The goal of the project is to develop a new distributed fiber optical sensing technology that can perform multi-parameter and real-time measurements of natural gas pipeline systems including direct measurements of methane concentration across long interrogation distances (e.g., up to 100 km) with spatial resolution of 1 meter per measurement.
University of Pittsburgh (Pittsburgh, PA) and Corning, Inc. (Corning, NY)
The large-scale extraction and utilization of natural gas creates significant challenges on methane leakage. This problem is exacerbated by aging gas utility delivery systems including interstate high pressure pipelines and storage facilities. As a potent greenhouse gas, leaking methane could negatively impact US efforts to reduce carbon emissions.
The scope of this project involves development of a multi-core optical fiber for simultaneous temperature, strain and optical methane absorption measurements, development of a functional polymer coating for methane detection, and ultimately, integration and testing of a fully-functional distributed fiber optical sensing technology for real-time measurement of methane emission from natural gas pipeline systems.
Research to be performed is divided into three major tasks that shall be conducted over a three year period and is designed to achieve the research objectives in the most efficient and cost‐effective way. These include:
Distributed fiber sensing technology is generally limited to monitoring a single physical parameter, such as temperature or strain. This research will transform the technology by developing new multi-core optical fibers and functional fiber polymer coatings capable of monitoring both physical and chemical parameters across the entire fiber length with high spatial resolution. In addition, by changing polymer fiber coating compositions, the optical fiber can be designed to respond to different chemical species in gaseous or liquid phases beyond methane. This will dramatically increase adaptability of distributed fiber sensors for other applications beyond natural gas pipelines, such as monitoring of oil infrastructure, hydrogen facilities, CO2 and carbon storage, and water pollution.
The project has successfully prepared the free-standing films consisting of functional polymers with and without MOF. These functional polymers are coated on the surface of the multi-mode fibers and D-shape fibers capable of strain-based and power loss sensing. Current efforts are focused on optimization of parameters to manufacture the polymer coating film and enable methane gas sensing. To improve methane detection sensitivity, the project is developing a spectroscopic approach based on tunable-diode laser (TDL) absorption spectroscopy using wavelength modulation spectroscopy (WMS). Experiments will be carried out using both single-mode (D-shaped) fiber and multi-mode fibers.