KR20230156369A - Apparatus and method for burning purge gas - Google Patents

Abstract

An apparatus (100) and method for combusting purge gas generated from an ammonia fuel system (108) that supplies fuel to an ammonia fueled engine (112), wherein the apparatus (100) is a boiler system (102) comprising a burner. (104), a fuel inlet (111) configured to supply fuel to sustain an auxiliary flame within the burner (104), and a fuel inlet (111) configured to intermittently receive purge gas from the ammonia-fueled engine (112) and deliver the purge gas to the burner (104). A boiler system (102) comprising a purge gas inlet (121) configured to supply a purge gas inlet (121), wherein the purge gas comprises a mixture of ammonia and an inert gas, the burner (104) comprising an auxiliary It is configured to burn ammonia with a flame.

Description

Apparatus and method for burning purge gas

The present invention relates to an apparatus and method for combusting purge gas from an ammonia fuel system that fuels an ammonia fueled engine.

Marine engines powered by oil or gas are well known in the art. Oil and gas fired boilers for marine steam production are also well known in the art. Typically, the selection of fuel for boiler operation is made in relation to the fuel selected for marine engine operation. Accordingly, when marine engines are driven by oil, boilers are often driven by oil as well. However, marine engines and boilers may run on different fuels.

One drawback of most marine engines today is the marine air pollutants, particularly carbon dioxide (CO ₂ ), emitted from marine engines when providing propulsion. Considering environmental aspects, it is generally agreed that not only _CO2 emissions but also other greenhouse gas emissions should be reduced. As a solution, alternative fuels are gaining traction in the marine industry. These include fuels such as methanol, hydrogen, ammonia or biomaterial conversions. However, introducing alternative fuels may lead to other problems, for example other environmental issues. For example, by using some of the alternative fuels to power marine engines, the gases from these fuels may not be vented directly to the atmosphere, for example because of their toxicity, and often before being vented to the atmosphere. It needs to be removed. This latter case is the case, for example, when using ammonia as fuel. Therefore, alternative fuels may be more environmentally friendly than conventional fuels in terms of greenhouse gas emissions, but there are still other problems that need to be overcome.

In an attempt to address some of this problem, document CN109140496 discloses a boiler ignition device using ammonia purge gas as a heat source comprising a purge gas supply pipeline and an ignition gas supply pipeline.

However, as explained below, the prior art provides a more environmentally friendly marine solution that allows for the use of alternative fuels while also addressing a set of design criteria that ensures that noxious gases are released into the atmosphere or are released in limited quantities. The prior art does not disclose a device, and in particular the prior art does not disclose how to provide an overall device that can be used in a convenient manner over time when meeting the above set of design criteria.

The object of the present invention is to provide a more environmentally friendly marine device that allows the use of alternative fuels and at the same time addresses a set of design criteria that ensures that toxic gases are not released into the atmosphere or are released in limited quantities.

This object is achieved by means of an apparatus for combustion of purge gases arising from an ammonia fuel system supplying fuel to an ammonia fueled engine, the apparatus comprising:

As a boiler system,

burner,

a fuel inlet configured to supply fuel to sustain an auxiliary flame within the burner; and

a boiler system comprising a purge gas inlet configured to intermittently receive purge gas from an ammonia fuel system and supply purge gas to a burner, wherein the purge gas includes a mixture of ammonia and an inert gas;

The burner is configured to burn ammonia with an auxiliary flame.

Preferably, the ammonia-fueled engine is a marine engine. Ammonia-fueled engines are advantageous because they use a more environmentally friendly fuel, ammonia, compared to most fossil fuels used today, such as oil and gas, to power engines. This device is advantageous because it combusts the purge gas from the ammonia fuel system instead of venting it to the atmosphere. Purge gases may be generated when an ammonia-fueled engine switches fuel from ammonia to another fuel or when an ammonia-fueled engine is shut down in a controlled manner or as a result of an emergency situation. At this stage, the purge gas is toxic and should not be vented to the atmosphere. Instead, the purge gas inlet receives purge gas from the ammonia fuel system and supplies this purge gas to the burner. By burning the mixture in a burner, the purge gas is not released into the atmosphere as a toxic gas, but instead as a combustion gas composed primarily of nitrogen and water. Therefore, it can be said that this device acts as a safety mechanism by burning purge gas within the burner instead of discharging toxic gas into the atmosphere. Thus, a more environmentally friendly marine device is achieved, which uses an alternative fuel, namely ammonia, while at the same time no or as little as possible toxic gases are emitted into the atmosphere.

