[Assam] Seems a sensible idea especially for the flood devastated hour of the day.

[Bartta Bistar]

Mukti Pani Filters (Freedom Water Filters) for the Prevention of Water born
Diseases in Flood Affected Region of Bangladesh, India,Nepal and other
nations.

http://www.bangladesh-web.com/view1.php?hidDate=2007-08-15&hidType=SCI&hidRecord=0000000000000000168695



Tuesday August 14 2007 16:23:08 PM BDT


 <matribhumi_bd at yahoo.com>

Meer Husain, USA <matribhumi_bd at yahoo.com>



Mukti Pani Filter #1 can be effectively used to prevent waterborn diseases
such as cholerea, diarrhoea etc in flood affected nations. The Mukti Pani
Filter is simple, cheep and very effective in removing smell and organic
substances from bad water in flood affected areas. After filtration of flood
affected surface water, dug well water and tube well water from above the
arsenic contaminated zone, the filtered water must be treated with chlorine
to kill bacteria. Please take a look at the filtration and chlorination
process as given below:

Mukti Pani Filter #1: is a gravity, mono media water filtration system.
Granular charcoal ranges from 1.0-3.0 mm sizes are packed in a 4 to 5 gallon
perforated plastic bucket. About 5 small holes of 3-4mm size at the bottom
(around center) of the bucket provide water flow of 1-1.5 gallon/minute/ft2.
A steel wire or plastic screen of <1.0 - >0.85 mm mesh size is placed at the
bottom of the bucket (inside) to retain the charcoal grains on the screen.
The charcoal grains are laid on thescreen and the thickness of the charcoal
bed ranges from 5-6 inches. The charcoal or activated carbon is used as
filter media to remove taste and odor causing compounds as well as organic
substances from water. This filter is used when source waters are free of
turbidity and color. These types of filters should be used all over
Bangladesh and West Bengal of India before disinfecting waters with
chlorine. The water flow through the charcoal media should not exceed more
than 1 -2 gpm/ft2. This low flow of water through the charcoal media would
provide enough contact/residence time to water with charcoal for removing
odor, taste and organic matters. Microorganisms will not be removed by this
process and as a result after filtration the water must be treated to kill
pathogenic bacteria.

Turbidity Removal Process: Significant amount of turbidity of low turbid
water can be reduced if the waters are left undisturbed for about 2-3 hours.
The silt and clay size particles are settled at the bottom of the water
container. The water may then be slowly removed from the water container
without agitating the settled turbid substances. This filtration process for
the reduction of turbidity materials from water is the oldest known
technique and people have been using this process for thousands of years.
The people of Bangladesh , India, Nepal and other flood affected nations
around the world may effectively reduce the turbidity of water by this
process and in that case, they can effectively use Mukti Pani Filter #1 for
removing odor, taste and organic compounds from waters.

Disinfection of water:
In developed countries, pathogenic organisms in water that cause various
types of diseases such as cholera, typhoid, dysentery, diarrhea etc. are no
longer a problem due to proper water protection, treatment and monitoring.
Boiling water is expensive but very effective process known for centuries
for killing pathogenic bacteria in water. There are several chemical
disinfectants are being used today for water treatment of which chlorine
disinfection is simple, inexpensive and very effective. Chlorination is the
oldest method of continuous disinfection for public water supplies. There
are two theories regarding chlorine disinfection mechanism. One theory views
that the vigorous action of chlorine against the bacterial cell destroys
bacteria. The other theory is that the organisms die of starvation because
the toxic nature of chlorine inactivates enzymes which empower
microorganisms to use their food supply.
Both Calcium Hypochlorite and Sodium Hypochlorite are being extensively used
for treatment of potable water. The chemical reactions of hypochlorites with
water are as follows:
Calcium Hypochlorite Reaction: Ca(OCl)2 + 2H20------> 2HOCl + Ca(OH)2
Sodium Hypochlorite Reaction: NaOCl + H20 -----------> HOCl + Na(OH)

Chlorine Treatment Dosage:
In USA most health organizations recommend potable water to be treated with
either Calcium Hypochlorite or Sodium Hypochlorite with a concentration
range from 1-4 ppm. In Bangladesh and West Bengal the same dosage can be
effectively used for disinfecting water. The following chlorine dosage chart
for 5% Sodium Hypochlorite (unscented) can be conveniently used for desired
dosage.

