@article{938966206eb544f7b0b066a2905dd432,
title = "Determining biogenic content of biogas by measuring stable isotopologues 12CH4, 13CH4, and CH3D with a mid-infrared direct absorption laser spectrometer",
abstract = "A tunable laser absorption spectrometer (TLAS) was developed for the simultaneous measurement of δ 13C and δD values of methane (CH₄). A mid-infrared interband cascade laser (ICL) emitting around 3.27 µm was used to measure the absorption of the three most abundant isotopologues in CH₄ with a single, mode-hop free current sweep. The instrument was validated against methane samples of fossil and biogenic origin with known isotopic composition. Three blended mixtures with varied biogenic content were prepared volumetrically, and their δ 13C and δD values were determined. Analysis demonstrated that, provided the isotopic composition of the source materials was known, the δ 13C and δD values alone were sufficient to determine the biogenic content of the blended samples to within 1.5%. ",
keywords = "Biogas, Biogenic determination, Bioprocess monitoring, Direct absorption, Laser-based sensors, Stable isotopologues",
author = "Teemu K{\"a}{\"a}ri{\"a}inen and Richmond, {Craig A.} and Albert Manninen",
note = "Funding Information: As the utilisation of renewable energy sources increases globally, the safe and efficient integration of biofuels into existing energy infrastructures becomes particularly pertinent. Biogas is one such renewable energy source, with the potential to replace fossil fuels for applications such as power production and transportation fuel. Within Europe, this transition is supported by the Renewable Energy Directive 2009/28/EC [1], which promotes the use of renewable sources and thus drives the diversification of the natural gas supply. Due to increasing European biogas production [2,3], and to support the use of green gas, the European Committee for Standardization (CEN) has worked to establish technical specifications for both biogas (a mixture of methane and other gases, such as CO2) and biomethane (purified biogas with higher methane content), with the aim of allowing safe injection to the natural gas distribution grids, and for use as a fuel for vehicle engines [4]. Funding Information: Acknowledgments: The presented work was funded by the Academy of Finland and the European Metrology Research Programme (EMRP) project ENG54 “Metrology for Biogas”. The EMRP is jointly funded by the EMRP participating countries within EURAMET and the European Union. The authors thank Gasum Oy for providing the sample gases and the Stable Isotope Laboratory at the Max-Planck Institute for Biogeochemistry, Jena, Germany, for mass-spectrometry analysis of calibration gases. Publisher Copyright: {\textcopyright} 2018 by the authors. Licensee MDPI, Basel, Switzerland. Copyright: Copyright 2018 Elsevier B.V., All rights reserved.",
year = "2018",
month = feb,
day = "7",
doi = "10.3390/s18020496",
language = "English",
volume = "18",
journal = "Sensors",
issn = "1424-8220",
publisher = "MDPI",
number = "2",
}