System and method for conversion of simple cycle system treatment of industrial gas turbine exhaust gas

Abstract

Methods and systems for providing a simple cycle (SC) system using gas with emissions control components with capability of later constructing a combined cycle (CC) system that includes HRSG components in conjunction with the emission control components of SC system. In one aspect discharge structure housing initially has a flow path with cavities capable of housing HRSG components and a housing roof overlying the cavities, so that after conversion to CC begins roof sections can be removed and HRSG components installed in the cavities with roof sections covering. In another aspect the discharge structure provides areas of space to install HRSG components, bypass conduits for exhaust flow and plates to block flow through the bypassed areas while SC operation continues, so that after HRSG components are installed blocking plates and bypass conduits are removed with CC operation of the converted system.

Description

SYSTEM AND METHOD FOR CONVERSION OF SIMPLE CYCLE SYSTEM TREATMENT OF INDUSTRIAL GAS TURBINE EXHAUST GASCROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to US Provisional Appl. No. 63 / 657,082 filed June 6, 2024, which is incorporated herein by reference.STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

[0002] Not Applicable.BACKGROUND OF THE DISCLOSURE

[0003] This application relates to systems and methods for treating industrial process gas turbine exhaust gasses. Such exhaust typically include one or more harmful substances such as carbon monoxide and / or nitrogen oxide. Such hot exhaust gas streams can include carbon monoxide, nitrogen oxides, and / or other exhaust gases. Chemical production, hydrocarbon cracking, steel production, and other processes similarly generate a hot exhaust gas stream including harmful substances. Typically, an exhaust gas stream is treated with one or more catalysts (e.g., in a catalyst bed) to mitigate carbon monoxide, nitrogen dioxide, and / or other substances. For example, catalysts can be used to convert nitrogen dioxide and / or carbon monoxide to one or more of water, diatomic nitrogen, carbon dioxide, and / or other less harmful compounds. To treat nitrogen oxides using a catalyst, typically a reactant is used such as anhydrous ammonia or an aqueous solution of ammonia that is introduced upstream of a selective catalytic reaction (SCR) catalyst.

[0004] Each catalyst and / or reactant has an operating temperature range that optimizes the desired reaction to mitigate components of the exhaust gas. Additionally, the catalyst or reactant itself and / or the housing (e.g., SCR) or material containing the catalyst and / or reactant can be damaged if the temperature of the exhaust gas exceeds the mechanical / chemical design limits for the catalyst or housing. Therefore, it is sometimes advantageous to controllably reduce the temperature of the exhaust gas prior to passing the exhaust gas into the catalyst materials such that the exhaust gas is within a temperature range for optimum treatment of certain components within the exhaust gas.

[0005] Many existing exhaust gas cooling systems and exhaust treatment systems suffer from inferior performance, limited operational flexibility, lifespan, efficiency and the like due to the limitations of cooling systems and the requirements of the exhaust treatment systems described above.

[0006] Power plants are very complex, incorporating many systems to ensure efficient, productive performance. Boilers and / or Heat Recovery Steam Generators (HRSGs) form the heart of the power plant and are engineered for a specified range of intended operational conditions. This range can be very broad but once defined, operation outside of these conditions can cause operational issues or even safety issues.

[0007] Typical combined cycle power plants include a power cycle using a gas turbine (GT), which discharges into a Heat Recovery Steam Generator (HRSG). An HRSG includes a plurality of heat exchangers. The heat exchangers can be of any suitable type including supported tube fields in the gas stream, one or more of shell and tube heat exchangers, double pipe heat exchangers, plate heat exchangers, or any other suitable heat exchanger known to one of ordinary skill in the art. HRSGs can include a high pressure evaporator heat exchanger positioned and supported in a housing. Other equipment can be positioned both upstream of, for example, high pressure superheaters and reheaters and between the high pressure evaporator heat exchanger and an exhaust stack, such as for example, high pressure economizer(s); intermediate pressure operating systems and / or low pressure operating systems each with their own superheaters, evaporators, economizers, etc.; preheaters; and / or other equipment. An example of a heat recovery steam generator system and such equipment is the heat recovery steam generator system described in U.S. Pat. No. 6,508,206, the entirety of which is hereby incorporated by reference, and the heat recovery steam generator system described in U.S. Pat. No. 10,180,086, the entirety of which is hereby incorporated by reference. HRSGs can include evaporators that can be connected by piping, tubes, ducting, or the like to be in fluid communication with a steam drum, such as disclosed in said U.S. Pat. No. 6,508,206, and U.S. Pat. No. 10,180,086 The high pressure components can contain high pressure or superheated steam which can be directed for other purposes such as driving a steam turbine.

[0008] As used herein, the term “fluid communication” should be understood to mean, unless expressly described otherwise, that two components in fluid communication are capable of receiving a fluid between them in unidirectional or bidirectional fashioneither directly or through intermediate components, with fluid passing through, for example, a conduit, tube, pipe, duct, or the like.

[0009] In traditional combined cycles, desuperheaters can be employed to elevate desuperheating water flow to be introduced into the steam network in an attempt to ensure that design temperatures are not exceeded. At lower gas turbine conditions, there exists a point at which additional desuperheater water cannot be added due to the desuperheater effluent encroaching upon the saturation temperature of the steam (i.e., additional water will not evaporate in the system). The use of desuperheaters and reheaters with HRSGs are illustrated in U.S. Patent No. 8,820,078 and U.S. Patent No. 9,435,228, both of which are incorporated by reference as if fully set forth herein.

[0010] HRSGs have employed selective catalytic reduction (SCR) systems such as shown and described in U.S. Patent No. 8,734,745, and U.S. Patent No. 11 ,668,219, both of which are incorporated by reference as if fully set forth herein. Patent No. 8,734,745 describes a combination of an ammonia vaporization assembly upstream of an SCR system. In that Patent No., 8,734,745 there is disclosed an ammonia vaporization system 32 having an ammonia injection grid 40 configured to inject ammonia vapor into the exhaust gas discharge stream within an HRSG casing so that the ammonia vapor interacts with a selective catalytic reduction system located downstream of the ammonia injection grid 40 and within the HRSG casing 22 exhaust flow path. HRSGs can also employ duct burner assemblies which use supplementary firing to increase the heat energy of a gas burning exhaust, making it possible to increase the output of downstream heat recovery, an example of which is shown and described in U.S. Patent No. 9,909,462, which is incorporated by reference as if fully set forth herein.

[0011] The combined cycle (CC) unit can also include “cogeneration” (a.k.a. “combined heat & power” or CHP, within this document also referred to as Heat Recovery(HR)) employing the use of a portion or all of the generated steam or other heated fluid in a process or other use outside of the generation of electricity.

