In a municipal water purification plant, raw river water undergoes several sequential treatment processes to make it safe for public consumption. What is the correct chronological sequence of these major water treatment stages, from raw water intake to final distribution?
- 1Coagulation and flocculation by adding alum to aggregate fine suspended particles
- 2Sedimentation in settling basins to allow heavy flocs to sink to the bottom
- 3Filtration through sand and gravel beds to trap remaining fine solid particles
- 4Disinfection by adding chlorine gas or liquid bleach to destroy pathogenic bacteria
Answer
The correct sequence of municipal water treatment is: Coagulation/flocculation → Sedimentation → Filtration → Disinfection.
The correct sequence follows the logical progression of municipal water purification: Coagulation chemically aggregates fine particles into flocs; Sedimentation allows these heavy flocs to settle to the bottom; Filtration passes the clarified liquid through sand/gravel to catch residual solids; Disinfection is performed last with chlorine to destroy pathogenic microorganisms in clear water.
Step-by-Step Solution
Key Concept
Stages of Municipal Water Treatment