CONTAMINANT PLUME

FIELD OF THE INVENTION

The present invention relates generally to air contaminant plume interrogation, and more particularly to a means for remotely assessing air pollutant presence and concentration within an air contaminant plume.

BACKGROUND OF THE INVENTION

Owing to escalating global and local environmental concerns, an impasse has developed between the convenience and cost-effectiveness of processing industry and the obligations placed on companies to comply with increasingly stringent regulatory and safety requirements. This situation is further compounded by overarching governmental objectives to ubiquitously reduce emission levels within relatively short timescales.

Notably one of the easiest approaches for companies to take in view of complying with their emission targets and, thus, fulfilling their regulatory obligations, is to institute rigorous gas leak detection and monitoring provisions. Indeed, gas leak detection has been identified and named by the US Environmental Protection Agency (EPA) as the single most effective approach for complying with existing regulatory provisions. One such tool for gas leak detection, which has been explicitly endorsed by the EPA following extensive research and comparisons with traditional technologies, is optical gas imaging (OGI). OGI is a modern thermal imaging technology that utilizes high-sensitivity infrared cameras to detect fugitive industrial gas emissions.

OGI has developed rapidly over recent years and has now become one of the leading established technologies for gas leak detection. As a standalone provision, however, OGI functions only to image gas leaks and thus lacks the requisite functionality to interrogate in detail the content and concentration of a gas leak. A greater level of detail is however highly desirable as such information may be used to characterize the source composition, concentration, and emission rate of an identified air contaminant emission plume.

However, when trying to characterize and analyze the content of air toxics within a plume of a combustion source for example, OGI cannot provide an efficient solution. Currently, the characterization and analysis of air pollutant plumes is carried out by people climbing stacks and or elevated vents where samples are taken in an inefficient and sometimes dangerous manner. SUMMARY OF THE PRESENT INVENTION

In order to address the drawbacks of the prior art, some embodiments of the present invention provide an air pollution and emission characterization system and method. The disclosed invention can characterize and analyze any industrial air polluting, gas and particulate matter, either with global impact, for example in accordance with the greenhouse (GHG) protocol, as well as local health impact, including, but not limited to pollutant from combustion sources or industrial leaks and emissions of non-combustion sources such as process units, storage tanks and the like.

In accordance with some embodiment of the present invention, a system for tracking and analyzing an air contaminant plume is disclosed herein. The system may include a stationary (separate from the mobile platform) optical gas imaging “OGI” camera configured to track the air contaminant plume and determine boundaries thereof; a mobile platform having an investigation module comprising at least one of: a sensor; and, a sampling device, the investigation module being operable to interrogate the air contaminant plume; and a control and processing unit configured to remotely issue control commands to the mobile platform to guide the mobile platform into a location proximate to or within the determined boundaries of the air contaminant plume and to operate the investigation module of the mobile platform; wherein the investigation module, upon the mobile platform arriving at the location, is operable to at least one of: (i) capture a sample of the air contaminant plume using the at least one sampling device and physically convey said sample to analyzer for analysis; and (ii) record real-time sensor data of the air contaminant plume using the at least one sensor and remotely transmit said data to the control and processing unit for analysis, or saving the data on the platform (data logger of some sort); and wherein the control and processing unit is configured to receive at least one of: said sample analyzed data; and, said real-time sensor data, from the investigation module of the mobile platform and thereupon conduct analysis to determine the presence and type of one or more air pollutants within the air contaminant plume and their respective concentrations.

In accordance with some embodiment of the present invention, a method for tracking and analyzing an air contaminant plume is also disclosed herein. The method comprises: tracking and determining the boundaries of the air contaminant plume using an optical gas imaging “OGI” camera; guiding a mobile platform having at least one of: a sensor; and, a sampling device, into a location proximate to or within the detected boundaries of the air contaminant plume through remotely issued control commands from a control and processing unit; interrogating the air contaminant plume responsive to remotely issued control commands from the control and processing unit by at least one of: (i) capturing a sample of the air contaminant plume using the at least one sampling device and physically conveying said sample to analyzer for analysis; and (ii) recording real-time sensor data of the air contaminant plume using the at least one sensor and remotely transmitting said data to the control and processing unit for analysis; and receiving at least one of: said sample analyzed data; and, said real-time sensor data at the control and processing unit, and thereupon conducting analysis to determine the presence and type of one or more air pollutants within the air contaminant plume and their respective concentrations.

