It’s a known fact that 71% of the earth’s surface is covered with water. Yet there is scarcity of drinking water in most part of the world. About one billion people around the world don’t have access to pure drinking water. Mostly water present in the oceans and glaciers (which comprise 97% of the total available water) are unfit for human consumption.
Necessity for Drinking Water Purification:
Water can be broadly classified in to two broad categories: ground water and surface water, both being contributed by rain water. Rain water while falling dissolves gases, suspended particles and other substances present in the air. Rivers, lakes and reservoirs are the main source of surface water. However, these have dust particles, microorganisms, minerals and organic chemicals dissolved in them. Ground water contains lots of dissolved minerals. Therefore, on the whole, all water is not potable or drinking form of water. Thus, water needs to treated or purified to meet certain standards before using it for consumption.
Drinking Water Purification Methods:
Drinking water purification is the removal of undesirable biological and chemical contaminants from the water, thus making the water free for human consumption.
The various methods of drinking water purification are discussed as below:
• Boiling: This is the simplest way of purifying drinking water. It frees drinking water from disease-causing micro-organisms like E.coli, Cryptosporidium, Clostridium botulinum, and other enteropathogens and fungal pathogens. However, it should be noted that though boiling is the most commonly practice techniques for water purification worldwide, it is not healthy. This is because boiling not only removes the pollutants and pathogens from the water; it also removes the air and the essential minerals from it. So, water should not be allowed to boil for more than 2-3 minutes.
• Filtration: Like boiling, filtration is also not able to segregate the essential and non-essential mineral particles. Therefore, proper filtration techniques should be employed to purify the water for proper human consumption.