Quantity (gal.) 1- PPM 2-PPM 3-PPM 4-PPM 5-PPM
1000 3.0 oz 5.5 oz 8.0 oz 10.5 oz 13 oz
500 2.0 oz 3.25 oz 4.5 oz 5.75 oz 7.0 oz
200 1.0 tbsp 2.25 tbsp 3.5 tbsp 4.75 tbsp 6.0 tbsp
100 2.0 tsp 4.5 tsp 7.0 tsp 9.5 tsp 12 tsp
50 1.0 tsp 2.25 tsp 3.5 tsp 4.75 tsp 6.0 tsp
25 0.5 tsp 1.13 tsp 1.75 tsp 2.40 tsp 3.0 tsp
10 0.25 tsp 0.55 tsp 0.90 tsp 1.20 tsp 1.5 tsp
5 0.25 0.45 tsp 0.65 tsp 0.80 tsp 1.0 tsp

Besides, the above chart, the following formula can also be used to
calculate the amount of clorox/hypochlorites (or other bleach containing
5.25% Sodium Hypochlorite) necessary to produce a given dosage in a known
volume of water: b=VC(2.44 X 10-3 or VC/410.
Where b = ounces of bleach
V = volume of water in gallons
C = desired dosage in ppm
410 is the concentration produced by one ounce of clorox in one gallon of
water.

Example: add 3 ppm to 1200 gallons.
b = 3 X 1200/410 = 8.78 oz.
1 oz = 2 tbsp (tbsp-tablespoon)
1 tbsp = 3 tsp (tsp-teaspoon)

The filtered water should be stored in a clean and tightly covered plastic
container or other corrosion resistant container for proper disinfection of
water. A required amount of hypochlorite for desired concentration can be
calculated from the above chart. (Example: add 4 ppm concentration to 100
gallons, the amount of hypochlorite is 9.5 tsp.). After adding hypochlorite
solution, the treated water needs to be thoroughly mixed. The container
should be properly covered and let stand for 30-60 minutes. After that the
cover should be removed to release the chlorine gas. The treated water is
now safe and ready for consumption. If the disinfected water strongly
smells, the water should be aerated by pouring it from one container to
another to remove smell and taste. The smell and the taste can also be
removed by uncovering the container and letting water stand for 3-4 hours
before consumption.

If granular Calcium Hypochlorite is used , then a stock solution needs to be
prepared by following manufacturer's instruction. The above chart and
formula can be used for the calculation of desired amount of hypochlorites.

Precautions:
Before disinfection, water must be filtered first. Because the reaction of
chlorine with organic matter present in unfiltered water may produce
Trihalomethanes (THMs) which are known carcinogens. Therefore,water must not
be disinfected with chlorine before filtration of water.

Disinfection of Filter media:
The filter media should be washed once a month with 4-5 gallons of water
with at least 100 ppm concentration of clorox bleach. The holes of the
bucket should be plugged or the bucket filter should be placed in a bigger
flat container. The bleach mixed water should be poured into filter media
and let stand the solution for an hour and then drain the bleach water and
rinse the filter media 2-3 times with clean water. This cleaning process
will kill any bacteria developed in filter media.

Disinfection of Flood Affected Tubewells and Dugwells:
Before using water from a flooded dugwell and tube well, it should be
checked, cleaned, and disinfected. This is for health and safety purposes.
Tubewell and dugwell waters could be treated with a chlorine dose of at
least 500 mg/L by following standard Shock chlorination procedures.
Chlorination is the oldest and best method of continuous disinfection for
public water supplies. It is cheep, reliable, easy to use and monitor and it
is safe and environment friendly. The NGO's, local govt. officials ,and
community leaders and activists, educators and other professionals can
easily and properly use the above mentioned filtration and chlorination
method for providing safe water to the flood affected nations.


Respectfully,
Meer Husain, P.G.
Professional Geologist
Kansas Department of Health & Environment.
And Adjunct Faculty
Cowley County Community College.
Team Leader-Cowley County Community College International
Arsenic, Water, Ecosystem & Environment Research Center.
Wichita, Kansas, USA.
E Mail : matribhumi_bd at yahoo.com
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