Sep 2007

Press Release:

Temperature Measurement for Cargo Containment of LNG Tankers using Micron Optics sm125

Given the growing demand for oil and natural gas to meet the world’s energy needs, there is nowadays renewed interest in the use of liquefied natural gas (LNG) systems. For LNG to remain in its liquid phase, the gas has to be kept at cryogenic temperatures (<160°C). And, as part of the LNG supply process, it becomes necessary to transport it using massive carrier tankers with cargo hulls operating at low temperatures and using special insulating double-wall construction. The safe and reliable storage and transportation of LNG products calls for low temperature monitoring of said containers to detect the onset of any potential leaks and possible thermal insulation degradation. Because of the hazardous nature of this cargo, only intrinsically-safe, explosion proof devices can be used. Optical fiber sensors—such as fiber Bragg gratings—are ideal for this application given their dielectric nature and multi-point sensing telemetry capability.

An online LNGC container temperature monitoring system has been developed and designed around the use of fiber Bragg grating temperature sensors. The FBG sensors have been designed using a proprietary encapsulation technique and packaged inside specially designed housings for installation in the hull, inner barriers and barriers of cryogenic LNG container tanks. All the sensors were monitored by s a Micron Optics sm125-700 optical interrogator. Data will be collected automatically by this unit and relayed to a processing computer for further analysis and display. The FBG temperature sensors were demonstrated to be stable and sensitive over the 80-480K range. Stability is ± 0.25K or better with repeated calibrations, and long term stability at 480K is ~0.2mK/hour.

About Micron Optics, Inc.

Micron Optics, a leading provider of tunable optical technologies, offers a comprehensive portfolio of components and instruments for Optical Sensing, Biotech and Telecom markets. Built upon its solid technology foundation, Micron Optics' products span from simple tunable components to fast swept laser modules to fast and accurate optical instrumentation. Since 1990, Micron Optics has been a privately held company based in Atlanta.