[0012] Fig. 1 is a sectional view of a system with housing that is designed to accommodate future components of a heat recovery steam generator (HRSG), which housing can be used in conjunction with a Simple Cycle gas turbine operation and later can be converted to a Combined Cycle operation;

[0013] Fig. 2 is a top plan view of system with housing of Figure 1 ;

[0014] Fig. 3 is a sectional view of a system with housing after the system and housing of Figures 1 and 2 has been converted from a Simple Cycle system to a Combined Cycle system;

[0015] Fig. 4 is a top plan view of the converted system with housing of Figure 3;

[0016] Fig. 5 is a partial section view of a system and housing which can operate in conjunction with a Simple Cycle gas turbine operation through a bypass arrangement, and is designed to accommodate future components of a heat recovery steam generator (HRSG) to be converted to a Combined Cycle operation;

[0017] Fig. 6 is a top plan view of the system and housing of Figure 5, showing bypass conduits and open areas for future installation of HRSG components;

[0018] Fig. 7 is a modified system and housing top plan view showing a different bypass conduit arrangement from Fig. 6, with open areas for future installation of HRSG components;

[0019] Fig. 8 is a partial section view of a system and housing of Fig. 5 after installation of HRSG components and conversion to a Combined Cycle operation;

[0020] Fig. 9 includes a schematic of a cooling coil of a heat exchanger and a selective catalytic components for use in conjunction with the systems and methods of the disclosure, wherein the temperature of flue gas exiting exchanger 408 is in the correct temperature range for the catalyst beds;

[0021] Fig. 10 is a schematic representation from U.S. Patent No. 11 ,668,219 related to Figure 9;

[0022] Fig. 11 is a top plan view of systems and housings of the disclosure after installation of HRSG components to convert to Combined Cycle operation, showing roof sections with installed pipes and grasping I-beams;

[0023] Figure 12 is an isometric drawing of a housing with three dimensional illustrations of an alternate arrangement for the bypass conduits;

[0024] Figure 13 is an isometric drawing of a housing with three dimensional illustrations of roof sections of HRSG housing after conversion from Simple Cycle to Combined Cycle operation, illustrating location of I-beams and various pipes extending upwardly therefrom;

[0025] Figure 14 is a schematic illustration of the layout of a “shop modular” alternate two module wide flow path system for flow through HRSG components;.

[0026] Figure 15 is a schematic illustration of the layout of a “shop modular” alternate three module wide flow path system for flow through HRSG components; and

[0027] Figure 16 is a schematic illustration of the layout of a four module wide “shop modular” alternate style system for flow through HRSG components.

[0028] Corresponding reference numerals indicate corresponding parts throughout the several figures of the drawings.SUMMARY OF THE PRESENT DISCLOSURE AND DESCRIPTION OF DISCLOSURE

[0029] In this disclosure, terms such as HRSG, SC, CC, CHP, HR, etc. are intended represent and / or include any heat recovery unit and / or associated equipment in any gas turbine exhaust path for power production, heat recovery for process / CHP, etc. Terms such as power plant, etc. are also intended to include other configurations such as CHP, CC / cogeneration, etc. The present disclosure is related to the gas path of the gas turbine exhaust from the turbine scope outlet through the main exhaust stack. In a combined cycle plant this path is commonly referred to as the aforementioned Heat Recovery Steam Generator (HRSG).

[0030] This present disclosure describes methods to minimize the conversion time and cost required to convert a Simple (a.k.a. open) Cycle (SC) unit with the appropriate initial setup into a gas turbine heat recovery unit, for example a Combined Cycle (CC) unit. While for the SC unit the incorporation of additional components and increased process conditions / constraints of a CC may increase the initial cost of the SC unit, the total installed costs of the ultimate CC unit can be greatly reduced. The “CC unit” as used herein can be or include any heat recovery unit in the gas turbine exhaust path. The methods can also maximize component reuse through the conversion process. For example, all the ducting / casing and gas side expansion joints can be designed for and with materials selected based on the maximum design pressure and temperature required for the controlling case of the SC and CC cases. For example, the TEG design pressure can be very different for a SC unit versus a CC unit with the CC typically being significantly higher. Another example is that ductwork / casing and gas side expansion joint(s) areas downstream of the SCR catalyst will likely rely on the SC design to set required insulation thickness and liner material due to the CC heating surfaces being installed at the SC / CC conversion. Other examples include removable roof casings in the heating surface bundle installation areas for the SC-CC conversion.The removable roof plugs can be installed as “welded” (and cut them out) or as bolted design. The new roof panels could come shop installed on the heating surface bundles to be dropped / set in with the bundle during installation and welded in place as known in the art, though other designs known in the art would certainly be operable and intended to be incorporated herein. Another positive impact of the present disclosure is a significant reduction in greenhouse gases per electrical and / or thermal unit of overall plant output / production resulting from the SC-CC conversion due to the much greater thermodynamic efficiency of the equipment in CC (current units can exceed 60%) relative to the SC (currently gas turbines can exceed 45%).The "foundation layout” is a term used herein to express changes required to the “HRSG” configuration to achieve the offered reduction in conversion time from SC to CC (this relies on the heating surface design being complete and fixed when designing the SC to CC unit).

[0031] A Simple Cycle (SC) as referred to herein is meant as a gas turbine generator operating in Brayton cycle typically with emissions control and necessary “turbine exhaust gas” (“TEG”) temperature control for proper operation of the emission control devices. Combined Cycle (CC) as used herein means gas turbine generator operating in Brayton cycle with heat recovery operating in Rankine cycle to raise steam for expansion in a steam turbine to make electricity, electricity out both ends of the cycles, and typically employ emissions control devices located in the appropriate temperature window(s). The use of “CC” in this disclosure is intended to include any type of heat recovery unit (CC, CC+HR, CHP, etc.) in the gas turbine exhaust path with and without appurtenances.

[0032] The disclosure herein introduces methods to minimize the time required to convert a Simple (a.k.a. open) Cycle (SC) unit with the appropriate initial setup into a combined cycle unit. The disclosed system can have a combined cycle / cogeneration system that includes features of each. The disclosure also can maximize reuse of installed SC equipment in the conversion to CC while eliminating the large tempering air fans and the additional air flow associated with the traditional SC design. There are two main scenarios disclosed, with which this can be associated. The first considers accomplishing the conversion while the SC plant is operating, the second requires ceasing operation of the SC during the conversion. The new prearrangements make it possible to reduce or minimize the time required to convert a properly configured SC operation into a Combined Cycle (CC) and / or other Heat Recovery (HR) (e.g., cogeneration, combined heat & power (CHP)) operation.

[0033] Also, equipment that is not needed in the CC unit after the SC / CC conversion is complete (i.e., mostly this will be equipment outside the casing in Figure 9 where component 408 represents heating surface inside the casing / setting) can be modularized (e.g., air-cooled heat exchanger ACHX) and used for other projects.

[0034] The new prearrangements provide that the CC and / or HR design of the heat exchange surface can be detailed such that the foundation design, loads, etc. can be set. This relies on the heating surface, TEG flow and temperature distributions and required straightening device(s), and emissions equipment designs being complete and fixed. Changes that could be required include but are not limited to setting the local casing / ducting insulation thickness per the simple cycle requirement rather than the ultimate CC and / or HR requirement and similarly reviewing the stack diameter requirements. It could be that the same stack flow area can be used for both the SC and CC operation. This must be verified case-by-case. In addition, when applied as envisioned the SC-CC unit can be capable to reuse the heating surface, oxidation (CO) catalyst and the selective catalytic reduction (SCR) catalyst along with the ammonia injection grid and external ammonia evaporation and injection skid, stack silencing, stack dampers, the stack itself, also TEG flow straightening device(s), etc. in both the SC and CC modes. For example, regarding stack reuse the stack TEG velocity will be very different between SC and CC so the environmental permitting may need to consider this to be used for both cases. The stack may also require internal insulation (ID can be made the same) or the upgrading of material for the SC case. It is also possible to replace any component with a version suitable for CC operation when that is required. Where capable, equipment (mainly external to the HRSG casing) designed for the SC design can be used elsewhere in the CC plant or moved to another SC-to-CC conversion project (for example the air-cooled heat exchanger for heat rejection).

