Methods of Water Purification

Water purification

Water is a necessary element for living organisms to survive. Consumption of impure water causes various diseases.

1. Boiling

Water needs to be boiled for 10-15 minute to make it drinkable. It is not good to heat the water to lukewarm and drink it because this does not destroy germs properly. Boiled water should be kept in a clean pot and covered.

2. Sedimentation and Decantation

If water is left still in a container for a long period of time then solid dirt settles to the bottom. This solid is known as sediments. This process of settling dirt to the bottom is called sedimentation. If water is poured out with the help of a glass rod as shown in the picture. Then we can seperate solid dirt from the clean water.

3. Chlorination of water:

Germs in the water are responsible for spreading of cholera, dysentery, typhoid and jaundice. To protect ourselves from germs and other harmful organisms we need to add a chemical called chlorine in the water. This kills all the germs and purifies the water. Pregnant women should not drink this water. If chlorine is added in large quantity, it becomes poisonous. Therefore, this purification of water needs to be done carefully.

4. SODIS method:

Solar water disinfection system also known as SODIS is a method of water purification that uses solar energy to make biologically-contaminated (e.g. bacteria, viruses, protozoa and worms) water safe to drink. If the water is contaminated with non-biological factors such as toxic chemicals or heavy metals, then it requires further steps to make the water safer.

There are three ways of SODIS:

• Electric: Solar disinfection using the effects of electricity
• Heat: solar thermal water disinfection.
• UV: Solar ultraviolet water disinfection.

Methods of filtering water

Water contaminated with solid dirt can be filtered using filter paper. Following are the methods of filtration of water.

Using water filter

Water filter could filter the water easily. This water filter has two containers. Filter candles are attached in the upper container. When water is kept in a container, water slowly gets filtered through this and drops down to the lower container. The water tap is attached to the lower container. From this tap, it is possible to open it and take the necessary amount of water for drinking.

Process of filtering water through sand and gravel:

An empty container is kept at the bottom and a second container is filled with pebbles and kept on the top of the first container. The third container filled with sand is kept on the top of the second one. At the top, a container filled with water is kept.The three containers on the top have small holes at the base through which water slowly gets filtered and stored in the bottom container. This container must be cleaned time to time. This filtration method can also be done according to the figure shown.

Appropriate uses of other water:

For the proper use of water unnecessary wastage of other water sources can also be used properly. Remaining water from the washing utensils, washing clothes, kitchen and other household works could be used for kitchen garden and gardening at home. In monsoon the rain water, which is dropped from the roof, could be collected for the use of different works.