Preferably, ammonia-fueled engines operate on ammonia in pure form. However, it should be noted that ammonia may contain small amounts of water. It is also important to note that ammonia can be mixed with other fuels, such as alcohols such as methanol or ethanol, or gases such as hydrogen. In cases where ammonia is too difficult to combust with an auxiliary flame, it may be advantageous to blend ammonia with other fuels.

The purge gas may include a mixture of ammonia and an inert gas. The inert gas may be nitrogen. Preferably, the nitrogen is compressed nitrogen. However, it should be noted that other inert gases may also be used. It should be noted that if ammonia is mixed with other fuels, the purge gas will also contain other fuels. Fuel may initially be supplied to provide a pilot flame or as main fuel when the burner is run in operating mode. When fuel is supplied to provide a pilot flame, the fuel may be in small quantities to provide a small flame for ignition of the main fuel. The pilot flame may be intended to ignite the fuel supplied as the main fuel. When fuel is supplied as the main fuel, the fuel is supplied in larger quantities compared to the fuel supplied to provide the pilot flame. Preferably, when burning ammonia, the main fuel acts as an auxiliary flame such that the purge gas is combusted by the auxiliary flame. The auxiliary flame must be of a certain size to ensure complete combustion of ammonia.

Preferably, when the boiler is operated to burn the purge gas, the boiler provides supplemental fuel at a rate of 15-50%, preferably 25-50%, compared to the rate at which fuel is provided when the boiler is operating at full operation. It can be operated at 15-50%, preferably 25-50%, of full operation, meaning that the flame can be sustained even when the burner is operating for purge gas combustion and not operating at full operation for heat production. It can be ensured that the ammonia supplied to the burner is burned. In this regard, it should be noted that heat production may refer to steam production, hot water heating, thermal fluid heating, or heating of any other medium used in a boiler. Because purge gases are typically more difficult to ignite than the main fuel, the auxiliary flame typically must be larger than the pilot flame. The fuel inlet and purge gas inlet may be separate inlets. However, as discussed further below, if the purge gas includes both a gas and a liquid, the liquid may be supplied to the burner by the fuel inlet and the gas may be supplied to the burner by the purge gas inlet.

Burners may be steam atomized or pressure atomized. It should be noted that if the burner is a vapor atomizing type, fuel may be supplied to provide pilot fuel for igniting the main fuel. If the burner is of the pressure atomizing type, fuel is usually supplied only as the main fuel. Instead, pressure atomizing burners include a spark igniter configured to ignite the primary fuel. However, if the burner is a vapor atomizing type, fuel may be supplied to provide a pilot flame as a spark igniter to ignite the main fuel.

The boiler system may be configured to operate in at least one of a first mode and a second mode,

The first mode is a heat production mode in which heat is produced,

The second mode is an ammonia safety purge mode where the boiler is kept warm and ready for high speed operation and/or the pilot flame is maintained.

The first mode may be the mode of operation discussed above. The second mode may be a preparation mode in which the boiler prepares for high-speed operation or high-speed start-up. In the first mode and the second mode, the burner may be an active burner. The term “active burner” herein refers to a burner that is ready to receive purge gas through the purge gas inlet at any time, since shutdown of the engine may occur at any time. If the burner is an active burner, the burner is in an operating mode or in a ready mode ready to receive purge gas.

The disclosed boiler system allows a more flexible boiler system to be achieved. By having a more flexible boiler system, the boiler system can be used in more ways than just for heat production, which is the main purpose of the burner. Accordingly, the boiler system may be configured to also burn the purge gas. Switching between the different modes provides that conventional burners, for example oil-fired burners or gas-fired burners, can be used not only for heat production but also for purge gas combustion. However, it should be noted that the burner may be configured to operate in more than one mode.

The boiler system may be configured to operate in one of at least a first sub-mode and a second sub-mode of the first mode, wherein the main flame is sustained within the burner for heat production and a purge gas is supplied to the burner. is not supplied to the burner, and in the second sub-mode the main flame continues within the burner for heat production, a purge gas is supplied to the burner and ammonia is burned by the main flame acting as an auxiliary flame.