[0035] Alternative Version 1 is shown in Figures 1 - 4. It is intended for a client and site that is unsure at the time of constructing the SC whether, or when, conversion from SC to CC and / or HR will happen or not yet still desire to minimize the operating disruption by minimizing the gas turbine down time required fortheir conversion should it occur. Bypasses are not installed so the gas turbine must be shut down for the entire conversion. The SC cannot operate during the conversion to CC and / or HR. All casing, foundations, catalyst, potentially heat transfer surface and exhaust stack should be available for reuse since it was designed for the potential addition of a futureCC. Conversion time savings will be significant compared to full CC installation time later, and the gas turbine outage or down time can be less as well.

[0036] Alternative Version 2 is shown in Figures 5-8 It is intended for a site for which it is known or suspected that conversion from SC to CC and / or HR is coming and there is desire to minimize the operating disruption by minimizing the gas turbine down time required for the conversion. Bypasses are employed to allow the Turbine Exhaust Gas (TEG) to be fully bypassed around the portion where the remainder of the combined cycle will be installed. When the conversion to the CC begins this allows the SC operation to continue while the CC and / or HR additional heat transfer surface installation is completed. After the structures for the conversion to the CC have been installed all that remains then is to block the bypasses and couple the gas path together at the particular locations in Figure 5-8. Conversion time savings can be very significant compared to full CC installation time later and the gas turbine outage time can be less as well. As presented here Alternate Version 2 (Figures 5-8) is one particular example of a potential arrangement. Many other bypass configurations exist as well and are incorporated herein. For example Figure 12:demonstrates multiple “bypass” ducts (e.g. flanged (or welded) pipes) which can also incorporate bringing the exhaust directly into the TEG path within a set of flow distribution lances and may also utilize balancing dampers / valves in each of the multitude of bypasses would allow tuning of the TEG mass flow distribution to the individual lances in cases wherein that is desired; similar to what is taught in US 2014 / 0044634 A1 , which published application matured into U.S. Patent No. 8,734,745; 2. Figure 12 is an isometric view of housing 23” showing C-shaped bypass conduits 322 with damper / valves 324 extending from roof section 64A” of housing 23”, such as provided by bypass conduit 222 and 222’ of the Figs 5 and 6 embodiments, respectively. Fig. 12 also shows bypass conduits 422 extending from the sidewall of the housing 23’ such as illustrated in Figures 5 and 6, with baffle / valves 328. Other multiple bypasses can be used to bring flow into a duct manifold that runs up the side and over top / bottom of the HRSG.

[0037] Figures 1-8 and 11-13 generally show HRSGs with multiple transverse heating surface bundles comprising a single flue gas exhaust path that would otherwise be too large to ship to site using conventional shipping methods. This single flue gas path is encased as described herein by a single generally field erected casing. Well known to those knowledgeable in the art, one method is to erect shop insulated floor and sidewall panels and roof beams into which heat transfer modules in parallel and inseries will be inserted, see especially Figures 11 and 13. This general method is discussed in greater detail herein as a basis to describe the general concepts. Figures 14-16 illustrate another possible ducting and casing style for construction of a HRSG. As previously mentioned there are many more which are all intended to be incorporated herein. Presented in Figures 14-16 for those knowledgeable in the art are schematic illustrations of, respectively, a two module wide (width transverse to the flue gas flow) system 100, a three module wide system 110 , and a four module wide “shop modular” style system 120. “Shop modular” is intended convey the concept that the casing box (roof, floor, and sidewalls) around each heat transfer module is applied in the shop and transported as an assembly that will generally be righted to vertical and lifted onto the appropriate portion of the HRSG foundation. Since there are multiple trains of heating surface the inlet ducting and outlet plenum to the stack are generally of the pant-leg style (so named for the original two module wide example) as indicated on the figures. The outlet can comprise a single gas path (exhaust stack) as shown on the figures or another alternative, one of which could be to have an individual exhaust flue to atmosphere on each module train.

[0038] A. The concept of designing a SC unit for future conversion to a CC requires forethought and includes the following basic steps. These steps are generalized and it is understood that any and all required details and sub steps within or due to each generalized step are included within:

[0039] 1. The site developer or responsible entity specifies the current SC requirements and the future CC requirements.[0040J2. The SC / CC equipment design / supply entity and the site developer or responsible entity define which Alternative Version 1 or 2 or where in between to set the level of bypassing or lack thereof to provide for the specific design. Determination of any external use for the heat recovered during SC operation, for example district heating requirements (as necessary) should also be determined at this stage.

[0041] 3. The SC / CC equipment design / supply entity designs the CC equipment with layout of the foundation details for the CC equipment.

[0042] 4. The SC / CC equipment design / supply entity designs the SC equipment including any specific modifications that will be required to convert to the CC design and foundations to accommodate the initially installed SC.

[0043] 5. The SC / CC equipment design / supply entity then merges the SC and CC design and foundation requirements into one foundation layout / design common to both the SC and CC designs.

[0044] B. The SC and CC designs referenced above also include steps which are generalized as including the following steps. These steps are generalized and it is understood that any and all required details and sub steps within or due to each generalized step are included within:

[0045] 1. The SC / CC equipment designer determines, or designs, the details of the ducting (open TEG flow path) and casing (ducting that has or will have heating surface contained within), heat recovery surfaces, catalyst system(s), duct burners, main exhaust stack, and any other subsystems, etc. as with any normal CC design including setting the foundation requirements for loads, movements, layout, etc. to meet the specified requirements of the CC.[0046J2. The SC / CC equipment designer defines the requirements for the CC catalyst beds and ammonia injection location maximum and minimum allowable TEG temperatures to achieve emissions compliance over the specified envelope of operating conditions defined by the site developer or responsible entity. These generally include for example requirements for the maximum stack exit levels of oxides of nitrogen (NOx), carbon monoxide (CO), ammonia slip (NH3), etc.

[0047] 3. The SC / CC equipment designer reviews the specified SC to CC conversion requirements including for example spaces for bypasses, gas path flow blockages, etc. for Alternate Version 1 , lack of these requirements for Alternate Version 2, or anywhere between these that the project requires.[0048J4. The SC / CC equipment designer selects required portion(s) of the CC surfaces(s) to control local TEG temperatures to the CO catalyst, AIG, SCR catalyst, and any other (typically emissions related) requirements for the SC operation. It is preferrable but not mandatory to use portion(s) of the surface that will be required eventually for the CC operation to maximize reuse of the SC required equipment. This is done so that the emissions control equipment can be reused after conversion to CC mode as well.

[0049] a. If necessary, design SC specific heating surface to achieve the desired temperatures noted above. Note that this option could require the removal of this SC specific heating surface during the SC to CC conversion adding undesirable time, person-hours, etc. to the conversion schedule. It may be preferable to let thesesurfaces remain in the gas path unused (i.e., running dry) if the materials of construction, etc. can survive the local TEG environment in the CO case.

