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ENVIRONMENTAL STUDIESPROJECT
TOPIC :
Introduction :
What is thermal pollution ?
Thermal pollutionis the degradation of water quality by any process that changes ambient water temperature.
Diagrammatic presentation of Thermal Pollution :
Explanation :It occurs when an industry removes water from a source (e.g. , a
river) ,uses the water for cooling purposes , and then returns the heated
water to its source . Power plants heat water to convert it into steam, to
drive the turbinesthat generate electricity . For efficient functioning of the steam
turbines , the steam iscondensed into water after it leaves the turbines . This
condensation is done bytaking water from a water body to absorb the heat . This heated
water , which is at least 15 degreescelsius higher than the normal , is later discharged back into the
water body .
Causes :
Nuclear power plants .
Deforestation
Soil Erosion
Nuclear power plants
->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 .
Deforestation
->The decrease in vegetation increases the amount of light that hits the water, which increases the temperature of the water.->Deforestation also increases erosion .
Soil Erosion
->Erosion makes the water muddy, which increases the light absorbed .
Effects : -> Thermal shock – aquatic life adapted to a certain water temperature can go into shock when the temp is changed even 1 or 2 degrees.
->Oxygen dissolved in water decreases .
->Increases the rate of photosynthesis, which increases the amount of plant growth .
->Increases the metabolic rate of fish, which increases their need for oxygen .
Biotic effects :
-> Changes in the environment may also result in a migration of organisms to another , more
suitable environment , and to in- migration of organisms that normally only live in warmer
waters elsewhere . As a result one has the problem of compromising food chain of the old
and new environments . Biodiversity can also be decreased as a result .
-> Changes of even one to two degrees celsius can cause significant changes in organism
metabolism and other adverse cellular biology effects . Principal adverse changes
can include rendering cell walls less permeable to necessary osmosis ,
coagulation of cell proteins , and alteration of enzyme metabolism . These cellular level effects can adversely affect mortality and
reproduction .
Control measures :
-> Energy chips (Energy Ciptm)->Desalination plants (what problems can this lead to?)->Less nuclear power (what are some alternatives?)->End shoreline deforestation->Prevent soil erosion (what are some methods?)
-> Cooling ponds , man made bodies of water designed for cooling by
evaporation , convection and radiation .-> Cooling towers which transfer waste
heat to the atmosphere through evaporation and/or heat transfer .
-> Cogeneration , a process where waste heat is recycled for domestic and/or
industrial heating purposes .
This 1988 thermal image of the Hudson river highlights
temperature changes caused by discharge of 2.5 billion gallons of water each day from the Indian
Point power plant . The plant sits in the upper right of the photo - hot
water in the discharge canal is visible in yellow and red , spreading and cooling across the entire width
of the river . Two additional outflows from the Lovett coal-fired power plant are also clearly visible against the natural temperature of
the water , in green and blue .
REFERENCES :
-> Google . -> Slide share .
-> Thermal effects . -> Wikipedia .
PRESENTED BY :SAVIJ JAIN
B.COM (HONS) .ROLL NO : 2010
Thank you