title: Controlling autonomous underwater floating platforms using bacterial fermentation.
abstract: Biogenic gas has a wide range of energy applications from being used as a source for crude bio-oil components to direct ignition for heating. The current study describes the use of biogenic gases from Clostridium acetobutylicum for a new application-renewable ballast regeneration for autonomous underwater devices. Uninterrupted (continuous) and blocked flow (pressurization) experiments were performed to determine the overall biogas composition and total volume generated from a semirigid gelatinous matrix. For stopped flow experiments, C. acetobutylicum generated a maximum pressure of 55 psi over 48 h composed of 60 % hydrogen gas when inoculated in a 5 % agar (w/v) support with 5 % glucose (w/v) in the matrix. Typical pressures over 24 h at 318 K ranged from 10 to 33 psi. These blocked flow experiments show for the first time the use of microbial gas production as a way to repressurize gas cylinders. Continuous flow experiments successfully demonstrated how to deliver biogas to an open ballast control configuration for deployable underwater platforms. This study is a starting point for engineering and microbiology investigations of biogas which will advance the integration of biology within autonomous systems.
authors.affiliation: Chemistry Division, US Naval Research Laboratory, 4555 Overlook Ave., SW, Washington, DC 20375, USA. justin.biffinger@nrl.navy.mil
authors.forename: Justin C
authors.initials: JC
authors.lastname: Biffinger
authors.forename: Lisa A
authors.initials: LA
authors.lastname: Fitzgerald
authors.forename: Erinn C
authors.initials: EC
authors.lastname: Howard
authors.forename: Emily R
authors.initials: ER
authors.lastname: Petersen
authors.forename: Preston A
authors.initials: PA
authors.lastname: Fulmer
authors.forename: Peter K
authors.initials: PK
authors.lastname: Wu
authors.forename: Bradley R
authors.initials: BR
authors.lastname: Ringeisen
mesh_terms: D056804:Biofuels; D046969:Clostridium acetobutylicum / Q000378:metabolism*; D003470:Culture Media / Q000737:chemistry; D005285:Fermentation; D007218:Industrial Microbiology / Q000379:methods*
chemical_list: D056804:Biofuels; D003470:Culture Media