A first sub-mode of the first mode may be configured to produce heat from the main fuel. The second sub-mode of the first mode may be configured to produce heat from the main fuel and purge gas to combust the purge gas.

The boiler system ignites the auxiliary flame by first igniting the pilot flame and then igniting the auxiliary flame from the pilot flame, or, if the pilot flame persists, igniting the auxiliary flame directly from the pilot flame and supplying purge gas to the burner to ignite the ammonia. It may be configured to burn with a flame.

Preferably, each inlet can be controlled by one or more valves. One or more valves may be configured to open and close the fuel inlet and the purge gas inlet to enable switching between at least two modes and/or between a first sub-mode and a second sub-mode of the first mode. One or more valves may be configured to independently open and close the fuel inlet and independently open and close the purge gas inlet.

The fuel inlet may be connected via a fuel supply line to a fuel source, which may be configured to supply a fuel selected from the group consisting of liquefied natural gas (LNG), distillate and residual fuel. This may include, for example, diesel, marine diesel fuel (MGO), low sulfur fuel oil (VLSFO) and heavy fuel oil (HFO). The fuel may be biofuel. It should be noted that other forms of fuel such as ammonia, hydrogen and methanol can also be used as fuel. It should be noted that fuel may contain two types of fuel. The two types of fuel may be premixed together and supplied from the same fuel source, or may be kept separate and supplied from two different fuel sources. The fuel source may be a tank, for example. If the fuel contains two types of fuel supplied from two different fuel sources, these fuel sources may each have one supply line from each fuel tank to the burner, but may also share. If the two types of fuel are supplied from two different fuel sources each with a supply line, they may each have a fuel inlet, or alternatively the fuel from the two different fuel sources is introduced to the burner through a common inlet. There is one fuel inlet connected to two different supply lines so that Other fuel sources may be configured to supply fuel selected from the group consisting of liquefied natural gas (LNG), distillates, and residual fuels. This may include, for example, diesel, marine diesel fuel (MGO), low sulfur fuel oil (VLSFO) and heavy fuel oil (HFO). The fuel may be biofuel. It should be noted that other forms of fuel such as ammonia, hydrogen and methanol may also be used as fuel.

The device may further include an ammonia fuel system, the ammonia fuel system comprising:

Ammonia fuel source for storing ammonia,

fuel supply system,

an ammonia-fueled engine, and

A purge source containing an inert gas, comprising a purge source configured to expel ammonia from components of the ammonia fuel system to the purge gas inlet by flushing the inert gas through the components of the ammonia fuel system.

This is advantageous as it ensures that no unnecessary fuel is present within the pipeline of an ammonia fuel system. Therefore, as described above, when an ammonia-fueled engine switches fuel or is shut down, ammonia may be present in the pipeline, which should not be vented to the atmosphere or returned to the ammonia fuel source. By flushing inert gas through these parts of the ammonia fuel system, any ammonia that may remain in the pipeline can be forced out of the ammonia fuel system to form a mixture of ammonia and inert gas, which can then be directed to the boiler system. The mixture may be transferred via an evaporator and/or separator, taking into account that the mixture of, for example, ammonia and the inert gas may be a mixture of gaseous and liquid phases. Forcing the ammonia out of the ammonia fuel system by means of an inert gas causes almost all of the ammonia to escape from the ammonia fuel system. This results in a safer and more environmentally friendly device.

Ammonia can be expelled from components of an ammonia fuel system. Preferably, ammonia can be expelled from parts close to the engine, since these parts may contain dirty ammonia and mixing of dirty ammonia back into the ammonia fuel source should be prevented.

Preferably, ammonia forced out of the ammonia fuel system should not be able to migrate to other parts of the ammonia fuel system and should be forced out of the system. The ammonia fuel system may include one or more valves configured to control the flow of ammonia as the ammonia is forced out of the ammonia fuel system.

The device may further include a fuel valve train and recirculation to manage ammonia that does not need to be expelled. This could be, for example, ammonia present in parts of the ammonia fuel system, typically relatively close to the fuel tank. This ammonia typically does not pick up too much dust and water and can usually be returned to the fuel tank.

