end fuel cell is
a burner for burning the supplied fuel;
The burner is
A fuel cell system for a ship that does not operate while the ship is in operation. 3. The method of claim 2,
The burner is
By burning at least a portion of fuel while the ship is anchored in a port, the fuel cell system for a ship is to maintain the temperature inside the front end fuel cell above a predetermined temperature. The method of claim 1,
The front end fuel cell and the rear end fuel cell are
It is sequentially provided on the anode supply line for supplying fuel containing hydrogen and the cathode supply line for supplying air,
The cathode supply line is
and a branch line branching upstream of the front end fuel cell and joining between the front end fuel cell and the rear end fuel cell. The method of claim 1,
The front end fuel cell and the rear end fuel cell are provided in plurality,
The rear stage fuel cell,
The power generation capacity is smaller than that of the front-end fuel cell, the plurality of rear-end fuel cells will supply the amount of power required while the ship is anchored in a port, the marine fuel cell system.

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