Water Treatment
Section: 10. Chemistry of the Environment | Syllabus: Cambridge AS Level Physics 9702
Water Treatment Purpose of Water Treatment Water from natural sources must be treated to make it safe for drinking and domestic use. The treatment process removes suspended solids, harmful microbes, and other contaminants.
Steps in Water Treatment Water treatment involves several key stages: 1. Sedimentation: Water is left to stand in large tanks, allowing heavy particles and suspended solids to settle to the bottom 2. Filtration: Water passes through filter beds (sand and gravel) to remove remaining fine particles and some microbes 3.
Use of carbon: Activated carbon is used to remove tastes, odors, and some dissolved organic compounds through adsorption 4. Chlorination: Chlorine gas (or chlorine compounds) is added to kill harmful bacteria and microbes, making the water safe to drink Treatment Stage What It Removes How It Works Sedimentation Large suspended particles, dirt, debris Gravity causes heavy particles to settle Filtration Fine particles, some microbes Physical barrier (sand/gravel) traps particles Carbon treatment Tastes, odors, organic compounds Activated carbon adsorbs dissolved substances Chlorination Harmful bacteria, viruses, microbes Chlorine oxidizes and kills microorganisms Importance of Each Stage Sedimentation: Reduces load on filters, removes bulk of solids Filtration: Removes particles that could harbor bacteria Carbon: Improves taste and removes chemical contaminants Chlorination: Final safeguard against disease-causing organisms
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