[0050] b. It may be preferable to use an alternate working fluid for the SC operation if that is determined to benefit the SC mode operation. For example, carbon dioxide (CO2) could be used rather than water (as is typical for the CC operation) as a working fluid to remove heat from the system. CO2 has benefits and drawbacks and is not the only potential alternate working fluid. These could include H2O, CO2, various heat transfer fluids, various molten salts, various liquid and / or two-phase metals (e.g., Na, etc.), various glycol mixtures, saline solutions, etc. designed for freeze protection, etc. It is not the intention to limit the scope of applicability of the methods described here to any specific working fluid as each site, process, client, etc. can yield preferred fluids for their particular reason(s).

[0051] c. It may also be preferable to use all or a portion of the heat removed from the SC exhaust via the installed cooling loop (e.g., Figure 9) to be discharged to atmosphere, and used for process applications including, but not limited to, heating, cooling and drive operations. The energy can also be stored for later use.

[0052] 5. The SC / CC equipment designer determines how the arrangement of these bypasses, heating surfaces, etc. fit into the SC / CC setting. This could require Computational Fluid Dynamics (CFD) analyses on the flue gas side and / or working fluid side of the heating surfaces to determine for example spaces required for bypass flows entering or leaving the flue gas path, the design of TEG flow and / or temperature distribution enhancing devices / equipment and / or configuration(s), etc.[0053J6. The SC / CC equipment designer makes requisite modifications to the CC foundation layout, etc. to accommodate both the SC requirements and the CC requirements in the same foundation plan. This layout or another that satisfies both the SC and CC requirements may be used. It is not intended to limit the scope of applicability of these methods only to the most optimal arrangement but to cover any arrangement that fits requirements.

[0054] An advantage of conversion from SC to CC is the improvement in plant efficiency and heat rate associated with the addition of heat recovery to the base SC unit. In some cases, for example, the gas turbine can be delivered early such that operating the gas turbine in SC mode immediately and not waiting for the full CC to be completed can be an advantage for power generation and heat recovery that can potentially be used elsewhere. When this is the case the methods presented here canbe used to anticipate conversion of the SC to CO mode in the minimum amount of time. This is an example and not intended to limit the scope of applicability of these methods.

[0055] As can be understood from the above, an advantage is that the site can operate the gas turbine in simple cycle while the combined cycle is being built out. Once the CC is ready the conversion time is minimized and consists of decoupling the bypasses (if present), removing the TEG blocking plates in the main HRSG duct (if present), and buttoning up some piping, among other possible steps, which work is comparatively minimal.

[0056] Further embodiments of the cooling system described herein for Heat Recovery Steam Generators (HRSG) allow for an increased range of operation of the power plant while promoting higher power plant efficiency. In such power plants, as power demand decreases the gas turbine output is reduced. The reduction in the gas turbine power output results in a reduction in the hot exhaust gas flow from the turbine and in many cases an increase in the exhaust gas temperature, a decrease in TEG mass flow, or both into the HRSG. This in turn results in the HRSG performing off design and at lower efficiency. The cooling system of this disclosure provides a control coil at the entrance to the HRSG that is independent of the coils of the HRSG. The control coil can be run at any load (any adjusted rate of fluid flow through the coil) to remove required heat from the gas turbine exhaust entering the HRSG to reduce the exhaust gas temperature. This allows the HRSG to operate safely and efficiently behind the reduced power gas turbine. The heat recovered by the control coils may be directed to a thermal energy storage system (TESS) where the heat is stored until operations of the HRSG can make use of the stored heat energy to address peak load conditions or for other process needs. The inlet control coil works to control and limit the high heat of the gas turbine exhaust input into the HRSG. The control coil can then be controlled to allow the heating up of the HRSG by controllably reducing the rate of cooling fluid flow through the coils. The disclosure’s use of a dedicated heating surface coil (control coil), or set of such coils each individually designed, in which the flow through the coil(s) is independent of the steam production from the evaporator portion of the boiler. In contrast, with traditional coils, the steam flow passing through the superheater I reheater heating coils is dictated by the steam production in the dedicated evaporator section (s) of the HRSG / boiler.

[0057] The use of the controlling coil, through which a heating fluid, gas or supercritical fluid is passed, reduces, and can eliminate, the need for excessive desuperheating at low loads, while not suffering operation limits imposed by physical limits. For instance, the heat recovered by the supercritical fluid / heating fluid passing through the control coil may not even have a saturation temperature impact (i.e., working fluid could be single phase). Additionally, the heat recovered by the control coils may be directed to a thermal energy storage system so that there would be no need to temper the temperature of the fluid at the outlet of the HRSG controlled coils.

[0058] As used herein, the terms casing, ducting, casing / ducting sidewalls, casing / ducting floor, casing / ducting roof (also welded or bolted roof plug), are intended to include for example cold casing defined as an internally insulated outer casing plate with the insulation sometimes covered internally with a floating metal liner system. The “cold” outer plate forms the pressure boundary of the gas path for an HRSG.FURTHER DESCRIPTION OF DISCLOSURE

[0059] As used herein, the terms "turbine exhaust gas" should be understood to be gas from or related to any process such as combustion (e.g., related to power production), chemical production, oil cracking, steel production, or other process that uses or produces as a byproduct a turbine exhaust gas. Referring again to a simple cycle turbine facility, such facilities use only a singular thermodynamic cycle (e.g., Brayton cycle) employed such that the hot exhaust gases from the gas turbine are vented directly to the atmosphere. If emission reductions are required in a simple cycle plant, often large forced draft fans are used to mix large amounts of ambient air with the gas turbine exhaust to achieve the required catalysts operating temperatures. These fans are often expensive to procure and generally have high operating costs (e.g., electrical consumption is high).

[0060] This temperature control allows for improved treatment of the turbine exhaust gas. For example, typically the targeted optimum temperature range for the carbon monoxide treating catalysts does not overlap with the optimum temperature range for the nitrogen oxides treatment reactions. The temperatures for treating carbon monoxide are higher than the temperatures for treating nitrogen oxides. As a result, often the carbon monoxide treatment catalyst can operate in a hotter temperature range, below an upper limit, than the SCR catalyst. The use of multiplecooling coils (e.g., heat exchangers) allows for the temperature of the turbine exhaust gas stream to be controlled to improve the effectiveness of the catalytic treatment.

[0061] In some embodiments of the turbine exhaust gas treatment system, the system uses supercritical carbon dioxide as the working fluid. This provides some specific advantages in that supercritical carbon dioxide has a high fluid density making it easy to pump around a closed cooling loop and a high heat capacity such that the system can use a lower amount of fluid passing through the heat exchanger coil for the same temperature reduction of hot turbine exhaust gas. Other suitable heat transfer working fluids including, but not limited to, thermal oils and / or water can be utilized in other embodiments of the turbine exhaust gas treatment system.

