What occurs during the sedimentation step in a conventional water treatment plant?

What occurs during the sedimentation step in a conventional water treatment plant?

• A. Water is disinfected with chlorine
• B. Floc settles to the bottom by gravity
• C. Particles are dissolved through chemical reactions
• D. Filters remove solids

Answer: (B)

During sedimentation, the floc formed earlier is allowed to settle out of the water by gravity in the clarifier. The heavier particles sink to the bottom, forming sludge, while clearer water remains on top to move on to the next stage. This step relies on keeping the flow slow enough and giving enough contact time for gravity to pull the particles down, rather than relying on chemical reactions or filtration. Disinfection happens later, and filtration occurs after clarification to catch any remaining fine solids.

During sedimentation, the floc formed earlier is allowed to settle out of the water by gravity in the clarifier. The heavier particles sink to the bottom, forming sludge, while clearer water remains on top to move on to the next stage. This step relies on keeping the flow slow enough and giving enough contact time for gravity to pull the particles down, rather than relying on chemical reactions or filtration. Disinfection happens later, and filtration occurs after clarification to catch any remaining fine solids.