A gas turbine auxiliary system for nh3 conditioning

Abstract

A system for generating power using a gas turbine is disclosed. The system comprises an ammonia-cracking device, to convert at least part of a NH3 stream into H2 and N2, to realize a gas NH3 / H2 / N2 mixture that allows operating the gas turbine in every condition. In one aspect, the cracking reactor is operated to produce an excess of cracked products, said products being used to feed auxiliary services.

Description

A gas turbine auxiliary system for NH conditioningDescriptionTECHNICAL FIELD

[0001] The present disclosure concerns a system for generating power using a gas turbine, wherein the system comprises an ammonia-cracking device or reactor. Embodiments disclosed herein specifically concern a gas turbine auxiliary system for NH3 conditioning, wherein a fuel skid processes an ammonia input stream in order to realize a cracking products gas stream that allows operating the gas turbine in every condition. In particular, embodiments disclosed herein concern a gas turbine auxiliary system for NH3 conditioning, wherein in case the cracking reactor is operated to produce an excess of cracked products, they can be used to feed auxiliary services.BACKGROUND ART

[0002] Gas turbines are commonly used to generate power at power stations by combusting fuel therein. In particular, the basic operation of a gas turbine is a Brayton cycle with air as the working fluid: atmospheric air flows through a compressor that brings it to a higher pressure; energy is then added by injecting fuel into the air in a combustion chamber and igniting it so that a combustion generates a high-temperature flow; this high-temperature pressurized gas enters a turbine, producing a shaft work output in the process, used to drive the compressor; the unused energy comes out in - the exhaust gases that can be repurposed for external work, such as directly producing thrust in a turboj et engine, or rotating a second, independent turbine (known as a power turbine) that can be connected to a fan, propeller, or electrical generator. The purpose of the gas turbine determines the design so that the most desirable split of energy between the thrust and the shaft work is achieved. The fourth step of the Brayton cycle (cooling of the working fluid) is omitted, as gas turbines are open systems that do not reuse the same air.

[0003] Commonly used fuels include natural gas, propane, diesel, biogas and biodiesel. One of the main problems associated with combusting fuels such as these in gas turbines is the resultant production of carbon dioxide (CO2) gas. Increased CO2 levels in the atmosphere are detrimental to the environment and are a known cause ofglobal wanning. As such, there is a need to provide fuels for use in gas turbines which do not generate CO2 upon combustion, or from which CO2 must be removed prior to combustion.

[0004] Carbon-free fuels include ammonia and hydrogen. However, both ammonia and hydrogen have some problems associated with their direct use as fuel in a gas turbine. The main problem associated with the direct use of ammonia as fuel in gas turbines is that during the combustion process ammonia is oxidized to nitrogen oxides NOX, a polluting agent contributing to acid rain and global warming. Additionally, due to the low heat content and low reactivity of ammonia with oxygen, the ammonia combustion within the gas turbine presents stability issues (blow-out) over the entire range of the gas turbine operating conditions. On the other hand, even if the combustion of hydrogen still produces NOXpolluting agents, stability issues (blowout) disappear. Nevertheless, a number of problems is associated with the use of hydrogen as fuel, including storage problems and the fact that hydrogen is an extremely flammable gas. The availability of N2 as inert within the combustion process could help to reduce NOXemissions depending on the type of flame realized in the gas turbine combustor.

[0005] CN107288780A discloses a system for generating power using a gas turbine, wherein ammonia is used as fuel. Upstream the combustion chamber, ammonia is partly decomposed to generate hydrogen within an ammonia cracking device to provide a fuel mixture containing hydrogen and ammonia. Since the fire point of hydrogen is lower than that of ammonia, hydrogen is combusted in the combustion chamber first to release heat to ignite ammonia in the combustion chamber. As a consequence, hydrogen can accelerate the combustion process and, accordingly, the combustion performance of ammonia fuel is improved. In conclusion, the amount of hydrogen supplied is functional to NH3 ignition. However, the system disclosed in CN107288780 does not completely overcome the environmental problems due to the formation of nitrogen oxides due to oxidation of ammonia during the combustion process.

[0006] US11084719B2 discloses a process for generating power using a gas turbine, comprising the steps of: (i) vaporizing and pre-heating liquid ammonia to produce preheated ammonia gas; (ii) introducing the pre-heated ammonia gas into an ammonia- cracking device suitable for converting ammonia gas into a mixture of hydrogen andnitrogen; (iii) converting the pre-heated ammonia gas into a mixture of hydrogen and nitrogen in the device; (iv) cooling the mixture of hydrogen and nitrogen to give a cooled hydrogen and nitrogen mixture; (v) introducing the cooled hydrogen and nitrogen mixture into a gas turbine; and (vi) combusting the cooled hydrogen and nitrogen mixture in the gas turbine to generate power. US11084719B2 also discloses embodiments where the composition of the mixture of hydrogen and nitrogen exiting the ammonia cracking device can be adjusted using purification techniques. However, the composition of the output mixture from the cracking process can be far from optimal for the GT operational requirement.

[0007] US11156168B2 discloses a gas turbine plant that is provided with a gas turbine, a heating device, a decomposition gas line, and a decomposition gas compressor. The heating device heats ammonia and thermally decomposes the ammonia to convert the ammonia into decomposition gas including hydrogen gas and nitrogen gas. The decomposition gas line sends the decomposition gas from the heating device to the gas turbine. The decomposition gas compressor increases the pressure of the decomposition gas to a pressure equal to or higher than a feed pressure at which the decomposition gas is allowed to be fed to the gas turbine. US11156168B2 also discloses a control device that adjust the ratio of the flow rate of the decomposition gas to the flow rate of the whole fuel gas (which includes the natural gas and the decomposition gas). The control of such ratio allows obtaining and regulating a mixture of decomposition gas and natural gas to the combustion chamber. However, combusting natural gas still produces a high level of carbon dioxide, which is released to the atmosphere or requires additional carbon capture systems.

[0008] WO2023281265A1 relates to a propulsion system, for thermally integrating an ammonia based cracking reactor into an engine, such as an engine which may be used in aerospace or other vehicle applications. The propulsion system further comprises a fuel cell module, wherein said ammonia cracking module is thermally balanced with both said engine module and said fuel cell module. Besides the system been suitable just for vehicle or aero-application, the integration between the ammonia cracking module and the fuel cell is made to thermally balance the system, by coupling a heat exchanger downstream a combustion chamber to exchange heat and to power a low pressure turbine. Furthermore, cracked ammonia is delivered firstly to thecombustion chamber and the turbine, then to the heat exchanger and only finally to the fuel cell, in a sequential flow.

