Methane emissions from oil and gas transport facilities – exploring innovative ways to mitigate environmental consequences

Abstract

Climate change impacts are increasingly becoming more evident e.g. through heavy rainfall episodes and subsequent flooding. Methane is a significant greenhouse gas that has been linked to these impacts and the oil and gas industry is a major source of anthropogenic methane emission. Recent studies have suggested that the tropical region hold some unexpectedly high methane concentration and that the recent changes in the global methane burden are poorly understood. To address this research gap, we present a first effort to quantify methane emissions from one of the most vulnerable oil and gas infrastructures in Nigeria (a tropical country). A combination of the Intergovernmental Panel on Climate Change tier-1 approach and an adapted Greenhouse Gases, Regulated Emissions, and Energy Use in Transportation model was used to estimate methane emissions from the system 2C transport pipeline. We then tested the hypothesis of no significant change in methane emissions trend from the pipeline using the between group t-test inferential analysis. Key findings include: (a) a crude oil throughput of 55,143 to 1,500,500 barrels (8767 to 238,561 m3) emitted methane ranging from 0.04734 to 1.288MT (± 50 to 200%) respectively, and (b) surprisingly, methane emissions along the system 2C pipeline seem to have continued without significant change between 2005, and 2008 to 2012 despite the low crude oil throughput in 2009. This indicates the likelihood of continuous but rising methane emissions from the pipeline network over a six-year period; and only further research can ascertain if similar trend can be observed elsewhere in the tropical region. These findings are unique and contribute to the current global debate on methane emissions from the largely unmonitored tropical region. Therefore, we recommend that stakeholders should set up a study plan for the identification and continuous monitoring of methane emissions from the key oil and gas infrastructure and explore opportunities for geoengineering applications as part of climate change mitigation. Coordinated engagement in international schemes such as the Natural Gas STAR program, Climate and Clean Air Coalition, Global Methane Initiative amongst others would promote strategic and measurable methane reduction plans in Nigeria and other countries within/outside the tropical region.