Presented By :-
Ajay Kumar Baghel
Roll no. 03
Batch – 2017-18
SWASTHVRITTA
Guided By :-
Dr. Upasna Bhardwaj (HOD)
Dr. Pavan Sharma
Dr. Rachna Agarwal
Water purification is the transition of dirty harmful (Contaminated) water into clean safe water.
Water purification generally means freeing water from any kind of impurity it contains, such as contaminants or micro organisms.
Water is of major importance to all living things.
We purify water to get rid of contaminants that can be detrimental to our health.
Up to 60 percent of the human body is Water.
Therefore the quality of Water we drink is very important.
The Drinking Water should be totally clean, pure and free of any disease causing MICROBES, and that’s why it should be properly Treated and DISINFECTED before using it for drinking purpose.
When sources of water are Rivers, Streams, Lakes etc. then water is Purified by -
When sources of water are wells, Springs, Tanks etc. Then water is purified by the addition of
Bleaching powder/Chlorinated Lime as it is
1. Boiling - for efficient boiling, the water should be ‘rolling boil’ for 5-10 minutes. It kills almost all organisms & removes temporary Hardness. The taste of water is altered, but this is harmless.
2. Filtration - Ceremic filters are used for filtration. Fine filter removes the bacteria but not the viruses. Only clean water should used in these filters, otherwise they liable to be logged with impurities.
3. ADDITION OF CHEMICALS
Bleaching Powder - 5% solution is used Dose: 3-6 drops/L contact time of ½ hour. Chlorine Tablets/Halazone Tablets one tablet/litre.
Iodine Solution - 02 drops of 2% Soln./litre
KMnO4 - an amount that gives just pink coloration to the Water.
Alum - used for turbid water in a dose of 0.1-0.4 grains/5 litres of Water.
Where does the water come from?
Water Treatment
COAGULATION:
WATER TOWARDS
SEDIMENTATION
Coagulation removes dirt and other particles suspended in water. alum and other chemicals are added to water to form tiny sticky particles called “floc” which attract the dirt particles. The combined weight of the dirt and the alums (floc) becomes heavy enough to sink to the bottom during sedimentation.
Water Treatment
WATER
FROM COAGULATION
WATER TOWARDS FILTRATION
Coagulated particles fall, by gravity, through water in a settling tank and accumulate at the bottom of the tank, clearing the water of much of the solid debris and clear water moves to filtration.
SEDIMENTATION:
Water Treatment
FILTRATION, DISINFECTION & STORAGE:
FILTRATION: The water passes through filters, some made of layers of sand, and charcoal that help remove smaller particles.
DISINFECTION: A small amount of chlorine is added or some other disinfection method is used to kill microorganisms that may be in the water.
STORAGE: Water is placed in a closed tank or reservoir for disinfection to take pace. The water then flows through pipes to home and business in the community
WATER
FROM SEDIMENTATION
Water Disinfection
To make Drinking water free of any disease causing bacteria and microbes.
There are 3 mainly used disinfection methods at large scale.
CHLORINATION OZONATION ULTRAVIOLET RADIATION
CHLORINATION
Chlorine is the most common cost-effective means of disinfecting water in the U.S.
The addition of a small amount of chlorine is highly effective against most bacteria, viruses, and protozoa.
But cysts (durable seed-like stages) formed by parasitic protozoa such as Cryptosporidium and Giardia can survive chlorine.
Chlorine is applied to water in one of three forms: elemental chlorine (chlorine gas), hypochlorite solution (bleach), or dry calcium hypochlorite. All three forms produce free chlorine in water
OZONATION
OZONE is Strongest oxidant/disinfectant available.
More effective against microbes than chlorination.
But, costly and difficult to monitor and control under different condition.
Ozonation process:
Ozone (o3) is generated on-site at water treatment facilities by passing dry oxygen or air through a system of high voltage electrodes.
ULTRAVIOLET RADIATION
When UV radiation penetrates the cell wall of an organism, it damages genetic material, and prevents the cell from reproducing.
Now a days emerging technology made UV radiation to find a place in both household and large scale drinking water disinfection.
How is UV light generated?
Ultraviolet light is most typically generated from a low pressure or a medium pressure lamp generating UV light.
ULTRAVIOLET RADIATION
COMPLETE CYCLE
OF WATER TREATMENT:
COAGULATION
SEDIMENTATION
FILTRATION
DISINFECTION
STORAGE
THANK YOU!