Exelis' Enhanced Visualization Tools Accelerate Better Decision Making - The ANGEL System

Exelis delivers industry-leading imagery that enhances the safety and profitability of natural gas operations

For operators of underground transmission pipelines and/or aboveground natural gas processing facilities, finding and fixing “fugitive emission” leaks continues to be a business-critical task for safety, environmental stewardship, preservation of a finite resource and revenue enhancement. And for those engaged in natural gas exploration, finding and capturing methane emissions from naturally occurring underground sources is motivated by profit potential in addition to the reasons above.

The question is: How can the process of finding leaks, emissions and seeps – and taking action on those findings – be accelerated? Increasingly, industry leaders in each of these segments are turning to ITT (now Exelis, Inc,) for the enhanced leak and seep detection and visualization tools needed to inform and guide critical business decisions in real time.

Visualizing Natural Gas Transmission Pipeline Leaks… Before Ruptures Occur

To address this ongoing challenge, ITT Corporation developed Airborne Natural Gas Emission Lidar (ANGEL) Services, delivering a safe and cost-effective way to aerially survey extensive networks of underground pipelines for leaks, while still maintaining a high level of accuracy and sensitivity. In the context of transmission pipeline surveys, ANGEL Services combines the speed, efficiency and practicality of an aerial visual patrol with the confidence of an instrumented leak survey.

With a growing recognition that walking transmission pipelines in search of leaks is both time-consuming and prone to missing leaks, the industry’s more progressive transmission pipeline operators have increasingly been turning to the advanced leak detection and visualization services provided by ITT. One such firm is Northern Natural Gas (NNG), headquartered in Omaha, Nebraska.

NNG recognized the daunting task of walking its pipelines to fulfill its periodic pipeline leak survey requirements to satisfy U.S. Department of Transportation regulations and selected ITT to perform aerial leak surveys over a specific pipeline segments. In the words of Jeff Cullison, regional pipeline specialist, the decision to use ITT was “based on proven accuracy as well as the short time duration to cover the network.”

On one particular survey flight over this particular NNG segment, ITT detected a new underground leak indication. Based on the data collected, NNG was presented with the exact spatial location and plume visualization of a major underground pipeline leak, as seen below. Upon investigation, the leak that ITT had found represented a serious safety concern. “This crack probably wouldn’t have been discovered for another year, when the pipeline was next scheduled for inspection,” said Cullison. “Or, it would have split open.” But through use of ITT’s tools a pipeline integrity issue was quickly identified and a potential disaster was averted.

This customer deliverable imagery visualizes:

• Methane gas detection and location

• Gas concentration in ppm-m

• Gas concentration contour mapping

• Location and context of buried gas pipeline centerline

• Color right-of-way mapping imagery, showing nearby structures and roadway

•Differential Absorption Laser (DIAL) scan swath (the “blue ribbon”)

Visualizing Fugitive Infrastructure Emissions at Natural Gas Processing Facilities

Just as with natural gas transmission pipelines, operators of natural gas facilities – such as compressor stations, gas-processing operations, etc. – must perform leak and emission surveys on each facility’s infrastructure on a periodic basis. And while traditional methods of ground-based leak detection at facilities are time-consuming and prone to missing leaks, the reason many facility leaks are not detected differs from the reason walking surveys fail to detect underground pipeline leaks.

Equipment and infrastructure on gas processing facilities often rise dozens of yards into the air, including tanks, stacks, evaporators, condensers and so on. This infrastructure can deteriorate and begin to leak at any height, not just at ground level or even within reach of ground-based equipment and personnel. ITT’s ANGEL Services provides an aerial leak survey that measures methane above background levels from the belly of the airplane all the way down to the ground. And ITT’s visualization tools enable facility operators to precisely determine the spatial location of fugitive emissions - including a two-dimensional visualization of a three-dimensional gas plume - even when those emissions are far above the ground and the reach of traditional equipment.

One natural gas transmission customer in particular that has contracted with ITT for airborne leak detection surveying is El Paso Corporation, specifically on its Tennessee Gas Pipeline (TGP) network. In late 2008, ITT detected an emission on a TGP facility and provided the pinpoint leak location and visual imagery to support the find. Understanding that finding leaks on a facility can be a tricky task, Martin Melchor, principal analyst/compliance services director for El Paso Corporation, said, “What we’re looking for is fugitive gas emissions that occur where we might not be able to see them.”

Facility operators are driven to find and fix leaks for the same reasons as underground pipelines: safety, environmental stewardship and financial responsibility. Anders Johnson, director of planning and gas control for TGP, said, “It’s still not acceptable to have that loss of natural gas – from the environmental aspects and our fiduciary responsibility to those we’re delivering gas to.” Given methane’s physical properties, finding leaks can be challenging. “It’s clear – if you have a leak, many times you can’t see it,” echoed Johnson. ITT’s customer deliverables (see inset) show the spatial location and plume visualization of the facility emission that ANGEL Services detected, including a quantified methane concentration contour map.

