title: Methane Emissions from Leak and Loss Audits of Natural Gas Compressor Stations and Storage Facilities.
abstract: As part of the Environmental Defense Fund's Barnett Coordinated Campaign, researchers completed leak and loss audits for methane emissions at three natural gas compressor stations and two natural gas storage facilities. Researchers employed microdilution high-volume sampling systems in conjunction with in situ methane analyzers, bag samples, and Fourier transform infrared analyzers for emissions rate quantification. All sites had a combined total methane emissions rate of 94.2 kg/h, yet only 12% of the emissions total resulted from leaks. Methane slip from exhausts represented 44% of the total emissions. Remaining methane emissions were attributed to losses from pneumatic actuators and controls, engine crankcases, compressor packing vents, wet seal vents, and slop tanks. Measured values were compared with those reported in literature. Exhaust methane emissions were lower than emissions factor estimates for engine exhausts, but when combined with crankcase emissions, measured values were 11.4% lower than predicted by AP-42 as applicable to emissions factors for four-stroke, lean-burn engines. Average measured wet seal emissions were 3.5 times higher than GRI values but 14 times lower than those reported by Allen et al. Reciprocating compressor packing vent emissions were 39 times higher than values reported by GRI, but about half of values reported by Allen et al. Though the data set was small, researchers have suggested a method to estimate site-wide emissions factors for those powered by four-stroke, lean-burn engines based on fuel consumption and site throughput.
authors.affiliation: Mechanical and Aerospace Engineering Department, Center for Alternative Fuels, Engines, and Emissions, West Virginia University, 151 B Engineering Sciences Building, Morgantown, West Virginia 26506, United States.
authors.forename: Derek R
authors.initials: DR
authors.lastname: Johnson
authors.affiliation: Mechanical and Aerospace Engineering Department, Center for Alternative Fuels, Engines, and Emissions, West Virginia University, 151 B Engineering Sciences Building, Morgantown, West Virginia 26506, United States.
authors.forename: April N
authors.initials: AN
authors.lastname: Covington
authors.affiliation: Mechanical and Aerospace Engineering Department, Center for Alternative Fuels, Engines, and Emissions, West Virginia University, 151 B Engineering Sciences Building, Morgantown, West Virginia 26506, United States.
authors.forename: Nigel N
authors.initials: NN
authors.lastname: Clark
mesh_terms: D000393:Air Pollutants / Q000032:analysis*; D008697:Methane / Q000032:analysis*; D059206:Natural Gas / Q000032:analysis*; D014481:United States; D001335:Vehicle Emissions
chemical_list: D000393:Air Pollutants; D059206:Natural Gas; D001335:Vehicle Emissions; D008697:Methane