The mixture of ammonia and inert gas may include gaseous ammonia, liquid ammonia, and inert gas.

The apparatus may further include an evaporator configured to evaporate liquid ammonia into gaseous ammonia to provide a gaseous mixture of ammonia and inert gas to be fed to the burner. It is typically not optimal for the burner that the mixture contains both liquid and gaseous ammonia. Therefore, burners typically require liquid or gas, but typically do not work well with mixtures of liquid and gas. Therefore, if a mixture may contain both a liquid and a gas, it may need to be converted to either the liquid or the gas. By introducing an evaporator into the device, liquid ammonia can be evaporated into gaseous ammonia so that the purge supplied to the burner contains only purge gas. Accordingly, the evaporator may be advantageous in that only the gaseous purge is received by the burner. Preferably, the evaporator is configured such that purge gas is supplied to the evaporator before it is supplied to the purge gas inlet.

The apparatus may additionally or alternatively include a separator configured to separate liquid ammonia from gaseous ammonia and inert gas to provide a gaseous mixture of ammonia and inert gas to be fed to the burner. By introducing a separator in the device, it is possible to separate liquid ammonia from gaseous ammonia and inert gases and thus ensure that the purge supplied to the burner contains only purge gas. The separator may be a gas/liquid separator, typically a drum or tank with a demister at the outlet. The liquid phase of the purge may be connected to the main fuel supply system such that the liquid phase is mixed with the liquid main fuel. It should be noted that the device may include both an evaporator and a separator or only one of them.

The evaporator may, for example, be arranged downstream of the separator such that purge gas from which most of its liquid phase has been removed is supplied to the evaporator before being supplied to the purge gas inlet.

The burner may be a multi-fuel burner configured to burn at least two different fuels one at a time or simultaneously. This is advantageous in that more than one fuel can be configured to power the burner or be combusted by the burner. A multi-fuel burner may be configured to burn at least two different fuels, preferably two different liquid fuels, preferably one at a time. A multi-fuel burner may be configured to burn one or more liquid fuels in combination with the combustion of one or more gaseous fuels, wherein more than one gaseous fuel is being burned at a time, preferably one gaseous fuel at a time. At least one liquid fuel, preferably one liquid fuel, is combusted.

The device may further include a liquid ammonia inlet connected through a liquid ammonia connection to a fuel supply line to allow the liquid ammonia to mix with the fuel. This may be advantageous if the device includes a separator and/or evaporator. In such cases, the liquid ammonia separated from the purge gas may be configured to mix with the fuel and still reach the burner, but in a different mixture compared to the purge gas mixture.

The device may further include a combustion fan configured to provide combustion air to the burner. Combustion fans can be configured to supply a specific amount of combustion air based on pre-established requirements. Preferably, there should be 10-15% more combustion air than fuel in the boiler system. This proportion of combustion air is typically required to completely combust not only the fuel but also the purge gas. If combustion is not complete, the furnace can become dirty and black exhaust gases with higher than desired carbon oxide and CO content can be produced.

The apparatus may further include a gas valve train configured to control the flow of purge gas supplied to the burner from the ammonia fuel system.

The combustion fan may additionally or alternatively be configured to direct purge gas to the burner. The combustion fan may include a purge gas inlet, and the combustion fan may be configured to mix the purge gas with combustion air and provide the mixture of purge gas and combustion air to the burner.

If the combustion fan is configured to direct purge gas to the burner, the gas valve train may be excluded from the device. Instead, the combustion fan may be configured to control and direct the flow of purge gas supplied to the burner from the ammonia fuel system. In the combustion fan, purge gas may be mixed with combustion air. The mixture can be guided to a burner, and the mixture can be combusted by an auxiliary flame. However, it should be noted that the device may include both a combustion fan for delivering purge gas and a gas valve train. The combustion fan may be designed for purge gas. A purge gas inlet included in the combustion fan can ensure optimal mixing with the combustion air. Additionally, the combustion fan may be configured to prevent backflow of purge gas.

Additionally, if the device comprises an evaporator and/or separator, the combustion fan is preferably arranged downstream of the evaporator and/or separator.

