WATER TREATMENT

IT IS THE PROCESS OF REMOVING IMPURITIES OF RAW WATER TO

BRING ITS QUALITY UP TO CERTAIN REQUIRED STANDARDS IS CALLED

WATER TREATMENT.

TREATMENT METHODS1. SCREENING2. PLAIN SEDIMENTATION3. SEDIMENTATION WITH CO- AGULATION4. FILTERATION5. AERATION & CHEMICAL TREATMENT6. DIS-INFECTION

THIS IS PRIMARY STAGE OF TREATMENT USED TO REMOVE LARGEST SIZE IMPURITIES…….

TYPESOF IMPURITIES REMOVED FLOATING – BUSHES, DEAD ANIMALS,

LEAVES, BRANCHES OF TREES ETC. SUSPENDED – WOODEN PIECES, CLOTH

PIECES ETC.

SCREENING

IT IS THE PROCESS OF REMOVING THE SUSPENDED PARTICLES

IT IS OF PHYSICAL IN NATURE IT IS BASED ON SETTLING THE HAVIER

PARTICLES IT IS POSSIBLE WITH THE SLOW SPEED OF

WATER THIS PROCESS TAKES PLACE IN TANKS

CALLED SEDIMENTATION TANKS

SEDIMENTATION

PLAIN SEDIMENTATION…………AGGREGATION OF IMPURITIES

DONE WITH GRAVITATIONAL PULLS TO PARTICLES

SEDIMENTATION WITH COAGULATION…………..AGGREGATION OF IMPURITIES

DONE WITH THE HELP OF OTHER CHEMICAL OR SUBSTANCE

TYPES OF SEDIMENTATION

REDUCES THE LOAD ON NEXT PROCESSES

CLEANING COST OF COAGULATION REDUCED

IT IS SIMPLE & PHYSICAL IN NATURE

LESS QUANTITY OF CHEMICAL IS REQUIRED

ADVENTAGES OF PLAIN SEDIMENTATION

1. INTERMITTENT TANK

2. CONTINUOUS FLOW TYPE TANK

TWO TYPES OF SEDIMENTATION TANKS

THE PROCESS OF ADDING CERTAIN CHEMICALS TO RAW WATER IN ORDER TO FORM FLOC {INSOLUBLE GELATINOUS SUBSTANCE} FOR QUICK SEDIMENTATION AND REPID REMOVAL OF FINE PARTICLES IS CALLED SEDIMENTATION WITH COAGULATION

THESE CHEMICAL COMPOUNDS ADDED ARE CALLED COAGULANTS

SEDIMENTATION WITH COAGULATION

ALUMINIUM SULPHATE – Al(SO4)318H20…..IS ALSO CALLED ALUM

-----BETTER RESULT

------CHEAP IN COST

------HAS NO CHLORINE DEMAND

-------COMMONLY USED IN PLANTS

COMMAN COAGULANTS

IRON SALTS………………..FERROUS SULPHATE, FERRIC

CHLORIDE, FERRIC SULPHATE

CHLORINATED COPPERAS………MIXTURE OF FERRIC SULPHATE &

FERRIC CHLORIDESODIUM ALUMINATE

OTHER COMMAN COAGULANTS

SOLUTION FEED DEVICES

DRY FEED DEVICES

FEEDING DEVICES

FLOW TYPE

MECHANICALLY AGITATED

MIXING DEVICES

FLOCCULATOR

THE PROCESS OF PASSING THE RAW WATER

THROUGH A THICK LAYER OF SAND AND

GRAVEL WHICH ACT AS A STRAINER IS

CALLED FILTERATION

FILTERATION

1 MECHANICAL STRAINING

2 SEDIMENTATION

3 ABSORPTION

4 BIOLOGICAL ACTIVITY

5 ELECTROLYTIC ACTION

FIVE ACTIONS OF FILTERATION

SLOW SAND FILTER

RAPID GRAVITY SAND FILTER

FILTERATION

TO KILL THE BECTERIAL INFECTION

CHLORINATION

TO REMOVE DISSOLVED GASES OTHER THAN OXYGEN & NITROGEN TO GET THE WATER FREE FROM ONPLEASANT ODOUR & TASTE

……. IT IS DONE BY INJECTING FOUNTAIN OF AIR INTO THE WATER

AERATION