title: Improving microalgal growth with small bubbles in a raceway pond with swing gas aerators.
abstract: A novel swing gas aerator was developed to generate small bubbles for improving the mass transfer coefficient and microalgal growth rate in a raceway pond. A high-speed photography system (HSP) was used to measure the bubble diameter and generation time, and online precise dissolved oxygen probes and pH probes were used to measure the mass transfer coefficient and mixing time. Bubble generation time and diameter decreased by 21% and 9%, respectively, when rubber gas aerators were swung in the microalgae solution. When water pump power and gas aeration rate increased in a raceway pond with swing gas aerators and oscillating baffles (SGAOB), bubble generation time and diameter decreased but solution velocity and mass transfer coefficient increased. The mass transfer coefficient increased by 25% and the solution velocity increased by 11% when SGAOB was used, and the microalgal biomass yield increased by 18%.
authors.affiliation: State Key Laboratory of Clean Energy Utilization, Zhejiang University, Hangzhou 310027, China.
authors.forename: Zongbo
authors.initials: Z
authors.lastname: Yang
authors.affiliation: State Key Laboratory of Clean Energy Utilization, Zhejiang University, Hangzhou 310027, China. Electronic address: juncheng@zju.edu.cn.
authors.forename: Jun
authors.initials: J
authors.lastname: Cheng
authors.affiliation: State Key Laboratory of Clean Energy Utilization, Zhejiang University, Hangzhou 310027, China.
authors.forename: Jianzhong
authors.initials: J
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Clean Energy Utilization, Zhejiang University, Hangzhou 310027, China.
authors.forename: Junhu
authors.initials: J
authors.lastname: Zhou
authors.affiliation: State Key Laboratory of Clean Energy Utilization, Zhejiang University, Hangzhou 310027, China.
authors.forename: Kefa
authors.initials: K
authors.lastname: Cen
mesh_terms: D018533:Biomass; D005740:Gases; D058086:Microalgae / Q000254:growth & development*; D010100:Oxygen; D061005:Ponds / Q000382:microbiology*
chemical_list: D005740:Gases; D010100:Oxygen
keywords: Microalgae; Raceway pond; Swing gas aerator; Water pump