Article | Types of water treatment

Water does not regenerate, it is recycled over and over again. Because of this, water often needs to be treated at a wastewater treatment plant in order to ensure it is in a safe and usable state. Wastewater treatment plants adopt a number of treatment methods to remove impurities found in the wastewater.

Households and industries create a huge amount of wastewater every day. Therefore, treatments are available for both homes and businesses at all points across the wastewater cycle.

Water treatments for businesses and homes are designed to kill bacteria and disinfect the water to make it safe for human consumption.

WATER TREATMENTS AVAILABLE AT WASTEWATER TREATMENT PLANTS

• Coagulation and flocculation – the coagulation process binds small particles together to create dense particles called floc. As the flock is relatively heavy, it settles and is then removed from the wastewater.
• Sedimentation – this is a separation process in which solids are allowed to settle at the bottom of a sedimentation chamber or tank to produce a layer of sludge – oils and grease then rise to the top to form scum. The sludge and scum are removed from the tank and the cleaner water passes through.
• Filtration – filtration is achieved by passing wastewater through screens which contain openings to let the water pass through (leaving behind any large solids present in the water).
• Disinfection – microorganisms are killed using a range of methods. For example, the addition of chemicals such as chlorine or ozone or utilizing a physical method such as ultraviolet (UV) light, radiation and heat transfer effectively kill microorganisms.

WATER TREATMENTS FOR INDUSTRIES

• Filtration – filtering water through sand or a carbon filtration unit absorbs organic contaminants, which can help with odor control and improve taste.
• Chemical treatments – all businesses should be aware of the risks of legionella and the availability of chemical treatments to kill the bacteria. Other chemical treatments include the removal of scale and other deposits from the water which bacteria feed on.
• Physical treatments – physical methods of wastewater treatment involve screens or barriers which wastewater passes through to leave behind bulky waste in the water.
• Disinfection – disinfection methods involve the addition of disinfection systems to heating and cooling systems. The system injects disinfectants such as chlorine directly into the industrial water system to prevent and kill bacteria.

WATER TREATMENTS FOR HOUSEHOLDS

• Filtration systems – filtration devices can be added to water supplies to filter out impurities and improve the taste of drinking water.
• Distillation systems – a distillation unit is used heat water to produce steam which is collected and cooled, ready for use. Distillation removes any impurities in the water.
• Disinfection – disinfectants are added to the water to kill microorganisms such as bacteria to produce clean, safe drinking water.
• Water softeners – hard water deposits and limescale provide essential nutrients for bacteria growth. Adding water softeners prevents the build-up of scale and deposits in water pipes to reduce the risk of bacterial illnesses.

NCH Asia has developed a wide range of water and wastewater treatment solutions including physical and chemical treatments. Learn more about our approach to wastewater management.