[0062] Referring now to FIG. 1 , there is shown a housing that is designed to accommodate future components of a heat recovery steam generator (HRSG). However, such HRSG components are not present in Figure 1 for reasons discussed previously, i.e., the client , customer or owner has not decided to yet go to the expense of installing an HRSG but does desire to operate a Simple Cycle (SC) system at the present time. This design thus allows the client or owner to later install the desired HRSG components into the Figure 1 housing. As discussed earlier, the planning for the configuration of the housing and other components of the Fig. 1 is done in contemplation for fitting with HRSG components of a desired size and capabilities. As discussed earlier, such HRSGs are known in the art, such as disclosed in U.S. Pat. No. 6,508,206, and in U.S. Pat. No. 10,180,086, the entirety of both of those patents is hereby incorporated by reference as if fully set forth herein. The use of superheaters and reheaters with HRSGs are also illustrated in U.S. Patent No. 8,820,078 and U.S. Patent No. 9,435,228, both of which are incorporated by reference as if fully set forth herein. HRSGs have employed selective catalytic reduction (SCR) systems such as shown and described in U.S. Patent No. 8,734,745, and U.S. Patent No. 11 ,668,219, both of which are incorporated by reference as if fully set forth herein. HRSGs can also employ duct burner assemblies which use supplementary firing to increase the heat energy of a gas burning exhaust, making it possible to increase the output of downstream heat recovery, an example of which is shown and described in U.S. Patent No. 9,909,462, which is incorporated by reference as if fully set forth herein.

[0063] In the elevation view of Figure 1 is illustrated a simple cycle system 20 comprising a housing 23 with an upstream inlet 24 and an upstream end 26 that extends into an exhaust stack 29. An exhaust flow path 32 is formed within the housing23 for receiving industrial process turbine exhaust gas (TEG) which can flow through the housing to the upstream end 26 and out of the exhaust stack 29 into the ambient atmosphere. The system 20 is designed with the housing 23 having a first cavity 35 within the flow path 32 sized to accommodate the installation of potential HRSG components for a Combined Cycle (CC) system operation. Within the first cavity 35 is a coil (heating surface) of tubes 38 having upper and lower headers, return bends, or other mechanism so that fluid such as water or other suitable fluid can flow therethrough. The coil 38 is configured to operate from a flow of the fluid that is separate from the fluid flowing through any future HRSG components. In a completed unit, feedwater from later installed feedwater heaters could provide cooling effects of water. Downstream from cavity 35 is a second cavity 44 which houses catalytic turbine exhaust gas treatment devices. The devices include a first catalytic turbine exhaust gas treatment device 54 which is positioned downstream from the first cavity and downstream from the coil 38, so that turbine exhaust gas flow comes into contact with the catalytic exhaust gas treatment device 54. The catalytic exhaust gas treatment device 54 is adapted and configured to treat at least one component of the turbine exhaust gas through a catalytic reaction between a catalyst contained within the catalytic exhaust gas treatment device 54 and the at least one component of the turbine exhaust gas. For example, the catalytic exhaust gas treatment device 54 contains any suitable catalyst agent to catalyze the reaction of oxygen present in the TEG with carbon monoxide to form carbon dioxide. For example, carbon monoxide can be treated using platinum, rhodium, palladium, oxidizers generally, or any other suitable catalyst(s).

[0064] The housing cavity 35 can further include a second catalytic turbine exhaust gas treatment device 56 positioned downstream of the first catalytic device 54. The second catalytic turbine exhaust gas treatment device 56 is adapted and configured to treat at least one component of the turbine exhaust gas through a catalytic reaction between a catalyst contained within the second catalytic turbine exhaust gas treatment device 56 and the at least one component of the turbine exhaust gas. For example, the second catalytic exhaust gas treatment device 56 contains any suitable agent to react with nitrogen oxides to form one or more of water, diatomic nitrogen, or other compounds. The agent can be or include a second reactant such as anhydrous ammonia, an aqueous solution of ammonia, or the like as well as other component(s) found in the TEG. Aforementioned Patent No. 8,734,745 describes a combination of an ammonia vaporization assembly upstream of an SCR system. Patent No.8,734,745 describes an ammonia vaporization system 32 with an ammonia injection grid 40 that injects ammonia vapor into the exhaust gas discharge stream within the HRSG casing so that the ammonia vapor interacts with a selective catalytic reduction (SCR) system 26 located within the HRSG casing 22 downstream from the ammonia injection grid 40. In the present application the second catalytic turbine exhaust gas treatment device 56 comprises an ammonia injection grid 58 and a selective catalytic reduction (SCR) system 59 which correspond respectively to the ammonia injection grid 40 and SCR system 26 of Patent No. 8,734,745, The liquid flow through coil 38 acts to cool the turbine exhaust gas to the desired temperature for the catalytic devices 54 and 56 can function in the desired temperature range. As shown in the top plan view schematic of Fig. 2, the water discharged from the coil 38 can be directed though pipe 57 or flow communication device elsewhere such as to district heating, or to a thermal storage device, to utilize the heat that it has absorbed from the TEG, or the heat can be rejected such as in an air cooled heat exchanger.

[0065] In some embodiments, the first catalytic turbine exhaust gas treatment device 54 is adapted and configured to treat both carbon monoxide and nitrogen oxides within the turbine exhaust gas. The first catalytic turbine exhaust gas treatment device 54 can treat both carbon monoxide and nitrogen oxides using multiple catalysts or a single catalyst. For example, in the case of a single catalyst, the first catalytic turbine exhaust gas treatment device 54 can include iron and cobalt impregnated over activated semi-coke. The catalyst is fed with carbon monoxide (e.g., from the turbine exhaust gas) to absorb or otherwise remove nitrogen oxides from the turbine exhaust gas. Other single catalysts can be used to treat both carbon monoxide and nitrogen oxide such as a barium-promoted copper chromite catalyst or any other suitable catalyst.

[0066] With regard to the coil 38 and the aforementioned U.S. Patent No. 11 ,668,219, the operation of coil 38 can be similar to that as describe for the first heat exchanger 108 described in U.S. Patent No. 11 ,668,219. In said U.S. Patent No. 11 ,668,219 the first heat exchanger 108 is described as adapted and configured to remove heat from turbine exhaust gas passing through the turbine exhaust gas discharge structure 102 by transferring heat to a working fluid (e.g., carbon dioxide) passing through and within the first heat exchanger 108 to continuously (e.g., on demand) provide cooling to the turbine exhaust gas during operation. The aforesaid discussion of the present application of the catalytic exhaust gas treatment device 54 is similar to that describedfor the catalytic device 104 in U.S. Patent No. 11 ,668,219, and the discussion of the present application of the catalytic exhaust gas treatment device 56 is similar to that described for the catalytic device 106 in U.S. Patent No. 11 ,668,219. In the case of the present operation water could be preferable over carbon dioxide.

[0067] Downstream from the second cavity and within housing 23 is located a third cavity 60 which is sized to accommodate the installation of potential HRSG components for a Combined Cycle (CC) system operation,

[0068] With reference to Figures 1 and 2, the housing 23 further comprises a roof 64 comprising a generally flat detachable section 64A which overlies and covers cavity 35, a generally flat detachable section 64B which overlies and covers cavity 60, and section 64C which overlies cavity 44 and can be permanent or non-detachable unless there are potential plans to add or replace elements within cavity 44. The housing 23 further has a floor 68 as well as sidewalls 72, as known in the art, so that the flow path is enclosed by said floor 68, roof 64 and sidewalls 72. The roof sections 64A and 64B can be solid without any openings in them for exhaust flow to escape and to prevent rain or moisture from seeping through the roof 64. Roof section 64C likewise can be solid without any openings for exhaust to escape and to prevent rain or moisture from seeping through. Removable roof plugs can be installed in each of roof sections 64A and 64B as “welded” and can later be cut out, or the roof sections 64A and 64B can be bolted such as to a flange extending from the top or near the top of the sidewalls 72, roof beams, etc. so that they can later be unbolted for CC conversion and installation of HRSG components. When conversion to the CC configuration is desired after the simple cycle system 20 is constructed, the roof section 64A overlying cavity 35 and roof section 64B overlying cavity 60 can be removed so that HRSG components can be lowered into each of cavity 35 and 60 and installed. The final converted roof sections can arrive shop installed on the heating surface bundles to be dropped / set, for example, by a crane in with the bundle during installation and welded in place. As seen in Figs. 11 and 13, the final converted CC roof sections are shown as 64A’ and 64B’. Each roof section 64A’ and 64B’ comprises a plurality of segments 66 and 67 of generally rectangular or square shape, insulated for heat retention that form the complete roof sections 64A’ and 64B’ of the HRSG. Segments 66 and 67 are referred to in the art as “plugs”, or “module / bundle roof panels.” Each of the sections 66 and 67 is shown having openings illustrated as circular to receive the upper ends of various circular pipes 69. Each of the segments 66 and 67 have a pair of I-beams77 to provide the attached depending heat transfer surface bundle with mechanical / structural support.