[0009] CN114352369B relates to a gas turbine-steam turbine combined power generation system for producing hydrogen through ammonia decomposition and the control method thereof. The system comprises a liquid ammonia providing part, a gasification part, an ammonia decomposition part and a gas turbine power generation unit, that are sequentially arranged, so that hydrogen mixed gas containing hydrogen, nitrogen and gaseous ammonia is obtained through hydrogen production through ammonia decomposition, and combustion power generation is conducted; the steam turbine part and the first steam extraction pipeline are further arranged, and the steam in the steam turbine part is extracted by the first steam extraction pipeline and is output to the gasification part as a heat source for gasifying liquid ammonia in the gasification part, so that independent arrangement of heating equipment is avoided. Furthermore, the excess of hydrogen mixed gas, that can be temporarily stored in the hydrogen storage tank, is either delivered to the ammonia decomposition device or to a Gas turbine generator set, however there is no mention of uses of such excess for other auxiliary services than going to the ammonia decomposition device or GT.

[0010] In conclusion, the prior art solution approaches either negatively affect the operation costs of the system or have an adverse environmental impact. Accordingly, an improved system generating power using a gas turbine and ammonia as fuel to address the issues of real time conditioning NH3 to realize a cracking products gas stream that allows operating the gas turbine in every condition would be beneficial and would be welcomed in the technology. NH3 conditioning needs to be pursued flexibly and regulated at different level along the path towards the turbine, so it is felt the need of a system capable to tune and deliver fuels to the gas turbine at different stages, to improve performances but also abate NOXemission, also by means of NH3 recovery system. More in general, it would be desirable to provide systems adapted to more efficiently address problems entailed by providing an auxiliary system for NH3 conditioning to realize a cracking products gas stream that allows operating the gas turbine in every condition and in case the cracking reactor is operated to produce an excess of cracked products, said products can be used to feed auxiliary services.SUMMARY

[0011] In one aspect, the subject matter disclosed herein is directed to an improved system generating power using a gas turbine and ammonia as fuel wherein the system comprises an ammonia-cracking device or reactor. Embodiments disclosed herein specifically concern a gas turbine auxiliary system for NH3 conditioning, wherein a fuel skid processes an ammonia input stream in order to realize a first cracking products gas stream that allows operating the gas turbine in every condition and in case the cracking reactor is operated to produce an excess of cracked products, said products can be used to feed auxiliary services. In one aspect, cracked products could be a gas mixture of nitrogen and hydrogen and residual ammonia or residual ammonia and at least one between nitrogen and hydrogen, or nitrogen and / or hydrogen.

[0012] In another aspect, the subject matter disclosed herein is directed to an improved system generating power using a gas turbine and ammonia as fuel wherein the fuel skid processes an ammonia input stream in order to realize a first cracking products gas stream that allows operating the gas turbine in every condition, and a second cracking products gas stream containing nitrogen and hydrogen and residual ammonia or residual ammonia and at least one between nitrogen and hydrogen, or nitrogen and hydrogen, that allows operating auxiliary services, for example but not limited, hydrogen storage solutions, hydrogen distribution via pipeline, hydrogen for refueling stations, hydrogen compression for tube trailers refilling station, hydrogen for industry decarbonization (e.g. refinery, steel), nitrogen storage solutions, nitrogen distribution via pipeline, nitrogen for refueling stations, ammonia storage solutions, ammonia distribution via pipeline and ammonia for refueling stations.

[0013] In another aspect, the subject matter disclosed herein considers that the quantity of H2 generated is greater than the quantity required by the gas turbine. In another further aspect, the H2 generated can depend upon exhaust gas availability. In particular, exhaust gas can be directed to the cracking reactor and used to generate a fuel mixture containing hydrogen and nitrogen or hydrogen, nitrogen and ammonia.

[0014] In another aspect, the subject matter disclosed herein considers that the gas turbine is fed with a stream of a gas mixture of nitrogen and hydrogen, wherein the amount of hydrogen is about three times the amount of nitrogen (in volume), and therest coming from the cracker due to the heat in excess will be sent downstream the system for other uses, wherein the unreacted ammonia (if any) will be sent back (recycled) in a cracking reactor.

[0015] In another aspect, the subject matter disclosed herein considers that the gas turbine is fed with a stream of a gas mixture of nitrogen and hydrogen, and a portion or all the unreacted ammonia to be burned in the gas turbine, wherein the gas mixture also comprises ammonia, and wherein the amount of hydrogen is about three times the amount of nitrogen (in volume).

[0016] In another aspect, the subject matter disclosed herein considers that, when the quantity of H2 generated is greater than the quantity required by the gas turbine, the excess is sent downstream the system for other uses. In a preferred embodiment an H2 stream separator separates a stream of H2 up to 100% of composition in H2.BRIEF DESCRIPTION OF THE DRAWINGS

[0017] A more complete appreciation of the disclosed embodiments of the invention and many of the attendant advantages thereof will be readily obtained as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings, wherein:Fig. l illustrates a schematic of a power generating system using a gas turbine and comprising an ammonia cracking device according to a first embodiment;Fig.2 illustrates a schematic of a power generating system using a gas turbine and comprising an ammonia cracking device according to a second embodiment;Fig.3 illustrates a schematic of a power generating system using a gas turbine and comprising an ammonia cracking device according to a third embodiment;Fig.4 illustrates a schematic of a power generating system using a gas turbine and comprising an ammonia cracking device according to a fourth embodiment;Fig.5 illustrates a schematic of a power generating system using a gas turbine and comprising an ammonia cracking device according to a fifth embodiment;Fig.6 illustrates a schematic of a power generating system using a gas turbine and comprising an ammonia cracking device according to a sixth embodiment;Fig.7 illustrates a schematic of a power generating system using a gas turbine and comprising an ammonia cracking device according to an seventh embodiment;Fig.8 illustrates a schematic of a power generating system using a gas turbine and comprising an ammonia cracking device and a fuel cell according to a eighth embodiment;Fig.9 illustrates a schematic of a power generating system using a gas turbine and comprising an ammonia cracking device and a fuel cell according to a ninth embodiment;Fig.10 illustrates a schematic of a power generating system using a gas turbine and comprising an ammonia cracking device and a fuel cell according to a tenth embodiment; andFig.11 illustrates a schematic of a power generating system using a gas turbine and comprising an ammonia cracking device and a fuel cell according to a eleventh embodiment.DETAILED DESCRIPTION OF EMBODIMENTS

[0018] According to one aspect, the present subject matter is directed to a system for generating power using a gas turbine, wherein the system comprises an ammonia- cracking device, to convert at least part of an NFL stream into EL and N2, to realize a first cracking products gas stream that allows operating the gas turbine in every condition wherein the cracking reactor is operated to produce an excess of cracked products, which can be used to feed auxiliary services. In one aspect, cracked products could be a gas mixture of nitrogen and hydrogen and residual ammonia or residual ammonia and at least one between nitrogen and hydrogen, or nitrogen and / or hydrogen.

[0019] In another aspect, the subject matter disclosed herein concerns a gas turbine auxiliary system for NH3 conditioning wherein a NH3 feed stream is cracked into H2 and N2, eventually residual ammonia, through a catalytic cracking reactor or a thermal cracking reactor to obtain a H2 and N2 stream. In particular, downstream the cracking reactor, N2 or H2 can be separated from the H2 and N2 stream, to obtain a cracking products gas stream with a controlled ratio of NH3, H2 and N2 and to additionally allow N2 to be used as a purge gas and H2 to be used to feed auxiliary services.

