Black
Carbon Emissions from Associated Natural Gas
Flaring
Cheryl L. Weyant
Paul B. Shepson
R. Subramanian
Maria
O. L. Cambaliza
Alexie Heimburger
David McCabe
Ellen Baum
Brian H. Stirm
Tami C. Bond
10.1021/acs.est.5b04712.s001
https://acs.figshare.com/articles/journal_contribution/Black_Carbon_Emissions_from_Associated_Natural_Gas_Flaring/2076820
Approximately
150 billion cubic meters (BCM) of natural gas is
flared and vented in the world annually, emitting greenhouse gases
and other pollutants with no energy benefit. About 7 BCM per year
is flared in the United States, and half is from North Dakota alone.
There are few emission measurements from associated gas flares and
limited black carbon (BC) emission factors have been previously reported
from the field. Emission plumes from 26 individual flares in the Bakken
formation in North Dakota were sampled. Methane, carbon dioxide, and
BC were measured simultaneously, allowing the calculation of BC mass
emission factors using the carbon balance method. Particle optical
absorption was measured using a three-wavelength particle soot absorption
photometer (PSAP) and BC particle number and mass concentrations were
measured with a single particle soot photometer. The BC emission factors
varied over 2 orders of magnitude, with an average and uncertainty
range of 0.14 ± 0.12 g/kg hydrocarbons in associated gas and
a median of 0.07 g/kg which represents a lower bound on these measurements.
An estimation of the BC emission factor derived from PSAP absorption
provides an upper bound at 3.1 g/kg. These results are lower than
previous estimations and laboratory measurements. The BC mass absorption
cross section was 16 ± 12 m<sup>2</sup>/g BC at 530 nm. The average
absorption Ångström exponent was 1.2 ± 0.8, suggesting
that most of the light absorbing aerosol measured was black carbon
and the contribution of light absorbing organic carbon was small.
2016-02-09 17:20:17
Associated Natural Gas FlaringApproximately 150
BC particle number
BC mass absorption
BC mass emission factors
BC emission factor
PSAP
particle soot photometer
BC emission factors
BCM
North Dakota
Black Carbon Emissions
measurement
carbon balance method