[0069] Such HRSG components installed for CC conversion can be those such as previously discussed, and mentioned in U.S. Pat. No. 6,508,206, and in U.S. Pat. No. 10, 180,086, as well as in U.S. Patent No. 8,820,078 and U.S. Patent No. 9,435,228, U.S. Patent No. 9,909,462, and Patent No. 8,734,745. Generally, for CC conversion, the high pressure components and higher temperature components and intermediate range pressure and temperature components would be installed in the first cavity 35 beneath roof section 64A’, such as intermediate pressure reheater(s) and high pressure superheater(s), and high pressure evaporators.. A desuperheater would not be in the cavity 35 but outside of the roof section 64A’ when required for the specific design.

[0070] Typically, lower pressure and temperature components and intermediate components such as lower temperature heat exchanging coils, economizers, lower pressure superheaters, evaporators and steam drums, and feed water heaters, would be located within third cavity 60 beneath roof 64B’. Steam drums such as depicted as78 in Figs. 3 and 4 could be located above roof 64 such as above roof sections 64A’ and 64B’ as shown in Fig4, and in flow connection with such components as known in the art.

[0071] Such components would be interconnected and in flow connection among the respective components in a manner and fashion well known in the art, such as disclosed in the aforementioned referenced patents. During the aforesaid process, the roof section 64C would remain affixed to the exhaust gas structure and housing, unless there were some planned additions or replacement of components within cavity. The system following such installation is depicted in the elevation view of Fig.3 and the top plan view of Fig.4, as well as in Figs. 11 and 13. During the aforesaid conversion process the simple cycle procedure is inoperable and the unit would not be operable until the CC conversion to the Figs. 3 and 4 configuration is completed.

[0072] Now we turn to the second version of the disclosure which features the aforesaid bypass treatment that allows the simple cycle operation to continue during the conversion process. Figures 5 and 6 illustrate bypass housing ensemble 200 for exhaust gas structure such as previously described for Figures 1 - 4 of the first version that comprises an inlet section 205 of frustoconical shape having an opening 208 that receives TEG, as well as sidewalls, floor and a roof structure as described for Figures1 - 4. The distal part of inlet section 205 is in flow connection with a second section 210 which acts as an initial bypass section 210, which has a floor, roof and sidewalls. A third section 215 acts as a second bypass section, which also has a floor, roof and sidewalls. Initial bypass section 210 has sidewalls each having a corresponding opening 217, and section 215 sidewalls each having a corresponding opening 219. A pair of bypass conduits 222 and 224, are shown as a pair of generally “C” shaped but there are many other configurations including various quantities of bypass ducts intended to be included herein. Each conduit 222 and 224 has an inlet end secured as by flange and bolt and / or welded connections to be in flow connection with the section 210 side wall openings 217 and an outlet end in flow connection with the sidewall openings 219 in section 215 as by flange and bolt and / or welded connections. In between the two sections 210 and 215 lies a first area of space 225 reserved for construction of future HRSG components. The sections 210 and 215 each have plates 228 and 230 which can be of steel, respectively, that are secured such as by flange and bolt and / or welded connections to respective sections 210 and 215, to seal off the sections 210 and 215 from one another. Plates 228 and 230 can be removed in the future by removing their fastening bolts and / or welded connections should HRSG components be installed in the area of space 225 to allow flow from section 210 to pass into section 215. The bypass conduits 222 and 224 each extend to the outside of space 225 to thus bypass space 225 leaving room for installing HRSG components in the future. Thus, exhaust gas can flow through bypass conduits 222 and 224 from section 210 into section 215 and thence into section 240. Sections 210 and 215 are hence designed to serve as parts of an overall HRSG housing, such as in Fig. 8. As an example of another style of bypass ducting , with further reference to the previously discussed Figure 12 the bypass “C” shaped conduits of Figures 5-8 could be configured as a plurality of round conduits also potentially including bypass dampers and internal distribution manifolds as discussed in 0022 above. Many others are possible bypass configurations available and known in the art and are intended to be incorporated herein.

[0073] Section 215 has a downstream opening in flow connection with the proximal end of an intermediate housing section 240. Section 240 has a floor, roof and sidewalls. Thus, exhaust gas can flow through bypass conduits 222 and 224 from section 210 into section 215 and thence into section 240. Section 240 houses one or more catalytic converter components such as previously discussed with regard to theversion of Figures 1 - 4. Section 240 also has a heat exchanging coil 238 positioned upstream of the said one or more catalytic converters. Coil 238 functions in a like manner as described for coil 38 in the embodiment of Figures 1 -4. As for the aforementioned U.S. Patent No. 11 ,668,219, the operation of coil 238 can be similar to that as describe for the first heat exchanger 108 described in U.S. Patent No. 11 ,668,219. In said U.S. Patent No. 11 ,668,219 the first heat exchanger 108 is described as adapted and configured to remove heat from turbine exhaust gas passing through the turbine exhaust gas discharge structure 102 by transferring heat to a working fluid (e.g., carbon dioxide) passing through and within the first heat exchanger 108 to continuously (e.g., on demand) provide cooling to the turbine exhaust gas during operation. The aforesaid discussion of the present application of the catalytic exhaust gas treatment devices for the Fig. 5-7 embodiment is similar to that described for the catalytic devices 104 and 106 in U.S. Patent No. 11 ,668,219.

[0074] Section 240 has a zone 250 towards its distal end. Downstream of section 240 and zone 250 is a section 260 which comprises an exhaust stack 262 and surrounding structure.

[0075] The section 240 sidewalls have a pair of openings 242 adjacent zone 250 and section 260 has sidewalls having a second pair of openings 267. A pair of bypass conduits 265 and 268, are shown as generally “C” shaped but there are many other configurations intended to be included herein, Each bypass conduit 265 and 268 has an inlet end fastened as by bolts and / or can be welded to the sidewalls of section 240 to be in flow connection with the section 240 side wall openings 242. Each conduit 265 and 268 has an outlet end fastened to the section 260 sidewalls as by a bolts and flanges and / or welded arrangement to be in flow connection through the sidewall openings 267 in section 260. In between the two sections 240 and 260 lies a second area of space 275 reserved for construction of future HRSG components. The bypass conduits 265 and 268 each extend to the outside of space 275 to thus bypass space 275. The sections 240 and 260 each have blocking plates 270 and 274, respectively, which can be of steel and can be fastened as by bolts and / or can be welded, to seal off the section 275. Thus, a flow path exists from zone 250 of section 240 to flow through the bypass conduits 265 and 268 into section 260 and through stack 262. In the future, should HRSG components be installed in the area of space 275, the securing bolts can be unfastened and / or welded attachments cut and the plates 270 and 274 removed. The bypass conduits 265 and 268 can be unfastened from thesections 240 and 260, respectively, and the openings 242 and 260 can be blocked. Turbine exhaust flow can then be in flow connection through the flow path through 275 to allow exhaust gas flow from section 240 into section 260 and through stack 262 as parts of an overall HRSG housing, such as shown in Fig. 8.

