Here is a short overview of three modern water purification processes by Blue Fish Water, which shed light on the challenges faced by water companies today.
Reverse osmosis involves forcing large amounts of water through a semi-permeable membrane. This method requires a lot of energy, but it eliminates contaminants, chemicals, salt, and anything else that is not water.
The desalination purification process involves the use of chemicals to remove salt, contaminants, and particles from the water. Desalination has also been adapted for agricultural use. Although desalination plants are seen as essential, their release of brine into the oceans has caused serious ecological concerns.
Large scale solar distillation operations rely on sunlight and a transparent membrane to make water. Seawater and contaminated water is placed at the bottom level, where it can evaporate. As it condenses, the water is collected in a reservoir and becomes safe to drink.