US20140080403A1

US20140080403A1 - Methods and system design for providing leak detection of volatile liquid hydrocarbon vapors

Info

Publication number: US20140080403A1
Application number: US13/618,440
Authority: US
Inventors: Dean Matthew Erickson; Gary Cletus Mobley, JR.; Len Alan Wolf
Original assignee: General Electric Co
Current assignee: General Electric Co; Baker Hughes Holdings LLC
Priority date: 2012-09-14
Filing date: 2012-09-14
Publication date: 2014-03-20

Abstract

Embodiments are directed to a ventilation unit configured to exhaust drawn-in air from an enclosure, and a detection unit integrated with the ventilation unit and configured to detect a vapor. Embodiments are directed to a collection mechanism configured to collect liquid, a detection unit configured to sample vapor emitted from the liquid of the collection mechanism, and a ventilation unit integrated with the detection unit and configured to exhaust the vapor subsequent to the vapor having been sampled by the detection unit.

Description

BACKGROUND OF THE DISCLOSURE

The subject matter disclosed herein relates to leak detection. For example, aspects of the disclosure are directed to detecting a leak based on an emission of vapors.
Increasingly, fuels that have a low ignition temperature are being used in connection with one or more applications, such as a gas turbine. If a leak in a gas turbine develops, evaporation of the liquid fuel may pose a risk of ignition, particularly if the associated vapors are allowed to aggregate or form pockets.
Extraction pipes have been used as a part of a detection mechanism to detect leaking liquid. The extraction pipes may be located on a floor of a compartment or enclosure. The extraction pipes may be associated with a blower or fan that may be configured to draw air across one or more sensors. The enclosure may include a ventilation system that may be configured to maintain an air-exchange relationship to reduce the likelihood or probability of pockets of vapor developing. The ventilation system includes a blower or fan, separate from the blower or fan associated with the extraction pipes, to facilitate the air-exchange relationship.

BRIEF DESCRIPTION OF THE DISCLOSURE

According to one aspect of the disclosure, a system comprises a ventilation unit configured to exhaust drawn-in air from an enclosure, and a detection unit integrated with the ventilation unit and configured to detect a vapor.
According to another aspect of the disclosure, an apparatus comprises a collection mechanism configured to collect liquid, a detection unit configured to sample vapor emitted from the liquid of the collection mechanism, and a ventilation unit integrated with the detection unit and configured to exhaust the vapor subsequent to the vapor having been sampled by the detection unit.
According to yet another aspect of the disclosure, a method comprises collecting liquid in a collection mechanism, detecting, by a detection unit, vapors emitted from the collected liquid, and exhausting, via a ventilation unit integrated with the detection unit, drawn-in air mixed with the vapors from an enclosure.
These and other advantages and features will become more apparent from the following description taken in conjunction with the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The subject matter is particularly pointed out and distinctly claimed in the claims at the conclusion of the specification. The foregoing and other features of the disclosure are apparent from the following detailed description taken in conjunction with the accompanying drawings in which:

FIG. 1 illustrates an exemplary system in accordance with one or more aspects of the disclosure; and

FIG. 2 illustrates an exemplary method in accordance with one or more aspects of the disclosure.

The detailed description explains embodiments of the disclosure, together with advantages and features, by way of example with reference to the drawings.

