Energy & Emissions Research Laboratory, Department of Mechanical and Aerospace Engineering, Carleton University , 1125 Colonel By Drive, Ottawa, Ontario K1S 5B6, Canada.
Environ Sci Technol. 2017 Feb 7;51(3):1893-1900. doi: 10.1021/acs.est.6b03690. Epub 2017 Jan 9.
Black carbon (BC) emissions from gas flaring in the oil and gas industry are postulated to have critical impacts on climate and public health, but actual emission rates remain poorly characterized. This paper presents in situ field measurements of BC emission rates and flare gas volume-specific BC yields for a diverse range of flares. Measurements were performed during a series of field campaigns in Mexico and Ecuador using the sky-LOSA optical measurement technique, in concert with comprehensive Monte Carlo-based uncertainty analyses. Parallel on-site measurements of flare gas flow rate and composition were successfully performed at a subset of locations enabling direct measurements of fuel-specific BC yields from flares under field conditions. Quantified BC emission rates from individual flares spanned more than 4 orders of magnitude (up to 53.7 g/s). In addition, emissions during one notable ∼24-h flaring event (during which the plume transmissivity dropped to zero) would have been even larger than this maximum rate, which was measured as this event was ending. This highlights the likely importance of superemitters to global emission inventories. Flare gas volume-specific BC yields were shown to be strongly correlated with flare gas heating value. A newly derived correlation fitting current field data and previous lab data suggests that, in the context of recent studies investigating transport of flare-generated BC in the Arctic and globally, impacts of flaring in the energy industry may in fact be underestimated.
燃烧天然气产生的黑碳（BC）排放被认为对气候和公共健康有重大影响，但实际排放率仍未得到充分描述。本文介绍了一系列在墨西哥和厄瓜多尔进行的实地考察中，使用天空 LOSA 光学测量技术与全面的基于蒙特卡罗的不确定性分析相结合，对各种燃烧器的 BC 排放率和燃烧器气体体积比 BC 产率进行的现场实测结果。在部分地点成功进行了燃烧器气体流速和成分的同步现场测量，从而能够在现场条件下直接测量燃烧器的燃料特异性 BC 产率。单个燃烧器的定量 BC 排放率跨越了 4 个数量级以上（高达 53.7 g/s）。此外，在一次显著的约 24 小时燃烧事件（在此期间，羽流透射率降至零）期间的排放量甚至比这一最大速率还要大，因为这一事件是在测量结束时发生的。这突出了超级排放源对全球排放清单的重要性。燃烧器气体体积比 BC 产率与燃烧器气体热值呈强相关。一个新的相关关系拟合了当前的现场数据和以前的实验室数据，表明在最近研究燃烧产生的 BC 在北极和全球的传输的背景下，能源工业中的燃烧器排放实际上可能被低估了。