[0076] As seen in the Fig. 7 embodiment, the system can function with a single bypass conduit in both bypass conduit arrangements. In Fig. 7 a single conduit 268’ is shown connecting the sections 240 and 260. Likewise, a single conduit 222” or 224’ could be used to connect sections 210 and 240.

[0077] FIG. 9 is a representation of a potential arrangement of external equipment that can be later added to a SC unit of this disclosure. FIG. 9 represents an arrangement of external equipment that is similar to that represented in FIG. 10 of this application, which is a copy of FIG. 1 from U.S. Patent Nos. 11 ,668,219, which is incorporated herein by reference as if fully set forth herein. In a manner similar to that represented in FIG. 10, the SC unit could involve the addition of a cooling loop that includes a heat exchanger such as the heat exchanger 108 represented in FIG. 10 into the housing of a SC unit with the remaining components of the cooling loop being external to the housing.

[0078] The equipment represented in FIG. 9 includes a schematic representation of a cooling coil of a heat exchanger 408 within the SC unit according to the method of this application. The heat exchanger 408 is positioned in the housing of the SC unit in front of an exhaust gas treatment device of the type described earlier. The heat exchanger 408 is connected in a cooling loop that is external to the housing.

[0079] The heat exchanger 408 communicates cooling fluid to a second, external heat exchanger 404 in the form of an air-cooled heat exchanger. The air-cooled heat exchanger 404 is adapted and configured to remove heat from the working fluid gained at the first heat exchanger 408. The air-cooled heat exchanger 404 can include a fan 406 that passes air over the second heat exchanger 404 to transfer heat to the atmosphere. Thus, the second heat exchanger 404 could alternatively include a water- cooled cooling tower.

[0080] The working fluid leaving the second heat exchanger 404 passes through a circulating pump 409. The pump 409 drives the working fluid through the cooling loop back to the first heat exchanger 408. The controls for the system provide that the temperature of the flue gas exiting heat exchanger 408 is in the correct temperature range for the catalyst devices such as 56, 59 and 59 herein.[0081 JThe external equipment represented in FIG. 9 also includes a mass inventory management system in the form of a working fluid storage tank 412. The storage tank 412 is in fluid communication with a pump 414 that is adapted and configured to add or remove working fluid from the cooling loop.

[0082] A pressure control tank 416 is also connected in fluid communication with the cooling loop. A nitrogen system or any other feature capable of pressure control can be used to pressure control tank 416. In the figure, the pressure control tank 416 is in fluid communication with a pressure safety valve 418 and a nitrogen pressurization system and together the pressure controlled tank 416, the nitrogen system, and the pressure safety valve 418 control the system internal pressure and prevent the pressure of the working fluid flowing through the cooling loop from exceeding a maximum pressure.

[0083] With reference for example to Figure 6, when it is desired to convert to a CC system, the HRSG components with preinstalled roofs are lowered by crane, for example, such as described for the Figures 1 - 4 version, into the first area of space 225 and into the second area of space 275. The preinstalled roof sections can generally have the same configuration as previously described for roof sections 64A’ and 64B’ and their roof segments (plugs) 66 and 67, associated I-beams 77, with pipes 69 extending upwardly therefrom, such as shown and described as to Figures 8, 1 1 and 13. The installed HRSG high pressure components and higher temperature components and intermediate range pressure and temperature components such as intermediate pressure reheater(s) and high pressure superheater(s), and high pressure evaporators., would be installed in the first open space 225 beneath roof section 64A’. Typically, lower pressure and temperature components and intermediate components such as lower temperature heat exchanging coils, economizers, lower pressure superheaters, evaporators, and feed water heaters, could be installed in the second open space 275 beneath roof section 64B’. Steam drums such as depicted as 78 could be located above roof sections 64A and 64B’ as shown in Fig. 8, and connected with such components as known in the art, A desuperheater would also be outside of the roof section 64A’ and 64B’ when required for the specific design.

[0084] 0nce the proper HRSG components are correctly connected, the sections 210 and 215 each have their blocking plates 228 and 230, respectively, removed therefrom. Likewise, plates 270 and 274 are removed from sections 240 and 260, respectively. The plate removals open up a flow path through section 240 for theHRSG components. The bypass conduits 222, 224, 265 and 268 can be removed. The sidewall section 210 openings 217, and sidewall section 215 openings 219, are closed by sidewall structure so that the section 215 and sidewalls are sealed closed to prevent leakage. Likewise, sidewall section 240 openings 242, and sidewall section 260 openings 267, are closed by sidewall structure.

[0085] The foregoing improvements in the art illustrated and discussed with regard to Figures 1 -13 can be implemented in association with the two module wide system 100, the three module wide system 110 , and the four module wide “shop modular” style system 120, shown respectively in the previously discussed Figures 14-16.

[0086] It should also be understood that the turbine exhaust gas can be cooled for a purpose other than improving the treatment of the turbine exhaust gas (e.g., for the reduction in carbon monoxide and / or nitrogen oxides). For example, the turbine exhaust gas can be cooled to maintain the turbine exhaust gas within a specific temperature range irrespective of a temperature range for treating the turbine exhaust gas. This can allow for processing of the turbine exhaust gas into other products or other uses of the turbine exhaust gas such as controlling heat input into the combined cycle.

[0087] It should also be understood that the systems described transfer heat from the turbine exhaust gas to a plurality of locations / applications where said energy can be used for other heating applications and / or power generation. The heated working fluid can heat other process fluids through a heat exchanger. The heated working fluid can drive a mechanical device (e.g., a pump). Further, the heated working fluid can be expanded to drive a turbine which in turn drives an electrical generator.

[0088] As various changes could be made in the above constructions and methods without departing from the broad scope of the disclosure, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

Claims

AMENDED CLAIMS received by the International Bureau on 21 OCT 2025 (21.10.2025)What is claimed is:1 . A method for construction of providing a simple cycle system using a gas turbine driven generator with emissions control components with the capability of further constructing a combined cycle system that includes heat recovery steam generator components in conjunction with the emission control components of the simple cycle system, comprising at least the following steps: a. providing an exhaust gas discharge structure adapted and configured to receive exhaust gas from a combustion source, the exhaust gas discharge structure having an inlet for receiving exhaust gas; b. providing a first area of space for construction of heat recovery steam generator components; c. providing a first bypass conduit configured for flow of said exhaust gas, said first bypass conduit configured to extend in a direction to allow for construction of heat recovery steam generator components in the first area of space, the first bypass conduit having an inlet opening configured to receive flow of exhaust gas from the gas powered turbine; d. providing at least one catalytic exhaust gas treatment device within the exhaust gas discharge structure adapted and configured to receive turbine exhaust gas from the first bypass conduit and treat at least one component of the turbine exhaust gas through a catalytic reaction between a catalyst contained within the catalytic exhaust gas treatment device and the at least one component of the exhaust gas; e. providing a second area of space for construction of a second group of heat recovery steam generator components; and f. providing a second bypass conduit configured for flow of said exhaust gas, said second bypass conduit configured to extend in a direction to allow for construction of heat recovery steam generator components in the second area of space, the second bypass conduit having an inlet opening configured to receive flow of exhaust gas that has flowed through the said at least onecatalytic exhaust gas treatment device and which has an exit flow connection to the exhaust system downstream of said second area of space.