DETAILED DESCRIPTION OF THE DISCLOSURE

In accordance with various aspects of the disclosure, apparatuses, systems and methods are described for detecting vapor, such as vapor associated with a gas. While largely stated in terms of vapor associated with fuel, the techniques and methodologies described herein may be adapted to accommodate other forms of detection. For example, aspects of the disclosure are directed to a detection of smoke.
It is noted that various connections are set forth between elements in the following description and in the drawings (the contents of which are included in this disclosure by way of reference). It is noted that these connections in general and, unless specified otherwise, may be direct or indirect and that this specification is not intended to be limiting in this respect. In this regard, a coupling of entities may refer to either a direct or an indirect connection.
FIG. 1 illustrates a system 100 in connection with one or more embodiments. The system 100 may be used to detect vapor, such as vapor associated with one or more fuels. The vapor may be the result of an evaporation process with respect to, e.g., leaking liquid fuel. The leak may be the result of, e.g., a poor or inadequate mechanical coupling between connection points or joints used in an application, such as a gas turbine application.
In some embodiments, the system 100 comprises an enclosure 101. In some embodiments, the enclosure 101 is used to contain liquid, such as leaking liquid. Optionally, the enclosure 101 is used to provide a closed environment for the liquid and any vapors that may be generated by the liquid.
In some embodiments, the system 100 comprises one or more dampers 102, such as dampers 102 a and 102 b. While two dampers 102 are shown in FIG. 1, the system 100 may include any number of dampers 102.
In some embodiments, the dampers 102 are associated with a ventilation mechanism or system that optionally is configured to provide for air-intake, cooling, or dilution. For example, the ventilation system may maintain temperatures in the system 100, so as to reduce the likelihood or probability of pockets of vapor developing. While not shown in FIG. 1, in some embodiments a controller is configured to control the dampers 102 to achieve a specified rate or volume of air-intake, air temperature, etc., with respect to the system 100.
In some embodiments, the system 100 comprises one or more pumps 104, such as pumps 104 a and 104 b. While two pumps 104 are shown in FIG. 1, the system 100 may include any number of pumps 104.
In some embodiments, the pumps 104 are configured to transfer liquid, such as liquid contributing to a leak, to a collection mechanism 106 via a flooring 108. In some embodiments, the pumps 104 are configured to return liquid (e.g., fuel) to, e.g., a gas turbine, for continued use.
In some embodiments, the flooring 108 is associated with a “false” flooring. Optionally, the flooring 108 comprises one or more penetration points or openings. In some embodiments, the openings allow liquid to fall through or penetrate the flooring 108 and to collect in the collection mechanism 106. In some embodiments, a series of openings are provided for. In some embodiments, the openings are configured to collect vapor from areas of the flooring 108, such as all areas of the flooring 108. In some embodiments, Computational Fluid Dynamics (CFD) code, such as CFX or Fluent, may be used.
In some embodiments, the flooring 108 has a uniform pressure drop. The uniform pressure drop may be used to ensure an effective capture velocity over the entire floor 108.
In some embodiments, the collection mechanism 106 comprises a sump. In some embodiments, the collection mechanism 106 is configured to receive liquid from the flooring 108 via the openings. The liquid may be stored, either temporarily or permanently, in the collection mechanism 106. In some embodiments, the collection mechanism 106 is used to ensure that liquid is contained in a closed environment. For example, the collection mechanism 106 may be used to capture, e.g., all liquids. In some embodiments, liquid contained in the collection mechanism 106 is returned to, e.g., a gas turbine, for use, or is disposed of
Liquid contained in the collection mechanism 106 may emit one or more vapors 110. The vapors 110 may be generated as a result of an evaporation of the liquid contained in the collection mechanism 106. In some embodiments, the vapors 110 are indicative of a gas that is heavier than air. In some embodiments, the vapors 110 are indicative of a gas that is lighter than air.
In some embodiments air 112 is extracted, possibly as part of a ventilation mechanism or system as previously described. The air 112 may serve a number of functions. In some embodiments the air 112 is inserted or forced below the flooring 108 by, e.g., a negative pressure ventilation system, in order to facilitate an air-exchange relationship to reduce the likelihood or probability of pockets of vapor 110 from developing.
In some embodiments, one or more blowers or fans are included. For example, one or more fans 114 may be used to draw the vapors 110 (potentially mixed with air 112) across or proximate to a detection unit 116 and subsequently out of the system 100 via an exhaust output or line 118. In this manner, in some embodiments the fan 114 functions as both a sample-draw fan (e.g., with respect to the detection unit 116) as well as a ventilation fan (e.g., with respect to the dampers 102 and/or the exhaust output or line 118). More generally, aspects of the disclosure may integrate a detection system and a ventilation system. As a result of such integration, a reduction in the number of components (e.g., fans or blowers) optionally is realized. The savings or reduction in components may be even greater when one considers that multiple components may (have) be(en) used in order to provide redundancy.
In some embodiments, the detection unit 116 comprises one or more sensors. Optionally, the sensors are configured to detect a presence and/or an amount of one or more gases based on the vapors 110, and potentially the air 112, being directed from the collection mechanism 106 towards the detection unit 116 via the fan 114.
In some embodiments, the detection unit 116 is configured to provide a status regarding the one or more gases. For example, if the amount of a detected gas (potentially measured as a volume, a concentration, etc.) exceeds a threshold, the detection unit 116 may generate a message. The message may take the form of an email, a text message, a voice message, a display graphic, an auditory alarm, etc. In some embodiments, when the amount of the detected gas exceeds a threshold, a determination may be made by, e.g., the detection unit 116 that a leak is present.
In some embodiments, the detection unit 116 causes measurements taken by the sensor(s) to be saved or stored, potentially in one or more memories, databases, etc. In some embodiments, a saving/storing of the measurements is used for data-logging purposes, in connection with troubleshooting, repair, or maintenance activities, to generate one or more reports, to provide any other opportunity for analysis, etc.
In some embodiments, the system 100 comprises one or more baffles 120, such as baffles 120 a and 120 b. While two baffles 120 are shown in FIG. 1, the system 100 may include any number of baffles 120.
In some embodiments, the baffles 120 are configured to control or regulate a flow of fluid in the system 100. In some embodiments, the baffles 120 are used to restrain the flow of vapors 110 and/or liquid in the collection mechanism 106. The baffles 120 may be used to control the flow of fluid in a given direction, such as toward the detection unit 116.
