Mississippi State University
Rogers, E. Rudy
Minerick, R. Adrienne
Hill, J. Priscilla
French, W. Todd
Date of Degree
Graduate Thesis - Open Access
Master of Science
James Worth Bagley College of Engineering
Dave C. Swalm School of Chemical Engineering
Bacillus subtilis capable of producing surfactin was cultured to evaluate effects of microbial cell mass on natural gas hydrate formation, dissociation, and stability characteristics. The direct molecular influences of microbial cell wall polymers inhibited gas hydrate formation significantly, decreased hydrate formation rates, and increased dissociation rates. Upon the introduction of bentonite, significant synergy was observed in the system in the form of a catalytic effect. Microbes cultured from seafloor seawater-saturated sediments collected from Mississippi Canyon 118 (MC-118) produced similar effects and generalized the observed trends. MC-118 cultures also produced biosurfactant in several culture media, which was shown to catalyze natural gas hydrate formation in porous media. Microorganisms inhabit gas hydrate macrostructures and consume hydrocarbons and other substrates from within. Sulfate reduction and anaerobic hydrocarbon oxidation occurred within gas hydrate during incubations with MC-118 indigenous consortia. A mathematical model was developed to explore the diffusion-reaction implications in massive seafloor gas hydrates.
Radich, James Gregory, "Laboratory and theoretical investigations of direct and indirect microbial influences on seafloor gas hydrates" (2009). Theses and Dissertations. 2909.