1. Waste disposal
MOHD. TARIQUE
P.G. SCHOLAR
DEPARTMENT OF TAHAFFUZI WA SAMAJI TIB
NATIONAL INSTITUTE OF UNANI MEDICINE ,KOTTIGEPALYA,
MAGADI MAIN ROAD, BANGALORE- 91

2. Garbage on a city street
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3. Contents
Solid waste disposal
 Human waste disposal
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4. Solid waste disposal
Solid waste includes food waste, paper,
plastics, wood, metal, glass, bricks,
concrete and any discarded material
 Usually human excreta is NOT included in
this
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5. A person walking
through garbage
searching for useful
things
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6. Health hazards of waste
Fly breeding
 Attracts rats
 Soil and water may get contaminated
 Produces bad smell
 Bad to look at
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7. Methods of disposal
Burning/incineration
 Dumping
 Controlled tipping
 Composting
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8. Burning/incineration
All combustible material can be burned
 Materials like glass, metal, concrete will
not burn
 Hospital waste is burned in incinerators
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9. Dumping
A simple method is to dump the waste in
low lying areas
 It will fill the area and the waste will over a
period of time turn to manure (‫)السماد‬
 However open dumping will attract birds,
flies, rats etc.
 Must be done far away from the cities
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10. Controlled tipping
Is a good method
 Pits or trenches are dug and one layer of
waste is deposited and is covered with
earth.
 Then another layer is added till the pit is
filled
 Over a period of time the waste will turn
into manure
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11. Composting
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Is a method of combined disposal of waste and
human feces
A pit or trench(‫ )خندقه‬is dug
A layer of human feces is spread and over it a
layer of waste is spread and then human excreta
and so on till it reaches the surface level
A final layer waste is added and covered with
earth.
After 4-6 months it will be converted to manure
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12. Cross section of compost pit
Soil
Garbage
Human excreta
Garbage
Human excreta
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13. Disposal of human excreta
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Human excreta is infected material containing
many pathogenic organisms
Contamination of soil, water and food can lead
to many diseases
‘Sewage’ is waste water containing human
excreta and industrial wastes
Sewage is taken to treatment plants to make it
safe
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14. Important stages of purification of
sewage are:
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Filtration – to remove large solid waste like
stones, glass, metal pieces etc.
Primary sedimentation
Aeration and oxidation
Secondary sedimentation
Sometimes untreated sewage is directly
discharged into sea
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15. Pictorial representation of a sewage treatment plant
Primary
Sedimentation
Secondary
Sedimentation
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16. Sewage treatment
The effluent is harmless and can be used
for irrigation
 The sludge can be disposed of by
composting or dumping
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17. Excreta disposal in ‘unsewered’
areas – villages, small settlements
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Pit latrines – for temporary camps/emergencies
A
large pit is dug and people defecate into it.
 When it is 2/3rd full it is covered with earth and a new
pit is dug
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Septic tanks – for individual homes, public
latrines
Chemical toilets – used in planes and boats Excreta
is sterilized by the chemical and disposed off
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19. Pictorial representation of septic tank
Aerobic
oxidation
Anaerobic
digestion
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20. Summary
Garbage and human excreta have to be
disposed off properly to prevent health
hazards
 Garbage can be disposed off by –
dumping, controlled tipping and
composting
 Human excreta can be disposed by
sewage treatment on a large scale
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21. Summary
Other safe methods of disposal of human
excreta are – septic tank, pit latrine and
chemical toilets
 It is very important to keep the
environment clean to prevent diseases
and keep the community healthy
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