Petroleum refining is one of the largest industries in the US, and is a massive contributor to the national economy. However, potential environmental concerns associated with refineries have attracted government attention over the years. Under the Biden administration, Greenhouse Gas Emissions (GHGs) have come under fire, drawing a recent $250 million investment into climate-change-reducing projects. As a result, it is critically important for refineries to identify and address their sources of GHG emissions to stay in compliance with federal regulations. In this article, we will explore the largest sources of greenhouse gases in refineries and identify innovative companies making a difference in 2023.
1. Flaring and Cold Venting
One of the most distinguishable features of a refinery is the bright orange flare burning high above the plant. Unsurprisingly, the most significant source of greenhouse gases in refineries is flaring and cold venting, accounting for around 60% of emissions. Flaring is the controlled burning of excess gases that cannot be processed or stored, while cold venting is the release of gases directly into the atmosphere. Flaring is the preferred method, releasing lower-impact CO2 into the atmosphere, but cold venting can happen if the pilot light of the flare is out or other unforeseen circumstances occur. While flaring and venting are sometimes necessary for process safety reasons, companies must work to mitigate such instances or risk violating environmental regulations.
2. Tank Farm Vapors
While flaring and venting are usually the result of process-related inefficiencies that generate waste gas, leaks, and fugitive emissions stemming from faulty equipment maintenance also comprise a large part of a refinery’s emissions. According to case studies by Clean Connect, vapors emitted from storage tanks due to excess pressure are around 30% of a refinery’s emissions. Tank farms are a significant source of greenhouse gases, as they emit volatile organic compounds, such as methane, which is over 25 times more potent than CO2 at trapping heat in the atmosphere. While many refineries have implemented programs to monitor and reduce leaks and fugitive emissions, these emissions remain a significant source of GHGs. Unlike general problems with multiple probable causes like flaring/venting, tank emissions can be addressed with modern solutions such as those offered by Xtreme Tank Technologies (XTT). The Freedom Tank Tool by XTT leverages clever automation, engineering design, and process safety principles to perform enhanced methane capture in crude storage tanks. Startups like Xtreme Tank Technologies offering practical and scalable solutions to these issues will be critical for refineries to tackle environmental concerns in their tank farms as the industry moves toward a greener path.
3. Generating Utilities Energy
While the sources above generate greenhouse gases through process-related causes, one of the biggest sources of a refinery’s emissions is actually unrelated to the product they produce. In fact, coming in at number three is emissions caused by fuel consumption for utilities generation. According to the US Department of Energy, Approximately 65% of petroleum refining fuel consumption is directed to heat exchangers for process unit feed preheaters and distillation reboilers. A lot of energy is required to bring these reactions and distillations to the optimal temperature for product production, and a large quantity of fossil fuels are burned to generate this energy. Combustion of these fuels inevitably releases carbon dioxide (CO2) into the atmosphere as well as other greenhouse gases such as methane (CH4) and nitrous oxide (N2O). Emissions stemming from utilities can generate up to 4.2 million tons of CO2 per year for a typical 300-barrel-a-day refinery.
Source: Unsplash
4. Transportation
Finally, the transportation of crude oil and refined products can also contribute to greenhouse gas emissions from refineries. Transportation methods such as pipelines, tankers, and trucks all release greenhouse gases during operation, particularly if the vehicles are powered by fossil fuels. While these emissions are not directly generated by the refinery itself, they are still an important consideration when assessing the overall impact of refineries on climate change. For forward-looking operations planners and engineers, emerging technologies specializing in fleet planning and route optimization can help reduce time, costs, and emissions related to product transportation. As the oil and gas industry in the US moves into an era of declining production, leveraging data and machine learning will be critical for companies to continue generating value and trimming the fat.
Companies have been emitting risky levels of GHG’s for years, putting themselves at risk of EPA crackdowns. As government agendas shift toward increased regulation, refineries have to identify and address their GHG issues or suffer the consequences. Today, we identified some of the largest sources of of GHGs in refineries: Flaring and Cold Venting, Tank Farm Vapors, Generating Utility Energy, and Transportation. Luckily, the experienced minds of the Oil and Gas industry are constantly innovating solutions. Products like Xtreme Tank Technologies’ Tank Tool help capture and contain emissions and give the industry hope for a greener future.
