Water Treatment Technology
Today, water treatment technology is gaining increasing importance in order to ensure the quality of water supplies and hence, the environment in general. The essence of water treatment technology is to purify and cleanse water of harmful pollutants, such as sediments, bacteria and other micro-organisms, so that it can be used for the many diverse uses such as drinking water, agricultural production, sanitary discharge, industry and domestic use.
The major processes involved in water treatment include mechanical filtration, chemical precipitation, reverse osmosis, ion exchange and disinfection. The choice of treatment technology depends on the type of pollutants present and the desired degree of water purification.
Mechanical filtration is one of the oldest and most common methods of water treatment. This is a physical process involving the use of a filter to remove suspended particles based on size. Common types of filters used in this process include sand or gravel filters, multimedia filters and activated carbon filters. Depending on the type of filter used and the size of the particles to be filtered, the filtration rate can be adjusted to best achieve the desired output.
Chemical precipitation involves the addition of chemical reagents to the water in order to precipitate some of the pollutants. This process is most often used for the removal of metals and dissolved organic compounds. One of the most widely used chemical precipitation methods is coagulation/flocculation, a process in which a coagulant is added to the water to form microscopic particles which bind together to form bigger particles known as “flocs”. These flocs are then removed from the water either by settling or flotation.
Reverse osmosis is a process in which water is passed through a membrane in order to remove dissolved minerals and other impurities. This process is often used to removemicroorganisms and organic compounds as well as inorganic compounds such as nitrates and fluorides. Reverse osmosis can also be used to reduce the amount of salt in water and to reduce the level of hardness.
Ion exchange is a process in which dissolved ions and other materials are exchanged with ions of a different charge. This is best achieved by passing the water through an ion exchange resin. Common applications of ion exchange include removal of hardness or heavy metals.
Disinfection measures are often added to water treatment systems in order to further reduce the risk of contamination by microorganisms and other pathogens. Common disinfection methods include the use of chlorine, ultraviolet light and ozone. Depending on the level of contamination, different disinfection methods may be used.
By significantly reducing the concentrations of harmful pollutants, water treatment technology allows for the safe and effective reuse of water, improving human health and promoting the protection and conservation of the natural environment. As water resources are becoming increasingly scarce and water pollution is becoming a growing problem, the importance of water treatment processes is becoming increasingly evident. The investment in water treatment technology is essential to ensuring the availability of clean safe water and to protect public health.
