Dissolved-air flotation is particularly good for removing:

• A. Heavy metals
• B. Suspended solids
• C. Algae
• D. Bacteria

Answer: (C)

Dissolved-air flotation (DAF) is specifically designed to remove suspended solids, including algae, from water. The process works by generating microbubbles in water, which attach to particles, including algae. This attachment causes the particles to rise to the surface, forming a scum layer that can be easily removed.

Algae can often create significant problems in water treatment processes due to their ability to reproduce quickly and their tendency to obstruct filters. DAF is particularly effective for treating water contaminated with algae because it enhances the buoyancy of these particles, facilitating their removal.

While DAF may assist in the removal of some heavy metals, bacteria, and other contaminants, its primary strength lies in its ability to efficiently separate and remove suspended solids, particularly those like algae that can significantly affect water quality.