System and method for utilizing catalytic reactor layers

Abstract

System, comprehensive: a catalytic reactor (14) configured to be mounted on a combustion chamber (30), the catalytic reactor (14) comprising: a catalyst (56) designed to reduce emissions associated with combustion in the combustion chamber (30); a first sacrificial layer (58) which was arranged above the catalyst (56) in the combustion chamber (30) prior to the installation of the catalytic reactor (14); and a second sacrificial layer (70) which was arranged above the first sacrificial layer (58) prior to the assembly of the catalytic reactor (14) on the combustion chamber (30), wherein the first and the second sacrificial layer (58, 70) differ from each other, wherein the second sacrificial layer (70) has a higher temperature resistance than the first sacrificial layer (58); wherein the first and second sacrificial layers (58, 70) are removable, while the catalytic reactor (14) is mounted on the combustion chamber (30) without damaging the catalyst (56).

Description

GENERAL STATE OF THE ART

[0001] The subject of the invention described herein is catalytic reactors and in particular sacrificial layers that can be used in catalytic reactors.

[0002] Catalytic reactors can be used in general during combustion processes, for example in gas turbines or catalytic reformers, to reduce emissions produced during combustion. During combustion, compounds such as nitric oxide and nitrogen dioxide (commonly known as NO₂) can be released. x These compounds are formed at high temperatures, for example, temperatures above approximately 1430 °C. Catalytic reactors can employ catalysts that lower the reaction temperatures required for combustion, thus reducing the formation of these compounds. In certain combustion processes, it may be desirable to protect the catalysts in the catalytic reactors.

[0003] US 2010 / 0180597 A1 discloses a system with a catalytic reactor mounted in the combustion chamber of a gas turbine and designed to reduce emissions during combustion processes in the combustion chamber. The catalytic reactor includes a catalyst on which a sacrificial coating is deposited in one or more layers. After a certain operating time (e.g., after the combustion engine has been started up), during which the sacrificial layer protects the catalyst from contamination, the sacrificial layer can be removed without damaging the underlying catalyst layer. For this purpose, the sacrificial layer can be water-soluble and removed by washing while the catalytic reactor is mounted on the combustion chamber. BRIEF DESCRIPTION OF THE INVENTION

[0004] Certain embodiments whose scope corresponds to that of the originally claimed invention are summarized below. These embodiments are not intended to limit the scope of the claimed invention, but rather merely to provide a brief summary of possible forms of the invention. Thus, the invention may comprise various forms that are similar to or may differ from the embodiments described below.

[0005] In a first embodiment, a system comprises a catalytic reactor configured for mounting on a combustion chamber. The catalytic reactor includes a catalyst configured to reduce emissions associated with combustion in the combustion chamber. The catalytic reactor also includes a first sacrificial layer, which is positioned over the catalyst prior to the installation of the catalytic reactor in the combustion chamber, and a second sacrificial layer, which is positioned over the first sacrificial layer prior to the installation of the catalytic reactor on the combustion chamber. The first and second sacrificial layers differ from each other, with the second sacrificial layer exhibiting higher temperature resistance than the first sacrificial layer. The first and second sacrificial layers are removable while the catalytic reactor is mounted on the combustion chamber without damaging the catalyst.

[0006] The aforementioned system can include a third sacrificial layer, which is placed above the second sacrificial layer prior to the assembly of the catalytic reactor on the combustion chamber, wherein the second and third sacrificial layers are different from each other, and wherein the first, second and third sacrificial layers are removable while the catalytic reactor is mounted on the combustion chamber without damaging the catalyst.

[0007] In one of the previously mentioned systems, the second sacrificial layer can be degraded over time under the influence of temperature, and the first sacrificial layer is water-soluble.

[0008] One of the aforementioned systems may include a third sacrificial layer, which is arranged above the second sacrificial layer prior to the assembly of the catalytic reactor on the combustion chamber, wherein the first, second and third sacrificial layers are removable while the catalytic reactor is mounted on the combustion chamber without damaging the catalyst, and wherein the third sacrificial layer may contain a catalytic material.

[0009] One of the aforementioned systems can comprise a second sacrificial layer arranged above the first sacrificial layer and a third sacrificial layer arranged above the second sacrificial layer, wherein the first, second and / or third sacrificial layer is water-soluble and the first, second and / or third sacrificial layer contains a catalytic material.

[0010] In any of the aforementioned systems, the first sacrificial layer may contain at least one of the following materials: an inorganic oxide, a silicate, an inorganic halide, a metal nitrate, a metal chlorate, a metal acetate, a metal sulfate, a metal hydroxide, an organometallic compound, an organic-inorganic mixed oxide composition, a halogenated carbon compound, or a combination thereof.

[0011] In one of the previously mentioned systems, the first sacrificial layer can contain unfired ceramic.

[0012] In one of the previously mentioned systems, the combustion chamber can incorporate the catalytic reactor.

[0013] One of the previously mentioned systems may include a gas turbine that features the combustion chamber with the catalytic reactor.

[0014] In a second embodiment, a method comprises applying a first sacrificial layer over a catalyst of a catalytic reactor, applying a second sacrificial layer over the first sacrificial layer, wherein the first and second sacrificial layers differ from each other, the second sacrificial layer having a higher temperature resistance than the first sacrificial layer, and mounting the catalytic reactor to a combustion chamber after the application of the first and second sacrificial layers. The first and second sacrificial layers are removable while the catalytic reactor is mounted to the combustion chamber without damaging the catalyst.

[0015] In the process, the application of the first sacrificial layer can involve the application of a green suspension or sol-gel to form the first sacrificial layer over the catalyst.

[0016] In one of the previously mentioned processes, the first sacrificial layer contains at least one of the following materials: an inorganic oxide, a silicate, an inorganic halide, a metal nitrate, a metal chlorate, a metal acetate, a metal sulfate, a metal hydroxide, an organometallic compound, an organic-inorganic mixed oxide composition, or a combination thereof.

[0017] One of the previously mentioned methods may involve applying a second sacrificial layer over the first sacrificial layer prior to mounting the catalytic reactor to the combustion chamber, with the first and second sacrificial layers being different from each other.

[0018] One of the previously mentioned methods may involve removing the second sacrificial layer with a first stripping process and subsequently removing the first sacrificial layer with a second stripping process.

[0019] In one of the previously mentioned processes, the first stripping process may involve the temporal thermal degradation of the second sacrificial layer under the influence of temperature in order to remove the second sacrificial layer, and the second stripping process may involve washing the first sacrificial layer with water in order to remove the first sacrificial layer after the removal of the second sacrificial layer.

[0020] One of the previously mentioned methods may involve removing the first sacrificial layer after the catalytic reactor has been mounted on the combustion chamber in order to expose the catalyst.

[0021] In one of the previously mentioned methods, the removal of the first sacrificial layer may involve washing with water, the application of vibrations, the application of pressure waves, thermal degradation, abrasion, the use of a tearing process, or a combination thereof.

[0022] One of the previously mentioned methods may involve operating a gas turbine that has the combustion chamber with the catalytic reactor, wherein the first sacrificial layer protects the catalyst during a first combustion period in the combustion chamber to prevent fouling of the catalyst.

