Measurement of methane gas concentration by detecting absorption at 1300 nm using a laser diode wavelength-sweep technique

Kazutoshi Noda; Masanori Takahashi; Ryoji Ohba; Seiichi Kakuma

doi:10.1117/1.1829095

1 January 2005 Measurement of methane gas concentration by detecting absorption at 1300 nm using a laser diode wavelength-sweep technique

Kazutoshi Noda, Masanori Takahashi, Ryoji Ohba, Seiichi Kakuma

Author Affiliations +

Optical Engineering, Vol. 44, Issue 1, 014301 (January 2005). https://doi.org/10.1117/1.1829095

Abstract

We develop a simple piece of equipment for measuring methane (CH₄) gas concentration based on IR absorption by sweeping the wavelength of light emitted from a laser diode (LD). The principle of IR absorption enables the selective measurement of CH₄ gas by detecting an absorption line that appears around 1300 nm in the specific absorption spectrum of CH₄. Our method is simpler and more user-friendly than existing measurement methods that involve a measurement system equipped with a cell filled with a known concentration of CH4 gas and a lock-in amplifier. The results of measurements using 220- and 660-mm measurement cells show that CH₄ gas concentration is proportional to absorbance within a concentration range of 5 to 90 vol %. It is also found that our measurement system can selectively measure only the concentration of CH₄ in city gas, which is composed of a mixture of flammable gases. Moreover, a simple technique for removing humidity using silica gel and calcium chloride reduces the influence of relative humidity. These results represent performance superior to other CH₄ measurement methods currently in use.

©(2005) Society of Photo-Optical Instrumentation Engineers (SPIE)

Citation Download Citation

Kazutoshi Noda, Masanori Takahashi, Ryoji Ohba, and Seiichi Kakuma "Measurement of methane gas concentration by detecting absorption at 1300 nm using a laser diode wavelength-sweep technique," Optical Engineering 44(1), 014301 (1 January 2005). https://doi.org/10.1117/1.1829095

Published: 1 January 2005

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available