[0020] Reference now will be made in detail to embodiments of the disclosure, one or more examples of which are illustrated in the drawings. Each example is providedby way of explanation of the disclosure, not limitation of the disclosure. In fact, it will be apparent to those skilled in the art that various modifications and variations can be made in the present disclosure without departing from the scope or spirit of the disclosure. Reference throughout the specification to “one embodiment” or “an embodiment” or “some embodiments” means that the particular feature, structure or characteristic described in connection with an embodiment is included in at least one embodiment of the subject matter disclosed. Thus, the appearance of the phrase “in one embodiment” or “in an embodiment” or “in some embodiments” in various places throughout the specification is not necessarily referring to the same embodiment s). Further, the particular features, structures or characteristics may be combined in any suitable manner in one or more embodiments.

[0021] When introducing elements of various embodiments the articles “a”, “an”, “the”, and “said” are intended to mean that there are one or more of the elements. The terms “comprising”, “including”, and “having” are intended to be inclusive and mean that there may be additional elements other than the listed elements.

[0022] Referring now to the drawings, Fig.l shows a schematic of an exemplary power generating system comprising a gas turbine 100. The gas turbine 100 comprises a compressor, a combustion chamber and an expander. The gas turbine 100 is fed by a first cracking products gas stream through a gas turbine feed line 1. Moreover, a gas turbine auxiliary system for NH3 conditioning is arranged upstream the gas turbine 100, the gas turbine auxiliary system including a NH3 heater / vaporizer / pressurizer 200, to heat and then vaporize a liquid NH3 stream from a NH3 stream line 4, and a cracking reactor 300, which is connected to the NH3 heater / vaporizer / pressurizer through a NH3 heater / vaporizer / pressurizer gas outlet line 5 or cracking reactor feed line 5. According to alternative exemplary embodiments, the NH3 heater / vaporizer / pressurizer is composed of shell-and-tube heat exchangers or plate-heat-exchangers. In some embodiments, a heat transfer fluid of the heater / vaporizer / pressurizer is the gas turbine exhaust gas or another intermediate fluid (like steam or thermal oil). According to an exemplary embodiment the heat exchanger is made in two stages, one to heat-up and vaporize liquid ammonia, the other to restore the initial pressure or eventually increase the ammonia gas pressure. In some embodiments, a storage tank for high pressure ammonia gas is also included into the heater / vaporizer / pressurizer system.

[0023] According to an exemplary embodiment shown in Fig.l, the NH3 cracking reactor 300 is a catalytic or thermal reactor, configured to process ammonia and dissociate it into at least its basic components, namely hydrogen and nitrogen, in presence of a catalyst or under temperature control, according to the reaction:

[0024] The mixture of hydrogen and nitrogen and eventually present unreacted or residual ammonia resulting from the cracking reaction is then directed to the gas turbine 100 through a cracking products gas stream outlet line 7, connected downstream to the gas turbine feed line 1.

[0025] Exhaust gas from the gas turbine 100 is routed to an exhaust gas stream line 15, from which a portion of the exhaust gas stream is split through an exhaust gas heat recovery line 12, which is routed to the cracking reactor 300 and / or the NH3 heater / vaporizer / pressurizer 200. With reference to Fig. l, the exhaust gas heat recovery line 12 is split into a first heat recovery sub-line 13, which is directed to the cracking reactor 300 and a second heat recovery sub-line 14, which is directed to the NH3 heater / vaporizer / pressurizer 200. An amount of exhaust gas exceeding a predetermined threshold of required exhaust gas to be provided to the cracking reactor to run the gas turbine 100, such amount of additional exhaust gas is used to generate an excess of H2 to be delivered to auxiliary services 400, wherein the auxiliary services 400 are, for example but not limited to, hydrogen storage solutions, hydrogen distribution via pipeline, hydrogen for refueling stations, hydrogen compression for tube trailers refilling station, hydrogen for industry decarbonization (e.g., refinery, steel).

[0026] An emergency system (not shown) is arranged along the gas turbine feed line 1 and include a vent and emergency valves to prevent overpressure.

[0027] The gas turbine auxiliary system for NH3 conditioning of Fig.1 operates as follows. The system is started by liquid ammonia being heated / vaporized / pressurized inside the NH3 heater / vaporizer / pressurizer 200 and fed in gaseous state to the NH3 cracking reactor 300. Part of the heat produced by the gas turbine 100 is sent to the NH3 heater / vaporizer / pressurizer 200 and to the NH3 cracking reactor 300. Furtherliquid ammonia is heated, vaporized and pressurized in the vaporizer / pressurizer 200 and the NH3 cracking reactor 300 starts operations feeding gaseous mixture in the cracking products gas stream outlet line 7. A storage drum (not shown) can optionally be arranged along the cracking products gas stream outlet line 7. When pressure in the cracking products gas stream outlet line 7 reaches a threshold value, start-up sequence of the gas turbine can begin. Gas turbine ignition is obtained using as fuel the streams fed through the gas turbine feed line 1. If energy to start-up the NH3 heater / vaporizer / pressurizer 200 and the NH3 cracking reactor 300 is not available, a start-up fuel like natural-gas can be connected to the gas turbine feed line 1 and utilized for gas turbine ignition and ramp-up to gas turbine end-of-sequence or full-speed-no- load condition. Once the gas turbine is ignited, the exhaust gas heat starts to provide energy both to the NH3 heater / vaporizer / pressurizer 200 that heats, vaporizes and pressurizes liquid ammonia to gaseous state ammonia and to the NH3 cracking reactor 300 that cracks gaseous ammonia to a mixture of hydrogen, nitrogen and eventual unreacted or residual ammonia. Once appropriate mixture is created, the flow of the gas NH3 / H2 / N2 mixture stream inside the gas turbine feed line 1 is controlled according to the gas turbine control schedules. During all the gas turbine sequences (ramp-up, load operations, normal shutdown) a gas turbine auxiliary control unit manages the requirements of hydrogen, nitrogen and residual ammonia mixture composition of the gas turbine feed line 1, acting on the parameters of the NH3 cracking reactor 300 and managing the flow ratio between the gas turbine feed line 1 and the auxiliary services 400. The parameters of the NH3 cracking reactor managed by the gas turbine auxiliary control unit are strictly dependent from the NH3 cracking reactor technology. In some embodiments, the parameters of the NH3 cracking reactor comprise the temperature of the reacting ammonia gas at specific sections of the reactor (for example at the inlet section) and the NH3 cracking reactor recycle ratio. Emergency shutdown of the gas turbine 100 enables the immediate isolation of the gas turbine auxiliary system for NH3 conditioning from the gas turbine 100 and the de-energization of the NH3 heater / vaporizer / pressurizer 200 and the NH3 cracking reactor 300 according to its specific safety requirements. In some embodiments the auxiliary control unit could be, for example, a computer or programmable logic controller (PLC).