[0023] In a third embodiment, a method comprises protecting a catalyst of a catalytic reactor mounted on a combustion chamber with at least a first sacrificial layer applied over the catalyst and a second sacrificial layer applied over the first sacrificial layer during a first combustion period in the combustion chamber, wherein the first and second sacrificial layers differ from each other, the second sacrificial layer having a higher temperature resistance than the first sacrificial layer, and reducing emissions with the catalyst during a second combustion period after the first combustion period in the combustion chamber. At least the second sacrificial layer is removed from the catalyst after the first period and before the second period, while the catalytic reactor remains mounted on the combustion chamber. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] These and other features, aspects and advantages of the present invention are better understood with the following detailed description with reference to the accompanying drawings, in which the same reference numerals represent the same parts in all drawings, wherein: Fig. 1 a simplified flow diagram of an embodiment of a gas turbine with a catalytic reactor in which sacrificial layers can be used; Fig. 2 a sectional view through the longitudinal axis of an embodiment of the gas turbine of Fig. 1 is; Fig. 3 a detailed view of a section of the gas turbine of Fig. Figure 2 shows a combustion chamber with the catalytic reactor; Fig. 4 a sectional view of a section of the in Fig.3 catalytic reactor shown according to embodiments which as such do not belong to the claimed invention; Fig. 5 is a flowchart illustrating an exemplary method for using a sacrificial layer according to embodiments which as such do not belong to the claimed invention; Fig. 6 a sectional view of a section of the in Fig. 3 depicted catalytic reactor, in which several sacrificial layers are shown according to certain embodiments; Fig. 7 a sectional view of a section of the in Fig. 3 depicted catalytic reactor, in which several sacrificial layers are shown according to certain embodiments; Fig. 8 is a flowchart illustrating an exemplary method for using multiple sacrificial layers according to certain embodiments; Fig.9 is a flowchart illustrating an exemplary method for applying multiple sacrificial layers according to certain embodiments; and Fig. 10 is a flowchart in which an exemplary method for operating a combustion system with a catalytic reactor and several sacrificial layers according to certain embodiments is shown. DETAILED DESCRIPTION OF THE INVENTION

[0025] One or more specific embodiments of the present invention are described below. To keep these embodiments concise, not all features of an actual embodiment may be described. It should be recognized that, as with any engineering or design project, the development of such an actual embodiment requires numerous implementation-specific decisions to be made in order to achieve the developers' specific objectives, such as compliance with system-related and company-related requirements, which may differ from one embodiment to the next. It should also be recognized that this development effort could be complex and time-consuming for a person skilled in the art who benefits from this disclosure, but would nevertheless be routine in design, manufacturing, and production.

[0026] When elements of different embodiments of the present invention are presented, the articles "a", "an", "the", "the", and "the" shall mean that one or more of the elements are present. The terms "comprise", "contain", and "have" shall be inclusive and mean that additional elements besides those listed may be present.

[0027] The present disclosure relates to sacrificial layers that can be used in catalytic reactors to protect the catalyst. During certain operating periods, for example, during the start-up or commissioning of a combustion chamber in a gas turbine or after the installation of a new compressor, impurities and / or particles can be transported downstream to the combustion chamber in higher concentrations. These impurities and / or particles can flow into the catalytic reactor and can contaminate or otherwise damage the catalyst within the reactor through deposition. For example, certain particles can adhere to the catalyst, cover the catalyst surface, and thereby significantly reduce the area available for interaction with the catalyst during combustion.It may therefore be desirable to apply one or more sacrificial layers to the catalyst before these operating times in order to protect the catalyst during these operating times.

[0028] Sacrificial layers can be applied during the manufacture, maintenance, or repair of the catalytic reactor. In particular, the sacrificial layer can be applied over the catalyst surface during the manufacturing process. Sacrificial layers can be applied to the catalytic reactor, for example, before its installation in the combustion chamber and / or before the combustion chamber is installed in the gas turbine. As another example, sacrificial layers can be applied to the catalytic reactor while the combustion chamber and / or the gas turbine are shut down or out of operation, i.e., not actively burning a fuel-air mixture to generate power, which may occur during a maintenance or repair operation.

[0029] The sacrificial layers are therefore positioned directly above the catalytic reactor at the time of start-up of the combustion chamber and / or the gas turbine. After the operating period, when the desired catalyst protection ends—for example, after the first approximately 10 to 1000, 25 to 500, or 50 to 200 operating hours for a new gas turbine—the sacrificial layers can be removed using one or more stripping methods (e.g., washing with water, thermal removal, chemical removal, removal by pressure waves, etc.). However, the period for which the sacrificial layers remain in place can vary and would depend on the application. In particular, the sacrificial layers may have a rupturable or easily cracked layer that can be chemically or mechanically removed while the catalytic reactor is installed in the combustion chamber.The sacrificial layers may, for example, be water-soluble and thus removed during compressor, combustion chamber, and / or turbine cleaning. The sacrificial layers may also be removed by heat, for example, by gradual thermal degradation of the sacrificial layer over a limited period until it is completely removed. Furthermore, the sacrificial layers may be removed by mechanical vibrations and / or pressure waves, for example, by applying sound waves from a sound horn or loudspeaker, or by applying pressure waves from a combustion-driven device. In some embodiments, the sacrificial layers may be removed by inducing combustion dynamics in the combustion chamber, thereby generating pressure waves and vibrations to assist in the detachment of the sacrificial layers from the catalytic reactor.In certain embodiments, the sacrificial layer can be catalytically active to provide catalytic properties while protecting the catalyst. For example, while the sacrificial layer is positioned above the catalyst, the catalyst's surface may be obscured, thus reducing its catalytic benefits. The catalytic properties of sacrificial layers can be used to temporarily replace or supplement the catalyst to lower the reaction temperature and reduce emissions while the sacrificial layer is present in the catalytic reactor.

[0030] Sacrificial layers can generally be applied to catalytic reactors within various combustion settings, such as gas turbines, machines and reformers. Fig.Figure 1 illustrates an exemplary application for sacrificial layers and shows a system 10 comprising a gas turbine 12 in which catalytic reactors 14 with sacrificial layers can be used. The sacrificial layers can include sacrificial layers applied before the assembly and operation of the gas turbine 12, as well as sacrificial layers applied after the assembly of the gas turbine 12. In certain embodiments, the system 10 can comprise an aircraft, a watercraft, a locomotive, a power generation system, or combinations thereof. The gas turbine 12 shown has an air inlet section 16, a compressor 18, a combustion chamber section 20, a turbine 22, and an outlet section 24. The turbine 22 is coupled to the compressor 18 via a shaft 26.

[0031] As indicated by the arrows, air can flow through the inlet section 16 into the gas turbine 12 and into the compressor 18, which compresses the air before it enters the combustion chamber section 20. The combustion chamber section 20 shown has a combustion chamber casing 28 arranged concentrically or annularly around the shaft 26 between the compressor 18 and the turbine 22. The compressed air from the compressor 18 flows into combustion chambers 30, where it can mix with fuel and combust in the catalytic reactors 14. Some or all of the combustion can take place in the catalytic reactors 14, which, as mentioned previously, can reduce downstream temperatures to lower emissions.

[0032] From combustion chamber section 20, the hot combustion gases flow through turbine 22 and drive compressor 18 via shaft 26. The combustion gases can, for example, exert driving forces on turbine impeller blades in turbine 22 to rotate shaft 26. After passing through turbine 22, the hot combustion gases can exit gas turbine 12 through exhaust section 24.

[0033] Fig. Figure 2 is a cross-sectional and side view of an embodiment of the gas turbine 12. Fig.1 along a longitudinal axis 29. The gas turbine 12 has one or more fuel nozzles 32 located in the combustion chamber section 20. In certain embodiments, the gas turbine 12 can have several combustion chambers 30 arranged in an annular configuration. Each combustion chamber 30 can further have several fuel nozzles 32 attached to the cover of each combustion chamber 30 in an annular or other arrangement.

