title: Shear-induced detachment of biofilms from hollow fiber silicone membranes.
abstract: A suite of techniques was utilized to evaluate the correlation between biofilm physiology, fluid-induced shear stress, and detachment in hollow fiber membrane aerated bioreactors. Two monoculture species biofilms were grown on silicone fibers in a hollow fiber membrane aerated bioreactors (HfMBR) to assess detachment under laminar fluid flow conditions. Both physiology (biofilm thickness and roughness) and nutrient mass transport data indicated the presence of a steady state mature biofilm after 3 weeks of development. Surface shear stress proved to be an important parameter for predicting passive detachment for the two biofilms. The average shear stress at the surface of Nitrosomonas europaea biofilms (54.5 ± 3.2 mPa) was approximately 20% higher than for Pseudomonas aeruginosa biofilms (45.8 ± 7.7 mPa), resulting in higher biomass detachment. No significant difference in shear stress was measured between immature and mature biofilms of the same species. There was a significant difference in detached biomass for immature vs. mature biofilms in both species. However, there was no difference in detachment rate between the two species.
authors.affiliation: School of Civil Engineering, Purdue University, 550 Stadium Mall Dr., West Lafayette, IN 47907, USA.
authors.forename: Z
authors.initials: Z
authors.lastname: Huang
authors.forename: E S
authors.initials: ES
authors.lastname: McLamore
authors.forename: H S
authors.initials: HS
authors.lastname: Chuang
authors.forename: W
authors.initials: W
authors.lastname: Zhang
authors.forename: S
authors.initials: S
authors.lastname: Wereley
authors.forename: J L C
authors.initials: JL
authors.lastname: Leon
authors.forename: M K
authors.initials: MK
authors.lastname: Banks
mesh_terms: D000704:Analysis of Variance; D018407:Bacterial Physiological Phenomena; D018441:Biofilms; D019149:Bioreactors / Q000382:microbiology*; D001709:Biotechnology / Q000295:instrumentation; D057446:Hydrodynamics; D008567:Membranes, Artificial; D043370:Nitrosomonas europaea / Q000502:physiology; D011550:Pseudomonas aeruginosa / Q000502:physiology; D033081:Shear Strength; D012828:Silicones / Q000737:chemistry; D013314:Stress, Mechanical
chemical_list: D008567:Membranes, Artificial; D012828:Silicones