These and other advantages of the present invention are set forth in detail in the following description.

BRIEF DESCRIPTION OF THE DRAWINGS

For a better understanding of the invention and in order to show how it may be implemented, references are made, purely by way of example, to the accompanying drawings in which like numerals designate corresponding elements or sections. In the accompanying drawings:

Figure 1 is a schematic diagram illustrating an exemplary non-limiting arrangement for tracking and analyzing an air contaminant plume using an airborne mobile platform according to embodiments of the invention;

Figure 2 is a schematic diagram illustrating an exemplary non-limiting arrangement for tracking and analyzing an air contaminant plume using a land-based mobile platform according to embodiments of the invention;

Figure 3 is a schematic diagram illustrating an exemplary non-limiting architectural arrangement of a system for tracking and analyzing an air contaminant plume according to embodiments of the invention; and

Figure 4 is a graphical flow diagram illustrating an exemplary method for tracking and analyzing an air contaminant plume according to embodiments of the present invention.

It will be appreciated that for simplicity and clarity of illustration, elements shown in the figures have not necessarily been drawn to scale. For example, the dimensions of some of the elements may be exaggerated relative to other elements for clarity. Further, where considered appropriate, reference numerals may be repeated among the figures to indicate corresponding or analogous elements. DETAILED DESCRIPTION OF THE INVENTION

With specific reference now to the drawings in detail, it is stressed that the particulars shown are for the purpose of example and solely for discussing the preferred embodiments of the present invention and are presented in the cause of providing what is believed to be the most useful and readily understood description of the principles and conceptual aspects of the invention. In this regard, no attempt is made to show structural details of the invention in more detail than is necessary for a fundamental understanding of the invention. The description taken with the drawings makes apparent to those skilled in the art how the several forms of the invention may be embodied in practice.

Before explaining the embodiments of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of the components set forth in the following descriptions or illustrated in the drawings. The invention is applicable to other embodiments and may be practiced or carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein is for the purpose of description and should not be regarded as limiting.

The following term definitions are provided to aid in construal and interpretation of the invention.

The terms “optical gas imaging” or “OGI” refer generally to thermal imaging technologies that utilize high-sensitivity infrared cameras to detect gas emissions. An “OGI” camera may typically include a lens, a detector, processing electronics and a viewfinder display for use by an operator to view images produced by the camera. “OGI” technologies are typically utilized to detect fugitive or undesirable gas emissions of, for example, methane and carbon dioxide, and work by capturing images from non-hazardous distances and presenting these images in a comprehensible format where typically invisible gases are translated into observable clouds or pockets of emissions, i.e. plumes.

The terms “volatile organic compounds” or “VOCs” refer generally to both anthropogenic and biogenic organic compounds with characteristically high vapor pressures while at room temperatures. “VOCs” are typically responsible for odor, scents and air pollutants and may, in some circumstances, be dangerous either to human health or the wider environment. Anthropogenic “VOCs” are typically generated by fossil fuel use, solvent use in coatings and paints, or biofuels and may include ethane and styrene. It should be noted herein in the context of the present invention, that an OGI can track a plume of VOCs or CO ₂ as tracer gas for the air contaminant plume so that the boundaries of the plume (of any tracer gas) is first traced and detected and then the other air contaminant is analyzed. The term “air contaminant plume” refer generally to a body of at least one air contaminant moves through air, imaged by the OGI camera. “Air contaminant plumes” may, for example, be seen by CO2 OGI camera emitted from combustions source such as coal power plant or emergency flares.

The term “tracer gas” is the gas detected and tracked by the OGI, typically CO2 for combustion sources and VOCs for Oil and Gas industry fugitive sources such as storage tanks and processing plant and units. The tracer gas is typically the primary component of the air contaminant plume.