[0028] The operation of the gas turbine auxiliary system for NH3 conditioning of Fig.1 is controlled through a plurality of control valves. A gas flow valve 21 is arrangedalong the gas turbine feed line 1, to control the flowing of the cracking products gas stream inside the gas turbine feed line 1. A heat recovery flow valve 26 is arranged on the first heat recovery sub-line 13 in order to control the portion of the exhaust gas from the gas turbine 100 that is directed to the NH3 cracking reactor 300 and conversely the portion of exhaust gas directed to the NH3 heater / vaporizer / pressurizer 200. The gas flow valve 21 and the heat recovery flow valve 26 can be electric-actuated valves, pneumatic-actuated valves or hydraulic-actuated valves.

[0029] A control method allows to change the composition of the fuel to the gas turbine and inject ammonia in any ratio according to any eventual combustor and gas turbine requirements (these requirements not being part of the present disclosure).

[0030] With continuing reference to Fig. l, further embodiments of a power generating system are shown in Figs. 2, 3, 4 and 5. The same reference numbers designate the same or corresponding parts, elements or components already illustrated in Fig.l and described above, and which will not be described again. In particular, according to the embodiment shown in Fig.2, a cracking products gas split stream line 310 comes out directly from the cracking reactor and connects the cracking reactor to a separator 700 arranged downstream the cracking products gas split stream line 310, the separator 700 being configured to separate a stream comprising a second gas stream of nitrogen, hydrogen and residual ammonia; or residual ammonia and at least one between nitrogen and hydrogen; or nitrogen and hydrogen; or nitrogen or hydrogen or ammonia. Wherein mixtures and / or purified components allow operating auxiliary services 400, for example but not limited to hydrogen storage solutions, hydrogen distribution via pipeline, hydrogen for refueling stations, hydrogen compression for tube trailers refilling station, hydrogen for industry decarbonization (e.g. refinery or steel), nitrogen storage solutions, nitrogen distribution via pipeline, nitrogen for refueling stations, ammonia storage solutions, ammonia distribution via pipeline and ammonia for refueling station. In particular, as shown in Fig.3, the separator 700 can be configured to separate a NH3 stream to be recycled to the cracking reactor feed line 5 through a NH3 stream recirculation line 320. In the exemplary embodiment shown in Fig.4, the cracking products gas split stream line 310, comprising a gas mixture or a pure gas, connecting the ammonia cracking reactor 200 to the auxiliary services 400, is withdrawn from the cracking products gas stream outlet line 7. Moreover, in the power generating system shown in Fig.5, a flow valve 27 isarranged along the cracking products gas split stream line 310, wherein the flow valve 27 can be electric-actuated valve, pneumatic-actuated valve or hydraulic-actuated valve, among other type of valve. In some embodiments the flow valve can be controlled by an auxiliary control unit, for example, a computer or programmable logic controller (PLC).

[0031] Fig.6 shows a schematic of an exemplary power generating system according to a sixth embodiment. The gas turbine 100 comprises a compressor, a combustion chamber and a turbine. The gas turbine 100 is fed by a cracking products gas stream and a gas N2 stream. The cracking products gas stream is directed to the primary stage of the gas turbine 100 through a gas turbine feed line 1 and the gas N2 stream is directed to the secondary stage of the gas turbine 100 through a gas N2 feed stream line 3. Moreover, a gas turbine auxiliary system for NH3 conditioning is arranged upstream the gas turbine 100, the gas turbine auxiliary system including a NH3 heater / vaporizer / pressurizer 200, to heat and then vaporize a liquid NH3 stream from a NH3 stream line 4, and a cracking reactor 300, which is connected to the NH3 heater / vaporizer / pressurizer through a cracking reactor feed line 5. A separator can be arranged within the cracking reactor 300. The amount of exhaust gas exceeding a predetermined threshold of required exhaust gas to be provided to the cracking reactor to run the gas turbine 100, is used to generate an excess of H2 to be delivered to auxiliary services 400, wherein the auxiliary services 400 are, for example but not limited to, hydrogen storage solutions, hydrogen distribution via pipeline, hydrogen for refueling stations, hydrogen compression for tube trailers refilling station, hydrogen for industry decarbonization (e.g., refinery, steel).

[0032] According to this embodiment, the mixture of hydrogen and nitrogen and unreacted ammonia resulting from the cracking reaction is treated to separate a gas NH3 / H2 / N2 mixture stream and a gas N2 stream. The gas NH3 / H2 / N2 mixture stream from the cracking reactor 300 is directed to the gas turbine 100 through a cracking products gas stream outlet line 7, connected downstream to the gas turbine feed line 1.

[0033] According to alternative embodiments the ammonia input stream can be separated into a first cracking products gas stream that allows operating the gas turbine in every condition, and a second gas stream of nitrogen and hydrogen and residualammonia or residual ammonia and at least one between nitrogen and hydrogen, or nitrogen and hydrogen. The second gas stream is a mixture of gases or pure gases coming out of the separator, wherein the separator can be within the cracking reactor or a separator out of the cracking reactor. In particular, the gas turbine can be fed with a stream composed by H2 and N2 (the amount in volume of hydrogen being about three times the amount of nitrogen), and the rest coming from the cracking reactor due to the heat in excess can be sent downstream the system for other uses, wherein the unreacted, or residual, ammonia (if any) can be sent back (recycled) in the cracking reactor. According to an alternative embodiment, the gas turbine can be fed with a stream composed by H2 and N2 (the amount in volume of hydrogen being about three times the amount of nitrogen), and a portion or all the unreacted ammonia to be burned in the gas turbine.

[0034] According to other alternative embodiments, the ammonia cracking reactor can comprise a H2 stream separator, to separate a H2 stream to be directed to auxiliary services, by means of the cracking products gas split stream line. According to a particular embodiment the amount in volume of hydrogen is 100% of the stream or at least more than three times the amount of nitrogen.

[0035] The separation of nitrogen can be obtained through different technologies, such as a membrane, a condenser, a pressure swing adsorber unit (PSA). According to an exemplary embodiment, the NH3 cracking reactor is a membrane reactor, operating as follows. A membrane separates the reactor into two separate sections. A first section is directly connected to the cracking reactor feed line . Ammonia fed to the membrane reactor is reacted inside the first section. A fraction of nitrogen resulting from the cracking reaction permeates the membrane and passes to a second section of the membrane reactor, separating from hydrogen, unreacted, or residual, ammonia and a remaining fraction of nitrogen, which remain inside the first section of the membrane reactor.

[0036] With continuing reference to Fig.6, the gas N2 stream coming from the separator inside the cracking reactor 300 is directed to the gas turbine 100 through a gas N2 stream outlet line 8, connected downstream to the gas N2 feed stream line 3. A fraction of the gas N2 stream from the cracking reactor 300 can be split and returned to the cracking products gas stream outlet line 7 through a gas N2 bypass line 9, tocontrol the composition of the cracking products gas stream directed to the gas turbine 100 through the gas turbine feed line 1.

