Patent Application
20160076457
A turbomachine such as a gas turbine typically includes a compressor, combustor, and turbine. The compressor increases the pressure of gases, typically air, and the compressed gas is mixed with gas fuel by the combustor and burned, resulting in hot gases. The heated gases are used to drive a turbine which generates power.
Gas turbine components are cleaned to maintain performance and to extend the overall lifetime of the component, e.g., by reducing the degradation of gas turbine components due to foulants. Cleaning may remove foulants, such as smoke, water vapor, soot, grease, oil film, and organic vapors. Gas turbine components may be cleaned while the gas turbine is not in operation. This cleaning, referred to as offline cleaning, may be performed manually. An example of manual cleaning is crank washing. Crank washing is generally performed by the introduction of a cleaning solution into a turbine while slow cranking takes place. This cranking occurs without ignition or fuel being introduced. Since the gas turbine is not in operation while crank washing is performed, the productivity of the gas turbine is reduced. Cleaning of gas turbine components while the gas turbine is online can be done as well. Such methods often involve the use of additional equipment and/or manual cleaning.
These cleaning methods are employed to remove foulants which have accumulated on gas turbine components. However, after cleaning, gas turbine components are again susceptible to damage during service due to the presence and accumulation of foulants.
Therefore, a need exists for a system and method for treating a turbomachine surface, such as the surface of a gas turbine, which imparts protection from foulants and damage related thereto, is performed manually or automatically while the gas turbine is online or offline, and/or which employs existing equipment of the gas turbine, thereby extending the period of time between repairs and/or maintenance intervals, extending the lifetime of the component and/or improving the productivity of the gas turbine.
According to one aspect of the invention, a method comprises mixing a filming agent with a liquid to form a filming solution, wherein the filming agent comprises siloxane, fluorosilane, mercapto silane, amino silane, tetraethyl orthosilicate, succinic anhydride silane, or a combination comprising at least one of the foregoing.
According to another aspect of the invention, a system comprises a processor and a system memory communicatively coupled to the processor a system memory communicatively coupled to the processor, the system memory having stored thereon executable instructions that when executed by the processor cause the processor to effectuate operations comprising receiving data from a sensor; and providing instructions to initiate an online wash and to dispense a filming agent onto a surface using a wash nozzle based on the data received from the sensor, wherein the filming agent comprises siloxane, fluorosilane, mercapto silane, amino silane, tetraethyl orthosilicate, succinic anhydride silane, or a combination comprising at least one of the foregoing.
According to another aspect of the invention, a filming control system comprises a storage tank configured to contain a filming agent, a plurality of nozzles, and a supply conduit coupled to the storage tank on a first end and the plurality of nozzles on a second end; wherein the filming control system is configured to deliver the filming agent from the storage tank and to discharge the filming agent through the plurality of nozzles and the filming agent comprises siloxane, fluorosilane, mercapto silane, amino silane, tetraethyl orthosilicate, succinic anhydride silane, or a combination comprising at least one of the foregoing.
These and other advantages and features will become more apparent from the following description taken in conjunction with the drawings.
The subject matter, which is regarded as the invention, is particularly pointed out and distinctly claimed in the claims at the conclusion of the specification. The foregoing and other features, and advantages of the invention are apparent from the following detailed description taken in conjunction with the accompanying drawings in which:
The detailed description explains embodiments of the invention, together with advantages and features, by way of example with reference to the drawings.
Disclosed herein are methods and systems for the application of a film treatment to impart fouling resistance to a surface, such as a surface of a turbomachine, compressor or gas turbine. In an embodiment and as described in further detail below, the film treatment comprises one or more filming agents. The filming agent comprises siloxane, fluorosilane, mercapto silane, amino silane, tetraethyl orthosilicate, succinic anhydride silane, or a combination comprising at least one of the foregoing.
The gas turbine 10 further comprises an air extraction system 122. The air extraction system 122 extracts a portion of the flow of air 120 in the compressor 24 for use in cooling the turbine and for other purposes. The air extraction system 122 includes one or more air extraction pipes 124. The air extraction pipes 124 extend from an extraction port 126 about one of the compressor stages towards one of the stages of the turbine. In this example, an X-stage extraction pipe 128 and a Y-stage extraction pipe 130 are shown. The X-stage extraction pipe 128 is positioned about an nth stage and the Y-stage extraction pipe 130 is positioned about an mth stage. Extractions from other stages of the compressor 24 also may be used. The X-stage extraction pipe 128 is in communication with an X-stage turbine pipe 132 while the Y-stage extraction pipe 130 is in communication with a Y-stage turbine pipe 134. The X-stage turbine pipe 128 corresponds with a particular stage of the turbine and the Y-stage turbine pipe 130 corresponds with a different stage of the turbine, for example. In another embodiment, the air extraction system 122 has quick-disconnect provisions. The quick-disconnect provisions are located on the air extraction pipes 124, and are part of any or all of the individual extraction pipes, such as the Y-stage extraction pipe 130, for example. In an aspect of the embodiment, the quick-disconnect provisions directly connect to an extraction port 126.
