Chlorination of well is important in village area to prevent water borne and water washed disease .

1. COLLEGE OF NURSING
AIIMS RAIPUR
SUBJECT – COMMUNITY HEALTH NURSING
PRESENTATION ON – CHLORINATION OF
WELL
SUBMITTED TO SUBMITTED BY
Mr. Abdul munaf sir Teena goswami
CON Aiims Raipur Roll no. 296
Nursing tutor Bsc [hons] nursing 4th year

2. OBJECTIVES
At the end of the lecture student will be able to –
-Introduce about chlorination process of well
-Define chlorination of well
-Mechanism of action of chlorine on water.
-Chlorine treatment standards , chlorine demand .
-Step in well disinfection .
-The double pot method .
-Precaution should be taken when chlorinating well.

3. CHLORINATION OF WELL
Introduction – well are the main source of water
supply in the rural areas. The need often arises to disinfect
them, sometimes on a mass scale , during epidemics of
cholera and gastroenteritis . The most effective and
cheapest method of disinfecting wells by bleaching powder.

5. DEFINITION
Disinfection of wells by using chlorine gas , chlorinated lime
{caocl2} or bleaching powder.
Chlorination- is the process of adding the element
chlorine to water as a method of water purification to make
it fit for human consumption as drinking water .

6. MECHANISM OF ACTION OF CHLORINE
ON WATER
Cl2 +H2o ---------- Hocl + ocl-
Cl2 + water ------- 1. oxidizing organic acis
2. Reacts with organic nirtrogen
3. oxidize inorganic salts .
4. Free chlorine --- Hocl
----ocl

7. CHLORINE TREATMENT STANDARDS Cx T
T = Time water is in contact with the chlorine
C = concentration of free chlorine {mg /l }
Need Cx T = 6 – for ground water .
0.3 mg/l for 20 min. same as 0.6 mg/l for 10 min.

8. CHLORINE DEMAND
It is the inherent properties of the water that consume
chlorine .
Or
Chlorine demand is the difference between the amount of
chlorine added to water or waste water and the amount of
residual chlorine remaining after a given contact time ,
called chlorine demand of the water , and it may change
with time temp. pH , and nature and amount of impurities in
the water.

9. TOTAL CHLORINE –
The remaining chlorine concentration after the chlorine
demand .
- Total chlorine –1 . combined chlorine – react with nitrate
and unavailable for disinfection .
- 2. Free chlorine –chlorine available to inactivate disease
causing micro- organism and thus a measure to
determine the potability of water .
-

10. STEPS IN WELL DISINFECTION-
1. Find the volume of water in a well.
A} Measure the depth of water column--- h {m}
B} Measure the diameter of the well – d {m}
C} Substitute h and d in
volume {L} = 3.14 d²xh x 1000/4
D} one cubic meter = 1,000 litres of water .

11. 2. FIND THE AMOUNT OF BLEACHING POWDER
REQUIRED FOR DISINFECTION.
Annex- III – gives the amount of chemical needed
to disinfect water for drinking
Roughly – 2.5grams of good quality , bleaching
powder is required to disinfect 1,000 liter of water .
0.7 mg bleaching powder applied / litre of water .

12. 3. DISSOLVE BLEACHING POWDER IN WATER .
The bleaching powder required for disinfecting the well is
placed in a bucket { not more than 100mg in one bucket of
water } and made into thin paste , more water is added till
the bucket is nearly 3/4 full. The content are stirred well, and
allowed to sediment for 5 to 20 min, when lime settles down
. Supernatant solution which is chlorine solution, is
transferred to another bucket and the chalk or lime is
discarded .

13. 4. DELIVERY OF CHLORINE SOLUTION INTO THE
WELL
The bucket containing the chlorine solution is lowered some
distance below the water surface , and the well water is
agitated by moving the bucket violently both vertically and
laterally. This should be done several times so that the
chlorine solution mixes intimately with the water inside the
well.

14. 5. CONTACT PERIOD
A contact period of one hour is allowed before the
water is drawn for use.

15. 6.ORTHOTOLIDINE ARESNITE TEST
It is a good practice to test for residual chlorine at
the end of one hour contact . If the free residual
chlorine level is less than 0.5mg/l , then the
chlorination procedure should be repeated before
any water is drawn .During epidemics of cholera
wells , should be disinfected everyday.

16. THE DOUBLE POT METHOD
An improvement devised by the National Environmental Engineering
Research Institute , of Nagpur India . 1.This method uses two
cylindrical pots , one placed inside the other .
2. The inside height and diameter are 30 cm and 25 cm respectively ,
for the outer pot . 3.A hole 1 cm
in diameter is made in each pot , in the inner pot the hole is in the
upper portion, near the rim and in the outer pot it is 4 cm above the
bottom.
4. A moisteneand mixture of 1 kg of bleaching powder and 2 kg of
coarse sand { approx. 2mm in diameter } . The inner pot is filled with
this mixture upto 3 cm below the level of the hole ,inner pot
introduced into the outer pot.
5.Cover the mouth of pot with polyethylene foil. Thedouble pot
method reduce the risk of overchlorination.

17. 7. The double pot is lowered into the well by means
of a rope attached to well kerb. The pot should be
immersed at least 1 m. below the water level to
prevent damage by the buckets used for drawing
water.
8. It has been found that this device works
satisfsctory for 2-3 weeks in small household wells
containing about 4,500 L of water and having a
draw off rate of 360-450 L per /day.

19. PRECAUTIONS SHOULD BE TAKEN WHEN
CHLORINATING WELL.
Electrical safety – 1. turn off the pump circuit breaker before
removing the well cap and while working on the well.
2. Wear rubber sole shoes or boots preferably waterproof .
Chemical safety -1. always follow manufacture use and safety
directions .
2. Avoid eye and skin contact , wear protective goggles or a
face shield and rubber gloves when working with bleach .
3. Do not mix bleach with other chemical as they may form
harmful gases.

20. Respiratory safety -1.underground well pits pose an
extreme hazards , as they frequently contain a build
up of toxic gases or simply lack of enough of
oxygen to sustain life .
2.Leave disinfection of well in pit to professional
licensed well contractor or pump installers.
3. Harmful gases may be generated during
disinfection avoid inhalation of fumes and make
certain enclosed space adequate ventilation before
starting disinfection.

21. CONCLUSION
Chlorination of well is a process in which chlorine
gas is used for disinfection of water well and
making water drinkable , by using different step and
method .

22. ANY DOUBT??
.

23. RECAPITULATION
1. Define chlorine demand ? .
2. what is total chlorine ?
3. Enlist the setp of chlorination of well.
3. What is double pot method ?
4. How can you check efficacy of chlorination ?
5. What kind of precaution measure used during
chlorination of well ?