In some embodiments, the system 100 comprises one or more isolation mechanisms. For example, in some embodiments a valve 122, when in an “open” state or position, is used to drain liquid from the collection mechanism 106 by way of a drain outlet 124. The valve 122, when in a “closed” state or position, might not allow liquid to leave the collection mechanism 106 via the drain outlet 124. In some embodiments, the valve 122 is normally closed, but might be opened in the event of, e.g., a sizable leak (e.g., a leak beyond a threshold).
In some embodiments, the state or position of the valve 122 is manually commanded. For example, the state or position of the valve 122 may be responsive to a user input (e.g., depression of a switch, button, or key, a voice command, etc.). In some embodiments, the state or position of the valve 122 may be automatically determined by an entity, such as the detection unit 116. In some embodiments, the detection unit 116 is configured to command the valve 122 to open when the amount of the vapor 110 exceeds a threshold and to close when the amount of the vapor 110 is less than that threshold. In some embodiments, hysteresis may be applied to the threshold in order to avoid excessively opening and closing the valve 122 within a given period of time when the amount of the vapor 110 is proximate the threshold.
FIG. 2 illustrates a method that may be used in connection with one or more embodiments. The method of FIG. 2 may execute in conjunction with one or more systems, apparatuses, devices, or components, such as those described herein. In some embodiments, the method of FIG. 2 is used to detect that one or more gases are present. For example, the method may be used to detect that one or more gases are present in an amount exceeding a threshold, which may serve as an indication that there is a leak in connection with an associated application or system. In this regard, in some embodiments the method of FIG. 2 is used to monitor for a leak.
In step 202, liquid is collected. The liquid may be collected in one or more collection mechanisms, such as the collection mechanism 106. The liquid may be indicative of a leak associated with, e.g., a turbine.
In step 204, air is drawn through a floor of an enclosure, such as enclosure 101. For example, in some embodiments a negative pressure ventilation system that is coupled to a volume below a floor (e.g., floor 108) draws air from the enclosure via openings in the floor.
In step 206, a fan or blower (e.g., fan 114) causes vapors (e.g., the vapors 110) emitted from the collected liquid associated with step 202 to be detected by one or more detection units (e.g., detection unit 116), possibly in combination with the drawn-in air of step 204. As part of step 206, the fan/blower may also output or exhaust the vapors and/or drawn-in air after having been exposed to the detection unit (e.g., after having been sampled by the detection unit). A portion of the vapors and/or drawn-in air may be collected for analysis or examination.
In step 208, a measurement of one or more parameters based on the vapors and/or air associated with step 206 is conducted. For example, the detection unit may compare an amount of the vapors to one or more thresholds. Based on the comparison, in some embodiments the detection unit causes one or more actions to be taken. For example, the detection unit may: cause a regulation of a flow rate or speed of the fan/blower, provide for a state of one or more baffles (e.g., baffles 120), provide for a state or position of an isolation mechanism (e.g., valve 122) associated with the collection mechanism, generate one or more messages, etc.
The method of FIG. 2 is illustrative. In some embodiments, some of the steps (or portions thereof) are optional. In some embodiments, additional steps not shown are included. In some embodiments, the steps execute in an order or sequence different from what is shown in FIG. 2.
Aspects of the disclosure have been described in terms of the collection, sampling, and testing of vapors that may be given off during the evaporation process of one or more liquids, such as liquid that may be heavier or denser than air. One skilled in the art will appreciate that aspects of the disclosure may be adapted to accommodate different types of products, such as different types of liquids. For example, the techniques described herein may be applied in connection with gas turbines where naphtha may be used as a combustion fuel. Additional applications are within the scope and spirit of the disclosure.
As described herein, in some embodiments various functions or acts may take place at a given location and/or in connection with the operation of one or more apparatuses, systems, or devices. For example, in some embodiments, a portion of a given function or act may be performed at a first device or location, and the remainder of the function or act may be performed at one or more additional devices or locations.
Aspects of the disclosure may be implemented using one or more technologies. In some embodiments, an apparatus or system comprises one or more processors and memory storing instructions that, when executed by the one or more processors, cause the apparatus or system to perform one or more methodological acts as described herein. Various mechanical components are used in some embodiments.
In some embodiments, aspects of the disclosure are implemented as one or more apparatuses, systems, and/or methods. In some embodiments, instructions are stored on one or more computer-readable media, such as a transitory and/or non-transitory computer-readable medium. In some embodiments, the instructions, when executed, cause an entity (e.g., an apparatus or system) to perform one or more methodological acts as described herein.
In some embodiments, aspects of the disclosure are tied to particular machines. For example, as described herein, an enclosure optionally comprises a floor configured to pass liquids to a collection mechanism, such as a sump. In some embodiments, a ventilation mechanism, such as a negative pressure ventilation system, is configured to draw air from the enclosure through the floor. A mixture of air and vapor may then be conveyed through a ventilation mechanism via one or more fans or blowers. In some embodiments, one or more detectors is located within, e.g., a ducting. In some embodiments, the detector(s) is/are configured to detect the presence or amount of one or more gases evaporated off of the liquid collected in the collection mechanism. Optionally, the detected gas(es) is/are used to determine whether a leak is present.
In some embodiments, gas detection is provided for gases that are heavier than air. In some embodiments, an improved leak detection resolution is realized. For example, relatively small leaks may be detected, even if those leaks are not proximate an opening of an extraction pipe.
While aspects of the disclosure have been described in detail in connection with only a select number of embodiments, it should be readily understood that the disclosure is not limited to such embodiments. Rather, the disclosure 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 disclosure. Additionally, while various embodiments of the disclosure have been described, it is to be understood that aspects of the disclosure may include only some of the described embodiments. Accordingly, the disclosure is not to be seen as limited by the foregoing description, but is only limited by the scope of the appended claims.