The term “target air contaminant” is a gaseous compound or particulate matter (PM) analyzed by the investigation module either in real time by sensor or post analysis of captured sample by laboratory analyzer.

The terms “investigate”, “interrogate” and “probe” are used interchangeably herein to refer to an action taken, for example by an operator, in view of obtaining data from a variable source. More specifically, in the context of the present invention the system may seek to “interrogate” or “probe” an air contaminant plume, for example using sensing or sampling devices, in order to obtain further data regarding the content of air contaminant plume, such as the presence of one or more air pollutants and their respective concentrations.

The term “investigation module” as used herein relates to characterization and analysis module consist of real time sensors and sampling devices for obtaining concentration data for the target air contaminants. It may also include real time sensors for the tracer gas for verifying position of the mobile platform within the air contaminant plume.

The degree of tolerance within which optical gas imaging technology may be utilized to visualize and detect gas plumes, often referred to as the mass flow detection limit, has been found to vary in accordance with various factors including the distance between the OGI camera and an emission source and, importantly, the difference between a gas plume’s temperature and the temperature of its backdrop/background, as viewed through the OGI camera. For example, in circumstances where an OGI camera is positioned on the ground looking upwards in the direction of a gas plume, the backdrop would typically be the sky. Conversely, in circumstances where an OGI camera is positioned on an airborne vehicle flying above the gas plume, the backdrop would typically be the ground.

Figure 1 is a schematic diagram illustrating an arrangement 100 for tracking and analyzing an air contaminant plume using an airborne mobile platform according to embodiments of the invention. An air pollution emission source 10, which may be combustion source, storage tank, flare or the like, is found or known to be emitting an undesirable or problematic air contaminant plume 11 containing, for example, air contaminants carried in a carbon dioxide gas or VOCs. A land-based OGI camera 12 is therefore deployed and orientated such that the background to the air contaminant plume 11, when viewed by the OGI camera 12, has sufficient apparent temperature difference from the air contaminant plume’s temperature for the plume to be imaged. The OGI camera 12 is configured, for example by an operator, to track the tracer gas in the air contaminant plume 11 and determine its external boundaries. Images obtained by the OGI camera 12 may be transmitted 13, optionally in real-time, to a processing and control station 16 and may be viewed by, for example, an operator using a display 17. Responsive to the images obtained by the OGI camera 12, an airborne mobile platform such as drone 14 may be dispatched and guided, via remotely issued control commands from the processing and control unit/station 16, to fly to a location either proximate to, or within, the determined external boundaries of the air contaminant plume 11.

The drone 14 may be equipped with an investigation module having one or more sensing devices 15, such as a tunable diode laser absorption spectroscopy laser or a nondispersive infrared sensor or a photo ionization detector and alike, and may be operable, responsive to command controls issued by the processing and control station 16, to interrogate the air contaminant plume 11 by recording real-time sensor data about the air contaminant plume 11 and transmitting the acquired data to the control and processing station 16 for further analysis. The recorded data may comprise one or more of: compound concentration data, temperature data, and humidity data.

The investigation module of the drone 14 may also, or alternatively, be equipped with one or more sampling devices, such as a remote controllable adsorption tube, canister or Tedlar bag, and may be operable, responsive to control commands issued by the processing and control station 16, to grab a sample from the air contaminant plume 11 by capturing and retaining a sample of the air contaminant plume. This sample may then subsequently be physically conveyed, for example using the drone 24, to a laboratory (field or remote) equipped with relevant analyzers for post-analysis.

A remote or local lab with analyzers 18 may then be operable, upon receipt of the air contaminant plume samples, to conduct various analysis and/or data processing techniques, as would be known by those skilled in the art, to ascertain the presence and type of one or more air pollutants within the air contaminant plume 11 and the respective concentrations of each of the air pollutants or other derive property found to be present within the air contaminant plume 11. In some embodiment the emission source 10 may be a combustion source such as a coal fired power plant stack. The air contaminant plume 11 consists primarily of CO2 gas and the OGI camera 12 is configured to detect and track CO2. Typically, the investigation module will consist of sensors and sampling devices for quantifying concentration of air contaminants typical for combustion source emissions such as SOx NOx PM and alike.

