Biomaterial Database

Demonstration of an ethane spectrometer for methane source identification. 2014

Tara I Yacovitch, and Scott C Herndon, and Joseph R Roscioli, and Cody Floerchinger, and Ryan M McGovern, and Michael Agnese, and Gabrielle Pétron, and Jonathan Kofler, and Colm Sweeney, and Anna Karion, and Stephen A Conley, and Eric A Kort, and Lars Nähle, and Marc Fischer, and Lars Hildebrandt, and Johannes Koeth, and J Barry McManus, and David D Nelson, and Mark S Zahniser, and Charles E Kolb

Aerodyne Research Inc., Billerica, Massachusetts 01821, United States.

Methane is an important greenhouse gas and tropospheric ozone precursor. Simultaneous observation of ethane with methane can help identify specific methane source types. Aerodyne Ethane-Mini spectrometers, employing recently available mid-infrared distributed feedback tunable diode lasers (DFB-TDL), provide 1 s ethane measurements with sub-ppb precision. In this work, an Ethane-Mini spectrometer has been integrated into two mobile sampling platforms, a ground vehicle and a small airplane, and used to measure ethane/methane enhancement ratios downwind of methane sources. Methane emissions with precisely known sources are shown to have ethane/methane enhancement ratios that differ greatly depending on the source type. Large differences between biogenic and thermogenic sources are observed. Variation within thermogenic sources are detected and tabulated. Methane emitters are classified by their expected ethane content. Categories include the following: biogenic (<0.2%), dry gas (1-6%), wet gas (>6%), pipeline grade natural gas (<15%), and processed natural gas liquids (>30%). Regional scale observations in the Dallas/Fort Worth area of Texas show two distinct ethane/methane enhancement ratios bridged by a transitional region. These results demonstrate the usefulness of continuous and fast ethane measurements in experimental studies of methane emissions, particularly in the oil and natural gas sector.

UI	MeSH Term	Description	Entries
D008697	Methane	The simplest saturated hydrocarbon. It is a colorless, flammable gas, slightly soluble in water. It is one of the chief constituents of natural gas and is formed in the decomposition of organic matter. (Grant & Hackh's Chemical Dictionary, 5th ed)
D003198	Computer Simulation	Computer-based representation of physical systems and phenomena such as chemical processes.	Computational Modeling,Computational Modelling,Computer Models,In silico Modeling,In silico Models,In silico Simulation,Models, Computer,Computerized Models,Computer Model,Computer Simulations,Computerized Model,In silico Model,Model, Computer,Model, Computerized,Model, In silico,Modeling, Computational,Modeling, In silico,Modelling, Computational,Simulation, Computer,Simulation, In silico,Simulations, Computer
D004980	Ethane	A two carbon alkane with the formula H3C-CH3.
D000393	Air Pollutants	Any substance in the air which could, if present in high enough concentration, harm humans, animals, vegetation or materials. Substances include GASES; PARTICULATE MATTER; and volatile ORGANIC CHEMICALS.	Air Pollutant,Air Pollutants, Environmental,Environmental Air Pollutants,Environmental Pollutants, Air,Air Environmental Pollutants,Pollutant, Air,Pollutants, Air,Pollutants, Air Environmental,Pollutants, Environmental Air
D000401	Aircraft	A weight-carrying structure for navigation of the air that is supported either by its own buoyancy or by the dynamic action of the air against its surfaces. (Webster, 1973)	Ejection Seats,Helicopters,Airplanes,Airplane,Ejection Seat,Helicopter,Seat, Ejection,Seats, Ejection
D013057	Spectrum Analysis	The measurement of the amplitude of the components of a complex waveform throughout the frequency range of the waveform. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)	Spectroscopy,Analysis, Spectrum,Spectrometry
D013781	Texas	State bounded on the north by Oklahoma, on the east by Arkansas and Louisiana, on the south by Mexico, and on the west by New Mexico.
D019015	Geologic Sediments	A mass of organic or inorganic solid fragmented material, or the solid fragment itself, that comes from the weathering of rock and is carried by, suspended in, or dropped by air, water, or ice. It refers also to a mass that is accumulated by any other natural agent and that forms in layers on the earth's surface, such as sand, gravel, silt, mud, fill, or loess. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed, p1689)	Marine Oil Snow,Sediments, Geologic,Sediments, Marine,Geologic Sediment,Marine Snow,Sediment, Geologic,Marine Oil Snows,Marine Sediment,Marine Sediments,Oil Snow, Marine,Sediment, Marine,Snow, Marine Oil