english Microbubble Formation in DAF
Pressurized Dissolved Air Flotation Process
Air Dissolution Under Pressure
In a dedicated air dissolving tank, air is injected into the water stream under elevated pressure. This pressure significantly increases air solubility in water, creating a supersaturated air-water mixture. Thorough mixing ensures air molecules fully integrate into the water rather than remaining as large, undissolved bubbles.
Rapid Pressure Release
The dissolved air water is pumped through a specialized releaser device that rapidly reduces pressure. As pressure drops sharply, the water can no longer hold the high concentration of dissolved air, leading to supersaturation. Excess gas molecules aggregate to form small gas nuclei—the initial building blocks of microbubbles.
Bubble Refinement
The releaser's internal structure, including narrow channels or porous components, creates gentle turbulence as the dissolved air water flows through. This turbulence prevents small gas nuclei from coalescing into larger bubbles and instead breaks them into uniform microbubbles.
Pollutant Separation
The resulting stream of tiny microbubbles rises slowly through the wastewater in the DAF tank. Their small size and even distribution provide ample surface area to attach to pollutants, lifting them to the surface for efficient removal.
Key Process Characteristics
- Controlled air dissolution under elevated pressure
- Sudden pressure release triggers gas nucleation
- Releaser design ensures uniform bubble distribution
- Microbubbles provide maximum surface area for pollutant attachment
- Slow bubble rise allows effective flotation and separation