The gas turbine film treatment system 200 includes a storage tank 214 that contains a filming agent. Multiple storage tanks for multiple types of filming agents or for a single type of filming agent may be used. In one embodiment, the filming agent comprises a silane. In another embodiment, the filming agent is a mixture of a first silane and a second silane, e.g., fluorosilane and mercapto silane. The first silane and the second silane are mixed at a predetermined ratio. In one aspect of the embodiment, the filming agent is a 1:1 mixture of fluorosilane and amino silane. The mixing may be done in advance or on-demand. In another embodiment, the filming agent is combined with an aqueous liquid such as deionized water. “Deionized water” is interchangeable with “demineralized water”. The filming agent is mixed with the deionized water at a predetermined ratio. In an embodiment, the pH of the filming agent, the deionized water, or the mixture of the two may be adjusted. For example, this pH adjustment may be performed using acetic acid. In another embodiment, a non-ionic surfactant is added to the filming agent in order to improve water solubility. In yet another embodiment, the pH of the filming agent, the deionized water or a mixture comprising the two is adjusted to a pH from about 5 to about 9, specifically from about 5.5 to about 8.5, more specifically from about 6.5 to about 7.5.
The storage tank 214 is optionally provided with a level sensor 216 and is coupled through a conduit 215 to a supply pump 218. The supply pump 218 is connected to an online wash system 210 through a filming agent flow modulating valve 222 disposed in filming agent conduit 220. The online wash system 210 includes a plurality of nozzles 212 that direct the filming agent to the compressor 202. A pressure sensor 223 and a flow sensor 224 are disposed in the filming agent conduit 220 to provide data to control the flow of the filming agent to the online wash system 210. The gas turbine film treatment system 200 also optionally includes a source of deionized water 230 or other aqueous or non-aqueous liquid (or solvent) coupled to a water conduit 231 which is coupled to a filming agent conduit 220 through a water flow modulating valve 226. A flow sensor 224 is disposed in the water conduit 231. In an embodiment, the gas turbine filming treatment system 200 further comprises quick disconnect provisions in place of or in addition to the storage tank 214 and/or the deionized water source 230. The quick-disconnect provisions are incorporated into the filming agent flow modulating valve 222 and/or the water flow modulating valve 226. The quick-disconnect provision is used for external supply, such as from a supply truck.
The gas turbine film treatment system 200 may also include a controller 232. The controller 232 receives inputs 234 such as the level of fouling of the compressor 202, the level of the storage tank 214, the flow rate of the supply pump 218, the status of the supply pump 218, the flow rate of the filming agent to the compressor 202, the flow rate of deionized water from the deionized water source 230, the status of the deionized water flow modulating valve 226, the status of the filming agent flow modulating valve 222, the operating status of the gas turbine 201, the status of the plurality of nozzles 212, and/or any other inputs relative to the status or operation of the gas turbine film treatment system 200. In one aspect of the embodiment, the controller 232 determines the ratio of the filming agent to deionized water in the filming solution produced therefrom. For example, the controller 232 determines the amount of the filming agent to include or not include in the filming solution. In another aspect of the embodiment, the controller 232 determines the ratio of substances to mix to prepare the filming agent. The filming agent is mixed automatically at a predetermined ratio, adjustable based on the type of filming agent, and injected into the bellmouth 118. The online wash system 210 may be used for the injection. The nozzles 212 of the online wash system 210 may be used to dispense the filming agent or the filming solution. In one embodiment, the online wash system 210 is used for rinsing the gas turbine 201 with a liquid. In one embodiment, that liquid may be deionized water. Inlet and drain values may be optimally positioned and aligned prior to introduction of the filming agent or filming solution. The mixing to produce the filming agent or filming solution may be done in advance or at the time a demand is made. In one embodiment, the controller 232 mixes fluorosilane and mercapto silane in equal parts to produce the filming agent. In an aspect of the embodiment, the controller 232 then mixes a metered amount of the filming agent with a metered amount of deionized water to produce the filming solution. In another embodiment, fluorosilane and mercapto silane may already be mixed to produce the filming agent and stored in the storage tank 214. Water and the filming agent may then be mixed in a predetermined ratio to produce the filming solution. The ratio may be adjusted based on the particular filming agent employed.
The controller 232 provides outputs 236 such as instructions or control signals to the filming agent flow modulating valve 222, water flow modulating valve 226, supply pump 218, and/or to any other component or system. The controller 232 is self-contained or, alternatively, is integrated into a larger control system. The controller 232 monitors various sensors and other instruments associated with a turbine system, such as gas turbine 201. In addition to controlling certain turbine functions, such as fuel flow rate, the controller 232 optionally generates data from its turbine sensors and presents that data for display to the turbine operator. The data may be displayed using software that generates data charts and other data presentations.