[0034] As previously referred to Fig.As described in Figure 1, air can flow into the turbine 12 through the air inlet section 16 and be compressed by the compressor 18. The compressed air from the compressor 18 can then be directed into the combustion chamber section 20, where it can be mixed with fuel. The fuel nozzles 32 can, for example, inject a fuel-air mixture into the combustion chambers 30 in a suitable ratio for optimal combustion, optimal emissions, optimal fuel consumption, and optimal power output. In the combustion chambers 30, the fuel-air mixture can combust in the catalytic reactors 14 to produce hot, pressurized exhaust gases. The catalytic reactors 14 can generally contain one or more catalysts, which lower the reaction temperatures and thereby reduce the formation of undesirable byproducts such as NOₓ. xand reduces or decreases carbon monoxide and / or improves or improves flame stability. Combustion can also take place in the combustion chambers 30 outside the catalytic reactors 14. The hot, pressurized exhaust gases generated in the combustion reaction can leave the combustion chamber section 20 and flow through a transition section 36 to the turbine 22. In the turbine 22, the pressurized exhaust gases can rotate blades 38, which run radially in the turbine 22 around the shaft 26 ( Fig. 1) to rotate before they flow out through outlet section 24.

[0035] A detailed view of an embodiment of the combustion chamber section 20 is shown in Fig.Figure 3 shows that the fuel premix nozzles 32 are mounted on a cover 42 near the head end of the combustion chamber 30. Compressed fuel is directed through the cover 42 to each of the fuel nozzles 32, which distribute a premixed air-fuel mixture into the combustion chamber 30. The combustion chamber 30 has a combustion chamber 44, which is generally defined by a housing 46, a flame tube 48, and a baffle plate 50. In certain embodiments, the baffle plate 50 can be arranged coaxially around the flame tube 48 to direct air from the compressor through holes or other openings in the flame tube premix section 45 into the combustion chamber 44, as generally indicated by the arrows.

[0036] Fuel nozzles 32 can distribute pressurized fuel upstream of the catalytic reactor 14 to enable premixing of fuel and air upstream of the reactor. The fuel-air mixture can then flow through the catalytic reactor 14 in the combustion chamber 44. The catalytic reactor 14 can generally contain a catalyst that accelerates the combustion reactions to reduce emissions. The catalyst can generally promote stable reactions between fuel and air at low temperatures to generate combustion exhaust gases 52. The combustion exhaust gases 52 can flow from the catalytic reactor 14 through the main section of the combustion chamber 44 and the transition section 36, where further combustion can occur. For example, partially combusted or reacted exhaust gases 52 can thermally combust in the combustion chamber 44 and / or the transition section 36.

[0037] The catalytic reactor 14 can be arranged along the flame tube 48 and / or transversely across the space 44 and can therefore be mounted or attached to the combustion chamber section 20 in various ways. The catalytic reactor 14 can, for example, generally comprise a ceramic or metallic support coated with a catalyst, forming a catalyst bed. The catalyst bed can have any suitable structure, such as honeycomb cells, a fixed bed, reticulated foam, a long tube, multiple tubes, a grid or sieve, a monolith, a cylindrical shape, a plate, or the like. The support can be composed of or manufactured from high-temperature materials such as metal alloys, ceramics, metal oxides, intermetallic materials, carbides, nitrides, and the like. The catalyst bed structure can generally be coated with a reaction catalyst to accelerate the combustion reactions.The catalyst bed can, for example, consist of a cylinder with a cross-section containing honeycomb-shaped cells coated with a reaction catalyst. The type of catalyst can be specifically tailored to the combustion application and may vary depending on the type of fuel used. For instance, the catalyst for a hydrocarbon fuel may contain elements such as zirconium, vanadium, chromium, manganese, copper, platinum, osmium, iridium, rhodium, cerium, lanthanum, other elements of the lanthanum series, copper, nickel, iron, magnesium, platinum, and platinum group metals. The catalyst may also contain further active components consisting of precious metals, group VIII precious metals, base metals, metal oxides, or any combination thereof.

[0038] In other embodiments, the position of the catalytic reactor 14 within the combustion chamber section 20 can differ. For example, the reactor can be generally located upstream or downstream of the main combustion chamber 44. Furthermore, the catalytic reactor can be used in rich or lean combustion environments. Additional components such as preburners, premixers, multiple stages, one or more catalytic pilot burners, and the like can also be included in the combustion chamber section 20. In certain embodiments, the catalytic reactor 14 can be located within one of these additional components. For example, the catalytic reactor can be located within a rich combustion catalytic reactor, a lean combustion catalytic reactor, a premixed combustion chamber, a catalytic pilot burner, or a preburner.Certain combustion chambers 30 may further comprise several catalytic reactors 14 made of the same or different catalyst materials, each having the same or different sacrificial layers. For example, a first catalytic reactor 14 may be made of a first catalytic material with a first group of sacrificial layers, a second catalytic reactor 14 may be made of a second catalytic material with a second group of sacrificial layers, a third catalytic reactor 14 may be made of a third catalytic material with a third group of sacrificial layers, and so on. Each series of sacrificial layers may comprise 1, 2, 3, 4, 5 or more sacrificial layers made of the same or different sacrificial materials and produced using the same or different stripping processes (e.g.,(Removable by washing with water, chemical removal, thermal removal, removal by pressure waves, etc.)

[0039] Fig. Figure 4 is a sectional view through a section of the catalytic reactor 14 according to embodiments that, as such, do not belong to the claimed invention. The reactor can generally comprise a catalytic layer 56 arranged on a support 54. As previously referred to Fig.As described in Figure 3, the catalytic layer 56 can generally accelerate the combustion reaction. For example, in the case of a hydrocarbon fuel, the catalytic layer 56 can accelerate the reactions of carbon monoxide and hydrocarbons to lower the temperatures required for the reaction, which in turn can lead to fewer emissions. When the fuel-air mixture 59 flows through the reactor 14, it can pass over the catalytic layer 56 and combust to produce exhaust gases. The fuel-air mixture 59 can contain various types of fuel, such as hydrocarbon fuels, non-hydrocarbon fuels (i.e., process gas, refinery gas, synthesis gas, etc.), and mixtures thereof.

[0040] During certain combustion periods, such as start-up after installation, particles and / or contaminants can be transported to the catalytic reactor 14 in higher concentrations. These contaminants can become trapped or adhere to the surface of the catalyst 56, thereby fouling the catalytic reactor and reducing its effectiveness. A sacrificial layer 58 can therefore be arranged as a protective layer over the catalyst 56, thus protecting it during these operating periods. The sacrificial layer 58 can be arranged, for example, during the initial commissioning of the turbine or after the replacement of certain equipment components such as the air compressor or the fuel supply system.In certain embodiments, the manufacturer can supply the catalytic reactor 14 with the sacrificial layer 58 already applied, so that it can be used when starting up the combustion chamber. In other embodiments, however, the sacrificial layer 58 can be applied after the catalytic reactor 14 has been installed in a combustion chamber, e.g., before starting up the gas turbine 12, when the gas turbine 12 is switched off or out of operation (e.g., while no combustion is taking place in the combustion section 20), or in any combination thereof. Furthermore, the sacrificial layer 58 can be applied as one or more layers or strata over the catalytic layer 56, each layer 58 being identical to or different from the other sacrificial layers 58 (e.g., using the same or different sacrificial materials, the same or different stripping mechanisms, etc.).In certain embodiments, one or more sacrificial layers 58 can be applied using a brush, a sponge, a material application device, a spray gun (e.g., a compressed air spray gun or an electrostatic spray gun), a liquid bath (e.g., a dip coating), flat elements mounted above the catalytic layer 56, or any combination thereof. The sacrificial layers 58 can therefore be applied as a liquid, vapor, solid, suspension (e.g., a solid dispersed in a liquid) such as a green suspension, as a gel such as a sol-gel, as vapor, as a spray conveyed in a gas (e.g., air, nitrogen, or another inert gas), or in any other suitable form.