Claims

1. A system comprising:

a ventilation unit configured to exhaust drawn-in air from an enclosure; and

a detection unit integrated with the ventilation unit and configured to detect a vapor.

2. The system of claim 1, where the vapor is associated with evaporation of a liquid contained in a closed environment.

3. The system of claim 2, wherein the closed environment is at least partially defined by a floor comprising openings configured to drain the liquid into a collection mechanism.

4. The system of claim 1, wherein the detection unit is integrated with the ventilation unit via a common fan or blower.

5. The system of claim 1, wherein the vapor is heavier than air.

6. The system of claim 1, wherein the vapor comprises smoke.

7. The system of claim 1, wherein the detection unit is configured to cause an action to be taken when an amount of the vapor exceeds a threshold.

8. The system of claim 1, further comprising:

at least one damper configured as an inlet for the drawn-in air.

9. The system of claim 1, wherein the ventilation unit is configured to exhaust the vapor after the vapor is sampled by the detection unit.

10. The system of claim 1, further comprising:

an outlet; and

an isolation mechanism configured to selectively transfer liquid associated with the vapor from a collection mechanism to the outlet.

11. The system of claim 10, wherein the isolation mechanism comprises a valve, and wherein a position of the valve is determined by the detection unit.

12. An apparatus comprising:

a collection mechanism configured to collect liquid;

a detection unit configured to sample vapor emitted from the liquid of the collection mechanism; and

a ventilation unit integrated with the detection unit and configured to exhaust the vapor subsequent to the vapor having been sampled by the detection unit.

13. The apparatus of claim 12, wherein the ventilation unit comprises:

at least one damper configured as an inlet for drawing-in air.

14. The apparatus of claim 13, further comprising:

a floor configured to allow the liquid to fall through the floor and to collect in the collection mechanism; and

a negative pressure ventilation system configured to provide the air to a volume below the floor via at least one opening or a series of openings which are configured so as to collect vapor from all areas of the floor.

15. The apparatus of claim 12, wherein the detection unit is integrated with the ventilation unit via a common fan or blower.

16. The apparatus of claim 12, wherein the detection unit comprises at least one sensor configured to detect the vapor.

17. The apparatus of claim 16, wherein the detection unit is configured to generate a message when the vapor exceeds a threshold, and wherein the message comprises at least one of: an email, a text message, a voice message, a display graphic, and an auditory alarm.

18. A method comprising:

collecting liquid in a collection mechanism;

detecting, by a detection unit, vapors emitted from the collected liquid; and

exhausting, via a ventilation unit integrated with the detection unit, drawn-in air mixed with the vapors from an enclosure.

19. The method of claim 18, wherein the detection unit is integrated with the ventilation unit via a common fan or blower.

20. The method of claim 18, wherein the enclosure is coupled to a turbine, and wherein the liquid comprises naphtha leaked by the turbine.