Indonesia
Purify, then Drink It
Irwan was thirsty and need some water to drink. He went to the refrigerator and took a bottle of water. He enjoyed drinking clean and fresh water. Then, he became wondering; how can people make clean bottled water? In big city, it is hard to find spring as a source of fresh water.
Thanks to water treatment system developed by human. Using the system, people can turn water from river into drinking water or to safe water (which can be used for bathing or cleaning). But, Superkids, do you know how the water purification work?
At least, there are five basic steps for water purification. We must collect enough water to be purified into clean water for consumption. Then, the first step is coagulation. Into the water, add some coagulants (like lime and alum) which cause particulates to clump together.
The next step is shaking; the water is shaken into larger clumps. Then, sedimentation process takes place. Let the water stand for 24 hours to allow the clumps to settle to the bottom. The four steps is filtering. The water is filtered to throw away the dirt.
To make it free from bacteria or other germs, the next steps is aeration. The water is disinfected usually with chlorine to kill the germs and then aerated to remove certain contaminants such as radon. After the five processes, we may put the water into bottle.
Other way to purify water is boiling it. Heat may kill germs and kick away some dirt. However, boiling is not effective to make clear water directly from river.
TEGUH WAHYU UTOMO
PHOTOS: THINKSTOCK