In some embodiment the emission source 10 may be an emergency flare, a common practice in chemical industry and refineries. The air contaminant plume 11 consist primarily of CO2 gas and the OGI camera 12 is configured to detect and track CO2. Typically, the investigation module will consist of sensors and sampling devices for quantifying concentration of air contaminants typical for combustion efficiency assessment such as total VOCs, CO, PM, CO2, and the like.

In some embodiment the emission source 10 may be an oil refinery fugitive emission source such as a storage tank for crude oil or fuel products. The air contaminant plume 11 consist primarily of VOCs and the OGI camera 12 is configured to detect and track total VOCs. Typically, the investigation module will consist of sensors and sampling devices for quantifying concentration of air contaminants typical for fugitive source emissions such as total VOCs, 1,3 butadiene, benzene and alike.

In some embodiment the emission source 10 may be a natural gas source such as a well pad or processing plant. The air contaminant plume 11 consist primarily of methane (a VOC) gas and the OGI camera 12 is configured to detect and track VOCs. Typically, the investigation module will consist of sensors and sampling devices for quantifying concentration of air contaminants typical for a natural gas emission source such as methane, total VOCs, 1,3 butadiene, benzene and alike. For methane the sensor may include an open path sensor such as TDLAS measuring the whole column of methane concentration from the mobile platform to the ground.

Figure 2 is a schematic diagram illustrating an arrangement 200 for tracking and analyzing an air contaminant plume using a land-based mobile platform according to embodiments of the invention. Similarly to the embodiment in Figure 1, an air contaminant emission source 20 is found to be emitting an air contaminant/thermal plume 21 containing, for example, methane, carbon dioxide, carbon monoxide or a VOC. In this case, the air contaminant plume 21 has dispersed in such a manner that it falls somewhat at ground level and lies partially across a motorway 28. An OGI camera 22 is therefore deployed and configured, for example by an operator, to track the air contaminant plume 21 and determine its external boundaries. Although illustrated as a land-based OGI camera 22, it will be appreciated that the positioning of the air contaminant plume 21 may, in some circumstances such as these, be such that it is not possible to entirely orientate the OGI camera 21 with the sky as a backdrop to the air contaminant plume. Embodiments of the invention therefore also foresee circumstances where it may be expeditious and advantageous for the OGI camera 22 to instead be mounted on a tower or an airborne platform, looking down at the air contaminant plume and its background, notwithstanding the corresponding loss of sensitivity.

Images of the air contaminant plume 21 are duly obtained by the OGI camera 22 and transmitted 23, optionally in real-time, to a processing and control station/unit 26 and may be viewed by, for example, an operator using a display 27. Responsive to the images obtained by the OGI camera 22, a land-based vehicle 24 may be dispatched and guided, via remotely issued directions/coordinates from the processing and control station 26, to drive along the motorway 38 to a location either proximate to, or within, the determined external boundaries of the air contaminant plume 21.

The land-based vehicle 24 may, similarly to the airborne mobile platform 14, be equipped with one or more sensing devices, such as a tunable diode laser absorption spectroscopy laser or a nondispersive infrared sensor, and may be operated, either remotely or by the driver of the land- based vehicle 24, to interrogate the air contaminant plume 21 by recording real-time sensor data about the air contaminant plume 21 and transmitting the acquired data to the control and processing station 26 for further analysis. The recorded data may comprise one or more of: compound concentration data, temperature data, and humidity data.

The land-based vehicle 24 may also, or alternatively, be equipped with one or more sampling devices, such as an adsorption tube, canister or Tedlar bag, and may be operated, either remotely or by the driver of the land-based vehicle 24, to interrogate the air contaminant plume 21 to capture and retain a sample of the air contaminant plume. This sample may then subsequently be physically conveyed, for example using the land-based vehicle 24, to an analyzer in a local or remote lab 18 for analysis.

The control and processing station 26 may be operable, upon receipt of the air contaminant plume sample analyzed data and/or the real-time sensor data, to conduct various analysis and/or data processing techniques, as would be known by those skilled in the art, to ascertain the presence and type of one or more air pollutants within the air contaminant plume 31 and the respective concentrations of each of the air pollutants or other derive property found to be present within the air contaminant plume 21.

