What is the correct sequence of the following drinking water treatment processes from initial to final? A. Filtration B. Disinfection C. Gravity settlement of large particles D. Flocculation
Choose the correct answer from the options given below:

Correct option is C

The correct sequence of drinking water treatment processes follows a logical progression to ensure water is purified effectively:
1. Gravity Settlement of Large Particles (C): This initial step removes large and heavy particles (like sand and grit) through sedimentation in settling tanks.
2. Flocculation (D): Coagulants are added to water to aggregate fine particles into larger clumps (flocs), making them easier to remove during filtration.
3. Filtration (A): The water is passed through filters (sand, gravel, or membrane filters) to remove smaller suspended particles and impurities.
4. Disinfection (B): Finally, disinfection (commonly using chlorine or ultraviolet light) eliminates any remaining pathogens, making the water safe for drinking.
Thus, the correct sequence is: C → D → A → B.
Information Booster:
1. Gravity Settlement: Essential for removing heavy particles to prevent clogging in subsequent processes.
2. Flocculation: Increases efficiency by aggregating fine particles. Coagulants like alum are often used.
3. Filtration: Removes remaining solids and impurities, enhancing water clarity.
4. Disinfection: Ensures the destruction of harmful microorganisms, making water microbiologically safe.
5. Proper sequencing ensures efficient treatment and compliance with drinking water standards.