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Updated: Jun 18, 2026
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Measuring Dissolved Methane in Aquatic Ecosystems Using An Optical Spectroscopy Gas Analyzer
Published on: July 26, 2024
[Methane optic fiber sensor network based on infrared spectrum absorption in coal mine]
Xiao-jun Wu1, Peng Wang, Zhi-bin Wang
1Key Laboratory of Instrumentation Science & Dynamic Measurement (North University of China) Ministry of Education, North University of China, Taiyuan 030051, China.
Guang Pu Xue Yu Guang Pu Fen Xi = Guang Pu
|December 3, 2009
Summary
A new multi-point optic fiber sensor network accurately detects methane gas using infrared absorption. This system offers high sensitivity and rapid response for real-time monitoring.
Area of Science:
- Optoelectronics
- Spectroscopy
- Chemical Sensing
Context:
- Methane gas detection is crucial for safety in environments like mines.
- Existing methods may lack the sensitivity or real-time capabilities required for distributed monitoring.
- Infrared absorption spectroscopy offers a selective method for gas analysis.
Purpose:
- To design and develop a multi-point optic fiber sensor network for methane detection.
- To leverage the principle of gas concentration-dependent light absorption at characteristic wavelengths.
- To achieve high sensitivity, accuracy, and real-time monitoring capabilities.
Summary:
- A sensor network utilizing distributed feedback laser diode (DFLD) and InGaAs PIN photodetectors was developed.
- Space division multiple access technology (SDMAT) multiplexed sixteen methane sensors.
- Signal processing involved filtering, amplification, PCI data acquisition, and fast Fourier transform analysis.
Impact:
- Achieved a sensitivity of 200 ppm with response times under 2 seconds.
- Demonstrated long-term accuracy, stability, and a detection period under 32 seconds.
- The system is suitable for real-time, multi-point methane measurements up to 20 km from the ground, applicable in various settings.
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