[0041] The sacrificial layer 58 can generally prevent damage to the catalyst 56 by providing a protective layer over it. In certain embodiments, the sacrificial layer 58 can establish a physical bond with the catalyst 56. The sacrificial layer 58 can be a suitable tearable (e.g., easily ruptured) layer that can be chemically, mechanically, or thermally removed while the reactor is installed in the combustion chamber. For example, the layer can be chemically removed using a simple solvent such as water, alcohol, ethanol, ethylene glycol, degreasers, cleaning agents, or similar substances without harming the combustion process or the turbine materials. The layer can also be mechanically removed by applying mechanical forces, including, but not limited to, ultrasonic vibrations, pressure waves, and mechanical impact.For example, walnut shells can be passed through the catalytic reactor 14 to break up the sacrificial layer 58. The fragments of the sacrificial layer 58 can then be flushed out of the reactor 14, for example, during a compressor cleaning cycle. As another example, the gas turbine 12 can have a control mode with instructions for generating combustion dynamics in the combustion section 20, thereby generating or amplifying the combustion dynamics (e.g., pressure waves and consequently vibrations) to remove the sacrificial layer 58. The gas turbine 12 can also have a control mode with instructions for generating sound waves by controlling one or more loudspeakers or detonation wave sound horns, or with instructions for generating pressure waves by controlling one or more combustion-driven devices.Regardless of the stripping method, the sacrificial layer 58 can generally be removed without damaging the underlying catalyst 56. Furthermore, the sacrificial layer 58 can be removed without disassembling the combustion chamber components.

[0042] In certain embodiments, the sacrificial layer 58 can be arranged on other sections of the catalytic reactor 14 in addition to the catalyst 56. For example, the sacrificial layer 58 can be applied to parts of the flame tube 48, thereby providing a thermal barrier during start-up or other operations. The sacrificial layer 58 can be removed from other sections of the reactor 14 during the removal of the sacrificial layer 58 from the catalyst 56.

[0043] The sacrificial layer 58 (and each of the sacrificial layers disclosed herein) may contain any suitable layer type, for example, an inorganic oxide, a silicate, an inorganic halide, a metal nitrate, a metal chlorate, a metal acetate, a metal sulfate, a metal hydroxide, an organometallic compound, an organic-inorganic mixed oxide composition, a halogenated carbon compound, a combination thereof, or any other rupturable layer that can be removed chemically, mechanically, and / or thermally. An inorganic oxide layer may, for example, contain combinations of calcium and oxygen, such as calcium oxide (CaO), which can be removed using a water-based solvent, or nickel oxide (NiO), which can be removed using a hydroxide-based solvent.In another example, an organic layer can be used to form an oxygen barrier that can be removed during oxidation or thermally volatilized. In certain embodiments, the sacrificial layer 58 can contain bismuth subsalicylate, such as Pepto-Bismol®, commercially available from Procter and Gamble, Cincinnati, Ohio, or polytetrafluoroethylene (PTFE), such as Teflon®, commercially available from DuPont, Wilmington, Delaware. In some embodiments, the sacrificial layer 58 can contain milk of magnesia, magnesium hydroxide, or bismuth subsalicylate solutions. In certain embodiments, the sacrificial layer 58 can consist of relatively stable and environmentally friendly compounds to mitigate environmental concerns during removal of the sacrificial layer 58. The sacrificial layers 58 can also be in the form of a liquid, vapor, solid, or suspension (e.g.,The sacrificial layers 58 can be applied in various forms, such as a solid dispersed in a liquid (e.g., a green suspension), as a gel (e.g., a sol-gel), as vapor, as a spray carried in a gas (e.g., air, nitrogen, or another inert gas), or in any other suitable form. Consequently, the sacrificial layers 58 can be applied using various application devices, such as a brush, a sponge, a fabric applicator, a spray gun (e.g., a pneumatic or electrostatic spray gun), a liquid bath (e.g., dip coating), or any combination thereof. The sacrificial layers 58 can also be applied as planar elements that are mounted over the catalytic layer 56, e.g., with an adhesive, fasteners, or other mounting material.Table 1 below lists some, but not all, of potentially suitable sacrificial materials that may be used alone or together in various combinations as one or more sacrificial layers (and each of the sacrificial layers disclosed herein). Table 1: Examples of suitable operable layer materials Class material Green Suspension Sol-Gel - Application Single layer Two-layer base layer Two-layer coating, HT, top water soluble Rapid degradation at T>Tcd+100°F Oxide+Org. Al2O3+Zr2O3+NaPO4+Sugar J nz J J J J N Oxide+Org. High molecular weight surfactant polymer + ceramic powder (CaO, SiC etc.) J nz J J J J N silicate Si-C J J J nz J N N silicate MoSi2 J J J nz J N N Silicate / Oxide Slip-cast clay / porcelain J J J J J N N oxide Mullite J J J n. J N N oxide Barium titanate (Ba- J J J n. J N N oxide SrTiO3 J J J n. J N N oxide Al2O3 J J J n. J N N oxide Gel aluminide J J J n. J N N oxide thermal insulation layer J J J n. J N N oxide Zr2O3 J J J n. J N N oxide Fe2O3 J J n. J N N oxide CaO J J J n. J N N oxide Nickel oxide (NiO) J J J J J N N Ion compound Phosphate / Aluminum oxide J J J J J J N Ion compound (NH4) y Xz J J J nz J J Ion compound Nay Xz J J J nz J J Ion compound Ky Xz J J J nz J J Ion compound Metal compound of NO3 - J J J nz J J Ion compound Metal compound of ClO3 - J J J nz J J Ion compound Metal compound of CH3COO - J J J nz J J Ion compound Metal compounds of SO4 2- :FeSO4, MgSO4 J J J nz J J Ion compound MgOH J J J J J J N Crystalline organic DLC J N J Metallorg . Bismuth subsalicylate J J J N J J Nitride / Oxide hexagonal boron nitride (B2O3) J J J J J J N

[0044] In certain embodiments, the sacrificial layer 58 can acquire additional catalytic properties by using a layer based on magnesium, manganese, iron, nickel, or chromium. These catalytic properties can cause the sacrificial layer 58 to accelerate the combustion reaction when it is positioned on the catalyst 56. The sacrificial layer 58 can, for example, be applied before or during the initial commissioning of the gas turbine 12 ( Fig.1) arranged on the catalyst 56. In certain embodiments, the sacrificial layer 58 can be applied to the catalyst 56 before the gas turbine 12 is installed, while the gas turbine 12 is switched off or out of operation (e.g., while no combustion is taking place), during maintenance or repair work on the gas turbine 12, or in any combination thereof. As shown in Fig.As shown in Figure 4, the sacrificial layer 58 can be arranged above the catalyst so that the combustion gases 52 are unable to contact the catalyst 56. However, it is possible for the combustion gases 52 to contact the sacrificial layer 58, and the catalytic properties of the sacrificial layer 58 can accelerate the combustion reaction, thereby reducing emissions, when the sacrificial layer 58 is arranged in the reactor 14. In other embodiments, the sacrificial layer 58 can be doped with a catalyst. For example, the sacrificial layer 58 can be doped with a platinum group metal, such as ruthenium, rhodium, palladium, osmium, iridium, and / or platinum, to enhance its catalytic properties. In other embodiments, other dopants with catalytic properties can be used in the sacrificial layer 58, such as iron, cobalt, and / or nickel.

