title: Algal cell disruption using microbubbles to localize ultrasonic energy.
abstract: Microbubbles were added to an algal solution with the goal of improving cell disruption efficiency and the net energy balance for algal biofuel production. Experimental results showed that disruption increases with increasing peak rarefaction ultrasound pressure over the range studied: 1.90 to 3.07 MPa. Additionally, ultrasound cell disruption increased by up to 58% by adding microbubbles, with peak disruption occurring in the range of 10(8)microbubbles/ml. The localization of energy in space and time provided by the bubbles improve efficiency: energy requirements for such a process were estimated to be one-fourth of the available heat of combustion of algal biomass and one-fifth of currently used cell disruption methods. This increase in energy efficiency could make microbubble enhanced ultrasound viable for bioenergy applications and is expected to integrate well with current cell harvesting methods based upon dissolved air flotation.
authors.affiliation: Department of Mechanical Science and Engineering, University of Illinois at Urbana-Champaign, United States.
authors.forename: Joel D
authors.initials: JD
authors.lastname: Krehbiel
authors.affiliation: Department of Agricultural and Biological Engineering, University of Illinois at Urbana-Champaign, United States. Electronic address: schidema@illinois.edu.
authors.forename: Lance C
authors.initials: LC
authors.lastname: Schideman
authors.affiliation: Department of Mechanical Science and Engineering, University of Illinois at Urbana-Champaign, United States.
authors.forename: Daniel A
authors.initials: DA
authors.lastname: King
authors.affiliation: Department of Mechanical Science and Engineering, University of Illinois at Urbana-Champaign, United States; Department of Aerospace Engineering, University of Illinois at Urbana-Champaign, United States.
authors.forename: Jonathan B
authors.initials: JB
authors.lastname: Freund
mesh_terms: D002462:Cell Membrane / Q000648:ultrastructure; D016825:Chlamydomonas reinhardtii / Q000166:cytology*; D045423:Microbubbles; D013010:Sonication
keywords: Algal biofuel; Dissolved air flotation; Microbubble; Specific cell disruption energy; Ultrasound