Environmental

1. Presented by
S . M. Agilan

2. CONTENT
⯈ Introduction
⯈ Explanation
⯈ Sources
1.Nuclear power plant
2.Coal fired power plant
3.Hydro electric power plant
4.Thermal shock
5.Industrial effluent
6.Domestic sewage
7.Deforestation
8.Soil erosion
⯈ Effects
⯈ Biotic effects
⯈Thermal pollution in streams
by human activities
⯈ Control measures
⯈ Conclusion

3. •Thermal pollution is the degradation of water
quality by any process that changes ambient water
temperature.
•It is the harmful increase in water temperature in
streams, rivers, lakes, or occasionally, coastal ocean
waters.
•A temperature increase as small as 1 or 2 Celsius
degrees (about 2 to 4 Fahrenheit degrees) can kill
native fish, shellfish, and plants and species, often
with undesirable effects.

5. The major sources of thermal pollution are discharge of
heated water or hot waste material into water bodies from
⯈ Nuclear power plant
⯈ Coal fired power plants
⯈ Hydro electric power plant
⯈ Thermal shock
⯈ Industrial effluents
⯈ Domestic sewage
⯈ Deforestation
⯈ Soil erosion

6.  Nuclear power plants use
water as a cooling agent.
After the water is used, it
is put back into a water supply
at 9-20oC warmer .
Emission from nuclear
reactors increase the
temperature of water bodies.

7.  Coal is utilized as a fuel.
Condenser coils are cooled
with water from nearby lake or
river.
effluents
water.
marine
The heated
decrease the DO of
 Damages the
organisms.

8. Generation
electric power
of hydro
sometimes
results in negative thermal
loading in water systems.
Creates less heat on
water sources less than
nuclear power plant.

9.  When a power plant first
opens or shuts down for
repair or other causes, fish
and other organisms
adapted to particular
temperature range can be
killed by the abrupt change
in water temperature
known as "thermal shock."

10. Discharged water from
steam-electric power industry
using turbo generators will
have a higher temperature
ranging from 6 to 9˚C than
the receiving water.
In modern stations,
producing 100 MW, nearly one
million gallons are discharged
in an hour with increase in
temperature of the cooling
water passing by 8 to 10 ˚C .

11. Sewage is commonly
discharged into lakes, canals
or streams.
Municipal sewage normally
has a higher temperature
than the receiving water.
Increase in temperature of
the receiving water decreases
the dissolved oxygen of water.
The foul smelling gases
increased in water resulting in
death of marine organisms.

12.  Streams and small lakes
are naturally kept cool by
trees and other tall plants
that block sunlight. People
often remove this shading
harvest the wood in
vegetation in order to
the
trees, to make room for
crops, or to construct
buildings, roads, and other
structures.

13. Removal of vegetation far
away from a stream or lake
can contribute to thermal
pollution by speeding up
the erosion of soil into the
water, making it muddy,
which increases the light
absorbed .

14.  Reduction in dissolved oxygen: Concentration of
Dissolved Oxygen (DO) decreases with increase in
temperature.
 Interference in reproduction: In fishes, several
migration and reproduction depend on
activities like nest building, spawning, hatching,
optimum
temperature.
directly
 Direct mortality: Thermal pollution is
responsible for mortality of aquatic organisms.
 Increase in toxicity: The rising temperature
increases the toxicity of the poison present in water.

16. Thermal pollution in streams by
human activities
 Industries and power plants use water to cool machinery
and discharge the warm water into a stream.
 Stream temperature rises when trees and tall vegetation
providing shade are cut.
 Soil erosion caused due to construction also leads to
thermal pollution
 Removal of stream side vegetation
 Poor farming Practices also lead to thermal pollution

17.  Desalination plants
 Less nuclear power
 End shoreline deforestation
 Prevent soil erosion

19. Artificial lakes:
These are human – made water bodies Which
gives a potential alternative for colling of power plant
The discharge of warmed effluents at one end
of lake and withdrawing cooling water from another end
of the lake.
The heat of artificial lake is finally dissipated
through the evaporation.
C00LING TOWERS
In this technique, a condenser is used for cooling
of heated effluents at the time of returning to the water
bodies

20. CONCLUSION
 Ensure to use 100% renewable sources
 This pollution negatively affect the yield and
quality of crops
 The plant can be considered at most
important modes to use solar thermal and
biomass power in future….