[0045] As previously mentioned, the sacrificial layer 58 can be temporarily arranged over the catalyst to protect the catalyst during operating times when the catalyst may be susceptible to damage from contaminants and / or particles such as are commonly deposited during commissioning. Fig.Figure 5 presents an exemplary method 60, not in itself part of the invention, for the use of a sacrificial layer 58 in a catalytic reactor 14. The method can begin with the application (block 62) of the sacrificial layer to the catalyst. In certain embodiments, the sacrificial layer 58 can be applied by the manufacturer during the assembly of the catalytic reactor 14, during the assembly of the combustion chamber 20, during the assembly of the gas turbine 12, or during any other assembly operation before the gas turbine 12 is put into operation (or is shut down). The sacrificial layer 58 can, for example, be applied during initial installation or as part of a subsequent installation in the combustion chamber 30 above the catalytic reactor 14. However, the sacrificial layer 58 can also be applied to the catalytic reactor 14 after the gas turbine 12 has been installed and / or during operation, e.g.through an access opening in the combustion chamber 20, through an existing fluid system (e.g., fuel system, water or steam injection system, nitrogen injection system, etc.), or any other suitable method. For example, the sacrificial layer 58 can be sprayed onto the catalyst during assembly using a type of masking application, or it can be applied by spraying, coating, dipping, brushing, or coating using a meniscus, etc. In some embodiments, the sacrificial layer 58 can be applied in the form of a green suspension or a sol-gel, with a carrier medium used to transport the sacrificial layer. The carrier medium dries out, and a crystalline form of the sacrificial layer can be formed.The sacrificial layer 58 can be applied as a liquid, vapor, gel, suspension, solid, or any combination thereof, using various application devices, such as a brush, spray gun, or bath. During application, the sacrificial layer 58 can be applied to the catalyst 56 as well as other areas of the combustion chamber 30. Fig. 3) like the combustion chamber flame tube 48 ( Fig. 3) be applied. After application, a drying process or another post-application process may take place, and in certain embodiments, the gas turbine 12 may be used to supply heat to simplify these post-application processes.

[0046] After the application of the sacrificial layer 58, the process can continue with the operation (Block 64) of the combustion chamber 30 for a defined period. The length of this period can be based on various factors such as manufacturer recommendations, plant design, manufacturing-related considerations, and the like. For example, during the start-up of a gas turbine 12, the combustion chamber 30 can be operated for approximately 10 to 250 hours, and during all intermediate periods. In particular, the combustion chamber 30 can be operated for approximately 50 to 150 hours. During this period, loose particles and contaminants can flow through the gas turbine 12. In another example, after the replacement of a compressor 18, the combustion chamber 30 can be operated for approximately 200 hours.

[0047] After the specified period, the sacrificial layer 58 can be removed by one or more stripping methods (e.g., washing with water, thermal removal, chemical removal, removal by pressure waves, etc.) as described in Block 66. The stripping process can take place while the catalytic reactor 14 and the combustion chamber 30 are housed in the gas turbine 12. If the sacrificial layer 58 is water-soluble, it can be dissolved, for example, during a test of the compressor cleaning system by means of turbine cleaning with water. In another example, a cleaning agent or other simple solvent can be passed through the combustion chamber 30 to remove the sacrificial layer 58. In certain embodiments, after the use of a simple solvent other than water, a water wash can be performed to flush out any remaining solvent from the combustion chamber 30.In some embodiments, erosion, ultrasonic vibrations, or a gas pressure pulse (i.e., a shock wave, etc.) can be used at the combustion chamber 30 to destroy the sacrificial layer 58. The sacrificial layers 58 can be removed, for example, by mechanical vibrations and / or pressure waves, such as by applying sound waves from a sound horn or loudspeaker, or by applying pressure waves from a combustion-driven device. As another example, the sacrificial layers 58 can be removed by inducing combustion dynamics in the combustion chamber, thereby generating pressure waves and vibrations to assist in the detachment of the sacrificial layers 58 from the catalytic reactor 14. The sacrificial layers 58 can also be removed with heat, for example, by gradual thermal degradation of the sacrificial layer 58 over a limited period until it is completely removed.After removal by means of vibrations, heat, mechanical means and / or other removal, the fragments of the sacrificial layer 58 can be flushed with water from the combustion chamber 30 and the gas turbine 12.

[0048] It is often desirable for the sacrificial layer 58 to exhibit a variety of advantageous properties such as water solubility, high-temperature resistance, catalytic activity, and other characteristics. Applying multiple layers of sacrificial layers, as described in [reference], can be advantageous for this purpose. Fig.Figure 6 illustrates this embodiment. In this embodiment, two sacrificial layers are arranged on the catalytic reactor 14, each comprising a different material. The first sacrificial layer 58 is in direct contact with the catalyst 56. A second sacrificial layer 70 is arranged on top of the first sacrificial layer 58. The second sacrificial layer 70 may contact the fuel-air mixture 59. At least one of the sacrificial layers 58 and 70 may also contain at least a certain amount of catalytic material. In certain embodiments, the first and second sacrificial layers 58 and 70 can be removed by the same or different stripping methods, for example, one or more of the following: liquid washing (e.g., washing with water or solvent), abrasion, vibration, sound waves, pressure waves (e.g., loudspeaker, sound horn, or combustion), combustion dynamics, or thermal removal.

[0049] In some embodiments, the first sacrificial layer 58 may contain a water-soluble material, while the second sacrificial layer 70 contains a high-temperature-resistant material or coating. The second sacrificial layer 70 may, for example, be at least approximately 1.1 to 10 times, 1.2 to 5 times, or 1.3 to 3 times more temperature-resistant than the first sacrificial layer 58. As another example, the second sacrificial layer 70 may be at least 10 to 1000, 20 to 500, or 30 to 250 degrees Celsius more temperature-resistant than the first sacrificial layer 58. The high-temperature-resistant coating forming the second sacrificial layer 70 may protect the first sacrificial layer 58 if the ambient temperature, approximately specified by the TCD (temperature at compressor discharge), approaches the temperature limit of the first sacrificial layer 58.The first sacrificial layer 58 can, for example, be magnesium sulfate (MgSO4), which is water-soluble; the second sacrificial layer 70 can be magnesium oxide (MgO), which is less water-soluble than magnesium sulfate but more temperature-resistant. In certain embodiments, the second sacrificial layer 70 can be a thermally removable material, e.g., a material composition that thermally degrades over a specific period under the start-up conditions in the gas turbine 12, e.g., 10 to 1000, 20 to 500, or 30 to 250 hours. After the thermal degradation / removal of the second sacrificial layer 70, the first sacrificial layer 58 continues to effectively protect the catalyst 56 of the catalytic reactor 14. The first sacrificial layer 58 can then be washed off with water to expose the underlying catalyst 56.In other embodiments, the second sacrificial layer 70 can be removed by abrasion, vibrations, sound waves, pressure waves (e.g., from loudspeakers, sound horns, or combustion), or combustion dynamics. For example, the gas turbine 12 can be controlled such that combustion dynamics are generated or amplified in the combustion section 20, thereby amplifying pressure waves and vibrations to effect the removal of the second sacrificial layer 70 and / or the first sacrificial layer 58. Any remaining sacrificial layer 58 can be washed away with water.

[0050] To the in Fig.To obtain the layer arrangement shown in Figure 6, the first sacrificial layer 58 can be applied to the catalyst 56 by spraying, dipping, coating, brushing, other application methods, or a combination thereof. Depending on its properties, the thickness of the first sacrificial layer 58 can range from approximately 0.001 mm to 10 mm, 0.01 mm to 1 mm, or 0.05 mm to 0.3 mm. A drying period or other intervening process can take place before the application of the second sacrificial layer 70. Similarly, the second sacrificial layer 70 can be applied by spraying, dipping, coating, brushing, another application method, or a combination thereof. Depending on its properties, the thickness of the second sacrificial layer 70 can range from approximately 0.001 mm to 10 mm, 0.01 mm to 1 mm, or 0.05 mm to 0.3 mm.In certain embodiments, the first and second sacrificial layers 58 and 70 can have the same or different thicknesses, be made of the same or different materials, and be applied using the same or different methods (e.g., spraying, dipping, coating, or brushing). A second application process can be performed on the second sacrificial layer 70. After both sacrificial layers 58 and 70 are complete, the catalytic reactor 14 can be mounted on the combustion chamber 30. The combustion chamber 30 can then be operated for an initial period during which the sacrificial layers 58 and 70 can protect the catalyst 56 from particulate byproducts generated during the initial start-up of the turbine 12 or after the replacement of certain equipment components, such as the compressor 18 or the fuel supply system.

