Technology

After years of research and development, we have created an airborne gas detector that is rugged enough for the tough industrial environment, and yet sufficiently sensitive to detect even the smallest pipeline leaks. This unique system allows us to offer what is now known as the best aerial leak detection service in the industry.

Principle of operation

Technically speaking, LASEN’s Airborne Lidar Pipeline Inspection Service (ALPIS™) is based on a mid-infrared Differential Absorption Lidar (DIAL) chemical sensor. The principle of DIAL relies on the selective absorption of laser light by different chemicals. The mid- infrared laser used in the ALPIS™ system is particularly well suited for detection of hydrocarbons such as methane, ethane, as well as volatilized liquid petroleum products, such as benzene. In operation, the laser beam is transmitted down from the aircraft to illuminate the area on the ground above and around the buried pipe. The light reflected from the ground is collected by the sensor’s receiver, and the amount of received energy is measured. If the laser beam passes through a gas plume emanating from a pipeline leak, the received energy will be diminished due to the absorption of laser light in the plume. This absorption signature is used to locate the leak and to assess its magnitude.

The equipment

The ALPIS™ system is comprised of an airborne sensor unit and operator’s console. The sensor can be mounted to any Bell Jet Ranger helicopter using a modified winch mount. Weighing in at 250 lbs, the payload is light enough to allow the crew and one passenger on-board during a typical mission. The main sensor enclosure houses the laser, computer, receiver optics and detectors. In addition, the system is equipped with a high resolution imaging camera and a GPS receiver. The combination of laser, imaging and GPS data makes it possible to precisely locate the leak. An operator, present on every flight, controls the system using a standard laptop interface and verifies the integrity of the data. We also welcome pipeline representatives to ride in the front seat of the helicopter to observe the right of way conditions.

Our new camera

LASEN has purchased two new camera systems that will provide high resolution pictures of the right of way which are tied to the GPS location of each picture. These pictures will become part of LASEN’s standard inspection service that is provided to our clients. Initially, only 300 feet or so from the centerline of the right of way will be captured in the pictures, but by the fall of 2010 we anticipate to have new technology to provide pictures covering more than 660 feet on both sides of the centerline of the right of way. These pictures will allow our customers to document the status of the right of way, the above ground facilities, potential encroachments, and the critical terrain features such as water crossings and wetlands. LASEN customers will receive both the standard inspection data plus the new pictures to advance their pipeline safety/integrity programs.