The foregoing object is also achieved by a method for combustion of purge gases arising from an ammonia fuel system fueling an ammonia fueled engine, the method comprising:

sustaining an auxiliary flame within a burner included in a boiler system, the auxiliary flame being sustained by fuel supplied by a fuel inlet;

intermittently supplying a purge gas, wherein the purge gas is supplied to the burner from the ammonia fuel system by a purge gas inlet, the purge gas comprising a mixture of ammonia and an inert gas; and

and combusting the ammonia in the burner with an auxiliary flame.

Accordingly, the method includes receiving a purge gas from the ammonia fuel system within the burner before the ammonia is combusted.

According to the method, the boiler system can be configured to operate in at least one of the first mode and the second mode,

The first mode is a heat production mode in which heat is produced,

The second mode is an ammonia safety purge mode where the boiler is kept warm and ready for high speed operation and/or the pilot flame is maintained.

The further preferred embodiments described above in relation to the device can equally be applied to the method.

The device is preferably placed on board. The method is preferably carried out on board a ship. However, it should be noted that neither the device nor the method is limited to use on board ships. The above apparatus and method may also be useful in other applications where engines and boilers are located close to each other. This could also be useful in other marine applications other than ships, for example. It may be a platform, for example of the type used for drilling for oil or gas. The devices and methods may also be useful for terrestrial applications. The devices and methods may be used for logging or mining applications, for example.

In general, all terms used in the claims, unless explicitly defined otherwise in the specification, should be interpreted according to their common meaning in the technical field. Any reference to “[element, device, component, means, step, etc.] modified by an article/definite article” refers to at least one of said element, device, component, means, step, etc., unless explicitly stated otherwise. It should be interpreted as open-ended, referring to a single example. The steps of any method disclosed herein need not be performed in the exact order disclosed unless explicitly stated.

The above objects, features and advantages as well as additional objects, features and advantages of the present invention will be better understood through the following illustrative and non-limiting detailed description of preferred embodiments of the present invention with reference to the accompanying drawings, which are similar to those in the drawings. The same reference numbers will be used for elements.
1 discloses an apparatus for combusting purge gas from an ammonia fueled engine.
Figure 2 discloses a flow diagram illustrating a method for combusting purge gas from an ammonia fueled engine.

The invention will now be described more fully hereinafter with reference to the accompanying drawings, in which a presently preferred embodiment of the invention is shown. However, the invention may be embodied in many different forms and should not be limited to the embodiments presented herein; Rather, these examples are provided for thoroughness and completeness, and to fully convey the scope of the invention to those skilled in the art.

Referring to Figure 1, an apparatus 100 is disclosed for combusting purge gas from an ammonia fuel system 108 that supplies fuel to an ammonia fueled engine 112. Apparatus 100 includes a boiler system 102 and an ammonia fuel system 108. Ammonia fuel system 108 includes an ammonia fueled engine 112.

Purge gas may be generated when the ammonia-fueled engine 112 switches fuel from ammonia to another fuel or when the ammonia-fueled engine 112 is shut down in a controlled manner or as a result of an emergency situation. At this stage, the purge gas is toxic and should therefore not be vented to the atmosphere. Purge gas is typically a mixture of ammonia and an inert gas used to expel ammonia from the ammonia fuel system 108. Ammonia may be liquid ammonia, gaseous ammonia, or mixtures thereof. The inert gas may be nitrogen. It should be noted that the inert gas may be any other inert gas.

Boiler system 102 includes a burner 104, a fuel inlet 111 and a purge gas inlet 121. Burner 104 is configured to combust purge gas arising from ammonia fuel system 108. In other words, burner 104 is configured to combust ammonia in the purge gas. Burner 104 may be a multi-fuel burner configured to burn two different fuels one at a time or simultaneously. Burner 104 may be a pressure spray type. Alternatively, burner 104 may be a vapor atomizing type.

The fuel inlet 111 is configured to supply fuel and thereby sustain an auxiliary flame within the burner 104. The fuel inlet 111 is typically configured to supply fuel continuously, at least continuously in the sense of being able to sustain the auxiliary flame. Fuel may initially be supplied to provide a pilot flame or as main fuel when the burner is operating in an operational mode. The main fuel can act as an auxiliary flame so that the purge gas can be combusted by the auxiliary flame.

