Journal
ENVIRONMENTAL ENGINEERING RESEARCH
Volume 24, Issue 3, Pages 382-388Publisher
KOREAN SOC ENVIRONMENTAL ENGINEERS
DOI: 10.4491/eer.2018.210
Keywords
Bubble size; Bubble volume concentration; Nano bubbles; Rising velocity; Sub-micron bubbles; Zeta potential
Categories
Funding
- Korea Environment Industry & Technology Institute (KEITI) through Public Technology Program based on Environmental Policy - Korea Ministry of Environment (MOE) [2018000200001]
Ask authors/readers for more resources
Although nanobubbles attract significant attention, their characteristics and applications have not been thoroughly defined. There are diverse opinions about the definition of nanobubbles and controversy regarding methods that verify their characteristics. This study defines nanobubbles as having a size less than 1 mu m. The generation of these sub-micron (nano) bubbles may be verified by induced coalescence or light scattering. The size of a sub-micron (nano) bubbles may be measured by optical, and confocal laser scanning microscopy. Also, the size may be estimated by the relationship of bubble size with the dissolved oxygen concentration. However, further research is required to accurately define the average bubble size. The zeta potential of sub-micron (nano) bubbles decreases as pH increases, and this trend is consistent for micron bubbles. When the bubble size is reduced to about 700-900 nm, they become stationary in water and lose buoyancy. This characteristic means that measuring the concentration of sub-micron (nano) bubbles by volume may be possible by irradiating them with ultrasonic waves, causing them to merge into micron bubbles. As mass transfer is a function of surface area and rising velocity, this strongly indicates that the application of sub-micron (nano) bubbles may significantly increase mass transfer rates in advanced oxidation and aeration processes.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available