[0051] To expose the catalyst 56 in Fig.6. The second sacrificial layer 70 can be removed before the first sacrificial layer 58. The second sacrificial layer 70 can be removed, for example, by thermal degradation, while the first sacrificial layer can be washed off with water. In other embodiments, the second sacrificial layer 70 and the first sacrificial layer 58 can be removed simultaneously using one or more stripping methods. The simultaneous removal of the sacrificial layers 58 and 70 can be achieved by an abrasion process, a tearing process, another form of mechanical removal, or another method. The sacrificial layers 58 and 70 can be removed, for example, by simultaneously applying one, two, or more of the following methods: washing with water, vibration, sound waves, pressure waves, abrasion, heat, or any combination thereof. To remove all remaining particles of the sacrificial layers 58 and 70, a water wash can be performed.Sacrificial layers of highly porous ceramic can be removed, for example, using flash evaporation of water, since the hot gas at the compressor outlet comes into contact with the highly porous ceramic after water washing has taken place. Alternatively, the water washing may simply dissolve and remove remnants of the sacrificial layers 58 and 70 left over from a previous stripping step. The stripping process can be completed while the catalytic reactor 14 remains mounted on the combustion chamber 30. The combustion chamber 30 can then be operated for a second period in which the catalyst 56 is exposed to the fuel-air mixture 59. During the second period, the catalyst 56 can influence the combustion reaction dynamics such that the amount of NO is reduced. x Emissions are reduced. In the Fig.In the embodiment described in section 6, two sacrificial layers 58 and 70 are applied; however, any number of sacrificial layers can be applied.

[0052] In another, in Fig.In the embodiment shown in Figure 7, five sacrificial layers are arranged above the catalyst 56. The first sacrificial layer 58 can be in direct contact with the catalyst 56. The second sacrificial layer 70 can be arranged on top of the first sacrificial layer 58. A third sacrificial layer 72 can be arranged on top of the second sacrificial layer 70. A fourth sacrificial layer 74 can be arranged on top of the third sacrificial layer 72. Furthermore, a fifth sacrificial layer 76 can be arranged on top of the fourth sacrificial layer 74. The fifth sacrificial layer 76 can contact the fuel-air mixture 59. The layer arrangement of the sacrificial layers 58, 70, 72, 74, and 76 can offer several advantages within the catalytic reactor 14.For example, some sacrificial layers 58, 70, 72, 74, and 76 may be highly water-soluble, some may be high-temperature resistant, some may be catalytically active, some may be hygroscopic, and some may exhibit other advantageous chemical properties. The various sacrificial layers 58, 70, 72, 74, and 76 may also possess several physical properties that are beneficial in a layer arrangement. For example, some sacrificial layers 58, 70, 72, 74, and 76 may be clay-like and harden upon heat supplied by the gas turbine; some may be powdery; some may be crystalline; some may be foamy and essentially porous; some may be gel-like; and some may retain other physical properties. In the [reference] of... Fig.In the embodiment shown in Figure 7, the first sacrificial layer 58 can be water-soluble, for example, magnesium sulfate (MgSO4), nickel oxide (NiO), or magnesium hydroxide (MgOH2). The second sacrificial layer 70 can have high-temperature resistant properties, for example, magnesium oxide (MgO), barium titanate (BaTiO3), calcium oxide (CaO), or another temperature-resistant material. The third sacrificial layer 72 can be catalytically active, for example, manganese oxide (MnO), hematite (iron(III) oxide - Fe2O3), or another catalytically active material. The fourth sacrificial layer 74 can have a crystalline structure, and the fifth sacrificial layer 76 can be in powder form.

[0053] In certain embodiments, each of the sacrificial layers 58, 70, 72, 74, and 76 can be applied using the same or different application methods, including spraying (e.g., compressed air spraying, liquid-only spraying, electrostatic spraying, etc.), immersion in a bath (e.g., liquid bath, gel bath, suspension bath, etc.), coating (e.g., electroplating), and brushing (e.g., with a brush, sponge, or fabric applicator). Likewise, each of the sacrificial layers 58, 70, 72, 74, and 76 can be applied in the same or a different physical form, including: liquid, solid (e.g., powder or clay), gel (e.g., sol-gel), suspension (e.g., solid particles dispersed in a liquid such as water, for example, a green suspension), vapor, or any combination thereof.Each of the sacrificial layers 58, 70, 72, 74, and 76 may furthermore have the same or different properties, including, but not limited to: thickness, temperature resistance, water solubility, chemical solubility, chemical resistance, material composition, hardness, wear resistance, catalytic activity, or any combination thereof. The material composition of each of the sacrificial layers 58, 70, 72, 74, and 76 may, for example, include one or more of the following materials: an inorganic oxide, a silicate, an inorganic halide, a metal nitrate, a metal chlorate, a metal acetate, a metal sulfate, a metal hydroxide, an organometallic compound, an organic-inorganic mixed oxide composition, a halogenated carbon compound, a combination thereof, or any other rupturable layer that is chemically, mechanically, and / or thermally removable.The material composition of each of the sacrificial layers 58, 70, 72, 74, and 76 may further contain one or more of the material(s) listed in Table 1. Additionally, each of the sacrificial layers 58, 70, 72, 74, and 76 may be removed by the same or different stripping methods, including but not limited to: thermal removal (e.g., thermal degradation over a period of time), washing with water, washing with chemicals, erosion (e.g., walnuts or particles), or any combination thereof. These stripping methods may be used alone or in combination to remove each layer 58, 70, 72, 74, and 76, either alone or in any grouping of layers.In other words, the sacrificial layers 58, 70, 72, 74, and 76 can be removed one after the other using various stripping methods, or two, three, four, or five sacrificial layers can be removed simultaneously using one or more of these stripping methods. In various embodiments, any of the aforementioned application methods, physical forms, properties, and stripping methods can be used in various combinations for each of the sacrificial layers 58, 70, 72, 74, and 76. Furthermore, one or more of the aforementioned application methods, physical forms, and properties can be used to achieve a gradual change (e.g., progressively increasing, progressively decreasing, or a changing scheme) in the characteristics of the sacrificial layers 58, 70, 72, 74, and 76 from one layer to the next away from the catalyst 56.For example, the thickness, hardness, temperature resistance, wear resistance, catalytic properties, solubility in water or chemicals can gradually increase, decrease or change from one sacrificial layer to the next away from the catalyst 56.

