Water purification is the removal of contaminants from untreated water to produce water that is pure enough for a specific purpose. Most water is disinfected for human consumption (drinking water) but water purification is also required for a variety of chemical, industrial, medical and pharmaceutical processes.
General methods are:
- Physical filtration which includes media filtration, microfiltration, nanofiltration, ultrafiltration and reverse osmosis.
- Chemical filtration which includes coagulation, flocculation, ion exchange (demineralization, water softening), disinfection and electrodeionization.
- Biological treatment