Visualizing Methane Emission Sources for Natural Gas Exploration

In the area of natural gas exploration, coalbed methane is a prevalent source of naturally occurring methane gas that literally seeps out of the ground and into the atmosphere. Underground methane permeates natural coal formations and escapes in varying areas based on the geology of the terrain, changes to the water table and other activities that contain or release the trapped gas. Before the escaping gas can be captured for safety, environmental or revenue reasons, the exact location of those seeps must be found. Often these seeps are located across great expanses of rugged terrain affected by severe weather conditions.

One progressive organization that has contracted with ITT to exhaustively locate coalbed methane seeps is the Southern Ute Indian Tribe (SUIT), with landholdings in southern Colorado on a geologic formation named the Fruitland Outcrop. Historically, the SUIT employed ground-based walking survey teams to collect ground gas samples across this nearly 90-square-mile parcel of land. However, the sheer size of the area, difficult terrain and necessity of limited sampling meant not all methane seeps could be identified.

With private residences and commercial enterprises scattered throughout the Fruitland Outcrop, the safety of residents and visitors alike have motivated the SUIT to seek the best possible information on methane seep locations across their landholdings, including public lands. Secondly, the capture and sale of methane is a strong source of revenue for the SUIT. Thirdly, the capping of emission sources for future production is also an important environmental stewardship activity; as a greenhouse gas, methane has 20 times the warming potential of CO2.

In just a few weeks of actual flying time, ITT’s ANGEL Services was able to survey the entire Fruitland Outcrop using its Cessna Caravan-mounted Differential Absorption Lidar (DIAL) sensor. An unprecedented approach to methane seep detection, ITT’s 100 percent ground survey coverage gave the SUIT the confidence that no emission source was missed, thus satisfying their need for the utmost in safety and environmental stewardship.

ITT’s fusion of airborne emission survey data with the mapping imagery solution allowed the SUIT to clearly see the locations, intensity, characterization and direction of the gas plumes created by the escaping methane. With this critical information, the SUIT could now prioritize the seep areas that would be capped for safety, along with those that would be capped for future gas production activity.

In the words of Kyle Siesser, SUIT geologist, “The work ITT performed has provided the first ‘snap-shot’ of seep conditions along the entire Fruitland Outcrop in Colorado.” Bill Flint, SUIT senior petroleum engineer, offered a similar sentiment: “The aerial mapping enabled us to visualize these seeps and plumes for the first time, giving us a unique perspective on what was happening at ground level. They (ITT) found a number of seep areas that we didn’t know we had.”

ITT ANGEL Services - Delivering Next-generation Detection and Visualization Tools for Natural Gas Operators

ITT’s ANGEL Services employs a proprietary multimodal sensor payload designed to capture data and images as it performs airborne emission and leak surveys. The onboard Differential Absorption Lidar (DIAL) sensor detects gas leaks and the system also captures photo imagery from both a high-resolution mapping camera and a color digital video camera that helps operators verify leak and emission indications. But advanced data visualization, data fusion and image analysis technology are behind the true success of the ANGEL Services reporting system.

The custom software used to analyze and visualize ANGEL Services data was developed using software products from ITT including IDL, an advanced computing environment for data visualization and analysis, and ENVI, a leading software solution for image processing and analysis. The custom software allows the ITT to provide customers with visualized gas concentration levels and contours within a georeferenced spatial image, yielding accurate, near real-time reporting of potential leak sources.

The final ITT customer deliverable is a leak/emission survey report that clearly indicates the locations of higher-than-normal concentrations of methane, or “hot spots,” on a high-resolution photo image of the area. Those results are registered with existing geospatial data in the pipeline area of interest – such as the pipeline centerline – to create a final geo-referenced data product – ensuring a high level of leak / emission survey accuracy for reporting and mapping purposes. This integration allows natural gas operators to easily import, select and analyze the results within their enterprise Geographic Information Systems in support of integrity management regulation compliance, asset management and hazard notification. This data and imagery integration enables more timely and effective decisions in managing pipeline assets and safety.

For natural gas transmission pipeline operators, facility operators and those in gas exploration, ITT’s unique detection method and specialized analysis, reporting and visualization software, provides customers with a revolutionary way to ensure safety, to protect the environment, to comply with regulations and to more effectively utilize personnel along their pipelines and operations.

 

Click on the thumbnails for more information.
[LIGHTBOXCONTENTGALLERY:6345] [LIGHTBOXCONTENTGALLERY:6439]