There are several water treatment methods, each of which is based on a particular technique. Some of the common water purification methods are sedimentation or settling, boiling, chemical disinfection and filtration. In addition, there are other water treatment types, which are discussed as follows:

     Ultraviolet Water Treatment

     In the ultraviolet treatment, the water to be treated is passed through germicidal ultraviolet (UV) light configured inside a low pressure lamp. As the water passes the ultraviolet purifier, the biological contaminants are exposed to UV light, which damages the genetic components of the microbes. This way, the microbes are killed by using ultraviolet water treatment. A major drawback of this water treatment type is that it is ineffective in removal of dissolved chemicals and other particulate matter.

     Ozone Water Treatment

     Ozone, a colorless and unstable gas, is effective for killing the biological contaminants than that of chemical disinfection method like chlorination. Other than this, it also reduces odor problems and concentrations of iron, sulfur, manganese and other dissolved chemicals. In this water treatment type, an ozonation system is used that generates ozone gas, which is then dissolved in the raw water for treatment. The disadvantages of ozone water treatment are mild carcinogenic by-products and high cost of operation.

     Membrane Water Treatment

     Membrane technology is one of the innovative types of water treatment. Over here, a semipermeable membrane is used for the removal of water impurities. There are two types of membrane water treatment, namely, pressure-driven (e.g. reverse osmosis) and electrically driven. In the former case, hydraulic pressure is used to drive the raw water across the membrane; whereas in the latter case, electric current is used that allows the movement of water through the membrane. Though membrane water treatment removes organic and biological contaminants, it is costly to maintain.

     Reverse Osmosis Water Treatment

     Reverse osmosis (RO) is one of the most effective types of water treatment. It is usually used for home water treatment in order to remove chemical toxins, organic contaminants, pesticides and microbes. In reverse osmosis, the raw water is forced (with pressure) through a dense membrane filter that prevents passing of impurities.

     The advantages of reverse osmosis are no alteration in the taste and smell of water and effective removal of microbes and toxins. However, a major disadvantage of this treatment type is that the purified water obtained after reverse osmosis treatment is devoid of useful minerals. Membrane may become clogged after prolonged use, hence requires periodical replacement of membrane.

     It is to be noted that not all the above methods of water treatment are practiced for drinking water purification. The effectiveness of the treatment type depends on the types of contaminants and/or water quality. For the effective removal of contaminants or pollutants, a combination of treatment types can be followed at a time.

     Get more information here.