The purge gas inlet 121 is preferably separate from the fuel inlet 111. The purge gas inlet 121 is configured to intermittently receive purge gas from the ammonia fuel system 108 and supply the purge gas to the burner 104. The purge gas may be supplied from the ammonia fuel system 108 to the purge gas inlet 121 via the purge gas pipe 123. The piping 123 may be of a double wall type, especially in these portions of the piping 123 if the purge is in a gaseous state.

The fuel inlet 111 may be connected to a fuel source 115, for example a fuel tank, via a fuel supply line 113. Fuel source 115 is configured to supply fuel to burner 104 via fuel inlet 111. Fuels can be liquefied natural gas (LNG), distillates and residual fuels. This may include, for example, diesel, marine diesel fuel (MGO), low sulfur fuel oil (VLSFO) and heavy fuel oil (HFO). The fuel may be biofuel. However, it should be noted that the primary fuel may be another fuel. Fuel may include more than one type of fuel. If the fuel includes more than one form of fuel, fuel inlet 111 may be connected to more than one fuel source. Accordingly, if the fuel includes two types of fuel, one fuel type may be supplied from fuel source 115 and the other fuel form may be supplied from one other fuel source 135. Typically, fuel is supplied to only one burner 104 at a time. Typically, the fuel supply line 113 operates as shown in Figure 1 in that different fuels are supplied one at a time using the same inlet 111, albeit at different times. One conceivable combination is to provide liquid fuel to the inlet 111 via the fuel supply line 113 and simultaneously provide gas via a separate gas inlet such as combustion fan 120. The gas provided via a separate gas inlet, such as combustion fan 120, may be a purge gas and/or may be a gaseous fuel not generated in the purge operation.

However, the fuel supply line 113 shown in Figure 1 would then preferably be used to mix the two types of fuel within the fuel supply line 113, where the other fuel is fed into one other fuel supply line ( 133), and thus the mixture is supplied to the burner 104 through the fuel inlet 111. However, although not shown, the two types of fuel may be supplied to the burner 104 by two different fuel inlets and via two different supply lines. Accordingly, device 100 may include an additional supply line disposed separate from fuel supply line 113 , wherein the additional supply line supplies other fuels from other fuel sources 135 to burner 104 It can be configured to do so. The other fuel may be any of the fuels listed above in relation to fuel. Preferably, where the fuel comprises two forms of fuel, one form may be a liquid fuel and the other form may be a gaseous fuel.

2, a flow diagram 200 is shown by way of example, illustrating a method 200 of combustion of purge gas from an ammonia fuel system 108 that fuels an ammonia fueled engine 112. Boiler system 102 is configured to operate in first mode 201 . Boiler system 102 is configured to operate in second mode 211. Boiler system 102 may be configured to operate in modes other than first mode 201 and second mode 211. The first mode 201 may be a heat production mode in which heat is produced. In this regard, it should be noted that heat production may refer to steam production, hot water heating, thermal fluid heating, or heating of any other medium used in a boiler. The second mode 211 may be an ammonia safety purge mode in which the boiler 106 is kept warm and ready for high speed operation and/or the pilot flame can be sustained. Boiler 106 is included in boiler system 102. In the second mode 211, the boiler can prepare for high-speed operation or prepare for high-speed start-up.

The boiler system 102 may be configured to operate in a first sub-mode 201a and a second sub-mode 201b of the first mode 201 . In the first sub-mode 201a, the main flame is maintained within the burner 104 for heat generation and no purge gas is supplied to the burner 104. The first sub-mode 201a is configured to produce heat from fuel supplied to the burner 104 by the fuel inlet 111. The second sub-mode 201b of the first mode 201 is configured to produce heat from the main fuel and the purge gas, and the purge gas is supplied by the purge gas inlet 121. Accordingly, in the second sub-mode 201b, the main flame is maintained within the burner 104 for heat production and a purge gas is supplied to the burner 104. Ammonia is burned by the main flame, which acts as an auxiliary flame.

The boiler system 102 is configured to ignite the auxiliary flame by first igniting the pilot flame or pilot spark and then igniting the auxiliary flame from the pilot flame. The boiler system 102 is configured to ignite the auxiliary flame directly from the pilot flame when the pilot flame persists and supply purge gas to the burner 104 to burn ammonia with the auxiliary flame.