[0037] Exhaust gas from the gas turbine 100 is routed to an exhaust gas stream line 15, from which a portion of the exhaust gas stream is split through an exhaust gas heat recovery line 12, which is routed to the cracking reactor 300 and / or the NH3 heater / vaporizer / pressurizer 200. With reference to Fig.7, the exhaust gas heat recovery line 12 is split into a first heat recovery sub-line 13, which is directed to the cracking reactor 300 and a second heat recovery sub-line 14, which is directed to the NH3 heater / vaporizer / pressurizer 200. Also, if the amount of exhaust gas exceeds a predetermined threshold of required exhaust gas to run the gas turbine 100, such amount of additional exhaust gas is used to generate an excess of Eb to be delivered to auxiliary services 400, wherein the auxiliary services 400 are for example but not limited to, hydrogen storage solutions, hydrogen distribution via pipeline, hydrogen for refueling stations, hydrogen compression for tube trailers refilling station, hydrogen for industry decarbonization (e.g., refinery, steel industry).

[0038] An emergency system (not shown) is arranged along the gas turbine feed line 1 and includes a vent and emergency valves to prevent overpressure.

[0039] The gas turbine auxiliary system for NH3 conditioning of Fig.6 operates as follows. The system is started by liquid ammonia being heated / vaporized / pressurized inside the NH3 heater / vaporizer / pressurizer 200 and fed in gaseous state to the NH3 cracking reactor 300. Part of the heat produced by the gas turbine 100 is sent to the NH3 heater / vaporizer / pressurizer 200 and to the NH3 cracking reactor 300. Further liquid ammonia is heated, vaporized and pressurized in the vaporizer / pressurizer 200 and the NH3 cracking reactor 300 starts operations feeding gaseous mixture in the cracking products gas stream outlet line 7. A storage drum (not shown) can optionally be arranged along the cracking products gas stream outlet line 7. When pressure in the cracking products gas stream outlet line 7 reaches a threshold value, start-up sequence of the gas turbine can begin. Gas turbine ignition is obtained using as fuel the streams fed through the gas turbine feed line 1. If energy to start-up the NH3 heater / vaporizer / pressurizer 200 and the NH3 cracking reactor 300 is not available, a start-up fuel like natural-gas can be connected to the gas turbine feed line 1 and utilized for gas turbine ignition and ramp-up to gas turbine end-of-sequence or full-speed-no-load condition. Once the gas turbine is ignited, the exhaust gas heat starts to provide energy both to the NH3 heater / vaporizer / pressurizer 200 that heats, vaporizes and pressurizes liquid ammonia to gaseous state ammonia and to the NH3 cracking reactor 300 that cracks gaseous ammonia to a mixture of hydrogen, nitrogen and unreacted ammonia. Once the appropriate mixture is created, the flow of the cracking products gas stream inside the gas turbine feed line 1 is controlled according to the gas turbine control schedules. During all the gas turbine sequences (ramp-up, load operations, normal shutdown) a gas turbine control system manages the requirements of hydrogen, nitrogen and residual ammonia mixture composition of the gas turbine feed line 1, acting on the parameters of the NH3 cracking reactor 300 and managing the flow ratio between the gas turbine feed line 1 and the auxiliary services 400. Emergency shutdown of the gas turbine enables the immediate isolation of the gas turbine auxiliary system for NH3 conditioning from the gas turbine and the de-energization of the NH3 heater / vaporizer / pressurizer 200 and the NH3 cracking reactor 300 according to its specific safety requirements. The NH3 cracking reactor 300 also separates nitrogen from the gas mixture of hydrogen, nitrogen and unreacted ammonia and therefore provides a stream of N2 in the gas N2 stream outlet line 8, which can be used for different applications, like N2 storage or purging services for the gas turbine.

[0040] The operation of the gas turbine auxiliary system for NH3 conditioning of Fig.6 is controlled through a plurality of control valves. A gas flow valve 21, is arranged along the gas turbine feed line 1, to control the flowing of the cracking products gas stream inside the gas turbine feed line 1. A gas N2 bypass stream flow valve 24 is arranged along the gas N2 bypass line 9 to control the flow of nitrogen of the gas N2 stream outlet line 8 from the NH3 cracking reactor 300 used to mix with the cracking products gas stream directed to the gas turbine 100 through the gas turbine feed line 1. Additionally a gas turbine N2 feed stream flow valve 25 is arranged along the gas N2 feed stream line 3, to control the flow of nitrogen of the gas N2 stream outlet line 8 from the NH3 cracking reactor 300 directed to the gas turbine 100. Finally, a heat recovery flow valve 26 is arranged on the first heat recovery sub-line 13 in order to control the portion of the heat recovery flow of the exhaust gas from the gas turbine 100 that is directed to the NH3 cracking reactor 300 and on the other side the portion of heat recovery flow is directed to the NH3 heater / vaporizer / pressurizer 200. The gas flow valve 21, the gas N2 bypass stream flow valve 24, the gas turbine N2 feed streamflow valve 25 and the heat recovery flow valve 26 can be electric-actuated valves, pneumatic-actuated valves or hydraulic-actuated valves, among other type of valves. In some embodiments the flow valves can be controlled by an auxiliary control unit, for example, a computer or programmable logic controller (PLC).

[0041] A control method allows to change the composition of the fuel to the gas turbine and inject ammonia and nitrogen in any ratio according to any eventual combustor and gas turbine requirements (these requirements not being part of the present disclosure).

[0042] With continuing reference to Figs. 1-6, Fig.7 illustrates an seventh embodiment of a power generating system using a gas turbine and comprising an ammonia cracking device. The same reference numbers designate the same or corresponding parts, elements or components already illustrated in Figs. 1-6 and described above, and which will not be described again.

[0043] The embodiment shown in Fig.7 differs from the embodiment of Fig.6 in that at least part of the gas N2 stream from the cracking reactor 300 is not directed to the gas turbine 100, but is collected and used for different purposes, for example but not limited to, nitrogen storage solutions, nitrogen distribution via pipeline, nitrogen for refueling stations. According to this embodiment, the gas N2 stream outlet line 8 is connected downstream to a gas N2 withdrawal line 3’. A stream valve 25’ is arranged along the gas N2 withdrawal line 3 ’, to control the flow of nitrogen of the gas N2 stream outlet line 8 from the NH3 cracking reactor 300 directed to external uses.

[0044] With continuing reference to Figs. 1-7, Figs. 8-11 illustrates some embodiments of a system comprising a gas turbine 100, a gas turbine auxiliary system for NH3 conditioning, and a fuel cell 500. These embodiments differ from the embodiments of Figs. 1-7 at least in that they further comprise a fuel cell 500. The same reference numbers designate the same or corresponding parts, elements or components already illustrated in Figs. 1-7 and described above.