[0054] The sacrificial layers 58, 70, 72, 74 and 76 can be applied sequentially before the installation of the catalytic reactor 14 in the combustion chamber 30 and / or before the installation of the combustion chamber 30 in the gas turbine 12. In the embodiment of Fig.7. The first sacrificial layer 58 can be applied to the catalyst 56, followed by the remaining layers 70, 72, 74, and 76. The first sacrificial layer 58 can be applied by dipping, spraying, brushing (e.g., with a brush, sponge, or fabric applicator), coating, or another application method. The sacrificial layer 58 can be applied using a sol-gel, a suspension (e.g., a green suspension), a liquid, or another suitable form. A post-application process (e.g., drying, heating, evaporation, curing, or similar) can be carried out, and then the second sacrificial layer 70 can be applied by dipping, spraying, brushing, coating, or another application method. After a post-application process (e.g.,After the second sacrificial layer 70 has been dried, heated, evaporated, cured, or similarly treated, the third sacrificial layer 72 can be applied over the second sacrificial layer 70. The third sacrificial layer 72 can be applied using any of the previously discussed application methods, followed by a post-application process (e.g., drying, heating, evaporating, curing, or similar). After the third sacrificial layer 72 has been applied, for example, an evaporation process, a heating process, or another process can be carried out. The fourth sacrificial layer 74 can be applied after the third sacrificial layer 72 has been completed. In a particular embodiment, the fourth sacrificial layer 74 can be applied using a form of thermal spraying. A post-application process (e.g., drying, heating, evaporating, curing, or similar) can be carried out.Drying, heating, evaporation, curing, or similar processes can be carried out, and then the fifth sacrificial layer 76 can be applied. A further post-application process (e.g., drying, heating, evaporation, curing, or similar) can be performed to complete the fifth sacrificial layer 76. All five sacrificial layers 58, 70, 72, 74, and 76 can undergo a final post-application treatment. Other processes or treatments can also be performed to produce the sacrificial layers 58, 70, 72, 74, and 76, after which the catalytic reactor 14, which contains the catalyst 56 and the five sacrificial layers 58, 70, 72, 74, and 76, can be mounted on the combustion chamber 30. The combustion chamber 30 can then be operated in the gas turbine 12 for an initial period during a start-up or preparation phase.During the first period, the sacrificial layers 58, 70, 72, 74, and 76 can protect the catalyst 56 from particles, deposited particles, or other contaminants. Depending on the system requirements, the first period can range from 10 to 500 hours, 50 to 300 hours, or 100 to 200 hours. The embodiment of... Fig. Figure 7 shows the use of five sacrificial layers 58, 70, 72, 74 and 76; however, more or fewer sacrificial layers can be applied.

[0055] After the first period, to expose the catalyst 56, which is in Fig.As shown in Figure 7, the five sacrificial layers 58, 70, 72, 74, and 76 are removed using at least one or more of the preceding stripping methods. Each layer can be removed individually, or several layers can be removed in a single operation. The stripping process can be performed before or after a water wash of the system. Stripping operations can include mechanical, chemical, and / or thermal forms of stripping that do not damage the catalyst 56 beneath the sacrificial layers 58, 70, 72, 74, and 76. All stripping operations can be performed while the catalytic reactor 14 is arranged in the combustion chamber. After the removal of most or all of the sacrificial layers 58, 70, 72, 74, and 76, a second combustion period can take place in which the catalyst 56 can be exposed to the fuel-air mixture 59. The presence of the catalyst 56 allows NO xEmissions from the combustion reaction are reduced.

[0056] Fig. Section 8 contains a method 90 for using one or more sacrificial layers on the catalyst 56 in the catalytic reactor 14. The in Fig.The illustrated method 90 for the use of multiple sacrificial layers is merely one possible embodiment and may in fact include additional or fewer steps than shown. Method 90 begins with the application of at least one sacrificial layer over the catalyst 56 of the catalytic reactor 14 (unit 92). As described in preceding embodiments, one, two, three, four, five, or more sacrificial layers (e.g., 1 to 100 sacrificial layers) may be arranged over the catalyst 56. The application method for each sacrificial layer may be different or the same. Application methods include spraying, brushing, dipping, coating, and other methods. Each sacrificial layer may be applied as a sol-gel, green suspension, or any liquid, vapor, solid, or suspension form.The sacrificial layers can be applied individually or simultaneously, and after each application a drying, evaporation, curing, heating, or other post-application process can take place.

[0057] Once the sacrificial layers have been completely applied, the catalytic reactor 14 can be installed in the combustion chamber 30 (unit 94). The combustion chamber 30 can then be operated in a gas turbine 12 (unit 96) for an initial combustion period. This initial combustion period can take place during the initial commissioning of the gas turbine 12, for example, the first start-up after manufacturing, maintenance, or other repairs, provided that the gas turbine 12 (or at least one or more of its components) has not yet operated in normal turbine 12 operation. Initial commissioning can occur, for example, after the installation, replacement, or repair of the combustion chamber 30 (or any of its components such as the flame tube, fuel nozzles, etc.), the compressor 18 (or any of its components such as the compressor blades), the fuel supply system, or any other piece of equipment.During these periods, particles, deposited particles, and other contaminants that may be particularly harmful to catalyst 56 can affect the catalytic reactor 14. The sacrificial layers (e.g., 58, 70, 72, 74, and / or 76) can protect the catalyst 56 of the catalytic reactor 14 during the first combustion period in the gas turbine 12 (unit 98). After the first combustion period, at least one sacrificial layer can be removed from the catalyst (unit 100). Removal can involve one or more of the following processes: erosion, thermal degradation, application of vibrations or pressure waves, washing with water, washing with chemicals, or a combination thereof, while the catalytic reactor 14 remains installed in the turbine 12. Several sacrificial layers can be removed simultaneously, or each sacrificial layer can be removed independently, one after the other.After the majority of each sacrificial layer has been removed, catalyst 56 can be exposed to the combustion reaction. Emissions from the combustion reaction can be reduced by catalyst 56 after the removal of the sacrificial layers (Block 102). Catalyst 56 influences the combustion reaction dynamics and can reduce the amount of NO produced by the reaction. x -Reduce emissions. Application and stripping processes are described in more detail in further embodiments.

[0058] Fig.Figure 9 shows a flowchart illustrating an exemplary process 120 for applying multiple sacrificial layers to the catalyst 56 of a catalytic reactor 14. The process 120 can begin with the application of a first sacrificial layer 58 over the catalyst 56 of the catalytic reactor 14 of combustion chamber 30 (block 122). In one embodiment, the first sacrificial layer 58 can be a water-soluble base layer, for example, nickel oxide (NiO) or boron trioxide (B₂O₃). The first sacrificial layer 58 can be applied using a spraying, brushing, dipping, coating, or other application method, or a combination thereof. After the application of the first sacrificial layer 58, a post-application process can take place, for example, drying, curing, heating, evaporation, or another post-application process.

[0059] The second sacrificial layer 70 can be applied over the first sacrificial layer 58 (block 124). In one embodiment, the second sacrificial layer 70 can be a high-temperature-resistant material, for example, molybdenum disilicide (MoSi₂) or zirconium(III) oxide (Zr₂O₃). The second sacrificial layer 70 can provide additional protection for the catalyst 56. The second sacrificial layer 70 can be applied using a suitable method and can be applied independently of the first sacrificial layer 58 or simultaneously with the first sacrificial layer 58. The second sacrificial layer 70 can be subjected to a post-application process (e.g., drying, curing, heating, or evaporation).

[0060] A third sacrificial layer 72 can be applied over the second sacrificial layer 70 (block 126). In one embodiment, the third sacrificial layer 72 can be catalytically active, for example, manganese oxide (MnO) or hematite (iron(III) oxide Fe₂O₃). By using a catalytically active third sacrificial layer 72, the combustion reaction can take place in a catalytic environment even though the catalyst 56 is covered. In this way, emissions from the combustion reaction can be further reduced while the catalyst 56 is protected from potential contamination. The third sacrificial layer 72 can be applied independently of or simultaneously with the first sacrificial layer 58 and the second sacrificial layer 70. Any suitable application method can be used, as discussed in detail above. Following a possible post-application process (e.g.,After drying, curing, heating, or evaporation, the catalytic reactor 14 can be assembled and installed in the combustion chamber 30 of the gas turbine 12 (unit 128). In the embodiment described by method 120, three sacrificial layers 58, 70, and 72 are arranged over the catalyst 56. However, method 120 can be used to apply any number of sacrificial layers (e.g., 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, or more) to the catalyst 56 before installing the catalytic reactor 14 in the combustion chamber 30.

