Water Treatment Process

We get water from lakes and streams and wells (aquifers) and other water sources from nature.However, nature is full of dirt, rocks, sticks, bacteria and lots of other gross stuff that we don't want to drink. So to make water potable (drinkable) we use a Water Treatment process.

Step 1 – remove obvious large objectsWhen we take water from the

source we put it through a large screen that blocks large objects such as sticks, rocks, boots, leaves, fish, etc.

Step 2 – adding chemicalsWe actually add chemicals to

make it easier to get rid of stuff other than H20. We add a chemical called alum that is stirred into the water that attracts solid waste (such as dirt that has gotten through step 1. The alum and solid waste mixture is called floc.

Step 3 – get the floc outThe water and floc mixture gets

put in a settling tank where the floc sinks to the bottom of the tank.

Flocculation, in the field of chemistry, is a process wherein colloids come out of suspension in the form of floc or flake; either spontaneously or due to the addition of a clarifying agent.

Step 4 – sand and charcoal filterThe mostly cleaned water passes

through a sand and charcoal filter. This gets rid of the last remaining solid waste that wasn't turned into floc.

Step 5 – bacteria killingBacteria may still be in the water,

so we add chlorine or ozone to attack the bacteria and kill it.

Step 6 - storageThe bacteria and floc free water

is now stored in a reservoir to be called upon when we turn on the tap.

Video to check outhttps://www.youtube.com/watch?

v=9z14l51ISwg

Other treatment methods

Reverse osmosis: a membrane with holes so small

that only water particles is placed next to water. Pressure is applied to the water to push it through the membrane where only the water gets through and everything else is left behind. Thus leaving behind only H20

Other treatment methods

Ultraviolet (UV) radiation: Fire UV rays into the water. As we

know UV rays are harmful to humans and can hurt humans, they also kill bacteria. Since UV is just light, once we turn off the source it no longer is there, thus this method will kill the bacteria and leave no harmful after effects.

Other treatment methods

Water Softening: In nature, water can absorb

calcium and magnesium from surrounding rocks. This is called 'Hard' water. It is safe to drink, but it can be damaging to pipes. We add softening chemicals (such as limewater) to remove those hard substances

Other treatment methods

Boiling water:If you have ever seen survivor or

been camping, boiling water can be used to kill most organisms. The water should be used within a few hours of boiling so that it will remain organism free.

Even with modern science, it is impossible to get certain chemicals out of our water. Chemicals such as pharmaceuticals and oils are very hard to remove, so it is of utmost importance that we keep them out of our drinking water.

Only a small portion of the water on earth is suitable for us to use. This is why we need to make sure we are not destroying the resources that we get water from. The process of ensuring we don't destroy things we will need in the future is called sustainability.

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