(173ak) Bacterial Conversion of Methane to Lipids: A Technical Assessment and Benefit-to-Cost Analysis As Methane Abatement Strategy

The reduction in greenhouse gas emissions (GHG) has become the collective goal of various countries to address the rising global climate change concerns. The United States Environmental Protection Agency proposed a new Clean Air Act rule that would lead to significant, cost-effective reductions in methane emissions in support to the Global Methane Pledge for climate change mitigation. Methane is the major component of natural gas. Natural gas is flared into the atmosphere because of its historic low and volatile prices in the past decade, which represents product and energy losses as well as major GHG emissions. One potential solution is to utilize methanotrophs due to their ability to consume methane as their sole carbon and energy source to produce a wide variety of bio-products like lipids. These bacteria are naturally present in a variety of environment such as wetlands, paddies, sediments, landfills, and waste treatment facilities. The lipids derived from methanotrophs are vital precursors for the production of green fuels and as oleochemical feedstocks. Thus, this research aimed to establish the growth conditions of methanotrophic consortium present in wastewater sludge that optimize methane consumption and lipid production. Growth parameters were varied to study the effects of media type, initial pH and methaneto air volume ratio on the bacterial conversion of methane to lipids. Moreover, this study intended to present a science-based evaluation of the benefits and costs of methane utilization for lipid production via social cost benefit analysis. The results highlight the potential of natural microbial consortium to convert methaneinto lipids using wastewater as medium that could address concerns on GHG emissions as well as for value-added resources recovery. Additionally, these findings could serve as basis for policy recommendations on the potential of methanotrophs as a methane abatement strategy toward climate change mitigation.