How Does Attachment and Separation Occur in DAF Flotation Equipment

Attachment and separation are the core processes in DAF flotation equipment, playing a crucial role in effectively removing contaminants from wastewater.

DAF flotation equipment makes use of a carefully engineered three - step process to achieve attachment and separation. First, the saturation step: air is dissolved in water under high pressure, typically between 30 - 50 psi. This pressurized water, rich in dissolved air, is then rapidly introduced into the flotation tank, where the sudden pressure drop causes the dissolved air to form tiny bubbles. These bubbles, with diameters usually ranging from 20 - 100 micrometers, offer a large surface area for the subsequent attachment process.

The second step is attachment. As soon as the microbubbles are released, they interact with suspended particles in the wastewater. Particle - bubble attachment occurs through multiple mechanisms. Electrostatic attraction and surface charge play important roles; when the charges of the bubbles and particles are opposite, they attract each other. Hydrophobic substances in the wastewater have an affinity for the air bubbles, facilitating attachment.

Finally, in the separation step, the attached particle - bubble aggregates rise to the surface due to buoyancy. Once at the surface, they form a floating scum layer. This layer is skimmed off using mechanical scrapers, effectively removing contaminants from the water.

Several factors can influence the efficiency of attachment and separation. The quality of the influent wastewater, the type and dosage of coagulants and flocculants added, and the design of the flotation tank all impact the process. In paper - making wastewater treatment, for example, DAF equipment successfully separates suspended fibers and fillers from the water through this attachment and separation mechanism, achieving high - quality water recycling.

Overall, the attachment and separation processes in DAF flotation equipment represent a highly effective solution for wastewater treatment, enabling the removal of a wide range of contaminants