Water Treatment Methods : Step By Step
Water is considered to be the purest drink. Structure wise it is made up of atoms of oxygen and hydrogen. The way water is supplied around the world however shares its space with different minerals, organic materials, manmade pollutants and chemicals.
This makes the water polluted and not suitable for consumption. It can have signs of bacteria, viruses, and other organisms that can cause deadly diseases.
To avoid this, water treatment methods are being used to purify water before it becomes available for consumption.
The methods that are available to purify water differ in different places as it is dependent on the technology of the plant and water that has to be made pure.
Apart from this overpopulation and the limitation of resources does not allow us to have a free hand while utilising resources and so a lot of water is also wasted daily.
This includes water running from the shower and runoff from wet roads. Reuse of water has become an integral part to creating a sustainable environment as we need to consume it efficiently.
Waste water also needs to go through a purification process before it can be fit for consumption.
The procedures are standard everywhere and listed below are a few water treatment methods:
1. Coagulation / Flocculation
This is a common physico-chemical process. This process includes adding polymer to untreated water and the mixture created by this causes the particles in the water body to stick together.
The group of particles that become attached to each other form larger particles called flocs. These particles can then be conveniently removed through filtration.
This method functions effectively over wide ranges of pH and water of any temperature.
This method produces lesser chemical and metal residuals and achieves water treatment goals.
During the process of treatment, the water is taken to basins of sedimentation. In these basins, the speed of water movement is very slow and all the heavy floc settles at the bottom.
The accumulation of the flocs at the bottom is call sludge. This is then directed to drying area or drying lagoons.
This process is recommended before the actual purification of water takes place. It can also be accelerated by adding special chemicals or coagulants.
One drawback is that not all bacteria is settled out and so the water needs to go through further purification before it is fit to be consumed.
This process removes particles from suspension in water. Water is run through a filter. This helps in getting rid of all the particles. The filters used for this are usually composed of sand, gravel or crushed anthracite.
The process of filtration is responsible for gathering all the dirty particles and impurities in water and reduces chances of infections and viruses.
Filters that are used in this process are also regularly cleaned to make sure that no impurities are left behind.
Fluoridation is done to make sure that the levels of fluoride in water are at an optimal level for consumption.
It is expensive to remove fluoride from water, however there are some water sources that have no fluoride and so it is added into the water at a level that is safe for consumption as it is inexpensive to do so.
Fluoride also promotes dental and oral health and so the governments make sure fluoridation is done.
5. pH Correction
Correction of pH is done before water is treated in the plants. The pH of water determines the solubility and availability of chemical solutes which includes metals and nutrients.
Metals are more toxic at a lower pH as they are more soluble then.
Solutions that deviate from the neutral pH value of 7, damages solids that come into contact with it. The monitoring and correction of pH is done to guarantee clean and safe water.
This can be done manually or automatically in a water stream.
These five methods are the most essential in treating waste water and purifying water for consumption.
These are done on a large scale and in water purification plants before it goes out for consumption.
The technology for these methods is always being updated to make sure the quality of the drinking water is most safe.
Many third world countries are still lacking behind and dirty water is still a large problem in these countries.
If you know any water treatment methods, please leave it in the comment.