Aerosol pollution from gas flaring emissions in the Niger Delta region of West Africa

[摘要] Gas flaring, the disposal of gas through stacks in an open-air flame, is a common feature in the processing of crude oil, especially in oil-rich regions of the world. The rates of emission of pollutants from gas flaring depend on a number of factors including, but not limited to, fuel composition and quantity, stack geometry, flame/combustion characteristics, and prevailing meteorological conditions. In this work, new estimated emission factors (EFs) for carbon-containing pollutants (excluding PAH) are derived for a specified subset of flame condition. The air pollution dispersion model, ADMS5, is used to simulate the dispersion of pollutants from gas-flaring stacks in the Niger delta. Fuel composition and flare size play significant role in the dispersion pattern and ground-level concentrations of pollutants. To assess the significance of gas-flaring to atmospheric aerosol loading, AERONET aerosol signals are clustered using trajectory analysis to identify dominant aerosol sources at the Ilorin site (4.34o E, 8.32o N) in West Africa. From 7-day back-trajectory calculations over a 10-year period calculated using the UK Universities Global Atmospheric Modelling Programme (UGAMP) trajectory model, which is driven by analyses from the European Centre for Medium-Range Weather Forecasts (ECMWF), dominant sources are identified, using literature classifications: desert dust, biomass burning, and urban-industrial. Using a combination of synoptic trajectories and aerosol optical properties, a fourth source is distinguished: that due to gas flaring. An estimation of the relative impact of these different aerosol sources on the overall radiative forcing at the Ilorin AERONET site was the carried out.

[发布机构] University:University of Birmingham;Department:School of Geography, Earth and Environmental Sciences

[关键词] G Geography. Anthropology. Recreation;GE Environmental Sciences