Figure 3 is a schematic diagram illustrating a system arrangement 300 for tracking and analyzing an air contaminant plume according to embodiments of the invention. The system 300 may include an OGI camera 321 having at least one capturing component 32 operable to capture images lying along a field of view denoted by capturing direction 323. In some embodiments, the OGI camera 321 may be operated autonomously, either wholly or in part, according to inbuilt computer processing logic. Alternatively, the OGI camera 321 may be operated responsive to operator 39 controls which may be input, for example, using user interface 38. The capturing component 32 may be interconnected with a gimbal, or the like, and may be repositioned, thereby varying the capturing direction 323 of the capturing component 32, using a pan-tilt-zoom (PTZ) module 324. Command controls generated either by the computer processing logic or input via the user interface 38 may accordingly include instructions for the PTZ module 324 to implement. Images captured by the OGI camera 321 may be transmitted, either through wired or wireless means, to data streaming module 361 in processing and control unit 36. The data streaming module 361 may transfer these images, optionally in real-time, to a display device 37 for viewing by the operator 39.

The system 300 may further include a mobile platform 341, such as a drone 34 or land-based vehicle (not shown), having one or more sensors and/or one or more sampling devices 342. The mobile platform 341 may be controlled remotely by an operator 39 in accordance with control commands issued via the platform control 362 and sensor/sampler control 362 modules of the processing and control unit 36. These control commands may, for example, be input by the operator 39 using user interface 38 responsive to data (e.g., coordinate and altitude data) streamed wirelessly from the mobile platform 341. Data obtained by the one or more sensors 342 may be streamed, optionally in real-time, to the raw sensor data module 364 of the processing and control unit 36. A data analysis module 365 is also included and may be configured to collate data from the raw sensor data module 364, along with any data obtained from air contaminant samples obtained by the mobile platform 341, and implement various processing and analysis techniques and algorithms, as would be known by those skilled in the art. A data characterization module 366 may then be employed to identify trends and format results from the data analysis module 365 and, optionally, present these results to the operator 39 via display 37.

Figure 4 is a graphical flow diagram illustrating an exemplary method for tracking and analyzing an air contaminant plume according to an embodiment of the invention. Method 400 may include the steps of: tracking and determining the boundaries of the air contaminant plume using an optical gas imaging camera 410; guiding a mobile platform into a location proximate to or within the detected boundaries of the air contaminant plume through remotely issued control commands 420; interrogating the air contaminant plume responsive to remotely issued control commands to obtain interrogation data 430; and, conducting analysis upon the interrogation data to determine the presence and type of one or more air pollutants within the air contaminant plume and their respective concentrations 440. According to some embodiments, the OGI camera may be located on the ground and may face upwards in the direction of the air contaminant plume with the sky as a background.

According to some embodiments, the OGI camera may be operable to track and determine the boundaries of an air contaminant plume originating from an emission source.

According to some embodiments, the air pollutant may include one or more of: methane; carbon dioxide; and, a volatile organic compound “VOC”.

According to some embodiments, the control and processing unit may be further configured to receive a stream of real-time video images from the OGI.

According to some embodiments, the mobile platform may be a drone or land-based vehicle. According to some embodiments, real-time sensor data recorded by the at least one sensor may comprise one or more of: compound concentration data; temperature data; and, humidity data. According to some embodiments, the at least one sampling device may comprise at least one of: a remote controllable adsorption tube; a remote controllable canister; and, a remote controllable Tedlar bag.

According to some embodiments, a plurality of OGI cameras may be utilized and positioned in different locations, wherein the plurality of OGI cameras may be collectively operable, in conjunction with the control and processing unit, to triangulate and track the mobile platform proximate to or within the detected boundaries of air contaminant plume.

According to some embodiments, one or more wind monitors may be utilized to determine wind speed, each having at least one wind speed sensor.