2. The method of claim 1 , further comprising providing a first blocking component located and configured in association with the exhaust gas discharge structure to direct flow of exhaust gas into the inlet of the first bypass conduit.

3. The method of claim 2, further comprising providing a second blocking component located and configured in association with the exhaust gas discharge structure at a position downstream from the said first area of space, further providing the said first bypass conduit configured with an outlet and providing the exhaust gas discharge structure having an inlet that is in flow connection with the outlet of the said first bypass conduit at a location to allow flow of exhaust gas through the first bypass conduit into the exhaust gas discharge structure at a position downstream of the second blocking structure.

4. A method for construction of providing a simple cycle system using a gas turbine driven generator with emissions control components with the capability of further constructing a combined cycle system that includes heat recovery steam generator components in conjunction with the emission control components of the simple cycle system, comprising at least the following steps: a. providing an exhaust gas discharge structure adapted and configured to receive exhaust gas from a combustion source, the exhaust gas discharge structure having an inlet for receiving exhaust gas; b. providing a first area of space for construction of heat recovery steam generator components; c. providing a first bypass conduit configured for flow of said exhaust gas, said first bypass conduit configured to extend in a direction to allow for construction of heat recovery steam generator components in the first area of space, the first bypass conduit having an opening configured to receive flow of exhaust gas from the gas powered turbine; d. providing at least one catalytic exhaust gas treatment device within the exhaust gas discharge structure adapted and configured to receive turbineexhaust gas from the first bypass conduit and treat at least one component of the turbine exhaust gas through a catalytic reaction between a catalyst contained within the catalytic exhaust gas treatment device and the at least one component of the exhaust gas; e. providing a second area of space for construction of a second group of heat recovery steam generator components; and f. providing a second bypass conduit configured for flow of said exhaust gas, said second bypass conduit configured to extend in a direction to allow for construction of heat recovery steam generator components in the second area of space, the second bypass conduit having an inlet opening configured to receive flow of exhaust gas that has flowed through the said at least one catalytic exhaust gas treatment device and which has an exit flow connection to the exhaust system downstream of said second area of space.

5. A method for construction of providing a simple cycle system using a gas turbine driven generator with emissions control components with the capability of further constructing a combined cycle system that includes heat recovery steam generator components in conjunction with the emission control components of the simple cycle system, comprising at least the following steps: a. providing an exhaust gas discharge structure adapted and configured to receive exhaust gas from a combustion source, the exhaust gas discharge structure comprising a housing having a roof and an inlet for receiving exhaust gas; b. the housing having a first cavity for installation of heat recovery steam generator components, the roof having a first section overlying the first cavity; c. the housing having a second cavity for installation of heat recovery steam generator components, the roof having a second section overlying the second cavity;d. the housing having a third cavity, the third cavity being located between the first and second cavities, the roof having a third section overlying the third cavity; e. providing at least one catalytic exhaust gas treatment device within the third cavity adapted and configured to receive turbine exhaust gas from the housing inlet and to treat at least one component of the turbine exhaust gas through a catalytic reaction between a catalyst contained within the catalytic exhaust gas treatment device and the at least one component of the exhaust gas; f. providing the housing with a discharge outlet for turbine exhaust gas with a flow path from the inlet to the outlet for passage of exhaust gas through the housing; g. installing the exhaust gas structure to function as a simple cycle outlet to receive turbine exhaust gas; h. after the installing of the exhaust gas structure to function as a simple cycle outlet, the step of removing the first roof section to allow installing of heat recovery generator components followed by the step of installing heat recovery generator components in the first cavity; and i. after the installing of the exhaust gas structure to function as a simple cycle outlet, the step of removing the second roof section to allow installing of heat recovery generator components followed by the step of installing heat recovery generator components in the second cavity.

6. The method of claim 3, further comprising providing a third blocking component located and configured in association with the exhaust gas discharge structure to direct flow of exhaust gas into the inlet of the second conduit.

7. The method of claim 6, further comprising providing a fourth blocking component located and configured in association with the exhaust gas discharge structure at a position downstream from the said second area of space, further providing the said second conduit configured with an outletand providing the exhaust gas discharge structure having an inlet that is in flow connection with the outlet of the said second conduit at a location to allow flow of exhaust gas through the second conduit into the exhaust gas discharge structure at a position downstream of the fourth blocking structure.

8. The method of Claim 3 further comprising providing the exhaust gas structure with wall structure having a first opening and a second opening, the wall structure first opening being in flow connection with the inlet opening of the first conduit and the wall structure second opening being in flow connection with the outlet of the first conduit.

9. The method of Claim 8 further comprising providing the exhaust gas structure with wall structure having a third opening and a fourth opening, the wall structure third opening being in flow connection with the inlet opening of the second conduit and the wall structure fourth opening being in flow connection with the outlet of the second conduit.

10. The method of Claim 9 wherein the exhaust gas structure has an exhaust stack in flow connection with the atmosphere for receiving exhaust gas flow, after the provision of the first and second conduits, first heat recovery steam generator components are installed in the first area of space, and second heat recovery steam generator components are installed in the second area of space, the steps of removing the first and second conduits from the wall structure, closing the openings in the wall structure, removing the first, second, third and fourth blocking components from the exhaust gas discharge structure; to provide a flow path from the inlet of the exhaust gas discharge structure through the installed heat recovery steam generator components and through the exhaust stack.

11. The method of claim 5, wherein the first roof section is fastened in relationship to the housing by removable bolts, and in the step of removing the first roof section the bolts are removed by separation from being fastened in relationship to the housing to disengage the first roof section from the housing.

12. The method of claim 5, wherein the second roof section is fastened in relationship to the housing by removable bolts, and in the step of removing the second roof section the bolts are removed from being fastened in relationship to the housing to disengage the second roof section from the housing.

13. The method of claim 5, wherein the first roof section is comprised of a plurality of roof plugs fastened in relationship to the housing, and in the step of removing the first roof section the roof plugs are removed by separation from being fastened in relationship to the housing to disengage the first roof section from the housing.

14. The method of claim 5, wherein the second roof section is comprised of a plurality of roof plugs fastened in relationship to the housing, and in the step of removing the second roof section the roof plugs are removed by separation from being fastened in relationship to the housing to disengage the second roof section from the housing.

15. The method of claim 5, wherein the first cavity of the housing has a coil of tubes positioned within the housing and configured to operate from a flow of fluid that is separate from a flow of fluid flowing to any future heat recofvery steam generator components to thus be operable during simple cycle operation to heat fluid flowing therethrough.

16. The method of claim 15, wherein the coil of tubes positioned within the housing is in fluid flow connection with a pipe that extends outside of the housing.

Images