Water that goes through proper drinking water treatment systems are supposed to be very safe. However, some of these treated drinking water cal also be contaminated, causing illnesses and diseases from waterborne germs like E. coli, Giarda Intestinalis and Hepatitis A.
Drinking water sources require appropriate treatment to remove pathogens as it is subject to contamination. Public drinking water systems use a range of methods of water treatment to provide safe drinking water for their societies and communities. In the globalization era of today, the most common steps in drinking water treatment systems include:
- Flocculation & coagulation – this is the first and foremost step in the drinking water treatment system. Positively charged chemicals are added to the water. The positive charge of these chemicals neutralizes the negative charge od the dissolved particles in the water like dirt. And this brings about binding of the chemicals to form larger particles, called “floc”
- Sedimentation – during this process is when the “floc” settles to the bottom of the water supply due to its heavy weight. Sedimentation refers to the settling process where it creates sediments at the bottom.
- Filtration – the clear water on top will now pass through filters of varying composition as the “floc” has settled to the bottom. This is to remove dissolved particles like parasites, dusts, viruses and bacteria.
- Disinfection – a disinfectant such as chlorine is added to the water to kill remaining bacteria and parasites once the water has been filtered. This it to protect the water from germs and viruses when it is piped to residential and industrial areas.
Even though our government has set standards for public drinking water, many Malaysians use a home drinking water treatment unit to take extra precautions because a family member is especially sensitive or in other words, has a compromised immune system. Besides that, they also want to remove specific contaminants and to improve the taste and odour of their drinking water.
There are 2 kinds of household water treatment system which are the point of use and the point of entry drinking water treatment systems. Point of entry drinking water treatment systems are usually installed after installing the water meter. This drinking water treatment system can treat most of the water entering a residence. On the other hand, point of use systems treat water in large batches and deliver the water to a tap, like kitchen sink of bathroom sink. Here are 4 most common types of household drinking water treatment systems:
- Drinking water filtration systems – water filters are a device that removes impurities from water by means of a chemical or physical barrier or even biological processes.
- Water softeners – this is a device which does an efficient job in reducing the hardness of water. A water softener usually uses sodium (Na) or potassium (K) ions to replace magnesium (Mg) and calcium (Ca) ions that create the hardness. This is because sodium and potassium are more reactive so they can easily displace magnesium and calcium.
- Water distillation systems – water distillation is a process in which impure water is boiled and the steam is collected and condensed in a separate container, leaving all the solid contaminants behind as. This is the purest form of water; however, it does not contain any minerals at all.
- Disinfection – disinfecting water can be a chemical or physical process in which pathogens are either denatured or killed entirely. Common chemical disinfectants that are used in drinking water treatment systems are chlorine and ozone. Physical disinfectants are heat, UV light and electronic rays.