Water Purification
This can differ very much for different types of water.
In which ways is polluted water treated?
Settling
Before the purification process begins some contaminants, such as oil, can be settled in a settling tank. They can then be removed easily, after
they have reached the bottom of the tank.
Removal of dangerous microorganisms
Often polluted water has to be freed from microorganisms. The water is than disinfected, usually by means of chlorination.
Removal of dissolved solids
Microrganisms are not only a threat to water; they can also be an advantage when it comes to water purification processes. They can convert
harmful contaminants to harmless substances. This biological purification process usually takes a long time and it is only used for water that is
polluted with contaminants that the microrganisms, usually bacteria, can convert.
Physical/ chemical techniques
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