An example of the controller 232 is a computer system that includes microprocessors that execute programs to control the operation of the turbine system using sensor inputs, such as inputs 234, and instructions from human operators. The computer system includes logic units, such as sample and hold, summation and difference units that may be implemented in software or by hardwire logic circuits. The commands generated by the computer system processors cause actuators on the turbine system to, for example, adjust the fuel control system that supplies fuel to the combustion chamber, set the inlet guide vanes to the compressor 202, and adjust other control settings on the turbine system. The description of computer system features and functionality is exemplary only and is non-limiting as to the disclosure.
The filming agent comprises a silane, such as siloxane, fluorosilane, mercapto silane, tetraethyl orthosilicate, amino silane, or a combination comprising at least one of the foregoing. Silanes, such as fluorosilane and siloxane, for example, are monomeric silicon chemicals. Silanes impart qualities such as hydrophobicity, abrasion resistance, temperature resistance, oleophobicity, and passivity, among others. It should be understood that the term “silane” is used to encompass the group of chemicals and not just a particular silane.
In an exemplary embodiment, system 200 is configured for film treating the gas turbine when the gas turbine is offline or online. A gas turbine is considered offline when the machine, such as a compressor or turbine section, is operating at significantly below normal operating temperature. For example, for an offline film treatment, the gas turbine may be cooled down until the interior volume and surfaces have cooled down sufficiently, for example, to around 145° F., so that water or a filming or cleaning solution being introduced into the gas turbine will not thermally shock the internal metal and induce creep, or induce any mechanical or structural deformation of the material.
Illustrated in
At 402, a filming agent is selected. The selection may be automatic or based on an operator selection.
At 404, the filming agent is applied to a gas turbine 201 surface, such as a blade (e.g., 106, 108, 110), vane 114, rotor wheel 112, or casing 116, using a gas turbine wash nozzle 212.
Illustrated in
At 502, a fouling threshold level is established. The threshold level is an overall fouling level or a specific level of one or more foulants. The fouling level is measured at one or more locations in the gas turbine 201, and one or more locations are used to establish the threshold level.
At 504, the fouling level of the compressor 202 is sensed.
At 506, the fouling level is communicated to the controller 232. The controller 232 may show this information on a display or send it to an operator.
At 508, it is determined whether the fouling threshold has been met.
At 510, a filming agent, such as a mixture of fluorosilane and mercapto silane, is mixed with water, such as deionized water.
At 512, the filming solution is dispensed into the compressor 202. The gas turbine film treatment system 200 may be used to apply the filming solution using the online wash system 210 while the gas turbine 201 is online.
At 514, the compressor is rinsed with water, such as deionized water. The gas turbine film treatment system 200 is used to rinse the compressor 202 using the online wash system 210 while the gas turbine is online.
The computer 720 may further include a hard disk drive 727 for reading from and writing to a hard disk (not shown), a magnetic disk drive 728 for reading from or writing to a removable magnetic disk 729, and an optical disk drive 730 for reading from or writing to a removable optical disk 731 such as a CD-ROM or other optical media. The hard disk drive 727, magnetic disk drive 728, and optical disk drive 730 are connected to the system bus 723 by a hard disk drive interface 732, a magnetic disk drive interface 733, and an optical drive interface 734, respectively. The drives and their associated computer-readable media provide non-volatile storage of computer readable instructions, data structures, program modules and other data for the computer 720. As described herein, computer-readable media is a tangible, physical, and concrete article of manufacture and thus not a signal per se.
Although the exemplary environment described herein employs a hard disk, a removable magnetic disk 729, and a removable optical disk 731, it should be appreciated that other types of computer readable media which can store data that is accessible by a computer may also be used in the exemplary operating environment. Such other types of media include, but are not limited to, a magnetic cassette, a flash memory card, a digital video or versatile disk, a Bernoulli cartridge, a random access memory (RAM), a read-only memory (ROM), and the like.