[0045] Although not shown in Figs. 8-11, it will be apparent to those of ordinary skill in the art that the power generating systems described herein below may comprise a plurality of gas turbines 100 and / or a plurality of fuel cells 500. Each of the one or more gas turbines 100 can operate in power generation mode or as a mechanical drive.The plurality of fuel cells 500 can be of the same type or different type.

[0046] In Fig.8, the fuel cell 500 is arranged downstream the gas turbine 100 and is fed using the separate streams of ammonia and / or hydrogen to generate electrical power and / or heat to power / heat auxiliaries or for other purposes. In this embodiment, the system allows to decompose ammonia at high temperature and operate the fuel cell 500 at high temperature.

[0047] The system generates power, such as mechanical power by means of the gas turbine 100 and / or electrical power by means of at least one of the gas turbine 100 and the fuel cell 500. In this way, when the gas turbine 100 operates in power generation mode or as a mechanical drive, such as for oil & gas applications or industrial applications, the combined usage of the gas turbine 100 and the fuel cell 500 allows to exploit performances of both technologies providing a versatile approach which can suit different scenarios. For example, in liquefied natural gas (LNG) and natural gas (NG) plants the gas turbine(s) 100 can be used for mixed refrigerant (MR) or propane refrigerant (PR) while the fuel cell(s) 500 can be used to power the plant auxiliaries equipped with a storage.

[0048] The gas turbine auxiliary system for NH3 conditioning is arranged upstream the gas turbine 100 and is configured to process an ammonia input stream and obtain a decomposition gas comprising at least hydrogen and nitrogen, preferably a gas NH3, H2, N2 mixture.

[0049] The gas turbine 100 is coupled to the separator and is fed with a gas stream, and preferably with a gas stream comprising hydrogen and / or nitrogen. The turbine, in turn, generates power and heat. The latter can be conveyed to a heat recovery steam generator (HRSG) 110 with a post-firing module to provide sufficient heat to decompose ammonia at high temperature and / or to heat a reactant stream, such as a stream of N2 / NH3 / H2, preferably a stream of H2 or NH3, used within the system.

[0050] As described with reference to Figs. 1-7, in Fig.8 the gas turbine auxiliary system comprises an ammonia cracking reactor 300 that is configured to decompose ammonia into a gas mixture of hydrogen, nitrogen and unreacted, or residual, ammonia to be sent to the heat exchanger 710 and after to the separating module 720. The ammonia cracking reactor 300 can be, for example, a catalytic, a thermal reactor or amembrane reactor.

[0051] The system further comprises a separator configured to separate the gas mixture of hydrogen, nitrogen and unreacted, or residual, ammonia, into separate streams of hydrogen, nitrogen, and ammonia.

[0052] The separator may be provided downstream of the cracking reactor 300 and comprises at least one of a heat exchanger 710; a separating module 720; and a membrane that may be part of the membrane reactor itself or be external to it.

[0053] The heat exchanger 710 may be fed by a second gas products outlet line of the cracking reactor 300 and may, in turn, provide the cooled gas stream to the separating module 720 through a connecting line 75.

[0054] The separating module 720 can be a Pressure Swing Adsorption (PSA) separator that separates the gas species of the gas mixture using pressure according to the species' molecular characteristics and affinity for an adsorbent material provided therewithin. The separating module 720 allows to recover unreacted, or residual, ammonia thus maximizing the overall system efficiency. The separating module 720 can be connected downstream of the heat exchanger 710.

[0055] The heat exchanger 710 is configured to pre-heat the stream of ammonia and / or the stream of hydrogen that enters the fuel cell 500 at a preset temperature according to fuel cell 500 technology / requirements. In this manner, the heat exchanger provides sufficient heat to operate the fuel cell 500 at high temperature, for example a temperature of at least 600°C, preferably between 600°C and 700°C, when the fuel cell 500 is fed with pre-heated ammonia and / or pre-heated hydrogen by the heat exchanger 710. However, as it will be apparent to those of ordinary skill, any gas leakage within the power generation system, such as H2, N2, NH3, and / or the gas stream can be conveyed to the fuel cell 500, after being heated if needed by the fuel cell 500 requirements.

[0056] For example, in Fig.8 the separating module 720 provides separated streams of hydrogen and ammonia to the heat exchanger 710, which in turn heats the corresponding streams to allow high temperature operation of the fuel cell 500. In Fig.8 the stream of ammonia is provided from the separating module 720 to the heatexchanger 710 through the connecting line 74.

[0057] The separator comprises one or more outlet lines for conveying the separate streams of hydrogen, nitrogen, ammonia to the respective module of the power generating system, such as the gas turbine 100, the HRSG 110, the fuel cell 500, and / or the cracking reactor 300. For example, the separator comprises a first separator outlet line 71 and a second separator outlet line 72.

[0058] The first separator outlet line 71, which connects the heat exchanger 710 with the fuel cell 500, conveys the stream of ammonia to the fuel cell 500. The first separator outlet line 71 may also be connected to the cracking reactor 300 and / or the post-firing module through the connecting line 71a, as shown in Fig.8, for conveying the stream of ammonia thereto.

[0059] The second separator outlet line 72 provides a stream of hydrogen to the fuel cell 500. In this embodiment, the second separator outlet line 72 comprises a first outlet section 72a to convey a stream of hydrogen from the separating module 720 to the heat exchanger 710 and a second outlet section 72b to convey the pre-heated stream of hydrogen from the heat exchanger 710 to the fuel cell 500. The second separator outlet line 72 may also be connected to gas turbine 100 and / or post-firing module for conveying at least a portion of the stream of hydrogen to these respective components, as shown in Fig.8.

[0060] The separator may also comprise a third separator outlet line 73 connected to the gas turbine 100 for conveying the stream of nitrogen to the gas turbine 100, as shown in Fig.8.

[0061] The gas turbine 100 may comprise a HRSG 110, to recover at least part of the heat of an exhaust gas stream from the gas turbine 100 and direct the at least part of the heat to the ammonia cracking reactor 300, in order to provide thermal power thereto.

[0062] In some embodiments, in order to further reduce NOXemission from the gas turbine 100, the HRSG 110 may comprise a Selective Catalytic Reduction (SCR) system which provides for selective catalytic reduction of NOXusing ammonia or urea as the reducing agent, especially when the combustion system of the gas turbine is notdry low NOX(DLN) or dry low emissions (DNE). Accordingly, the proposed system configuration shown in Fig.8 allows to further reduce the environmental impact.

[0063] The HRSG 110 may comprise a post-firing module configured to receive and process at least a portion of the stream of hydrogen from the separator outlet line 72 and / or a stream of ammonia from the connecting line 71a with the exhaust gas stream to generate additional heat and convey at least part of the additional heat to the ammonia cracking reactor 300, thus allowing to decompose ammonia at high temperature while increasing the efficiency of the overall system.

[0064] The power generating system may also comprise heat exchangers, such as a second heat exchanger (not shown in Fig.8) configured to preheat an ammonia input stream entering into the ammonia cracking reactor 300 and / or the fuel cell 500 by using the heat generated by the gas turbine auxiliary system and / or the gas turbine 100. Alternatively, the ammonia input stream entering into the ammonia cracking reactor 300 may be provided to the ammonia cracking reactor 300 at the required temperature by an external heating system.