[0061] Fig. Figure 10 is a flowchart illustrating an exemplary method 140 for operating a combustion system with a catalytic reactor 14 and several sacrificial layers according to certain embodiments. In the embodiment described by method 140, three sacrificial layers are arranged on the catalyst 56. As in method 120 of Fig.As described in Figure 9, several sacrificial layers can be applied to the catalyst 56 of the catalytic reactor 14 before the catalytic reactor 14 is installed in the combustion chamber 30 and / or before the combustion chamber 30 is installed in the gas turbine 12. After installation or assembly, the combustion chamber 30 can be operated with several sacrificial layers (e.g., 2, 3, 4, 5, or more) arranged above the catalyst 56 (Block 142). The catalyst 56 is protected during an initial combustion period by the first, second, and third sacrificial layers 58, 70, and 72 (Block 144). The initial combustion period can occur during the start-up of the gas turbine 12 or when components of the system 10 have been replaced, thereby transporting particles through the catalytic reactor 14. This start-up period can, for example, be the initial commissioning after the manufacture, maintenance, servicing, or replacement of parts in the gas turbine 12, e.g.,the combustion chamber 30 or its components. Otherwise, if no sacrificial layers are present, the particles could damage the catalyst 56. The sacrificial layers 58, 70, and 72 (or any number of sacrificial layers) are therefore arranged above the catalyst 56 to provide protection during the initial commissioning period when impurities could otherwise damage or prematurely degrade the catalyst. The first combustion period can range from approximately 10 to 500 hours, 50 to 300 hours, or 100 to 200 hours, depending on the system requirements. Once the amount of particles released into the catalytic reactor 14 has been sufficiently reduced, the third sacrificial layer 72 can be removed from the second sacrificial layer 70 in an initial stripping process (unit 146).

[0062] The first stripping process (Block 146) for removing a large portion of the third sacrificial layer 72 can be designed such that the catalyst 56, the first sacrificial layer 58, and the second sacrificial layer 70 on the catalytic reactor 14 generally remain intact. A variety of stripping methods are possible. The first stripping process (Block 146) can, for example, involve the application of heat (e.g., thermal degradation), chemical washing, vibration, or pressure waves to remove the third sacrificial layer 72. After the removal of the third sacrificial layer 72, the first and second sacrificial layers 58 and 70 can protect the catalyst 56 during a second combustion period (Block 148). The second sacrificial layer 70 can be removed from the first sacrificial layer 58 in a second stripping process (Block 150).The second sacrificial layer 70 can be removed simultaneously with the third sacrificial layer 72, immediately after the removal of the third sacrificial layer 72, or at any time after the removal of the third sacrificial layer 72. The second stripping process (Block 150) can involve thermal or time-based degradation, chemical washing (e.g., the same washing process as or a different washing process than for the third sacrificial layer 72), or another stripping process that may preserve the first sacrificial layer 58 and the catalyst 56. After the removal of the second sacrificial layer 70, the catalyst 56 can be protected by the first sacrificial layer 58 during a third combustion period (Block 152). The third combustion period can last for any suitable duration. At the end of the third combustion period, the first sacrificial layer 58 can be removed from the catalyst 56 by a third stripping process (Block 154).The third stripping process (Block 154) can, for example, involve a water wash of the system or a chemical wash, in which the first sacrificial layer 58 is dissolved while the catalyst 56 remains intact. The third stripping process (Block 154) can also remove residues of the second and third sacrificial layers 70 and 72. After the removal of the first sacrificial layer 58, the combustion chamber 30 can be operated with the exposed catalyst 56 to meet emission targets (Block 156). The gas turbine 12 can, for example, operate under normal operating conditions while the catalyst 56 reduces emissions, e.g., NO. x -Emissions, reduces.

[0063] This written description uses examples to disclose the invention, including its best embodiment, and to enable a person skilled in the art to apply the invention, including the manufacture and use of devices or systems and the performance of the methods contained therein. The patentable scope of the invention is defined by the claims and may include further examples that a person skilled in the art might think of. These further examples shall fall within the scope of the claims if they have structural elements that do not deviate from the exact wording of the claims or if they include equivalent structural elements with insignificant differences from the exact wording of the claims.

Claims

[1] System, encompassing: a catalytic reactor (14) configured to be mounted on a combustion chamber (30), the catalytic reactor (14) comprising: a catalyst (56) designed to reduce emissions associated with combustion in the combustion chamber (30); a first sacrificial layer (58) which was arranged above the catalyst (56) in the combustion chamber (30) prior to the installation of the catalytic reactor (14); and a second sacrificial layer (70) which was arranged above the first sacrificial layer (58) prior to the assembly of the catalytic reactor (14) on the combustion chamber (30), wherein the first and the second sacrificial layer (58, 70) differ from each other, wherein the second sacrificial layer (70) has a higher temperature resistance than the first sacrificial layer (58); wherein the first and second sacrificial layers (58, 70) are removable, while the catalytic reactor (14) is mounted on the combustion chamber (30) without damaging the catalyst (56). [2] System according to claim 1, comprising a third sacrificial layer (72) arranged above the second sacrificial layer (70) prior to the assembly of the catalytic reactor (14) on the combustion chamber (30), wherein the second and third sacrificial layers (70, 72) are different from each other, wherein the first, second and third sacrificial layers (58, 70, 72) are removable while the catalytic reactor (14) is mounted on the combustion chamber (30) without damaging the catalyst (56). [3] System according to claim 1, wherein the second sacrificial layer (70) is degradable over time under the influence of temperature and the first sacrificial layer (58) is water-soluble. [4] System according to claim 3, comprising a third sacrificial layer (72) arranged above the second sacrificial layer (70) prior to the assembly of the catalytic reactor (14) on the combustion chamber (30), wherein the first, second and third sacrificial layers (58, 70, 72) are removable while the catalytic reactor (14) is mounted on the combustion chamber (30) without damaging the catalyst (56), wherein the third sacrificial layer (72) contains a catalytic material. [5] System according to claim 1, comprising a second sacrificial layer (70) arranged above the first sacrificial layer (58) and a third sacrificial layer (72) arranged above the second sacrificial layer (72), wherein the first, second and / or third sacrificial layer (58, 70, 72) is water-soluble, wherein the first, second and / or third sacrificial layer (58, 70, 72) contains a catalytic material. [6] System according to claim 1, wherein the first sacrificial layer (58) contains at least one material from the following: an inorganic oxide, a silicate, an inorganic halide, a metal nitrate, a metal chlorate, a metal acetate, a metal sulfate, a metal hydroxide, an organometallic compound, an organic-inorganic mixed oxide composition, a halogenated carbon compound or a combination thereof and / or an unfired ceramic. [7] System according to one of the preceding claims, comprising a gas turbine (12) having the combustion chamber (30) with the catalytic reactor (14). [8] Procedures, comprehensive: Application of a first sacrificial layer (58) over a catalyst (56) of a catalytic reactor (14); Applying a second sacrificial layer (70) over the first sacrificial layer (58), wherein the first and the second sacrificial layers (58, 70) differ from each other, the second sacrificial layer (70) having a higher temperature resistance than the first sacrificial layer (58); and Mounting the catalytic reactor (14) on a combustion chamber (30) after applying the first and second sacrificial layers (58, 70), wherein the first and second sacrificial layers are removable while the catalytic reactor (14) is mounted on the combustion chamber (30) without damaging the catalyst (56). [9] Procedures, comprehensive: Protecting a catalyst (56) of a catalytic reactor (14) mounted on a combustion chamber (30) with at least one first sacrificial layer (58) applied over the catalyst (56) and a second sacrificial layer (70) applied over the first sacrificial layer (58) during a first combustion period in the combustion chamber (30), wherein the first and second sacrificial layers (58, 70) differ from each other, the second sacrificial layer (70) having a higher temperature resistance than the first sacrificial layer (58); and Reducing emissions with the catalyst (14) during a second combustion period after the first combustion period in the combustion chamber (30), wherein at least the second sacrificial layer (58, 70) is removed from the catalyst (56) after the first period and before a second period, while the catalytic reactor (14) remains mounted on the combustion chamber (30).

Images