Development of microbubble aerator for waste water treatment using aerobic activated sludge

Koichi Terasaka, Ai Hirabayashi, Takanori Nishino, Satoko Fujioka, Daisuke Kobayashi

Research output: Contribution to journalArticlepeer-review

126 Citations (Scopus)

Abstract

In large-scale waste water treatment plants, the aerobic biochemical reactor is the most important process, where the oxygen supply into the microorganisms often limits the overall waste water treatment rate. On the other hand, several kinds of microbubble distributors have been developed to enrich the oxygen dissolution in water. Therefore, the application of microbubbles for a waste water treatment system was investigated in this study. The oxygen absorption performance of typical microbubble generators was compared with typical bubble generators. To evaluate each bubble generator, the liquid-phase volumetric oxygen transfer coefficient, gas hold-up and power consumption per unit liquid volume were measured in a bubble column attached to each bubble generator. All the microbubble generators allowed the oxygen to dissolve faster than the typical aerators. The spiral liquid flow type microbubble generator had the highest oxygen transfer coefficient even at a low air flow rate although it used more energy than the typical distributors. To improve an industrial waste water treatment system, a novel aeration system utilizing a spiral liquid flow type microbubble generator was proposed in this study. The present system has some advantages such as compact size, portability and fast oxygen dissolution rate. To ensure the performance for organic waste water treatment, the effects of the aeration rate, dissolved oxygen concentration and device properties on the specific consumption rate of model organic waste were investigated. For the novel aeration system, the most suitable conditions to treat organic waste were found.

Original languageEnglish
Pages (from-to)3172-3179
Number of pages8
JournalChemical Engineering Science
Volume66
Issue number14
DOIs
Publication statusPublished - 2011 Jul 15

Keywords

  • Aeration
  • Aerobic activated sludge
  • Bubble
  • Filtration
  • Multiphase flow
  • Waste water treatment

ASJC Scopus subject areas

  • Chemistry(all)
  • Chemical Engineering(all)
  • Industrial and Manufacturing Engineering

Fingerprint Dive into the research topics of 'Development of microbubble aerator for waste water treatment using aerobic activated sludge'. Together they form a unique fingerprint.

Cite this