Water Treatment Plant Filtration Process

Water Treatment Plant Filtration Process:

Without water, life cannot exist on earth. Due to contamination, even freshwater from rivers, lakes, streams, and underground needs filtration to make it drinkable for humans. You can remove this contamination by installing a water filtration plant. Even though the water treatment plant can be an expensive investment, it is mandatory for your health. Your liver will be thankful to you for using filtered and clean water.

Steps for the water treatment:

The water for the filtration process is drinking water from the ground, lakes, rivers, reservoirs, springs, and streams that need the filtration process to remove algae, bacteria, and protozoa. Usually, these steps are used in every filter plant with a few variations.

1 - Pre-treatment process

Water treatment starts from the pre-treatment process in which water is pumped to the filtration plant. The next step is the screening of the water. If the water is taken from pools or lakes, it may contain large materials like leaves, etc. 

Screening is done in two steps. In the first screening step, the water treatment plant excretes large materials like leaves, etc. The small matter like algae and protozoa is separated in the second screening step.

2 - Aeration:

Aeration is the third step in which water is aerated to increase the amount of oxygen in the water. Aeration helps to improve the taste of water.

3 - Coagulation

The next step is coagulation. Aluminium Sulfate and ferric chloride are added as a coagulant which helps to neutralize the negative electric charges of the fine suspended particles in the water. This process is done in a large tank where high-speed impellers mix the coagulants with water. The neutralization resulted in the formation of soft flocks.

4 - Flocculation:

After the coagulation, water is paddled. As a result, the flocks start combining and forming bigger particles. Polyelectrolytes can be used as flocculants to enhance the process.

5 - Sedimentation

The sedimentation process is used to remove these large flocculants. Water stays in a large tank for several hours. The flocculants or large soft insoluble particles settle down with the gravitational field to the tank's floor, and the water at the top becomes clear, and then this water is separated by tubes.

6 - Disinfection

Sodium hypochlorite is used as a source of chlorine to disinfect the water. The chlorine eliminates all the bacteria and microorganisms trapped in water.


The last step is filtration. Any solid material left in the water is filtered out by passing the water through the bed of sand.