Silica Entrapment of Biofilms in Membrane Bioreactors for Water Regeneration

Abstract

The public reporting burden for this collection of information is estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data sources, gathering and maintaining the data needed, and completing and reviewing the collection of information. Habitat systems for long-term resource recovery must be reliable, safe and highly efficient, while providing potable water, oxygen, and edible biomass. Water makes up a large portion of the daily mass input into habitat systems. Considerations for water recycling technologies include shelf life, resupply-return logistics, maintenance time, power requirements, and footprint. Water recovery via physicochemical processes is limited by resupply, which can be alleviated by incorporation of an autonomous bioregenerative core, utilizing innate metabolic activity of The resultant thin silica membrane is evenly distributed over the biofilm surface, reducing molecular diffusion limitations, and reinforcing the matrix. Both P. aeruginosa (a persistent chemoheterotroph) and N. europaea (a sensitive nitrogen cycling organism) survived the encapsulation process, and retained viability and physiology over an extended period of time (at least 30 days). The silica layer reduces the detachment of cells and polymers (improving biomass conversion rate), but does not constrict active detachment of cells (required for proper physiological biofilm self-maintenance). Planktonic cells are capable of forming a secondary layer of cells/polymers on silica-encapsulated biofilms, demonstrating. The technique herein is scalable and capable of encapsulating complex geometries of immobilized bacteria by employing endogenous extracellular material as a site for silica deposition. These features will allow rapid deployment of bioreactors, which contain mature communities of microbes immobilized in biofilms, and will have the additional benefit of reducing uncontrolled biofilm erosion. Future and ongoing research will explore long term cellular viability, translation of the encapsulation system to new classes of cells, and "layering" of multispecies microbial communities in bioreactors for rapidly deployable processors for use in water reclamation systems. Silica Entrapment of Biofilms in Membrane Bioreactors for Water Regeneration AbstractHabitat systems for long-term resource recovery must be reliable, safe and highly efficient, while providing potable water, oxygen, and edible biomass. Water makes up a large portion of the daily mass input into habitat systems. Considerations for water recycling technologies include shelf life, resupply-return logistics, maintenance time, power requirements, and footprint. Water recovery via physicochemical processes is limited by resupply, which can be alleviated by incorporation of an autonomous bioregenerative core, utilizing innate metabolic activity of cells to recover useable water from various wastestreams. Major components of bioregenerative core systems include plant/crop production systems and microbial bioreactors....