[0065] Alternatively, or in addition, the power generating system may comprise a third heat exchanger 800 to preheat the air entering the fuel cell 500. The third heat exchanger 800 may use at least a part of the power generated by the fuel cell 500 to heat clean air downstream the filter house of the gas turbine 100.

[0066] The remaining part of the heat generated by the fuel cell 500 may be conveyed to the ammonia cracking reactor 300 providing additional heat for decomposing ammonia.

[0067] The power generating system may comprise at least one compression system being configured to adjust a fluid pressure and / or conveying the fluid outside the system for external uses. The fluid may comprise any fluid of the system, such as the gas mixture generated by the gas turbine auxiliary system, the stream of hydrogen, the stream of nitrogen, or the stream of ammonia.

[0068] The power generating system may be equipped with one or more storage units (not shown in Fig.8) for storing NH3, H2, heat, electricity, and / or N2. For example, the first separator outlet line 71 may comprise an ammonia storage system being arrangedalong the outlet line 71, the second separator outlet line 72 may comprise a hydrogen storage system being arranged along the outlet line 72, and the third separator outlet line 73 may comprise a nitrogen storage system being arranged along the outlet line 73.

[0069] With continuing reference to Figs. 1-8, Fig.9 illustrates a ninth embodiment of a power generating system using a gas turbine 100 and comprising an ammonia cracking device 300 and a fuel cell 500. The same reference numbers designate the same or corresponding parts, elements or components already illustrated in Fig.8 and described above, and which will not be described again.

[0070] The embodiment shown in Fig.9 differs from the embodiment of Fig.8 at least in that the system does not comprise a HRSG with a post-firing module. The gas turbine exhaust stream will provide sufficient heat to the ammonia cracking reactor 300 to allow operation of the same. Accordingly, the system shown in Fig.9 allows to decompose ammonia at low temperature while operating the fuel cell 500 at high temperature.

[0071] With continuing reference to Figs. 1-9, Fig.10 illustrates a tenth embodiment of a power generating system using a gas turbine 100 and comprising an ammonia cracking device 300 and a fuel cell 500. The same reference numbers designate the same or corresponding parts, elements or components already illustrated in Figs. 8 and 9 and described above, and which will not be described again.

[0072] The embodiment shown in Fig.10 differs from the embodiment of Fig.9 at least in that does not comprise a first outlet section 72a to convey a stream of hydrogen from the separating module 720 to the heat exchanger 710 and a second outlet section 72b to convey the pre-heated stream of hydrogen from the heat exchanger 710 to the fuel cell 500. The embodiment of Fig.10 further differs in that the separator outlet line 71 is not connected to the fuel cell 500.

[0073] In contrast with Fig.8, in Fig.10 the stream of ammonia and / or hydrogen is not pre-heated, but fed directly by separating module 720 to the fuel cell 500. As such, the stream of ammonia and / or hydrogen is provided at a low temperature, such as a temperature less than 200°C, preferably between 80°C and 200°C, to the fuel cell 500. For example, the stream of hydrogen is provided to the fuel cell 500 using the secondseparator outlet line 72, whereas the stream of ammonia is provided using another outlet line 74, which in this case connects the separating module 720 with the fuel cell 500. The configuration shown in Fig.10 allows to operate the fuel cell 500 at low temperature while operating the ammonia cracking reactor 300 at high temperature.

[0074] With continuing reference to Figs. 1-10, Fig.11 illustrates an eleventh embodiment of a power generating system using a gas turbine 100 and comprising an ammonia cracking device 300 and a fuel cell 500. The same reference numbers designate the same or corresponding parts, elements or components already illustrated in Figs. 8-10 and described above, and which will not be described again.

[0075] The embodiment shown in Fig.11 differs from the embodiment of Fig.8 in that it does not comprise a HRSG with a post-firing module. In Fig.11 the gas turbine exhaust stream will provide sufficient heat to the ammonia cracking reactor 300 to perform low temperature decomposition of ammonia.

[0076] Fig.11 further differs from the embodiment of Fig.8 in that does not comprise a first outlet section 72a to convey a stream of hydrogen from the separating module 720 to the heat exchanger 710 and a second outlet section 72b to convey the pre-heated stream of hydrogen from the heat exchanger 710 to the fuel cell 500. Furthermore, the separator outlet line 71 is not connected to the fuel cell 500.

[0077] In contrast with Fig.8, in Fig.11 the stream of ammonia and / or hydrogen is not pre-heated, but fed directly by separating module 720 to the fuel cell 500. As such, the stream of ammonia and / or hydrogen is provided at a low temperature, such as a temperature less than 200°C, preferably between 80°C and 200°C, to the fuel cell 500. In particular, the stream of hydrogen is provided to the fuel cell 500 using the second separator outlet line 72, whereas the stream of ammonia is provided using another outlet line 74, which in this case connects directly the separating module 720 with the fuel cell 500. The configuration shown in Fig.11 allows to operate the fuel cell 500 at low temperature while operating the ammonia cracking reactor 300 at high temperature.

[0078] While aspects of the invention have been described in terms of various specific embodiments, it will be apparent to those of ordinary skill in the art that many modifications, changes, and omissions are possible without departing from the spirtand scope of the claims.

Claims

CLAIMS1. A power generating system comprising a gas turbine (100) and a gas turbine auxiliary system for NH3 conditioning, wherein the gas turbine auxiliary system for NH3 conditioning is configured to process an ammonia input stream and obtain a decomposition gas comprising at least hydrogen and nitrogen, preferably a gas NH3 / H2 / N2 mixture, the gas turbine auxiliary system for NH3 conditioning comprising an ammonia cracking reactor (300), the ammonia cracking reactor (300) being configured to decompose ammonia into a first cracking products gas stream of hydrogen and nitrogen or hydrogen, nitrogen and residual ammonia, a cracking products gas stream outlet line (7) connecting the ammonia cracking reactor (300) to the gas turbine (100), a cracking products gas split stream line (310) connecting the ammonia cracking reactor (300) to auxiliary services (400).

2. The power generating system of claim 1, wherein the cracking products gas split stream line (310), connecting the ammonia cracking reactor (300) to auxiliary services (400), is withdrawn from the cracking products gas stream outlet line (7).

3. The power generating system of claim 1, wherein the amount of hydrogen in the first cracking products gas stream of hydrogen and nitrogen or hydrogen, nitrogen and residual ammonia is about three times the amount of nitrogen.

4. The power generating system of any of the previous claims, comprising a separator (700), between the ammonia cracking reactor (300) and auxiliary services (400), configured to obtain at least a stream comprising a second cracking products gas stream of nitrogen, hydrogen and residual ammonia; or residual ammonia and at least one between nitrogen and hydrogen; or nitrogen; or hydrogen; such second cracking products gas stream being delivered to auxiliary services (400).

