Of the earth’s surface, more than seventy per cent is water. But only three per cent of it is freshwater. But most of this freshwater is too deep in the ground or the form of glaciers or icebergs. And hence, unavailable. The remaining freshwater has a high chance of getting contaminated through chemical waste, pesticides, petroleum, sewage discharge, etc. It is necessary to purify the water and get rid of pollutants to use it. And the best way to do that is through water treatment processes.
Treating and purifying water will improve its quality and make it fit for consumption. Aside from drinking, purified clean water is also essential for agricultural and irrigation purposes. So, how does this process work? What are its stages, and why is it important? Read on!
There are four primary stages in water purification and treatment. They are as follows:
- Coagulation and Flocculation
After the water is pre-treated to remove large impurities, the first step is coagulation and flocculation. In this, coagulant aids like polymers are added to the water to make tiny particles of dirt stick together. These particles band together to form bigger particles called flocs.
- Sedimentation
After the water passes through the first stage, it moves into sedimentation tanks. The flocs formed in the previous coagulation stage settle at the bottom of the tank due to their weight.
- Filtration
After sedimentation, the next step is filtration. In this step, the water passes through various layers of filters made of many things. These layers are composed of different materials in different sizes to help filter fine dust and bacteria in the water.
- Disinfection
Once the water is filtered and purified, the last stage is disinfection. Here, a disinfectant like chlorine is added to the water to rid any remaining bacteria or parasites. This disinfected water is then ready for use.
While this is the basic process involved in water purification, some treatment processes require additional steps. There are different treatment plants like sewage treatment plants, wastewater treatment plants, stormwater treatment plants, etc. Though all these plants aim to improve water quality and provide clean water, not all of them employ the same steps all the time.
Why Is Water Treatment and Purification Important?
- Contaminated water leads to many health problems and diseases like typhoid, cholera, E.Coli. Many of these water-borne infections are dangerous and, in some cases, fatal. So it is essential to consume and use clean water for a healthy life. Treating and purifying water gets rid of harmful bacteria and viruses and decontaminates water. Thus, water purification plays a crucial role in maintaining a healthy lifestyle.
- These plants help in recycling wastewater for other purposes. Through this method, water that usually goes to waste finds new use. It helps to combat the acute water shortage problem faced everywhere in the world.
- It helps to maintain groundwater levels. Reusing and repurposing water ensures that water is not wasted and goes back into the ground. Thus making sure the groundwater level does not reduce.
- Purified water has many uses. Treated clean water is fit for drinking, irrigation, agriculture and industries for many purposes.
- With increasing water pollution, the demand for clean water rises every day. This purification of contaminated water and making it clean for consumption aids in meeting the increasing water demand.