Accordingly, both the first mode and the second mode are configured to burn ammonia, but have different starting points.

Referring back to FIG. 1 , ammonia fuel system 108 includes an ammonia fuel source 155, a fuel supply system 110, and an ammonia fueled engine 112. Ammonia fuel system 108 may include a purge source 165. Ammonia fuel source 155 may be an ammonia tank and is configured to store ammonia prior to being supplied to ammonia-fueled engine 112. Fuel supply system 110 is configured to supply ammonia into ammonia fuel system 108. The ammonia fueled engine 112 is configured to be powered by ammonia supplied from an ammonia fuel source 155.

Purge source 165 is typically a gas tank containing an inert gas. The inert gas from the purge source 165 is configured to expel ammonia from the ammonia fuel system 108 to the purge gas inlet 121 by flushing the inert gas through the ammonia fuel system 108. Apparatus 100 may include a gas valve train 118 configured to control the flow of purge gas supplied from the ammonia fuel system 108 to the burner 104. As previously discussed, the purge gas is a mixture of ammonia and an inert gas. Ammonia may be liquid ammonia, gaseous ammonia, or mixtures thereof. While ammonia is a mixture of gaseous ammonia and liquid ammonia, the purge gas is a mixture of gas and liquid. The purge gas supplied to the burner 104 must be in gaseous form, and therefore liquid must be removed from the purge gas before being supplied to the burner 104.

Apparatus 100 may include an evaporator 114 configured to evaporate liquid ammonia into gaseous ammonia when present in the mixture. By evaporating liquid ammonia into gaseous ammonia, a gaseous mixture of ammonia and an inert gas can be supplied to burner 104. Evaporator 114 may be disposed within purge gas piping 123 between boiler system 102 and ammonia fuel system 108.

Apparatus 100 may additionally or alternatively include a separator 116 configured to separate liquid ammonia from gaseous ammonia and inert gas when present in the mixture. By separating the liquid ammonia from the gaseous ammonia and the inert gas, a gaseous mixture of ammonia and the inert gas can be supplied to the burner 104. Separator 116 may be disposed in purge gas piping 123 between boiler system 102 and ammonia fuel system 108.

It should be noted that device 100 may include both evaporator 114 and separator 116 or only one of evaporator 114 and separator 116.

Device 100 may include a liquid ammonia inlet 141. The liquid ammonia inlet 141 may be connected to the fuel pipe 133 via the liquid ammonia pipe 143. Liquid ammonia inlet 141 may be configured to supply liquid ammonia from evaporator 114 and/or separator 116 to fuel piping 133 such that the liquid ammonia can be mixed with fuel disposed within fuel piping 133. there is. Accordingly, liquid ammonia can be supplied to the burner 104 as a mixture with fuel.

Apparatus 100 may include a combustion fan 120 . Combustion fan 120 may be configured to provide air to burner 104 for combustion of ammonia. Combustion fan 120 may be configured to supply a specific amount of air based on pre-set requirements. Combustion fan 120 may additionally or alternatively be configured to direct purge gas to burner 104 . The combustion fan may additionally or alternatively be configured to direct purge gas to the burner. Combustion fan 120 may include a purge gas inlet 121, and combustion fan 120 may be configured to mix purge gas with combustion air. Combustion fan 120 may also be configured to direct a mixture of purge gas and combustion air to burner 104 . Those skilled in the art will recognize that the present invention is in no way limited to the preferred embodiments described above. On the contrary, many modifications and variations are possible within the scope of the appended claims.

Claims (14)

