Flow Chart: Municipal Surface Water Purification
1. Pumping raw river water through intake screens to trap large debris
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2. Dosing chemical coagulants (alum) to bind suspended colloidal dirt
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3. Gently mixing water in flocculation basins to form heavy dirt flocs
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4. Settling heavy sediment to the tank floor in quiet settling basins
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5. Filtering clear surface water through granular sand and anthracite
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6. Disinfecting with chlorine to destroy microbes before piped supply