5. The power generating system of claim 4, wherein the amount of hydrogen in the second cracking products gas stream of hydrogen and nitrogen or hydrogen, nitrogen and residual ammonia is about three times the amount of nitrogen.

6. The power generating system of claim 4, wherein the separator (700) is a NH3 stream separator.

7. The power generating system of claim 6, wherein the NH3 stream separator is a membrane.

8. The power generating system of claim 6, wherein the NH3 stream separator is a condenser.

9. The power generating system of claim 6, wherein the NH3 stream separator is a Pressure Swing Adsorption, PSA.

10. The power generating system of any of preceding claims 6-9, wherein the NH3 stream separator separates a NH3 stream to be recycled to the cracking reactor feed line (5) by means of a NH3 stream line (320).

11. The power generating system of claim 4, wherein the separator (700) is a H2 stream separator.

12. The power generating system of claim 11, wherein the H2 stream separator is a membrane.

13. The power generating system of claim 11, wherein the H2 stream separator is a PSA.

14. The power generating system of any one of claims 6-11, wherein the H2 stream separator separates a H2 stream to be directed to auxiliary services (400), by means of a hydrogen stream line.

15. The power generating system of claim 4, wherein nitrogen separated from the first cracking products gas stream of hydrogen and nitrogen or the gas mixture of hydrogen, nitrogen and residual ammonia is withdrawn from the ammonia cracking reactor (300) through a nitrogen stream line (8), the nitrogen stream line (8) being connected to the gas turbine feed line (1) through a gas nitrogen feed line (9) upstream the gas turbine (100) and / or to the gas turbine (100) through a gas nitrogen feed line (3) and / or to a gas N2 withdrawal line (3’).

16. The power generating system of claim 4, wherein the crackingproducts gas split stream line (310) is a nitrogen stream line.

17. The power generating system of any of the previous claims, also comprising a NH3 heater / vaporizer / pressurizer (200) configured to heat / vaporize / pressurize an at least partially liquid ammonia input stream.

18. The power generating system of any of the previous claims, also comprising a NH3 pressurizer configured to pressurize a gas ammonia input stream.

19. The power generating system of any of the previous claims, wherein a plurality of flow valves (21, 24, 25, 26, 27), is controlled by an auxiliary control unit.

20. The power generating system of claim 19, wherein the plurality of flow valves (21, 24, 25, 26, 27) comprises a gas flow valve (21) arranged along the gas turbine feed line (1) and a flow valve (27) arranged along the cracking products gas split stream line (310).

21. The power generating system of claim 19, wherein the plurality of flow valves (21, 24, 25, 26, 27) also comprises a gas N2 bypass stream flow valve (24) arranged along the gas N2 bypass line (9) and / or a gas turbine N2 feed stream flow valve (25) is arranged along the gas N2 feed stream line (3).

22. The power generating system of any of the previous claims, also comprising a heat recovery system configured to recover at least part of the heat of an exhaust gas stream from the gas turbine (100), the heat recovery system comprising a first heat recovery sub-line (13), configured to convey a first portion of the exhaust gas stream to the cracking reactor (300) and / or a second heat recovery sub-line (14), configured to convey a second portion of the exhaust gas stream to the NH3 heater / vaporizer / pressurizer (200).

23. The power generating system of claim 22, also comprising at least one heat recovery flow valve (26).

24. The power generating system of claim 23, wherein the at least one heat recovery flow valve (26) is arranged on the first heat recovery sub-line (13) or on the second heat recovery sub-line (14).

25. The power generating system of claim 4, also comprising: a fuel cell (500), wherein the separator (700), coupled to the gas turbine (100), also comprises at least one of: a first separator outlet line (71, 74) connected to said fuel cell (500) for conveying said stream of ammonia to said fuel cell (500), and a second separator outlet line (72, 72b) connected to said fuel cell (500) for conveying said stream of hydrogen to said fuel cell (500).

26. The power generating system of claim 25, wherein the separator comprises a membrane.

27. The power generating system of claims 25 or 26, further comprising a gas stream outlet line of the cracking reactor (300) being connected to said separator, and wherein the separator comprises at least one of: a heat exchanger (710); and a separating module (720), preferably wherein the separating module (720) is a Pressure Swing Adsorption, PSA, said separating module being configured to separate the gas stream mixture using pressure.

28. The power generating system of claim 27, wherein the heat exchanger (710) is configured to provide a cooled gas stream mixture to the separating module (720).

29. The power generating system of claim 27 or 28, wherein the heat exchanger (710) is configured to heat at least one of said stream of ammonia and said stream of hydrogen at a temperature at least sufficient for operating the fuel cell (500) at high temperature.

30. The power generating system of claim 27 or 28, wherein the separating module (720) is configured to provide the separated stream of hydrogen and / or ammonia to the fuel cell (500) at a temperature sufficient for operating the fuel cell (500) at low temperature.

31. The power generating system of any one of the preceding claims, further comprising at least one compression system being configured to:adjust a fluid pressure; and convey the fluid outside the system for external uses; wherein said fluid comprises at least one of the gas mixtures, the stream of hydrogen, the stream of nitrogen, and the stream of ammonia.

32. The power generating system of any of claims 25 to 31, wherein the first separator outlet line (71) comprises an ammonia storage system being arranged along said outlet line (71).

33. The power generating system of any of claims 25 to 32, wherein the second separator outlet line (72, 72b) comprises a hydrogen storage system being arranged along said outlet line (72, 72b).

34. The power generating system of any of claims 25 to 33, wherein said separator comprises a third separator outlet line (73) connected to said gas turbine (100) for conveying said stream of nitrogen to said gas turbine (100), preferably wherein the third separator outlet line (73) comprises a nitrogen storage system being arranged along said outlet line.

35. The power generating system of any one of the preceding claims, wherein the gas turbine (100) comprises a heat recovery steam generator HRSG (110) to recover at least part of the heat of an exhaust gas stream (15) from the gas turbine (100) and convey said at least part of the heat to said ammonia cracking reactor (300).

36. The power generating system of claim 35, wherein the HRSG comprises a Selective Catalytic Reduction, SCR, system.

37. The power generating system of claim 35 or 36, wherein the HRSG (110) comprises a post-firing module configured to receive and process at least a portion of said stream of hydrogen and / or ammonia to generate additional heat and convey at least part of said additional heat to said ammonia cracking reactor (300).

38. The power generating system of any of claims 35 to 37, further comprising a second heat exchanger being configured to preheat an ammonia input stream entering into the ammonia cracking reactor (300) and / or the fuel cell (500) and wherein the gas turbine auxiliary system is configured to generate heat and convey atleast part of said heat to said second heat exchanger.

39. The power generating system of any of claims 35 to 38, comprising a third heat exchanger (800) to preheat the air entering the fuel cell (500), wherein at least a part of the heat generated by the fuel cell (500) is conveyed to said third heat exchanger (800), and preferably wherein a remaining part of the heat generated by the fuel cell (500) is conveyed to said ammonia cracking reactor (300).

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