A number of program modules may be stored on the hard disk, magnetic disk 729, optical disk 731, ROM 724 or RAM 725, including an operating system 735, one or more application programs 736, other program modules 737 and program data 738. A user may enter commands and information into the computer 720 through input devices such as a keyboard 740 and pointing device 742. Other input devices (not shown) may include a microphone, joystick, game pad, satellite disk, scanner, or the like. These and other input devices are often connected to the processing unit 721 through a serial port interface 746 that is coupled to the system bus 723, but may be connected by other interfaces, such as a parallel port, game port, or universal serial bus (USB). A monitor 747 or other type of display device is also connected to the system bus 723 via an interface, such as a video adapter 748. In addition to the monitor 747, a computer may include other peripheral output devices (not shown), such as speakers and printers. The exemplary system of
The computer 720 may operate in a networked environment using logical connections to one or more remote computers, such as a remote computer 749. The remote computer 749 may be a personal computer, a server, a router, a network PC, a peer device or other common network node, and may include many or all of the elements described above relative to the computer 720, although only a memory storage device 750 has been illustrated in
When used in a LAN networking environment, the computer 720 is connected to the LAN 751 through a network interface or adapter 753. When used in a WAN networking environment, the computer 720 may include a modem 754 or other means for establishing communications over the wide area network 752, such as the Internet. The modem 754, which may be internal or external, is connected to the system bus 723 via the serial port interface 746. In a networked environment, program modules depicted relative to the computer 720, or portions thereof, may be stored in the remote memory storage device 750. It will be appreciated that the network connections shown are exemplary and other means of establishing a communications link between the computers may be used.
Computer 720 may include a variety of computer readable storage media. Computer readable storage media can be any available media that can be accessed by computer 720 and includes both volatile and nonvolatile media, removable and non-removable media. By way of example, and not limitation, computer readable media may comprise computer storage media and communication media. Computer storage media include both volatile and nonvolatile media, removable and non-removable media implemented in any method or technology for storage of information such as computer readable instructions, data structures, program modules or other data. Computer storage media include, but are not limited to, RAM, ROM, EEPROM, flash memory or other memory technology, CD-ROM, digital versatile disks (DVD) or other optical disk storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other medium which can be used to store the desired information and which can be accessed by computer 720. Combinations of any of the above should also be included within the scope of computer readable media that may be used to store source code for implementing the methods and systems described herein. Any combination of the features or elements disclosed herein may be used in one or more embodiments.
A technical effect of the embodiments described herein is to provide a system and method for providing a film treatment to a surface, such as the surface of a turbomachine or more specifically a gas turbine, which imparts protection from foulants and damage related thereto, is performed manually or automatically while the gas turbine is online or offline, and/or which employs existing equipment of the gas turbine, thereby extending the period of time between repairs and/or maintenance intervals, extending the lifetime of the component and/or improving the productivity of the gas turbine.
The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. Where the definition of terms departs from the commonly used meaning of the term, applicant intends to utilize the definitions provided herein, unless specifically indicated. The singular forms “a,” “an,” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be understood that, although the terms first, second, etc. may be used to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. The term “and/or” includes any, and all, combinations of one or more of the associated listed items. The phrases “coupled to” and “coupled with” contemplates direct or indirect coupling.
Each of Samples 1-4 was prepared according to the ratios set forth in Table 1 to produce a filming agent. Each of the filming agents of Samples 1-4 was prepared by mixing the identified first silane and second silane in a 1:1 ratio. In addition, each of the Samples 1-4 was prepared according to an aqueous formulation or an organic solvent formulation. For the aqueous formulations, the pH of the distilled water was adjusted to 4.5-5.5 using acetic acid and then the silane mixture was added in with continuous stirring. A suitable amount of non-ionic surfactant was added in some samples as needed to enhance the solubility of the silane mixture in the distilled water. For the organic solvent formulations, the pH of a mixture of 95% ethanol and 5% distilled water was adjusted to 4.5-5.5 using an acetic acid and then the silane mixture was added in with continuous stirring.
Film treatments were applied to gas turbine components using the filming agents of Samples 1-4, respectively. The film-treated gas turbine components were preheated to 200° C. and soaked in a foulant blend for 30 minutes. After being dried overnight at 150° C., there was little or no foulant present on the gas turbine components.
Sample 5 is an aqueous filming solution prepared by mixing a silane with deionized water at a concentration of 0.5-2.0% with continuous stirring. The pH was adjusted to 4.5-5.5 using acetic acid. In Sample 6, 0.1% of a non-ionic surfactant was added to improve the solubility of the silane in the deionized water.
Film treatments were applied to gas turbine components using the filming solutions of Samples 5-6, respectively. The film-treated gas turbine components were preheated to 200° C. and soaked in a foulant blend for 30 minutes. After being dried overnight at 150° C., there was little or no foulant present on the gas turbine components.
The results of Examples 1-4 thus demonstrate that the gas turbine film treatment methods and systems described herein result in significantly reduced fouling of gas turbine components.
While the invention has been described in detail in connection with only a limited number of embodiments, it should be readily understood that the invention is not limited to such disclosed embodiments. Rather, the invention can be modified to incorporate any number of variations, alterations, substitutions or equivalent arrangements not heretofore described, but which are commensurate with the spirit and scope of the invention. Additionally, while various embodiments of the invention have been described, it is to be understood that aspects of the invention may include only some of the described embodiments. Accordingly, the invention is not to be seen as limited by the foregoing description, but is only limited by the scope of the appended claims.
