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Additional Treatments. 1. alum, polyacrylamide, & sand. Used at the water treatment plant to remove particles that are suspended in the water. These substances act like flypaper, trapping & dragging down suspended particles. 2. salts of iron.
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Additional Treatments 1. alum, polyacrylamide, & sand Used at the water treatment plant to remove particles that are suspended in the water. These substances act like flypaper, trapping & dragging down suspended particles.
2. salts of iron Used at the sewage treatment plant to remove phosphates: Fe 3+(aq)+ PO4 3-(aq) FePO4(s) a precipitate that be removed by filtration Phosphates can cause an algae bloom(an explosive growth ofalgae) in Lake Ontario:
3. Anthracite (Coal) & Sand Filter Media Used at the water treatment plant to remove chemicals which cause offensive odours & colours.
4. reverse osmosis Used in Saudi Arabia to produce drinking water.
6. fluoridation Fluoride is added to the water before it leaves the water treatment plant. Fluoride makes teeth more resistant to attack by acids.
fluoride damage Extremely rare . . . can only develop when a child under theageof sixreceives too much fluoride while the teeth are forming (e.g.- swallowing toothpaste) or where there is a very highconcentration of naturally occurring fluoride in the local water supply. .