An apparatus (100) for burning purge gas generated from an ammonia fuel system (108) that supplies fuel to an ammonia fueled engine (112), the apparatus (100)
As a boiler system 102,
burner (104),
a fuel inlet (111) configured to supply fuel to sustain an auxiliary flame within the burner (104), and
A purge gas inlet 121 configured to intermittently receive purge gas from the ammonia fuel system 108 and supply purge gas to the burner 104, wherein the purge gas comprises a mixture of ammonia and an inert gas. Comprising a boiler system (102), including 121),
Burner 104 is device 100 configured to burn ammonia with an auxiliary flame. 2. The method of claim 1, wherein the boiler system (102) is configured to operate in at least one of the first mode (201) and the second mode (211),
The first mode 201 is a heat production mode in which heat is produced,
The second mode 211 is an ammonia safety purge mode in which the boiler 106 is kept warm and ready for high speed operation and/or the pilot flame is maintained. 3. The method of claim 2, wherein the boiler system (102) is configured to operate in at least one of the first sub-mode (201a) and the second sub-mode (201b) of the first mode (201), wherein the first sub-mode (201) In 201a), the main flame is maintained in the burner 104 for heat production and no purge gas is supplied to the burner 104, and in the second sub-mode 201b, the main flame is maintained in the burner 104 for heat production. Apparatus 100 where purge gas is supplied to the burner 104 and the ammonia is combusted by the main flame acting as an auxiliary flame. The method of claim 2 or 3, wherein the boiler system (102)
Igniting the auxiliary flame by first igniting the pilot flame and then igniting the auxiliary flame from the pilot flame, or, if the pilot flame persists, igniting the auxiliary flame directly from the pilot flame,
Apparatus (100) configured to supply purge gas to a burner (104) to combust ammonia in an auxiliary flame. 5. The method according to any one of claims 1 to 4, wherein the fuel inlet (111) is connected to a fuel source (115, 135) via a fuel supply line (113, 133), and the fuel source (115, 135) is liquefied. A device (100) configured to supply a fuel selected from the group consisting of natural gas (LNG), distillate and residual fuel. 6. The method of any one of claims 1 to 5, further comprising an ammonia fuel system (108), wherein the ammonia fuel system (108)
Ammonia fuel source 155 for storing ammonia,
fuel supply system (110);
Ammonia-fueled engine 112, and
A purge source (165) containing an inert gas, configured to expel ammonia from the ammonia fuel system (108) to the purge gas inlet (121) by flushing the inert gas through the ammonia fuel system (108). Device comprising (100). 7. Apparatus (100) according to any preceding claim, wherein the mixture of ammonia and inert gas comprises gaseous ammonia, liquid ammonia and inert gas. 8. The apparatus of claim 7, wherein the apparatus (100) further comprises an evaporator (114) configured to evaporate liquid ammonia into gaseous ammonia to provide a gaseous mixture of ammonia and inert gas to be fed to the burner (104). 100). 9. The apparatus (100) according to claim 7 or 8, wherein the device (100) comprises a separator (116) configured to separate liquid ammonia from gaseous ammonia and inert gas to provide a gaseous mixture of ammonia and inert gas to be fed to the burner (104). Device 100 further comprising: The method according to any one of claims 1 to 9, wherein the burner (104) is
burning at least two different fuels, preferably two different liquid fuels, preferably one at a time;
Combusting one or more liquid fuels in combination with burning one or more gaseous fuels, so that more than one gaseous fuel, preferably one gaseous fuel, is combusted at a time and more than one liquid fuel, preferably one liquid, at a time. configured to cause fuel to burn
Device 100, which is a multi-fuel burner. 11. The method of any one of claims 1 to 10, further comprising a combustion fan (120), the combustion fan (120) comprising a purge gas inlet (121), the combustion fan (120) comprising a purge gas inlet (121). A device (100) configured to mix with combustion air and provide a mixture of purge gas and combustion air to the burner (104). 12. Apparatus (100) according to any preceding claim, wherein the inert gas is nitrogen. A method (200) for combusting purge gas generated from an ammonia fuel system (108) that supplies fuel to an ammonia fueled engine (112), the method (200) comprising:
sustaining an auxiliary flame within a burner (104) included in the boiler system (102), wherein the auxiliary flame is sustained by fuel supplied by a fuel inlet (111);
intermittently supplying a purge gas, wherein the purge gas is supplied from the ammonia fuel system (108) to the burner (104) by a purge gas inlet (121), the purge gas comprising a mixture of ammonia and an inert gas; and
A method (200) comprising combusting ammonia in a burner (104) with an auxiliary flame. 14. The boiler system (102) of claim 13, wherein the boiler system (102) is configured to operate in at least one of the first mode (201) and the second mode (211),
The first mode 201 is a heat production mode in which heat is produced,
The second mode (211) is an ammonia safety purge mode where the boiler is kept warm and ready for high speed operation and/or the pilot flame is maintained (200).

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