The aforementioned flowchart and diagrams illustrate the architecture, functionality, and operation of possible implementations of systems, methods and computer program products according to various embodiments of the present invention. In this regard, each portion in the flowchart or portion diagrams may represent a module, segment, or portion of code, which comprises one or more executable instructions for implementing the specified logical function(s). It should also be noted that, in some alternative implementations, the functions noted in the portion may occur out of the order noted in the figures. For example, two portions shown in succession may, in fact, be executed substantially concurrently, or the portions may sometimes be executed in the reverse order, depending upon the functionality involved, It will also be noted that each portion of the portion diagrams and/or flowchart illustration, and combinations of portions in the portion diagrams and/or flowchart illustration, can be implemented by special purpose hardware -based systems that perform the specified functions or acts, or combinations of special purpose hardware and computer instructions.

As will be appreciated by one skilled in the art, aspects of the present invention may be embodied as a system or an apparatus. Accordingly, aspects of the present invention may take the form of an entirely hardware embodiment or an embodiment combining software and hardware aspects that may all generally be referred to herein as a “circuit,” “module” or “system.”

The aforementioned figures illustrate the architecture, functionality, and operation of possible implementations of systems and apparatus according to various embodiments of the present invention. Where referred to in the above description, an embodiment is an example or implementation of the invention. The various appearances of “one embodiment,” “an embodiment” or “some embodiments” do not necessarily all refer to the same embodiments. Although various features of the invention may be described in the context of a single embodiment, the features may also be provided separately or in any suitable combination. Conversely, although the invention may be described herein in the context of separate embodiments for clarity, the invention may also be implemented in a single embodiment. Reference in the specification to “some embodiments”, “an embodiment”, “one embodiment” or “other embodiments” means that a particular feature, structure, or characteristic described in connection with the embodiments is included in at least some embodiments, but not necessarily all embodiments, of the inventions. It will further be recognized that the aspects of the invention described hereinabove may be combined or otherwise coexist in embodiments of the invention. It is to be understood that the phraseology and terminology employed herein is not to be construed as limiting and are for descriptive purpose only.

The principles and uses of the teachings of the present invention may be better understood with reference to the accompanying description, figures and examples.

It is to be understood that the details set forth herein do not construe a limitation to an application of the invention.

Furthermore, it is to be understood that the invention can be carried out or practiced in various ways and that the invention can be implemented in embodiments other than the ones outlined in the description above.

It is to be understood that the terms “including”, “comprising”, “consisting” and grammatical variants thereof do not preclude the addition of one or more components, features, steps, or integers or groups thereof and that the terms are to be construed as specifying components, features, steps or integers.

If the specification or claims refer to “an additional” element, that does not preclude there being more than one of the additional element.

It is to be understood that where the claims or specification refer to “a” or “an” element, such reference is not be construed that there is only one of that element. It is to be understood that where the specification states that a component, feature, structure, or characteristic “may”, “might”, “can” or “could” be included, that particular component, feature, structure, or characteristic is not required to be included.

Where applicable, although state diagrams, flow diagrams or both may be used to describe embodiments, the invention is not limited to those diagrams or to the corresponding descriptions. For example, flow need not move through each illustrated box or state, or in exactly the same order as illustrated and described.

Methods of the present invention may be implemented by performing or completing manually, automatically, or a combination thereof, selected steps or tasks.

The term “method” may refer to manners, means, techniques and procedures for accomplishing a given task including, but not limited to, those manners, means, techniques and procedures either known to, or readily developed from known manners, means, techniques and procedures by practitioners of the art to which the invention belongs.

The descriptions, examples and materials presented in the claims and the specification are not to be construed as limiting but rather as illustrative only.

Meanings of technical and scientific terms used herein are to be commonly understood as by one of ordinary skill in the art to which the invention belongs, unless otherwise defined.

The present invention may be implemented in the testing or practice with materials equivalent or similar to those described herein.

While the invention has been described with respect to a limited number of embodiments, these should not be construed as limitations on the scope of the invention, but rather as exemplifications of some of the preferred embodiments. Other or equivalent variations, modifications, and applications are also within the scope of the invention. Accordingly, the scope of the invention should not be limited by what has thus far been described, but by the appended claims and their legal equivalents.